Growth of thin films of molybdenum and tungsten oxides by combustion CVD using aqueous precursor solutions

Using combustion chemical vapour deposition, layers of molybdenum and tungsten oxides have been deposited on glass and silicon at low temperatures. Inexpensive ammonium salts of molybdate and metatungstate ions were used as precursors and were delivered to the coating flame as an aqueous solution using a nebuliser. The resulting films were analysed by scanning electron microscopy (SEM), energy dispersive analysis of X-rays (EDAX), Rutherford backscattering (RBS), X-ray photoelectron spectroscopy (XPS) and X-ray diffraction (XRD). These indicate that the films are continuous, moderately smooth and consist of amorphous, disordered molybdenum and tungsten trioxides

A Principles-Based Response to the Proposed Reform of the Governance Structure for Listing Regulation in Hong Kong

The June 2016 joint consultation on listing regulation arises out of a renewed concern to ensure the Hong Kong market remains fit for purpose in meeting current and emergent challenges and demands. This paper undertakes an analysis of the consultation applying a law and principles based approach. This approach requires the listing regime to be suitable not only in view of market conditions but also in view of internationally accepted practices and standards concerning regulatory oversight. While it is recognized that regulatory evolution requires progressive innovation, the two new SEHK sub-committees envisaged by the joint consultation give rise to several areas of concern. The reasons for implementing the changes proposed are not well explained in the consultation and no clear case is presented as to why the sub-committee structure would provide improvements. Putting the SFC into a frontline decision-making role is problematic under the current statutory framework, and is not necessarily a forward moving step toward a system of statutory listing regulation. It implements changes that bypass legislative intent and renders certain statutory laws meaningless, it may subject the SFC to corporate laws that would impact on its ability to act as an independent regulator, and it would diminish regulatory accountability and clarity. The risk that the changes could be regarded as legislation by regulation would weaken, not strengthen, the SFC’s regulatory mandate over public listings. These problems run counter to the intent of the Proposal to improve listing regulation and carry the risk that Hong Kong’s governance of listings, particularly the role of the statutory regulator in it, would be at odds with international best practices. The conclusion of this paper is that progressing with the sub-committee proposal would not be a positive development unless and until the issues identified in this paper are properly addressed and resolved. It is suggested that a more holistic view of market development needs to be adopted that extends beyond the decision making mechanisms of the dual filing regime and identifies more precisely the specific issues that are problematic. Doing so would permit more targeted and sustainable oversight mechanisms to be developed.postprin

Probabilistic divergence time estimation without branch lengths: dating the origins of dinosaurs, avian flight and crown birds

Branch lengths—measured in character changes—are an essential requirement of clock-based divergence estimation, regardless of whether the fossil calibrations used represent nodes or tips. However, a separate set of divergence time approaches are typically used to date palaeontological trees, which may lack such branch lengths. Among these methods, sophisticated probabilistic approaches have recently emerged, in contrast with simpler algorithms relying on minimum node ages. Here, using a novel phylogenetic hypothesis for Mesozoic dinosaurs, we apply two such approaches to estimate divergence times for: (i) Dinosauria, (ii) Avialae (the earliest birds) and (iii) Neornithes (crown birds). We find: (i) the plausibility of a Permian origin for dinosaurs to be dependent on whether Nyasasaurus is the oldest dinosaur, (ii) a Middle to Late Jurassic origin of avian flight regardless of whether Archaeopteryx or Aurornis is considered the first bird and (iii) a Late Cretaceous origin for Neornithes that is broadly congruent with other node- and tip-dating estimates. Demonstrating the feasibility of probabilistic time-scaling further opens up divergence estimation to the rich histories of extinct biodiversity in the fossil record, even in the absence of detailed character data

Health literacy, health status, and healthcare utilization of Taiwanese adults: results from a national survey

Abstract Background Low health literacy is considered a worldwide health threat. The purpose of this study is to assess the prevalence and socio-demographic covariates of low health literacy in Taiwanese adults and to investigate the relationships between health literacy and health status and health care utilization. Methods A national survey of 1493 adults was conducted in 2008. Health literacy was measured using the Mandarin Health Literacy Scale. Health status was measured based on self-rated physical and mental health. Health care utilization was measured based on self-reported outpatient clinic visits, emergency room visits, and hospitalizations. Results Approximately thirty percent of adults were found to have low (inadequate or marginal) health literacy. They tended to be older, have fewer years of schooling, lower household income, and reside in less populated areas. Inadequate health literacy was associated with poorer mental health (OR, 0.57; 95% CI, 0.35-0.91). No association was found between health literacy and health care utilization even after adjusting for other covariates. Conclusions Low (inadequate and marginal) health literacy is prevalent in Taiwan. High prevalence of low health literacy is not necessarily indicative of the need for interventions. Systematic efforts to evaluate the impact of low health literacy on health outcomes in other countries would help to illuminate features of health care delivery and financing systems that may mitigate the adverse health effects of low health literacy.http://deepblue.lib.umich.edu/bitstream/2027.42/78252/1/1471-2458-10-614.xmlhttp://deepblue.lib.umich.edu/bitstream/2027.42/78252/2/1471-2458-10-614.pdfPeer Reviewe

Npas4 is activated by melatonin, and drives the clock gene Cry1 in the ovine pars tuberalis

Seasonal mammalsintegrate changes in the duration of nocturnal melatonin secretion to drive annual physiologic cycles. Melatonin receptors within the proximal pituitary region, the pars tuberalis (PT), are essential in regulating seasonal neuroendocrine responses. In the ovine PT, melatonin is known to influence acute changes in transcriptional dynamics coupled to the onset (dusk) and offset (dawn) of melatonin secretion, leading to a potential interval-timing mechanism capable of decoding changes in day length (photoperiod). Melatonin offset at dawn is linked to cAMP accumulation, which directly induces transcription of the clock gene Per1. The rise of melatonin at dusk induces a separate and distinct cohort, including the clock-regulated genes Cry1 and Nampt, but little is known of the upstream mechanisms involved. Here, we used next-generation sequencing of the ovine PT transcriptome at melatonin onset and identified Npas4 as a rapidly induced basic helix-loop-helix Per-Arnt-Sim domain transcription factor. In vivo we show nuclear localization of NPAS4 protein in presumptive melatonin target cells of the PT (α-glycoprotein hormone-expressing cells), whereas in situ hybridization studies identified acute and transient expression in the PT of Npas4 in response to melatonin. In vitro, NPAS4 forms functional dimers with basic helix loop helix-PAS domain cofactors aryl hydrocarbon receptor nuclear translocator (ARNT), ARNT2, and ARNTL, transactivating both Cry1 and Nampt ovine promoter reporters. Using a combination of 5'-deletions and site-directed mutagenesis, we show NPAS4-ARNT transactivation to be codependent upon two conserved central midline elements within the Cry1 promoter. Our data thus reveal NPAS4 as a candidate immediate early-response gene in the ovine PT, driving molecular responses to melatonin

A pentapeptide as minimal antigenic determinant for MHC class I-restricted T lymphocytes

Peptides that are antigenic for T lymphocytes are ligands for two receptors, the class I or II glycoproteins that are encoded by genes in the major histocompatibility complex, and the idiotypic / chain T-cell antigen receptor1–9. That a peptide must bind to an MHC molecule to interact with a T-cell antigen receptor is the molecular basis of the MHC restriction of antigen-recognition by T lymphocytes10,11. In such a trimolecular interaction the amino-acid sequence of the peptide must specify the contact with both receptors: agretope residues bind to the MHC receptor and epitope residues bind to the T-cell antigen receptor12,13. From a compilation of known antigenic peptides, two algorithms have been proposed to predict antigenic sites in proteins. One algorithm uses linear motifs in the sequence14, whereas the other considers peptide conformation and predicts antigenicity for amphipathic -helices15,16. We report here that a systematic delimitation of an antigenic site precisely identifies a predicted pentapeptide motif as the minimal antigenic determinant presented by a class I MHC molecule and recognized by a cytolytic T lymphocyte clone

Quantifying full phenological event distributions reveals simultaneous advances, temporal stability and delays in spring and autumn migration timing in long-distance migratory birds

Acknowledgements We thank all Fair Isle Bird Observatory staff and volunteers for help with data collection and acknowledge the foresight of George Waterston and Ken Williamson in instigating the observatory and census methodology. We thank all current and previous directors of Fair Isle Bird Observatory Trust for their contributions, particularly Dave Okill and Mike Wood for their stalwart support for the long-term data collection and for the current analyses. Dawn Balmer and Ian Newton provided helpful guidance on manuscript drafts. We thank Ally Phillimore and two anonymous referees for helpful comments. This study would have been impossible without the Fair Isle community's invaluable support and patience over many decades, which is very gratefully acknowledged. WTSM and JMR designed and undertook analyses, wrote the paper and contributed to data collection and compilation, MB contributed to analysis and editing, all other authors oversaw and undertook data collection and compilation and contributed to editing.Peer reviewedPostprin

Engaging Undergraduates in Science Research: Not Just About Faculty Willingness.

Despite the many benefits of involving undergraduates in research and the growing number of undergraduate research programs, few scholars have investigated the factors that affect faculty members' decisions to involve undergraduates in their research projects. We investigated the individual factors and institutional contexts that predict faculty members' likelihood of engaging undergraduates in their research project(s). Using data from the Higher Education Research Institute's 2007-2008 Faculty Survey, we employ hierarchical generalized linear modeling to analyze data from 4,832 science, technology, engineering, and mathematics (STEM) faculty across 194 institutions to examine how organizational citizenship behavior theory and social exchange theory relate to mentoring students in research. Key findings show that faculty who work in the life sciences and those who receive government funding for their research are more likely to involve undergraduates in their research project(s). In addition, faculty at liberal arts or historically Black colleges are significantly more likely to involve undergraduate students in research. Implications for advancing undergraduate research opportunities are discussed

Beyond Gross-Pitaevskii Mean Field Theory

A large number of effects related to the phenomenon of Bose-Einstein Condensation (BEC) can be understood in terms of lowest order mean field theory, whereby the entire system is assumed to be condensed, with thermal and quantum fluctuations completely ignored. Such a treatment leads to the Gross-Pitaevskii Equation (GPE) used extensively throughout this book. Although this theory works remarkably well for a broad range of experimental parameters, a more complete treatment is required for understanding various experiments, including experiments with solitons and vortices. Such treatments should include the dynamical coupling of the condensate to the thermal cloud, the effect of dimensionality, the role of quantum fluctuations, and should also describe the critical regime, including the process of condensate formation. The aim of this Chapter is to give a brief but insightful overview of various recent theories, which extend beyond the GPE. To keep the discussion brief, only the main notions and conclusions will be presented. This Chapter generalizes the presentation of Chapter 1, by explicitly maintaining fluctuations around the condensate order parameter. While the theoretical arguments outlined here are generic, the emphasis is on approaches suitable for describing single weakly-interacting atomic Bose gases in harmonic traps. Interesting effects arising when condensates are trapped in double-well potentials and optical lattices, as well as the cases of spinor condensates, and atomic-molecular coupling, along with the modified or alternative theories needed to describe them, will not be covered here.Comment: Review Article (19 Pages) - To appear in 'Emergent Nonlinear Phenomena in Bose-Einstein Condensates: Theory and Experiment', Edited by P.G. Kevrekidis, D.J. Frantzeskakis and R. Carretero-Gonzalez (Springer Verlag