492 research outputs found

    Investigating the use of the coanda effect to create novel unmanned aerial vehicles.

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    In recent years the demand for Unmanned Aerial Vehicles(UAV's) has increased rapidly across many different industries and they are used for various applications. Such systems have the ability to enter dangerous or inaccessible environments and allow vital information to be collected without human risk. In order to carry out a task, a UAV has to face many different challenges. This has led to the development of novel platforms that move away from traditional aircraft design in order to make them more capable. A good example of this type of craft is one which uses the Coanda Effect to assist propulsion. This effect was discovered in 1930 by Henri-Marie Coanda who found that if a thin film of air is directed over a curved body, then the air follows the curve. When used to propel a UAV, the Coanda Effect also entrains air from above and lowers the air pressure in this region, which in turn generates more lift. Many organizations have attempted to use this phenomenon to aid the lift of various unusual air vehicles

    Topography driven spreading

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    Roughening a hydrophobic surface enhances its nonwetting properties into superhydrophobicity. For liquids other than water, roughness can induce a complete rollup of a droplet. However, topographic effects can also enhance partial wetting by a given liquid into complete wetting to create superwetting. In this work, a model system of spreading droplets of a nonvolatile liquid on surfaces having lithographically produced pillars is used to show that superwetting also modifies the dynamics of spreading. The edge speed-dynamic contact angle relation is shown to obey a simple power law, and such power laws are shown to apply to naturally occurring surfaces

    Human intestinal microbiota composition is associated with local and systemic inflammation in obesity.

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    OBJECTIVE: Intestinal microbiota have been suggested to contribute to development of obesity, but the mechanism remains elusive. We relationship between microbiota composition, intestinal permeability, inflammation in non-obese and obese subjects. DESIGN AND METHODS: Fecal microbiota composition of 28 subjects (BMI 18.6-60.3kg/m2 ) was analyzed phylogenetic profiling microarray. Fecal calprotectin and plasma C- protein levels were determined to evaluate intestinal and systemic Furthermore, HbA1c , and plasma levels of transaminases and lipids were Gastroduodenal, small intestinal, and colonic permeability were assessed multi-saccharide test. RESULTS: Based on microbiota composition, the population segregated into two clusters with predominantly obese (15/19) exclusively non-obese (9/9) subjects. Whereas intestinal permeability differ between clusters, the obese cluster showed reduced bacterial decreased Bacteroidetes/Firmicutes ratio, and an increased abundance of pro-inflammatory Proteobacteria. Interestingly, fecal calprotectin was detectable in subjects within the obese microbiota cluster (n=8/19, Plasma C-reactive protein was also increased in these subjects correlated with the Bacteroidetes/Firmicutes ratio (rs =-0.41, p=0.03). CONCLUSIONS: Intestinal microbiota alterations in obese subjects are with local and systemic inflammation, suggesting that the obesity- microbiota composition has a pro-inflammatory effect

    Multiple Orbitoides d’Orbigny lineages in the Maastrichtian? Data from the Central Sakarya Basin (Turkey) and Arabian Platform successions (Southeastern Turkey and Oman)

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    The standard reconstruction of species of Orbitoides d’Orbigny into a single lineage during the late Santonian to the end of the Maastrichtian is based upon morphometric data from Western Europe. An irreversible increase in the size of the embryonic apparatus, and the formation of a greater number of epi-embryonic chamberlets (EPC) with time, is regarded as the main evolutionary trends used in species discrimination. However, data from Maastrichtian Orbitoides assemblages from Central Turkey and the Arabian Platform margin (Southeastern Turkey and Oman) are not consistent with this record. The Maastrichtian Besni Formation of the Arabian Platform margin in Southeastern Turkey yields invariably biconvex specimens, with small, tri- to quadrilocular embryons and a small number of EPC, comparable to late Campanian Orbitoides medius (d’Archiac). The upper Maastrichtian Taraklı Formation from the Sakarya Basin of Central Turkey contains two distinct, yet closely associated forms of Orbitoides, easily differentiated by both external and internal features. Flat to biconcave specimens possess a small, tri- to quadrilocular embryonic apparatus of Orbitoides medius-type and a small number of EPC, whereas biconvex specimens possess a large, predominantly bilocular embryonic apparatus, and were assigned to Orbitoides ex. interc. gruenbachensis Papp–apiculatus Schlumberger based on morphometry. The flat to biconcave specimens belong to a long overlooked species Orbitoides pamiri Meriç, originally described from the late Maastrichtian of the Tauride Mountains in SW Turkey. This species is herein interpreted to be an offshoot from the main Orbitoides lineage during the Maastrichtian, as are forms that we term Orbitoides ‘medius’, since they recall this species, yet are younger than normal occurrence with the accepted morphometrically defined lineage. The consistent correlation between the external and internal test features in O. pamiri implies that the shape of the test is not an ecophenotypic variation, but appears to be biologically controlled. We, therefore, postulate that more than one lineage of Orbitoides exists during the Maastrichtian, with a lineage that includes O. ‘medius’ and O. pamiri displaying retrograde evolutionary features

    A Common Network of Functional Areas for Attention and Eye Movements

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    AbstractFunctional magnetic resonance imaging (fMRI) and surface-based representations of brain activity were used to compare the functional anatomy of two tasks, one involving covert shifts of attention to peripheral visual stimuli, the other involving both attentional and saccadic shifts to the same stimuli. Overlapping regional networks in parietal, frontal, and temporal lobes were active in both tasks. This anatomical overlap is consistent with the hypothesis that attentional and oculomotor processes are tightly integrated at the neural level

    Comparison of the efficacy of once- and twice-daily colchicine dosage in pediatric patients with familial Mediterranean fever - a randomized controlled noninferiority trial

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    Background: In this study, we examined the efficacy and safety of a once-daily dosage schema of colchicine compared with a twice-daily dosage schema in pediatric patients with familial Mediterranean fever (FMF). Methods: In this 24-week, multicenter, randomized controlled noninferiority trial, pediatric patients newly diagnosed with FMF carrying a homozygous or compound heterozygous mutation and not receiving any treatment were included. Patients were randomly assigned using a block randomization method to receive treatment with a once- or twice-daily dosage. Clinical and laboratory characteristics and medication side effects were recorded and compared between groups. The study was carried out in compliance with Good Clinical Practice and the Consolidated Standards for Reporting of Trials (CONSORT) statement. Results: A total of 92 patients were selected, and 79 patients completed the study. There were 42 patients in the once-daily dosage group and 37 in the twice-daily dosage group. The results indicated that the once-daily dosage was not inferior to the twice-daily dosage regarding decrease in attack frequency and duration as well as improvement in clinical findings and Mor severity scores. Alterations in laboratory findings indicating inflammation, such as erythrocyte sedimentation rate, C-reactive protein, and serum amyloid A, were similar in both groups. The rates of drug side effects were similar between the once- and twice-daily dosage groups, implying comparable safety of colchicine, with the exception of diarrhea, which was slightly higher in the once-daily dosage group. Conclusions: Using colchicine with either a once- or twice-daily dosage provides similar clinical and laboratory improvements. Considering both efficacy and safety, colchicine can be prescribed with a once-daily dosage. Trial Registration ID: ClinicalTrials.gov identifier NCT02602028. Registered 5 November 2015
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