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- Creator:
- Wahab, Allison
- Description:
- Current types of measurements such as employee surveys aim to measure employee satisfaction which aids in measuring leadership teams. Other measurements include leader evaluations which measures an individual’s performance. However, leader evaluations tend to focus on items that are easily measurable items such as budget, guest service scores, sells goals, etc. Leader evaluations do not tend to focus on items that are harder to quantify such as an individual leader’s contribution to the internal quality of the workplace. This is an issue because the workplace environment is a critical aspect to driving employee satisfaction which drives production quality and leaders play an enormous role in contributing to the internal quality of an organization. This study intended to aid in the creation of a measurement that can be used by any member, at any level of the organization to evaluate a leader’s effectiveness of their contribution to a positive work place environment. This study focuses on the well-being theory, creativity, communication, and commitment as drivers that contribute to a positive workplace environment. The development of measurable items is to be used on an individual basis. This allows for discoverable of opportunities in which an individual leader can improve their contribution to the betterment of the workplace environment.
- Resource Type:
- Graduate project
- Campus Tesim:
- Pomona
- Department:
- Collins College of Hospitality Management
- Creator:
- Tronske, Nicole
- Description:
- Rockweeds (Phaeophyceae, Fucales) are brown seaweeds that dominate temperate rocky intertidal and shallow subtidal habitats. These autogenic ecosystem engineers facilitate high diversity through provision of a canopy that ameliorates desiccation and thermal stress during emersion. In many parts of the world, however, rockweeds are declining. Given their declines and ecological importance, combined with low dispersal distances that limit recovery, rockweeds are strong candidates for restoration efforts. However, more research needs to be conducted to elucidate best restoration approaches and whether re-introduction or population enhancement of canopy-forming seaweeds results in cascading community changes. In southern California, the rockweed, Silvetia compressa has declined at numerous sites along the coast. Experimental transplantation of Silvetia has been conducted previously but the effects of restoration on subcanopy community composition and recruitment and the impact of transplant density was not examined. Consideration of transplant density may be particularly important as Silvetia naturally creates high-density beds with overlapping canopies, likely facilitating self-recruitment and a diverse understory community. Therefore, the goal of my study was to examine the effects of transplant density on: a) outplant survival and growth, b) recruitment of Silvetia, c) recruitment of other algae and invertebrates, and d) understory composition. Adult Silvetia were taken from a nearby, abundant donor population and transplanted in three density treatments (1, 2, and 4 transplants in 0.09 m2 plots); controls with no outplants were used for comparison. A year following transplantation, survivorship of outplants was lower than natural populations at the donor site, mostly driven by early mortality likely due to transplant shock. Transplant density did not affect either survival or growth of outplants but there was an effect on recruitment of some taxa. Generally, recruitment of Silvetia, mussels, and red algae was enhanced in high-density treatments while barnacle recruitment was inhibited by canopy presence, with the highest recruitment in control plots. The subcanopy assemblage changed quickly after a canopy was introduced, as compared to the control plots with no outplants, but did not differ among outplant density treatments. Generally, the presence of a canopy increased the abundance of perennial algae and reduced the amount of bare space. My study provides support that restoration of Silvetia, and likely other rockweeds, can be successful via transplanting, that canopy provision can alter subcanopy communities, and that higher outplant density increased self-recruitment, vital for a persistent and growing population following restoration efforts.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Pomona
- Department:
- Biological Sciences
- Creator:
- Trejo, Daniel Jay
- Description:
- Computational fluid dynamic simulations are performed at a systems level on a portable waste incinerator with actively forced, reacting jets through porous media. In total there are six jets with separate streams of fuel and oxidizer entering a porous region to induce a more profound mixing and reaction of the streams. The array of jets is intended to mimic industrial grade burners wherein regions of porous material are used in the manufacturing of the combustion device. Simulations are performed with the commercially available software, ANSYS-FLUENT. The jets are modeled as non-premixed, methane-air global undergoing one step reaction kinetics with interaction in porous media regions. The primary objective of the study is to ascertain the amount of heat release and the heat transfer characteristics of the overall system of jets and combustion chamber. The addition of porous media is to suppress the maximum flame temperature and to distribute the flame structure in a more controlled manner.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Pomona
- Department:
- Mechanical Engineering
- Creator:
- Tai, Emily
- Description:
- In recent years, Major Depressive Disorder (MDD) has been documented with both higher rates of incidence and earlier age of onset. Though treatments for MDD currently exist, they are limited by inherent obstacles, such as anergia and decreased motivation, or by external obstacles such as lack of knowledge or social stigma. Complications such as these could potentially be improved upon through dietary intervention, with dietary changes allowing for a mitigation of depressive symptoms that can compliment traditional antidepressant treatment. Chia, as a food product high in omega-3 fatty acids, tryptophan, and antioxidants, could be beneficial for the management of MDD. In addition, because chia can be easily incorporated into different foods, it can be easily introduced to the diets of individuals who suffer decreased motivation or energy due to depression. To study the potential effects, participants from the California State Polytechnic University, Pomona campus were recruited for an 8-week study period, taking either water or chia mixed with water 30 minutes prior to each meal. Depressive symptoms, sleep quality, and urinary serotonin were measured through the Major Depression Inventory, the Pittsburg Sleep Quality Index, and urinary serotonin ELISA results taken before, during, and after the treatment period. Though chia supplementation was not confirmed to reduce depressive symptoms, improve sleep quality, or increase urinary serotonin in this study, further examination into alternative methods of processing chia could still prove beneficial.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Pomona
- Department:
- Nutrition & Food Science
- Creator:
- Sutkowski, Chloe
- Description:
- In the mid-1800s, La Placita de Los Trujillos (La Placita) was situated alongside the Santa Ana River (SAR) in what is now Colton, CA. The settlement had grown to be the largest non-native community between New Mexico and Los Angeles, until the river washed away or buried all adobe structures and settlers’ belongings during the Great Flood of 1862. Historical archives reveal that a significant portion of San Salvador is buried approximately 3 meters beneath sandy flood deposits of the vacant, 200-acre lot of Pellissier Ranch. The motivation for this study was to provide the Spanish Town Heritage Foundation with data they could use to advocate the cultural importance of Pellissier Ranch in their attempt to stop the city from developing the site for warehouses. From April 2018 to January 2020, we conducted eleven days of geophysical field surveys in search of buried adobe structural remains, household items composed of wood and iron, and large farming equipment that would have existed in La Placita. Over 7,000 meters of ground-penetrating radar (GPR) profiles were acquired with both a GSSI-SIR 3000 and 4000, using the 400 MHz and 350 MHz HyperStacking antennas respectively, and 25 km of magnetic gradiometry data was acquired using a GEM GSM-19T Proton Precession Magnetic Gradiometer. GPR profiles imaged several 'adobe melt' signatures at a depth range of 1.4 - 3.8 meters, and two buried canals with surfaces reaching 1.3 meters below the surface, and bottom depths of 2.5 meters. Additional structural GPR anomalies vary in size from 9 - 70 meters at a depths of 1 - 3.8 meters. We hypothesize that some of the shallower buried (sub-2-meters) anomalies exist for a few reasons: the portion of the anomalous feature closer to the river absorbed the majority of the river's force, which shielded the more intact part, or the location did not experience the full strength of the river's force, causing less destruction and burial beneath the sandy flood deposits. Contemporary debris from trespassers resulted in many false-positives in gradiometer results that needed to be excluded from mapped vertical gradients. We therefore focused more heavily on GPR results, using the gradiometer as a complementary technique to attempt to verify anomalies we imaged with GPR. In two locations, we observed a positive correlation between the two data-sets, attributed to a sub-2-meter burial of anomalies. This confirms claims made by other researchers that features / artifacts with low magnetic content cannot be seen if buried deeper than 2 meters. From our results, we conclude with confidence that several anomalies we imaged in GPR profiles can be related to structures / features of La Placita, and the depth range of the settlement at Pellissier Ranch is primarily 2 - 3.8 meters. Based on our surveys, we suggest to focus any future investigation in the middle of Pellissier Ranch. There is one east-west dirt road that cuts through the middle of the 200-acre site. At about the halfway point of that east-west road, we found a collection of promising anomalies.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Pomona
- Department:
- Geological Sciences
- Creator:
- Sarmiento, Desiree Joyce
- Description:
- A group of polyphenols called flavonoids, which are abundant in a variety of fruits, vegetables, and medicinal plants, have gained increasing interest due to their antioxidant properties. Flavonoids are rich in fruit juices, of which orange juice has a largescale production. However, this juicing process produces tons of waste each year in the form of orange pomace, in which flavonoids are still present in a large amount. In this project, the major citrus flavonoids, naringin and hesperidin, were extracted from dry orange pomace samples of Ctirus sinensis over pure ethanol using the Soxhlet technique and analyzed by high performance liquid chromatography coupled with diode array detection. Experimental results showed that 63.2 mg hesperidin/g dry mass is present in Citrus sinensis pomace while naringin was not found in Citrus sinensis. Additionally, limonin which is largely known for its delayed bitterness effect in citrus was also identified on the chromatogram and was below the quantifiable limit of the method. Additional peaks were also observed on the chromatogram, which will require further research of these unidentified analytes. Moreover, orange pomace extract exhibited antioxidant behavior, demonstrated by the increased percent (%) inhibition of DPPH when orange pomace extract was present. Quantitative assessment of OP’s antioxidant activity will be carried out in future work.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Pomona
- Department:
- Chemistry and Biochemistry
- Creator:
- Ongjoco, Anna Jiselle
- Description:
- Plants use an isohydric or an anisohydric strategy to cope with declining soil moisture availability and increasing evaporative demand. The goal of this study was to determine the physiological and structural strategies utilized by Pinus attenuata (knobcone pine) and Pinus coulteri (Coulter pine) at low elevations in the San Bernardino Mountains of California, which experienced above-average precipitation after a severe seven-year drought. Based on a previous study, it was hypothesized that P. attenuata should be isohydric and P. coulteri should be anisohydric because P. attenuata has a slower transpirational loss of water than P. coulteri. Physiological, morphological, and anatomical measurements were used to compare the responses of the two species to seasonal environmental changes and induced drought. In the field, P. coulteri had greater water potentials and maximum quantum yields of photosystem II than did P. attenuata; however, gas exchange did not differ with species. In a controlled drought study, young P. coulteri had higher water potentials and gas exchange than young P. attenuata, with P. coulteri continuing to take up CO2 two weeks after P. attenuata had ceased uptake; however, P. attenuata took up CO2 at lower water potentials than P. coulteri. Tracheid diameter was larger for P. coulteri than P. attenuata for bands of late wood only and tracheid cell wall thickness did not differ with species. The species did not differ in plant height, but P. attenuata at low elevations had the smallest diameter at breast height, indicating P. coulteri could transport and store more water where it occurred. Finally, neither species experienced extensive branch or canopy dieback due to the previous drought. In conclusion, based on their physiological responses, both species appear to be isohydric, but also display some traits of anisohydric species.
- Resource Type:
- Masters Thesis
- Campus Tesim:
- Pomona
- Department:
- Biological Sciences
- Creator:
- Muro, Sandra
- Description:
- Juliidae E.A. Smith, 1885 is a family of Sacoglossan bivalve gastropods mistakenly placed in Bivalvia when initially discovered. These are the only known gastropods with bivalve shells, making them a morphologically unique group. A recent morphological and molecular study for the entire family Juliidae incorporated 21 samples of Julia (J. exquisita, J. zebra, and J. sp.) from six general localities worldwide and found support for unrecognized species diversity within the genus (three candidate species). Julia species were also previously reported to have interesting disjunct geographic distributions across the Indo-Pacific, often with overlapping ranges. These preliminary molecular results, in addition to their widespread distributions, warranted further investigation into Julia, especially since other recent studies on heterobranch sea slugs have revealed cryptic and pseudocryptic species in groups with large distributions. The objectives of this study were to use molecular sequence data to identify and delineate species of Julia using a more comprehensive representation of individuals across their ranges and supplement these data with morphological analyses of the bivalve shells to aid in potential species descriptions. The majority of the molecular data for this study were obtained from historical collections from several natural history museums, using DNA extraction methods that allowed the use of these dried, unpreserved specimens that were previously thought to yield insufficient or no DNA. One nuclear (H3) and two mitochondrial genes (CO1 and 16S) were used to establish a Bayesian and Maximum Likelihood phylogenetic hypothesis for members of Julia. Haplotype networks using the CO1 gene were created to visualize geographic differentiation. An Automatic Barcode Gap Discovery (ABGD) analysis recovered a total of 20 candidate species that coincide with monophyletic clades on the phylogenetic trees. Candidate species of Julia were found to be sympatric and haplotype networks showed little geographic differentiation among disjunct individuals within the same species. Morphological characteristics were found to be different among species complexes, however more data are needed to make conclusions about defining characteristics for candidate species recovered with genetic data. This study not only highlights the importance of museum collections in documenting species diversity, but also provides a framework for studying the evolution and biogeographical patterns of a group whose taxonomy, ecology, and overall biology have proven to be obscure since its initial discovery. This study provides an updated taxonomy of a morphologically interesting group that can help in future research of biogeographic and speciation patterns in other groups of organisms that share similar diversity and distributions.
- Resource Type:
- Graduate project
- Campus Tesim:
- Pomona
- Department:
- Biological Sciences
- Creator:
- Moreno, Karina
- Description:
- The genus Cyerce Bergh 1871 is a group of heterobranch sea slugs in the family Caliphyllidae, characterized as having bifid rhinophores, enrolled oral tentacles, multiple leaf-like cerata, and a transverse groove splitting the foot sole of the animal transversally. Cyerce currently includes eight to eleven accepted species distributed throughout tropical and subtropical areas of the Indo-West Pacific, Eastern Pacific, Northern Atlantic, Caribbean, and Mediterranean. Species of Cyerce are stenotropic herbivores that possess remarkable adaptations, such as aposematic coloration, synthesis of polypropionates, and acquisition of plastids from their algal hosts. The evolution of these traits in Cyerce has not been studied, although observed in other lineages within Sacoglossa. Cladistic analyses have been performed on Sacoglossa, but species level phylogenetic analyses for the genus Cyerce are lacking. Morphological studies have been used to distinguish species of Cyerce in past studies, but the evolutionary relationships among these species remain undetermined. The objective of this study is to produce a monographic review of the genus Cyerce using both molecular and morphological data. In order to resolve the evolutionary relationships among Cyerce species, two mitochondrial genes (CO1, 16S) and a nuclear gene (H3) were sequenced from one hundred and fifty-four specimens loaned from museums or collected in the field. Bayesian and Maximum Likelihood analysis were used to generate phylogenetic trees. A species delimitation analysis with ABGD was performed using CO1 aligned sequences to delineate species among the clades recovered in the phylogenetic analyses. The internal anatomy of the Cyerce specimens was studied to supplement molecular data. This included dissections of the radula and male reproductive anatomy. A literature review was further conducted to investigate the validity of species. Twenty-four genetically distinct species of Cyerce were recovered from the analyses with diagnostic in differences penial and radular morphology between species. This study also resulted in novel findings, such as evidence of fifteen new species of Cyerce. From the fifteen new species, several belong to cryptic and pseudocryptic species complexes that, without the integration of molecular and morphological data, would not have been discovered.
- Resource Type:
- Graduate project
- Campus Tesim:
- Pomona
- Department:
- Biological Sciences
- Creator:
- Macy, Kyle
- Description:
- The Yorba Linda Trend is a proposed NE-SW alignment of earthquakes near the western edge of the Los Angeles Basin in southern California first described by Egill Hauksson in the early 1990s (Hauksson, 1990). Most earthquakes in this area exhibit a strike-slip mechanism, but they do not fall on or near any mapped fault traces. More recent events and earthquake sequences have occurred within the boundaries of the Yorba Linda Trend since its conception: the 2002 Yorba Linda and 2008 Chino Hills earthquakes. These two sequences may now be considered part of this trend. Both of these sequences have a northeast-southwest striking orientation. The 2014 La Habra earthquake sequence located nearby follows a parallel orientation. The largest events of each of these sequences all exhibit a strike slip or oblique mechanism. The aftershock sequences, combined with the mechanisms, suggest previously unmapped left-lateral strike-slip faults may be responsible, but their exact geometry is unclear. Bookshelf faulting within the Chino Hills, potentially produced by the tectonic movement of the Whittier Fault and the Chino Fault may provide an explanation to the origin of some of these earthquakes. Because a majority of these earthquakes are small, they are poorly located. Seismic relocation using waveform cross-correlation allows for these small events to be relocated with a relatively high accuracy and for possible fault structures to be revealed. In this study, we utilized the GISMO cross correlation MATLAB toolbox (Thompson & Reyes, 2018) to determine correlation values and lag times of similar earthquakes in order to improve the arrival time measurements of the P- and S-waves of these earthquakes. We then entered these improved arrival times in the GrowClust relative relocation algorithm (Trugman & Shearer, 2017). In this relocation procedure, we used three 1-D velocity models: the IASP91 velocity model (Kennett & Engdahl, 1991), the smoothed southern California velocity model (Shao et al., 2012), and the Los Angeles Basin velocity model determined from the 1987 Whittier Narrows Earthquake (Hauksson et al., 2008) under a 0.2 sec RMS differential travel time residual, as well as a 0.6 sec differential travel time residual to successfully relocate earthquakes in the region of the YLT from 1989 to 2018. Each of the results for the six relocation attempts reveals two distinct clusters of earthquakes that are relatively planar centered around the 2008 Chino Hills Earthquake and the 2002 Yorba Linda Earthquakes. A noticeable gap is present between these two sequences. Relocation of the 2014 La Habra Sequence has aligned these earthquakes to form a northwest dipping planar structure, with many events clustered around the Coyote Hills Fault System. Other clusters of seismicity that were revealed by the GrowClust relocation show a system of earthquakes within the Los Angeles Basin just north of the Peralta Hills and El Modeno Faults, which may be anthropogenically induced by oil extraction within the Richfield Oil Field. None of the relocation results show a clear through-going planar structure connecting the Yorba Linda and Chino Hills Sequences. In addition, we do not see any seismicity trends that imply the presence of bookshelf faulting that connect the two sequences. The Yorba Linda Sequence may be situated along a high angle fault structure to the Whittier Fault. The orientation of this fault structure in combination with the focal mechanisms is indicative of a left-lateral strike slip fault. The Chino Hills Sequence is situated along a similarly oriented fault. Relocations of the La Habra Sequence consistently reveal that these events are oriented along a northeast-southwest striking fault, beginning at the Whittier Fault and extending towards the Coyote Hills Fault System. This orientation, in combination with the focal mechanisms of this sequence, would imply the existence of a steeply dipping or near vertical left-lateral strike-slip fault.
- Resource Type:
- Graduate project
- Campus Tesim:
- Pomona
- Department:
- Geological Sciences
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