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Polyphenols are bioactive compounds found naturally in fruits and vegetables; they are widely used in disease prevention and health maintenance. Polyphenol-rich blackcurrant extract (BCE) exerts beneficial effects on vascular health in menopausal model animals. However, the vasculoprotective effects in diabetes mellitus (DM) and atherosclerotic vascular disease secondary to DM are unknown. Therefore, we investigated whether BCE is effective in preventing atherosclerosis using KK-Ay mice as a diabetes model. The mice were divided into three groups and fed a high-fat diet supplemented with 1% BCE (BCE1), 3% BCE (BCE2), or Control for 9 weeks. The mice in the BCE2 group showed a considerable reduction in the disturbance of elastic lamina, foam cell formation, and vascular remodeling compared to those in the BCE1 and Control groups. Immunohistochemical staining indicated that the score of endothelial nitric oxide synthase staining intensity was significantly higher in both BCE2 (2.9) and BCE1 (1.9) compared to that in the Control (1.1). Furthermore, the score for the percentage of alpha-smooth muscle actin was significantly lower in the BCE2 (2.9%) than in the Control (2.1%). Our results suggest that the intake of anthocyanin-rich BCE could have beneficial effects on the blood vessels of diabetic patients.  相似文献   
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The rate and extent of uptake and release of moisture are critical in controlling the behavior of cementitious materials ranging from fluid transport to hygral deformations. While classically determined using an equilibrium (static) salt solution method (Baroghel-Bouny in Cem Concr Res 37:414–437, 2007), advanced capabilities offered by gravimetric dynamic vapor sorption (DVS) analyzers, are now permitting acquisition of sorption spectra at microgram ( $\upmu \hbox {g}$ ) resolution on the order of a few weeks. This work highlights new multicycle determinations of adsorption/desorption isotherms, acquired using a custom-built DVS analyzer for well-hydrated alite and ordinary portland cement pastes over a range of water-to-solid ratios ( $w/s$ , mass basis). Special focus is paid to describe measurement aspects relevant to acquiring reliable spectra, and their interpretation. Sorption isotherms are used to assess transport properties, and sorption hysteresis and its irreversibility following first drying. Based on an optimization-based criterion, the Young-Nelson model is selected to simulate sorption evolutions, including the effects of hysteresis. Sensitivity analyses carried out using this model are used to understand the role of parameters, including porosity and $w/s$ , on the hysteresis that develops from the first to subsequent sorption cycles.  相似文献   
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Near-field acoustical holography (NAH) is a useful tool for the identification and visualization of vibro-acoustic sources. In particular, NAH can be applied to many practical sources having irregular shape if the inverse boundary element method (BEM) is employed. Once the relation between the source and the radiated field is defined in the transfer matrix modeled by the BEM, the reconstruction of acoustic parameters on the source surface can be conducted by the multiplication of the inverse transfer matrix and the field data measured over the hologram surface. The usual practical way to measure the field data radiated from an irregular shaped source is to adopt a regular hologram surface, which can be a flat, cylindrical, or spherical shape, for the measurement ease. Then, the hologram surface is not conformal to the source surface and the resulting transfer matrix becomes further ill-posed than the conformal case. To investigate the effect of sensor proximity and distance variability on the reconstruction error, simulation and measurement were conducted for an interior problem comprised of a parallelepiped rigid box with a vibrating end plate. Flat, tilted, and randomized hologram surfaces were adopted in the test. It was shown that the reconstruction error is greatly affected by the conditioning of transfer matrix which is related to the positioning of sensor. To improve the reconstruction accuracy, an investigation was conducted to find proper field points among a large number of overdetermined field points. The number of field data was reduced gradually under various reduction schemes using condition number, effective independence value, and sensor distance. It was demonstrated that the quality of reconstruction result given by the non-conformal measurement can be improved by removing some field points that contribute to the ill-conditioning of the inverse problem. A small improvement of the reconstruction accuracy was observed by reducing the field points in the overdetermined situation. However, further reduction of the field points, becoming an underdetermined situation, yielded a drastic improvement of the reconstruction accuracy.  相似文献   
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Electrokinetics can be utilized to solve many problems in geotechnical and environmental engineering. The processes which occur in association with electrokinetics are complicated and difficult to control. The success of the application depends on certain conditions which are controlled by many parameters. It is therefore important to understand these processes so that methods and procedures can be optimized. In this paper theoretical considerations, results of tests and examples of in situ applications are presented and discussed. The presented examples show ways of controlling and improving the efficiency of electrokinetic processes.  相似文献   
5.
When heating vinyl polymers within the temperature gradient of 50–450° C, they are fragmented in certain temperature ranges to defined products. These products are fractionated on the TLC-layer and subsequently chromatographed. Based on the thermofractograms obtained identification of the starting material can be made. From polyvinyl esters, e.g., the corresponding acid is obtained and copolymers yield the different acids. Thermolysis of polyvinyl carbazole yields vinyl carbazole and vinyl pyrrolidone and pyrrolidone are obtained from polyvinyl pyrrolidone. Polymethacrylate is fragmented to the corresponding methacrylate, and acrylate if obtained from polyacrylate. Evaluation of the thermofractograms leads in part to new conceptions about structures and cleavage mechanisms of such polymers.  相似文献   
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