2,218 research outputs found

    Structurally Integrated Antennas on a Joined-Wing Aircraft

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    This research is a foundational study of conformal, load-bearing antenna arrays embedded into the wing structure of a joined-wing aircraft. It is a multidisciplinary effort that touches on the aerodynamic structural and electromagnetic design considerations that stem from this unique type of sensor integration. The antenna performance Finite Element Model (FEM) and control surface effectiveness are investigated. The theory describing an ensemble of dipole antenna elements that conform to the shape of a section of the joined wing is developed. The far held flee space radiation pattern of the sensor is then analyzed for a wing that is deflected due to typical aerodynamic loading. This pattern is compared to the same antenna when the wing is not deformed. A FEM of the antenna elements is created and incorporated into the hill FEM of the joined-wing aircraft allowing its structural impact to be realized. Based on the positioning of these large sensor arrays control surfaces are placed and examined to achieve the proper handling capabilities necessary for this type of aircraft

    USDA's Healthy Eating Index and Nutrition Information

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    A comprehensive model is developed to measure the extent that nutrition knowledge and diet-health awareness, among other factors, influence an individual's Healthy Eating Index (HEI), USDA's measure of overall diet quality. This is the first study that rigorously attempts to examine variation in the index across population groups by controlling for personal and household characteristics and nutrition information levels, as well as test for the endogeneity of nutrition information. Results indicate that one's level of nutrition information has an important influence on one's HEI and that nutrition information and the HEI are simultaneously determined. Other factors explaining variations in HEI's across individuals are income and education levels, race, ethnicity, and age. Evidence supports the hypothesis that higher education promotes more healthful food choices through better acquisition and use of health information.diet quality, Healthy Eating Index, nutrient demand, nutrition knowledge, health inputs, health production, Food Consumption/Nutrition/Food Safety,

    Water in opal – what can it tell us?

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    Opal is a hydrous silica composed of predominantly silicon dioxide and water. The chemical composition of opal is normally described by the general formula SiO2.nH2O. The formula indicates that opal contains water and the value of ‘n’ is variable so the water content is variable and is known to range widely. Such a simple formula hides much of the important characteristics of how water is contained in opal and the variability in the water content and states of water is intricately involved in the formation of opal and may influence properties of the opal as a gemstone. The understanding of the states of water in opal is therefore of importance. The way in which the water is contained provides clues to the mechanisms of formation of opal. The water contained may also be used as a probe to help elucidate the complex microstructure beyond the sphere array structure in which precious opal, in particular, is described. This article will outline the types of water present in opal that displays play-of colour (POC) and how these types have been determined using chemical and physical laboratory characterisation techniques

    Tensin1 expression and function in chronic obstructive pulmonary disease

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    open access articleChronic obstructive pulmonary disease (COPD) constitutes a major cause of morbidity and mortality. Genome wide association studies have shown significant associations between airflow obstruction or COPD with a non-synonymous SNP in the TNS1 gene, which encodes tensin1. However, the expression, cellular distribution and function of tensin1 in human airway tissue and cells are unknown. We therefore examined these characteristics in tissue and cells from controls and people with COPD or asthma. Airway tissue was immunostained for tensin1. Tensin1 expression in cultured human airway smooth muscle cells (HASMCs) was evaluated using qRT-PCR, western blotting and immunofluorescent staining. siRNAs were used to downregulate tensin1 expression. Tensin1 expression was increased in the airway smooth muscle and lamina propria in COPD tissue, but not asthma, when compared to controls. Tensin1 was expressed in HASMCs and upregulated by TGFβ1. TGFβ1 and fibronectin increased the localisation of tensin1 to fibrillar adhesions. Tensin1 and α-smooth muscle actin (αSMA) were strongly co-localised, and tensin1 depletion in HASMCs attenuated both αSMA expression and contraction of collagen gels. In summary, tensin1 expression is increased in COPD airways, and may promote airway obstruction by enhancing the expression of contractile proteins and their localisation to stress fibres in HASMCs

    Tomographic imaging and scanning thermal microscopy: thermal impedance tomography

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    The application of tomographic imaging techniques developed for medical applications to the data provided by the scanning thermal microscope will give access to true three-dimensional information on the thermal properties of materials on a mm length scale. In principle, the technique involves calculating and inverting a sensitivity matrix for a uniform isotropic material, collecting ordered data at several modulation frequencies, and multiplying the inverse of the matrix with the data vector. In practice, inversion of the matrix in impractical, and a novel iterative technique is used. Examples from both simulated and real data are given

    Syntheses, structures, and infrared spectra of the hexa(cyanido) complexes of silicon, germanium, and tin

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    The rare octahedral EC6 coordination skeleton type is unknown for complexes with coordination centers consisting of group 14 elements. Here, the first examples of such EC6 species, the hexacoordinate homoleptic cyanido complexes E(CN)62–, E = Si, Ge, Sn, have been synthesized from element halides SiCl4, GeCl4 and SnF4 and isolated as salts with PPN counterions (PPN+ = (Ph3P)2N+) on a scale of 0.2–1 g. Characterization by spectroscopic techniques and by structure determination through single crystal crystallographic methods show that these pseudohalogen complexes have effective octahedral symmetry in solution and in the solid state. Infrared spectra obtained in solution reveal that the T1u symmetric IR-active vibrations in all three complexes have unusually small oscillator strengths. The observed reluctance of Si(CN)62–, Ge(CN)62–, and Sn(CN)62– to form from chloro-precursors was rationalized in terms of Gibbs free energies, which were found by ab initio calculations at the CCSD(T)-F12b/aug-cc-pVTZ(-PP)-F12 level of theory to be small or even positive. The work demonstrates that E(CN)62– complexes of silicon, germanium and tin are in fact stable at room temperature and exist as well-defined units in the presence of noncoordinating counterions. The results add to our understanding of the chemistry of pseudohalogens and structure and bonding

    Go-stimuli proportion influences response strategy in a sustained attention to response task

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    The sustained attention to response task (SART) usefulness as a measure of sustained attention has been questioned. The SART may instead be a better measure of other psychological processes and could prove useful in understanding some real-world behaviours. Thirty participants completed four Go/No-Go response tasks much like the SART, with Go-stimuli proportions of .50, .65, .80 and .95. As Go-stimuli proportion increased, reaction times decreased while both commission errors and self-reported task-related thoughts increased. Performance measures were associated with task-related thoughts but not taskunrelated thoughts. Instead of faster reaction times and increased commission errors being due to absentmindedness or perceptual decoupling from the task, the results suggested participants made use of two competing response strategies, in line with a response strategy or response inhibition perspective of SART performance. Interestingly, performance measures changed in a nonlinear manner, despite the linear Go proportion increase. A threshold may exist where the prepotent motor response becomes more pronounced, leading to the disproportionate increase in response speed and commission errors. This research has implications for researchers looking to employ the SAR

    Engagement of people with multiple sclerosis to enhance research into the physiological effect of hyperbaric oxygen therapy

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    BACKGROUND: Thousands of people with multiple sclerosis (MS) have used self-administered oxygen therapy in the UK. Clinical trials have been performed, with scant evidence that people with MS have been consulted to explore how they benefit from or how to optimize this treatment. The conventional MS disease disability scores used in trials seldom reflect the effects individuals report when using oxygen therapy to treat their symptoms. METHODS: Three people with MS and the manager of an MS Centre formed a public involvement group and collaborated with clinicians and scientists to inform a lab-based study to investigate the physiological effects of oxygen therapy on microvascular brain endothelial cells. RESULTS: People with MS often use oxygen therapy at a later stage when their symptoms worsen and only after using other treatments. The frequency of oxygen therapy sessions and hyperbaric pressure is individualized and varies for people with MS. Despite direct comparisons of efficacy proving difficult, most individuals are exposed to 100% O2 at 1.5 atmosphere absolute (ATA; 1140 mmHg absolute) for 60 min. In a laboratory-based study human brain endothelial cells were exposed in vitro to 152 mmHg O2 for 60 min with and without pressure, as this equates to 20% O2 achievable via hyperbarics, which was then replicated at atmospheric pressure. A significant reduction in endothelial cells ICAM-1 (CD54) implicated in inflammatory cell margination across the blood brain barrier was observed under oxygen treatment. CONCLUSIONS: By collaborating with people living with MS, we were able to design laboratory-based experimental protocols that replicate their treatment regimens to advance our understanding of the physiological effects of hyperbaric oxygen treatment on brain cells and their role in neuroinflammation
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