Spermatogenesis pauses only at the penultimate stage, the spermatid. The pause ends when an external signal activates the spermatid into a spermatozoon. Activation involves two pathways: (i) the try-5 pathway, named because the trypsin-like protein TR . . .

During the aquatic nymphal stage, dragonflies possess a modified labium that functions as a high-speed raptorial appendage used in prey capture. During labial protraction, a preparatory phase of slow protraction is followed by the release of a latched . . .

Across species, males and females have been shown to have marked differences in their immune responses and resistance to various microbial infections. Sex-based differences, such as the X and Y chromosomes and sex hormones are, in part, believed to be . . .

Ice is defined as a food and is frequently used in direct contact with food and beverages. Packaged ice is commercially produced and can be easily found in grocery and convenience stores. However, the quality and safety of packaged ice products is not . . .

Many biological processes are driven by endogenous 24-hour cycles known as circadian rhythms. Recent studies implicate dopamine signaling as a key mediator of entraining circadian activity cycles to feeding. To measure the influence of food on circadi . . .

Human adipogenesis is the process through which uncommitted human mesenchymal stem cells (hMSCs) differentiate into adipocytes (fat cells). Understanding the molecular and cellular regulation of human adipogenesis may provide a way to prevent and/or t . . .

Listeria monocytogenes is a pathogenic bacterium that causes the foodborne illness listeriosis, which is estimated to infect 23,000 and kill 5,000 globally each year. L. monocytogenes is a particularly problematic pathogen due to both the lethality of . . .

The fungus Aspergillus can cause a serious pulmonary infection (aspergillosis) in immunocompromised patients, with 80% mortality if untreated. Aspergillosis also affects the poultry industry as chickens and turkeys are highly susceptible, leading to m . . .

Rocky intertidal habitats in urbanized settings, such as in southern California, are heavily perturbed by human visitors through the deleterious activities of trampling, handling, and collecting. To protect rocky intertidal biota, certain locations ha . . .

Dopamine is a neurotransmitter highly associated with reward. The Dopamine Transporter (DAT, Slc6a3) is a transmembrane protein responsible for reuptake of dopamine at the synaptic cleft. This transporter is vital for the termination of dopamine signa . . .

The North Pacific nudibranch species Triopha catalinae (Cooper, 1863), also known as the clown nudibranch, includes two distinct morphotypes based on photographic records, the northern morphotype found from South Korea to Central California, and the s . . .

Rocky intertidal ecosystems are harsh habitats subject to numerous disturbances that can influence community composition based on the recovery dynamics of impacted species. The middle intertidal zone of temperate rocky shores, such as in southern Cali . . .

Ecomorphological studies of lizards have revealed relationships between cranial musculoskeletal morphology and dietary ecology, as well as patterns of sexual dimorphism related to social behavior. Such patterns previously have been described in crotap . . .

Thigmomorphogensis is the response by plants to mechanical stress during growth and development. For trees, wind stress can result in stunted height, shortened and wider branches, increased fiber abundance, and more reaction wood. It was hypothesized . . .

Island and coastal species are typically exposed to more fog but less rain than mainland species. Because adaptations to absorb water from fog or mist may be in conflict with those to minimize water loss, I hypothesized that due to natural selection i . . .

Environmental heterogeneity of resources is thought to have important functions in the mechanisms that influence species coexistence. This thesis research explores how environmental heterogeneity created by canopy trees may influence coexistence of an . . .

Circulating blood monocytes are naive cells that differentiate into macrophages. Macrophages (along with Natural Killer (NK) cells, mast cells, and granulocyte derived cells) are an essential part of the innate immune system. Macrophages phagocytize m . . .

Botulism is a fatal disease caused by the botulinum neurotoxin (BoNT), a lethal exotoxin affecting the peripheral nervous system leading to descending flaccid paralysis and respiratory failure. BoNT exists as part of a progenitor toxin complex (PTC) a . . .

Viruses are curious biological entities that are parasites of their respective host cells. Archaeal viruses have been found to share many characteristics with eukaryotic and bacterial viruses; however, our understanding of archaeal viruses is comparat . . .

Worldwide 417 million people ages 15-49 years old have Herpes Simplex Virus type 2 (HSV-2) genital infection. HSV-2 establishes latent infections in sensory neurons of the dorsal root ganglion, with periodic reactivation that results in a lifetime of . . .

Trichomonas vaginalis (Tv) is a parasite that causes the most common non-viral sexually transmitted infection worldwide, and annually infects 3.7 million people in the United States. Tv is associated with fertility and pregnancy issues, such as infert . . .

Many biological processes are driven by endogenous 24-hour cycles known as circadian rhythms. Recent studies implicate dopamine signaling as a key mediator of entraining circadian and ultradian rhythms, particularly of activity. The system behind ligh . . .

It is a biological constant that viruses are found associated with all known life and that they play an essential role in the ecology and evolution of all life-forms. Compared to viruses that infect Eukarya and Bacteria, little is known about the viru . . .

In marine ecosystems, herbivory can play a vital role in structuring community composition and maintaining normal ecosystem functioning. Found in southern California intertidal and subtidal habitats, the Black Sea Hare Aplysia vaccaria, has been descr . . .

With the increase in immunocompromised patients due to new life-saving procedures such as liver and stem cell transplants, invasive candidiasis, caused by opportunistic pathogens, such as Candida spp., is a major health problem with high morbidity and . . .

Juglone (5-hydroxy-1,4-naphthoquinone) is the allelopathic compound produced by plants in the family Juglandaceae, which includes pecans, hickory, and walnuts. Throughout history, walnuts were observed to decrease the growth and fitness of neighboring . . .

Allelopathy is the chemical inhibition of one plant by another. Southern California black walnut (Juglans californica) occurs in a pure walnut woodland at the Lyle Center for Regenerative Studies on the campus of Cal Poly Pomona and produces the allel . . .

Human prosthetics are being utilized more frequently as the populations that require their use expand. These cohorts include elderly population, injured war veterans, and general public who suffer from serious accidental injury. Solid biomaterials wit . . .

The molecular basis of spider silk production is of interest partially because it may lead to innovations in material science. Dragline silk, which is produced in the major ampullate gland of spiders, has been found to be tougher than nylon and Kevlar . . .

Interest in wild or native bees residing in urban/suburban areas has increased with much publicized declines in wild bee diversity and abundance. Many homeowners in the Los Angeles region use more native plants in their gardens to have more water effi . . .

Polycomb group (PcG) proteins are epigenetic modifiers participating in the regulation of gene expression and are indispensable for the development of multicellular organisms. They selectively repress gene expression via the formation of multi-subunit . . .

BACKGROUND: 10-15% of nosocomial urinary tract infections are caused by Candida spp. in individuals with indwelling catheters, especially those in the ICU or residents in assisted living settings. These infections are increasingly being caused by orga . . .

Trichomonas vaginalis (T. vaginalis) causes the non-viral sexually transmitted infection (STI), trichomoniasis. Trichomoniasis affected almost 276.4 million people globally in 2008 alone, with most incidents occurring in underserved communities. The m . . .

Juglans californica (California black walnut) is a threatened low-growing hardwood tree endemic to Southern California that sprouts shoots from belowground biomass when recovering from a fire. During the most extreme drought in recorded history, J. ca . . .

Breast cancer is the most common non-skin cancer among American women. Comparing with early stage breast cancer, Stage IV or metastatic breast cancer has much lower 5 year survival rate (22%) and is a major threat to women’s health. The metastatic pro . . .

The supply of seeds to a system, or propagule pressure, is a strong predictor of invasion success. As the propagule pressure of a non-native species increases, competition with native species may be overcome, promoting invasion as well as the extirpat . . .

Life-threatening pulmonary aspergillosis, caused by Aspergillus fumigatus, is most common in immunocompromised individuals and birds. Treatment with antifungal drugs is associated with only 50% survival, underscoring the need for an Aspergillus vaccin . . .

Taxonomic classification of sea slugs has long relied on morphological characteristics such as color and size when identifying species. With the increased access to DNA analysis, it is now possible to organize species based on a molecular level. The c . . .

Recent and significant environmental changes have greatly affected native plant recruitment and re-establishment in patchy Mediterranean plant communities. Prolonged drought, urban development, and invasion by non-native annual plants have created a m . . .

A structure within the hypothalamus, known as the suprachiasmatic nucleus (SCN), acts as a central clock for the body. It regulates biological rhythms that occur with a near 24-hour period, otherwise known as circadian rhythms. These rhythms, such as . . .

A recent study characterized the common and charismatic sea slug species Hermissenda crassicornis (Eschscholtz, 1831) as a species complex of three distinct species. Hermissenda crassicornis and H. opalescens (Cooper, 1831) are two pseudocryptic siste . . .

In the year 2010 the Deepwater Horizon (DWH) oil spill released approximately 700,000 m3 of crude oil into the Gulf of Mexico (Crone and Tolstoy, 2010). It is considered one of the biggest oil spills in history (Crone and Tolstoy, 2010). The DWH oil s . . .

California black walnut (Juglans californica S. Watson) is a threatened and endemic tree species that has been previously studied for its ability to resprout following the occurrence of a wildfire, in which fire resprouts displayed a hydraulic and pho . . .

∆9-tetrahydrocannabinol (Δ9-THC) is the primary psychoactive constituent of Marijuana. Δ9-THC is known to suppress mouse resistance to bacterial, viral, and protozoan infections, but the effects of Δ9-THC on fungal infections are unclear. Marijuana us . . .

Gender plays a major role in an organism’s immune response to many pathogens. However, little is known about gender’s effect on Candida albicans (C. albicans) infections. C. albicans is a commensal organism that lives in the mucosa and skin of healthy . . .

California sage scrub (CSS), an endangered ecosystem consisting of deciduous shrubs like California sagebrush (Artemisia californica), black sage (Salvia mellifera), white sage (Salvia apiana), and California buckwheat (Eriogonum fasciculatum), occupi . . .

Gamma-aminobutyric acid (GABA) is the predominant inhibitory neurotransmitter in the mammalian central nervous system. Regulation of synaptic and extra-synaptic GABA concentrations in the brain is carried out by four high-affinity GABA transporter (GA . . .

Introduction: Influenza virus can cause epidemic or pandemic infections due to the emergence of new viral strains to which the host has little or no previous immunity. The variation from strain to strain occurs because of the frequent mutations of the . . .

The Southern Alligator Lizard (Elgaria multicarinata) exhibits an unusual courtship behavior during which the male firmly grips the female’s head in his jaws for many hours at a time. This behavior counters the conventional wisdom that non-avian repti . . .

Rockweeds (Phaeophyceae, Fucales) can dominate rocky intertidal habitats in temperate ecosystems and are considered ecosystem engineers, supporting a diversity of flora and fauna that find refuge from desiccation stress underneath the rockweed canopy. . . .