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- Creator:
- Percolla, Marta I.
- Resource Type:
- Thesis
- Campus Tesim:
- Bakersfield
- Department:
- Biology
- Creator:
- Yanez, Ivette
- Resource Type:
- Thesis
- Identifier:
- 10047
- Campus Tesim:
- Bakersfield
- Department:
- Biology
- Creator:
- Wilder, William H
- Description:
- The Goraori acetylthiocholine technique was used to investigate the distribution of cholinesterase in fourth instar larvae of Culiseta inornate (Nilliston). Fixed and especially prepared larvae were incubated in the substrate solution for the required time, the larvae were imbedded in paraffin, and serial sections were prepared. Microscopic examination of the material revealed a strong histochemical reaction throughout the central nervous system. Faint reactions, not apparent in many of the preparations, were sometimes found associated with muscle, gastric caecae, or Malpighian tubules. The use of selective enzyme inhibitors indicated that the cholinesterase in C. inomata larvae cannot be catagorized as either acetylcholinesterase or pseudo-cholinesterase.
- Resource Type:
- Thesis
- Identifier:
- ocm64178425
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Benjamin, Christina Joyce
- Description:
- Zebrafish is an important model species to study vertebrate development. One particularly interesting aspect of fish ontogeny, which zebrafish larvae exhibit, is the high tail beat frequency up to 10 times higher than that of adult fish. Larvae therefore require a different muscle fiber type than adult fish. This study identifies the changes in muscle protein composition that might underlie this change in muscle contraction frequency. This question is interesting because contraction frequencies above 80 Hz require the so-called superfast muscles, a muscle type so far only been identified in non-locomotory muscles not required to generate significant forces. Superfast muscles are known to differ from normal fast muscles in several proteins, including myosin heavy chain. In this study we will focus on myosin, the largest protein fraction of a muscle that constitutes 40- 50% of total muscle. This study identifies and validates a protocol for myosin protein extraction and identification of myosin isoforms. Fast myosin heavy chains (210 kD) were identified in hatchlings (not yet swimming actively) and in adult Zebrafish (tail beat frequency 10 Hz). In 6-d old larvae (swimming actively, tail beat frequency 100 Hz), we found an isoform (160kD) that was identified in cat masseter muscle, which is a muscle with superfast contraction characteristics. We identified isoforms by probing Western blots with primary antibody (MYH1/2/3) against myosin heavy chains. BCA and ImageJ analysis were performed to quantify the amount of total protein and the myosin content.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Houk, James L
- Description:
- Gregarines are parasitic protozoa belonging to the sporozoan subclass Telosporidia. They occur most often in invertebrate groups with a metameric level of development. Some, however, have been described from mollusks which do not have a metameric level of development (Cheng, 1967; Leger and Duboscq, 1908). The eugregarines of arthropods, including barnacles, are typically members of the suborder Cephalina. Cephaline gregarines are described as polycystid organisms to contrast them with the unsegmented monocystid gregarines. The bodies of cephaline gregarines are divided into two segments, an anterior protomerite separated from the posterior deutomerite by a membrane which does not restrict movement of the endo-plasm but does set off the nucleus in the deutomerite. A holdfast, the epimerite, is located on the anterior end of the young sporont. The gregarine remains temporarily attached externally to the cell in which it developed. It subsequently loses the epimerite and becomes a trophozoite which moves about freely, usually in the gut lumen.
- Resource Type:
- Thesis
- Identifier:
- ocm60129979
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Healer, Rain
- Description:
- The Endangered Species Recovery Program (ESRP) is supervising land restoration in southwest Fresno County through the federally funded Land Retirement Project. The reclaimed land is adjacent to currently farmed land, and there is grower concern that native vegetation on the reclaimed land will function as a reservoir for insect pest infestation. The purpose of my research was to conduct an initial inventory of Diptera present on some of the California native plants that are utilized in habitat restoration by the ESRP in southwest Fresno County. Dipteran populations were sampled on three of the species of native plants grown within the ESRP�s native plant seed nursery and on the same three plant species that also occur within non-nursery sites in the general area surrounding Tranquillity. This research provided preliminary information on dipteran trophic guilds and the potential amount of ecological redundancy present within this ecosystem. It also provided baseline biodiversity data for future research. Future work will estimate species richness, abundance, and pest/beneficial significance from this baseline data. No significant difference was found between collection sites in taxa collected, trophic guild, number of Diptera collected, and pest status.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Slonka, Stephanie Marie
- Description:
- As California continues to persist in a state of severe drought, residents of the Fresno Clovis Metropolitan Area (FCMA) are slowly making changes to reduce their water usage and to be conscious of how this resource is utilized in their landscape. Since the advent of water metering in 2013 and the Governor’s declaration of California’s state of emergency, it is unknown how the response of our wildlife populations will fare, in particular, avian populations. Several studies have indicated that a long-term drought and the reduction of water availability can have adverse effects on the avian communities within a city. A pre-metering (2008) to post-metering (2015) comparison was conducted using multivariate analyses to determine how the landscape changed over time and if avian communities have responded to the “effective drought” that the FCMA is experiencing. Since pre-metering, bird abundance and the species richness of the FCMA has decreased and new habitat variables are now shown to predict bird species richness and abundance. Other essential aspects of the urban landscape that have been shown to make an impact on the bird communities had a negative response to certain socio-economic variables and there being no effect on foraging guilds in relation to certain irrigation intensities as reported in pre-metering years.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Holland, V. L
- Description:
- The purpose of the present study is to gain some insight into the complex of factors that create the canopy effect with emphasis on the microenvironment that is associated with the vegetative differences. Data recorded weekly included the measurement of plant growth, precipitation, air temperature, soil moisture, and soil temperature. Other studies involved pH, bulk density, permanent wilting percentage, moisture equivalent, field capacity, organic content of the soil and. plant distribution. The determination of all factors involved was not possible in the two growing seasons studied, but accrued data suggests certain ecological relationships. The investigation was undertaken at the San Joaquin Experimental Range (SJER) near O'Neals, California, 25 miles north of Fresno. The SJER is situated on the east side of the San Joaquin Valley in the Sierra Nevada foothills. The natural vegetation is typical of the foothill woodland community (as recognized by Munz, 19&3) consisting of trees 15-70 feet tall in an open woodland with scattered brush and grassland between the trees.
- Resource Type:
- Thesis
- Identifier:
- ocm58723865
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Sarvabhowman, Preethi
- Description:
- In the present study, we studied the growth characteristics of two species of green algae; Dunliella primolecta and Botryococcus braunii, in fruit industry wastewater and also studied the COD removal from wastewater by these species. We found that both the species of algae could grow better in 25% (v/v) wastewater reaching the stationary phase when compared to other concentrations of wastewater. However, Dunaliella primolecta was found to be growing faster than Botryococcus braunii, reaching a concentration of 8x106 cells/mL in 15 days. Also, it was found to remove 63% of COD from fruit industry wastewater obtained from Wawona Frozen Foods, CA. We also reported the first successful Agrobacterium tumefaciens method of transformation for the green algae Dunaliella primolecta using the binary vector pCAMBIA 1301 containing the genes coding for GUS (B-Glucuronidase) and hpt (hygromycin phospho- transferase). The developed transformation protocol would pave a way for easy manipulation of Dunaliella primolecta for the production of biofuels and other secondary metabolites.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Upton, Kelli Renee
- Description:
- The general stress response principally results in the release of cortisol, with the overall effect of mobilizing metabolic energy and redirecting it towards homeostatic maintenance. Consequently, an important factor altered by stress is food intake. In several teleost species, a decrease in food intake following stress has been observed, though the neuroendocrine mechanism controlling the reduction in food intake during stress has yet to be determined. These studies were designed to investigate the effect of an acute stress on food intake and brain expression of corticotropin-releasing hormone (CRH), neuropeptide Y (NPY), ghrelin and ghrelin�s receptor and whether these effects are mediated by cortisol. Therefore, metyrapone, a cortisol synthesis inhibitor, was administered via feed in three doses of 10, 25, and 50 mg/kg body weight for 1 wk prior to a 30 min crowding and handling stress. Following the stressor, fish were allowed to feed for 1 h. Stress reduced food intake, while elevating mRNA levels of CRH, an appetite suppressor. Additionally, metyrapone treatment dose-dependently blocked the stress-induced reduction in food intake. While NPY and ghrelin levels were unchanged, an increase in ghrelin receptor activity suggests a function for ghrelin in regulating overall metabolism in response to stress. The elevation of CRH mRNA levels was also reversed with metyrapone treatment, suggesting cortisol and CRH play a role in mediating reduction of food intake during stress in tilapia.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Anderson, Kathleen Mary Kennedy
- Description:
- In this study, substrate and water agitation of the echinoid habitat are related to the entocommensal incidence. Host species examined at Eniwetok had higher densities of entocommensal ciliates in lagoon waters than in surf waters on the fringing reef (Berger, 1964b). Lower infaunation rates for irregular hosts have been related to the ingestion of substrate unsuitable as food for ciliates (Berger, 1963b). Echinoid distribution and habitat data for areas having taxonomically similar echinoids to those of American Samoa have been reported for the Indo—Pacific islands of Hawaii (Ebert, 1971) and the West Indies-Florida area of Key Largo, Florida (Kier and Grant, 1965).
- Resource Type:
- Thesis
- Identifier:
- ocm56986158
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Janzen, Whitney Jean
- Description:
- In response to a stressor, an animal�s physiology is altered in an attempt to maintain homeostasis. Cortisol, a corticosteroid hormone that binds to the glucocorticoid receptor (GR), has widespread actions which mediate the stress response. In an aquaculture setting, fish are exposed to many stressors, which may negatively impact their growth and metabolism. The objectives of my thesis were to investigate the effect of cortisol on food intake, the hormonal regulators of appetite, glucose metabolism, and the growth axis. The tilapia (Oreochromis mossambicus) was used as the model because of its rapid growth and worldwide popularity as an aquaculture species. It was found that cortisol reduced food intake, which appears to be mediated by a reduction in the mRNA levels of the orexigenic hormones (NPY and ghrelin) in the telencephalon and diencephalon regions of the brain, as well as suppressed plasma and stomach ghrelin levels. mRNA levels for genes related to growth (IGF-I, GHR1, and GHR2) were elevated in the liver and muscle in response to cortisol. Total glucose levels were also elevated, as well as INSR mRNA in the liver. Treatment with the GR antagonist (RU-486) generally reversed the effects of cortisol, except in certain tissues, which may indicate the presence of multiple GR isoforms in tilapia. These results provide a mechanism for cortisol�s anorexigenic effects in tilapia.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Fok, Katherine Sik-Ling
- Description:
- An earlier study on the effect of excess DL-methronine on Saccharomyces cerevisiae strain 3701B when cultured on a rich medium showed that there was an inhibition of cultural development during the first 6 to 12 hours. However, a sudden and sharp increase in cultural development occurred after the inhibition period. The purpose of the present study is to observe the effect on S_. cerevisiae when grown on defined and minimal media in the presence of varying concentrations of DL-methionine. The ∝-hydroxylmethyl group of serine is the dominant donor of methyl group in methionine synthesis, and the enzyme catalyzing the transfer of the ∝-hydroxylmethyl group in the formation of methionine is serine hydroxy-methylase. It is our present interest to note the effect of varying concentrations of DL-methionine on the production and activity of serine hydroxymethylase. It is also of Interest to note if varying concentrations of methionine would have any effect on the production of glutamic-oxalacetic aminotransferase, an enzyme which is not directly involved in methionine biosynthetic pathway.
- Resource Type:
- Thesis
- Identifier:
- ocm58533112
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Castro, Jamie
- Description:
- Early sexual maturation (precocity) of male salmonids is a serious issue in the modern conservation hatchery. Previous studies have demonstrated a ‘decision window’ of time for sexual maturation for Spring-run Chinook salmon beginning in the fall, during which the fish use biological and environmental cues to “decide” whether to mature for the following season. The months signifying the beginning and end of this fall decision window for California strains remains unclear. Therefore, an experiment was designed to elucidate the beginning and end of the decision window for California strains of male Spring-run Chinook salmon. A total of 628 juvenile males were randomly distributed among six tanks and fed a reduced ration diet during the predicted maturation decision window by adjusting duration and timing of diet reduction for each group. An additional 53 males were fed a high ration diet throughout the decision window. Individual weights and lengths were measured monthly. Precocity ranged from 32% to 10%, with the highest rate observed in the group fed a reduced ration between July- January and the lowest rate observed in the group fed a reduced ration between August-February. Additionally, condition factor (an estimation of adiposity), was observed to increase for males who would mature during the spawning season subsequent to the study period. Thus, it may be possible for hatcheries to implement feed reduction strategies to manage adiposity and precocity in broodstock.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Whalen, William, Alexander
- Description:
- Traditional cell culture techniques grow cells in a two-dimensional (2D) format on compatible surfaces, but cells do not grow like this in vivo. A fast-emerging alternative is three-dimensional (3D) cell culture, which encourages cells to work together while suspended in a matrix rather than relying on adhesion to a treated surface. Most studies utilize a commercially available, industry standard recombinant basement membrane substitute--Matrigel ; however, this is proprietary and expensive. For these studies, my goal was to refine an alternative to Matrigel for use as a suspension media and surrogate extra-cellular matrix (ECM). My efforts focused on economical methylcellulose (a synthetic derivative of cellulose dissolved into basal growth media and called Methocel) in combination with rat-tail collagen (Type I). Optimized concentrations were evaluated towards the formation of spheroids among several cell lines including all three isogenic variants of a metastatic breast cancer cell line, MDA-MB-231, notoriously difficult to adapt to spheroid culture. I chose to use the metastatic breast cancer cell line MDA-MB-231 and two isogenic variants, MDA-MB-231Bo and MDA-MB-231Br, shown to regularly metastasize to either bone or brain respectively. This cell line series was used to evaluate the potential of this low-cost matrix to facilitate spheroid cultures; to determine expression changes in the canonical cell adhesion components Integrins (2, β1, and β4), as well as, E-Cadherins (ECAD) and N-Cadherins (NCAD); and to evaluate the functional significance of the spheroids to a relevant drug treatment. Here, by image analysis of spheroid metastatic progression and semi-quantitative RT-PCR analysis of metastatic cancer cells, we show the potential of this system in observing cancer cell migration and cellular behavior under more in vivo-like conditions, bridging the gap between basic two-dimensional cell culture and the animal model. Furthermore, through the use of this powerful model, we showed the efficacy of zoledronic acid to inhibit osteotropic breast cancer cell migration by up to ~14% post-72h treatment time. Lastly, zoledronic acid treated spheroids showed a continued improvement towards regaining more epithelial-like gene transcription profiles in genes associated with cells having undergone epithelial-mesenchyme transition. Together, these data add validity to our claim that metastatic studies using a surrogate extracellular matrix, such the one suggested in this study, continue to bridge the gap between typical two-dimensional cell culture and the animal model.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Khorshidchehr, Darius Mehrnoosh
- Description:
- Fish execute a C start when they escape from a predator. Previous studies suggest that fish randomize their horizontal escape trajectories, but bias the response away from the stimulus. The fewstudies that looked at the vertical trajectory found that fish larvae respond to a horizontal stimulus with a downward escape trajectory. This study quantifies the escape trajectories of fish larvae in three dimensions. We use a vertical and a horizontal suction stimulus to explore the effect of stimulus direction on the escape trajectory. We found that zebrafish larvae (age 3 to 12 days post-fertilization) consistently responded to a horizontal stimulus with a downward trajectory. For the horizontal stimulus, out of 70 video recordings, 54 showed escape responses (77.1%). Fifty twoof those responses showed a downwards trajectory (96.3%). Thesedata suggestthat the same trend holds true when we use a vertical stimulus, simulating a benthic predator. The vertical stimulus, out of 131 video recordings, 131 showed escape responses (100%). From those responses, 129 showeda downwards trajectory (98.8%). Given the age range of the larvae, the downward trajectory cannot be explained by asymmetry of the body due to the presence of a yolk sac; the yolksac is absorbed usually at age 5 to 6 days. So the downward trajectory might be a hardwired response (zebrafish larvae are demersal) or indicate that fish have less control over their pitch than their yaw angle �the body movements during an escape response might be able to generate a wide range of yawing moments, but not pitching moments, leading to the observed bias in the trajectories.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Arteaga, Erik Santigo
- Description:
- Klebsiella pneumoniae is a problematic gram-negative bacterium which commonly causes nosocomial infections such as pneumonia, urinary tract infections, burn wound infections, and bacteremia. K. pneumoniae is particularly virulent due to its ability to form biofilms within its host. Recent studies have revealed an upward trend of nosocomial infections caused by multidrug resistant (MDR) strains of K. pneumoniae. Most worrisome are extensively drug resistant strains (XDR), as they can withstand treatment with carbapenems, which are considered the most effective antibiotics in treating microbial infections caused by gram-negative organisms. RNA-sequencing of a biofilm of an MDR strain of K. pneumoniae (BAMC) treated with carbapenems for two hours demonstrated significant differential gene expression in treated biofilms compared to untreated controls. One gene of interest was the alternative sigma factor rpoS which controls the cells’ entry into stationary phase. In this study we attempted to identify the role of RpoS in antibiotic tolerance, virulence, and heat tolerance in K. pneumoniae. A rpoS knockout mutant was generated in the BAMC background. We found that the mutant was not defective in antibiotic or heat tolerance. We believe these responses may be modulated through another mechanism. Our rpoS knockout strain was found to be deficient in virulence in our infection model, Galleria mellonella. This research may provide potential drug targets for MDR or XDRorganisms.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hill, Alya Juwariah
- Description:
- This was the first survey in the central and southern San Joaquin Valley to identify the hard tick species present in this region. Hard tick distribution and diversity were evaluated in Fresno County and adjacent areas by (i) collection of ticks at three different elevation habitat sites and from veterinary sources, and (ii) subsequent phylogenetic comparison using fragments of 16S rDNA. A total of 178 ticks of 4 species were identified: Dermacentor occidentalis (n = 65), D. variabilis (n = 31), Ixodes pacificus (n = 2), and Rhipicephalus sanguineus (n = 80). Each species was restricted to a single habitat, but with detectable genetic variability within each species. R. sanguineus were only collected from dogs, I. pacificus were only collected from Kreyenhagen Peak, D. occidentalis were only collected from Coalinga Mineral Springs, and D. variabilis were only collected from China Creek Park. Further research is suggested to increase numbers of sampled sites, and to evaluate presence of tick borne pathogens.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hwang, Daeun
- Description:
- Parkinson’s disease (PD) is the most common neurodegenerative movement disorder. Research has identified several factors that play an important role in PD, and one of the factors is protein called α-synuclein.Overexpression of A30P or A53T promotes the formation of toxic filamentous inclusions in neurons that mediate motor output, resulting in movement deficits. The present study involved using Drosophila melanogasterto examine the behavioral dysfunction associated with α-synuclein linked to PD. The specific aim of this study was to develop an obstacle avoidance behavioral assay to quantify motor control and movement planning deficits in flies. Flies were genetically altered to carry A30P or A53T protein in specific brain regions known to be associated with sensory integration and locomotor abilities in insectsand their behavior assessed at different ages. Our data suggest that Drosophila expressing α-synuclein exhibit significantly different locomotor responses in speed and distance of negotiating an obstacle, with the greatest deficitsin central complex mutants.Moreover, aged mutant flies had lower success rate in negotiating the obstacle than young flies. These findings suggest that flies expressing α-synuclein may have issues with coordinating and executing fine control of movement in the obstacle avoidance activity. Therefore, this study can provide new insight into our understanding of the potential effects of α-synuclein in PD.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Meyer, Erik
- Description:
- This study investigated the potential effects of cholinesterase (ChE) inhibiting pesticides and thyroid hormone changes from blood mercury (Hg) concentrations in western pond turtles (Emys marmorata) occupying streams in two regions of California, USA. The southern region is suspected of having increased exposure to atmospheric deposition of pesticides originating from Central Valley agriculture compared to the northern region. Total ChE activity of turtles was significantly depressed by 31% (p = 0.005) in the southern region after accounting for additional sources of variation in ChE activity. Male turtles had significantly increased ChE activity compared to females (p = 0.054), but cloaca temperature, length, mass, handling time, body condition, and lymph presence were not significant predictors of turtle ChE activity. Conversely, turtles in the northern region were suspected of having increased Hg exposure from historic gold mines compared to the southern region. Erythrocyte Total Hg (THg) concentrations in turtles ranged from 0.179 to 3.197 mg kg-1, with the highest mean concentrations found in the northern region and the lowest in the southern region. A positive correlation between mean turtle erythrocyte THg concentrations and the number of historic gold mines within a study watershed may exist (p = 0.057). Plasma triiodothyronine and thyroxine (T4) concentrations were not significantly influenced by THg concentrations, although T4 was significantly related to capture time of day (p = 0.042) and body mass (p = 0.031), and males had increased plasma T4 compared to females (p = 0.001).
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Brown, Matthew David
- Description:
- Suction feeding is an important feeding mode in aquatic organisms and is used across a considerable size range, from tadpoles to whales. Our current understanding is based on how adult fish feed and suggests that suction feeding is not effective for organisms just a few millimeters in size. All suction feeders have to overcome the inertial and viscous forces exerted by the water when sucking in water plus prey, yet only the inertial forces contribute to prey capture, while viscous forces contribute just to the cost and reduce the effectiveness of prey capture. Large predators do not need to complete their suction strikes as quickly as small predators because the contribution of viscous forces is low. We therefore predicted that (1) small suction feeders complete feeding events more quickly than large suction feeders, and that (2) smaller suction feeders approach the lower size limit and hence cannot generate the same high flow speeds as larger suction feeders. We focused on two species of the aquatic carnivorous plant bladderwort, Utriculariagibba and U. vulgaris, that capture zooplankton in traps that are just 1-5 mm long. We quantified the movements of the bladders during feeding strikes and their peak flow speeds. We found that bladderwort feeding strikes are much briefer than those of adult fish, and that the smaller bladderwort species, U. gibba, generates slower flows than the larger U. vulgaris, suggesting that U. gibba feed near the lower size limit.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Olson, Eugene A
- Description:
- This study deals with the vertical conation in forage "behavior of the "bird population In a pure coniferous forest association. In addition, it is an attempt to investigate the concept that groups of organisms function in a protoplasmic manner and that life on this earth is a system of conscious or unconscious cooperation, with each organism being an apex of a functional hierarchy and also a foundation stone of many others; each organism is dependent on some other organisms but is also independent of a multitude of others. Food chains and webs are the sustaining factors for the ever-present but fluctuating pyramid of numbers. This study near Nordern, California, beginning July fourth and ending August first, 1951, shows that birds In a forest association will forage in a stratified system in aooordar.se with the height of vegetation levels and where their favorite or most abundant food is located. This paper will Include stratal foraging behavior, an index census of numbers of individuals per species and an annotated checklist of the birds encountered during the study.
- Resource Type:
- Thesis
- Identifier:
- ocm61409632
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Rosenthal, Elianna
- Description:
- The San Joaquin River (SJR) in California’s Central Valley represents the historical southern-most range of Chinook salmon (Oncorhynchus tshawytscha). In 2006, the San Joaquin River Restoration Program (SJRRP) was created to mitigate the negative effects of the Friant Dam which has caused degradation of extended portions of the SJR. The artificially changing hydrology of the SJR affects the thermal dynamics of restoration reaches which plays a significant role in growth and metabolism of juvenile Chinook salmon (JCS). Mass standardized growth rates () of SJR JCS cohorts (n=4) were compared to other wild (n=4) and hatchery (n=10) JCS populations. The estimated of wild SJR are high compared to other wild populations and are comparable to hatchery populations, despite living in what is regarded as “poor conditions.” The temperature optima and critical level for the SJR set by the SJRRP are based on EPA Region 10 (Pacific Northwest). Using a new JCS bioenergetics model with updated parameters and accurate recorded temperatures, bioenergetic model simulations were run to examine population-specific temperature regulation of manifested and potential growth. The results suggest that SJR JCS can continue their high growth rates with ample prey. My results suggest the importance of population-specific growth rate parameters and call into question the practice of applying bioenergetic and metabolic estimates from one population to other populations of Chinook. These data can help inform both water management and salmon conservation, especially in California where river water temperatures are highly regulated by water agencies and conflicting water demands and uses.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Krishnamurthy, Sanjana
- Description:
- This study investigated the impact of different instructional strategies on students’ understanding about the cell cycle in a general education biology course. Although several studies have documented gains in students’ cell cycle understanding after instruction, these studies generally use only one instructional method, often without a comparison group. The goal of this study was to learn more about students’ misconceptions about the cell cycle and how those ideas change after three different evidence-based learning experiences in undergraduate general education. Undergraduate students in six laboratory sections (n = 24; N = 144) in a large public institution in the western United States were surveyed pre- and post-instruction using a 14-item valid and reliable survey of cell cycle knowledge. Cronbach’s alpha for the standard scoring convention was 0.264 and for the alternate scoring convention was 0.360, documenting serious problems with inconsistent validity and reliability of the survey. Operating as though the findings are at least a proxy for actual cell cycle knowledge, score comparisons by groups of interest were explored, including pre- and post-instruction differences among demographic groups of interest and three instructional settings: a bead modeling activity, a role-playing game, and 5E instructional strategy. No significant differences were found across groups of interest or by strategy, but some significant item-level differences were found. Implications and discussion of these shifts is noted in lieu of the literature.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Nichols, Robert D.
- Description:
- The objective of this study was to determine the distribution and interrelationships of the fishes of the San Joaquin River drainage of the Sierra Nevada foothills, which have not been adequately checked since 1898 and 1899 (Rutter, 1908). A complete distributional list of Central California fresh water species was compiled some forty years ago (Evermann, 1931) with subsequent distributional studies limited to one or a few species. Two major f a c t or have warranted this distributional study. (1) extensive development of the area since the turn of the century, which includes intensive agriculture, mining, industry, large population centers; and (2) widespread introduction of numerous species from the eastern United States, which have had considerable effects on the distribution of native fish fauna. These man oriented factors have drastically changed the distribution and quality of fresh water habitats. At this time four rather distinct associations of native and exotic species exist in the foothill streams of this drainage (Moyle and Nichols, in press). The distribution of these associations and the distributions of the individual species are charted.
- Resource Type:
- Thesis
- Identifier:
- ocm61387402
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Thompson, Bruce E.
- Description:
- The oceans, once believed infinitely vast and stable, have recently been subjected to considerable alteration from other than natural sources. The time has come when we must try to control these alterations and attempt to maintain the oceans as a natural system. To accomplish this we must know precisely how this intricate system operates, both physically and biologically. The energy transformations of the photosynthetic plankton lie at the beginning of this system. Logically then, priority should be given to investigations directed towards a better understanding of these basic processes. We must know the physical and biological factors involved, which factors limit the system, the composition and distribution of the plankton, and biology of these constituents. By knowing these factors we can understand the beginning of the marine ecosystem.
- Resource Type:
- Thesis
- Identifier:
- ocm62894063
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Esani, Saika
- Description:
- Persister cells are a small percentage of the bacterial population (0.01-10%) that survive antibiotic therapy along with other stressors. They do this without undergoing any genetic change, only phenotypic variation. The exact mechanisms of persister cell formation are still not completely understood. We are in the process of identifying genes important for persister cell formation in a highly virulent respiratory pathogen, Pseudomonas aeruginosa. This organism is a major health concern, especially since antibiotic resistance is on the rise. We found high levels of differentially gene expression in persister cells through RNA sequencing. Interestingly, we found more genes were actually upregulated compared to downregulated. These results indicate that previously held ideas about persister cell dormancy are debatable. We quantified persister cell formation in selected mutants by directly evaluating the number of colony forming units (CFUs). Selected hits included pyocin synthesis genes, where mutants failed to form any persister cells. We characterized the role of two genes, PA3819 and gshA, through assays of physiological and biochemical functions including pyocyanin production, biofilm formation, and motility of both mutants in order to characterize the role of these genes within the cell. The knowledge derived from these studies will help identify better targets for treatment of P. aeruginosa acute infections, chronic infections, and post-treatment relapses.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hidalgo, Fatima
- Description:
- Suction feeding is a common feeding mode in macroscopic aquatic organisms and the dominant feeding mode in fish. In contrast, microscopic aquatic organisms do not use suction feeding. In fact, the smallest known suction feeders are fish larvae and bladderwort, a genus of carnivorous plants that catches zooplankton in underwater traps, both of which have gapes around 200 microns in diameter. Experimental and theoretical studies of suction feeding have shown that the ability to generate a steep spatial pressure gradient correlates strongly with capture success. Those studies also show that suction feeding is essentially an inertial process and therefore will be effective only if viscous fluid forces can be neglected, which is as long as the gape is large enough and the suction flow (i.e. the negative pressure gradient near the mouth) fast enough to minimize the relative effects of friction. Our current understanding of the hydrodynamics of suction feeding suggests that suction feeding is not effective in small organisms. In fact, both mathematical models of suction feeding, and experimental observations of larval fish suggest that their gape of 200 microns is near the lower size limit of suction feeding and that their suction flows generated by a 0.2 kPa pressure differential are too weak to ensure prey capture. In this project, we explored the lower size limit of suction feeding by characterizing the suction flows of bladderwort and salamanders and using the data collected to develop a robotic model of a suction feeder.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Tanadjaja, Elsie Dekawati
- Description:
- Rhodoliths are free-living coralline algae that produce carbonate sediments in shallow water marine systems worldwide. Rhodalgal sediments, which result from rhodolith breakage and chemical weathering, mix together with living rhodoliths and form shallow water habitats known as rhodolith beds, support a diverse assemblage of organisms. Rhodoliths and sediment cores collected from the El Requeso?n rhodolith bed in Bahi?a Concepcio?n, Me?xico were used to study the basic mechanical and chemical processes involved in rhodalgal sediment production and basic framework of a rhodolith bed. Results showed four major groups of rhodalgal sediments produced from rhodolith breakdown: "cores," "branches," "crumbs," and �dust� that ranges in size from pebbles, sands, to silts. Dissolution of rhodoliths was evident at seawater below pH 7.5 and at 30% dissolution, core breakdown was accelerated and smaller branches were produced. The general vertical trend of coarse-fine-coarse sedimentary texture indicates the temporal dynamics of a rhodolith bed, suggesting movement in south-north-south direction or expansion-shrinkage-expansion of the active part of the bed from past to present. The effect of 30% dissolution seen in the experiment suggests that dissolution occurring in future high CO2 ocean conditions would cause structural changes to shift towards more compacted framework with smaller interstitial spaces, hence changing the habitat quality of the bed.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Shipman, Charles
- Description:
- It is the purpose of this paper to present and analyze the results obtained in neutralization studies of four bacteriophages of Bacillus pumilus. Suppositions as to the interrelations among the four bacterial viruses are presented.
- Resource Type:
- Thesis
- Identifier:
- ocm62263218
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Braganza, Conrad Fredrick
- Description:
- Retired farmland in the western San Joaquin Valley (SJV) of California is frequently colonized by invasive plants that may limit the establishment of native flora. Limited ecophysiological data on native and invasive SJV plant species constrains science-based restoration of native flora. This greenhouse evaluation involved a comparison of photosynthetic rates, in vivo nitrate reductase activity (NRA), and biomass accumulation of two invasive annuals and three native annual species. At 35d and 75d, 15 individuals were harvested to determine total biomass. Photosynthesis was measured using a Li-Cor Li-6400 and in vivo NRA was measured in roots and leaves. At harvest 1, the photosynthetic rate of invasives (15.5�0.56 _moles CO2�m-2 �s-1) was greater (p<0.05) than natives (10.6�0.43 _moles CO2�m-2 �s-1). Natives significantly exceeded (p<0.05) the water use efficiency of invasives by 22% and 31% at harvest 1 and 2, respectively. In all species, leaf NRA exceeded root NRA (p<0.001; p<0.05). The total biomass of invasives significantly exceeded (p<0.05) that of natives at harvest 1 and 2 (0.25�0.003 g and 0.46�0.002 g, respectively). By harvest 2, the relative growth rate (RGR) of natives (0.069�0.03 g�g-1�d-1) exceeded invasives (0.043�0.07 g�g- 1�d-1, p<0.05). Greater early season photosynthesis, biomass and RGR of invasives likely aid in out competing natives and may contribute to low rates of native species establishment on retired farmland.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Ogden, Gary L
- Description:
- The purpose of this paper is to describe some of the factors which influence seed germination and seedling survival or the California Buckeye and to relate these factors to the distribution pattern. Benseler (1969) found that-most seed and seedling mortality was caused by desiccation and fungus damage. Evidence from the present study indicates that other factors may be at least as important to both seedling survival and tree distribution.
- Resource Type:
- Thesis
- Identifier:
- ocm61411177
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Lindegren, James E
- Description:
- Howardula okumural la the only currently recognized sphaerulariid from nitidulid beetles. Its host range Is United to Carpophilus mutilatus. Locality records for this nematode include Alabama, Mississippi, Georgia, Texas, Florida and Mexico, g. okumural females say be found in the haemocoel of all larval instars of the host. The fannies enlarge in the host pupae and expel larvae in the newly emerged adults. Resultant fully developed third stage nematodes penetrate the midgut of deed nod dying adult beetles. They then become quiescent end grouped in the rectum or exit through the anus end locate as dauer larvae under the elytra of the host. They then molt twice end mature within 24 hours, mate mad remain viable up to 16 days in a 0.65 percent Ringer’s saline solution. Compared to control populations thlrty-day old parasitized beetle adults produced one fifth the number of larvae, end the females contained one fifteenth the number of mature ova.
- Resource Type:
- Thesis
- Identifier:
- ocm60756049
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Feaver, Paul E
- Description:
- Amphibians "that: breed in temporary bodies of water are confronted with problems of pool availability and larval mortality due to dessication of the breeding pools. Due to the low normal rainfall during the spring of the year, the mortality to the larvae is great because many pools dry before the larvae are able to complete development. In the area studied there are three species of amphibians which use vernal, pools and other temporary bodies of water for breeding. These are the California Tigar Salamander, Ambystoma tigrinum californiense Gray, the Pacific Tree Frog, Hyla regilla Baird and Girard, and the Western Spadefoot Toad, Scaphiopus hammondi hammondi Baird. The California Tiger Salamander (Ambystoma) and the Western Spadefoot Toad (Scaphiopus) breed only in temporary bodies of water, usually vernal pools. The Pacific Tree Frog (Hyla) breeds both in vernal pools and in permanent bodies of water. The purpose of this study was to try to determine the factors influencing breeding pool selection by Amby stoma, Hyla and Scaphiopus and to observe the development and survival of their larvae in pools selected for breeding. The factors examined in this study were pool size, pool location, the amount of vegetation and zooplankton in the pools, and the effect of mixed larval populations in the pools. The particular area of study was selected because of the number and variety of vernal pools and because all three species of amphibians breed in the pools in the area. The study was carried out from March 14 to May 7, 1.970, although information on the migration and breeding of the amphibians was noted before the initiation of the study.
- Resource Type:
- Thesis
- Identifier:
- ocm58533298
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Marquez, Ernest D
- Description:
- An increased interest has been shown in the exotoxins of the bacterium Staphylococcus aureus and their relationship to disease since 1872 when Klebs, speaking of staphylococcal infections, suggested that these organisms produce disease by means of diffusible substances which he termed "sepsins." Early investigators were able to demonstrate that in addition to dermonecrotic and lethal effects, the staphylococcal toxin had a leucocidic effect on rabbit white blood cells and lysed rabbit erythrocytes. Although this knowledge was available, it was largely neglected until the Bundaberg disaster in 1928. In Bundaberg, Australia, 12 children died after being inoculated with a diphtheria toxin-antitoxin mixture which had become contaminated with S. aureus. The lethal effect was attributed to the staphylococcal toxin. Burnet's (10,11) subsequent investigations of the disaster disclosed that the toxin could be produced in significant quantities for laboratory investigations and that the toxin was a true exotoxin capable of killing rabbits on intravenous injection. These findings prompted increased interest in the investigation of staphylococcal toxins (12, 15, 30, 50). It is now known that a crude staphylococcal toxin preparation is composed of various substances. These include coagulase, staphylokinase, and hyaluronidase, the so-called "spreading factors", Panton--Valentine leucocidin, a distinct enterotoxin, and four hemolysins (17, 63). The latter have been termed alpha, beta, gamma, and delta hemolysins (25, 57, 64, 72). Of these, the alpha hemolysin has received the most attention and has been so frequently associated with the lethal and necrotizing factors that the terms alpha hemolysin and alpha toxin have been used interchangeably. Supernatants from staphylococcal cultures are hemolytic in vitro, lethal for small laboratory animals, produce necrotizing lesions following injection into the skin of animals, cause smooth muscle to undergo contractions and loss of function, and bring about cortical necrosis of the kidneys when injected intravenously into experimental animals (1, 17, 30, 65, 67, 68). Until recently, it had been difficult to ascribe a specific function to alpha toxin because of the unavailability of purified material. However, as more gentle and effective methods of protein separation have become available, attempts at alpha toxin purification and characterization have met with various degrees of success. Several groups of investigators claim to have prepared purified alpha toxin which was homogeneous, producing a single precipitin line on gel diffusion and immunoelectrophoresis (9, 14, 26, 31, 37, 39). With these preparations and with many others known to be impure, a variety of tests have been conducted to determine the activity of alpha toxin. Based on the conclusions reached by various investigators (9, 26, 31, 36) there seems to be some agreement that the lethal, dermonecrotic and hemolytic effect of supernatants from staphylococcal cultures are due to one and the same substance, the alpha toxin fraction (5). Other effects attributed to alpha toxin are a lytic effect on rabbit and human leukocytes (8, 26, 30), necrosis of human skin (26), damage to human platelets (7, 40, 59), damage to rabbit kidney, Ehrlich ascites, human epidermoid (KB), and monkey kidney cells in tissue culture (3, 4, 33), damage to pleuropneumonia-like PPLO) organisms (6), and damage to rabbit liver lysoscmes (8). In this investigation, sane localization of a lethal dose of alpha toxin in the heart and lungs of a mouse after intravenous injection was demonstrated by means of a fluorescent antibody technique. In addition, a possible direct action of the toxin on heart tissue was suggested by the observation that serum levels of alpha hydroxybutyric dehydrogenase and glutamic oxalacetic transaminase rose immediately after inoculation of the toxin.
- Resource Type:
- Thesis
- Identifier:
- ocm61117251
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hansen, Judith E.
- Description:
- The present study- concerned the quantitative and qualitative comparison of two intertidal benthic algal floras. Data were collected from the experimental area, Ano Nuevo Point, and Pigeon Point the control area, both in San Mateo County California (Figure 1). Ano Nuevo Point is located 6^4- km south of San Francisco, California and .5 km north-east of Ano Nuevo Island. The substrate of the intertidal sampling areas was composed of Miocene cherty shale slabs, Intermixed with mudstone (Brabb, 1970). At a -1.2 ft tide, 250 m of intertidal area were exposed as measured from + 3.4 ft (in relation to mean lower low water, 0.0 ft). The point is partially protected from direct surf action by Ano Nuevo Island. The control site for the study was located approximately 300 m south of the lighthouse at Pigeon Point and 6.5 km north of Ano Nuevo Point. The substrate was composed of Cretaceous siltstone and conglomerate (Touring, 1959)° The composition of this substrate is quite similar to that at Ano Nuevo Point, but differs considerably in age. At a -1.2 ft tide, A-7 m of intertidal area were exposed, as measured from +3.9 ft. The study area was protected from direct wave shock by a 30 a by 15 m rock outcropping on the northern boundary of the sampling area and by Pigeon Point itself. The lack of pinniped hauling-out grounds in the vicinity of Pigeon Point was the only substantial difference between the environments of the experimental and control study sites.
- Resource Type:
- Thesis
- Identifier:
- ocm60247722
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Duris, Kathryn Ann
- Description:
- Considerable evidence links cumulative and sustained exposure to estrogens to breast tumor proliferation. Chemicals with estrogenic activity can bind to the estrogen receptor (ER) to affect downstream signaling of estrogen-responsive genes. Organochlorines (OC) are a class of chemical pesticides that can act as xenoestrogens to disrupt normal endocrine function. Methoxychlor and Toxaphene are two OC pesticides that have been widely used in California. However, the complete molecular mechanisms that connect OC pesticide exposure and breast cancer are still unclear. Experiments show that some members of the orphan nuclear receptor Estrogen Related Receptor (ERR) family interact with the OC pesticides and hypoxia inducible factors to modulate mitochondrial stress response. Mitochondrial DNA transcription is altered by estrogenic and stress signals. The mTOR pathway integrates different cellular stress signals to regulate glucose metabolism, insulin signaling, apoptosis, and cellular detoxification, all processes controlled by the mitochondria. This project investigates how organochlorine pesticides may increase intracellular oxidative damage that changes mitochondrial energy use to favor a cancerous phenotype, and do those changes differ based on Estrogen Receptor (ER) status. To explore this problem I use ER+ and ER- cell lines to evaluate the expression of proteins, and their mRNA, involved in pesticide binding (ERR?, ERR?, and ERR?), oxidative stress (PGC-1?, HIF-1?, -1?, -2?), and mitochondrial function (mTOR, SIRT1, FOXO1).
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Sciutto, James R
- Description:
- There exists among genetic forms the simplest self-replicating biological entity; namely, the "viruses." To define the term "virus" is not easy, for viruses cannot be defined by common-sense criteria the way animals and plants can. The term "virus" was first used by the ancient Roman physicians to denote a poison of animal origin. The diseases caused by such poisons were called "virulent." During the late nineteenth century Ivanowsky found that these invisible infectious agents were much smaller than bacteria. Because they retained their infectivity after passage through a filter able to retard the passage of all then-known types of bacteria, these submicroscopic agents were termed "filterable viruses." The early twentieth century brought with it the discovery that viruses were subcellular entities capable of entering living cells and of reproducing only in such cells. The viruses were thus referred to as "obligate intracellular parasites" whose specific action was at the level of the gene.
- Resource Type:
- Thesis
- Identifier:
- ocm62589640
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Holland, V. L.
- Description:
- The purpose of the present study is to gain some insight into the complex of factors that create the canopy effect with emphasis on the microenvironment that is associated with the vegetative differences. Data recorded weekly included the measurement of plant growth, precipitation, air temperature, soil moisture, and soil temperature. Other studies involved pH, bulk density, permanent wilting percentage, moisture equivalent, field capacity, organic content of the soil and. plant distribution. The determination of all factors involved was not possible in the two growing seasons studied, but accrued data suggests certain ecological relationships. The investigation was undertaken at the San Joaquin Experimental Range (SJER) near O'Neals, California, 25 miles north of Fresno. The SJER is situated on the east side of the San Joaquin Valley in the Sierra Nevada foothills. The natural vegetation is typical of the foothill woodland community (as recognized by Munz, 19&3) consisting of trees 15-70 feet tall in an open woodland with scattered brush and grassland between the trees.
- Resource Type:
- Thesis
- Identifier:
- ocm58723865
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Delmanowski, Robert
- Description:
- Petrolisthes cinctipes and P. manimaculis are two closely related species of anomurans that live in the upper intertidal zone along the Central California coast. Morphometric measurements were collected to gain insight on the reproductive cycles of these species. Ovary weights of P. cinctipes increased from July (0.2 ? 0.1 ?g) to September (18.0 ? 6.0 ?g), remained similar through January (19.0 ? 7.0 ?g), and then decreased in February (5.6 ? 3.0 ?g). Vitellin (Vn), an egg yolk protein, is metabolized from a larger hemolymph protein, vitellogenin (Vg). The Vns of both species were isolated and characterized. Using SDS-PAGE it was determined that the Vn of the conspecifics, P. cinctipes and P. manimaculis, consist of three major subunits that have a MW of 93 ? 2 kDa, 82 ? 2 kDa, and 65.7 ? 1.4 kDa. Two minor bands were also detected at 111 ? 2.3 kDa and 40 ? 1.3 kDa. Using HPLC, the native molecular mass of P. cinctipes vitellin was found to be 301 ? 14 kDa with a small doublet. The native molecular mass for P. manimaculis Vn is 324 ? 11 kDa with a more pronounced doublet of 160 ? 13 kDa. A Western blot was used to test the reactivity of the Petrolisthes Vn with various antibodies. It was revealed that two of the major Petrolisthes Vn subunits, 93 ? 2 kDa and 65.7 ? 1.4 kDa, successfully bound with Homarus anti-Vn antibodies. An ELISA was developed that can measure Vn and Vg in the hemolymph of both Petrolisthes species, with an effective range from 9-3000 ng. There was no difference in mean Vg level from September (240 ? 100 ?g/mL) through January (310 ? 50 ?g/mL), with a total mean Vg concentration of 284 ? 32 ug/mL.
- Resource Type:
- Thesis
- Identifier:
- .b66450883
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Tucker, Vanessa Renae
- Description:
- The goal of this study was to evaluate the population dynamics of small nocturnal mammals and the occurrence of medium to large mammals at Naval Air Station Lemoore in Lemoore, CA and a proposed conservation easement along the Kings River nearby. To assess small mammal activity, trapping grids were placed at three sites from June 2011 to May 2012, and mark-recapture methods were used to estimate populations. Baited camera traps were placed in those sites and at two additional sites, and digital images were used to assess medium to large mammal occurrence. Deer mice (Peromyscus maniculatus) were the most common small mammals captured. Western harvest mice (Reithrodontomys megalotis) and California voles (Microtus californicus) were also captured, but in numbers too small to make population estimates. Populations of deer mice were abundant at the beginning of the study, most likely due to the season and the previous year�s higher than average rainfall. They also experienced a significant decline during the colder months (Oct-Jan), which could be explained by the high metabolic cost of maintaining their core body temperatures. The camera traps were largely unproductive and captured a total of two target species (coyotes [Canis latrans] and red foxes [Vulpes vulpes]) in 1,665 h of trapping. It is recommended that further studies be done to assess the many complex conservation and management issues that still remain unevaluated.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Velázquez, Claudia Cristina S
- Description:
- The aim of this study was to examine the swimming locomotion of the green shore crab Carcinus maenas larvae (stage I zoeae), to investigate the role and mechanics of their swimming appendages. High speed video recordings of swimming and sinking zoeae revealed the kinematics of the whole zoea and its appendages. Analyses of these video recordings for swimming locomotion were performed using MATLAB software and ImageJ. From the body, maxilliped, and natatory setae kinematics and the zoea swimming gait, we found that swimming speed measurements were threefold higher than previously reported in green crab zoeae, and maximum and minimum maxilliped angles were greater than previously observed. We also quantified the flow generated by swimming zoeae using Particle Image Velocimetry (PIV). Analysis of recordings for flow fields was performed using the PIVlab-Digital PIV Tool for MATLAB. We obtained flow velocity and vorticity fields generated during free swimming and tethered zoeae. To our knowledge, this study is the first to report sinking speeds for green crab larvae, maxilliped and natatory setae speeds, and flow fields during routine free swimming and tethered escape responses.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Ingles, Elizabeth
- Description:
- This thesis is the result of a study to determine the importance of geographic and climatic features in the distribution of the mammals of Middle America. Middle America is here defined as Mexico and Central America including the islands that belong to the countries studied. All the Recent mammals with the exception of the order Chiroptera are included in the study. The Chiroptera, or bats, are excluded because, since they alone of all the mammals can fly, geographic and climatic features are not such important ecological barriers to their distribution. Scientific names used in this study are based on Miller and Kellogg (1955). With a few exceptions specific rather than subspecific names are used.
- Resource Type:
- Thesis
- Identifier:
- ocm60405312
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Salas, Hailey Kathleen
- Description:
- Intertidal organisms, like the porcelain crab, regularly experience thermal stress. Petrolisthes cinctipes inhabits the upper-mid intertidal zone and is often exposed to aerial stressors at low tide. Increased abiotic stressors may interfere with many aspects of this organisms’ physiology, including reproduction. Reproductive activity can be measured through the quantification of the yolk protein vitellogenin (Vg), found in hemolymph. ELISA for P. cinctipes allowed for quantification of Vg in hemolymph. Vg sampling of P. cinctipes revealed decreased reproduction around the summer solstice. Reproduction may be dependent on environmental variables such as temperature or day length. To examine this, P. cinctipes were collected monthly for one year. After a pre-treatment hemolymph draw, crabs underwent treatment to test effects of long day lengths and daily exposure to thermal stress. After two weeks of treatment, a second hemolymph sample was drawn. Hemolymph samples were analyzed for Vg levels using an ELISA. Crabs collected near the summer solstice sustained low levels of Vg after exposure to thermal stress. Long day thermal stress conditions caused Vg production to decline in crabs collected during the winter solstice. These data suggest that P. cinctipes relies on multiple environmental cues in regulating reproduction, and changes in environmental conditions could interfere with this physiological process.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Spaulding, Taylor John
- Description:
- Salmon fisheries managers often use models to determine the growth of individuals and populations for a variety of management objectives. Most models of juvenile salmon growth during their freshwater residency only incorporate activity costs for drift foraging when making growth assessments and predictions. I propose that fish may need to include a searching foraging strategy to meet their energy needs under certain situations, such as when prey are scarce, difficult to find, or if low water velocities do not promote high drift delivery. To investigate this I tested how the growth derived from otoliths collected from a cohort of wild juvenile Chinook Salmon (Onchorhyncus tschawytscha) in the San Joaquin River compared to predictions of growth derived from the individual based model inSTREAM. Model predictions of search foraging events were confirmed by stable isotope analyses, which suggested that a significant portion of total consumed biomass was derived from oligochaetes. The model was then used to simulate a variety of discharge and prey production scenarios to investigate their effects on growth and survival. Results from these scenarios suggest that prey production has the most significant effect on growth and survival, while all discharge levels above Critical Low are beneficial for growth and survival.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Bono, Lori Rachelle
- Description:
- Toxoplasma gondii is a ubiquitous zoonotic protozoan parasite, whose infective and environmentally resistant oocyst stages can be transported into fresh and marine waters via freshwater runoff, stormwater discharge and sewer systems. The ingestion of these oocysts, either through direct consumption or through the consumption of filter-feeding marine bivalves, can have a detrimental impact on humans and a variety of marine mammals including the threatened southern sea otter (Enhydra lutris nereis). Terrestrial vertebrates are also susceptible to T. gondii infection since this parasite has a facultative heteroxenous life cycle that potentially includes all terrestrial vertebrates. Ticks (Acari) are known to serve as vectors for organisms that are pathogenic to humans and other animals, and it is suspected that ticks may serve as vectors for T. gondii and could facilitate transmission to terrestrial vertebrate hosts. This study evaluated the prevalence of T.gondii in populations of Pacific coast hard ticks (Dermacentor spp. and Ixodes spp.) and investigated the distribution and abundance of tick species in coastal terrestrial habitats. All ticks (n = 110) within the greater Morro Bay area, California tested negative for T. gondii. A significant difference was found between the number of flagged ticks at different sites and in different seasons. This study was the first to use DNA based analysis to attempt to detect T. gondii in Pacific coast hard ticks.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Jorgensen, Christopher
- Description:
- Anthropogenic activities have severely impacted much of the life on Earth. To protect and preserve our remaining natural areas, conservation biology has traditionally focused on the impacts of humans on natural systems. Recently, conservation biology has incorporated phylogenetic metrics to better understand the evolutionary value of imperiled species. All extinctions include the loss of some biological value, but extinctions of many closely related species result in a disproportionate loss of evolutionary history relative to the same number of extinction events among distantly related species. Mammals are one of the most well-studied groups in phylogenetics, making them ideal candidates for evaluating the loss of evolutionary history that accompanies extinction. I use data collected from a published phylogeny on California’s native terrestrial mammals to investigate the relationships between conservation status, as a proxy for extinction risk, and phylogeny. I examined the potential losses of phylogenetic diversity and disparity by calculating the change in Phylogenetic Diversity (PD) and Net Relatedness Index (NRI) when species with elevated extinction risks were pruned from the California mammalian tree of life. These analyses reveal that the potential loss in PD and NRI is equal to or even lower than expected from a random loss of the same predicted number of species. These results are consistent with global trends for mammals, but show how this global pattern is also present at some regional scales, which is not always the case in previous investigations.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Melkonian, Tamar
- Description:
- Plant Parasitic Nematodes (PPNs) are a challenging problem in today's agriculture causing an annual loss of about 157 billion dollars (Li et al., 2015). Until recently, methyl bromide was the most used agent for controlling PPNs. However, methyl bromide is now not preferred because of its high toxicity (Li et al., 2015). This establishes a problem by losing a way to control these PPNs. In order to effectively kill these PPNs, Dr. Calderón-Urrea's laboratory used Caenorhabditis elegans (C. elegans) as a model organism and identified certain chalcones as effective nematicidal agents (Attar, 2011). Chalcones are organic chemical compounds found to be effective in killing the reference strain used in the ACU laboratory (PD4251) of C. elegans (Attar, 2011). For the purposes of this thesis the PD4251 strain, which contains the green fluorescence protein (GFP), is noted as the reference strain. Currently the lab has found three chalcones, 17, 25, and 30, that are effective in killing the reference strain, and although the mechanism behind the chalcones' mode of action is unknown, research in the lab suggests these three chalcones may target different biochemical pathways in the nematode.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Clark, Jimmy D.
- Description:
- The life history of the many Blapstinus species, some of which are occasional pests of crops (Essig, 1926), is poorly known. Only one species, unidentified, has been reared (Blaisdell, 1926), and this on a media of "leafmould, powdered cow chip and soil." Blapstinus histricus Casey, a common species in Fresno, Fresno County, California, was found suitable for establishing rearing techniques and a life history pattern of itself and for Blapstinus until other species are studied.
- Resource Type:
- Thesis
- Identifier:
- ocm57664783
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Scheidt, Shaynon Travis
- Description:
- Previous experiments show that repetitive DNA makes up a large fraction of the pepper genome and contributes to its three-fold size difference with tomato. Further isolation and characterization of repetitive DNA is needed to achieve a better understanding of pepper�s genetic makeup and the evolution of the Solanaceae genome. A random genomic library was constructed from mechanically sheared pepper DNA. Twenty-seven clones, containing anywhere from 200 to 3000 bp, were sequenced and then were analyzed using BLAST against the DNA sequence databases GenBank, TIGR, and SGN. Sequencing results indicate that over half of the clones matched a repetitive class in at least one database and include a variety of retrotransposon, centromeric, telomeric, and ribosomal sequences. Internal repeat structure was analyzed using MEME and demonstrates that pepper nuclear DNA is made up of many short, interspersed repetitive elements as well as some longer repeats with known function. PCR results indicate that some of these repetitive sub-classes occur in other taxa within the Solanaceae family and beyond.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hernández, Alejandro
- Description:
- Chalcones are aromatic ketones that form the central core for a variety of important biological compounds. Previous research in Dr. Calderón-Urrea’s laboratory showed the efficacy of eight chalcones (1, 16, 17, 18, 19, 22, 25, and 30) to kill Caenorhabditis elegans. The chalcones cause 100% mortality, not only in C. elegans but also the plant parasitic nematode Meloidogyne incognita, at concentrations of 10-4 M (Singh, 2013). Furthermore, chalcones 17, 25, and 30 effectively kill at even lower concentrations (10-5 M). However, the mechanism by which the chalcones kill the nematodes is not known. Previous work, also from Dr. Calderón-Urrea’s laboratory, identified a mutant in the C. elegans strain PD4251 that is resistance to Chalcone 17, and this new mutant strain was named strain RT-Ch17.1.2. Here we set out to identify the DNA sequence responsible for the mutant phenotype of strain RT-Ch17.1.2 using a combination of genetics, whole genome sequencing (WGS), and bioinformatics tools. I identified six single nucleotide polymorphisms (SNPs), corresponding to two genes; these two genes are therefore candidates involved in resistance of RT-Ch17.1.2 to chalcone 17. These two genes are the mitochondrial ribosomal protein large subunit (mrlp-15), and a 5'-to-3' DNA helicase (pif-1). Both of these genes play a role in the proper functioning of the mitochondria, which suggest that the chalcones may target essential elements of the mitochondria to cause lethality in the nematodes.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hernández, Alejandro
- Description:
- Chalcones are aromatic ketones that form the central core for a variety of important biological compounds. Previous research in Dr. Calderón-Urrea’s laboratory showed the efficacy of eight chalcones (1, 16, 17, 18, 19, 22, 25, and 30) to kill Caenorhabditis elegans. The chalcones cause 100% mortality, not only in C. elegans but also the plant parasitic nematode Meloidogyne incognita, at concentrations of 10-4 M (Singh, 2013). Furthermore, chalcones 17, 25, and 30 effectively kill at even lower concentrations (10-5 M). However, the mechanism by which the chalcones kill the nematodes is not known. Previous work, also from Dr. Calderón-Urrea’s laboratory, identified a mutant in the C. elegans strain PD4251 that is resistance to Chalcone 17, and this new mutant strain was named strain RT-Ch17.1.2. Here we set out to identify the DNA sequence responsible for the mutant phenotype of strain RT-Ch17.1.2 using a combination of genetics, whole genome sequencing (WGS), and bioinformatics tools. I identified six single nucleotide polymorphisms (SNPs), corresponding to two genes; these two genes are therefore candidates involved in resistance of RT-Ch17.1.2 to chalcone 17. These two genes are the mitochondrial ribosomal protein large subunit (mrlp-15), and a 5'-to-3' DNA helicase (pif-1). Both of these genes play a role in the proper functioning of the mitochondria, which suggest that the chalcones may target essential elements of the mitochondria to cause lethality in the nematodes.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Storey, Dylan Bobby
- Description:
- Pepper is an economically important crop whose agronomically important phenotypes have been characterized primarily through the use of genetic linkage maps and Quantitavie Trait Loci (QTL) analysis. With the large number of linkage maps available, many reporting QTLs for multiple phenotypes, aggregation of data is an important, but difficult task. In order to aggregate all maps, the development and placement of homologous loci shared between multiple maps is required. This study aims to convert the RFLP markers, whose use has been historically challenging, into markers whose use is technically trivial in order to facilitate integration. Also presented are computational tools to aid in the development of polymorphic markers and the mathematical integration of genetic linkage maps.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Walker, Susan Ingrid
- Resource Type:
- Thesis
- Identifier:
- ocm64179181
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Waterston, Anthony
- Description:
- Evidence suggests that Particulate Matter, PM2.5, exposure in humans leads to respiratory inflammation through an excess of reactive oxygen species (ROS) production initiated by alveolar macrophages. It is unclear which particle components are responsible for the biological response, but certain organic hydrocarbons, such as quinones, and transition metals like copper are of interest due to their ROS-generating, redox-cycling reactions. In the current study, we investigate the effects of ambient PM2.5 samples collected from Fresno and Claremont, California on ROS metabolism in the rat alveolar macrophage cell line NR8383. A microplate-based assay using the oxidant-sensing probe 2’,7’- dichlorofluorescein diacetate (DCFH-DA) was optimized in our laboratory to assess global ROS production in NR8383 exposed to the ambient PM2.5 samples. The goal is to obtain population-level ROS measurements from treated macrophages using a fluorescence microplate reader and flow cytometer. A representative Claremont sample and a Fresno sample were mass-normalized. The cell responses are significantly different from each other, 5.90 ±1.43FU/ μg PM2.5 and 0.86±0.31 FU/ μg PM2., respectively (p=0.05). When the samples were copper-normalized, a significant difference was obtain in cell response. The Fresno sample, 29.87±7.29 FU/μM of Cu sample and Claremont sample, 4.34±1.60 FU/μM of Cu sample (p=0.05).
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Christensen, Norman L
- Description:
- There is a great deal of evidence which suggests that bacteria play many important roles in aquatic communities. Their roles include serving as food sources, uptake of otherwise unusable and sometimes toxic organic substances, biosynthesis of vitamins needed by other organisms, primary production, and the addition to the community of required minerals. However, little work has been done on the types and roles of bacteria in temporary ponds. Works on larger bodies of water indicate that bacteria may be an important food source for much of the zooplankton (Fred, Wilson, and Davenport, 1924; Birge and Juday, 1934; Rodina, 19^9; Welch, 1952). In temporary ponds many zooplankters are filter-feeders. An important criterion for food suitability in these animals is the size of the food (Luck, Sheet, and Thomas, 1931; Burns and Rigler, 1967; Burns, 1968). Bacteria may be filtered by protozoans, rotifers, and crustaceans, while many algal species are too range to serve as food for these organisms. The bacteria may be a more important food source to these organisms than the algae.
- Resource Type:
- Thesis
- Identifier:
- ocm57571688
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Smith, Ryan Michael
- Description:
- Mammalian predators are known to be sensitive to relatively low levels of habitat perturbations, and disturbances to these species are underway due anthropogenic development and climate change in the Sierra Nevada Foothills (SNF) of California. This was the first study to use motion-activated cameras to detect these target species in oak woodland habitat of the central SNF. From February 2014 to February 2015 seven mammalian predators were detected on the Sierra Foothill Conservancy�s McKenzie Preserve at three different elevations: coyote (Canis latrans), gray fox (Urocyon cinereoargenteus), bobcat (Lynx rufus), striped skunk (Mephitis mephitis), raccoon (Procyon lotor), American badger (Taxidea taxus), and black bear (Ursus americanus). Occupancy models indicated that the bobcat, coyote, gray fox, and raccoon were using the preserve with 100% probability, and were widely distributed throughout the preserve. Habitat use was patchy for the American badger, black bear, and striped skunk. Generalized linear models showed interactions between the gray fox, raccoon, bobcat and coyote to suggest coexistence on the preserve is being maintained through resource partitioning and not temporal or spatial separation. This newly established baseline of mammalian predators is informative for future monitoring, management, and development plans in the SNF.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Goodarzi, Athena
- Description:
- Humans who have been exposed to Beta-methylamino-L-alanine (L- BMAA) developed amyotrophic lateral sclerosis Parkinson-dementia complex, (ALS-PDC). The structure of L-BMAA is similar to glutamate, making it a glutamate agonist. Since glutamate is an excitatory neurotransmitter in both insects and vertebrates, Drosophila melanogaster is an ideal model to study the effects of L-BMAA toxicity. Previous studies on fruit flies that ingested L-BMAA showed heterogeneous walking behaviors_some flies were more affected. The research outlined in this thesis studied the acute effects of L-BMAA on the locomotory behaviors of fruit flies (Canton S.) when injected with L-BMAA. The study focused on three main goals: (1) test whether injection is a better method of delivering the toxin than ingestion because it might reduce heterogeneity, (2) quantify the acute effects of injecting L-BMAA on locomotory behavior compared with the effects of more prolonged exposure by ingestion, and (3) search for evidence of sequestration or other coping mechanisms by monitoring flies for evidence for transient effects. Comparison of the two introduction routes resulted in no difference in the observed behavioral changes. Fruit flies injected with L-BMAA did not show any observable transient effects. However, this thesis project was able to shed light on the possibility of a sequestering mechanism in fruit flies to control for L-BMAA intoxication.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Lee, Kwok Wah
- Description:
- The generic name Chlorococcum appears frequently in reports of soil flora investigations, but there is a marked lack of agreement regarding the circumscription of organisms to which this genus name applies (Starr, 1955). Furthermore, there is confusion as to the limits of the species comprising this group. This disagreement may partly be explained by the fact that the greater number of the species of Chlorococcum were described before 1900 by investigators who studied algae only from mixed collections in nature. The intensive study of Starr (1955) on Chlorococcum and other spherical, zoospore—producing genera of the Chlorococcales laid a firm foundation for the taxonomy of this venus. The three most consistent characteristics which are in occurrence and tend to group the species in putative natural alliance are: the type of zoospore, the type of chromatophore in the vegetative cell and one presence or absence of a pyrenoid in the vegetative cell. The genus Chlorococcum is differentiated from other genera in the Chlorococcaceae by its possession of three constant attributes: (l) asexual reproduction by means of Chlamydomonas type zoospores, (2) vegetative cells with a parietal, hollow spherical chromatophore and (3) vegetative cells with at least one pyrenoid (Starr, 1955). The importance of each as a taxonomic criterion at the generic level is fully discussed by Starr (1955). The zoospores of all species of this genus constantly retain their shape when becoming quiescent; all possess two flagella of equal length. Recently in classifying the taxonomically difficult unicellular algae, phycologists have found it necessary to resort to morphological descriptions together with certain physiological characteristics, such as hydrogenase activity, gelatin liquefaction, secondary carotenoid synthesis and the growth responses to various carbon and nitrogen sources (McLean, 1968). Bold and co-workers (Brown and Bold, 1964); Chantanachat and Bold, 1962; Mattox and Bold, 1962; Smith and Bold, 1966) have employed nutritional requirements, utilization of various carbon and nitrogen sources, growth in light and dark, ability to reduce nitrite, antibiotic reactions and immunochemistry to supplement the attributes of species in several Chlorococcacean genera. McLean (1968) measured the total chlorophyll and carotenoid concentrations in relation to total pigment content for eighteen Chlorococcum isolates which were grouped according to the color of the culture incubated under defined conditions for 6-7 weeks. He suggested that pigmentation of old cultures be used as the first criterion for distinguishing species of Chlorococcum. Comparative ultrastructure studies have also been utilized to supplement the microscopic morphological attributes. Gibbs (1962) employed the ultrastructure of the pyrenoids in the taxonomy of green algae above the generic level. Brown and Bold (1964) were the first to separate species of Tetracystis by comparing the ultra-structure of chloroplast, pyrenoid, mitochondria, Golgi apparatus and cell wall. Recently, Brown and McLean (1969) on the basis of studying the fine structure of pyrenoids in eighteen Chlorococcum species proposed three differentiating categories: (l) pyrenoids with unfragmented perforate starch plates, (2) pyrenoids with many separated fragmented starch plates, and (3) pyrenoids with hemispherical unfragmented starch plates. Pyrenoids were further distinguishable on the basis oi the number of thylakoid disks or tubules which penetrate the ground substance. The objectives attempted in this study were three-fold: to compare the morphology of six different species of the genus Chlorococcum growing on six different media under defined culture conditions, to determine any diagnostic physiological characteristics helpful in the separation of these species, and to examine and study the cell wall ultras ultrastructure of each. It was intended that such data might provide additional information for the separation of the species under investigation, and hopefully, the principles might be applied to the classification of other microalgae.
- Resource Type:
- Thesis
- Identifier:
- ocm60587395
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Friedlein, Jordan Bradley
- Description:
- The Bcl-2 protein family, made up of pro and anti-apoptotic proteins plays a major role in regulating apoptosis. Bax is a pro-apoptotic member of the Bcl-2 family. In its inactive form, Bax is primarily a cytosolic and monomeric protein. Upon activation, Bax translocates to and permeabilizes the mitochondrial outer membrane releasing apoptotic factors. Because Bax plays such a pivotal role in cell death signaling, it is highly regulated through interaction with protein kinases and other members of the Bcl-2 family. Activation of Bax also requires a substantial change in conformation and of localization of the Bax protein, exposure of the N-terminus is one such conformational change Bax undergoes. However, the molecular processes linking N-terminus exposure with respect to Bax’s ability to translocate to, insert, and permeabilize the mitochondrial membrane remain to be defined. When Bax mutants P168A and S184A are expressed in yeast, they have higher mitochondrial localization than WT Bax. However, The S184A mutant is far less capable than P168A or WT Bax in releasing cytochrome c, a step considered to be the point of no return in the apoptotic signaling cascade. By using an ELISA to probe the recombinant Bax mutants for N-terminus exposure, we found significantly lower levels of N-terminus exposure the S184A when compared to P168A or WT Bax, suggesting that the N-terminus plays a more predominant role in pore formation than mitochondrial localization. However, the mechanism by which the N terminus increases the pore formation ability of Bax has yet to be defined.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Walker, Howard R
- Description:
- Nemacladus Interior has an eight-nucleate, Polygonum type of embryo sac which forms a haustorial process at its chalazal end. This process invades and crushes part of the chalazal tissues of the integument. Fertilization takes place within twenty-four hours after pollination. All nuclei except the zygote nucleus and the primary endosperm nucleus break down before or immediately after fertilization. During embryo sac development, an endothelium is differentiated around it. This endothelium forms a protective layer outside the endosperm in the mature seen. The endosperm is cellular from the beginning. I^s development is characterized by a transverse division of the primary endosperm nucleus followed by a longitudinal division in the primary micropylar chamber and a transverse division in the primary chalazal chamber. The mature endosperm cells have thick walls and contain oi1. Two endosperm haustoria are formed—a large two-celled micropylar haustoria and a small, single-celled chalazal haustorium. The zygote elongates during early stages of endosperm development but does not divide at this time. The development of the embryo generally follows the Solenad type.
- Resource Type:
- Thesis
- Identifier:
- ocm64180164
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Shiglik, Alexander
- Description:
- Insects of the higher Neoptera flap their wings by an asynchronous mechanism: Wing strokes are not individually triggered by nerve impulses; rather, delayed stretch-activation allows the flight muscle to oscillate spontaneously when coupled to a resonant load. This type of ‘distributed’ control mechanism has obvious advantages such as neurological economy and robustness against perturbation, but the implications have not been fully explored. Previous researchers have found only that asynchronous flappers are constrained to a narrow frequency range. We have constructed mathematical and mechanical models of delayed feedback oscillators that display additional complex dynamics which have not been observed in insects. I used audio and high-speed video recordings of blue bottle flies to investigate the further consequences of asynchronous flight control. By mapping the dynamical parameter space displayed by a real insect, I concluded that the delayed feedback oscillator mechanism is indeed sufficient, despite my data suggesting that there is no simple harmonic motion and that no elastic forces act in the wing system of the flies. However, I believe this counterintuitive data is caused by brief periods of anharmonicity at the upper and lower extrema due to the elastic components’ increased stiffness, resulting in an overall higher frequency, and not because the flies abandon the mechanical oscillator scheme altogether.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Moe, Louis Maynard
- Description:
- In nature, seeds are often exposed to high, temperatures. This may occur while seeds are still attached to the parent plant or after they have fallen to the ground and are exposed to intensive thermal radiation. Levitt (1956) indicates that soils exposed to direct sunlight may reach temperatures as high as 65 to 85°C, depending on soil type. In regions in which fire is an important factor in the environment, many seeds must sometimes tolerate extremely high temperatures if they are to survive. Sampson (1944) measured soil temperatures during a fire. Maximum soil temperatures in dense annual grass and manzanita was 515°0 at a depth of one-half inch, and 100°C at one and one-half inches. Stone (1951) demonstrated that a soil temperature of 12000 lasting for more than five minutes resulted in total seed destruction.
- Resource Type:
- Thesis
- Identifier:
- ocm61123987
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Single, Alexander
- Description:
- The northern black swift (Cypseloides niger borealis) is an insectivorous bird that nests in small colonies in western North America. The black swift is a California Species of Special Concern with a statewide population estimate of 200 pairs. Previous research has mostly focused on nesting locations, whereas foraging habitat is largely unresearched due to the difficulty of detecting foraging black swifts. We conducted surveys for black swifts in the southern Sierra Nevada. We collected data from 67 potential nesting sites on six aspects of black swift nesting microhabitat: water flow, vertical relief, aerial access, shade, nesting niches, and moss cover. We collected additional data from surveys in Colorado for a total of 109 observations in California, Colorado, and New Mexico. We used the proportion of standing water and wetlands within four concentric rings extending from each colony as an index of foraging habitat quality. Water and wetlands are a major source of emergent insect prey. These scores were used as independent variables to determine their relative effect on the occurrence of black swifts at each site. We located a total of nine black swift colonies in California, three of which were previously unknown. Our results indicate that foraging habitat is a more influential driver of nesting site selection than microhabitat and water was the most significant subcomponent of microhabitat. We exercise caution in our interpretations due to our small sample sizes.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Wong, Margie
- Description:
- Immunochemical studies on nucleic acids began in the late 1950's. Prior to that time, there were no conclusive data that nucleic acids were immunogenic. Lackman and co-workers (42) reported data that were suggestive of reactivity of deoxyribonucleic acid (DNA) with antibacterial sera, but his results were believed to be due to nonspecific interactions. In the late 1950's and the early 1960's, researchers began using with success nucleic acid-rich preparations as immunogens. Antibodies specific for DNA were produced when rabbits were immunized with a DNA-rich preparation derived from Brucella abortus (57, 67, 71), with killed gram-negative bacteria (16), and with nucleic acid-rich preparations from animal sources (17, 47, 55).
- Resource Type:
- Thesis
- Identifier:
- ocm64200917
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Galentine, Steven Paul
- Description:
- The objectives of this study were to determine the gastro-intestinal and ectoparasite prevalence and intensity of infection in five species of medium-sized peri-domestic mammals captured in immediate proximity (3.05 m) to structures. These mammals (n=57) were collected throughout urban Stanislaus County, California from December 2006 to August 2007. Baylisascaris procyonis nematodes, causes of serious neurological pathogenesis in humans, occurred in 75% of raccoons (n = 20), with a mean intensity of 16.8 nematodes/raccoon. The raccoons also harbored fleas and ticks with known pathogen vectorial capacity. Additionally, 13 striped skunks, 14 Virginia opossum, 9 gray fox, and 1 red fox were evaluated similarly. Rates of prevalence and intensity of infection of gastro- intestinal parasites and fleas and ticks from the other mammals were calculated. No previous study has provided parasite data on these mammals in central California. The values for prevalence and intensity of the parasites, particularly B. procyonis, are of significant public health concern where direct or indirect contact with humans and domestic animals is likely.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Arevalo, Erik
- Description:
- Organisms that rely on vision for navigation through their environment often do so by integrating many visual cues in order to guide themselves to their desired goal. In ants, research has identified a number of visual cues and features that guide an ant when navigating; however, how the objects are perceived or prioritized in a natural environment is unknown. One gap in the research is how ants, when there are several visual objects, extract different visual features and subsequently how these cues are behaviorally weighted. The ability to weigh the relevance against one another would allow the ants to prioritize a specific visual object or combination of the objects that can maximize their ability to reach a goal. In order to address this gap in knowledge, a model has been developed that explores how an ant can use different cues or combination of cues to facilitate navigation. To test our model, a combination of simulated and camera-imaged environments were examined during the initial random forging walk to locate a food source and a subsequent walk from nest to food site. Specifically, we have taken views from an ant’s visual perspective and processed these views using an image processing algorithm that extracts the geometric features, such as peaks, edges and centroids, that ants are known to use to guide their routes. As an ant progresses through the environment on its first random walk, features were extracted and only these features were stored in a “memory matrix” representing the sum total of features experienced during the walk. To test the value of the cues stored during the random walk, a second walk was performed from nest to food source. On the second walk ants would take a “snapshot” of their current view and extract the visual features. These features were then compared to the sum total of features stored in the “memory matrix” using pixel matching. The results from both the field studies and simulations suggest that in order to have the most robust success in foraging within the model, a global cue is necessary to allow the ant to get within the proximity of the goal and then they should switch to a local cue, which allows for more precise localization of the goal. Ultimately the work done here has allowed us to understand how visual information is prioritized and perceived as well as potentially expanding on how to increase the efficiency of cognitive processes such as memory storage and efficiency.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Adineh, Shadi
- Description:
- In most species, mitochondria are maternally inherited. Work in Caenorhabditis elegans has shown that a cellular surveillance system eliminates sperm-borne mitochondria that enter an oocyte. Such a system might have evolved to prevent heteroplasmy (the presence of multiple mitochondrial genotypes in a cell), which can result in mitochondrial disorders. However, in C. briggsae hybrids, repeatedly backcrossing female hybrids to parental males has been suggested to result in paternal mitochondrial transmission. Observations in other taxa have also shown that hybridization increases paternal mitochondrial transmission, raising the hypothesis that hybrid genotypes cause the surveillance system to malfunction and thus facilitate the increase in paternal transmission. This hybrid dysfunction might occur because of recombination of unknown strain-specific molecular signals of paternal mitochondria and their unknown maternal receptor molecules. My objective was to compare the frequencies of paternal transmission in C. briggsae hybrid and control crosses. In twelve novel hybrid lines, all showed preliminary evidence of paternal mitochondrial DNA, although no firm conclusion can be reached as to whether this occurred via paternal mitochondrial transmission. Future work will be needed to unequivocally demonstrated whether paternal mitochondrial transmission occurs, and then to identify the genetic architecture of the quality control system responsible for paternal mitochondrial elimination.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Perry, Gladys Mae
- Description:
- Periodically among animals is but single phase of community organization. As a result of this cyclic behavior more complete utilization of the habitat space and radiant energy within a community is possible. Each community is characterized by a diel pattern of activity divided into two complementary portions (day and night), each of which contains an active and inactive fauna. It is the purpose of this study to investigate the diurnal periodicity of the Belding Ground Squirrel (Citellus beldingi, Fig. 3), and the Yellow bellied Marmot (Marmota flaviventris, Fig. 5). And to correlate the physical factors of light intensity and temperature to these activity patterns inasmuch as it seemed justified with inadequate data available. Study began on the twenty-first of June, 1951 and continued through the month of July of the same year.
- Resource Type:
- Thesis
- Identifier:
- ocm61682215
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Booth, April Meiyee
- Description:
- Alzheimer’s disease (AD) is the most frequently encountered form of dementia. Research in mammalian model systems and clinicalstudies in humans indicate that caffeine in the diet can decrease the frequency and severity of Alzheimer’s disease. The effects of caffeine on Alzheimer’s pathology in the more basic model organism, Drosophila melanogaster, have not been extensively studied. We evaluated the effects of caffeine in the diet of Drosophila expressing the early stages ofa pathology common in Alzheimer’s, tau pathology. We measured and compared the effects of the neuropathology by characterizing deficits in learning and memory in Drosophila expressing human tau that were fed caffeine versus those that were not. We also tested the longevity of the flies expressing tau pathology that were exposed to caffeine versus none. To assess behavioral decline,a spatial behavioral assay was used to quantify deficits in spatial learning memory. It was found that Tau flies lived longer than even wild type, UAS and Gal-4 line controls. Tau flies not exposed to caffeine also lived longer than Tau flies exposed to caffeine. The preliminary spatial memory data indicates that caffeine exposure could aid in short-term memory formation. This work could support the use of Drosophila as a high-through put system to study behavior and the underlying neural deficits associated with AD.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Potter, Gary W
- Description:
- During the past forty years, several papers have appeared in the literature discussing various aspects of water conservation by desert inhabiting rodents, Howell and Gersh (1935) reported that kangaroo rats (Dipodomys) are able to survive on a diet of dry seeds without drinking free water, in spite of the high diurnal temperatures and low relative humidity of their natural environment. A more extensive study of water metabolism in desert inhabiting species of kangaroo rats by Schmidt-Nielsen and Schmidt-Nielsen (1951) has shown that both behavioral and physiological adaptations are Involved in the conservation of water by Dipodomys. with the most important adaptation being the ability of these animals to produce a highly concentrated urine, thus retaining more water within the body. The kidneys of desert inhabiting kangaroo rats have thus been shown to be much more efficient in the use of water for the production of urine than kidneys of mammals from mesic and aquatic habitats. In attempts to correlate the structure of kidneys to this physiological adaptation for water conservation, Sperber (19^) and Schmidt-Nielsen and O'Dell (1961) have made measurements of the gross structures of kidneys of mammals from varying environments and correlated the measurements with physiological studies of urine concentrating ability. These investigations have shown that the kidneys of desert inhabiting rodents such as Dipodomys and Psammomys have a wider medulla and produce urine of higher concentration than the kidneys of species normally inhabiting mesic and aquatic environments. The wider medulla of the desert inhabiting species allows the nephron tubules to extend a greater distance into the medulla of the kidney, causing the intratubular material to travel a greater distance, thus allowing the counter current multiplier system of the kidney to remove a relatively greater amount of water from the intratubular material and return it to the body.
- Resource Type:
- Thesis
- Identifier:
- ocm61741056
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Boreham, Melvin M
- Description:
- The immature stages of six species of Cnepfaia were found by the author lin the streams of the central Sierra Nevada mountains. Of these only Qnephia mutata (Hallooh) and C, stewarti Coleman hare been reported previously from California* Cnephia jeaaae QeFoliart and Peterson is known from Utah and Wyoming, aid the remaining three species were undescribed. The larvae and pupae of the six species are described, and a key for their identification is provided. The adults of C. minus (Dyar and Shannon) and C. osborni (Stains and Know!ton) have been reported to occur in California but their immature stages are not known.
- Resource Type:
- Thesis
- Identifier:
- ocm57194094
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Polineni, Venu
- Description:
- Meloidogyne incognita (Mi) is a root knot nematode that infects various commercial crops and accounts for a crop loss of $100 billion a year worldwide. Therefore, learning about the biology of this parasite may help develop new strategies for its control. This study was focused on: ( i ) learning about the early development of Mi (up to the 16 cell stage) (ii) establishing protocols for generating transgenic Caenorhabditis elegans (C. elegans) lines using the microparticle bombardment method, and (iii) attempting to generate transgenic Mi lines by using the protocol developed for C. elegans in our laboratory. As markers for transformation using the microparticle bombardment system we used two constructs developed to monitor cell development in C. elegans: 1) two constructs with a muscle promoter fused to the green fluorescent protein (GFP); and 2) a construct with a neural promoter fused to the red fluorescent protein (RFP). Once we established transformation protocols in C. elegans, we generated 7 GFP containing lines and 5 RFP containing lines. The protocols were also used to shoot galls of Mi to determine if the constructs would express the reporter gene in the J2 state of Mi. After 3 experiments we obtained 5 J2 worms expressing GFP and 5 worms expressing RFP suggesting that our protocols can be used to generate transgenic Mi lines and that the constructs are suitable for expression in Mi.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Anderson, Jordan Jill
- Description:
- Animals are constrained by the urban landscape as human population density and building density impinge on the distribution and abundance of various species. This study used transects and citizen science observations to determine the distribution patterns of the local squirrel species Sciurus niger and Otospermophilus beecheyi. Sciurus niger were primarily distributed in the central, western, and northern regions of the Fresno Clovis Metropolitan Area. Otospermophilus beecheyi were primarily distributed along the northern, southern, and western edges of the study area. This study examined the habitat use of S. niger by identifying all trees and shrubs, and estimating cover class and utility cable density. This study also aerially digitized cover categories and included housing data from Zillow as well as socioeconomic data. Two socioeconomic variables were significantly positively correlated with squirrel presence; the average household size and the average family household size (Logistic fit: R2 = 0.054, P < 0.0225; and R2 = 0.057, P < 0.0184; respectively). This study examined the foraging behavior of S. niger using Giving-Up Density experiments (F (habitat)1, 163 = 19.86, P = 0.0001). As metropolitan areas grow, the sustainability of the urban landscape of local flora and fauna becomes an increasing concern. Even though squirrels are considered pest species, increased understanding of their ecology should govern appropriate management decisions.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Huddleson, John H.
- Description:
- The benefits of fertilizing farm ponds are well known. For example, Swingle and Smith (1941) found production of fish could be doubled at a reasonable cost by providing a supplemental energy source (commercial fertilizers and cottonseed meal). An additional benefit ascribed to fertilizing ponds is a decrease in rooted aquatic plants as a result of nutrient competition from plankton blooms. But the use of a fertilizer can be an expensive, wasteful process If none of its ingredients is the factor limiting plankton growth. Further, additions at the wrong time, or of the wrong amounts, can do damage. Most commercially prepared fertilizers are made up of various percentages of nitrate, phosphate and sulfate. However, in many instances adding other chemicals such as manganese (Henderson, 1949), molybdenum (Goldman, 1960), and silicate (Ryther and Guillard, 1959) has increased plankton populations. Ryther and Guillard also found one or more components of their iron and trace mineral mixture increased plankton in sea water. Because of these problems, I undertook this research to determine: 1) the changes taking place in plankton abundance and species composition with time, and 2) some of the potential causes of these changes, especially nutrient additions.
- Resource Type:
- Thesis
- Identifier:
- ocm60248661
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hansen, John C.
- Description:
- The chemical composition of sea water has been described as being relatively constant with respect to the ratios of the major components (Dittmar, 1884). There are, however, certain of the minor constituents of sea water which are less conservative and may vary substantially with time and location. There are a number of physical factors related to water movement which affect the concentrations of minor constituents, but major fluctuations ultimately result from biological processes (Harvey, 1966). Two of the minor sea water constituents which display large variations in concentrations are the compounds of nitrogen and phosphorus. Since these compounds are also major plant nutrients, their concentrations in sea water can indicate the degree of fertility of the water. Brandt (1899) was among the first to suggest that, with reference to "Liebig's Law of the Minimum," the growth of marine algae in the euphotic zone is often limited by the availability of nutrients, especially nitrogen and phosphorus. Brandt's suggestion has since been well substantiated by Harvey (1928, 1940), Cooper (1933). Chu (1949), and others.
- Resource Type:
- Thesis
- Identifier:
- ocm60247677
- Campus Tesim:
- Fresno
- Department:
- Biology
77. Regulation of methyl farnesoate during the life history of the tadpole shrimp, Triops longicaudatus
- Creator:
- Gledhill, Michael Ray
- Description:
- Methyl farnesoate (MF) is a terminal effector in crustaceans but is the immediate precursor to Juvenile Hormone III (JH) in insects. The insect JH model is well established and is commonly used for comparison with MF functions in crustaceans. MF and JH have two primary effects; to inhibit the differentiation of adult structures maintaining larval morphology, and to enhance reproduction in adults. MF is degraded by MF esterase (MFE). Studies in insects maintain that the rate of JH degradation is inversely related to JH titer. However, there exist no comprehensive studies of MFE activity in crustaceans. Previous studies have demonstrated that dietary MF administration on the tadpole shrimp, Triops longicaudatus (Crustacea: Branchiopoda), will delay gonad growth and oocyte development. We have assayed the rates of MF degradation by MFE throughout the life history of the tadpole shrimp, as well as following the administration of dietary MF. We have found that MFE levels are low in young juveniles but rise near maturity, supporting the function of MF as a juvenilizing factor in this organism. In adults, we find that MFE is inversely correlated with reproductive output supporting the function of MF as an enhancer of reproduction. Dietary MF suppressed MFE rates in late juveniles supporting the observed physiological effects of previous studies, as well as suggesting that the tadpole shrimp does not develop resistance to dietary MF.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Nwangwu, Anthony Chidiebere
- Description:
- In 2013 there were approximately 250,000 acres of pistachios (Pistacia vera L.) grown in 22 counties throughout California. Many of these orchards are planted primarily with male P. vera ?Peters?, and female ?Kerman? trees. In recent years, growers have observed spatial and temporal variation in growth and fruiting density in these orchards. Field analyses of Fresno State?s pistachio orchard confirmed the presence of such phenotypic variations. These may be due to the prevailing environmental conditions, rootstock variability, or perhaps random mutagenesis that occurred during scion clonal propagation over the past 50 years. The objective of this study was to examine the latter possibility as the presence of superior/inferior ?Kerman? trees is not well documented. Total genomic DNA were isolated using either the CTAB method or QIAGEN DNeasy ? Plant Mini Kit and compared. The concentration and purity of isolated DNA products were analyzed using Nanodrop 2000 spectrophotometer. The method of Williams et al. (1990) was used for RAPD-PCR reactions with minor modifications. PCR products were stained with the novel nucleic acid stain GelRed. The advantages of the Kit over CTAB method were observed through the purity index ratio (A260/A280). The purity index ratio for DNA products isolated using either method were significant (P? 0.05). Three out of the seven RAPD primers that were screened revealed strong reproducible polymorphic fingerprints. A total of 72 scorable bands were produced, with an average of 24 bands per primer, of which 40 bands (53.7%) were polymorphic.
- Resource Type:
- Thesis
- Identifier:
- .b6588274x
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Lange, Anthony P.
- Description:
- Bumblebees are able to obtain information both through personal experience and from their conspecifics, but it is unknown if bees are capable of making the best decision when social information conflicts with personal information. Recent research has suggested that bumblebees are capable of communicating complex information, a prerequisite for decision making in a social context. Bees were presented with an arena where the values of food resources were controlled by altering the sugar concentration within artificial flowers and the pollen distribution of natural flowers. The foraging patches that bees chose and the subsequent foraging choices the bees made after social information was acquired was monitored to evaluate the transmission of information. The change in behavior provides insight into what drives a bee’s foraging choices following new information and provides a framework to investigate how bumblebees evaluate and utilize social information that may conflict with their personal information. In response to changes in floral distribution, bees were found to spend more time on foraging trips to higher quality clusters, as well as visiting said clusters with a higher frequency. While the differences between the two feeders were not always significant, a pattern was clear. The lack of consistent significant changes in feeder visits and changes in trip duration could possibly be explained by the small distances at which the experiment took place.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Tamayo, Rachel
- Description:
- Plant Parasitic Nematodes (PPNs) cause an enormous annual monetary loss (Li et al., 2007). Thus, new and safe alternatives to control PPN are needed. Previous work identified two organic chalcones, Chalcone 17 and Chalcone 25, as effective nematicidals (Attar et al., 2012 and Calderón-Urrea, personal communication); however, their mechanism of action is not known. This lack of knowledge is addressed by investigating whether or not there is a genetic pathway that enables C. elegans to overcome the lethal effects of chalcones. We hypothesize that susceptibility to chalcones is due to the action of the chalcone on a protein product, and therefore mutations on the gene encoding that protein will render the chalcone action ineffective. Identifying and isolating mutants was accomplished by screening mutagenized C. elegans for survivors in the presence of chalcones and then testing survivor nematodes for the presence of transmissible chalcone-resistance mutations. We identified two putative resistant mutants with Chalcone 17 and seven putative resistant mutants with Chalcone 25. Then, we determined that we had uncovered two recessive mutants resistant to Chalcone 17 and six dominant mutants and one recessive mutant resistant to Chalcone 25. Further analysis will identify the DNA sequence involved with the mutation using a whole genome sequencing (WGS) approach. Our work will contribute to the understanding of the chalcones’ mechanism of action in killing the nematodes.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Follen, Nate
- Description:
- The poplar tree (Populus trichocarpa) has a strong capacity for growth in regions with high salt and trace element contamination in the soil. Using DNA from three salt/boron tolerant and six sensitive genotypes of poplar, association linkages are discovered between DNA markers and the polygenic trait of salt/boron tolerance. A set of 82 primer pairs was developed from previous research, flanking SSR (simple sequence repeat) regions on 18 of the 19 poplar chromosomes. Microsatellites from each of the nine poplar clones were amplified and detected using polyacrylamide gel electrophoresis. Scoring the markers for size polymorphism between accessions revealed SSR markers linked to the tolerant/intolerant phenotype. Polymorphism data allowed inference of relatedness of the accessions based on genetic similarity, as well as better characterization of SSR polymorphic frequency in the poplar genome. Mapping the markers on the poplar genome gives insight as to salt/boron tolerance-contributing regions of the genome. Using the results, a map of 12 microsatellite markers that are linked to salt and boron tolerance in poplars was established, which could prove to be an effective screening method to identify additional tolerant poplar accessions. Microsatellite regions analyzed were nearly all polymorphic (95.5%), showing no correlation between SSR location and polymorphism rate. Use of polymorphic microsatellites allowed genome wide analysis of genetic elements linked to salt/boron tolerance in poplars.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Mekdara, Nalong
- Description:
- L-Glutamate controls insect locomotion both at the level of the peripheral and central nervous system. _-N-methyl-amino-L-alanine (BMAA) is considered a glutamate agonist that can cause changes in locomotory behavior of Drosophila melanogaster. Overstimulation of glutamate receptors at the neuromuscular junctions should result in loss of motor ability. Overstimulation of the glutamate receptors in the central pattern generator of the central nervous system should lead to hyperactivity (increased activity levels and walking bout duration). Flies were fed high concentrations of glutamate or BMAA (concentrations: 0, 12.5, 25, 50 mM), and their locomotory behaviors were quantified for three consecutive days using two types of assays: the tap-down assay and an assay custom-designed for this study. The tap-down assay records the flies_ climbing up a vertical incline (90_) after the tap-down (climbing in response to an external stimulus). The custom-designed assay (lenticular arena assay) uses a concave floor to quantify spontaneous climbing up a gradually increasing incline (0-15_). It also allows quantification of walking speed, walking bout duration, walking bout frequency, stumble frequency and climbing ability in order to assess locomotory changes in treated flies. The flies showed a dose-dependent response to BMAA, manifesting hyperactivity at low doses and loss of motor ability at high doses. The introduction of excess glutamate caused no significant changes in locomotory behavior.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Naman, Dorothy Johnson
- Description:
- The variability of the phagocytic action has been known for nearly half a century. first being shown clearly by Shattock and Dudgeon (1908). Experiments by Dixon and McCutcheon (1938) were designed to show whether bacteria chemotropically attract leucocytes directly. or only indirectly as the result of injuring cells and tissues, and causing these to liberate chemotropic substances. The results showed that leucocytes may react chemotropic ally to substances given off directly by bacteria. As the leucocytes would migrate across a zone of cell-free plasma towards the bacteria, there was a definite indication that leucocytes react chemotropic ally to substances given off directly by bacteria and not to substances from injured tissue cells.
- Resource Type:
- Thesis
- Identifier:
- ocm61331866
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Hensley, Chris
- Description:
- Researchers have attempted to make generalizations about how species with similar traits respond to urbanization, although results are geographically idiosyncratic. I present a comparative study in three cities in the arid southwestern US: Fresno, CA; Tucson, AZ; and Phoenix, AZ. These three cities share similar climates and biogeographical contexts, but differ in other ways, particularly in levels of urban water use. With presence-absence data, I tested how the urban avian assemblage of each city is filtered from the regional avian assemblage on the basis of traits and phylogeny, and if urbanization causes biotic homogenization among avian assemblages. Results show evidence for trait-based filtering in certain key traits, but not in phylogeny. While prior studies have suggested that urban avian assemblages are determined by species’ traits, our results indicate urban occurrence is likely due to a combination of neutral and deterministic processes. I propose that similar trait-based results in the three cities result from structural similarities in surrounding natural habitats, but that differences in relative urban species richness and report frequency are results of (1) intensive agriculture and (2) a more mesic urban habitat due to urban irrigation contrasting with arid matrix habitats in Fresno. The relationship between urban habitats and the surrounding habitat matrix influences the urban environmental filtering process, and that urban habitats should be designed to closely match natural habitats in order to harbor more native species.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
85. Bird richness and abundance as affected by social-ecological characteristics in an urban environment
- Creator:
- Garcia, Pedro
- Description:
- Several studies have shown that products of urban development have an impact on the behavior and ecology of animals. Urban bird communities have been shown to have greater densities, but often lower diversity compared to their surrounding wildlands, however the underlying drivers behind this difference are not fully understood. This study focuses on three ecological factors mirrored in the natural environment: ambient (urban) noise, greenscapes (city parks), and wetscapes (groundwater recharging basins), as well as a fourth socioeconomic factor: property value. Within a GIS framework, we analyzed bird species richness (total number of species) and abundance (total number of birds) in the Fresno-Clovis Metropolitan Area (FCMA) to test how each of these are influenced by the socio-economic and environmental attributes in both the local and landscape levels. Local-level factors were shown to be initial key components in determining bird species richness and abundance, followed by landscape-level features. Further, property value was found to be a key component when comparing alternative multivariate models. Urban ecological research as well as policy and planning must take more multi-level, multivariate, landscape-based, and taxon specific approaches to understand and better manage urban spaces to maximize biodiversity.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
86. Colonization of Hypogastrura manubrialis Tullberg (Collembola: Poduridae), with notes on the biology
- Creator:
- Vail, Patrick Virgil
- Description:
- To overcome these problems, investigation of the colonization of a Collembolan species on a strictly artificial habitat for an extended period was undertaken stressing methods which allowed ease of maintenance awri observation, whereby notes on the biology could be made as the colonization progressed. Particular attention was given to those aspects of the biology that would aid in evaluating the success or failure of a colony. Hyppga strura manubrialis, because of its ready availability, was chosen for the study. Information concerning the biology of H- manubrialis was obtained on the number of eggs laid, egg fertility of the natural population, incubation period of the eggs, reproductive potential, life expectancy under starvation and general notes.
- Resource Type:
- Thesis
- Identifier:
- ocm63260003
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Miller, Laura Louise
- Description:
- The purpose of this study was to evaluate presence of heartworm antigen in domestic dogs in Madera and, for the first time, Fresno Counties and test for the effects of habitat and other environmental variables on prevalence. Dogs were screened for heartworm via PetChek� ELISA from blood samples (N= 519) collected at seven sites during April-July 2009. Eighteen dogs were heartworm antigen positive. Pearson Chi-square analyses were run on the presence of heartworm versus the following variables: elevation range, percentage of time spent outdoors during the day, percentage of time spent outdoors during the night, pet coat length, weight class, prevention status, and sex. Dogs that spent at least 50% of their time outdoors during the day were significantly more likely to have heartworm that those who spent less time outside (N = 519, df = 1, p = 0.031). Overall prevalence (3.47%) was lower than expected with Madera County having 3.8% positive samples and Fresno County 3.5%; this prevalence is lower than many previous studies. The effect of time spent outdoors on heartworm prevalence was similar to previous studies. The effect of elevation, though not significant, requires further investigation, as does the prevalence of larval stages in mosquitoes.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Crossman, Keith V
- Resource Type:
- Thesis
- Identifier:
- ocm57497206
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Schleder, Bradley Wayne
- Description:
- The availability of water is arguably the most important landscape factor, particularly in arid climates. Homeowner decisions regarding irrigation are likely to have a direct effect on bird species richness. Previous research has suggested a link between socioeconomics and urban species diversity. This empirical study examines a potential pathway for this relationship: Neighborhood socioeconomic status influences residential irrigation intensity, which influences plant cover, in turn influencing bird diversity. This study uses results from the Fresno Bird Count, a citizen science project, along with socioeconomic, vegetative, and irrigation data. Both bird species richness and foraging guild richness were examined. Irrigation intensity decreases in areas with greater poverty levels (P<0.0283). A multivariate model links avian species richness with poverty levels, irrigation intensity, and amount of vegetation (Whole model R2=0.682, P<0.0008). Guild richness decreases in areas of greater poverty levels (R2=0.216, P<0.0042) and less intense irrigation (R2=0.131, P<0.0303). In a multivariate model irrigation intensity, vegetative factors and poverty levels are strong predictors of guild richness (Whole model R2=0.521, P<0.0009). In arid urban areas, irrigation is a key driver of bird communities. Many communities like Fresno, CA are undergoing changes in water policies that are likely to change residents� irrigation behavior. Thus, understanding water management is critical for a deeper theoretical understanding of urban ecosystems and for effective urban policy.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Bourlard, Geraldine
- Description:
- Beattie and Setlow (1970) presented data to expand and confirm the "lethality mechanism" theory. Steinhart and Herriott (1968b) noted that their theory need not necessarily replace Schaeffer's "limited pairing" hypothesis since the integration level in their heterospecific transformation studies was only 48 to 78$, not 100$, of the homospecific level. Schaeffer (1958) had postulated that low transformation results may be due to the lack of structural identity between donor and recipient DNA, resulting in imperfect pairing. The present project was an attempt to determine whether sufficient chromosomal similarity exists to warrant the present taxonomic status of H. aphrophilus as a member of the genus Haemophilus.
- Resource Type:
- Thesis
- Identifier:
- ocm57407809
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Nelson, Rachel Lee
- Description:
- American Crows are common across the United States, well adapted to human habitats, and congregate in large winter roosts. We aimed to characterize the bacterial community (microbiota) of the crows’ feces, with an emphasis on human pathogens. The antibiotic resistance (AR) of the bacteria was analyzed to gain insight into the role crows may play in the spread of AR genes. Through 16S rRNA gene and metagenomic sequencing, the microbiota and antibiotic resistance genes (resistome) were determined. The core microbiota (taxa found in all crows) contained Lactobacillales (22.2% relative abundance), Enterobacteriales (21.9%) and Pseudomonadales (13.2%). Among the microbiota were human pathogens including Legionella, Camplycobacter, Staphylococcus, Streptococcus, and Treponema, among others. The Fresno, California crows displayed antibiotic resistance genes for multiple drug efflux pumps, macrolide-lincosamidestreptogramin
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Moore, Brett Tyler
- Description:
- Anthropogenic land use transformations impact watershed hydrology and increase fine sediment delivery to stream systems. These impacts are known to alter lotic macroinvertebrate assemblages, however much less is known about the mechanisms causing these changes. Fine sediment composition was investigated as a causal factor influencing macroinvertebrate distribution in the upper Fresno River watershed. Fine sediment composition was characterized as the total amount (mg/cm2), size distribution, and organic matter content of particles from 1.5 to 250 microns in the upper streambed substrate. Macroinvertebrate assemblages differed among 7 sites spaced throughout 169 stream kilometers. Six quantitative substrate variables: Dmean, Pareto c, specific surface area, sediment dry weight, % FPOM, and pebble count were used to construct fine sediment specific tolerance values for 21 common macroinvertebrate genera, identifying taxa that may be sensitive to development in the watershed. Sampling sites were scored using macroinvertebrate tolerance values based on water quality from literature and newly generated fine sediment tolerance values from the results. Fine sediment composition scores distinguished sites considerably more than water quality scores providing evidence that fine sediment composition was more important than water quality for assessing the biological difference between sites. Results demonstrate further links between fine sediment composition and macroinvertebrate assemblages and suggest a mechanism for how watershed development may change measures of ecological integrity.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Waters, Rosemary R.
- Description:
- It has been demonstrated in this laboratory that different strains of Staphylococcus aureus vary in their capacity to form L-phase organisms. Previous research by this writer produced data that indicated a strain of Staphylococcus aureus isolated from a throat culture of a student in a microbiology class at Fresno State College did predictably form L-phase organisms. This strain has been designated Staphylococcus aureus 219. This same research established optimal conditions for induction of L-forms from Staphylococcus aureus 219 with respect to culture age, agar concentration and penicillin concentration. It was also demonstrated that L-forms of this strain reverted to parent bacteria if the inducing agent was removed on the first to fourth transfer. However, by the fifth transfer typical L-form colonies were produced in the absence of the inducing agent. The purpose of this investigation was to further characterize environmental conditions necessary for induction of L-forms from Staphylococcus aureus 219, and to compare some morphological and physiological parameters of the parent bacteria, its L-form and its reverted L-form.
- Resource Type:
- Thesis
- Identifier:
- ocm64197532
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Krisch, Amy Lynn
- Description:
- The San Joaquin River Restoration Program (SJRRP) is preparing to reintroduce threatened spring-run Chinook salmon (Oncorhynchus tshawytscha) into the San Joaquin River between Friant Dam near Fresno, California and the confluence of the Merced River. To assess river conditions, the SJRRP collected physical habitat and benthic macroinvertebrate data in 2010, 2011, and 2012 using the Surface Water Ambient Monitoring Program s Standard Operating Procedures for Collecting Benthic Macroinvertebrate Samples and Associated Physical and Chemical Data for Ambient Bioassessments in California. Preliminary analysis of the benthic macroinvertebrate results revealed that the San Joaquin River is in good biological condition only between Friant Dam and Gravelly Ford. I used this segment as a reference site and compared the habitat and benthic macroinvertebrate abundance and diversity to the other segments, and answered where restoration should occur and which habitat variables need to be restored for sustaining salmon. I used analysis of variance (ANOVA), Fisher s Least Significant Difference (LSD), and principal component analysis (PCA) to show that the San Joaquin River between Gravelly Ford and Mendota Dam and the Eastside Bypass and Merced River are in need of restoration. Restoration should focus on riparian vegetation complexity, percent gravel, and instream habitat complexity by adding boulders, woody debris, and artificial structures.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Gonzales, Vanessa Alexandra
- Description:
- The Chinese mitten crab, Eriocheir sinensis, has a history of invasions in numerous countries. In 1992, the Chinese mitten crab was introduced to the San Francisco Bay/Delta system. Since its invasion in the San Francisco Bay, it has become an aquatic nuisance species. Little is known about the population dynamics of the megalopa stage of the Chinese mitten crab in the San Francisco Bay estuary, particularly the megalopa stage. Light traps are often used to sample marine larvae and can provide measures for relative abundance of larvae between sampling locations. As part of an ongoing study to monitor mitten crab larvae in the San Francisco Bay, light trap and plankton tow samples were analyzed for mitten crab megalopae and zoeae. In order to implement low cost sampling devices for mitten crab megalopae such as light traps, it is necessary to be able to identify their larvae in collected samples. Thus, the main objective of this work was to develop a means to distinguish mitten crab megalopae from other native and invasive brachyuran megalopae inhabiting the San Francisco Bay Estuary. The minimal amount of mitten crab megalopae found in light trap samples may be linked to the recent decline of mitten crab zoeae in San Pablo Bay.
- Resource Type:
- Thesis
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Robinson, Richard H
- Description:
- This brief paper is the first attempt to present a study of the habits and status of the wood duck, Aix, for the San Joaquin Valley of California. In a natural history survey involving a migratory bird such as this, two year' s observations cannot hope to produce a clear and precise picture, nevertheless it is hoped that some of the material presented will be of value to future investigators.
- Resource Type:
- Thesis
- Identifier:
- ocm62057785
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Grilione, Patricia L
- Description:
- The phenomenon of bacterial lysis by viral action was first reported by Twort (1915) and shortly after, D'Herelle (1926) described the concept of bacteriophagy. Contemporary writers tended to regard the two reports of lysis as due to the same phenomenon. This practice met with disapproval by D'Herelle who felt that Twort's failure to report "complete lysis or dissolution" of the bacterium set the letter's observations apart from "true bacteriophagy" as described by D'Herelle (1926).
- Resource Type:
- Thesis
- Identifier:
- ocm58536910
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Wilkinson, Arlene
- Description:
- This study is concerned with density of the bird population expressed as the actual number of non-breeding birds and the pairs of potential breeding birds living on thirty-tree and a third acres in the Foothills Woodland Community at the Experimental Range, Madera County, during the winter and spring of 1953. Generally a study of the density of the bird population is usually concerned with one or the other types of investigation, but since the writer kept records during the non-breeding and breeding season both results are included in this paper.
- Resource Type:
- Thesis
- Identifier:
- ocm63682898
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Takhar, Ajmel S
- Description:
- Raynier, (1792) suggested a direct internal visualization of the healthy stomach with food in it for the most exact physiological understanding. Beaumont (1883) observed the reddening of the gastric mucosa during emotional upsets in his subject, Alexis St. Martin, who had a traumatic gastric fistula caused by a gunshot wound. Cannon (1929) postulated that the emotions of fear and anger were inhibitory to gastric function. Wolff (1947) showed hyperemia of gastric mucosa with increased acidity during aggressive emotional states and pallor and flatness of mucosa with diminished acidity during the emotions of fear and sadness. Brady (1964) showed hypersecretion in his "executive" monkeys during post-avoidance conditioning and hyposecretion in pre-avoidance conditioning. Prout (1824) identified the acid of gastric juice as hydrochloric acid. Pavlov (1902) revolutionized the field of gastric physiology by making surgical pouches and isolating psychological vs. physiological phases of gastric secretion. Even today the study of acid secretion and its regulating components represents one of the most active areas of gastrointestinal investigation. Such terms as "acid stomach" and "heartburn" have become commonplace observations with regards to the production of too much or too little acid by the stomach.
- Resource Type:
- Thesis
- Identifier:
- ocm62862883
- Campus Tesim:
- Fresno
- Department:
- Biology
- Creator:
- Roque, Francis E
- Description:
- The adventitious roots of Poa annua and Poa pratensis are described both externally and internally. The roots of the two species differ in the size, length, position, and amount of xylem. The adventitous roots of Poa annua resemble the lateral roots of Poa pratensis, with the exception of the central duct which is made by the breakdown of the walls between two contiguous late metaxylem vessels in P. pratensis and P. annua, it is a single late metaxylem vessel. The adventitious roots of Poa annua produce more root hairs than do the laterals or sub-laterals, but Poa prantensis the lateral roots give rise to branches, but the sub-laterals apparently never branch. Poa prantensis exhibits two to four times as much branching as does Poa annua.
- Resource Type:
- Thesis
- Identifier:
- ocm62058604
- Campus Tesim:
- Fresno
- Department:
- Biology