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Editorial: Voces y Silencios Revista Latinoamericana de Educacion, 15(2)
Get PDFExcerpt from publication: "Cuando empezamos a planear la convocatoria para esta edición especial teníamos en la mente una propuesta que inspirara artículos diversos en contenido, lengua y puntos de vista que reflejaran ejercicios de transformación educativa. En ese momento entendíamos la transformación educativa desde nuestra propia experiencia como educadores/as..."Educatio
Shaping Western Views of Homosexuality in 20th Century Europe Through Community
No full textThis thesis will discuss a community of transnational sexual reformers and their influence on public and private views of homosexuality between the 1890s to the 1930s. This community of sexual reformers had ties to the World League for Sexual Reform (WLSR), an international organization that operated from 1928 to 1935. The WLSR discussed birth control, sexual education, prostitution, venereal disease, and, of course, homosexuality in terms of the law and society. By analyzing the few leading figures who studied homosexuality and sexology at the beginning of the 20th century, I have found that the correspondence and discussion of homosexuality or ‘sexual inversion’ created a transnational network between Britain and the rest of Europe. Many historians have written about these influences from individuals before, but this thesis re-examines this idea from the lens of community. How a community with transnational influences affected the way individuals engaged in ideas of homosexuality in their other social movements. The community and individuals’ efforts for removing prejudice towards homosexuals were ultimately unsuccessful in changing the public on a large scale, but they did give more information to queer individuals about other experiences, reducing isolation.HistoryBachelors of Arts (BA
Assessing the pre- and post-synaptic effects of opioid drugs on breathing rhythmogenesis via population activity mathematical modeling
No full textThis computational study delves into the neural mechanisms governing opioid-induced respiratory depression (OIRD) within the preBötzinger complex (preBötC). The preBötC, in the lower brainstem, functions as the rhythm generator for breathing in humans and all mammals. Neurons of the preBötC comprise the respiratory central pattern generator, producing the rudimentary rhythm and pattern for inspiratory breathing movements. Despite the evolutionary conservation and robustness of this neural oscillator, its Achilles heel is sensitivity to opioid drugs. Here, we present a project assessing the preBötC function relevant to OIRD. Previously, we presented a firing rate activity model of the preBötC that exhibits episodic bursting mediated by the combination of recurrent excitation, synaptic depression, and cellular adaptation (Borrus et al., 2024). To investigate the pre-synaptic and post-synaptic effects of opioids on the preBötC, we extended this model to include two populations that either lack or express the mu-opioid receptor (MOR- and MOR+, respectively), demonstrating synchronization under varying intrinsic excitability of MOR+ neurons. Parameter studies explore how pre-synaptic suppression of excitation, post-synaptic decreases in excitability, and MOR+/- population sizes may contribute to OIRD. Notably, modulating MOR+ excitability slows down the entire system, impacting both MOR- and MOR+ populations. Our findings indicate that inspiratory frequencies decrease with depression of intrinsic excitability, possibly due to the activation of G-protein-gated inwardly rectifying potassium (GIRK) channels. Post-synaptic inhibition analysis reveals that a MOR+ population size exceeding 50% is necessary for opioids to depress rhythmicity. Surprisingly, weaker MOR+ to MOR- connections render the system more sensitive to opioids, possibly because weaker connections render smaller-amplitude activities and higher firing thresholds during inspiratory bursts. Future investigations should consider incorporating calcium channel dynamics and additional respiratory rhythms, such as sigh rhythms, to enhance the model's comprehensiveness. Furthermore, exploring the modulation from MOR- to MOR+ populations and refining synaptic weight interactions could improve the model's accuracy. Despite its limitations in representing these aspects, our model is able to show that the MOR+ population slows the entire preBötC system down and contribute to our understanding on the effects of population size and MOR+ synaptic strength on OIRD.NeuroscienceBachelors of Science (BS
DNA Methylation and the Regulatory RNA HPnc4160 in Helicobacter pylori
No full textBeyond the medical relevance of the gastric pathogen Helicobacter pylori, this gram-negative bacterium is an important model of bacterial transcriptional regulation due to its small genome size. This study aimed to further elucidate how phase variation, DNA methylation, and regulatory RNAs play a role in H. pylori gene expression control. We demonstrated that phase variation in the restriction endonuclease gene hsdR1 controls expression of the downstream DNA methyltransferase hsdM1 encoded in the same operon. To investigate if regulation of this methyltransferase controls DNA-methylation-dependent changes in gene expression, our lab identified DNA methylation sites in H. pylori strain 26695 using a hsdM1 deletion mutant to determine the DNA motif methylated by this enzyme. Traditional epigenetic theory holds that methyl groups physically block RNA polymerase from accessing a promoter to reduce transcription. However, we showed that transcript levels of putative genes methylated by HsdM1 do not change in hsdR1 phase variation mutants, suggesting there may be additional complexity to this system. Our methylome determination also revealed a 5’-RCGDAD-3’ motif methylated at a high level throughout the H. pylori genome by an unknown methyltransferase. Two of these methylated motifs are shortly after the transcription start site for a gene encoding the regulatory RNA HPnc4160, which regulates H. pylori virulence factors including cytotoxin-associated gene A (CagA). We demonstrated that there is a site-dependent effect of DNA methylation on expression of HPnc4160. As expected, DNA methylation of HPnc4160 does not affect cagA mRNA expression, but its effect on CagA protein expression is unclear. However, there is no effect of DNA methylation of HPnc4160 on CagA translocation or interleukin-8 production. Overall, this work highlights the nuance of bacterial gene expression control and delves into the role of DNA methylation and transcriptional pausing in the formation of stable regulatory RNAs.BiologyBachelors of Science (BS
Deeper and Deeper: An Introduction to Seafloor Geology
No full textGrades: 4. Subjects: Earth Science | Oceanography Identifying seafloor features and reading bathymetric profiles.Virginia Institute of Marine Scienc
Quantification Of Poultry And Human Fecal Contamination In The Tidal Creeks Of The Virginia Eastern Shore Using A Multifaceted Edna Method
No full textHuman and animal waste are prominent anthropogenic contaminants in aquatic ecosystems which come from a variety of sources including septic tanks, stormwater, and agricultural runoff. The Virginia Eastern Shore (VAES) is a rural coastal landscape with numerous potential sources of fecal contamination, including an expanding poultry industry and a historical reliance on septic systems. The small watersheds of the VAES combined with agricultural and residential land use in close proximity to tidal creeks make this a model landscape for examining the impacts of upland land use and watershed characteristics on human and animal waste contamination in adjacent waters. However, traditional methods such as the use of fecal indicator bacteria (FIB) to monitor contamination in waterbodies cannot identify the source of fecal contamination. This study developed an environmental DNA (eDNA) source-tracking method using quantitative PCR (qPCR) to detect the 16S rRNA gene from the chicken mitochondrial genome and the NADH dehydrogenase 5 (ND5) gene from the human mitochondrial genome. This new method demonstrated 100% sensitivity and specificity in chicken and human feces and was subsequently applied to six tidal creeks on the VAES with varying levels of upstream poultry operations and residential development. Overall, chicken and human fecal contamination was widespread across the VAES, with levels of human contamination exceeding those of chicken contamination. Metabarcoding analysis of mammalian mitochondrial 16S rRNA genes identified cattle and domestic dogs as additional sources of fecal contamination. Chicken fecal contamination was found in creeks with poultry operations and manure application upstream, while human fecal contamination was highest in a creek with high population density and failing septic systems. Temporal patterns in chicken fecal contamination followed the general trends of broiler chicken production and manure application in Virginia, with a decrease in summer. Human fecal contamination was highest in summer, which coincided with the influx of tourists to the VAES; contamination and tourism were lower in Summer 2020 compared to Summer 2021, most likely due to the COVID-19 pandemic. Data were used in an Information-Theoretic approach to develop multiple linear regression models to predict human and chicken fecal contamination as a function of watershed characteristics; the human model was driven by temperature and population density, while the chicken model was driven by agricultural land cover and fecal coliforms. Models were used to scale fecal contamination across the entire VAES and estimate the impact of changes in anthropogenic land use. While both models predicted increases in contamination with increasing anthropogenic activity, human fecal contamination was less sensitive to these changes. Although these models are in the beginning stages of development, this proof-of concept approach provides a framework for scaling fecal contamination measured at specific sites to a larger region, and to estimate fecal contamination as a function of changes in anthropogenic land use. The integrative use of eDNA analysis and statistical modeling, together with traditional water quality monitoring data and GIS analysis, is a powerful approach for examining fecal contamination and analyzing the effects of anthropogenic land use changes on the water quality of downstream coastal ecosystems.Virginia Institute of Marine ScienceDoctor of Philosophy (Ph.D.
Introducción a la Edición Especial en Castellano de la Revista ISPRESC
No full textLa Sociedad Internacional para la Investigación y Evaluación de Políticas en Orientación Educativa (ISPRESC) tiene entre sus objetivos fomentar la investigación en orientación educativa y la evaluación y desarrollo de políticas públicas en materia de orientación. Para ello, ISPRESC promueve la generación y diseminación de información científica-humanística, así como la colaboración con profesionales de la Orientación y afines, centros formadores de orientadores, líderes de organizaciones de Orientación, y con instituciones y servidores públicos interesados en el desarrollo de la Orientación como disciplina y profesión prestadora de servicios humanos a la sociedad. Para ISPRESC, los profesionales de la orientación en general y los orientadores educativos en particular son los responsables por guiar las tiernas almas humanas hacia luminosos caminos de evolución y civilización. A partir de estos planteamientos y con gran inspiración, la Revista de ISPRESC publica la primera edición especial en Castellano. En el mundo Hispano hablante, sobre todo en la América Hispana, y a pesar de la existencia de diferentes conferencias científicas y asociaciones, una de las situaciones que más repercute en el desarrollo de la orientación como disciplina científica y praxis profesional es la deficiencia en la sistematización y difusión de los conocimientos y las experiencias que tienen lugar en la región. El problema no es solo entre países, sino también a lo interno de estos. Paralelamente, otra situación refiere a la necesidad de mayor participación de los orientadores en el diseño, implementación y evaluación de las políticas públicas que impactan su campo profesional. Parece ser una cuestión de educación, es decir, pareciera que los orientadores no han sido formados para involucrarse activamente en aquellos asuntos de Estado que determinan la formación, los procesos y los servicios de orientación. En este sentido, la primera edición especial en Castellano de la Revista aspira a atender referidas situaciones trayendo un conjunto de artículos elaborados por profesionales e investigadores autóctonos que describen la evolución de la orientación en el sistema educativo y algunas experiencias y contribuciones al desarrollo de conocimientos por parte de los orientadores hispanoparlantes. Anhelamos que esta edición inspire la producción científica-humanística en orientación, legislación y políticas públicas. Se espera que esta publicación se convierta en un haz de luz que permita el andar mancomunado de los orientadores en la necesidad de atender sus propios asuntos, evitando que otros definan lo que constituye la filosofía, los conocimientos y las prácticas de los orientadores, lo qué hacen y el para qué lo hacen. Asimismo, se desea comentar sobre el Dr. Julio González, orientador venezolano que en 2023 dio su último suspiro. Fue un reconocido profesor de la Universidad de Carabobo, así como investigador y promotor de la orientación en Latinoamérica y el resto del mundo. Con su profesionalismo y buen humor ayudó a la integración de los orientadores latinoamericanos y su vinculación con orientadores de otras latitudes, ocupó importantes cargos en organizaciones como la International Association for Educational and Vocational Guidance y la Red Latinoamericana de Profesionales de la Orientación. Su partida fue sentida por la comunidad de orientadores, pero su trayectoria sirve como ejemplo de superación y abnegación en una profesión que en esencia busca la construcción de una mejor sociedad compuesta por individuos sanos, independientes y conscientes de sus derechos como personas y sus deberes para con el desarrollo de la humanidad. Al Dr. Julio González se dedica esta edición especial. Agradecidos y seguimos marchando hacia adelante. ¡Orientadoras y Orientadores, manos a la obra
"You Can Laugh And Let Your Hair Down In This Space": A Qualitative Multiple Case Study Investigation Of The Creation Of Homeplace Between Black Adolescent Girls And Black Women School Counselors
No full textThe purpose of this qualitative multiple case study was to explore the creation of Homeplace between Black women who recently graduated from high school and their former high school counselors who were also Black women. Additionally, this study strove to examine the perceived benefits of experiencing Homeplace in the relationship with their former school counselor for the Black women who recently graduated high school. Homeplace is an environment created by Black women where they can resist oppressive systems, affirm one another, and experience wholeness together (hooks, 1990). Womanism was utilized as the theoretical framework for this study and served as the lens through which the data was analyzed. Major elements of Womanism, including boldness, love, connection, and collective care were considered throughout this process (Walker, 1983). Data analysis revealed four themes: Shared Identities and Experiences, Addressing the Hidden Curriculum, Collective Care and Freedom in Relationship. These findings were explored through a Womanist theoretical framework. In the final chapter of this study, the researcher discussed several implications for school counseling and counselor education and recommendations for future research that were informed by the findings of this study.EducationDoctor of Philosophy (Ph.D.
Security and Interpretability in Large Language Models
No full textThis honors thesis was written and accepted for departmental honors in Computer Science, also serving as partial fulfillment for the author's computer science minor. A second thesis (not honors) was written and accepted for partial fulfillment of the author's Bachelor's of Science in Physics. The second thesis, titled Data Analysis and Machine Learning on DIRC Hit Patterns for PID, explores a different application of neural networks: enhancement of subatomic particle classification methods through a novel neural network architecture, the Swin vision transformer.Large Language Models (LLMs) have the capability to model long-term dependencies in sequences of tokens, and are consequently often utilized to generate text through language modeling. These capabilities are increasingly being used for code generation tasks; however, LLM-powered code generation tools such as GitHub's Copilot have been generating insecure code and thus pose a cybersecurity risk. To generate secure code we must first understand why LLMs are generating insecure code. This non-trivial task can be realized through interpretability methods, which investigate the hidden state of a neural network to explain model outputs. A new interpretability method is rationales, which obtains the minimum subset of input tokens that lead to the model's output. Through obtaining rationales of insecure code, we are able to investigate the relationship between model inputs and LLM-generated insecure code tokens to further efforts in mitigating cybersecurity risks currently posed by LLM-generated code. Our experiment conducts a case study on two common, pervasive, and severe real-world weaknesses: XSS injection (CWE-79) and SQL injection (CWE-89). We first collected data, then obtained rationales for our weak Python code samples via the greedy rationalization algorithm and a GPT-2 model. Thus, we were able to identify the specific tokens which lead to insecure token generation. We also explored an aggregation function for code rationales - structural code taxonomy - which allowed us to investigate rationales on the local and global levels. Our prototype study found good results: rationales for CWE-79 and CWE-89 code samples have different structural code taxonomy mappings. This implies that each LLM-generated weakness arises from different aspects of the code context, and thus efforts to mitigate insecure LLM-generated code must be precisely targeted to the weakness.Computer ScienceBachelors of Science (BS