Interpretation of dispersion relations for bounded systems

Constructing normal modes for bounded systems from infinite dispersion relation roots for interpretation of plasma wave and instability studies on finite cylinder

The Albia Research Farm

Born in the Great Depression, it first provided labor for unemployed workers. Since then, it has spearheaded southern Iowa research efforts in pasture improvement and brush control, birdsfoot trefoil, and beef cattle breeding

High Discordance of Chest X-ray and CT for Detection of Pulmonary Opacities in ED Patients: Implications for Diagnosing Pneumonia

Objective To evaluate the diagnostic performance of chest x-ray (CXR) compared to computed tomography (CT) for detection of pulmonary opacities in adult emergency department (ED) patients. Methods We conducted an observational cross-sectional study of adult patients presenting to 12 EDs in the United States from July 1, 2003, through November 30, 2006, who underwent both CXR and chest CT for routine clinical care. CXRs and CT scans performed on the same patient were matched. CXRs and CT scans were interpreted by attending radiologists and classified as containing pulmonary opacities if the final radiologist report noted opacity, infiltrate, consolidation, pneumonia, or bronchopneumonia. Using CT as a criterion standard, the diagnostic test characteristics of CXR to detect pulmonary opacities were calculated. Results The study cohort included 3423 patients. Shortness of breath, chest pain and cough were the most common complaints, with 96.1% of subjects reporting at least one of these symptoms. Pulmonary opacities were visualized on 309 (9.0%) CXRs and 191 (5.6 %) CT scans. CXR test characteristics for detection of pulmonary opacities included: sensitivity 43.5% (95% CI, 36.4%-50.8%); specificity 93.0% (95% CI, 92.1%-93.9%); positive predictive value 26.9% (95% CI, 22.1%-32.2%); and negative predictive value 96.5% (95% CI, 95.8%-97.1%). Conclusion In this multicenter cohort of adult ED patients with acute cardiopulmonary symptoms, CXR demonstrated poor sensitivity and positive predictive value for detecting pulmonary opacities. Reliance on CXR to identify pneumonia may lead to significant rates of misdiagnosis

Ion Transport and the True Transference Number in Nonaqueous Polyelectrolyte Solutions for Lithium Ion Batteries.

Nonaqueous polyelectrolyte solutions have been recently proposed as high Li+ transference number electrolytes for lithium ion batteries. However, the atomistic phenomena governing ion diffusion and migration in polyelectrolytes are poorly understood, particularly in nonaqueous solvents. Here, the structural and transport properties of a model polyelectrolyte solution, poly(allyl glycidyl ether-lithium sulfonate) in dimethyl sulfoxide, are studied using all-atom molecular dynamics simulations. We find that the static structural analysis of Li+ ion pairing is insufficient to fully explain the overall conductivity trend, necessitating a dynamic analysis of the diffusion mechanism, in which we observe a shift from largely vehicular transport to more structural diffusion as the Li+ concentration increases. Furthermore, we demonstrate that despite the significantly higher diffusion coefficient of the lithium ion, the negatively charged polyion is responsible for the majority of the solution conductivity at all concentrations, corresponding to Li+ transference numbers much lower than previously estimated experimentally. We quantify the ion-ion correlations unique to polyelectrolyte systems that are responsible for this surprising behavior. These results highlight the need to reconsider the approximations typically made for transport in polyelectrolyte solutions

Learning to use discourse analysis on a professional psychology training programme: accounts of supervisees and a supervisor

Qualitative research methods have become more prominent in professional psychology training over recent years, yet there are relatively few published accounts of how students learn to use these methods. In this article we describe the experiences of British trainee clinical psychologists as they learn to use one qualitative method, Discourse Analysis, for their major research project. Based on these experiences, we discuss key aspects of the research process (e.g. supervision) and delineate dilemmas, theoretical questions, suggestions and practical advice. Extracts from a group discussion involving the supervisor and supervisees (after the trainees had completed their studies) are provided to illustrate some of these themes

A Screening tool for Identification of Victims of Commercial Sexual Exploitation of Children

Background: Commercial sexual exploitation of children (CSEC) and sex trafficking have only recently been recognized as problems by healthcare providers. Both UNICEF (2014) and the Institute of Medicine (2013) have stressed the need for systematic research to assist healthcare providers in the identification of victims. The aim of this poster is to describe initial findings relating to the development of a screening tool to identify CSEC victims. Methods: Twenty-seven sites nationwide (e.g., emergency departments and specialized clinics) participated in a study to validate a screening tool for identifying CSEC victims in an outpatient setting. The study was conducted under approval from the Institutional Review Board at Children’s Healthcare of Atlanta. Inclusion criteria for the study generally involved being an English-speaking adolescent aged 11-18 years. Results: Study enrollment is ongoing. Preliminary data for 210 youth were analyzed for this abstract. The sample was diverse with respect to age (M=14.59 years, SD=1.490 years) and ethnicity (56.4% Caucasian, 31.8% African American, 3.9% mixed race, and 7.8% Hispanic); the sample was predominantly female (92.8%). Of the 210 youth in the sample, 115(54.8%) have had sex. Of these 115 youth, 13(11.3%) have traded sex for money, drugs, or housing; 7(58.3%) of 12(10.4%) complied when asked by someone to have sex with another person; 8(61.5%) of 13(11.3%) performed sexual acts in public when propositioned; and 19(45.2%) of 42(36.5%) shared provocative photos when prompted. Medical providers flagged 14 youth (6.7% of total 210) as potential CSEC victims. Conclusions: The screening tool shows promise for effective identification of CSEC victims. This poster will present additional data and further quantitative analyses exploring the influences of sexual behavior, drug and alcohol use, and other factors on the risk of becoming a CSEC victim. Implications for researchers and clinicians will also be discussed

Dimerization of ABCG2 Analysed by Bimolecular Fluorescence Complementation

ABCG2 is one of three human ATP binding cassette transporters that are functionally capable of exporting a diverse range of substrates from cells. The physiological consequence of ABCG2 multidrug transport activity in leukaemia, and some solid tumours is the acquisition of cancer multidrug resistance. ABCG2 has a primary structure that infers that a minimal functional transporting unit would be a homodimer. Here we investigated the ability of a bimolecular fluorescence complementation approach to examine ABCG2 dimers, and to probe the role of individual amino acid substitutions in dimer formation. ABCG2 was tagged with fragments of venus fluorescent protein (vYFP), and this tagging did not perturb trafficking or function. Co-expression of two proteins bearing N-terminal and C-terminal fragments of YFP resulted in their association and detection of dimerization by fluorescence microscopy and flow cytometry. Point mutations in ABCG2 which may affect dimer formation were examined for alterations in the magnitude of fluorescence complementation signal. Bimolecular fluorescence complementation (BiFC) demonstrated specific ABCG2 dimer formation, but no changes in dimer formation, resulting from single amino acid substitutions, were detected by BiFC analysis