665 research outputs found

    Odorant binding proteins fromHermetia illucens: potential sensing elements for detecting volatile aldehydes involved in early stages of organic decomposition

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    Organic decomposition processes, involving the breakdown of complex molecules such as carbohydrates, proteins and fats, release small chemicals known as volatile organic compounds (VOCs), smelly even at very low concentrations, but not all readily detectable by vertebrates. Many of these compounds are instead detected by insects, mostly by saprophytic species, for which long-range orientation towards organic decomposition matter is crucial. In the present work the detection of aldehydes, as an important measure of lipid oxidation, has been possible exploiting the molecular machinery underlying odour recognition inHermetia illucens(Diptera: Stratiomyidae). This voracious scavenger insect is of interest due to its outstanding capacity in bioconversion of organic waste, colonizing very diverse environments due to the ability of sensing a wide range of chemical compounds that influence the choice of substrates for ovideposition. A variety of soluble odorant binding proteins (OBPs) that may function as carriers of hydrophobic molecules from the air-water interface in the antenna of the insect to the receptors were identified, characterised and expressed. An OBP-based nanobiosensor prototype was realized using selected OBPs as sensing layers for the development of an array of quartz crystal microbalances (QCMs) for vapour phase detection of selected compounds at room temperature. QCMs coated with four recombinantH. illucensOBPs (HillOBPs) were exposed to a wide range of VOCs indicative of organic decomposition, showing a high sensitivity for the detection of three chemical compounds belonging to the class of aldehydes and one short-chain fatty acid. The possibility of using biomolecules capable of binding small ligands as reversible gas sensors has been confirmed, greatly expanding the state-of the-art in gas sensing technology

    Xenon in Mercury-Manganese Stars

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    Previous studies of elemental abundances in Mercury-Manganese (HgMn) stars have occasionally reported the presence of lines of the ionized rare noble gas Xe II, especially in a few of the hottest stars with Teff ~ 13000--15000 K. A new study of this element has been undertaken using observations from Lick Observatory's Hamilton Echelle Spectrograph. In this work, the spectrum synthesis program UCLSYN has been used to undertake abundance analysis assuming LTE. We find that in the Smith & Dworetsky sample of HgMn stars, Xe is vastly over-abundant in 21 of 22 HgMn stars studied, by factors of 3.1--4.8 dex. There does not appear to be a significant correlation of Xe abundance with Teff. A comparison sample of normal late B stars shows no sign of Xe II lines that could be detected, consistent with the expected weakness of lines at normal abundance. The main reason for the previous lack of widespread detection in HgMn stars is probably due to the strongest lines being at longer wavelengths than the photographic blue. The lines used in this work were 4603.03A, 4844.33A and 5292.22A.Comment: 8 pages, 4 figures. Accepted by Monthly Notices of the Royal Astronomical Society, 8 January 200

    An Introduction and High Yield Summary of Female Contraceptive Methods

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    Globally, contraceptive studies and their use are major challenges in the realm of public health. The ideal goal is to obtain a contraceptive method that is highly effective at minimizing unplanned pregnancies and nullifying the chance of contracting a sexually transmitted disease. Abstinence is currently the only way to attain such a dualistic goal, and while effective, it may not be suitable for sexually active individuals. While there is an abundance of methodspecific information regarding the use of any one female contraceptive device, there is a paucity of resources that compare and contrast the advantages and disadvantages of such methods and enable an individual to optimize family planning. This paper attempts to address many of these topics by reviewing a multitude of U.S. Food and Drug Administration (FDA) approved contraceptive methods. This work is intentionally written towards educating medical students, educators and teachers at all levels of training with foundational knowledge regarding female contraception

    A consideration of the challenges involved in supervising international masters students

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    This paper explores the challenges facing supervisors of international postgraduate students at the dissertation stage of the masters programme. The central problems of time pressure, language difficulties, a lack of critical analysis and a prevalence of personal problems among international students are discussed. This paper makes recommendations for the improvement of language and critical thinking skills, and questions the future policy of language requirements at HE for international Masters students

    Emerging models and trends in mental health crisis care in England: a national investigation of crisis care systems

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    Background: Inpatient psychiatric care is unpopular and expensive, and development and evaluation of alternatives is a long-standing policy and research priority around the world. In England, the three main models documented over the past fifty years (teams offering crisis assessment and treatment at home; acute day units; and residential crisis services in the community) have recently been augmented by several new service models. These are intended to enhance choice and flexibility within catchment area acute care systems, but remain largely undocumented in the research literature. We therefore aimed to describe the types and distribution of crisis care models across England through a national survey. Methods: We carried out comprehensive mapping of crisis resolution teams (CRTs) using previous surveys, websites and multiple official data sources. Managers of CRTs were invited to participate as key informants who were familiar with the provision and organisation of crisis care services within their catchment area. The survey could be completed online or via telephone interview with a researcher, and elicited details about types of crisis care delivered in the local catchment area. // Results: We mapped a total of 200 adult CRTs and completed the survey with 184 (92%). Of the 200 mapped adult CRTs, there was a local (i.e., within the adult CRT catchment area) children and young persons CRT for 84 (42%), and an older adults CRT for 73 (37%). While all but one health region in England provided CRTs for working age adults, there was high variability regarding provision of all other community crisis service models and system configurations. Crisis cafes, street triage teams and separate crisis assessment services have all proliferated since a similar survey in 2016, while provision of acute day units has reduced. // Conclusions: The composition of catchment area crisis systems varies greatly across England and popularity of models seems unrelated to strength of evidence. A group of emerging crisis care models with varying functions within service systems are increasingly prevalent: they have potential to offer greater choice and flexibility in managing crises, but an evidence base regarding impact on service user experiences and outcomes is yet to be established

    Ethnic differences in receipt of psychological interventions in Early Intervention in Psychosis services in England – a cross-sectional study

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    There is some evidence of differences in psychosis care provision by ethnicity. We investigated variations in the receipt of Cognitive Behavioural Therapy for psychosis (CBTp) and family intervention across ethnic groups in Early Intervention in Psychosis (EIP) teams throughout England, where national policy mandates offering these interventions to all. We included data on 29,610 service users from the National Clinical Audit of Psychosis (NCAP), collected between 2018 and 2021. We conducted mixed effects logistic regression analyses to examine odds ratios of receiving an intervention (CBTp, family intervention, either intervention) across 17 ethnic groups while accounting for the effect of years and variance between teams and adjusting for individual- (age, gender, occupational status) and team-level covariates (care-coordinator caseload, inequalities strategies). Compared with White British people, every minoritized ethnic group, except those of mixed Asian-White and mixed Black African-White ethnicities, had significantly lower adjusted odds of receiving CBTp. People of Black African, Black Caribbean, non-African/Caribbean Black, non-British/Irish White, and of “any other” ethnicity also experienced significantly lower adjusted odds of receiving family intervention. Pervasive inequalities in receiving CBTp for first episode psychosis exist for almost all minoritized ethnic groups, and family intervention for many groups. Investigating how these inequalities arise should be a research priority
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