Purification of a Bacteriophage Protein Involved in Host Range Specificity

The Escherichia coli ferric hydroxamate uptake receptor FhuA serves as the receptor for ferrichrome-Fe(III) complexes, with TonB protein energizing the active transport of the complex. The FhuA receptor is exploited by a variety of bacteriophages as a conduit into the cell. Interestingly, certain of these phages carry a gene called “Cor”, the product of which, when cloned and expressed from a plasmid, blocks transport by FhuA. In the present study, components of the cor gene from the bacteriophage ϕ80 were used to construct an IPTG-inducible MalE-Cor-His6 fusion protein, which allowed for affinity purification of the Cor protein. At 61 residues in length, purified Cor protein was not readily demonstrable by standard SDS polyacrylamide gel electrophoresis. The purification of Cor protein via maltose-binding and nickel exchange chromatography as well as visualization of Cor protein by silver staining of samples resolved on Tricine-SDS polyacrylamide gels is described

Investigating the Student Enrollment Decision at WKU

The purpose of this research is to investigate the relationships between the enrollment decision of first-time, first-year students admitted to Western Kentucky University and the amount of financial aid awarded, as well as demographic information. The Division of Enrollment Management provided a SAS dataset containing various information about all WKU students admitted in 2013, 2014, and 2015. Additionally, information about the 2016 class of admitted students was provided. The data has been analyzed in SAS Enterprise Miner. We performed analysis using decision tree modeling and logistic regression modeling. Results of these two procedures indicated the importance of credit hours earned by students before attending WKU, the student’s academic performance in high school, and the financial aid package offered to the student by the University

European Union Latin American and Caribbean Relations: Mercosur and the state of inter-regionalism in Latin America & the Caribbean

Studies of EU foreign policy have identified the use and support for regionalism as a method of interest promotion and normative diffusion to form and characterize economic and political partnerships around the world. While the actual impact of constructivist political influence in Latin America remains a contested subject, these theories have been used to evaluate the functions and purposes of the many different regionalist political and economic bodies developed there since the 1960s. Latin American regional relations are currently in a state of dissolution and reformation into newer formats with the recent reinvigoration of the EU-Mercosur relationship with the 2019 EU-Mercosur Association Agreement representing only one example. This partnership is the key point of contact for EU-LAC relations and the preeminent example of EU-modeled regionalism in the world today. Using the literature of EU normative regionalism, I will describe the histories, ideologies, and interests of the key regional bodies of the Latin American and Caribbean region and evaluate the influence and performance of the EU, focusing on that between the EU and Common Market of the South, or Mercosur, as the deepest and most valuable to the praxis of inter-regionalism as a key element of EU foreign relations. I apply the analytical framework of EU activity developed by Dr. Arantza Gomez Arana and draw on published material from the EU Commission, statistical evaluations from the Organization for Economic Cooperation and Development (OECD), and public news sources as well as academic journals to evaluate the EU’s strategic approach and identify the stances and potential impacts of the 2019 Association Agreement.Master of Art

Globalization: A Veto Player Perspective

Different countries have varying levels of globalization. Many features, such as size, play a part in determining the level of globalization in countries. I argue that globalization is influenced by veto players in systematically different ways. To understand these different relationships, globalization must be broken apart into three dimensions (political, economic, and social). Political globalization is negatively affected by veto players. Economic globalization is not affected by veto players directly but is influenced by related phenomena. Social globalization is positively affected by veto players. To test my arguments, I employ a Time Series Cross Section (TSCS) method to analyze a data set covering 33 countries from 1970 to 2015. I find that as expected, each dimension of globalization has a fundamentally different relationship with veto players. My findings contribute to the growing understanding that globalization is more complex than previously thought. I link my findings to disagreements in the existing literature on globalization and show that some of this disagreement may have been due to failure to take the complexity of globalization into account

Late-Stage Functionalization of 1,2-Dihydro-1,2-Azaborines

Thesis advisor: Shih-Yuan LiuDescribed herein are two distinct research projects focused on the development of metal-catalyzed late-stage functionalization strategies for 1,2-dihydro-1,2-azaborines separated into three chapters. The first chapter discusses the development, synthesis, and recent contributions to the field of azaborine chemistry. The second chapter details the development of rhodium catalyzed B-H bond activation for the synthesis of a new class of BN-stilbenes as well as the discovery of a novel B-H to B-Cl transformation that is successful both with B-H azaborines as well as other B-H containing compounds. The third chapter pertains to the development of a B-H and B-Cl tolerant C(3) functionalization strategy through the use of Negishi cross-coupling. Using this methodology, previously unreported isomers of BN-naphthalene and BN-indenyl have been synthesized and characterized.Thesis (PhD) — Boston College, 2015.Submitted to: Boston College. Graduate School of Arts and Sciences.Discipline: Chemistry

Electric Propulsion of a Different Class: The Challenges of Testing for MegaWatt Missions

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/97101/1/AIAA2012-3942.pd

Microwave dielectric study of spin-Peierls and charge ordering transitions in (TMTTF)2_2PF6_6 salts

We report a study of the 16.5 GHz dielectric function of hydrogenated and deuterated organic salts (TMTTF)$_2$PF$_6$. The temperature behavior of the dielectric function is consistent with short-range polar order whose relaxation time decreases rapidly below the charge ordering temperature. If this transition has more a relaxor character in the hydrogenated salt, charge ordering is strengthened in the deuterated one where the transition temperature has increased by more than thirty percent. Anomalies in the dielectric function are also observed in the spin-Peierls ground state revealing some intricate lattice effects in a temperature range where both phases coexist. The variation of the spin-Peierls ordering temperature under magnetic field appears to follow a mean-field prediction despite the presence of spin-Peierls fluctuations over a very wide temperature range in the charge ordered state of these salts.Comment: 7 pages, 6 figure

Mode Transitions in Hall Effect Thrusters

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106480/1/AIAA2013-4116.pd

Hyperparathyroidism, platelet intracellular free calcium and hypertension in chronic renal failure

Hyperparathyroidism, platelet intracellular free calcium and hypertension in chronic renal failure. To investigate possible relationships between hyperparathyroidism, alterations in intracellular free calcium concentration ([Ca2+]i and hypertension in chronic renal failure, serum concentrations of intact parathyroid hormone (PTH) were measured by two-site immunometric assay, and platelet ([Ca2+]i) was assessed using the fluorescent indicator fura-2. Thirty-six patients with chronic renal failure were studied, 10 with normal serum PTH concentrations (mean 8.0 ± 0.6 pmol/liter), 17 with elevated serum PTH (35.0 ± 7.2 pmol/liter) and 9 patients with elevated PTH (36.2 ±5.9 pmol/liter) who were receiving nifedipine. Platelet [Ca2+]i was increased in patients with elevated PTH, compared with those in whom PTH was normal (138 ± 16 vs. 83 ± 7 nmol/liter, P < 0.01). A linear relation was observed between serum PTH and platelet [Ca2+]i in these patients (r = 0.818, P < 0.001). In contrast, platelet [Ca2+]i was not elevated (84 ± 9 nmol/liter) in the patients with elevated PTH who were receiving nifedipine. A linear relation was also present between both serum PTH (r = 0.616, P < 0.001) and platelet [Ca2+]i (r = 0.576, P < 0.005) and mean blood pressure. Nine patients with hyperparathyroidism were restudied after treatment with the vitamin D analogue alfacalcidol. This resulted in significant decreases in serum PTH (P < 0.01), platelet [Ca2+]i (P < 0.02), and mean blood pressure (P < 0.05). These studies indicate that [Ca2+]i may be increased early in renal failure, and that this increase occurs in association with both hyperparathyroidism and hypertension. Furthermore, treatment of hyperparathyroidism with alfacalcidol may result in reductions in both [Ca2+]i and blood pressure. The lack of elevation in [Ca2+]i in nifedipine-treated patients with hyperparathyroidism suggests that, in uremia, increases in cytosolic calcium induced by PTH or other factors may be mediated in part by dihydropyridine-sensitive mechanisms