Both Florinda by Maria Rosa Galvez, and El Eterno Femenino by Rosario Castellanos, are works of theater that focus greatly on the theme of female oppression. In this infographic, we compare this theme within the two works, and the relevance this theme still has today. While both works take place in a patriarchal society, and ultimately end with the unhappiness of their female protagonists, there are differences in the themes they portray. Florinda places focus on the oppression of women by her male counterparts, who abuse their powerful roles in society, and blame her for the crimes taken against her. El Eterno Femenino focuses more on internalized oppression, with stereotypical female roles, and pressures to be a perfect woman and perfect wife, oppress generations of women in society. These works were written more than 150 years apart, with the theme of the oppression of women still very prevalent. We even see this theme carried into the works of today, as women’s rights continue to be a problem in today’s society.
The play “El eterno femenino” by Rosario Castellanos pórtate the live of a women who struggle to finding who she is a a woman. Throughout the play, she encounters many people and events that shape the way she sees her life as a women. In the poster, I drew a women with a child because it is watch women are most related to, their children. On the left side of the poster, there are words and phrases that reveal how society expected women to be. However, on the right side, there are words and phrases of what women wanted to be and what they actually felt. Overall, the message I am trying to portray is that in “El eterno femenino” we can truly see the difference between what women have to go through compared to what they truly want.
Cancer cells rely on glycolysis even under normoxic conditions. The use of this pathway results in measurable intracellular acidification, which is characterized as an early event in the apoptosis program. The pH is restored by activation of voltage- gated proton pumps, preventing acidification. Proton pump inhibitors (PPIs), such as omeprazole, inhibit the H+/K+-ATPase system found at the secretory surface of gastric parietal cells. Research has shown that omeprazole is also capable of inducing caspase-dependent apoptosis in Jurkat T-lymphocytes. However, the effects of PPIs on caspase activity remain largely unknown. The goal of this study was to determine the temporal dynamics of caspase activity in Jurkat cells treated with omeprazole, dexlansoprazole, or esomeprazole for six hours. After the incubation period, cells were held in place by anti- CD71 antibodies on the device’s affinity surface and fluorescence microcopy was used to monitor caspase activity in real time. Caspase activation was observed over a six-hour period with the fluorogenic caspase probe, L-bisaspartic acid rhodamine 110 (D2R). Elucidation of the intensity and timing of caspase activation will be beneficial for evaluating PPIs as potential cancer therapeutics.
Crayfish foraging behaviors can alter aquatic ecosystems. Starvation and time of day are two potential factors that can influence those foraging behaviors, but the interaction between the two variables has not been studied. In this study, we observed the movement of fed and starved crayfish during the day and at night in the presence of both water and food odor. We calculated both total movement and change in movement and predicted more activity when starved and at night. Crayfish did not show a preference for day or night, nor did they display significantly more movement when fed or starved. These results do not match previous literature, meaning that further research on these factors is necessary, especially in Cambarus acuminatus.
To determine the effectiveness of uzarigenin on S. aureus, the agar disk diffusion method was first completed to study the cytotoxicity effect of uzarigenin directly on the bacteria. A cytotoxicity assay was then completed to test the cytotoxicity of the uzarigenin on the human epithelial fibroblasts themselves. After, a TCID50 assay was used to test for a preventative dose of uzarigenin against S. aureus to determine at what dilutions the uzarigenin can protect the cells from infection at least 50% of the time. It was found that there was an average 8.5 mm zone of inhibition compared to a standard 26.4 mm zone of inhibition by tetracycline. Since there may be different diffusion rates, S. aureus may be resistant to uzarigenin. It was also found that the uzarigenin caused cytopathic effects (CPE, changes in the host cell morphology due to infection) on the human epithelial fibroblasts up until a dilution of 10^-6. Additionally, the 10^-6 and 10^-9 dilutions of uzarigenin were effective in combatting an infection from S. aureus, leaving little to no traces of cytopathic effect. However, dilutions further than 10^-9 seemed to be too diluted to combat an infection, which resulted in CPE in all or most of the wells. Furthermore, the preventative dose for uzarigenin against S. aureus was found to be 10^11.2. In conclusion, uzarigenin may be able to be used as an antiseptic.
Myotonic dystrophy type 1 (DM1) is a multi-systemic disease resulting in severe muscle weakening and wasting. Skeletal muscle wasting is the predominant cause of morbidity and mortality and is responsible for 60% of DM1-associated deaths. DM1 is caused by CTG repeat expansion in the 3’ untranslated region of the dystrophia myotonica protein kinase (DMPK) gene. Myokines are proteins that are produced and released by muscle cells in response to muscular contractions. Previous studies indicated that myokine signaling is deregulated in a mouse model expressing expanded CUG repeat (CUGexp) RNA. The goal of this work was to assess muscle-specific differential expression of myokines in mice expressing CUGexp RNA, relative to non-CUGexp RNA expressing control mice. Previously published RNA-seq datasets were compared to determine which putative myokines, identified in skeletal muscle samples of healthy subjects, were differentially expressed in CUGexp expressing mice. Myokines that display significant differential expression at 6, 12, and 20 weeks of repeat expression include the Cx3cl1, Cxcl10, and Gdf5. Primers were designed customary for these genes and specified for regions with constitutive exons to allow consideration of overall expression levels. Primers were then optimized using RT-PCR. The developed primers will be used to validate differential expression levels of these myokines using quantitative RT-PCR. Validated myokines will be assessed in unaffected and DM1 human myoblast cell lines to determine the contribution of these myokines to the skeletal muscle phenotype in DM1.
Resident Curator Programs (RCP) enable an individual, a group of individuals, or an organization, to serve as the curator of a property. Resident Curator Programs can facilitate preservation of historic properties in a county or region with the goal to rehabilitate and maintain sometimes abandoned or underutilized historic properties and ensure that the public will have scheduled access periodically. This process will not only preserve history but provide much needed context for those who appreciate the historical significance these restored properties. This Capstone focused on the Fairfax County Resident Curator program, an excellent program that is designed to preserve historic properties by offering long-term leases to qualified tenants who agree to rehabilitate and maintain these historic resources in accordance with established preservation standards. A curator can be a private citizen, a non-profit entity, or a for-profit entity. Fairfax County’s RCP is intended to reduce the public costs associated with the care and preservation of the properties by enabling groups or individuals to take over the responsibility. In addition to caring for the day-to-day management of the property, the curators are responsible for the rehabilitation and continued maintenance of the property. Properties that are included in the RCP have been deemed historically significant and meet established criteria of eligibility for curator. Any proposed rehabilitation of these sites must meet the Secretary of the Interior’s Standards for Rehabilitation, and the curator must provide reasonable public access to the property. In return, curators pay no rent as long as they continue to fulfill their contractual obligations. Curators are responsible for upkeep, property maintenance expenses, utilities, and county property taxes.
Basic Annual Cable Subscriptions in the U.S. have been declining since 2001, which is the same year Netflix began recording subscribers. The annual number of basic cable subscriptions in the U.S. is calculated based on the total number of subscriptions to basic cable television. This means any extra channel packages or upgrades are not included in this variable, only the bare minimum subscription. The purpose of this study is to determine whether Netflix’s emergence directly impacted the rate of Basic Cable Subscriptions. This research is based on the years 1989-2019, for reference. This study contains has 4 independent variables. Basic Netflix subscriptions, which is the total amount of standard subscriptions on Netflix and should influence the Dependent Variable directly because it is a cable alternative. Basic Cable Subscription cost, which is the dollar amount for a basic cable subscription, no extra packages, or channels. Basic Netflix Subscription cost, which is the dollar amount of the standard Netflix subscription, no upgrades. Lastly, Annual U.S. Household Income, which is the average household income in the U.S. in dollars. In the years prior to Netflix (1989-2000), Basic Cable Subscriptions rose from 49.2 Million to 66.6 Million subscribers, a 35-percent increase. This was the peaking point for Basic Cable Subscriptions and since 2001, their subscriber count has fallen back down to 50.5 Million, nearly a 24-percent decrease. Given that Basic Cable Subscriptions is a normal good and tends to go up with income, seeing in the data that it declined in the past 15 to 20 years as Netflix emerged and grew rapidly draws the conclusion that Netflix directly impacted Cable TV subscriptions. The regression results are able to explain 77% of the variance in Cable TV Subscriptions and only contains Netflix, not any other widely used streaming services.
By Hannah Lee, Sabine Krall, John Tan, Raesa Zia, Charlotte Russell, Jayme Boudreau, Hannah Stottlemyer, Andrew Cooper, Elizabeth Sullivan, Madison DeWitt, Mitchell Freitag, Jacob Cantor, Arianna Chase, Vallarie Burge
Faculty Mentor: Professor Swati Agrawal
Bacillus thuringiensis subspecies Kurstaki (BTK) is often used as a microbial insecticide for pest control and as a simulant for Bacillus anthracis in biowarfare and bioterrorism studies. Students in 2021 Phage Hunters class at University of Mary Washington isolated nine bacteriophages using the host Bacillus thuringiensis subspecies Kurstaki. Two phages, Hari and Jackrabbit, were sent to SEAPHAGES for sequencing are currently being annotated in the lab during the Spring semester. Hari was found in a soil sample obtained from King George, VA while JackRabbit was isolated from Linton, VA. Both samples were isolated from enriched cultures. Hari has a genome length of 161,978 bp, which auto-annotated with 286 features, and a direct terminal repeat of 2,633 bp. Hari is most similar to DIGNKC, SBP8a and PPIsBest by BLAST. JackRabbit has a genome length of 161,552 bp, which auto-annotated with 288 features, and a direct terminal repeat of 2,821 bp.
Mice are socially aggressive animals and tend to interact in ways that are representative of a social hierarchy. Their interactions and behaviors determine their position in the social hierarchy, i.e., dominant, subordinate, or somewhere in-between. The present study examined the effect of social rank on behavior and stress/anxiety. Mice were given access to a running wheel, an important resource because it provides the mice with stress relieving exercise, in both their home cage and their accessory cage. The mice’s daily activities, along with specific tests, were recorded to measure each mouse’s anxiety and identify them as dominant or subordinate. While the social rank of the mice was determined, none of the physiological or behavioral tests performed provided conclusive results demonstrating significant differences in anxiety or response to stress. This could be attributed to several factors, such as the spacious home cages, the accessibility of the isolated accessory cages, and the availability of two running wheels. Said factors possibly created a less stressful environment for the mice. The lack of significant results could also point to the behaviors and tests observed were not appropriate for detecting the effects of social stress in mice.
This project examined the disability services and website accessibility features provided by Virginia libraries. According to the American Library Association’s (ALA) Association of Specialized Government and Cooperative Library Agencies (ASGCLA), there is a “commitment to diversity and to accessibility of library and information services for all, including people with physical, sensory or mental disabilities, as reflected in the ALA policy on library services to people with disabilities (54.3.2)” (https://libguides.ala.org/equip-facilities-mgt/disabilities). During my research, however, it was discovered that while there are noteworthy efforts being made within Virginia libraries, that this commitment is not equal among them, nor is it the best it can be. My research proved this in several ways, but it is with great emphasis that I state that this project is not an attack on the Virginia library system or its individual members, but rather an examination in hopes that further efforts will be made so that all individuals in need can be better served. I performed qualitative observational research of library home pages. This involved crafting a database detailing whether or not these libraries clearly advertised and offered certain disability activities, services, and resources. I utilized a website accessibility evaluation tool known as WAVE to create a database analyzing libraries’ website structure and errors. I also performed quantitative research on municipality budgets and library funding and added this information to the observational database; resulting in my conclusion that money is not the sole contributing factor in the ability to provide services. Lastly, key recommendations were established as a result of my findings so that I can potentially share my research problems and solutions via my newly created Twitter project @openbookva. These infographics are the result of a semester-long research project completed in collaboration with Dr. Brenta Blevins and Mr. Peter Catlin.
Toxoplasma gondii is a microscopic parasitic protist. It is responsible for the disease toxoplasmosis which can cause severe health problems in immunocompromised individuals and babies whose mothers become infected while pregnant. T. gondii is an obligate intracellular parasite that can infect almost any warm-blooded mammal. Because of this, host cell invasion is a key function that T. gondii must perform. Vital to this process is a group of secretory organelles including rhoptries, micronemes, and dense granules. Research has shown that subtilisin-like proteases act in processing and cleaving certain sites on proteins associated with these secretory organelles. T. gondii has a set of 12 genes that code for these proteases. While much research has been done on SUB1 and SUB2, little to none has been done on other genes such as SUB4. To determine the vitality of SUB4 in T. gondii host-cell invasion, I am creating gene knockout mutants using CRISPR-cas9 and will observe their ability to invade mammalian fibroblast cells. I created a drug repair cassette by adding SUB4 homology arms to a drug marker amplified from pJET plasmid. I designed and am currently in the process of amplifying two sgRNAs that flank the gene on both 5′ and 3′ ends. Once these are constructed, I will transfect T. gondii ΔKU80 cells, which cannot perform nonhomologous end-joining repairs, with these vectors to knockout the SUB4 gene. Following drug selection and screening to determine if the parasites successfully recombined the SUB4 locus, I will characterize mutant parasites using microscopy and biochemical techniques. Finally, I will conduct invasion and egress assays to determine the ability of Toxoplasma gondii to invade host cells without expression of the SUB4 gene. I expect that they will invade the fibroblast cells but at a slower rate compared to the wild-type parasites, elucidating the role of SUB4.
Similarly to antibiotic resistance, antifungal resistance is a growing challenge for clinicians. Mechanistically, one method of antibiotic resistance acquisition is through horizontal gene transfer (HGT). Although associated more with prokaryotes, past studies show limited evidence of HGT in Candida yeast, warranting additional comparative, genomic and proteomic research on the evolutionary forces behind fungal virulence. This honors capstone project used the NCBI’s Basic Local Alignment Search Tool (BLAST) to quickly and statistically compare existing biological sequence data in conjunction with EMBL Multiple Sequence Comparison by Log-Expectation (MUSCLE) alignment and Molecular Evolutionary Genetics Analysis (MEGA) to visualize likely evolutionary relationships. Thus, the objective of this project was to use bioinformatics tools to identify potential instances of Horizontal Gene Transfer (HGT) between pathogenic yeast and viruses, specifically HGT as an evolutionary mechanism for antifungal resistance gene (ARG) acquisition. Of the subset of ARGs searched, BLAST showed more support for ERG3 (C-5 sterol desaturase) HGT between edafosvirus and C. glabrata and between orpheovirus and C. albicans and C. californica, respectively. However, the ML phylogeny contradicts these BLAST results and shows more support for ERG3 HGT between both viruses and Hypopichia burtonii. Thus, while BLAST showed limited evidence for ERG3 HGT between three Candida species and two viruses, the ML phylogeny fails to support these evolutionary events. For the purposes of HGT, BLAST might be better suited to certain organisms (i.e., prokaryotes) and its use should be reinforced as a non-definitive predictor of such evolutionary events. Furthermore, increased understanding of the numerous uncharacterized Candida genes could reveal new evidence of fungal HGT and guide treatment options. Word Count: 261
The following student projects, listed by courses from spring semester 2021, are featured on the above linked virtual showcase site.
Professor Laura Wilson – PSYCH 362-01 TITLES: The Association Between Virtual Interactions and Well-being How Adverse Childhood Experiences (ACEs) Affect Participants’ Intentions to be a Primary Caregiver and Anticipated Parenting Styles Instagram Influencer Content and Body Image A Quantitative Study of the Association Between Self-Efficacy and Public Speaking Anxiety in Students Social Buffering as a Moderator of the Relationship Between Anxiety and Attention STUDENT PRESENTERS: Anne Franklin Camila Rodriguez Carrie Van Orden Colleen Cragun Elizabeth Jones Iliana Loaiza Jenna Stewart Katy Rose Price Kendall McCracken Kyle Cassidy Laura String Linda Dick Monica Thompson Nicole Segura Paula Dorca Sydney Dilick Sydney Hassell
Professor Hillary Stebbins – PSYCH 362-02 TITLES: The Effect of Social Anxiety and Approachability on Motivation in Online Classrooms The Effects of Conservatism on Hesitancy Towards Receiving the COVID-19 Vaccine Inherent Curiosity and the Effect of Error Generation on the Ability to Learn German Words The Relationship Between Social Media Self-Presentation, Self-Efficacy, Academic Anxiety, Motivation to Learn, and Camera Usage in Synchronous Virtual College Classes STUDENT PRESENTERS: Amira Akam Amy Rouse Annie Del Zingaro Chloe Billy Kianna Simien Kiara Toler Kira Flinn Lauren Johnson Leonie Steele Lexi Vukmanic Mariana Haugh Marie Bright Rachel Remer Sarah Dietz Sydney Thompson Tenyia Smith Victoria Rulapaugh
Professor Hilliary Stebbins – PSYCH 362-03 TITLES: The Effect of Affirming Scientific Belief on Existential Anxiety How Divorce Conflict Relates to an Adult’s Capacity to Build and Maintain Friendships Mental Well-Being of Varsity Athletes During the COVID-19 Pandemic Parenting Style’s Influence on Sleep Quality and Sleep Hygiene as an Adult The Relationship Between Extroversion, Social Media, In-person Interaction, and Well-being Late in the COVID-19 Pandemic Self Affirmations and the Perception of Micro-aggressions STUDENT PRESENTERS: Aidan Finegan Ally Jones Courtney Haines Courtney Hooker Hannah Hoffman Jackson Kirschner Jasselyn Gallardo-Garcia Madeline Berning Madison Groves Maggie Millar Preston Boxley Shelby A. Russell Siena De Steno Sydney Keating Trimby Magarity Valentina Leon-Ledezma Walker Chilton
Professor Dave Kolar – PSYCH 411-01 TITLES: Educational Influences on Sustainable Fashion Purchasing Behavior Impact of Sustainable Advertising on Individual Behavior Initial Environmental Knowledge and Pro-environmental Advertisements Effects on Purchasing Behavior of Electric Vehicles STUDENT PRESENTERS:
Antonio Herold Chelsie Valencia Ishini Karanda Jenna Whearty Jesse Boles Kevin Bach Malhar Meeran Mekayla Thompson Rachel Beatty Riley Gildea Samia Hajjaoui
Professor Mindy Erchull – PSYCH 411-02 TITLES: The Effect of Parental Division of Labor and Gender/Sex-Based Bullying on Women’s Gender Beliefs, Attitudes, and Behaviors The Investigation of Authenticity as a Moderator in the Relationship Between Conformity to Feminine Gender Norms and Relationship Satisfaction Perceptions of Social Media Influencers Based on Race, Gender, and Interest Perceptions of Women Violating Gender Norms in the Gym STUDENT PRESENTERS: Alyssa Titzer Caroline Hieber Christina Buchanan Corrianna Calloway Dalton Charron Destiny Kay Em Converse Eva Aloezos Gabby Roughan Gina-Marie An Hannah McCarthy Lindsay Fedder Maya Vera Nancy Martin
Professor Dave Rettinger – PSYCH 413 TITLES: Direct and Indirect Peer Pressure and Its Effects on Students’ Opinions about Cheating Effect of Instructor Effort on Students’ Academic Motivation The Effect of Responsibility to Report Cheating on Honor Codes Social Norms Messaging Influence on Student Perception of Cheating STUDENT PRESENTERS: Alexander Lee Alexis Thompson Ashley Stewart Charlene Parker Courtney King Derek DelGross Gretel Kreider Magaly Delgado Mariah Bright Nicholas Graves Olayemi Fadahunsi Rachel Thibodeau Robert Ashworth Teresa Siburn Waverly Atkinson
Professor Virginia Mackintosh – PSYCH 414 TITLES: The Association Between Sexual Orientation and Media on Identity Development Importance of Parenting: Exploring Effects of Parenting Style on Identity Status, Risk Behaviors, and Self-Esteem in College Students Social Media Social Comparison and Identity Development in College Students STUDENT PRESENTERS: Alex Sharpe Anne Spady Carmen Nichols Emma Snyder Grace Gartman Hannah Schmidt Haylee Beish Kennedy King Kourtney Chiles Lucy Bondje Rylie Cole Simone Levendosky
Professor Mindy Erchull – 201-01 Infographic presentations TITLES: All About Blended Emotions The “Athlete’s” Selves The Confirmation Bias During Covid Detecting Deception Emotions Impression Management Self-Regulation Virtual Self-Presentation STUDENT PRESENTERS: Alise Thaler Ann Camp Elizabeth VanSumeren Fabian Rosales Kennedy King Martin Eykamp Tiya Jeffreys Veronica Moore
Ignite talk presentations TITLE: Attractiveness STUDENT PRESENTER: Elizabeth VanSumeren
Professor Mindy Erchull – PSYCH 201-02 Infographic presentations TITLES: Automatic Processing Belief Perseverance Caution: Self-Handicapping Confirmation Bias in Social Media Counterfactual Thinking Heuristics, Biases, and Police Activity Non-Verbal Communication STUDENT PRESENTERS: Ally Holden Andrea McGrath Harper Cowan Krista Rodgers Lovetta Rogers Tyler Clift Veronica Ahmed
Ignite talk presentations TITLE: Commitment and Consistency STUDENT PRESENTERS: Lovetta Rogers WGST 485 A Crumpled Flower: Sexual Assault’s Moderating Effect on the Relationships between Purity Culture, Rape Myth Acceptance, and Mental Health
491/492 Teams (combined list across instructors) TITLES: Color Cues and Consumption: Who Falls Victim to Menu Design? COVID on the Brain: Anxiety Sensitivity and Mindful Awareness Mediate the Relationship Between COVID-19 Obsession and Anxiety The Effects of Shaping on Verbal Behavior in a Simulated Alien Invasion The Influence of Knowledge and Personal Norms on Pro-Environmental Behavior Mindfulness as a Mediator and Moderator in the Relationship between Adverse Childhood Experiences and Depression Mindfulness as a Mediator in the Relationship between Social Media Engagement and Depression Mindfulness in 1st Grade at Riverview Elementary School STUDENT PRESENTERS: Allie Wills Amelia Jones Angeline S. Gnanasekaran Carly Kingston Elsa Baumgartner Emily Beitzell George Stifel Haley McKeen Hannah J. Checkeye Hope Rivers Jenna M. Holland Jennifer Abrahamson Kaitlyn R. Ownbey Kathleen E. Daley Lily Goldberg Madison Schifflet Megan Hook Paige Arnau Purnaja Podduturi Sydney Dahl
This project analyzes cigarette demand in the United States from the years 1964 to 2018. Using the number of cigarette packs purchased in any given year as the dependent variable, a time series OLS regression is run with price, income, population, and the previous year’s dependent variable as the independent variables. Findings indicate price is insignificant, which is common in addictive substances. Income is significant, with its relationship to the dependent variable possibly attributed to societal factors. Population is significant, and its results remain in line with basic economic theory. The independent variable equal to the previous year’s dependent variable is proven to be the most significant factor, which is expected in addictive substances; the total number of smokers in one year, and therefore the number of cigarettes purchased, is heavily dependent upon the number of smokers in the year previous. Cigarette demand in the United States remains complicated by several societal factors, only some of which have been used in this regression. Further, more rigorous research into the reasons for the continued decline of cigarette demand must be completed, especially as new anti-smoking policies arise.
History is often unkind to great thinkers. Often those with brilliant minds are misunderstood in later years by others. This may be the case with the Scottish philosopher Thomas Reid. Reid is the founder of Scottish common sense realism, a school of thought that aims to counter Enlightenment skepticism. However, Reid’s common sense realism was the subject of philosophical debate for years after his death. Many philosophers struggled to understand Reid’s arguments, and others discredited him altogether. While there has been an increase in research on Reid since the 1990s, the contemporary research on Reid is still lacking. Since critical research on Reid’s work is lacking, it is hard to understand the true meaning of his philosophical work. This paper will serve as a complete synthesis of Reid and common sense realism The analysis of Reid will be broken into four sections. The first section sets the stage for Reid’s work by discussing Enlightenment empiricism and rationalism, which Reid’s work was a direct reaction to. The second section will analyze Reid’s major work, An Inquiry into the Human Mind on the Principles of Common Sense, which contains the bulk of his philosophical theory. The third section will discuss the initial reaction to this work from Kant and Hume, two philosophers more famous than Reid that dismissed his work entirely. The fourth section will analyze four Scottish philosophers who lived after Reid and will use their commentaries on Reid to better understand his work, as well as the development of common sense realism as a whole. The goal of this research will be to create a better understanding of Reid’s work and common sense realism.
Aquatic environments require nutrients such as phosphorus and nitrogen to function properly and form the base of complex food webs. However, excess inputs of these nutrients through anthropogenic pollution commonly results in algal blooms, hypoxia, and dead zones. In this study, surface water samples were taken from five sites located around the city of Fredericksburg (City Dock, Old Mill, Ficklen Island, Motts Run Reservoir, and Little Falls). Samples were collected weekly between February 17th – March 24h in 1000mL bottles and analyzed for the presence and concentrations of total phosphorus, nitrate, nitrite, copper, and chlorine using colorimetric assays. During the six weeks of sampling no concentrations of nitrite, copper, or chlorine were detected at any location. Nitrate levels fluctuated at each site with levels ranging from 1.0mg/L to 5.0mg/L. Phosphate was observed to be a cause for concern as concentrations were consistently found at 0.4mg/L to 1.0mg/L in all streams. While the sources of these excess nutrients are unclear, possibilities include excess wastewater treatment facility effluent discharge during heavy precipitation events, construction over waterways that loosens sediment and increases runoff events, and proximity to more heavily populated areas. These results suggest the need for a long-term study to assess what influence seasonal temperatures and precipitation have on nutrient pollution and how these excess nutrient levels impact aquatic organisms in these locations.
The Chesapeake Bay, one of the largest estuary systems on the east coast of the United States, has numerous coal-burning power stations located along its waterways. Coal ash, or fly ash, is a form of industrial waste that is mainly produced by coal-burning power stations and is known to be enriched with trace metals that are at high risk for leaching into waterways, resulting in the presence of these contaminants within aquatic environments. Few studies have examined the distribution of trace metals in the James River watershed, a tributary of the Chesapeake Bay, and the implication of a coal-burning power station located in its upper reaches. Thus, the goal of this study was to evaluate the spatial and temporal distribution of trace metals in both water and sediments within the James River in the vicinity of the Chesterfield power station (Richmond, VA). Water and sediment samples (grab and core) were collected upstream, midstream, and downstream from the Chesterfield power station. The samples were analyzed using ICP-OES (a spectrometer used for analyzing environmental samples for trace metals) for the concentration of twelve trace metals including Al, As, Cd, Ca, Cr, Cu, Fe, Pb, Mg, Mn, Se, and Zn. The preliminary results of water and grab samples show high concentrations of trace metals downstream as well as behind the power station near Dutch Gap Conservation Area. Cadmium concentrations in the water (0.005-0.017 ppm) exceeded the EPA’s MCL’s for drinking water. Complete water and sediment cores samples analyses will provide a clearer picture of trace metals spatial as well as temporal variability and loading at the study site. This study will provide vital information regarding the potential impacts of coal-burning repositories on the presence and mobilization of trace contaminants within aquatic ecosystems and their future impacts on terrestrial and aquatic organisms.
Models used in climate predictions today are dependent on paleoclimate proxies, or recorders of past climate conditions. Eastern oyster shells contain oxygen isotopes that have the potential to be valuable paleoclimate proxies of seasonal changes in the Chesapeake Bay. Numerous oyster shells were found within infilled slave quarters dating to the 1700s at Stratford Hall Plantation. The fact that these slave quarters were backfilled when slavery was still prevalent in nearby regions is surprising. It is hypothesized that localized climate perturbations may have played a role in the abandonment of these slave quarters, as the 1700s took place during the Little Ice Age (LIA), a time when Europe and North America endured cold winters and only mild summers. Oxygen isotopes within the Stratford Hall fossil oyster shells were compared with oyster shells collected in 2019 to test their suitability as paleoclimate proxies and better understand the decline in slave quarters at Stratford Hall. Although the oxygen isotopes were lighter in the fossil oysters, further analysis must be conducted to better understand how differences in salinity between the collection sites of the fossil and modern oysters are affecting the results.
In humans, increased cortisol can lead to pathological increases in blood coagulation, in turn leading to thrombotic events such as deep vein thrombosis and pulmonary emboli. Cortisol appears to promote coagulation by upregulating the transcription of coagulation factors, thereby increasing the likelihood of the coagulation cascade. It is possible that cortisol has a similar effect on clotting in zebrafish, via effects on transcription of coagulation factors. If so, this would support the use of zebrafish as a model organism for testing anti-coagulant medications. I hypothesized that cortisol induces transcriptional upregulation of genes encoding coagulation factors in zebrafish, as in humans. Additionally, that transcript levels of the coagulation factor genes will be higher in stressed females than stressed males. Male and female zebrafish (n=34) were exposed to acute stressors for 7 days, resulting in an unpredictable chronic stress environment. Additional males and females (n=34) were not exposed to the stress environment and were used as control. Twenty-four hours after the seven-day treatment, the fish were euthanized, and their livers transferred to TriReagent. The RNA from the livers was isolated and cDNA synthesized for qPCR. qPCR measured transcript levels of clotting factors X and VII. Mean (SE) Factor VII transcript levels of the control group (-0.211) were not significantly different from stressed groups (-0.367), nor in Factor X control group (-0.100) and stressed groups (-0.576) (p>0.05). Difference in transcript levels between each sex were also determined, with no significant difference in Factor VII control females (0.063), stressed females (-0.583), control males (-0.063), or stressed males (-0.004). No significant difference was found between transcript levels of Factor X control females (0.051), stressed females (-1.361), control males (0.1) or stressed males (0.122) (p>0.05). There is no evidence that increased cortisol causes differences in the transcription of genes coding for coagulation Factors VII or X.
Di(2-ethylhexyl) phthalate (DEHP) is a chiral molecule used as a plasticizer in many commercial products, and its metabolites have been linked to endocrine disruption and other adverse health effects in mice. Differences in the toxicity of the enantiomeric forms are not well studied. In order to synthesize (R,R)-DEHP, 2-ethyl-1-hexanol was reacted with vinyl acetate and Amano Lipase PS in dichloromethane at 0˚C for 48 hours to yield (R)-2-ethyl-1-hexanol (1) (60% yield, 75:25 e.r.) and 2-ethyl-1-hexyl acetate (2) (83% yield). (1) was refluxed with phthalic anhydride and pyridine at 120˚C for 3 hours yielding crude (R)-MEHP (3). After purification via column chromatography, the percent yield of pure (R)-MEHP, confirmed by 1H NMR, was 54% (75:25 e.r.). (3) was reacted with (R)-2-ethyl-1-hexanol (73:27 e.r.), N,N-dicyclohexylcarbodiimide, and 4-dimethylaminopyridine in dichloromethane at room temperature for 20 hours. The resulting (R,R)-DEHP (4) was purified via column chromatography (39% yield, approx. 75:25 e.r.) and confirmed by 1H NMR. (2) was hydrolyzed by potassium hydroxide in ethanol for 30 minutes at room temperature. (S)-2-ethyl-1-hexanol (5) was recovered (105% yield, 83:17 e.r.) and refluxed following the procedure previously described to produce (S)-MEHP (6), confirmed by 1H NMR in 15% yield after purification. Future work will optimize the enzymatic resolution of (1) and explore the reduction of 2-ethyl-2-hexenal by baker’s yeast as a more efficient method for synthesizing (2). Subsequently, the two other enantiomers of DEHP will be synthesized.
Plastic pollution has accumulated to a concerning degree in many of the world’s ecosystems. Microplastics are some of the smallest plastic debris and are generally defined as plastic fragments less than 5mm in diameter. Given their small size, microplastic fibers and fragments can easily enter aquatic ecosystems and the species that feed in or near the water, such as waterfowl. Studies have found microplastics present in the gastrointestinal tract and in fecal samples of several freshwater bird species. Since Canada Geese are commonly found in the Fredericksburg, VA area, I decided to quantify microplastics found in Canada Geese (Branta canadensis) fecal samples in several Fredericksburg locations. I wanted to test the hypothesis that microplastic concentration was correlated to sample location. I obtained fecal samples from Ficklen Island, Old Mill Park, and the parking lot of the Outback Steakhouse in Central Park. The samples underwent digestion in 20 mL of aqueous 0.05 M Fe(II) solution and 40 mL of H2O2 and then vacuum filtrated to isolate microplastics. I then quantified microplastic under a dissecting microscope. There was no correlation between microplastic concentration and sampling location however, the majority of samples contained microplastics. Blue fibers were the most common microplastic type. Microplastics were present in nearly all of the samples supporting the evidence that waterfowl are regularly ingesting microplastics from their environment.
In the US, nearly 24.5 million tons of road salt was distributed across public roadways in 2014. Of the various substances used in these formulations, NaCl accounted for 90% of these treatments. After application, up to 55% of these salts have been shown to enter local waterways via runoff and have been shown to cause many negative effects on the environment including inhibition of algal growth, reductions in activated sludge respiration rates, and mortality in all life stages of some amphibians. However, the effects of NaCl on aquatic invertebrates has been poorly explored. Thus, the goals of this study were to determine 1) the effects of NaCl on Physa acuta egg cluster viability, 2) methods to assess the baseline locomotion behavior of Physa acuta (average mobile speed, average speed, total distance traveled, acceleration, number of frozen events and time spent frozen), and 3) assess the effect of NaCl on these endpoints. Sixteen newly laid egg clusters were collected and exposed to 0, 100, 500, or 1000 mg/L NaCl and viability determined after 15 days of exposure. The locomotor behavior of seven unexposed adult snails were recorded and analyzed using ToxTrac (v. 2.83) to determine the basal movement patterns of this species. To assess the impacts of NaCl exposure on adult mobility, adult Physa acuta (n=3) were exposed to the above treatments for 7 days and locomotor behaviors quantified on days 3 and 7. While this study is still ongoing, it is expected that increased NaCl concentrations will cause a decrease in egg cluster viability and dose dependent impacts on mobility. These findings will help to elucidate the impacts of a commonly used deicing substance on a common invertebrate species.
Myotonic Dystrophy Type 1 (DM1) is a multi-systemic genetic disorder that causes severe muscle weakening and wasting. The phenotype is caused by a CTG repeat expansion in the 3’ untranslated region in the DMPK gene. Studies have shown several different signaling pathways implicated in the DM1 muscle phenotype; however, one pathway that has not been implicated in DM1 is the platelet-derived growth factor receptor beta (PDGFRβ) signaling pathway. PDGFRβ is involved in cell growth, survival, and skeletal muscle hypertrophy. With this involvement, the pathways deregulation could contribute to the muscle wasting seen in DM1. This project uses a fly model to understand the role of the pvr signaling pathway (PDGFRβ fly equivalent) in muscle wasting due to DM1. Through this fly model, it will be determined which downstream pathway is primarily affected during deregulation. The two downstream pathways targeted are PI3K/Akt and Ras/Mek/Erk. Flybase was utilized to determine the downstream gene targets and fly lines needed to start the fly model. After selecting the gene targets, fly lines were picked that were either overexpression of the gene (UAS – upstream activating sequence) or a knockout. Gal4 promoter lines and CTG repeat lines are also needed. Gal4 promoters drive the expression of the desired gene, and the CTG repeat represents the CTG repeat of DM1. With the fly lines chosen, mating schemes were planned to determine what crosses needed to occur to get the desired progeny. The goal was to end up with a progeny with the Gal4 promoter, CTG repeat, and stock line all in the same fly. In the future, using these progeny, different tests will be completed to look at how the overexpression or knockout affects the muscle wasting phenotype.