19468 research outputs found
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Investigation into Amine Polyynes for Antibacterial Properties
No full textAntibiotic resistance is a growing problem in today’s society. Many new antibiotics are derived versions of pre-existing antibiotics, which allows for antibiotic resistance to arise. To combat this issue, it is crucial to elucidate novel antibiotics with unique core structures and mechanisms of action. Asymmetric polyacetylenes have been isolated from natural products, and they have previously been demonstrated to exhibit antimicrobial and antibacterial activity. Solid-supported chemistry was utilized to efficiently synthesize a library of polyynes in a chemoselective fashion. Specifically, amine derivatives of the previously discovered biologically active polyynes were prepared and assessed for biological activity. Many of these compounds displayed improved activity in bacterial viability assays and may be a promising avenue for the development of novel antibiotics. Further investigation is needed to pinpoint the specific structural components that elicit biological activity.ChemistryBachelors of Science (BS
Omnivorous Women’s Perceptions of Vegan and Vegetarian Men as a function of their Dietary Motivations
No full textPrevious research has established that women find vegetarian and vegan men to be less desirable than their omnivorous counterparts. Historically, it has been theorized that this disparity occurs because women are attracted to gender-role-conforming, traditionally masculine men. However, there is a lack of research investigating other potential mechanisms that may impact the attractiveness of vegans and vegetarians. The current study exposed omnivorous women (N = 509) to six vignettes depicting omnivores and either vegans (n = 260), or vegetarians (n = 249), to determine whether diet is associated with perceptions of masculinity and attractiveness. Additionally, we determined whether common motivations for vegetarianism and veganism, which include animal welfare, environmental concerns, and personal health, moderate women’s ratings. We found that women perceived omnivorous men to be more attractive and masculine and were more willing to date these men relative to vegan or vegetarian men. This effect was stronger for women who were high in vegetarian threat relative to those who were low in vegetarian threat. Moreover, men who were motivated by personal health reasons (regardless of dietary preference) were perceived as more masculine. This study provides additional insight into the social perceptions of vegetarians and vegans. Keywords: Attractiveness, Masculinity, Gender Roles, Vegans, Vegetarians, Vegetarian threat, Dietary MotivationsPsychologyBachelors of Science (BS
Health Characteristics of Pregnant Women with Opioid Use Disorder and Their Infants
No full textBackground: Pregnant women who have opioid use disorder (OUD) are a growing population at elevated risk for poor health outcomes, including miscarriage or stillbirth, infections, chronic diseases, and psychiatric conditions. Few studies exist in the literature that simultaneously consider maternal and infant health outcomes when quantifying the effects of OUD and correlated risk factors (e.g., socioeconomic disadvantage, polysubstance use). Our study leverages medical records to provide a rich description of mother-child health outcomes in the context of prenatal substance exposure. We hypothesized that both mothers and infants would experience high rates of health complications during pregnancy, labor, and delivery; we also hypothesized that substance use variables would be significantly associated with both maternal and infant outcomes. Methods: Participants were 54 mothers of 55 infants undergoing treatment for OUD who were enrolled in a longitudinal clinical trial of an attachment-based parenting intervention. Measures of prenatal substance use were examined in tandem with information gathered from maternal medical records to describe the incidence of different maternal obstetric, physical, and psychiatric outcomes and select infant outcomes. Comparisons between this sample and community samples were performed using single-sample t-tests. Independent samples t-tests were used to investigate the various effects of insurance coverage, substance use, and methadone exposure. Researchers performed correlations to relate maternal and infant outcomes from data on substance use and followed up on significant correlations with multinomial regressions, controlling for demographic variables. Results: The current sample was characterized by elevated socioeconomic risk and poor maternal health outcomes, including high rates of obstetric complications, physical health problems, and psychiatric conditions. Mothers in our sample had significantly higher rates of negative obstetric outcomes, depression, and Hepatitis C than in seen pregnant community comparisons. In contrast, infants largely met normal growth and health benchmarks. Substance use did not significantly predict maternal health outcomes in our sample, but methadone exposure and polysubstance exposure significantly predicted infant birth outcomes. Conclusion: The current study highlights the particular health outcomes that mothers with OUD and their infants may experience and reinforces existing data that correlates poorer infant outcomes with in-utero substance exposure. Ongoing data collection will allow researchers to draw more accurate comparisons and conclusions regarding the effects of substance use on maternal health.NeuroscienceBachelors of Science (BS
Quantifying Blue Carbon Storage of the Two Dominant Temperate Seagrass Species in the Lower Chesapeake Bay
No full textSeagrass meadows provide key ecosystem services including storing carbon long-term by trapping and burying organic matter in the sediments. Carbon storage likely differs by dominant species within a seagrass meadow, although quantification only exists for a few key species, including those in the Zostera genus. This lack of quantification presents an important issue in the context of changing species distributions due to climate change. One such example is in the Western Mid-Atlantic, where rising summer temperatures in the lower Chesapeake Bay have shifted the dominant seagrass species from Zostera marina to Ruppia maritima, a species more tolerant to heat waves. The carbon storage potential of seagrass meadows dominated by Ruppia is unknown but thought to be lower than those of Zostera due to plant morphology and life history differences. Here, we quantify the carbon stored in Zostera and Ruppia-dominated meadows of the lower Chesapeake Bay. Forty-two sediment cores were collected from seagrass meadows of varying ages for both species and processed for percent organic matter and carbon stocks. We found that Ruppia-dominated meadows had a higher percent carbon content in the top 5 cm of their sediment compared to Zostera-dominated meadows. Aboveground biomass was positively correlated with percent carbon content in Zostera-dominated meadows but not in Ruppia-dominated meadows. Canopy height was positively correlated with percent carbon content in both Zostera and Ruppia meadows. However, aboveground biomass and canopy height were significantly higher in Zostera meadows than in Ruppia meadows despite the lower percent carbon content. Our results suggest that environmental variables may also be responsible for carbon storage in Ruppia and Zostera meadows, along with seagrass morphology. Our study quantifies the carbon stocks of an understudied seagrass species and aids in understanding the implications of species identity on the carbon storage potential of seagrass ecosystems.BiologyBachelors of Science (BS
Microbial Mediation of Pollen Germination: A Hidden Driver of Plant Reproduction and Hybridization in Asclepias
No full textSexual reproduction in plants is essential for species survival. It is a complex process that extends beyond pollen transfer by pollinators. This study focuses on post-pollination events, examining how stigmatic secretions, and the potential microbes within them, affect pollen viability and germination. To do this we utilized Asclepias as a model system, its pollen is packaged into pollinia which are visible to the naked eye, and its stigmatic secretion is accessible and readily produced. Experimentally, pollinia from Asclepias syriaca, Asclepias exaltata and naturally occurring hybrid individuals were germinated in artificial and field collected nectar. DNA was extracted and sequenced from nectar samples to identify microbial communities, while whole nectar was plated to quantify microbial abundance. We found that both sugar concentration and nectar species significantly influence the ability of pollinia to grow pollen tubes. A. exaltata serves as an effective pollinia receptor, while A. syriaca appears to be a strong pollinia donor. This asymmetric pollinia germination potentially contributes to previously observed patterns of biased introgression between these species. The microbial communities associated with A. syriaca and A. exaltata differ significantly in both composition and abundance. A. syriaca nectar contains a high concentration of bacteria and fungi, whereas A. exaltata contains minimal levels of fungal microbes. These results indicate that microbes may be playing a previously unidentified role in sexual reproduction in plants, specifically, through impacting pollen germination. Microbial communities may be functioning as a prezygotic barrier, potentially acting asymmetrically and impacting the direction of gene flow and evolution. Beyond ecological implications, this study highlights an underappreciated role of stigmatic secretions and their associated microbes in agricultural systems. Given that successful sexual reproduction is essential for crop productivity and global food security, further investigation into these microbial influences is necessary.BiologyBachelors of Science (BS
A Comparison Between the Evolutionary Genomics of Pseudophosphatases MK-STYX and STYX
No full textMK-STYX [MAPK (mitogen-activated protein kinase) phosphoserine/threonine/tyrosine-binding protein] and STYX (serine/threonine/tyrosine-interacting protein) are both pseudophosphatase members of the dual-specificity (DUSP) subfamily of protein tyrosine phosphatases. They are catalytically inactive due to mutations at critical residues in their signature motifs. The histidine and cysteine residues of MK-STYX are replaced by phenylalanine and serine, and the cysteine residue of STYX is substituted by a glycine. Nonetheless, they both have significant roles in cell signaling. MK-STYX has been reported to regulate stress granule formation, neurite formation, and apoptosis. STYX is an important signaling molecule in spermatogenesis, the SCF-dependent ubiquitination activity, and the MAPK/ERK pathway. Recent studies show that MK-STYX and STYX are oncogenes marked in glioblastoma and breast cancer, respectively. Our study analyzes the significance of MK-STYX and STYX by measuring and comparing their evolutionary conservation. Their phylogenetic trees were constructed to show any deviation from the species evolutionary paths. Data was collected on a large set of proteins that have either one of MK-STYX’s two domains, the dual-specificity (DUSP) domain and the cdc-25 homology (CH2) /rhodanese-like domain. Then, we calculated the distance between species pair for MK-STYX and STYX’s protein sequence and Ka/Ks ratio and ranked them among the larger set of related proteins, including MK-STYX’s active homologs MKP1 and MKP3. MK-STYX has one of the highest species-species protein distances, and it is under weaker purifying selection pressure than most proteins with its domains. In comparison, the protein distances of STYX are lower than 82% of the DUSP-containing proteins, and it is under one of the strongest purifying selection pressures. Furthermore, we also demonstrate that there is similar selection pressure on their N- and C-terminal sequences. Our study reveals striking distinctions between the evolutionary patterns of MK-STYX and STYX and provides evidence to further explore MK-STYX’s properties.BiologyBachelors of Science (BS
Solidarity in Protest: A Case Study of the Brown Grove Community in Virginia
No full textThis research interrogates how solidarities are formed within communities as external anti-Black racism and class dynamics put pressure on communities who are grappling with internal division based on generational differences. In my research I’ve learned that social media provides an avenue for community connection through a realignment of values, but simultaneously has the ability to fracture these bonds. Some social scientific literature theorizes that successful protest is drawn from the teachings of the older generation. However, I have found that younger generations play a key role in creating and maintaining successful protest in the midst of division. To better understand this division, I draw from decolonizing and Marxian theorists (Mbembe 2003, Marx 1969) as well as theorists who discuss race and racism and class in their works (Fields and Fields 2012, Taylor 2016, Shange 2019) as they deconstruct power relations. My research is based in the small majority African American community Brown Grove located north of Richmond, Virginia. Specifically, I have observed how community members, who had recently lost their battle to stop a large Wegmans distribution center, interpret division within their own community, and the ways in which they themselves have tried to overcome this division. Community members tell me that using social media creates new possibilities for overcoming internal differences. Despite the power of social media to unite a community, I find that solidarity alone doesn’t necessarily create a successful movement. Rather, I argue that successful protest originates not only from community unity, but through a reevaluation of values and realignment towards collective interests within and outside of the community, as community members aim for possible change.AnthropologyBachelors of Arts (BA
Delineating the Role of Osgin1 in Tissue Regeneration and Wound Healing in Xenopus laevis
No full textEmbryonic development occurs through the cooperation of complex pathways that govern processes of cell proliferation and differentiation. Reactive oxygen species (ROS) play a crucial role in development because while some processes of oxidative stress are necessary for proper development, an overabundance of oxidative stress can harm the embryo. Through transcription of antioxidant genes, oxidative stress is regulated within the embryo. One such gene, Oxidative Stress Induced Growth Inhibitor 1 (Osgin1) has been shown to be upregulated in response to ROS. In order to understand the roles of this gene in embryonic development and tissue repair, whole mount in situ hybridization was performed to study spatiotemporal expression patterns. My data suggests a possible role for Osgin1 in neurodifferentiation and embryonic development.NeuroscienceBachelors of Science (BS
Non-Canonical Amino Acids for Multivalent Conjugation and Light-Mediated Protein Modulation
No full textNon-canonical amino acids (ncAAs) present a powerful tool for introducing novel chemical functionality to proteins. Specifically, ncAAs can be introduced into proteins as handles for the synthesis of site-specific, homogeneous protein conjugates, which have potential applications in therapeutics, imaging, and diagnostics. In this thesis, a method is developed for the synthesis of site-specific, multivalent bioconjugates using a single ncAA. Next, the potential of alkynyl-ncAA bioconjugations, including the Glaser-Hay bioconjugation developed by our lab, is expanded on by investigating novel reactivity of aminooxy groups with monoalkynes, bromoalkynes, and 1,3-diynes. The results of this work involve several new methods of bioconjugation, including multivalent conjugation. Finally, progress is made towards using photoreactive ncAAs for the interrogation of the protein-protein interactions of MEMO1 and for light-mediated regulation of Cas9 gene editing.ChemistryBachelors of Science (BS
Adverse Childhood Experiences, Distress Tolerance, and Non-Suicidal Self-Injury: A Cross-Sectional Mediation Model Among College Students from Six Countries
No full textNon-suicidal self-injury is defined as the deliberate, direct, and socially unacceptable destruction of body tissue without suicidal intent. Global estimates have shown high onset and frequency of NSSI in adolescents and is considered to be an issue of significant cross-national prevalence. Adverse childhood experiences (ACEs) have displayed strong empirical linkages to NSSI; however, more research identifying mechanisms linking ACEs to NSSI is needed. The present study examined the associations between ACEs, distress tolerance (DT), and NSSI severity among college students from six countries. Specifically, we examined whether ACEs predict past year NSSI severity via distress tolerance. Participants were 811 college students (78.4% female) from six countries (USA, Argentina, Spain, South Africa, England, Canada) who endorsed past year NSSI and completed study measures. Within our estimated model, we found that higher ACEs scores were associated with lower DT, which in turn was associated with greater NSSI severity (indirect β = .03, 99% CIs=0.01, 0.06). When accounting for DT, higher ACEs scores were still associated with greater NSSI severity (direct β = .23, 99% CIs = 0.14, 0.31). When testing for model invariance, we found that all effects were consistent across country and sex at birth groupings. These findings suggest that introducing and strengthening healthy coping mechanisms may provide emerging adults who experienced ACEs with adaptive strategies to manage distress and may reduce incidence of NSSI as a result.PsychologyBachelors of Science (BS