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A new perspective on the taxonomy and systematics of Arvicolinae (Gray, 1821) and a new time-calibrated phylogeny for the clade
No full textBackground. Arvicoline rodents are one of the most speciose and rapidly evolving mammalian lineages. Fossil arvicolines are also among the most common vertebrate fossils found in sites of Pliocene and Pleistocene age in Eurasia and North America. However, there is no taxonomically robust, well-supported, time-calibrated phylogeny for the group.Methods. Here we present well-supported hypotheses of arvicoline rodent systematics using maximum likelihood and Bayesian inference of DNA sequences of two mito-chondrial genes and three nuclear genes representing 146 (82% coverage) species and 100% of currently recognized arvicoline genera. We elucidate well-supported major clades, reviewed the relationships and taxonomy of many species and genera, and critically compared our resulting molecular phylogenetic hypotheses to previously published hypotheses. We also used five fossil calibrations to generate a time-calibrated phylogeny of Arvicolinae that permitted some reconciliation between paleontological and neontological data.Results. Our results are largely congruent with previous molecular phylogenies, but we increased the support in many regions of the arvicoline tree that were previously poorly-sampled. Our sampling resulted in a better understanding of relationships within Clethrionomyini, the early-diverging position and close relationship of true lemmings (Lemmus and Myopus) and bog lemmings (Synaptomys), and provided support for recent taxonomic changes within Microtini. Our results indicate an origin of similar to 6.4 Ma for crown arvicoline rodents. These results have major implications (e.g., diversification rates, paleobiogeography) for our confidence in the fossil record of arvicolines and their utility as biochronological tools in Eurasia and North America during the Quaternary
Embodying borderlands: Material practices in contemporary Latinx sculptures
No full textSince the 1960s, artists have created artwork in response to the U.S.-Mexico border. Throughout the late 20th century, both the United States and Mexico, artists used a variety of mediums to communicate social, political, and geographical concerns, such as printmaking, muralism, photography, installation art. Many of these concerns have endured into the present day, though there is a shift in mediums and methods through which these issues enter the contemporary art world.
In my thesis, I explore the material components of sculptures by Margarita Cabrera, Camilo Ontiveros and Guillermo Galindo– artists of Mexican descent now living and working in the United States. Their artwork details the lived experiences of migrants and their loved ones as they are affected by policy, violence, and the government agencies that oversee their legal status in the United States. Their artworks incorporate various found, loaned, and reused materials including empty bullet casings found along the border, border patrol uniforms, and the personal property of a young DACA recipient who was deported in 2017. By tracing the threads of materiality, embodiment, and political resonance, my thesis analyzes how their artworks negotiate trauma, violence, and survival. Moreover, their works conceptualize migration itself as an embodied experience through three dimensional conditions
Tuning bank-full flow duration to modern drainage conditions in moderate to large drainage areas as a tool for reducing error in ancient source-to-sink mass flux calculations
No full textRevival of interest in the source-to-sink method has produced several applications, resulting in new techniques to estimate sediment flux from catchment areas. Each of these techniques are limited by order-of-magnitude uncertainties, requiring new research effort. Initial work by Wilson tuned bank-full-flow duration to the variables cross-sectional area, drainage area, and climate in drainages up to 30,000 km2, and found correlations that could be used to better predict bank-full duration in the ancient where these variables were known. In this research, 94 major rivers worldwide have been subsampled to look at these variables for larger drainages. There is an overall improvement between all correlations where the data is binned by major climate. Other correlations that Wilson observed in smaller drainages hold true in larger drainages. For example, larger drainages show a correlation between bank-full duration and drainage size when binned by climate
Acne and Diet: Association and Significance
No full textResearch Question: Do adults with moderate to severe acne have a higher intake of animal products and fatty/sugary foods when compared to adults with mild or no acne?Background and Significance: Acne is estimated to be the eighth most prevalent disease worldwide and carries a tremendous negative burden on the quality of life for patients. It has been demonstrated that acne is associated with increased risks of depression, anxiety, and suicidal ideation. There has been an increasing number of research studies aimed at assessing the relationship between diet and acne; however, this is an area that remains controversial and has been debated for years. Since the Western diet is well known for its high caloric intake and high intake of saturated fats, it becomes quite relevant to explore its potential association with acne.Materials and Methods: Our cross-sectional study consisted of patients at the Arlington Center for Dermatology and current undergraduate students at Texas Christian University to ensure a spectrum of acne severity was included, both untreated and treated. Participants’ acne severity was measured utilizing the Acne Symptom and Impact Scale (ASIS), a validated and reliable patient-reported measure for acne, and participants’ self-reported current acne severity. Participants were also given a detailed questionnaire regarding their dietary intake. The participants’ Body Mass Index (BMI) was calculated from self-reported weight and height measurements. Data analysis regarding the ASIS questionnaire scores and its possible correlation with self-reported acne severity was conducted via a one-way analysis of variance (ANOVA) at an alpha level of 0.05. Data analysis regarding the participants’ ASIS score and their dietary intake was completed utilizing Microsoft Excel and the Analysis ToolPak add-on. The Bonferroni correction was utilized to reduce the risk of type 1 errors in analysis. All error bars report the standard error of the mean.Results: The participants’ scores on the ASIS questionnaire generally matched with the participant’s self-reported acne severity at a significance level of 0.05, allowing us to utilize the participants’ ASIS scores as a reliable marker of participants’ acne severity. Analysis of BMI versus impact factor resulted in no correlation in a linear plot (r = 0.06). Those who reported an eating frequency of red meat of “several servings per week” and “once per day” had higher ASIS scores than those who reported an intake of “never”. Consumption of artificial sweetener revealed a similar trend in ASIS scores between those who reported an intake of “never” having lower ASIS scores when compared to those who reported an intake of “several servings per month” and “several servings per week”.Conclusion: Establishing lifestyle-based interventions that are without side-effects can significantly improve quality of life for a vast number of patients and aims to treat underlying causes of acne rather than focusing on symptom management. Dermatologists can use this nutritional study to gain a better understanding of how diet can influence skin health and provide further care for their patients. Lastly, the costs associated with acne exceed $1.2 billion and having a cost-effective treatment option is extremely beneficial
Disclosure of tax-related critical audit matters and tax-related outcomes
No full textGiven that tax-related critical audit matters (tax CAMs) were prevalent among accelerated filers (18.5% of observations) during the initial year of CAM disclosures, we examine whether an auditor's disclosure of tax CAMs is associated with variation in tax-related financial reporting quality, tax avoidance, and tax-related earnings management. Finding an association between tax CAMs and one of these tax outcomes would indicate that the new auditor reporting standard has indirectly affected investors. Examining the first year of CAM disclosures, we do not find that tax CAMs are associated with broad proxies of tax-related audit or financial reporting quality (e.g., restatements, internal control weaknesses, comment letters) or tax avoidance (e.g., effective tax rates or book-to-tax differences). We do find that tax CAMs are associated with a modest increase in tax accrual quality, an increase in the reserve for unrecognized tax benefits, and a reduction in the likelihood of tax-related earnings management. However, we do not find these tax CAM effects persist into the second year of CAM reporting. Our evidence is consistent with tax CAM disclosures having a modest but short-lived effect on companies' reporting of tax accounts. Our findings should inform the PCAOB as they conduct their post-implementation review of the new audit reporting standard
Understanding sentiment toward racial unrest through temporal and geographic lenses: a multilevel-analysis across metropolitan areas in the United States
No full textRacial unrest has long been a salient social issue in the United States. Time and space provide essential contexts for the emergence and evolution of racial unrest. However, the relationships between these contextual factors and public responses to racial unrest remain insufficiently explored. This study seeks to fill that gap, blending geocoded, time-stamped racial unrest tweet data with census information. It aims to explore how temporal elements and geographical characteristics of metropolitan areas contribute to the emergence of negative sentiment reactions to racial unrest on social media platforms. The racially charged unrest that transpired in Ferguson, Missouri in 2014 serves as our case study. We select 33 metropolitan regions across the U.S. for our analysis. Our findings indicate that temporal processes, encompassing circadian rhythms, weekday-weekend variations, and temporal decay, correlate with expressions of anxiety and anger, albeit not sadness. Furthermore, our analysis reveals geographical characteristics-notably income inequality and segregation, combined with the number of Black victims-to be associated with manifestations of anxiety
Breaking the Silence: Unveiling the World of Sex Trafficking in the Lone Star State
No full textIn this project, I delve into the complex and often misunderstood world of sex trafficking within the Texas Triangle. Through meticulous research and firsthand accounts from law enforcement, this story challenges prevalent myths and misconceptions surrounding the issue. By debunking common narratives, I hope to shed light on the true nature of sex trafficking and its distinctive features within this region.
The Texas Triangle, comprising Houston, Dallas-Fort Worth, and San Antonio, presents a unique landscape for trafficking operations, shaped by a convergence of demographic, economic, and geographic factors. Through an exploration of these dynamics, I uncover the mechanisms through which trafficking manifests in the area, revealing a stark differentiation from societal misconceptions.
Through various examples and insights, I present the intricate workings of sex trafficking, dispelling prevalent misconceptions about its methods and scope. Central to my narrative is of the distinction between sensationalized portrayals and the harsh realities faced by victims of trafficking. From the exploitation of vulnerable individuals to the complicity of trafficking tactics, I confront the realities of this crime in a raw, authentic way. By amplifying voices and challenging prevailing narratives, I emphasize the urgency of understanding and addressing this multifaceted issue.
Ultimately, "Breaking the Silence" serves as a poignant call to action, compelling readers to confront the uncomfortable truths of sex trafficking in the Texas Triangle and beyond. Through knowledge and awareness, we empower ourselves to combat exploitation and advocate for justice in our communities
The Effects of AI Generated Marketing Content on Consumer Sentiments and Purchase Decisions
No full textGenerative Artificial Intelligence (Gen AI) has garnered significant attention across academic, business, and mainstream spheres due to its ability to simulate human intelligence and perform intellectual activities often more efficiently than humans. This paper synthesizes literature on Gen AI, particularly on its applications in digital marketing, focusing on its implications for content creation. To further examine the uses of Gen AI in digital marketing, this paper explores the effectiveness of Gen AI in creating marketing content, as well as its impact on consumer trust, brand authenticity, and consumer purchase decisions. Following preliminary research, a study was conducted among TCU Neeley School of Business students ages 18 to 26, representative of Generation Z consumers, to garner insights into their ability to differentiate between AI-generated and human-made marketing content. Findings suggest that while most Generation Z consumers can discern AI-generated content, their trust in products/brands and purchase decisions remains largely unaffected by the knowledge that content is AI-generated. Because of these findings this paper suggests that marketers can leverage AI-generated content among Generation Z consumers without significantly impacting consumer trust and perceptions of brand authenticity. However, the study highlights the importance of transparency and ethical considerations in AI-driven marketing to uphold consumer trust and loyalty. Overall, this research contributes to the understanding of Generative AI's role in digital marketing and underscores the importance of responsible and transparent AI use in shaping consumer experiences and perceptions
Zinc oxide nanoparticles mediate bacterial toxicity in Mueller-Hinton broth via zn2+
No full textZinc oxide nanoparticles (ZnO NPs) are promising antimicrobial agents due to their broad-spectrum antibacterial activity and low production cost. Despite many studies demonstrating the effectiveness of ZnO NPs, the antibacterial mechanism is still unknown. Previous work has implicated the role of reactive oxygen species, physical damage of the cell envelope, and/or release of toxic Zn2+ ions as possible mechanisms of action. Assays utilizing S. aureus mutant strains ¿katA and ¿mprF demonstrated that hydrogen peroxide and electrostatic interactions are not crucial for mediating ZnO NP toxicity. Instead, we find Zn2+ accumulation mediates toxicity independent of physical contact. Through this, we conclude that soluble Zn2+ is the primary mechanism by which ZnO NPs mediate toxicity in Mueller-Hinton Broth. Future work investigating the effect of ZnO NP synthesis methods on Zn2+ dissolution could allow for the synthesis of ZnO NPs that possess chemical and morphological properties best suited for antibacterial efficacy
Problematic social media use and vaping among Mexican-American college students
No full textIntroduction: Social media use and vaping nicotine are highly prevalent in the daily lives of young adults, especially among Mexican-American college students. The excessive and compulsive use of social media platforms, coupled with the urge to stay continuously connected, can lead to problematic social media use. To date, no studies have explored the impact of problematic social media use on the daily patterns of vaping among this vulnerable population. Methods: In Spring 2023, we employed Ecological Momentary Assessment over a period of 14 days to collect real-time daily data on participants� social media use and vaping behaviors via a mobile phone�based application. Participants were 51 Mexican-American college students aged 18�25 years, 72.5% female, who were current vapers. We used generalized linear regression models to examine differences in vaping behaviors among participants with and without problematic social media use. All regression models adjusted for age, sex, and SES. Results: Participants with problematic social media use vaped on an average of 5.9 days compared to 5.7 days reported by those without problematic social media use (p?<?.05). Problematic social media use is associated with more frequent daily vaping [b?=?0.03; 95% CI: 0.02�0.05], increased number of days vaping [b?=?0.14; 95% CI: 0.07�0.20], and vaping higher nicotine concentrations [b?=?0.08; 95% CI: 0.03�0.14]. Conclusion: Results suggest that problematic social media use significantly increases the risk of daily vaping among Mexican-American college students. Findings highlight the need to strengthen digital resilience and social media literacy to help college students navigate and mitigate the risks of social media