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Variation in Stress Response Regulation Across Natural Isolates of \u3ci\u3eSaccharomyces cerevisiae\u3c/i\u3e
Get PDFThe stress response of Saccharomyces cerevisiae is a valuable area of study for understanding cellular adaptation mechanisms that govern survival in fluctuating environments. This dissertation investigates stress response regulation in yeast through the roles of Hog1 mitogen-activated protein kinase (MAPK) and the post-transcriptional regulator Mkt1, a key post-transcriptional regulator, in diverse wild yeast isolates. Hog1 is traditionally known for its central role in osmotic stress regulation in the high-osmolarity glycerol (HOG) pathway. This study expands the functional scope of Hog1 to include oxidative and ethanol-induced stress responses.
In parallel, we investigate post-transcriptional regulation of stress responses by the Mkt1 interactome, linking Mkt1 to metabolic and translational regulation. Using SILAC-based proteomics, we outline the dynamic nature of the Mkt1 interactome.
We further address the pitfalls of ribonucleoprotein complex procedures in RNA-protein interaction studies, proposing enhanced protocols for more comprehensive investigations into stress-induced gene regulation.
Collectively, this dissertation offers new knowledge on the complexity of stress adaptation in S. cerevisiae, and the importance of strain-specific variation within stress response pathways, demonstrating the value of studying natural variation in molecular studies. The work not only advances the understanding of Hog1 and Mkt1 in stress regulation but also gives an overall perspective of how natural genetic variation influences cellular responses to environmental stress
Bacterial Chondronecrosis with Osteomyelitis in Broilers: Etiology and Selected Mitigation Measures
Get PDFBacterial chondronecrosis with osteomyelitis (BCO) is the predominant cause of lameness in broiler chickens. It mainly impacts broiler production and animal welfare, causing substantial financial losses accounting for 1- 2% due to bird condemnations at the marketing age. Remediating BCO lameness disease demands investigating its causes using appropriate models and evaluating preventive measures, such as enhancing epithelial tissue health and tight junction integrity in the digestive and respiratory tract, strengthening immune functions, and improving bone strength. Therefore, the objectives of this dissertation were to 1) study predisposing factors for BCO lameness by investigating the effects of deoxynivalenol (DON) and fumonisin (FUM) mycotoxins contamination on BCO lameness by exposing broilers reared on wire (W) and litter flooring (L) to diets contaminated with mycotoxins (MTX), 2) determine the efficacy of adding different combinations of 1,25-Dihydroxyvitamin D3-glycoside (G-1,25(OH)2D3) and phytogenic antioxidants on improving bone and gut health and the immune system 3) investigate the optimal timing for adding Availa® ZMC to broiler diets to mitigate BCO lameness, reduce feed additive costs, and effectively protect against BCO lameness. As a result, the findings in this dissertation include three main significant areas. First, increasing the incidence of BCO lameness using mycotoxins due to increasing intestinal permeability supports a correlation between intestinal barrier integrity and BCO lameness and suggests that DON and FUM mycotoxins are predisposing factors for increasing BCO. Second, no significant difference in protection against BCO when supplementing 1.0 µg G-1,25(OH)2D3 individually or in conjunction with polyherbal mixtures or Thyme oil. In addition, increasing the G-1,25(OH)2D3 dosage from 1.0 µg/kg to 10 µg/kg did not yield a lower lameness incidence beyond the low dosage. Finally, incorporating 0.15% Availa® ZMC supplementation into the broiler diet during the initial 28 days is considered ideal for the 0.15% Availa® ZMC dose compared to adding 0.15% Availa® ZMC for the entire production cycle. In conclusion, this collection of studies provides valuable insights into understanding the etiology of BCO lameness and finding possible ways to prevent and remediate its occurrences
Nonparametric Methods for Bayesian Community Detection in Complex Networks
Get PDFNetwork analysis is becoming an increasingly popular interdisciplinary area of study, with emerging interest in fields like sociology, biology, economics, and ecology. Within the niche of network analysis, capturing the community structure of a network is one important achievement that many statisticians have been working toward over recent decades. The most popular modeling technique for latent community detection is the Stochastic Block Model (SBM), which falls into the category of latent variable models and will serve as the baseline model throughout this thesis. SBM is widely regarded as the most effective community detection method as it detects latent community membership among individuals in a network, and the probability that two individuals have a relationship is based only on community structure. Though effective, SBM has significant limitations. Along with other traditional latent variable models, SBM requires a pre-specified number of communities. The community structure, which would lend access to the number of groups, is often unknown in application. Furthermore, traditional SBMs are often insufficient in modeling networks with block structures that do not have well-separated communities or low within-group probabilities. Due to these limitations, recent developments of SBMs have included extensions of the traditional SBM to the infinite parameter space. The partition structure of the network is then modeled using nonparametric Bayesian methods. In this thesis, I will explore three nonparametric Bayesian methods for community detection in the context of SBM, including the Dirichlet Process, the Gnedin Process, and a Mixture of Finite Mixtures approach. I aim to provide supporting evidence through model comparison that nonparametric methods outperform traditional community detection methods among networks with complex structures and an unknown number of communities
The Rhetorical Use of the Lower Classes in Three Primary Accounts of the First Crusade
Get PDFThis study analyzes the rhetorical use of the lower classes in three primary accounts of the First Crusade: Albert of Aachen, the Gesta Francorum, and Raymond of Aguilers — specifically with an eye towards the proper maintenance of the order of society through everyone performing their assigned role. Through a close reading of these three texts this study demonstrates how the three authors engage with and uphold versions of the idealized three orders model of medieval society. Though there is nuance between each source, broadly, each of the authors presents the lower classes as a force that needs to be guided by the clergy and controlled by the nobility. When the three orders model is upheld, society functions smoothly to the benefit of all, including the lower classes themselves
We\u27re in it Together: The Influence of Social Connection on Distress Tolerance
Get PDFMany factors are associated with heightened psychopathology, including difficulties tolerating distress and having low social support. Emotional support has been argued as the most vital facet to the construct of social support. Through emotional support, people can feel more connected to another person and thus feel more cared for and valued. It is important to understand whether interpersonal closeness can cause increased momentary distress tolerance. The current study (n = 165) involved an experimental manipulation of perceived interpersonal closeness, where participants experienced either induction of perceived interpersonal closeness, a control condition, or an interpersonal disconnection induction. Interpersonal closeness was manipulated by having the participant engage in a conversation with a confederate which evoked emotional intimacy. The confederate followed a script that invoked either a friendly (interpersonal closeness) or unfriendly (interpersonal disconnection) perception from the participant. The control condition involved no interaction with the confederate except for being in the same room. Distress tolerance was then measured with the Emotional Image Task (EIT) which involves viewing emotionally evocative images and measuring both how long people view the image until they experience distress and how long they can tolerate that distress. Results did not find a direct influence of manipulated interpersonal closeness on distress tolerance measures; however it was found that various trait- level measures like agreeableness, extraversion, anxiety, depression, and stress related to differences in distress tolerance. Further research is needed to clarify the link between social support and distress tolerance, as the current study does not experimentally confirm previously found correlations
Eating What They Kill: The Stark Reality of Athlete Compensation in Mixed Martial Arts and Potential Solutions
Get PDF“They eat what they kill.” Dana White, President of the Ultimate Fighting Championship (“UFC”) said this about the state of fighter pay in the organization. White, the voice of the company, holds firm that fighters are adequately compensated for their services. The reality is that UFC fighters are not paid what they deserve, and, one way or another, there are big changes coming to the organization and the sport of Mixed Martial Arts (“MMA”) as a whole. In this Comment, I will discuss how the UFC has used its market power to suppress fighters’ wages and subject fighters to inequitable contract provisions. Further, I will argue that major changes are coming to the MMA industry and explore the UFC’s options in facilitating those changes. Finally, I will propose that a UFC fighter’s union is the best way to resolve the organization’s current mistreatment of their own athletes while still protecting the interests of the fans and the UFC itself. In Part I, I will discuss the origins of the UFC and its rise to market dominance in the MMA industry, and I will explain how the modern UFC’s status in the sport creates legal issues for the company. In Part II, I will discuss the two primary potential solutions to the UFC’s current legal issues and evaluate each of those solutions from the perspective of the UFC, the fighters, and the fans
Decriminalizing Disease: A Health Justice Approach to Infectious Diseases and Criminal Law
Get PDFInfectious diseases, also called communicable diseases, are largely a public health issue and should not be criminalized. This Article seeks to re-frame the discussion around the legal framework for infectious diseases in a way that moves beyond a punishment mindset and toward a health justice mindset. The focus in this Article is on health justice rather than traditional understandings of public health, defined as the science and practice of improving the health of people and their communities. The Article makes three novel contributions. First, it applies a health justice framework to the critique of infectious disease criminalization. Second, the Article assesses the implications of recent efforts to repeal or reform laws criminalizing HIV. Third, this Article examines the criminalization of infectious diseases other than HIV, in particular, hepatitis and COVID-19. Part I discusses the history of the criminalization of HIV through the lens of health justice. Part II provides an overview of current laws enabling HIV criminalization (in the following referred to as HIV criminalization laws) and describes the use of these laws in recent years. Part III considers how criminal laws have been applied to infectious diseases such as viral hepatitis and COVID-19 and explores the ramifications of these applications. The Article concludes with some takeaway lessons for public health and criminal law
