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Mixing is a mechanical operation to distribute components evenly in a plane or a space. Composite molding and textile manufacturing industries are routinely taking advantage of mixing operations in order to distribute raw materials uniformly or in a specific way during composite molding or textile producing processes. Key issues to identify any mixed state are (1) the time needed to accomplish through mixing (the time scale) and (2) the extent of the homogeneity of the mixture in a plane (the length scale). In this paper, a new concept of mixture status is focused on the length scale. The goal to derive a new concept of mixture status is to establish a measure to describe the mixed extent of a mixture consisting of two components, derived from clump size and clump distribution. To verify the usefulness of the newly conceived “Mixedness Index”, the suggested definition was compared with the existing coefficient of variation (CV) method based on simulation and experiments. Results showed a reasonable relationship between the Mixedness Index and observation, demonstrating the feasibility of the proposed Mixedness Index for industrial applications.  相似文献   
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Class I major histocompatibility complex (class I MHC) molecules, known to be important for immune responses to antigen, are expressed also by neurons that undergo activity-dependent, long-term structural and synaptic modifications. Here, we show that in mice genetically deficient for cell surface class I MHC or for a class I MHC receptor component, CD3zeta, refinement of connections between retina and central targets during development is incomplete. In the hippocampus of adult mutants, N-methyl-D-aspartate receptor-dependent long-term potentiation (LTP) is enhanced, and long-term depression (LTD) is absent. Specific class I MHC messenger RNAs are expressed by distinct mosaics of neurons, reflecting a potential for diverse neuronal functions. These results demonstrate an important role for these molecules in the activity-dependent remodeling and plasticity of connections in the developing and mature mammalian central nervous system (CNS).  相似文献   
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Campylobacter jejuni is one of the major causative pathogens of outbreaks or sporadic cases of diarrhoeal diseases worldwide. In this study, we compared the phenotypic and genetic characteristics of C. jejuni isolates of human and food‐producing animal origins in Korea and examined the genetic relatedness between these two groups of isolates. Regardless of isolation source, all C. jejuni isolates harboured four virulence genes, cadF, cdtB, ciaB and racR, whereas the wlaN and virB11 genes were more frequently observed in human isolates. Antimicrobial susceptibility testing showed that the majority of C. jejuni isolates displayed high‐level resistance to fluoroquinolone (95.2%) or tetracycline (76.2%) antibiotics, and 12.4% of isolates exhibited multidrug resistance (more than three classes of antibiotics tested). Pulsed‐field gel electrophoresis (PFGE) of all Campylobacter isolates revealed 51 different SmaI‐PFGE patterns and six major clusters containing both human and animal isolates. These results indicate that genetically diverse strains of C. jejuni with antimicrobial drug‐resistance and virulence properties have prevailed in Incheon. Nevertheless, some particular populations continue to circulate within the community, providing the evidence for an epidemiological link of C. jejuni infections between humans and food‐producing animals. Therefore, the continued monitoring and surveillance of C. jejuni isolates of human and food‐producing animal origins are required for public health and food safety.  相似文献   
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The dynamics of the friction yarn formation process is described in terms of the dynamic behavior of the process state variables. Production efficiency and product quality of friction spinning are influenced by these process state variables. This study was performed with the intention of setting up a dynamic model based on mass balance in order to delineate the dynamic behavior of the cross-sectional area of the in-process bundle on the friction drum surface and to attain the distribution profiles of the cross-sectional area in transient state and in steady state as well. Then, simulation results were compared with those of the experiment, while the input variation was used as a test signal. Theoretical model shows that the bundle thickness on the friction drum has the dynamic characteristics of an integrating system with interval due to the finite length of the input fleece zone, and is in good correspondence with the results of the experiment. A periodic change in the fleece feeding rate led to the fact that there was a specific range of the fluctuation wavelength in the fleece feeding rate, whereas a change in the in-process bundle thickness completely disappeared or became locally maximized in certain wavelength areas. This could lead to a magnification or inaction of the perturbations with the corresponding wavelength in the bundle thickness; a bundle thickness irregularity. Experiments also identified that the theoretical model accurately described the fiber accumulation dynamics in a friction spinning process.  相似文献   
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An 8-year-old, spayed, female poodle presented with exercise intolerance, lethargy, respiratory distress, retching, hyporexia and diarrhoea. Thoracic radiographs revealed increased opacity in the left cranial thoracic region. The fifth and sixth ribs appeared to be bulging cranially to caudally, and CT and surgical exploration confirmed the presence of a thoracic wall defect in that area. CT showed abrupt occlusion of the bronchus that branches into the left cranial lobe and consolidation of the caudal segment of left cranial lung lobe, which led to the diagnosis of lung lobe torsion. A thoracotomy was performed, the twisted lung lobe was surgically excised, and the defect in the thoracic wall was repaired. Respiratory distress gradually improved after the surgery, and there were no identified complications within the 2-year period following the procedure. Based on our literature search, this is the first reported case of lung lobe torsion caused by a thoracic wall defect in a dog.  相似文献   
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An herbal extract mixture and yogurt added to the herbal extract mixture were tested for their protective and therapeutic effects on ethanol-induced liver injury. The herbal extract mixture, yogurt and commercial drugs were used for treatment for two weeks prior to administering a single oral dose of ethanol (3 g/kg body weight). The herbal extract mixture and yogurt added to the herbal extract mixture were found to provide protection against ethanol-induced toxicity comparable to the commercial drug treatment, according to the serum and histopathological analysis. It was also shown that co-treatment with herbal extract mixture and yogurt against a triple oral dose of ethanol (2 g/kg body weight, over one week) provided protection against ethanol toxicity. After the initial set of experiments, the herbal extract mixture and yogurt treatments were extended for three more weeks. When compared to the positive control, further treatment with both the herbal extract and yogurt significantly reduced liver injury and resulted in a lower grade of lipid deposition.  相似文献   
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The surface evenness and texture are closely related with the irregularity of yarn thickness. Besides, yarn thickness variation has an important role to influence the yarn performance and the textile process efficiency. Thus, the information not only on the yarn thickness, but also on the short- term irregular characteristics that have not been known before is required for enhancing the qualities of textile products. This paper reports the results of a study about the yarn thickness and its variation for various types of yarn on the basis of a new measurement system applying a laser slit beam as a light source. The new method delivers effective information on the irregularity. The analysis of the measured signal confirms that the visual shade created by the yarn doubling and twisting can be measured and the yarn thickness characteristics can be represented by correlograms. Depending on yarn types, correlograms have different shapes and can be approximated to an exponentially decaying function with or without fluctuating magnitude. In addition, the effective information on the yarn irregularity can be influenced by the sampling length interval of the measuring device used for tests.  相似文献   
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