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Media’s New-Age Opinion Leaders: Audience Perceptions of SMI Credibility and Opinion Leadership Role
No full textWith worldwide technological and communication advancements in the last few decades, everyday citizens can capture, create, and share news through social media platforms. Nowadays, prominent social media influencers (SMIs) influence where and from whom online audiences consume their news and information. This study aims to explore how different SMI attributes – such as attractiveness, expertise, and trustworthiness – and their social media tactics create or add to audience perceptions of SMIs as credible online opinion leaders. Applying Two-Step Flow theory and Source Credibility theory, the study used data from a survey of 115 participants to understand how audiences perceived the trustworthiness and expertise of SMIs when evaluating credibility. The research found that SMI trustworthiness and expertise have stronger positive relationships with credibility, and SMI attractiveness has the strongest positive relationship with opinion leadership. Yet, the regressions show that SMI trustworthiness has a statistically significant effect on opinion leadership, and both attractiveness and trustworthiness have a statistically significant effect on credibility. This study integrates and provides an examination of modern mass media communications and audience perceptions of SMI credibility and the opinion leadership role. The findings suggest that social media users prioritize attractiveness and trustworthiness when considering SMIs to be credible opinion leaders, while content attractiveness and expertise play minor, insignificant roles
An Integrated Skeletal Muscle Methylome-transcriptome Profile in Pre-clinical Colorectal Cancer Cachexia Models and Chemotherapy Aggravating the Effects of Cachexia
No full textCancer cachexia is a wasting syndrome characterized by the loss of skeletal muscle affecting cancer patients’ independence and quality of life. Cancer cachexia affects up to 80% of cancer patients and is responsible for 30-40% of cancer-related deaths. Previous studies have demonstrated sex-specific differences in the onset and progression of cancer cachexia; however, these differences remain underexplored. To date, pharmacological and nutritional interventions are largely ineffective in preventing or reversing cachexia. Chemotherapy, a first-line cancer treatment, is known to trigger cachexia by itself complicating prognosis and therapy response. In addition, epigenetic alterations, such as DNA methylation (DNAm), are known to impact other types of muscle atrophy but remain unexplored in the context of cancer cachexia. Therefore, this dissertation aimed to investigate DNA methylation (DNAm) patterns during the onset, progression, and severity of colorectal cancer cachexia across biological sexes (Aim 1, Chapter 3), and to define how chemotherapeutic treatments interact with cancer to influence muscle atrophy in a sex-specific manner (Aim 2, Chapter 4). To achieve Aim 1, I employed a novel experimental design including: (1) effective chemotherapy (tumor reduction), (2) ineffective chemotherapy (no change in tumor size), and (3) chemotherapy- only, non-cancerous control groups, allowing for the evaluation of cachexia driven by cancer, chemotherapy, or both. I found that while chemotherapy and cancer induce similar phenotypic effects in males, chemotherapy in females exacerbates multi-organ alterations. In addition, my findings suggest muscle wasting in chemotherapy-treated mice may occur through mechanisms distinct from those driven by cancer alone, potentially involving DEPTOR dysregulation. For Aim 2, I utilized transcriptomic and methylomic data, and their integration, from two colorectal cancer cachexia models of varying severity. By analyzing multiple time points, I characterized the molecular progression of cachexia and identified sex-specific differences. Notably, I found that early methylome dysregulation was associated with impaired signaling associated with muscle regeneration and activation of neurodegenerative pathways in both sexes. Overall, this dissertation advances our understanding of the molecular mechanisms underlying muscle wasting during cancer cachexia onset and progression. It also highlights the distinct pathways activated by chemotherapeutic agents in males and females and their differences, underscoring the importance of including female population in cachexia research and for sex- specific preventive and therapeutic strategies
The Cannon-Thurston Map for Relatively Hyperbolic Free-by-Cyclic Groups
No full textLet F = H1 ∗ · · · ∗ Hk ∗ Fr be a splitting of a finitely generated free group, H = {H1 , . . . , Hk } a set of subgroups of F , and Φ ∈ Aut(F ) an automorphism such that for any i, Φ([Hi ]) = [Hj ] for some j. Consider the free-by-cyclic group Gϕ = ⟨F, t | t−1 xt = Φ(x)⟩. Suppose Gϕ is strongly hyperbolic relative to H̃ = {H̃1 , . . . , H̃k }, where H̃i = ⟨Hi , t | t−1 xt = Φ(x)⟩. In this thesis, we prove the existence and some properties of the Cannon-Thurston map î : ∆(F, H) → ∆(Gϕ , H̃). We build on work of mathematicians studying Cannon-Thurston maps in the contexts of manifolds, hyperbolic group extensions, and hyperbolic free-by-cyclic groups, in particular Cannon and Thurston [CT07], Mj [Mit98], and Kapovich and Lustig [KL15]. Our goal is to consider this work in the context of relatively hyperbolic free-by-cyclic groups, in a similar sense as Pal [Pal10]. Pal proved the existence of the Cannon-Thurston map for certain extensions of relatively hyperbolic groups. We use a construction based on the Grushko trees of splittings, rather than coned-off Cayley graphs, to look at the geometry of relatively hyperbolic free-by-cyclic groups and to prove the existence of the Cannon-Thurston map î. Using this construction, we are able to very quickly observe that î is surjective, and, in a particular case, that the restriction î |∂T : ∂T → ∆Gϕ is surjective as well. We also show that a known theorem about the Cannon-Thurston map for hyperbolic free-by-cyclic groups does not hold in the relative case
Moral Worth and Motivational Demands
No full textIt has become a philosophical commonplace to distinguish actions that are merely right from actions that possess moral worth. To be right, an action needs only to accord with the demands of morality. To possess moral worth, an action needs not only to be right, but to be non-accidentally so. While this much is uncontroversial, what is involved in this sense of non-accidentality is a matter of ongoing debate. This thesis lies at the heart of that debate. Many parties to this debate agree that actions with moral worth must be properly motivated. Suppose someone speaks respectfully to a colleague only to serve their professional interests. Had their interests been served by doing something disrespectful, they would have gladly done so. Given their motives, it was only accidental that they did the right thing. Throughout this thesis, I focus on what sort of motives render actions relevantly non-accidental. After defining key terms in the introduction, I devote the second chapter duty-based views. According to these views, an action has moral worth if and only if the agent who performs it is motivated by the fact that it is right. This view enjoys an advantage regarding reliability: if I am motivated by rightness itself, this motive will never lead me to act wrongly. But this view makes moral worth too hard to come by for agents with imperfect moral understanding, and it leads us to deem praiseworthy some actions that do not reflect well on their performers. Thus, duty-based views are extensionally inadequate. Chapter three concerns feature-based views. On these views, an action has moral worth if and only if the agent is motivated by the feature(s) that make the action right. These views direct our attention toward morally important features and make moral worth obtainable for people who are mistaken about whether their actions are right. But without certain specifications, these views cannot secure the reliability an account of moral worth needs. Even well-placed concerns can come in the wrong degree, leading to wrongful actions. Therefore, some actions motivated by relevant right-making features are only accidentally right. In chapter four, I present my own care-based view: an action has moral worth if and only if the agent is motivated by an appropriate distribution of care among all their action’s morally relevant features, while being independently praiseworthy. This view inherits the best parts of other views. It ensures reliability by requiring motives to be appropriate in content and degree, and it still requires attention to what is morally important. It also makes moral worth obtainable for those with mistaken moral beliefs. Avoiding accidental rightness matters because we often care not only what people do, but what they would do in different situations. By centering what agents care about, my view classifies as morally worthy only those actions stemming from an appropriately deep commitment to what matters. This is no accident
Predicting Case Clearance for Victims of Anti-Transgender Homicide in the United States
No full textThere is a shortage of research exploring case clearance of anti-transgender bias homicides. This study will comparatively examine the similarities and differences in anti-transgender bias homicide cases with and without arrests at the victim, situational and incident levels occurring in the United States between 2013 and 2023. Data are extracted from the Bias Homicide Database (BHDB), the National Coalition of Anti-Violence Programs (NCAVP), and the Human Rights Campaign (HRC). This project will address the gap in understanding case clearance of anti-transgender bias homicides, provide policy implications, and ideas to further the discipline’s understanding of the topic. Keywords: LGBTQIA+ victims, bias homicide, transgender, victimizatio
Measuring the Impact of GED Preparation on GED Testing Outcomes
No full textThis quantitative study investigates the relationship between participation in GED preparation programs and GED test outcomes among adult learners at a single Adult Basic Education (ABE) center located in an urban area of a south-central U.S. state. Recognizing the significance of the GED as an alternative credential to a traditional high school diploma, the research examines how instructional hours and structured preparation correlate with students’ final scores in mathematics, English language arts, social studies, and science. The study also describes the demographic characteristics of the learners, including gender, race, and age groups, and analyzes their performance on the Test of Adult Basic Education (TABE) pre- and post-tests. By focusing on academic achievement within a defined educational setting, this research aims to provide actionable insights for educators and policymakers seeking to enhance the effectiveness of GED preparation efforts. The study is framed within the broader context of challenges faced by individuals without a high school diploma, including limited employment opportunities and poorer socioeconomic outcomes. While the research emphasizes measurable academic variables, it acknowledges limitations related to its single-site design and the exclusion of qualitative factors such as student motivation and external life circumstances. Despite these constraints, the findings are expected to offer valuable contributions to understanding how GED preparation programs impact adult learners’ success on high-stakes equivalency tests. Ultimately, this study seeks to inform instructional practices and program development in adult education, supporting efforts to improve GED attainment for non-traditional learners
Navigating Stigma and Privacy: Health-Related Communication Among Bangladeshi Women
No full textWomen in Bangladesh often silently bear the burden of stigma tied to their bodies, minds, and societal roles. This study examines the coping strategies women use to manage health-related stigma and their privacy while facing issues like reproductive health, mental health, and postpartum challenges. The study was conducted by utilizing in-depth interviews with 17 Bangladeshi women. Stigma Management Communication Theory (SMC) and Communication Privacy Management Theory (CPM) are the two frameworks that guided the study. The findings of the study reveal that stigma often silences women and threatens their social identities, and women feel that having a health problem means they have failed in some way. Therefore, strategies such as, avoiding conversations, distancing themselves from stigma, concealing their struggles, and relying on their own resilience were adopted by women. On the other hand, privacy, closely connected to their stigmatized identity, becomes an emotional labor. The process of choosing people to share private information is not straightforward. It is a risky decision influenced by trust, social judgment, and the need to maintain dignity. This study highlights women\u27s voices and adds to health, stigma, and privacy research in the Global South. It shows how communication can support or challenge stigma
Small Angle X-ray Scattering Studies of Collagenase H Mutant, ColH-E416Q
No full textCollagenase H (ColH) from Hathewaya histolytica plays a central role in collagen degradation through endopeptidase and carboxytripeptidase reactions. To better understand how its domain architecture supports these functions, we examined the solution structure of a catalytically inactive mutant, ColH-E416Q, using small-angle X-ray scattering (SAXS). The E416Q mutant is catalytically inactive because the glutamate residue at position 416, which normally functions as a general acid/base during catalysis, is replaced by glutamine—an amide that cannot donate or accept protons effectively, thus disabling the proton transfer steps essential for peptide bond hydrolysis. SAXS results indicate that the E416Q substitution leaves overall domain architecture and conformational behavior intact with comparative differences in dynamics. The E416Q mutation in ColH selectively abolishes catalytic activity while preserving substrate binding, making it a valuable tool for structural and mechanistic studies. By stabilizing enzyme–substrate complexes that would otherwise be transient, ColH-E416Q offers a strategic platform for capturing intermediate snapshots of collagen unwinding and cleavage. This presents a potential avenue for the development of novel collagenase inhibitors that target non-catalytic sites; an approach of particular interest given the close resemblance between bacterial catalytic sites and those of human matrix metalloproteases (MMPs), a similarity that made earlier inhibitor designs unsuitable due to anticipated side effects. These findings deepen our mechanistic understanding of bacterial collagenolysis and provide a structural basis for developing next-generation inhibitors or engineered collagenase variants with improved specificity
Effect of Dietary Tryptophan Supplementation and Heat Stress on Pasture Broiler Welfare and Performance
No full textPasture-raised broiler chickens face temperature extremes that can threaten welfare. In the study, we evaluated whether a 0.26 % tryptophan-supplemented diet (T) improved heat stress (HS) resilience in Ross-708 broilers raised on pasture. At D14, birds began the T or remained on the control diet (C) and were moved outdoors. On D20 and 41, half of each group underwent six-hour HS; the remainder stayed under thermoneutral (TN) conditions. Weekly body weight, feed intake on D20 and D41 were recorded, and fear was measured using the Tonic Immobility (TI) test. Neither diet nor HS affected body weight. However, tryptophan supplementation resulted in higher feed conversion ratios (FCR) in Week 6 and cumulatively from D14 to 42 compared to C, suggesting reduced feed efficiency. On D20 and 41, HS significantly reduced feed intake during HS, regardless of diet. At both ages, HS did not significantly affect fear behavior, though HS birds numerically remained immobile longer on D22, suggesting increased fearfulness. On D15, C birds showed shorter latency to first head movement compared to T birds, indicating heightened vigilance; these effects did not persist following HS on D22. Under HS, birds spent more time sitting, panting, and wing spreading, and less time standing and eating compared to TN. Within HS pens, T birds exhibited more simultaneous panting and wing spreading (PAWS) than controls, implying greater thermal stress. Age affected thermoregulatory behavior during HS, where younger birds on D20 were more active and utilized convective cooling (walking, wing spreading, PAWS), whereas older birds on D41 relied more on evaporative cooling behaviors, including panting and sitting behaviors. Overall, tryptophan supplementation did not positively affect growth performance or reduce fear before or after HS; instead, it may have exacerbated thermal stress
Effect of Marination and Storage Time on The Properties and Meat Quality of Broiler Breast
No full textAbstract The poultry industry has implemented numerous methods, as marination and aging, to improve meat quality and satisfy consumer demands. Three experiments were developed to assess the effects of vacuum tumble marination and aging on the proteins of chicken breast. These experiments utilized 0.75 % sodium chloride, 0.45 % phosphate, and water in a marinade. In experiment one, 270 fillets were allocated into six treatment groups, each comprising 45 fillets. Six days of storage time were used, marinating and storing the fillets in each group at a temperature of 4°C. Following each day of storage period, the fillets underwent a 15-minute marinade utilizing the vacuum tumble method, followed by an additional 24-hour storage period prior to analysis. The texture, drip loss %, marination pick-up %, purge %, and cook loss % were significant parameters assessed using a texture analyzer. In the second experiment, fillets were marinated and stored for 2, 4, or 6 days of storage at 4C and compared to fillets that were non-marinated and stored for the same periods, over three replications. Changes in pH, color, and the identical meat quality parameters as the initial experiment were assessed. This facilitated the evaluation of the marinade\u27s effects during different storage durations. In the third experiment, marinated chicken breasts with spaghetti meat myopathy were compared with neither marinated nor non-marinated fillets. As in previous experiments, thirty affected breasts were marinated utilizing the identical method and marinade. The assessment centered on the following parameters: pH, color before to and after to marination, drip loss %, pick-up %, purge %, cook loss %, and texture. In experiment one, the drip loss % tended to increase as storage time passed, whereas the purge percentage decreased. Cook loss % also increased throughout the six days of storage, indicating that meat quality deteriorated with time. The texture analysis revealed marginal variations throughout the days, with no discernible patterns. Overall, non- marinated fillets exhibited a greater loss in the second experiment compared to their marinated counterparts. Although the initial pH values of the fillets did not differ significantly, they exhibited a higher pH level after marinating. The color analysis results conducted before and after marination indicated that marinated fillets exhibited marginally reduced initial L* and b* values, but substantial variations after marination, which indicated enhanced color retention. Overall, non-marinated fillets suffered the greatest loss in the third experiment, in comparison to fillets treated with spaghetti meat myopathy and conventional marinated fillets. The marinated fillets exhibited higher pH post-marination, suggesting enhanced pH stability. There were notable variations in color values following marination, whereby marinated fillets exhibited superior color retention on average. In general, the outcomes of these experiments demonstrate that vacuum tumble marination is an efficacious method for enhancing the consistency of color, pH stability, and water retention of poultry meat, which are critical determinants of meat quality. Aging and marination are crucial processes in preserving and improving meat quality throughout the storage period. Key Words: marination, breast, quality, storage, color, pH