816 research outputs found

    Investigation of the feasibility to use Zeeman-effect background correction for the graphite furnace determination of phosphorus using high-resolution continuum source atomic absorption spectrometry as a diagnostic tool

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    The determination of phosphorus by graphite furnace atomic absorption spectrometry at the non-resonance line at 213.6 nm, and the capability of Zeeman-effect background correction (Z-BC) to deal with the fine-structured background absorption due to the PO molecule have been investigated in the presence of selected chemical modifiers. Two line source atomic absorption spectrometers, one with a longitudinally heated and the other with a transversely heated graphite tube atomizer have been used in this study, as well as two prototype high-resolution continuum source atomic absorption spectrometers, one of which had a longitudinally arranged magnet at the furnace. It has been found that Z-BC is capable correcting very well the background caused by the PO molecule, and also that of the NO molecule, which has been encountered when the Pd + Ca mixed modifier was used. Both spectra exhibited some Zeeman splitting, which, however, did not cause any artifacts or correction errors. The practical significance of this study is to confirm that accurate results can be obtained for the determination of phosphorus using Z-BC. The best sensitivity with a characteristic mass of m(0) = 11 ng P has been obtained with the pure Pd modifier, which also caused the lowest background level. The characteristic mass obtained with the mixed Pd + Ca modifier depended on the equipment used and was between m(0) = 9 ng P and m(0) = 15 ng P, and the background signal was higher. The major problem of Z-BC remains the relatively restricted linear working range

    Thin films of fluorinated 3d-metal phthalocyanines as chemical sensors of ammonia: an optical spectroscopy study

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    A comparative study of the sensor response toward gaseous ammonia of hexadecafluorinated 3d-metal phthalocyanine (MPcF16, MCu(II), Co(II), Zn(II), Ni(II)) thin films was performed using complementary experimental (viz., surface plasmon resonance, SPR, and IR absorption spectroscopy) along with theoretical (density functional theory calculations, DFT) techniques. SPR measurements revealed changes of both thickness and optical parameters (refraction indices and extinction coefficients) of the MPcF16 films caused by adsorption of NH3. The MPcF16 species studied exhibited the following order of sensor response: ZnPcF16>CoPcF16≥CuPcF16>NiPcF16. A good correlation was found between the DFT calculated (B3LYP/6-311++G(2df,p)) binding energies, experimentally measured shift of the selected IR bands, and the optical sensor response. Apart from this, we performed a detailed assignment of all intense..

    IQ-Station: A Low Cost Portable Immersive Environment

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    The emergence of inexpensive 3D TV’s, affordable input and rendering hardware and open-source software has created a yeasty atmosphere for the development of low-cost immersive environments (IE). A low cost IE system, or IQ-station, fashioned from commercial off the shelf technology (COTS), coupled with a targeted immersive application can be a viable laboratory instrument for enhancing scientific workflow for exploration and analysis. The use of an IQ-station in a laboratory setting also has the potential of quickening the adoption of a more sophisticated immersive environment as a critical enabler in modern scientific and engineering workflows. Prior work in immersive environments generally required either a head mounted display (HMD) system or a large projector-based implementation both of which have limitations in terms of cost, usability, or space requirements. The solution presented here provides an alternative platform providing a reasonable immersive experience that addresses those limitations. Our work brings together the needed hardware and software to create a fully integrated immersive display and interface system that can be readily deployed in laboratories and common workspaces. By doing so, it is now feasible for immersive technologies to be included in researchers’ day-to-day workflows. The IQ-Station sets the stage for much wider adoption of immersive environments outside the small communities of virtual reality centers

    CARD9<sup>+</sup> microglia promote antifungal immunity via IL-1β- and CXCL1-mediated neutrophil recruitment

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    This work was supported by the Intramural Research Program of the National Institute of Allergy and Infectious Disease, National Institutes of Health, as well as NIH grants awarded to TMH (R01 093808), SGF (R01AI124566) and SRL (R01CA161373). Additional funding was provided by the Burroughs Wellcome Fund (awarded to TMH), the Wellcome Trust (102705, 097377; awarded to GDB), the MRC Centre for Medical Mycology and the University of Aberdeen (MR/N006364/1; awarded to GDB). The authors additionally thank Celeste Huaman for care and screening of the Malt1 793 -/- mice.Peer reviewedPostprin

    The interplay of wind and uplift facilitates over-water flight in facultative soaring birds.

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    Flying over the open sea is energetically costly for terrestrial birds. Despite this, over-water journeys of many birds, sometimes hundreds of kilometres long, are uncovered by bio-logging technology. To understand how these birds afford their flights over the open sea, we investigated the role of atmospheric conditions, specifically wind and uplift, in subsidizing over-water flight at a global scale. We first established that ΔT, the temperature difference between sea surface and air, is a meaningful proxy for uplift over water. Using this proxy, we showed that the spatio-temporal patterns of sea-crossing in terrestrial migratory birds are associated with favourable uplift conditions. We then analysed route selection over the open sea for five facultative soaring species, representative of all major migratory flyways. The birds maximized wind support when selecting their sea-crossing routes and selected greater uplift when suitable wind support was available. They also preferred routes with low long-term uncertainty in wind conditions. Our findings suggest that, in addition to wind, uplift may play a key role in the energy seascape for bird migration that in turn determines strategies and associated costs for birds crossing ecological barriers such as the open sea

    Search for the standard model Higgs boson at LEP

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    Cognitive‐behavioral therapy in the time of coronavirus : clinician tips for working with eating disorders via telehealth when face‐to‐face meetings are not possible

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    Objective The coronavirus pandemic has led to a dramatically different way of working for many therapists working with eating disorders, where telehealth has suddenly become the norm. However, many clinicians feel ill equipped to deliver therapy via telehealth, while adhering to evidence‐based interventions. This article draws together clinician experiences of the issues that should be attended to, and how to address them within a telehealth framework. Method Seventy clinical colleagues of the authors were emailed and invited to share their concerns online about how to deliver cognitive‐behavioral therapy for eating disorders (CBT‐ED) via telehealth, and how to adapt clinical practice to deal with the problems that they and others had encountered. After 96 hr, all the suggestions that had been shared by 22 clinicians were collated to provide timely advice for other clinicians. Results A range of themes emerged from the online discussion. A large proportion were general clinical and practical domains (patient and therapist concerns about telehealth; technical issues in implementing telehealth; changes in the environment), but there were also specific considerations and clinical recommendations about the delivery of CBT‐ED methods. Discussion Through interaction and sharing of ideas, clinicians across the world produced a substantial number of recommendations about how to use telehealth to work with people with eating disorders while remaining on track with evidence‐based practice. These are shared to assist clinicians over the period of changed practice
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