Cultural backgrounds are foundations for the way we speak, interpret, and behave. This study examines cultural-related factors that influence the selection of extracurricular activities by African-American students and Asian students from China and Korea. These cultural factors are being examined along with their influence on the success rate (I.E., graduating with a competitive GPA) of these students. This is important because our society is becoming increasingly more culturally diverse and more competitive for students pursuing higher education. Understanding cultural differences will help determine why certain cultures do particular things. Looking at the cultural factors, as well as societal pressures geared toward high school students of color, it is interesting to present differences in activites that have been believed to be the students choices to participate in. The activities outside of school can negatively or positively affect a student's ability to succeed because the time outside of school will not be spent entirely on coursework. The methodology of this research is conducting literature review of current research in the areas of outside of school activities in relation to cultural influences and academic success. The anticipated results are that the socioeconomic status, education level, and geographic location of the high school student's parents influences the choices of extracurricular activities for the student. Activities that are intellectually stimulated or academia related are activities that positively affect a students' success while activities that do not use information learned in school negatively affect a students' success. The differences in the cultural factors raise questions as to why different activities are pursured by students of different cultural backgrounds. Knowing why there are differences will help schools determine where money needs to go or what measures need to be taken in order to encourage students to pursue activities that are not normally participated in.

The Brome Mosaic Virus (BMV) is an RNA virus that infects granary plants. It consists of three distinct viral particles which consists of each of three distinct BMV RNA molecules wrapped by many copies of the Coat Protein (CP). CP's regulatory roles in the replication processes of BMV are conducted through controlling the efficiency of both RNA replication and protein translation. Previous studies have shown that a 22-residue peptide (CPNT) derived from the N terminal region of CP can penetrate the host cell membrane and deliver the BMV genomic RNA into the host cell. The long-term goal of this project is to investigate the conformational characteristics of CPNT and to explore its binding characteristics on the different parts of BMV genomic RNA. As a first step, a 29 residue-long peptide mimicking the N-terminal region of CP (CPNT-1) was chemically synthesized and its overall conformation was investigated using Circular Dichroism (CD) and nuclear magnetic resonance (NMR). The CD spectra showed that it has only 12% of a-helix structure and 50% of random coil, implicating high conformational flexibility. Given that these Cys residues are not a part of the functionally crucial region of CPNT, we designed a new CPNT construct without any Cys residues (CPNT-2). Our preliminary results showed that the 1 dimensional NMR spectra showed that CPNT forms appreciable amount of secondary and/or tertiary structures in native sequence (27 amino acid residues on N’ end: CPNT-2). When the end of CPNT was replaced by multiple Cys residues (CPNT-1), it is either aggregated or becomes a random, flexible conformation. CD as well as nuclear magnetic resonance analyses have been performed on CPNT-2 and the preliminary data showed that the peptide forms secondary structure. Currently we are investigating the detailed structural characteristics of CPNT-2 using CD and nuclear magnetic resonance analysis.

The process of a sperm entering an egg during fertilization is not well-understood at the molecular level for any organism. Drosophila melanogaster, the fruit fly, serves as an ideal model organism to study the normal process of fertilization and what goes awry in cases of sterility. A novel membrane protein termed GCS1 is suggested to play a crucial role in fertilization in angiosperm plants and protists. Disruptions of the gene in these organisms are sterile due to defects in gamete interactions. Comparative genomics suggest that GCS1-like proteins are conserved across a wide variety of eukaryotic species, including Drosophila, suggesting that the GCS1 gene is of ancient origin. We have cloned a genomic fragment containing a putative Drosophila GCS1-like homologue (dGCS1) and showed that it rescues mutations in a gene called pskl, which when mutated results in male sterility. This result confirms that dGCS1, like GCS1 in other organisms, plays a role in fertilization. However, our mutants also show that dGCS1 has roles in both sperm formation and sperm function during fertilization. Currently, we are using Minos, a DNA transposon inserted near a protein-coding exon of the dGCS1, to disrupt the gene. We have obtained over 100 Minos excision alleles and are comparing these derivatives genetically and molecularly to determine if we can define specific portions of the dGCS1 protein that contribute to male fertility. These ongoing studies should be informative for identifying regions of the Drosophila gene and protein that are important for function, and should shed light on how GCS1s in general function during fertilization.

Mesanchymal stem cells (MSC) can differentiate into a variety of cell lineages, including adipocytes, chondrocytes, and osteoblasts. This gives them great potential for use in regenerative medicine. To harness this potential, we must understand the effects of the various stimuli that can be applied to cells in in vitro culture. We produced an ECM mimetic nano-grooved cell culture substrate via capillary force lithography. An agarose diffusive microfluidic device was used to establish an SDF-1 α gradient across the nanogrooved substrate. Bone marrow derived mesanchymal stem cells (BM-MSC) were seeded on the substrate, and live cell imaging was carried out over a few days’ time. Using the time-lapse images, the differentiation, proliferation, motility, and elongation of the BM-MSC were analyzed and quantified. Understanding the synergistic effects of topography and bio molecular gradients will prove helpful in future efforts to create MSC regenerative medicines.

Relationships can be beneficial in many aspects of one’s life. For example, intimate relationships may provide individuals with the ability to cope in stressful circumstances. On the other hand, it may cause an individual to experience more stress during different situations. Bergman and Surrey (2009) found couples may experience as many as 3 or 4 stressful situations in a given day. According to previous research, couples faced with certain stressful situations will often look to their significant other for support (Neff, 2009). I will be looking at intimate romantic couples for this study. I will examine if couples help or hinder their partners during a stressful situation. By using math problems as a stressor, I will examine how couples cope with stress with their partner and if their significant other increases or decreases their stress during and after the process of solving a math problem. Having each one take the survey, I will be assessing the stress levels of both partners. In this study, I will use the Math Self-Concept Scale (MSCS), the Statistics Test Anxiety-Emotionality (STAE), Cooperative Problem-Solving Measure (CPSM), Subjective Units of Distress Level (SUDS), and math equations for the survey they will be taking. These measures will examine each individual’s level of stress before, during, and after the survey questions are completed.  I anticipate, during the process of solving math equations, the involvement of an individual’s partner will either increase or decrease their stress levels associated with the activity. I hypothesize that the individuals who are assisting their partners who are taking the survey will find themselves more stressed during the problem solving process and less stressed after the activity ends. This study could provide professionals and counselors with some valuable information that could perhaps teach couples more successful methods of support and communication.

In 1965, the Higher Education Act was signed by President Lyndon Johnson to provide financial assistance for need- based students in higher education. Under Title IV of the HEA, student financial aid programs and educational opportunity programs are administered, including the Federal TRIO Programs. TRIO has eight programs targeted to serve and assist low-income individuals, first-generation college students from disadvantaged backgrounds to progress academically from junior high school to post baccalaureate studies. One of the eight programs under TRIO is the Ronald E. McNair Post-Baccalaureate Achievement Program; designed to aid historically underrepresented undergraduates attain PhD degrees and assist students in academic and professional development. The purpose of the McNair Program is to prepare undergraduates for doctoral study through participation in research and scholarly activities. McNair Scholars have often faced hardships; whether financial, family, scholastic, or health; and have had critical experiences and relationships that have propelled them to continue with higher education. By interviewing McNair Scholars and engaging in literature review, this research will present an in-depth exploration of their behavioral patterns and find a theme to their academic success, such as social capital. The goal of this research is to reinforce the impact of educational programs that aid underrepresented students at an early stage to better prepare them for post-secondary school and doctoral studies. Also, by examining behavioral patterns possible solutions will be gained to implement towards higher education for underrepresented students.

Animals must strive for a balance between foraging for food and avoiding danger in their daily environments. The amygdala has been shown to be a key brain structure involved in mediating both innate and learned fear responses in order to optimize the organism’s survival. Previous research using Pavlovian fear conditioning has shown that animals without an amygdala have deficits associating a conditioned stimulus (CS) with an aversive unconditioned stimulus (US). A Closed Economy is a semi-naturalistic paradigm in which all nutritional needs are met by completing a cost of procurement. Male Long-Evans rats were housed in the Closed Economy chambers for 24 hours under aversive stimulation in the form of foot-shocks (US) preceded by a light CS in the foraging area. I investigated whether the amygdala’s role in the modulation of foraging strategies is affected by the predictability of fear. Electrolytic lesions to the basal lateral amygdala (BLA) and central amygdala (CeA) were given to the experimental group, while controls were given sham surgeries. The animals were shaped to a chained fixed ratio 50-continuous reinforcement schedule, by which they were able to control their meal frequency and average meal size. After stable meal patterns were obtained, the rats went through seven day periods of baseline, shock, and extinction. Animals with lesions to the BLA and CeA initially exhibited deficits in the light-shock pairing, but over time, learned to avoid the shock in the foraging area. These results question whether the amygdala is necessary in associative fear learning and suggests possible compensatory mechanisms that could mediate long term fear learning in an environment with a chronic exposure to an aversive stimulus.

In nearly all institutions, programs exist with the goal to recruit a diverse body of applicants and then, to retain this diverse body of students. Diversity is a loaded term, yet the federal definition – which I will be following – focuses on underrepresented, low-income and first generation students. This research project examines the specific steps involved in attaining a higher education and identifies factors, which enhanced their chances, and barriers, which they had to overcome. There is a lot of research done on the effectiveness of these programs, both K-12 pre-college and programs in the university. However, it is important to look at another aspect: the role the surrounding community plays in the pre-college experience, including preparation and motivation. I am conducting a literary review on the power that social and cultural capital holds in a students success at achieving a higher education. Through this research we can institute a new community based program that will effectively address these barriers, as well as enable us to address the current recruitment and retention programs in state to make them more effective.

Previous research has shown that the economic/income level of Hispanic families is associated to the type of treatments children and adolescents receive. However, little research has examined other possible predictors that affect the type of treatment approaches Hispanic children receive who are diagnosed with depression. It is important to look at possible factors in order to understand why some cases would end up in premature termination or why others have higher levels of success. It is believed that possible predictors of type of approaches to treatments are cultural aspects for immigrant families, ethnic match with their therapist, treatment acceptability and treatment barriers (transportations, babysitter, lack of understanding, etc.) This study hypothesized that Hispanic families would choose certain therapies as more favorable based on the accessibility and the ethnic background of their case manager and have the potential to lead to higher rates of success and decrease the rate of premature termination. The result of the study provides support for the current findings of favored therapeutic approaches by other ethnic communities and further construct a better-designed accessibility to treatments.

This research explores music education as a potential vehicle for enhancing socially desirable behaviours in young people and teaching inhibition of socially undesirable behaviours as well as increasing proficiency in language, math and science. There will be special focus on methods of teaching that are noncompetitive such as Suzuki’s Talent Education Method. It involves literary review synthesizing neurobehavioural research and music education research to correlate music education with positive behavioural outcomes for at-risk youth and a reduction in juvenile criminal offense rates as well as recidivism at later ages. I predict that the research will support that the earlier and more consistently the individual receives music education, the stronger the correlation with improved performance in school and social situation and lower negative outcomes. In the past few decades, the United States has slipped farther down the list in world rating of education. Music Education programs in public school would benefit all students and lead to higher rates of graduation. To implement this in practice necessitates that music programs be reinstated and expanded in public schools and potentially be available to children as young as three years old in tandem with programs like Jump Start.

The purpose of this research is to increase compliance among undocumented workers and propose an incentive package that will benefit both the U.S. economy and provide a new way of obtaining citizenship for immigrants. This research focuses on the growing “tax gap” in the United States: “What are the effects of undocumented workers and their income on the national and local economies in the United States? What can be done to increase the number of undocumented workers to report their income?” By thoroughly examining various policies and practices related to these matter(s), this study synthesizes wide range finding(s) and outcome(s) of various policies and its output to introduce multiple alternative resolutions to better both parties (Literature Review). This study also further explores the future implication and outcome of the current and alternative policy recommendations related to the “tax gap” and undocumented workers. By examining the report Reducing the Federal Tax Gap: A Report on Improving Voluntary Compliance by the U.S. Department of the Treasury, the startling estimates of unreported incomes in the U.S will be presented. As New Mexico and Utah propose state guest worker programs, I will examine the benefits and disadvantages of their proposed solutions. By shedding light on the tax gap for the past three years and its relationship to undocumented workers income, the anticipated findings will reveal an increase in the tax gap and demonstrate that the currently policy is not effect.

Today there exists a plethora of nutritional information as Americans are increasingly becoming health-conscious consumers seeking to manage their exposure to disease risk-factors through diet and lifestyle changes. The ever-expanding scope of the media and internet, especially through the increased use of popular health blogs and forums has "democratized" nutritional science--making nutritional information more easily accessible. Yet, despite the growing body of research in nutrition made available to the general public, the history of nutritional advice has been notoriously unstable, inconsistent and inaccurate as science, food industries, and various ideologies contend for validation. For example, from the consumption of saturated fats and carbohydrates to raw cow’s milk (which is supposedly "nature's most nearly perfect food" Americans are left confused when making decisions and establishing “truths” regarding the nutritional health benefits of other foods. Because the science of diet and nutrition are highly contested areas of knowledge, the purpose of this study was to delve into the social, cultural, and political aspects of food to better understand how we make sense of nutritional advice. To that end, this research project acquired and synthesized past and current scientific research literature to explore what it means for foods to be "healthy" how one may navigate the massive array of contending knowledge and different dietary models to obtain information on "healthy food" and additionally, how competing corporate interests, scientific findings or interpretations, and anecdotal evidence of the lay consumer may influence nutritional data made available to the public. So far the general trend shows corporate influence supersedes that of medical and scientific advocates; however, more research is required to determine how health consumers navigate the wealth of information. Recommendations for a potential solution at a policy, educational and, or mass media level will also be discussed in further detail.

 Myocardial infarction, heart failure, and congenitive heart disease are leading causes of morbidity and mortality worldwide. However, current cell therapies remain inadequate in addressing this clear medical need. One of the primary obstacles limiting the success of cell therapies is that stem cell derived cardiomyocytes (SCDCM’s) tend to be functionally immature, providing only a small fraction of the force generation of their matured counterparts. Thus, the work here focuses on developing a growth platform which incorporates topographical and mechanical properties in order to rapidly and thoroughly mature SCDCM’s. The field of tissue engineering is becoming increasingly aware of the roll that the extracellular matrix (ECM) plays in driving cellular differentiation and behavior, and the importance this has on the design of biomimetic scaffolds and growth platforms. A study of the native cardiac environment has revealed that the presence of aligned nanoscale matrix fibers plays a key role in establishing organization within the myocardium. This insight has allowed us to construct polymeric scaffolds which mimic the in vivo ECM, greatly improving cardiac culture techniques. There exists an optimal feature size and configuration at which nanogrooved topography is successful in promoting anisotropic alignment and elongation of cardiomyocytes, an increased action potential conduction velocity, and the substantial expression of cell-cell coupling proteins. Our current focus rests on understanding the way in which mechanical and chemical variations to the growth substrate can affect cell morphology and contractile properties when manipulated in conjunction with nanoscale topographical stimulation. This research will provide a strong foothold towards the development of a cardiac patch, which, implanted directly onto the infarct surface of the heart, could reduce scar tissue formation, promote healing and angiogenesis, and provide crucial contractile and mechanical strength.

Fear conditioning is a form of classical conditioning where an initially neutral conditioned stimulus (CS) is paired with an inherently aversive unconditioned stimulus (US). After multiple CS-US pairings, CS alone produces conditioned fear responses. The amygdala has long been considered the key brain structure where fear learning-related plasticity primarily occurs. However, it has not been well studied how the US directs CS-US association in the amygdala. We recently found that stimulation of the dorsal periaqueductal gray (dPAG) could serve as a US in tone fear conditioning, indicating the dPAG may be a key structure in relaying US information to the amygdala during fear conditioning. In this study, we investigated the role of the amygdala in auditory fear conditioning where dPAG stimulation acted as the US. Male Sprague-Dawley rats were bilaterally implanted with stimulating electrodes in their dPAG and with guide cannulae in their amygdala. Prior to training, muscimol (0.3 µg/0.3 µL per side) was infused into the amygdala using infusion cannula and a microsyringe pump. For training, a tone (2.9 kHz, 85 dB, 20 sec) was used as a CS, and electrical stimulation (0.1-ms width, 100 Hz, 2 sec) of the dPAG as a US which co-terminated with the CS. Next day, an 8-min tone was presented continuously in a novel chamber as a tone testing, and the following day, 8-min exposure to the training chamber was given to the rats as a context testing. While the muscimol-injected animals displayed comparable level of freezing to the control animals during training, their freezing to the tone and context was disrupted during the testing, indicating fear conditioning was blocked by the amygdalar inactivation. These results suggest that the amygdala is critical for dPAG stimulation fear conditioning and may be the center of dPAG-directed US and tone CS convergence and plasticity.

Biochar is the product of biomass that undergoes pyrolysis, the process of thermal degradation in the absence of oxygen and is a type of charcoal. Research has shown biochar to be an effective soil amendment but the optimal levels of incorporation are unknown. This study examines if an optimal level for plant growth exists and to determine if introducing a stress factor will alter the optimal point. Five levels of biochar amendments at 0%, 1%, 3%, 5%, 10%, and 15% by volume have been made into root media with high or low nutrient availability as a stress factor. Sweet peppers plants were grown from seed in flats for one month and seedlings were transferred to larger pots with appropriate biochar level. They will be grown for two months and destructively harvested for dry biomass data. We hypothesize the pepper plants will have an optimal biochar level for growth and this level will change with plant stress.

With more than 5 million new infections each year, the HIV pandemic presents a growing problem to which a cure has thus far been elusive. High rates of mutation and variability across HIV strains complicate antibody production via the secondary immune response. HIV surface protein shedding (gp120 and/or gp41) via membrane-proximal external region (MPER) specific antibodies has been shown to neutralize viroid infectivity1, however the conserved MPER of gp41 remains protected by surface proteins, and denatures when removed from its lipid environment. We have developed a vaccine system using lipid bilayer-polymer core virus-like nanoparticles (VLPs) that allows for the delivery of MPER in a native conformation. These VLPs have been controlled for size, polydispersity, and surface characteristics to allow intercalation and presentation of MPER in a hydrophobic state. We plan to characterize cellular uptake and cytotoxicity characteristics of these VLPs using in vitro assays. We will evaluate secondary immune response in a mouse model, examining antibody titers post inoculation. This vaccine platform may prove to be a robust technique for the delivery of hydrophobic antigen moieties, readily uptaken and producing a strong antibody response with low cytotoxicity.

Many neurological diseases that are prevalent in our society, as well as serious addictions, affect one’s ability to make optimal decisions. In order to provide further insight on these conditions, the underlying mechanisms and processes of decision-making must first be determined. Previous research shows that the inactivation of amygdala during bouts of stress blocks any stress effects on later decision-making performance. This study aims to answer how this occurs by determining the necessary brain structures for the decision-making task. Because prefrontal cortex lesions have not disrupted decision making on the task in earlier studies, lesions of subcortical regions should negatively affect decision making. Specifically, we lesion the central and basolateral nuclei of the amygdala, or the dorsomedial striatum of several rats, two subcortical regions known to be strongly associated with reward-related behavior. Decision making is assessed through a series of baseline and bias tests on a figure-8 maze. The rats run through a series of equal-reward baseline sessions on the maze, then switch to bias testing for three days (unequal reward), and finally are tested on reverse bias (unequal reward, larger side switched). It is suspected that significant decision-making impairments will be seen after either the amygdala or the dorsomedial striatum is lesioned.

Human immunodeficiency virus (HIV) has claimed more than 25 million lives worldwide, and a further 33.2 million are currently living with the disease. Current treatment for HIV involves highly active antiretroviral therapy (HAART), which commonly involves the oral administration of a combination of small-molecule drugs that target HIV at different stages in the viral replication cycle. Oral administration requires larger doses of drug due to loss during metabolism, which can lead to greater costs and increased toxicity for patients. To avoid these issues, a lipid-encapsulated hydrogel nanoparticle was synthesized as a mucosal drug delivery vehicle for small-molecule antiretroviral drugs. The nanoparticles, comprising a crosslinked polyacrylamide core surrounded by a phosphatidylcholine bilayer, were synthesized via photopolymerization and characterized using dynamic light scattering for size, zeta potential, and morphology. They were then synthesized encapsulating zidovudine or tenofovir, which are reverse transcriptase inhibitors, or maraviroc, an entry inhibitor, and the encapsulation efficiency and in vitro release kinetics were measured using high-pressure liquid chromatography. In vitro cellular uptake of the nanoparticles was measured using bone marrow dendritic cells (BMDCs). The nanoparticles showed a tenfold increase in the encapsulation efficiency of all three drugs and a slower release profile as compared to liposomes encapsulating the same drugs, indicating that this system allows for HAART dose reduction. The nanoparticles were also taken up preferentially by BMDCs as compared to drug-loaded liposomes and soluble drug, further indicating greater targeted delivery of drugs to infected cells and suggesting a future use for the delivery vehicle as an HIV vaccine.

 Microencapsulation of xenogeneic recombinant cells within Alginate Poly-L-lysine Alginate (APA) matrices is an alternative approach to drug delivery. The APA encapsulation matrix protects xenogeneic cells derived from individuals or species foreign to the host immune system without the need for immunosuppressive or genetic therapy. Furthermore, matrix permeability allows for the continuous delivery of secreted cellular therapeutics at the implantation site. Although this technology is well-established, the ability of these cell-loaded APA particles to secrete antigens activating specific immunity towards HIV over long periods of time has not been studied. My research is aimed at developing implantable, cell loaded microcapsules capable of producing immunostimulatory molecules preventing the transmission of HIV in the genital mucosa. Using cellular viability and quantitative protein assays, my work will examine the long-term stability and protein production of human 293T cells expressing fluorescent HIV pseudovirions. The immunomodulatory effect of cell-loaded APA microcapsules will then be investigated using cell reporter assays. The results of this research may demonstrate the ability of cell-loaded microcapsules to deter HIV transmission over long periods of time by priming the immune system for HIV attack. We expect that this research could lead to studies of the ability of these particles to provide long term protection against HIV infection in animal models. The results of this work may also be applicable for developing vaccination strategies for other sexually transmitted infections.

Hydrogel tissue scaffolds have emerged as a useful tool for extensively mimicking and reproducing the cues of the natural extracellular matrix (ECM) of native cell environments. Polyethylene glycol (PEG) is a synthetic compound that is often used as a hydrogel as it is nontoxic and exhibits strong mechanical properties. PEG, however, does not allow cell adhesion and cannot be degraded by cells. To resolve this issue, the incorporation of denatured collagen, or gelatin, was used. This process was completed via addition of methacrylated gelatin (GelMA) to photocrosslinkable PEG hydrogels. The addition of the polysaccharide hyaluronic acid (HA), which is an integral part of the ECM, is in part a novel approach to further provide chemical cues to activate specific receptors (i.e. CD44) within cells. Moreover, cells have also been known to respond to physical stimuli such as changes in the topographical environment. We have developed a technique to produce a nanotopographic pattern on hydrogel scaffolds via the use of a nanopattern mold. Here, we propose the novel integration of the chemical signals produced from the hydrogel in conjunction with a nanopattern for directing cell migration and proliferation in vitro. In this experiment, Wnt1-Cre derived dental pulp stem cells (DPSC) were cultured on these scaffolds. Cellular regulation was reflected in changes in morphology and migration due to exposure to the combined chemical and physical signals of the tissue construct. Cells cultivated on patterned scaffolds showed significant alignment along the pattern compared to flat controls. In addition, cells on HA-PEG-GelMA hydrogels exhibited aggregation over time to form spheroids that persisted for the duration of the experiment. These findings suggest that the microenvironment of HA-PEG-GelMA hydrogels plays a significant role in regulation of the spatial arrangement of cells.

HIV has infected over 30 million people worldwide and has resulted in the loss of millions in healthcare costs. HIV vaccines have the potential to prevent infection and drastically reduce infection rates. A potential strategy for vaccine development is to elicit a mucosal immune response, since sexual transmission of the virus is the leading cause of new infections. A successful functioning vaccine would deliver an HIV antigen, such as the highly conserved regions of the HIV membrane surface protein gp41, and an adjuvant, such as the synthetic organic molecule R848, through mucosal and cellular barriers. Here, a delivery vehicle for a complex HIV vaccine is synthesized by using a single emulsion method to formulate a polymeric nanoparticle, consisting of a biodegradable polymer core surrounded by a lipid layer. Previous research has shown that a lipid shell increases serum stability and immunocompatibility in vivo. First, design parameters, such as solvent and surfactant properties, were modified to yield consistently monodisperse populations of nanoparticles with controlled size and surface chemistries. Different methods for encapsulating the adjuvant into the polymer core were also explored. The encapsulation efficiency and drug loading of the adjuvant, as measured using liquid chromatography, was less than 1%. We delivered an HIV antigen by intercalating it within the lipid layer surrounding the polymeric core. Encapsulation efficiency of the antigen was measured with a proof-of-concept peptide attached to a fluorophore. We used ELISA and cell culture studies to test for the controlled release and immunogenicity of the immunogens. Finally, a mouse model will be constructed to test the particles in vivo. This project demonstrates a design for creating nanoparticles with controlled characteristics for eliciting a comprehensive immune response against HIV.

The amygdala is a central structure studied in investigations of fear and anxiety because of its crucial role in acquisition, retention and expression of conditioned fear responses.  Lesions of the amygdala before and after training have abolished conditioned defensive fear responses such as freezing, potentiated startle, and 22-kHz ultrasonic vocalizations.  However, pre-training and post-training lesions of the amygdala have not abolished inhibitory (passive) avoidance learning.  The learning of this particular defensive strategy without the amygdala has caused debate amongst investigators.  Our study uses a 2-food lever closed economy (continuous, long-term, semi-naturalistic environment) behavioral paradigm.  Rats have free choice of levers dispensing rat chow closer or farther from the nesting area.  After a baseline of lever-preferences stabilized, 2 footshocks on average were introduced randomly each hour in the foraging area.  Animals could avoid the shock by remaining in the nesting area. Lesions were performed on the basolateral amygdala (BLA) and central amygdala (CeA).  Whereas the introduction of shock in control animals destabilized initial lever preferences, lesioned animals showed an absence of the destabilizing effect and maintenance of initial lever preferences.  Additionally, both amygdalar-lesioned and control rats decreased their time spent in the foraging area , exhibiting learning of passive avoidance behavior . However, only amygdala lesionsed animals showed deficits in a standard Pavlovian fear conditioning task.  Our results demonstrate that in an environment of long-term, unpredictable danger, the amydala is able to modulate defensive behaviors such as optimal foraging behaviors but not inhibitory, passive avoidance response to danger.  Investigation of the amygdala’s role with regard to behavior under unpredictable threats over a long period of time can help us understand various human pathologies involving chronic exposure to unpredictable environmental stress.

Explaining regional differences in real wages has long been a subject of interest to economists. A substantial body of econometric literature offers various explanations for such differences, ranging from labor market characteristics such as unionization to local amenities such as crime levels and average commute times. Another possibility is that labor market wages compensate for constraints placed on the time of residents in a given region. In particular, if the lifestyle in a certain area requires a greater amount of time devoted to non-market labor activities (things such as grocery shopping which are neither leisure nor a labor market job) then perhaps wages must be higher in those areas in order for residents to accept the constraints placed on their time by living there. This paper tests that hypothesis using an econometric method known as hedonic wage-amenity modeling which has become standard in regional amenity valuation literature. Detailed time-use data recently made available by the Bureau of Labor Statistics is aggregated for regional patterns and analyzed against local wages and cost of living for a possible relationship.

Insect-eating animals like birds are considered to be beneficial to farmers, since they help control insect pests. However, it has often been difficult to determine the extent to which agricultural pests make up the diets of predators like birds, since it can be difficult to actually observe them feeding on harmful insects. However, if we collect samples of feces from birds captured in farms, we can use molecular methods to look for the DNA of insect pests in these samples, a method that has been successfully used to study the diets of bats in agricultural areas. We extracted DNA from approximately 200 samples of bird feces and bird stomach contents form birds captured in coffee plantations in 2000 and 2001 as part of a study on the diversity of birds in coffee plantations. However, it has proven difficult to recover amplifiable insect DNA from these samples, possibly due to their age (the DNA is probably degraded). Of the over 200 samples, fewer than 20 have yielded insect DNA. Of these, none have tested positive for DNA from any of the insects that are the worst pests of coffee in our study area. This is in contrast to bats from the same study area; over 10% of fecal samples have DNA from one of these three coffee pests. There are a number of reasons why this might be. First of all, the bird samples were all collected in the dry season (our winter) when there are fewer insect pests. Also, the bird samples were collected in a different year, so there might not have been many pests at that time. Finally, the migratory songbirds might not be the birds that most feed on insect pests.

The spindle assembly checkpoint is important for detecting errors in spindle assembly during mitosis. When the checkpoint is activated, it arrests the cell cycle so that errors such as unattached kinetochores can be detected and corrected before progressing through the cell cycle. Problems with kinetochore attachment can be detrimental and lead to cells with an abnormal number of chromosomes which can then cause birth defects. Misregulation of the cell cycle can lead to abnormal cell division and cancer. Spindle pole bodies in yeast are functionally equivalent to human centrosomes, which organize microtubules in the cell cycle. Spindle pole bodies increase in size when the cell cycle is arrested at the checkpoint. Mad1 is an essential component of the checkpoint and interacts with the Nup60 protein in the nuclear pore complex, a channel through which information traffics between the nucleus and cytoplasm. The N-terminus of Mad1 protein is required to localize Mad1 to the nuclear pore complex, but is not required for the checkpoint arrest. We found previously that if Nup60 is deleted, the spindle pole bodies do not grow in cells arrested at the checkpoint. Mad1 mutants containing only the C-terminus of the protein will be constructed. I will test if the ability of Mad1 to bind to Nup60 is required for spindle pole body growth. Spindle pole body size will be measured by fluorescence microscopy after arresting the cells in metaphase. I hypothesize that although Mad1 interaction with Nup60 is not required for the cell cycle arrest, it is required to signal spindle pole body growth. If true, then deletion of the Nup60 binding domain of Mad1 should block spindle pole body growth. Discovering what interactions are vital in these cells will give us a deeper understanding of how regulation of the cell cycle is maintained.