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THE ROLE OF EMOTION IN HELP-SEEKING BEHAVIORS AMONG FIRST GENERATION COLLEGE STUDENTS
No full textAccess to information and support is widely understood as critical for shaping one's opportunities in life. However, the role of emotion in determining how individuals seek information and support, particularly in unfamiliar environments, is often overlooked. Drawing from 68 interviews with first generation college students who were situated in a more diverse environment, had less financial burden and were more likely to live at home, I investigate how these first-generation college students gain the information and support they are said to be missing to navigate the challenges of post-secondary institutions. I find that this sample of first generation college students often felt a lack of understanding from their parents, who failed to empathize with the challenges of college life, such as workload stress and navigating the grading system. As a result, despite discussing their school experiences with their parents, these conversations often remained limited, superficial and selective. In efforts to rectify some of the missing information they lacked, I discovered that these first-generation college students adopted varied help-seeking strategies, shaping how they sought information and support during college. Some employed a proactive community engagement approach, actively seeking assistance from their communities. In contrast, over half relied on a solo strategy, refraining from seeking external support. Those who embraced self-reliance often equated it with academic excellence. These strategies were related to how students discussed school-related stress. Further, I find that these students rely on knowledge and empathy when determining who to seek help from in college. I introduce a framework of four different categories of individuals from whom these first generation college students might seek information and support from. While students engage with individuals from all categories, many offered limited assistance. The most valuable were the empathic experts, highly knowledgeable and empathetic individuals. Students sought them out because of their ability to relate to them and provide holistic support. However, the effectiveness of students' efforts remains unclear. Together, these findings challenge ideas about how people find information and support in new contexts and the importance of emotion in the process of social mobility
OUT OF CONTROL: AN HISTORICAL ANALYSIS ON THE SOVIET AFGHANISTAN WAR
Get PDFIn the past 5 years, the geopolitical landscape has dramatically changed. While America withdrew from Afghanistan, Russia began it’s “Special Military Operation” to annex Ukraine. Decades of peace in Europe disintegrated, NATO left with a refugee crisis and the United States began to fund Ukraine with financial aid and advance military equipment. However, a massive disinformation campaign began to turn the general public against Ukraine. As this special military operation advances to its second year, Ukrainian forces have reclaimed most of its lost territory and uncovered a significant amount of war crimes perpetrated by Russian conscripts.
This thesis attempts to provide a historical analysis of Russia’s previous campaign to subjugate Afghanistan and to provide the reader a deeper understanding of war in a tactical, strategic and operational setting. This thesis contributes to the discussion of unconventional warfare, counterinsurgency, air power and realist theory and how all topics intersect
Measurement and Correction of Aberrations Observed by an Optical Window at Extreme Temperatures in the Infrared Regime
No full textOptical windows are the eyes of Electro Optical and Infrared (EO/IR) and Radio Frequency (RF) sensors, but under thermal stresses material changes in the optical windows introduce undesired optical aberrations that degrade sensor performance. These aberrations translate into boresight errors and left uncorrected will negatively impact the angle accuracy of a sensor system, and drive the guidance, navigation, and control (GNC) of an autonomous-flight system unstable. Boresight error correction techniques are critical, and required to maintain GNC stability. A unique compensation technique using in-situ measurements was developed based on simulated boresight error for uniform and non- uniform thermal loads. Developed techniques are based on the accuracy of in-situ measurements and therefore assume an anti-reflection coating on the inner surface of the optical window to remove surface reflections. Several anti-reflection coatings were designed, prototyped and experimentally tested up to temperatures of 1400° C. These coatings were developed via oblique angle deposition and allowed to overcome limitation in the availability of transparent materials suitable in the IR. The development of a high temperature coatings for the infrared regime is an essential part to compensation techniques and a critical contribution to other applications like solar cells
Towards Chronic Inflammatory Control Through VNS: Development Of Mechanically Biocompatible Neuromodulation Devices
Get PDFThe field of neuromodulation has identified vagus nerve stimulation (VNS) as a possible treatment for inflammatory diseases ranging from depression to inflammatory bowel disease. Despite the widespread interest, no one has shown modulation of inflammatory cytokines with a fully chronically implanted, electrical VNS device in a rodent model. In an attempt to address this, fellow researchers and I investigated temporal interference stimulation (TIS) as a potential solution, and ultimately determined that its mechanism of action is different than what has been described previously in literature. I then developed a neuromodulation system utilizing a fully passive, wirelessly driven, implantable neurostimulator, small enough to exist solely on the rat vagus nerve. The stimulator contains a novel, bidirectional current limiting circuit to protect tissue from excessive stimulation. This system was tested through sciatic nerve stimulation, to demonstrate its functionality and versatility, and VNS, to demonstrate its chronic reliability and inflammatory control, in Long Evans rats. After three weeks of implantation, the devices were able to significantly modulate blood pressure as well as increase and decrease the concentrations of anti-inflammatory and pro-inflammatory cytokines, respectively, after injection of lipopolysaccharides. To further improve efficacy, I designed an application specific integrated circuit (ASIC) using a flexible amorphous indium gallium zinc oxide thin film transistor process to address the drawbacks of the passive stimulator. I then tested these ASICs on the benchtop and demonstrated their efficacy in animal experiments through sciatic nerve stimulation and vagus nerve stimulation. Miniaturized, flexible neuromodulation tools may open the door to future chronic VNS studies in animal models and their translation to humans
STUDIES OF DEEP HOMOLOGY AND PHENOTYPIC EVOLUTION UNDER A PHYLOGENETIC FRAMEWORK
Get PDFPhylogenies provide a logical framework for generating evolutionary hypotheses to explain observed biological patterns, but less effort is put into inferring the phylogenies themselves. Modern phylogenetics has focused on molecular data due to their abundance, but morphological data remain critical for uncovering and understanding the deep history of life. Fundamental differences in the two major types of phylogenetic data mean that adoption of molecular phylogenetic methods in analyzing morphology requires more than mere data replacement.
In this dissertation, I examine the expansion of the mitogen-activated protein kinase (MAPK) signaling network through comprehensive phylogenetic analyses across Eukarya. Results reveal two major pulses of network expansion along the human evolutionary backbone. I find that the two groups of mitogen-activated protein kinase kinase kinase (MAP3K) played different roles in the evolution of the network—sterile (STE) MAP3K likely represents the original MAP3K, whereas tyrosine-like (TKL) MAP3K was key to function expansion.
Given the irreplaceable role of fossils in inferring the past, I focus next on a new Mesozoic stem therian that includes a three-dimensionally preserved femur associated with cranial material. Besides a phylogenetic reconstruction that places this specimen within Triconodontidae, I generate linear models for body mass prediction using various dentoskeletal measurements and find not only that joint dimensions provide surprisingly precise predictions, but also that previous predicted Eutriconodont body masses are probably inflated.
Finally, I describe and examine a problem in model-based phylogenetics that I term state space misspecification (SSM), where the modeled state space of a character is different from the true state space. My simulations reveal a complex behavior of SSM, wherein the impact notably depends on state space size difference, mutation rate, and the misspecified proportion of characters.
With this dissertation, I aim to 1) demonstrate the importance of an explicit phylogenetic framework in evolutionary questions and 2) contribute to the improvement of morphological phylogenetic methods. Despite a wide spectrum of topics, they collectively represent an exploration of the application of phylogenetics, as well as the refinement of that application
Identifying biomarkers and developing outcome measures for clinical trials in Kabuki syndrome
Get PDFKabuki syndrome (KS) is a Mendelian disorder of the epigenetic machinery caused by pathogenic variants in KMT2D, causing KS1, or KDM6A, causing KS2. Individuals with KS typically present with intellectual disability, characteristic facial features, and growth abnormalities. A mouse model of KS1 was found to have deficits localized to the hippocampus, including impaired neurogenesis and hippocampal memory defects. As expected since KS is caused by variants in genes that maintain chromatin accessibility, treating the KS1 mice with interventions that promote open chromatin rescued these neurological deficits postnatally. Before these therapies can be translated to clinic, it is important to establish biomarkers and outcome measures specific to KS to have quantifiable ways to test improvement in clinically relevant areas. To do this, we first performed deep phenotyping and found that adults with KS often present with anxiety, whereas children with KS more frequently present with executive dysfunction. Future clinical trials for KS designed across age groups can use measures targeting these areas. Additionally, we found that KS1 mice and a subset of individuals with KS1 present with sensorineural hearing loss, which contradicts current clinical dogma that the hearing loss in KS is primarily conductive. This finding can be informative to clinicians caring for these patients. We investigated long-term potentiation (LTP) in KS1 mice and found that they have increased early-phase LTP and decreased late-phase LTP, with sex driving this difference. Then to translate this into a KS-specific biomarker, we created a novel auditory EEG paradigm to try to approximate LTP in humans and found that there are differences in N1 amplitude by variant type in KMT2D, however, establishing differences between cases and controls needs further investigation in a larger cohort. Lastly, we investigated if the distinct DNA methylation (DNAm) pattern seen in KS can be changed with intervention. In our pilot clinical trial of a diet to treat KS, we found clear separation between treated and untreated samples, which makes DNAm a promising biomarker in KS. Overall, this work has established novel phenotypes and potential biomarkers which is important for both optimal patient care and future clinical trial design
Responses to respiratory virus infection and immunization
No full textRespiratory viruses lead to millions of cases of illness and thousands of admissions to hospitals and fatalities annually, such as measles and SARS-CoV-2. The fundamental preventive measures to reduce the risk of respiratory viruses is immunization, which helps people defend themselves from viruses and severe illnesses. However, safe and effective vaccines for respiratory viruses are still a major challenge to public health. In 2023, the United States reported approximately 900,000 hospital admissions for COVID-19 and 58 measles cases. The measles virus triggers immune suppression, leading to secondary infections like pneumonia and diarrhea, by depleting memory B and T cells. Individuals infected with SARS-CoV-2 may suffer long-term consequences, including Long COVID, a chronic condition that causes health problems that may require extensive care. The aim of this study is exploring the replication tropism of liveattenuated measles virus, evaluating the efficacy of a new measles vaccine, and the impact of convalescent plasma therapy on COVID-19 patients. These studies identified sites of LAMV replication in vivo and determined that a new recombinant measles vaccine could be a potential option for the immunocompromised group. After treatment with convalescence plasma, few COVID-specific antibody-secreting cells were found. The study is crucial in investigating and uncovering aspects of respiratory virus infections and immunization strategies, significantly contributing to public health knowledge and outcomes
MISBALANCE OF MEDULLARY RESPIRATORY CIRCUITS IMPLICATED IN DEATHS IN EPILEPSY
Get PDFObjective: Approximately 4,000 people die in the United States every year from Sudden Unexpected Death in Epilepsy (SUDEP). Data regarding SUDEP is difficult to gather as it is rare and often unobserved, but recent findings suggest a primarily respiratory collapse which occurs shortly after a seizure. This work explores mechanisms of respiratory drive that may underly these deaths.
Methods: My work has focused almost exclusively on the acute kainate model in urethane anesthetized rats in nonsurvival experiments. These animals will experience spontaneous sudden respiratory deaths in seizure either de novo or follow a respiratory stressor. Additional manipulations described in the text probe the underlying mechanisms of these deaths.
Results: Seizing animals experience de novo acid reflux due to ictal hypersecretion of stomach acid exacerbated by extreme aerophagia. Once acid reaches the larynx a laryngospasm triggers a strong central apnea which is highly fatal. Seizing animals also experience these fatal central apneas if a strong apnea is triggered via nasotrigeminal stimulation. Nonseizing animals always survive apnea trials, either laryngeal or nasotrigeminal. Carotid body drive is strongly implicated, with nonseizing carotid-body-deficient animals acquiring apnea-trial-mortality while upregulation of the carotid bodies lowers ictal mortality. The medullary convergence of the proposed apnea reflex circuits, the carotid body oxygen sensation circuits, and gasping drive in the ventral respiratory column suggest a core medullary circuit governing the competition of apnea and end-of-apnea gasping drive. These findings are further supported by human clinical observations. Direct recordings from the rodent medulla are also supportive.
Conclusions: The data suggest that seizure reduces the ability of the animal to produce effective gasping behaviors. Gasps are crucial to survival after an extreme apnea and to the restoration of the network to eupnea rhythms. The data are suggestive, but not conclusive, that the primary failure is a lack of end-of-apnea drive, rather than a hyperactivation of apnea. Circuit convergence in the central medulla, possibly the caudal solitary nucleus, is implied. If true, these findings strongly suggest that the risk of fatal post-obstructive-central apnea is measurable and gradually acquired
The Algebra of Categorical Spectra
Get PDFThis thesis develops fundamental theories of the algebra of categorical spectra. A categorical spectrum is a sequence of pointed -categories with identifications . After developing background materials on -categories and categorical spectra, we will define the tensor product of categorical spectra. This tensor product is analogous to the lax Gray tensor product of -categories, just as the tensor product of spectra is to the cartesian product of -groupoids. The tensor product will be applied to studying the stability of categorical spectra, i.e., the coincidence of certain finite weighted colimits and limits. This will further be applied to topological quantum field theories. In particular, we make precise Lurie's sketch of the deduction of the cobordism hypothesis with singularities from the plain cobordism hypothesis
Outward Protection from Face Masks: Insights from Reduced-Order Flow Models and Direct Numerical Simulations
Get PDFRespiratory diseases, such as influenza and COVID-19, which spread via pathogen-laden aerosols, have the potential to trigger global pandemics. Recent studies have shown that face mask usage among the public is an effective strategy to mitigate such airborne transmission. Proper usage of face masks, however, remains a challenge because of the complex underlying mechanisms of mask protection. Face masks can provide both inward and outward protection, and the current dissertation focuses on mask outward protection. A mask can filter the expelled aerosols and alter the exhaled airflow to provide outward protection. To study mask aerosol filtration, a reduced-order flow model of face masks is developed, which incorporates the peripheral leakage based on realistic gaps and the empirical data on filtration efficiency for various types of masks. Improvements in estimating the peripheral leakage are achieved by utilizing two-dimensional flow simulations to predict the pressure distribution inside a mask. The outward fitted filtration efficiency is employed to quantify the face mask effectiveness, and the results reveal that for typical masks like surgical masks, approximately 70\% of the exhaled aerosols can be filtered even with peripheral leakage accounting for 80\% or more of the total exhaled airflow. Moreover, by leveraging the insights from our model, transmission reduction of respiratory viruses within communities is explored, and we found that widespread mask adoption can effectively reduce the potential viral spread. The improved leakage estimation achieved by the two-dimensional simulations only leads to a minor increase in the mask performance because most aerosols do not adhere to the leaking flows but directly impact the mask. To study mask alteration of the exhaled airflow, three-dimensional flow simulations are performed with typical masks considering mouth and nostrils exhalation. An \textit{iblankFaster} algorithm is also developed to accelerate the immersed body determination in our in-house flow solver using the sharp-interface immersed boundary method. The temporally averaged flow fields from the three-dimensional simulations indicate that face masks can effectively reduce the strength and change the direction of the exhaled airflow, resulting in significantly shorter exhaled jet lengths. This further increases the outward protection afforded by face masks