574 research outputs found

    G-300: The first French Getaway Special microgravity measurements of fluid thermal conductivity

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    Thermal conductivity measurements on liquids are difficult to perform on Earth because of thermal motions due to convection. In microgravity, the convection due to buoyancy is evanescent, and a strong reduction of Rayleigh and Nusselt numbers can be expected. Three low viscosity liquids are selected to carry out the measurements; distilled water (standard) and two silicone oils. A modified hot plate method with a simplified guard ring is used; the reduction of convective motions permitted the use in the experimental cells of larger interplate distances and/or temperature differences than in Earth measurements, improving the accuracy. Comparisons between Earth and orbit results may help to understand the convection occurrence in the cells. Thermal, vibrational, and EMI tests have proved that the design satisfies the NASA requirements

    Small Molecule Enhancers of Endosome-to-Cytosol Import Augment Anti-tumor Immunity

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    Cross-presentation of antigens by dendritic cells (DCs) is critical for initiation of anti-tumor immune responses. Yet, key steps involved in trafficking of antigens taken up by DCs remain incompletely understood. Here, we screen 700 US Food and Drug Administration (FDA)-approved drugs and identify 37 enhancers of antigen import from endolysosomes into the cytosol. To reveal their mechanism of action, we generate proteomic organellar maps of control and drug-treated DCs (focusing on two compounds, prazosin and tamoxifen). By combining organellar mapping, quantitative proteomics, and microscopy, we conclude that import enhancers undergo lysosomal trapping leading to membrane permeation and antigen release. Enhancing antigen import facilitates cross-presentation of soluble and cell-associated antigens. Systemic administration of prazosin leads to reduced growth of MC38 tumors and to a synergistic effect with checkpoint immunotherapy in a melanoma model. Thus, inefficient antigen import into the cytosol limits antigen cross-presentation, restraining the potency of anti-tumor immune responses and efficacy of checkpoint blockers

    Global Disease Outbreaks Associated with the 2015–2016 El Niño Event

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    Interannual climate variability patterns associated with the El Niño-Southern Oscillation phenomenon result in climate and environmental anomaly conditions in specific regions worldwide that directly favor outbreaks and/or amplification of variety of diseases of public health concern including chikungunya, hantavirus, Rift Valley fever, cholera, plague, and Zika. We analyzed patterns of some disease outbreaks during the strong 2015–2016 El Niño event in relation to climate anomalies derived from satellite measurements. Disease outbreaks in multiple El Niño-connected regions worldwide (including Southeast Asia, Tanzania, western US, and Brazil) followed shifts in rainfall, temperature, and vegetation in which both drought and flooding occurred in excess (14–81% precipitation departures from normal). These shifts favored ecological conditions appropriate for pathogens and their vectors to emerge and propagate clusters of diseases activity in these regions. Our analysis indicates that intensity of disease activity in some ENSO-teleconnected regions were approximately 2.5–28% higher during years with El Niño events than those without. Plague in Colorado and New Mexico as well as cholera in Tanzania were significantly associated with above normal rainfall (p \u3c 0.05); while dengue in Brazil and southeast Asia were significantly associated with above normal land surface temperature (p \u3c 0.05). Routine and ongoing global satellite monitoring of key climate variable anomalies calibrated to specific regions could identify regions at risk for emergence and propagation of disease vectors. Such information can provide sufficient lead-time for outbreak prevention and potentially reduce the burden and spread of ecologically coupled diseases

    Structure–property relation and relevance of beam theories for microtubules: a coupled molecular and continuum mechanics study

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    Quasi-one-dimensional microtubules (MTs) in cells enjoy high axial rigidity but large transverse flexibility due to the inter-protofilament (PF) sliding. This study aims to explore the structure–property relation for MTs and examine the relevance of the beam theories to their unique features. A molecular structural mechanics (MSM) model was used to identify the origin of the inter-PF sliding and its role in bending and vibration of MTs. The beam models were then fitted to the MSM to reveal how they cope with the distinct mechanical responses induced by the inter-PF sliding. Clear evidence showed that the inter-PF sliding is due to the soft inter-PF bonds and leads to the length-dependent bending stiffness. The Euler beam theory is found to adequately describe MT deformation when the inter-PF sliding is largely prohibited. Nevertheless, neither shear deformation nor the nonlocal effect considered in the ‘more accurate’ beam theories can fully capture the effect of the inter-PF sliding. This reflects the distinct deformation mechanisms between an MT and its equivalent continuous body

    Optimising observing strategies for monitoring animals using drone-mounted thermal infrared cameras

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    The proliferation of relatively affordable off-the-shelf drones offers great opportunities for wildlife monitoring and conservation. Similarly the recent reduction in cost of thermal infrared cameras also offers new promise in this field, as they have the advantage over conventional RGB cameras of being able to distinguish animals based on their body heat and being able to detect animals at night. However, the use of drone-mounted thermal infrared cameras comes with several technical challenges. In this paper we address some of these issues, namely thermal contrast problems due to heat from the ground, absorption and emission of thermal infrared radiation by the atmosphere, obscuration by vegetation, and optimizing the flying height of drones for a best balance between covering a large area and being able to accurately image and identify animals of interest. We demonstrate the application of these methods with a case study using field data, and make the first ever detection of the critically endangered riverine rabbit (Bunolagus monticularis) in thermal infrared data. We provide a web-tool so that the community can easily apply these techniques to other studies (http://www.astro.ljmu.ac.uk/~aricburk/uav_calc/)

    Detailed spectral and morphological analysis of the shell type SNR RCW 86

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    Aims: We aim for an understanding of the morphological and spectral properties of the supernova remnant RCW~86 and for insights into the production mechanism leading to the RCW~86 very high-energy gamma-ray emission. Methods: We analyzed High Energy Spectroscopic System data that had increased sensitivity compared to the observations presented in the RCW~86 H.E.S.S. discovery publication. Studies of the morphological correlation between the 0.5-1~keV X-ray band, the 2-5~keV X-ray band, radio, and gamma-ray emissions have been performed as well as broadband modeling of the spectral energy distribution with two different emission models. Results:We present the first conclusive evidence that the TeV gamma-ray emission region is shell-like based on our morphological studies. The comparison with 2-5~keV X-ray data reveals a correlation with the 0.4-50~TeV gamma-ray emission.The spectrum of RCW~86 is best described by a power law with an exponential cutoff at Ecut=(3.5±1.2stat)E_{cut}=(3.5\pm 1.2_{stat}) TeV and a spectral index of Γ\Gamma~1.6±0.21.6\pm 0.2. A static leptonic one-zone model adequately describes the measured spectral energy distribution of RCW~86, with the resultant total kinetic energy of the electrons above 1 GeV being equivalent to ∼\sim0.1\% of the initial kinetic energy of a Type I a supernova explosion. When using a hadronic model, a magnetic field of BB~100μ\muG is needed to represent the measured data. Although this is comparable to formerly published estimates, a standard E−2^{-2} spectrum for the proton distribution cannot describe the gamma-ray data. Instead, a spectral index of Γp\Gamma_p~1.7 would be required, which implies that ~7×1049/ncm−37\times 10^{49}/n_{cm^{-3}}erg has been transferred into high-energy protons with the effective density ncm−3=n/1n_{cm^{-3}}=n/ 1 cm^-3. This is about 10\% of the kinetic energy of a typical Type Ia supernova under the assumption of a density of 1~cm^-3.Comment: accepted for publication by A&

    Beyond traditional surveillance: applying syndromic surveillance to developing settings – opportunities and challenges

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    <p>Abstract</p> <p>Background</p> <p>All countries need effective disease surveillance systems for early detection of outbreaks. The revised International Health Regulations [IHR], which entered into force for all 194 World Health Organization member states in 2007, have expanded traditional infectious disease notification to include surveillance for public health events of potential international importance, even if the causative agent is not yet known. However, there are no clearly established guidelines for how countries should conduct this surveillance, which types of emerging disease syndromes should be reported, nor any means for enforcement.</p> <p>Discussion</p> <p>The commonly established concept of syndromic surveillance in developed regions encompasses the use of pre-diagnostic information in a near real time fashion for further investigation for public health action. Syndromic surveillance is widely used in North America and Europe, and is typically thought of as a highly complex, technology driven automated tool for early detection of outbreaks. Nonetheless, low technology applications of syndromic surveillance are being used worldwide to augment traditional surveillance.</p> <p>Summary</p> <p>In this paper, we review examples of these novel applications in the detection of vector-borne diseases, foodborne illness, and sexually transmitted infections. We hope to demonstrate that syndromic surveillance in its basic version is a feasible and effective tool for surveillance in developing countries and may facilitate compliance with the new IHR guidelines.</p

    Social media use, attitudes, behaviours and perceptions of online professionalism amongst dental students

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    Use of social media has increased amongst health professionals. This has benefits for patient care but also introduces risks for confidentiality and professional fitness to practise. This study aimed to examine dental student attitudes towards professional behaviour on social media. The secondary aim was to establish the extent and nature of social media use and exposure to potentially unprofessional behaviours. A cross-sectional study was carried out in one dental school. Data were collected using questionnaires to examine social media use, perceptions and attitudes towards social media and professional behaviours online. Students who responded (n=155) all used social media at least once per week; most used more than one platform. Students were aware of the relationship between social media use and professional practice. Posting drunken photographs and interacting with staff and patients online were widely considered as unprofessional. Security settings affected behaviour and most had seen inappropriate behaviours online. Students use social media extensively. Students are aware of the risks but there is a greater sense of safety in closed groups and many students are exposed to potentially inappropriate content online. This suggests that there are opportunities to reduce these risks through training to help students manage these risks

    Global Disease Outbreaks Associated with the 2015-2016 El Nio Event

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    Interannual climate variability patterns associated with the El Nio-Southern Oscillation phenomenon result in climate and environmental anomaly conditions in specific regions worldwide that directly favor outbreaks and/or amplification of variety of diseases of public health concern including chikungunya, hantavirus, Rift Valley fever, cholera, plague, and Zika. We analyzed patterns of some disease outbreaks during the strong 20152016 El Nio event in relation to climate anomalies derived from satellite measurements. Disease outbreaks in multiple El Nio-connected regions worldwide (including Southeast Asia, Tanzania, western US, and Brazil) followed shifts in rainfall, temperature, and vegetation in which both drought and flooding occurred in excess (1481% precipitation departures from normal). These shifts favored ecological conditions appropriate for pathogens and their vectors to emerge and propagate clusters of diseases activity in these regions. Our analysis indicates that intensity of disease activity in some ENSO-teleconnected regions were approximately 2.528% higher during years with El Nio events than those without. Plague in Colorado and New Mexico as well as cholera in Tanzania were significantly associated with above normal rainfall (p < 0.05); while dengue in Brazil and southeast Asia were significantly associated with above normal land surface temperature (p < 0.05). Routine and ongoing global satellite monitoring of key climate variable anomalies calibrated to specific regions could identify regions at risk for emergence and propagation of disease vectors. Such information can provide sufficient lead-time for outbreak prevention and potentially reduce the burden and spread of ecologically coupled diseases

    Older and wiser? First year BDS graduate entry students and their views on using social media and professional practice

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    Introduction The use of social media sites (SMS) has increased exponentially since their creation and introduction in the early 2000s. The number of regular users of SMS is estimated at over two billion people worldwide. Ethical and legal guidelines exert an additional responsibility on the behaviour of both graduate and undergraduate dentists when compared to members of the general public with some assumption that life experience can offer some insight into attitudes about online use of social media in relation to professional practice. Aim We set out to explore the views of the first year graduate entry programme students at the University of Central Lancashire and their use of SMS together with their opinions on what they consider to be professional online behaviour. Methods A mixed-methods approach was adopted with a questionnaire and semi-structured interviews which were designed to elicit the students' opinions. Results For this group of students, 100% were using social media sites and some were aware of some of their limitations and possible impact on their careers. There was some rather superficial knowledge of what is and is not professional to post via social media, however, students were not fully aware about the legal and ethical guidelines in place in relation to the topic. Conclusion Results from this study present an opportunity and a challenge for educators to incorporate additional details not only about professionalism and ethical and legal aspects within the undergraduate curriculum but more specific emphasis on the use of social media as part of the undergraduate BDS course
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