The Fourth Generation t-prime in Extensions of the Standard Model

We study the effects of a fourth generation t' quark in various extensions of the standard model. In the Randall-Sundrum model, the decay t'--> t Z has a large branching ratio that could be detected at the Large Hadron Collider (LHC). We also look at the two-Higgs doublet models I, II and III, and note that, in the latter, the branching ratio of t' --> t H, where H is a Higgs scalar or pseudoscalar, is huge and we discuss detection at the LHC. A few comments about the minimal supersymmetric standard model are also included.Comment: 4 pages, 2 figures. Version to be published in Phys. Rev.

Palimpsest

Palimpsest explores the various ways in which the models, individuals who have gained and/or lost a large amount of weight, feel empowered and vulnerable. The skin is marked and each discoloration or indentation telling a story of loss, gain, and removal. The photographs mark these changes

Measuring Lead Concentrations of Vacant Lots in the Tree Street Neighborhood of Lewiston, ME

High levels of lead contamination have detrimental health implications for communities, with the most profound impacts of lead poisoning affecting young children. The City of Lewiston, Maine, is home to a disproportionate amount of reported lead poisoning cases as compared to the rest of the state. Within Lewiston, the downtown “Tree Street” neighborhood contains 72% of all reported lead-poisoning cases in the city, signifying a need to identify the source(s) of lead exposure and minimize the impact of lead contamination on Tree Street residents. In collaboration with Healthy Neighborhoods, we identified 19 vacant lots in the Tree Street neighborhood to test for soil lead contamination. With the aim of quantifying and contextualizing the distribution of lead across the vacant lots, we took 9 composite samples from each lot and tested them for lead using an X-Ray Fluorescence (XRF) gun. The XRF gun provided an elemental analysis of each sample in parts per million (ppm). Using this data, we created maps showing the geographic distribution of lead across the neighborhood and each site. We also created graphs showing the concentration distribution across and within sites. The most concerning site (site 17) had an average lead concentration of 634 ppm and a maximum value of 2370 ppm, which surpasses the Environmental Protection Agency (EPA) safety threshold of 400ppm for bare soil in play areas. Along with identifying the extent and distribution of lead contamination in the vacant lots, we considered which types of lead remediation are best suitable for minimizing exposure to lead contamination in the Tree Street neighborhood. In this report, we examine the remediation strategies of phytoremediation, soil caps and raised beds, and soil amendments. After a comprehensive discussion of these three strategies in relation to the criteria of cost, feasibility, and effectiveness, we determine which strategies are most suitable for use in the lead-contaminated Tree Street neighborhood vacant lots. We recommend the use of sunflower phytoremediation as our primary remediation technique. We also recommend the use of certain soil amendments as a secondary remediation technique; the use of this strategy, however, is contingent on whether Healthy Neighborhoods and the City of Lewiston have access to the appropriate equipment necessary for the processing of these amendments. Finally, we end our report with recommendations for next steps for Healthy Neighborhoods and the City of Lewiston in continuing the project of creating a lead-free community

Factors Affecting Pharmacokinetic Variability of Imatinib Mesylate (Gleevec, STI-571)

Imatinib mesylate, the first tyrosine kinase inhibitor to gain approval by the FDA, remains as a pivotal example of rational drug design. Initially, imatinib was found to target the bcr-abl fusion protein in CML and further targets have subsequently been identified, including c-kit in GIST. Though a great number of studies have elucidated underlying mechanisms to explain emerging resistance to this anti-cancer agent, many cases of resistance remain unexplained. Furthermore, patients exhibit high interindividual variability in imatinib pharmacokinetics, which may contribute to suboptimal drug exposure and response

CWA In-Lieu Fee Mitigation: Project and Programmatic Risks

In 2008, after prompting by the U.S. Congress, the U.S. Environmental Protection Agency (EPA) and the U.S. Army Corps of Engineers (the Corps) issued a regulation governing compensatory mitigation under the Clean Water Act (CWA). The agencies' primary goal was to improve the effectiveness of mitigation projects to offset the impacts of filling wetlands and streams. The 2008 Compensatory Mitigation Rule was also designed to level the playing field for the three types of mitigation providers: mitigation banks, in-lieu fee (ILF) programs, and permittee-responsible mitigation. After a decade of experience with this regulation, it is appropriate to reflect on its implementation. Although much has been written about mitigation banks, less attention (in the literature at least) has been paid to ILF programs and permittee-responsible mitigation.5 This Comment focuses on ILF programs

Influence of the dual ABCB1 and ABCG2 inhibitor tariquidar on the disposition of oral imatinib in mice

<p>Abstract</p> <p>Background</p> <p>Imatinib, a tyrosine kinase inhibitor currently approved for treatment of several malignancies, has been shown to be a substrate for multiple efflux-transporter proteins, including ABCB1 (P-glycoprotein) and ABCG2 (BCRP). The effect of inhibiting these transporters on tissue exposure to imatinib remains unclear.</p> <p>Objective</p> <p>To assess the role of these transporters on drug disposition, 50 mg/kg imatinib was administered to Balb/C mice, 30 minutes after receiving tariquidar (10 mg/kg), an inhibitor of both ABCB1 and ABCG2, or vehicle, via oral gavage.</p> <p>Methods</p> <p>Quantitative determination of imatinib in mouse plasma, liver and brain was performed using a newly-developed and validated liquid-chromatography-mass spectrometric method. Results: Exposure to imatinib was 2.2-fold higher in plasma, liver and brain in mice that received tariquidar, as compared to those that received the vehicle (P = 0.001). The peak plasma concentration did not increase substantially, suggesting that tariquidar is affecting the distribution, metabolism and/or excretion of imatinib, rather than absorption. Though tariquidar increased the absolute exposure of imatinib, the brain-to-plasma ratio of imatinib was unaffected.</p> <p>Conclusion</p> <p>This study suggests that intentional inhibition of ABCB1 and ABCG2 function at the blood-brain barrier is unlikely to significantly improve clinical outcome of imatinib with currently used dosing regimens.</p

The Grizzly, September 21, 2023

Rush Week 2023 • Sudoku • Fall Student Engagement Events • More IIE Events This Semester • Prints and Imprints Left Behind - at the Berman • Student Responses to Changes to Good Samaritan Policy • Have You Ever Played Rugby? • Ursinus Introduces Temporary Expansion to the Wellness Center: The Hive (A Thread)https://digitalcommons.ursinus.edu/grizzlynews/2015/thumbnail.jp