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An immunochromatographic assay (ICA) strip is one of the most widely used platforms in the field of point-of-care biosensors for the detection of various analytes in a simple, fast, and inexpensive manner. Currently, several approaches for sequential reactions in ICA platforms have improved their usability, sensitivity, and versatility. In this study, a new, simple, and low-cost approach using automatic sequential-reaction ICA strip is described. The automatic switching of a reagent pad from separation to attachment to the test membrane was achieved using a water-swellable polymer. The reagent pad was dried with an enzyme substrate for signal generation or with signal-enhancing materials. The strip design and system operation were confirmed by the characterization of the raw materials and flow analysis. We demonstrated the operation of the proposed sensor by using various chemical reaction-based assays, including metal-ion amplification, enzyme-colorimetric reaction, and enzyme-catalyzed chemiluminescence. Furthermore, by employing C-reactive protein as a model, we successfully demonstrated that the new water-swellable polymer-based ICA sensor can be utilized to detect biologically relevant analytes in human serum.
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We use persistent homology to build a quantitative understanding of large complex systems that are driven far-from-equilibrium. In particular, we analyze image time series of flow field patterns from numerical simulations of two important problems in fluid dynamics: Kolmogorov flow and Rayleigh–Bénard convection. For each image we compute a persistence diagram to yield a reduced description of the flow field; by applying different metrics to the space of persistence diagrams, we relate characteristic features in persistence diagrams to the geometry of the corresponding flow patterns. We also examine the dynamics of the flow patterns by a second application of persistent homology to the time series of persistence diagrams. We demonstrate that persistent homology provides an effective method both for quotienting out symmetries in families of solutions and for identifying multiscale recurrent dynamics. Our approach is quite general and it is anticipated to be applicable to a broad range of open problems exhibiting complex spatio-temporal behavior.
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A new insect species (†Alienopterus brachyelytrus Bai, Beutel, Klass, Wipfler et Zhang gen. et sp. nov.) of a new order and family is described, based on a single male embedded in Cretaceous Burmese amber (ca. 99Ma). Unusual characters are shortened forewings combined with fully developed, operational hindwings, similar as in Dermaptera, and specialized attachment pads otherwise only found in mantophasmatodeans (heelwalkers). A cladistic analysis suggests a placement as sister to Mantodea, supported by a profemoral brush and other characters. The male genitalia show the same pattern in both groups. Specialized features are the unusual flight apparatus, attachment structures adapted for locomotion on leaves, and a dense profemoral setation suitable for catching small prey. †Alienopterus was apparently able to fly and likely a predator of small arthropods in bushes or trees. An impressive radiation of Mantodea started in similar habitats at least 35Ma later in the early Cenozoic. In contrast, †Alienopterus was an evolutionary dead end in the roach–mantis transition zone.
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This paper proposes a new material efficient process for producing lightweight tubular screws and nuts. The process is built on the fundamentals of tube end forming and combines tube reduction, expansion, flaring and compression beading to establish two multi-stage cold forming sequences for producing hexagon head tubular screws and nuts. The methodology draws from the mechanical characterization of the material to the design and fabrication of an experimental apparatus consisting of several individual die sets. The investigation is supported by finite element modelling and it is aimed at evaluating the major process parameters, the overall feasibility of the process and the required forming loads.
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The MITICA experiment (Megavolt ITER Injector & Concept Advancement) is the prototype and the test bed of the Heating and Current Drive Neutral Beam Injectors, which will be necessary for the full-performance exploitation of ITER. MITICA injector experiments shall demonstrate the reliable and accurate emission of a 17 MW beam of neutral particles for duration up to 1 hour, fulfilling ITER specific requirements.
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A simple, one-step method has been developed to construct a corrosion-resistant bionic superhydrophobic surfaces by solve-thermal process in an ethanol and water solution containing stearic acid. Superhydrophobic surface with biomimetic micronanostructures was prepared in this study. The Mammillaria herrerae-like microspheres, carnation-like microclusters and carnation-petal-like nanoslices of biomimetic micronanostructures on magnesium alloy surface can create a stable superhydrophobic surface, which is similar to the “lotus leaf” structure. The as-prepared superhydrophobic surface had a contact angle of 158.5° and a sliding angle of 2.0°. The as-prepared superhydrophobic surfaces were characterized by means of scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD) and contact angle measurement. Potentiodynamic polarization measurements demonstrated that the superhydrophobic surface greatly improved the corrosion properties of magnesium alloy in 3.5wt% NaCl solution.
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The capacity to use language to form new representations and to revise existing knowledge is a crucial aspect of human cognition. Here we examined whether infants can use language to adjust their representation of a recently encoded scene. Using an eye-tracking paradigm, we asked whether 16-month-old infants (N=26; mean age=16;0 [months;days], range=14;15–17;15) can use language about an occluded event to inform their expectation about what the world will look like when the occluder is removed. We compared looking time to outcome scenes that matched the language input with looking time to those that did not. Infants looked significantly longer at the event outcome when the outcome did not match the language input, suggesting that they generated an expectation of the outcome based on that input alone. This effect was unrelated to infants’ vocabulary size. Thus, using language to adjust expectations about the visual world is present at an early developmental stage even when language skills are rudimentary.
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Design and lifetime prediction of structural and mechanical components require the assessment of the global probability of failure to be determined from stress and strain distributions obtained by FEM, as well as calculation of hazard maps in order to facilitate redesign and recognition of critical parts to be inspected regularly. The so-called generalized probabilistic local approach (GPLA), developed by the authors, allows the primary failure cumulative distribution function (PFCDF) owning to a certain failure type to be determined for a given material from experimental data and used subsequently for probabilistic design. The approach ensures a realistic safety margin provided that the failure criterion represented by an adequate generalized parameter (GP) and the corresponding failure criterion is properly recognized as a reference variable to be considered in the failure assessment. The way in which the results of such a reliability analysis are interpreted encompasses a variety of concepts under which failure can be understood and may be classified as global probability of failure and hazard maps, the former providing the conclusive failure probability for definitive design, and the latter representing, presumably, a risk of local failure that facilitates the possible component redesign but without providing the global probability of failure. In order to promote the implementation of the methodology proposed, an application is exemplary presented for the particular case of experimental results of glass plates. A finite element subroutine is developed for calculation of hazard maps and global probabilities of failure.
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Cannabinoid CB2 receptors (CB2Rs) are emerging as important therapeutic targets in brain disorders that typically involve neurometabolic alterations. We here addressed the possible role of CB2Rs in the regulation of glucose uptake in the mouse brain. To that aim, we have undertaken 1) measurement of 3H-deoxyglucose uptake in cultured cortical astrocytes and neurons and in acute hippocampal slices; 2) real-time visualization of fluorescently labeled deoxyglucose uptake in superfused hippocampal slices; and 3) in vivo PET imaging of cerebral 18F-fluorodeoxyglucose uptake. We now show that both selective (JWH133 and GP1a) as well as non-selective (WIN55212-2) CB2R agonists, but not the CB1R-selective agonist, ACEA, stimulate glucose uptake, in a manner that is sensitive to the CB2R-selective antagonist, AM630. Glucose uptake is stimulated in astrocytes and neurons in culture, in acute hippocampal slices, in different brain areas of young adult male C57Bl/6j and CD-1 mice, as well as in middle-aged C57Bl/6j mice. Among the endocannabinoid metabolizing enzymes, the selective inhibition of COX-2, rather than that of FAAH, MAGL or α,βDH6/12, also stimulates the uptake of glucose in hippocampal slices of middle-aged mice, an effect that was again prevented by AM630. However, we found the levels of the endocannabinoid, anandamide reduced in the hippocampus of TgAPP-2576 mice (a model of β-amyloidosis), and likely as a consequence, COX-2 inhibition failed to stimulate glucose uptake in these mice. Together, these results reveal a novel general glucoregulatory role for CB2Rs in the brain, raising therapeutic interest in CB2R agonists as nootropic agents.
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