Nuclearity and π-π Interaction Effects on Olefin Polymerization and Coordination Chemistry

This thesis details work performed on the use of secondary coordination sphere effects to impact olefin polymerization activity and tacticity control and the coordination chemistry of Y, Fe, and Cu. Chapter One provides a general introduction and summary of each chapter. Chapter Two describes work in collaboration with KFUPM on nuclearity effects in Zr bisamine bisphenolate complexes. Chapter Three describes the coordination chemistry of arene-appended Y di(pyridyl) pyrrolide complexes and the olefin polymerization activity of tris(dimethylamido) Ti, Zr, and Hf di(pyridyl) pyrrolide complexes. Appendix A describes the effects of bulky trialkylsilyl, triphenylsilyl, and diphenyl(alkyl)silyl substituents on the tacticity control of monozirconium amine bis(phenolate) complexes in 1-hexene polymerization. Appendix B describes the synthesis and structures of miscellaneous dizirconium amine bis(phenolate) complexes which could not be isolated in sufficient purity for olefin polymerization tests. Appendix C describes the synthesis, electrochemistry, and reduction of mesityl-substituted di(pyridyl) NHC supported Fe complexes. Appendix D describes the preparation, solid-state structures, and electrochemistry of di(pyridyl) pyrrolide and di(pyridyl) NHC Cu(I) and Cu(II) complexes displaying π-π interactions in the solid state. Appendix E describes work towards the synthesis of di(pyridyl) guanidinate proligands and metal complexes supported by di(pyridyl) urea, monopyridyl and di(pyridyl) N-heterocyclic olefin and N-heterocyclic vinylidene ligands for use in Lewis acid assisted olefin polymerization. Appendix F includes relevant spectra.</p

Economic Analysis of Atoxigenic Mitigation Methods for Aflatoxin in Corn in Central Texas

Atoxigenics and crop insurance are available to producers to assist in preventing economic loss from aflatoxin contamination in corn. Atoxigenics are a newer technology available to farmers, and although professional opinion of this biotechnology encourages its use, an economic analysis has not been performed to determine if the atoxigenics are overall economically beneficial to the producer when combined with crop insurance. The objective of this paper is to perform an economic analysis on the decision to use available atoxigenic treatments on a corn crop, and evaluate the economic outcome at different crop insurance levels for corn producers in Central Texas. This paper will use a risk based partial budget simulation model combined with an aflatoxin contamination simulation model to complete a risk analysis on the decision to use atoxigenic mitigation methods. Field level data on aflatoxin contamination levels is from Bell County, Texas. A representative farm was simulated with and without atoxigenic treatments and each case was simulated across a range of crop insurance options available to corn producers in Bell County. A total of 50 scenarios were simulated and compared based on net revenue. Results show atoxigenics do provide a monetary benefit to producers. When the atoxigenic treatment was compared to no atoxigenic treatment, both with no insurance, the simulated average net revenue was higher by $8-$10 per acre for the treatment scenario. When crop insurance was simulated, with and without atoxigenic treatments, results indicated the current RMA insurance premiums were too high for treatment scenarios. The current RMA premiums did not account for the decreased risk of insurance payout amount and frequency associated with the use of atoxigenics. Current RMA premiums were replaced with fair premiums equal to the simulated mean indemnity payment for all crop insurance options. When the treatment scenario was compared to the no treatment scenario, under the set of most efficient crop insurance options, atoxigenic treatment provided the producer with an additional net monetary benefit of $8-$16 per acre

Developing a Health Care Workforce That Supports Team-Based Care Models That Integrate Health and Social Services

Across the country, health care professionals are joining forces to improve the health care of populations with complex social, financial, and behavioral health needs. One promising approach relies on community-based integrated health teams (CIHTs), or interprofessional teams that integrate a broad range of medical, behavioral health, and social services, offer intensive case management, and link patients to available community resources. Yet whether CIHTs fulfill their potential depends in part on policymakers enacting policies that support CIHTs delivering comprehensive, high-value care to their patients. Drawing on the insights of CIHT professionals shared with the authors, this Article highlights several factors that contribute to CIHTs’ success, namely utilizing community health workers (CHWs) to provide patients with high-touch care, including behavioral health experts on the care team, and increasing coordination between CIHTs and patients’ primary care providers. The Article then calls for federal and state policies that would promote expansion of the CHW and behavioral health workforce, provide more flexible and sustainable financing to CIHTs, and support primary care providers acquiring the financial resources, data capabilities, and personnel needed to either embedding CIHTs within their practices or coordinate with outside CIHTs

Guidelines for randomized clinical trial protocol content: a systematic review

BACKGROUND: All randomized clinical trials (RCTs) require a protocol; however, numerous studies have highlighted protocol deficiencies. Reporting guidelines may improve the content of research reports and, if developed using robust methods, may increase the utility of reports to stakeholders. The objective of this study was to systematically identify and review RCT protocol guidelines, to assess their characteristics and methods of development, and to compare recommendations. METHODS: We conducted a systematic review of indexed literature (MEDLINE, EMBASE and the Cochrane Methodology Register from inception to September 2010; reference lists; related article features; forward citation searching) and a targeted search of supplementary sources, including a survey of major trial funding agencies in six countries. Records were eligible if they described a content guideline in English or French relevant to RCT protocols. Guidelines were excluded if they specified content for protocols for trials of specific procedures or conditions or were intended to assess trial quality. We extracted guideline characteristics and methods. Content was mapped for a subset of guidelines that described development methods or had institutional endorsement. RESULTS: Forty guidelines published in journals, books and institutional reports were included in the review; seven were specific to RCT protocols. Only eight (20%) described development methods which included informal consensus methods, pilot testing and formal validation; no guideline described all of these methods. No guideline described formal consensus methods or a systematic retrieval of empirical evidence to inform its development. The guidelines included a median of 23 concepts per guideline (interquartile range (IQR) = 14 to 34; range = 7 to 109). Among the subset of guidelines (n = 23) for which content was mapped, approximately 380 concepts were explicitly addressed (median concepts per guideline IQR = 31 (24,80); range = 16 to 150); most concepts were addressed in a minority of guidelines. CONCLUSIONS: Existing guidelines for RCT protocol content varied substantially in their recommendations. Few reports described the methods of guideline development, limiting comparisons of guideline validity. Given the importance of protocols to diverse stakeholders, we believe a systematically developed, evidence-informed guideline for clinical trial protocols is needed

Early Metal Di(pyridyl) Pyrrolide Complexes with Second Coordination Sphere Arene−π Interactions: Ligand Binding and Ethylene Polymerization

Early metal complexes supported by hemilabile, monoanionic di(pyridyl) pyrrolide ligands substituted with mesityl and anthracenyl groups were synthesized to probe the possibility of second coordination sphere arene−π interactions with ligands with potential for allosteric control in coordination chemistry, substrate activation, and olefin polymerization. Yttrium alkyl, indolide, and amide complexes were prepared and structurally characterized; close contacts between the anthracenyl substituents and Y-bound ligands are observed in the solid state. Titanium, zirconium, and hafnium tris(dimethylamido) complexes were synthesized, and their ethylene polymerization activity was tested. In the solid state structure of one of the Ti tris(dimethylamido) complexes, coordination of Ti to only one of the pyridine donors is observed pointing to the hemilabile character of the di(pyridyl) pyrrolide ligands

Simulation and Characterization of a Miniaturized Scanning Electron Microscope

A miniaturized Scanning Electron Microscope (mSEM) for in-situ lunar investigations is being developed at NASA Marshall Space Flight Center with colleagues from the University of Alabama in Huntsville (UAH), Advanced Research Systems (ARS), the University of Tennessee in Knoxville (UTK) and Case Western Reserve University (CWRU). This effort focuses on the characterization of individual components of the mSEM and simulation of the complete system. SEMs can provide information on the size, shape, morphology and chemical composition of lunar regolith. Understanding these basic properties will allow us to better estimate the challenges associated with In-Situ Resource Utilization and to improve our basic science knowledge of the lunar surface (either precluding the need for sample return or allowing differentiation of unique samples to be returned to Earth.) The main components of the mSEM prototype includes: a cold field emission electron gun (CFEG), focusing lens, deflection/scanning system and backscatter electron detector. Of these, the electron gun development is of particular importance as it dictates much of the design of the remaining components. A CFEG was chosen for use with the lunar mSEM as its emission does not depend on heating of the tungsten emitter (lower power), it offers a long operation lifetime, is orders of magnitude brighter than tungsten hairpin guns, has a small source size and exhibits low beam energy spread

ECJ judges read the morning papers. Explaining the turnaround of European citizenship jurisprudence

Recent jurisprudence of the European Court of Justice (ECJ) marks a striking shift towards a more restrictive interpretation of EU citizens’ rights. The Court's turnaround is not only highly relevant for practical debates about ‘Social Europe’ or ‘welfare migration’, but also enlightening from a more general, theoretical viewpoint. Several recent studies on the ECJ have argued that the Court is largely constrained by member state governments’ threats of legislative override and non-compliance. We show that an additional mechanism is necessary to explain the Court's turnaround on citizenship. While the ECJ extended EU citizens’ rights even against strong opposition by member state governments, its recent shift reflects changes in the broader political context, i.e., the politicization of free movement in the European Union (EU). The article theorises Court responsiveness to politicization and demonstrates empirically, how the Court's jurisprudence corresponds with changing public debates about EU citizenship