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Illiquidity Contagion and Pricing of Commonality Risk: Evidence From a Dynamic Conditional Correlation Model
No full textThis paper investigates the pricing of the commonality in liquidity risk in the U.S. stock market by using a more comprehensive measure of market illiquidity cost that can reflect the liquidity condition of broader asset markets, and by forming portfolios in a way that is consistent with the definition of the commonality risk. Estimating a conditional version of the Liquidity-Adjusted Capital Asset Pricing Model by the Dynamic Conditional Correlation approach, we find a commonality risk premium that is higher than those derived from alternative measures. The premium is time varying, with values being higher during periods of market turmoil
Semisynthetic Derivatives of the Verticillin Class of Natural Products through Acylation of the C11 Hydroxy Group
No full textThe verticillins, a class of epipolythiodioxopiperazine alkaloids (ETPs) first described 50 years ago with the discovery of verticillin A (1), have gained attention due to their potent activity against cancer cells, noted both in vitro and in vivo. In this study, the complex scaffold afforded through optimized fermentation was used as a feedstock for semisynthetic efforts designed to explore the reactivity of the C11 and C11′ hydroxy substituents. Functionality introduced at these positions would be expected to impact not only the potency but also the pharmacokinetic properties of the resulting compound. With this in mind, verticillin H (2) was used as a starting material to generate nine semisynthetic analogues (4-12) containing a variety of ester, carbonate, carbamate, and sulfonate moieties. Likewise, verticillin A succinate (13) was synthesized from 1 to demonstrate the successful application of this strategy to other ETPs. The synthesized compounds and their corresponding starting materials (i.e., 1 and 2) were screened for activity against a panel of melanoma, breast, and ovarian cancer cell lines: MDA-MB-435, MDA-MB-231, and OVCAR3. All analogues retained IC50 values in the nanomolar range, comparable to, and in some cases more potent than, the parent compounds
Influence of DRD4 Receptor Gene Polymorphism on Aspirational Quality and Approach Motivation
Get PDFThe present study investigates the presence of a molecular genetic basis of the quality of aspiration and motivation for behavior described by Ryan and Deci’s self-determination theory and Gray’s biopsychological theory of personality respectively. In this study, investigation was carried out to determine the impact of DRD4 receptor gene polymorphism on intrinsic and extrinsic aspiration as well as approach motivation using the Aspiration Index scales and Behavioral Inhibition and Activation (BIS/BAS) scales as our psychometric instrument of evaluation. In a pilot study consisting of 9 healthy subjects, the 7R allele of DRD4 receptor gene was associated with higher mean score of extrinsic motivation. Furthermore, the 7R allele of the DRD4 gene had a higher mean value for the relative centrality of extrinsic motivation in the aspiration index of participants. The findings of this study suggest that the presence of certain allelic expressions of DRD4 receptor gene may predict aspirational quality. However, a full study comprising a large sample of participants is required to establish the accuracy our hypothesis
Policies and Practices Regarding Transgender Students According to Arkansas School Administrators
Get PDFArkansas schools have received changing and conflicting guidance for accommodating transgender students, and policies and practices within schools can critically impact this population. This mixed-methods, exploratory study investigated what official policies and unofficial but established practices exist in Arkansas high schools regarding transgender students’ use of preferred names and pronouns as well as their access to sex-separated facilities and activities. The study also examined the frequency of such policies and practices within various school demographic categories including school size, community type, socioeconomic status, and geographic location. The researcher analyzed survey results from 55 secondary principals in Arkansas. Few schools had formal policies regarding transgender students in the aforementioned areas. In established but unofficial practice, the use of students’ preferred names and gender was more common in the classroom than on official records. For sex-separated facilities, schools often provided a private or unisex option or required students to use the restrooms corresponding to their sex on official records. Regarding sex-separated activities, schools generally decided on a case-by-case basis instead of an established procedure. Over a third of principals did not report having a transgender student within the past three years, and a chi-square test showed none of the four demographic variables appear to affect the frequencies or types of policies and procedures regarding transgender students. In a qualitative analysis of the open-response questions, three themes arose: the importance of respecting student needs, the favored flexibility in not having a formal policy, and the mixed reactions from varied stakeholders. Recommendations for practice and future research are included
Sonata for clarinet and piano / Francis Poulenc
No full texthttps://orc.library.atu.edu/atu_vhs004_1/1007/thumbnail.jp
The Role of uspE in Virulence and Biofilm Formation by Histophilus somni
No full textUspE is a global regulator in Escherichia coli. To study the function of Histophilus somni uspE, strain 2336::TnuspE was identified from a bank of mutants generated with EZ::Tn5™[KAN-2] Tnp Transposome™ that were biofilm deficient. The 2336::TnuspE mutant was highly attenuated in mice, the electrophoretic profile of its lipooligosaccharide (LOS) indicated the LOS was truncated, and the mutant was significantly more serum-sensitive compared to the wildtype strain. In addition to forming a deficient biofilm, exopolysaccharide (EPS) production was also compromised, but the electrophoretic profile of outer membrane proteins was not altered. RNA sequence analysis revealed that the transcription levels of some stress response chaperones, transport proteins, and a large number of ribosomal protein genes in 2336::TnuspE were significantly differentially regulated compared to strain 2336. Therefore, uspE may differentially function in direct and indirect expression of H. somni genes, but its attenuation may be linked to poor biofilm formation and rapid clearance of the bacteria resulting from a compromised LOS structure. Our results support that uspE is a global stress regulatory gene in H. somni
The Drosophila melanogaster Neprilysin Nepl15 is Involved in Lipid and Carbohydrate Storage
Get PDFThe prototypical M13 peptidase, human Neprilysin, functions as a transmembrane “ectoenzyme” that cleaves neuropeptides that regulate e.g. glucose metabolism, and has been linked to type 2 diabetes. The M13 family has undergone a remarkable, and conserved, expansion in the Drosophila genus. Here, we describe the function of Drosophila melanogaster Neprilysin-like 15 (Nepl15). Nepl15 is likely to be a secreted protein, rather than a transmembrane protein. Nepl15 has changes in critical catalytic residues that are conserved across the Drosophila genus and likely renders the Nepl15 protein catalytically inactive. Nevertheless, a knockout of the Nepl15 gene reveals a reduction in triglyceride and glycogen storage, with the effects likely occurring during the larval feeding period. Conversely, flies overexpressing Nepl15 store more triglycerides and glycogen. Protein modeling suggests that Nepl15 is able to bind and sequester peptide targets of catalytically active Drosophila M13 family members, peptides that are conserved in humans and Drosophila, potentially providing a novel mechanism for regulating the activity of neuropeptides in the context of lipid and carbohydrate homeostasis
Reduced Toxicity of Centruroides vittatus (Say, 1821) May Result from Lowered Sodium β Toxin Gene Expression and Toxin Protein Production
Get PDFBody tissue and venom glands from an eastern population of the scorpion Centruroides vittatus (Say, 1821) were homogenized and molecular constituents removed to characterize putative sodium β toxin gene diversity, RT-qPCR, transcriptomic, and proteomic variation. We cloned sodium β toxins from genomic DNA, conducted RT-qPCR experiments with seven sodium β toxin variants, performed venom gland tissue RNA-seq, and isolated venom proteins for mass spectrophotometry. We identified greater than 70 putative novel sodium β toxin genes, 111 toxin gene transcripts, 24 different toxin proteins, and quantified sodium β toxin gene expression variation among individuals and between sexes. Our analyses contribute to the growing evidence that venom toxicity among scorpion taxa and their populations may be associated with toxin gene diversity, specific toxin transcripts variation, and subsequent protein production. Here, slight transcript variation among toxin gene variants may contribute to the major toxin protein variation in individual scorpion venom composition
Effects of Various Training Techniques on Bat Velocity of High School Baseball Players
Get PDFFaster bat speed allows a baseball or softball player more time to decide how to hit the ball and provides more transfer of momentum to the ball (Nathan, 2003; Syzmanski, DeRenne, Spaniol, 2009). Purpose: This paper examines the effectiveness of three training strategies for improving bat speed among high school baseball players. Methods: Nine high school students were recruited and separated into 3 groups using different training implements. A standard bat (29 oz.), a weighted bat (45 oz.), and Therabands attached to a standard bat were used over a 3-week training program. Data were analyzed using a Kruskal-Wallis ANOVA. Results: The standard bat group experienced no change in bat speed (± 0.89), while the weighted bat group increased by 1.9 ± 0.46 mph and the Theraband group improved by 3.1 ± 0.38 mph. The only significant difference was in the change in bat speed between the Theraband group and the standard bat group (p = .022). All other data were non-significant. Conclusions: Attaching Therabands to a standard bat may be an effective training tool to improve bat speed