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Social Support of First-Generation College Applicants During the Transition to College Onboarding Phase: A Mixed Methods Sequential Explanatory Case Study
No full textThis mixed methods case study sought to explain first-generation college applicant melt with respect to support provided through a digital onboarding platform at State University. Data were analyzed to understand use of the platform for social support purposes, resulting in a predictive model that demonstrated social support was a greater predictor of melt among first-generation college applicants than both distance from home and adjusted gross income. Additionally, staff were interviewed regarding support practices and platform usage. Three key findings emerged: the onboarding platform did not provide adequate support to applicants; enrollment management staff scrambled to compensate for this support gap; and ultimately, this resulted in untrackable and potentially inequitable support practices. The findings demonstrated that support has a positive relationship with melt reduction, but support practices and technology use alignment is required to ensure systematic, equitable, and effective support distribution
REPAIR AND SURFACE FUNCTIONALIZATION OF FIBER REINFORCED POLYMER COMPOSITES BY COLD SPRAY
No full textFiber-reinforced polymer composites are widely used in industries and applications such as energy, automotive, defense, and aerospace. This study investigates the application of polymer cold spray, an emerging additive manufacturing process, for coating and repair of fiber-reinforced polymer (FRP) composites. The research starts with feasibility studies focused on the cold spray deposition of thermoplastic nylon-6 particles on woven glass fiber-reinforced composites (GFRP). A parametric study determines critical process parameters window, ensuring successful deposition and bonding without compromising the macroscale mechanical behavior. These findings indicate that the cold spray process does not adversely affect the fiber integrity or surface quality of the composites. Advancing from coating to repair, we explore polymer cold spray as a rapid method to repair and restore the mechanical properties of damaged GFRP composites. We assess the effect of impact energy on mechanical properties of GFRP panels and use a variety of powder materials for repair, including thermoplastics, thermosetting materials, and novel fiber-reinforced composite powders. Notably, when the damage was confined to the surface and near-surface levels, repairs by fiber-reinforced thermoset powder feedstock exhibits superior mechanical performance and improved recovery. This finding underscores the potential of fiber-reinforced thermoset powders in enhancing the durability and longevity for repairing the damaged composite materials
MATRIX PROCESSING WITH PHOTONIC ANALOG COMPUTING
Get PDFIn the digital age, a wide variety of engineering problems have been solved, to a great deal of success, by digital computing techniques. The flexibility of software and relatively low cost of digital computing hardware make it an ideal starting point for solving a majority of tasks, and the numerical stability of software solutions make it highly appealing as the major workhorse for computational tasks. Despite this, many problems are actually suboptimally solved by digital methods, leading to systems with high latency, low throughput, power hungry parallel processing units and an excess of memory for discretizing sensor inputs. Computational photonic circuits are an emerging field of study which holds a number of advantages over modern digital computations. Their high bandwidth allows for the implementation of operations from basic arithmetic to frequency domain manipulation at speeds and efficiencies that their electrical counterparts are unable to approach, while still consuming less power per operation. This high bandwidth also enables parallelized computations in the same waveguide through the use of Wavelength-Division Multiplexing. Their analog nature allows for signal processing in continuous time, and eliminates the cost, memory requirements and precision loss resulting from the need to digitize massive amounts of data. This thesis will examine applications in which these circuits can provide a more optimal solution to tasks traditionally handled by software, and propose circuit architectures and control techniques that facilitate these more optimal solutions
A Homogeneous Time-Resolved Fluorescence Screen to Identify SIRT2 Deacetylase and Defatty-Acylase Inhibitors
Get PDFHuman sirtuin-2 (SIRT2) has emerged as an attractive drug target for a variety of diseases. The enzyme is a deacylase that can remove chemically different acyl modifications from protein lysine residues. Here, we developed a high-throughput screen based on a homogeneous time-resolved fluorescence (HTRF) binding assay to identify inhibitors of SIRT2\u27s demyristoylase activity, which is uncommon among many ligands that only affect its deacetylase activity. From a test screen of 9600 compounds, we identified a small molecule that inhibited SIRT2\u27s deacetylase activity (IC50 = 7 μM) as well as its demyristoylase activity (IC50 = 37 μM). The inhibitor was composed of two small fragments that independently inhibited SIRT2: a halogenated phenol fragment inhibited its deacetylase activity, and a tricyclic thiazolobenzimidazole fragment inhibited its demyristoylase activity. The high-throughput screen also detected multiple deacetylase-specific SIRT2 inhibitors
Deep retinal layer microvasculature alterations in schizophrenia
Get PDFA subset of individuals with schizophrenia (SZ) are thought to have a microvascular component to their illness with studies demonstrating alterations in retinal superficial, deep, and choroidal microvasculature networks. However, the direction and location of these alterations have differed across studies. In a recent study, we reported that individuals with SZ demonstrated lower superficial layer perfusion density than a healthy control (HC) group. The current study investigated characteristics of the deep vascular layer in SZ. We included 28 individuals with a diagnosis of SZ or schizoaffective disorder, and 37 HCs. Optical coherence tomography angiography (OCTA) data was collected to measure deep retinal layer perfusion density, skeletonized vessel density, vessel diameter index, and fractal dimension. We conducted between-group comparisons to examine differences in these OCTA variables between SZ and HC groups. A trend analysis was conducted to determine if differences reflected a linear trend according to age and illness length, and Spearman correlations were conducted to determine associations between deep and superficial layer density. Individuals with SZ demonstrated significantly lower bilateral perfusion density and vessel diameter index, as well as lower left eye skeletonized vessel density and fractal dimension. There was a significant linear trend in the data indicating that individuals with chronic SZ demonstrated the lowest OCTA values, followed by individuals within two years of their first episode of psychosis who did not differ from older controls, followed by younger controls, who demonstrated the highest values in at least one eye. Lower density values in the deep retinal layer were also significantly associated with lower density values in the superficial layer. Overall, results suggest that microvascular alterations are present in multiple retinal layers in SZ and that they may be useful visual system biomarkers of neurovascular changes in the disorder
A Case of Esophagogastric Junction Outflow Obstruction Resulting to Megaesophagus in a 37-Year-Old Male
Get PDFEsophagogastric junction outflow obstruction (EGJOO) is a major motility disorder characterized by an increase of \u3e 15 mmHg in the integrated relaxation pressure (IRP) with or without problems in esophageal motility. This presents as dysphagia, chest pain, regurgitation, heartburn, cough, and a globus sensation, with dysphagia. Severe cases may lead to a megaesophagus causing compression of mediastinal structures.6 Its similarity to other esophageal disorders urge an investigation to improve its identification and treatment. This report presents a case of EGJOO in a 37-year-old cachectic male patient with dysphagia and vomiting, eventually determined to be EGJOO with diagnostic manometry
A Preliminary Report on the Role of Lipoxin A4 in Reinstating the Blood-Brain Barrier Integrity in a Rodent Model of Acute Inflammation with Impaired Cerebrovasculature
Get PDFBackground: The blood-brain barrier (BBB) is responsible for maintaining brain homeostasis and ultimately proper neuronal function. Disruption of the BBB, leading to increased BBB permeability, has been reported in several neurodegenerative diseases, including Alzheimer’s disease (AD) and traumatic brain injury (TBI). Lipoxins (LXs) are a class of arachidonate-derived eicosanoids, which are a class of specialized pro-resolving lipid mediators (SPMs). SPMs are known to inhibit immune response through inhibition of cellular infiltration, downregulation of pro-inflammatory mediators and upregulation of anti-inflammatory mediators. Hence, LXs are recognized as “breaking signals” in the inflammatory process. One form of LXs, Lipoxin A4 (LXA4), has been found to decreased production of proinflammatory mediators, inhibit neutrophils chemotaxis and infiltration to the site of injury, and promote the phagocytic clearance of debris by macrophages. Therefore, LXA4 serves a critical role in resolution of inflammatory process by regulating the activation of monocytes and modulating the generation of reactive oxygen species (ROS).
Hypothesis: LXA4 treatment reinstates the BBB integrity in a rodent model of acute BBB breakdown and inflammation.
Methods: Nine-month-old female Sprague Dawley rats were given an intravenous (IV) injection of 15 mg/kg lipopolysaccharide (LPS) through the tail for inducing acute inflammation and BBB breach. After three hours, the rats were injected with 9 µg/kg LXA4 or Saline (Vehicle control). Four treatment groups were thus developed: LPS only, LPS/LXA4, LXA4 only, and Saline only. Animals were euthanized at 24 hours of LPS treatment and brain samples were processed for paraffin-embedded sections and immunohistochemistry. Sections comprising of hippocampus and cortical regions were selected for detection of impaired BBB as demonstrated by the extravasation of immunoglobulin G (IgG) and IBA1 (microgliosis marker). The area of the cerebral cortex and number of cortical blood vessels presenting with IgG extravasation were estimated and compared between treatment groups. Similarly, IBA1 immunoreactivity was quantified using Color Deconvolution V9 tool of Aperio ImageScope (Leica BIOSYSTEMS).
Results: LXA4 treatment following LPS injection demonstrated decrease in the extent of IgG leak compared to LPS only group. Likewise, we observed significant decrease in microgliosis in LPS-LXA4 group compared to LPS only.
Conclusion: These preliminary results demonstrate potential beneficial effects of LXA4 in reinstating BBB integrity and reducing neuroinflammation in rat model of acute BBB breach and inflammation
Advancing Risk Stratification in HFpEF: Unveiling the Potential of Cardiac Fibrosis Markers for Early Diagnosis and Enhanced Patient Outcomes
Get PDFHeart failure with preserved ejection fraction (HFpEF) challenges clinicians due to its diverse presentation and limitations in traditional diagnostic criteria. This study delves into the potential of cardiac fibrosis markers like galectin-3, NT-proBNP, and trimethylamine N-oxide (TMAO) to enhance diagnostic precision and patient outcomes in HFpEF. A systematic review of sixteen relevant studies revealed that these biomarkers offer promise for early detection and improved risk assessment. For instance, TMAO indicates systemic implications of HFpEF, while galectin-3 shows predictive value across heart failure types. Additionally, machine-learning models incorporating multiple biomarkers predict significant risk of adverse outcomes. Despite these advances, challenges like biomarker standardization and validation persist, highlighting the need for comprehensive risk assessment strategies. This study underscores the importance of these markers in addressing critical gaps in HFpEF care and calls for their integration into routine clinical practice
Walking the Walk: Searches that Demonstrate Commitment to an Inclusive, Diverse, and Equitable Library Workplace
Get PDFBenchmarking executive compensations: exploring fresh perspectives on chief executive officer (CEO) compensation drivers in major US corporations
No full textPurpose
This study aims to contribute to the ongoing assessment of executive compensation by investigating the nexus between managerial entrenchment factors, adopting a multifaceted perspective encompassing both economic and non-economic dimensions. Design/methodology/approach
This research employs pooled cross-sectional Ordinary Least Squares (OLS) regression and Least Squares with Dummy Variables (LSDV) models with fixed effects to examine the determinants of Chief Executive Officer (CEO) compensation. Findings
This research identifies firm size, performance (via ROA and Tobin’s Q), and CEO characteristics (age, tenure, stock ownership, MBA degree) as significant determinants of executive compensation at the 0.05 level. In contrast, the prestige of educational institutions, doctoral degrees, and the MBA’s relevance to short-term performance, along with CEO tenure, do not significantly affect pay. Additionally, the study highlights the significance of industry type (manufacturing vs technology) in shaping compensation, emphasizing the role of firm metrics and CEO credentials in designing executive pay packages. Originality/value
This research introduces an innovative approach to controlling unobserved heterogeneity and adjusting for the dynamic nature of CEO compensation attributes across diverse CEO characteristics. By integrating both pooled Ordinary Least Squares (OLS) and Least Squares Dummy Variable (LSDV) models, the study addresses the challenges posed by time-invariant variables and unobservable heterogeneity. Such issues have historically skewed the accuracy of traditional OLS models in identifying the comprehensive array of factors—both economic and non-economic—that influence CEO compensation. This novel methodological framework significantly advances the examination of unobservable variables that may vary not only across the firms selected for analysis but also over time periods, thereby offering a more detailed understanding of the determinants of CEO pay