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1.
Methylglyoxal (MG), an endogenous metabolite that increases in diabetes, is a common intermediate in nonenzymatic glycation (Maillard reaction) in vivo. Here we describe the immunochemical approach to the detection of MG adducts in proteins in vitro and in atherosclerotic lesions of human aorta in vivo. The reaction of protein (bovine serum albumin) with MG led to selective loss of arginine and lysine residues, accompanied by the formation of 5-methylimidazolone (N delta-(5-methylimidazolon-2-yl)ornithine) and imidazolysine (1,3-di-lysino-4-methylimidazole) derivatives, respectively. The anti-5-methylimidazolone antibody was prepared by immunizing rabbits with a MG-keyhole limpet hemocyanin conjugate and purifying the serum on an affinity gel prepared by covalent attachment of the 5-methylimidazolone derivative. The antibody cross-reacted with the proteins treated with not only MG but trioses, such as hydroxyacetone, dihydroxyacetone, and glyceraldehyde. The immunohistochemical analysis revealed that atherosclerotic lesions of human aorta contained 5-methylimidazolone derivatives whose distributions were identical to those of advanced glycation end products (AGEs) detected by the anti-AGE antibody.  相似文献   
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There has been increasing use of Al-Li alloys in the aerospace industry, due mainly to the low density and high elastic modulus of this material. However, the problem of low ductility and fracture toughness of this material has limited its present application to only weight- and stiffness-critical components. Development of Al-Li/ceramic composites is currently being investigated to enhance the service capabilities of this material. The Ti-Al alloy is also of interest to aerospace-type applications, engine components in particular, due to its attractive high-temperature properties. Preparation of fine powders by plasma melting of composite feedstock and coatings formed by plasma spraying was carried out to examine the effect of spray parameters on the microstructure and properties of these materials. Characterization of the powders and coatings was performed using the scanning electron microscope and image analyzer. Examination of the plasma-sprayed powders and coatings has shown that in the Al-Li/SiC composite there is melting of both materials to form a single composite particle. The SiC reinforcement was in the submicron range and contributed to additional strengthening of the composite body, which was formed by a cold isostatic press and consolidated by hot extrusion or hot forging processes. The plasma-sprayed Ti-Al powder showed four categories of microstructures: featureless, dendritic, cellular, and martensite-like.  相似文献   
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The functional properties of Caryodendron orinocense protein product were investigated and compared with those of soybean (Glycina maxima). The product protein content was 24.47 g/100 g (Nx6.25). Solubility increased at both sides of the isoelectric point (pH 4.0) and with increased NaCl concentration up to 0.5M. Compared with soybean flour (50% protein), the protein product exhibited higher water and oil absorption, but lower emulsifying activity, emulsion stability, foaming capacity, and foam stability, the last one increase at higher pH. Emulsifying activity, foaming capacity, and foam stability were ionic strength dependent. C. orinocense protein product increased its emulsifying activity steadily from 0.05M to 0.75M NaCl, while it remained almost constant for soybean flour. Foaming capacity increased drastically at pH 10. The minimum time and concentration to form a gel was 20% in 4 min and 10% in 8 min for the Caryodendron protein product and soybean flour, respectively. The bulk density was 0.5056+/-0.0041 g/mL.  相似文献   
5.
Micro powder injection molding (PIM) is a promising process for low cost fabrication of three-dimensional microstructures. The PIM can be used for a wide range of metal and ceramic materials, combined with the potential for mass production. In this paper, initial study on the molding of 316L stainless steel microstructures was investigated. Three different micro-cavity shapes were used. Small powder with mean size of 4 m was used with two multi-component binder systems. Microstructures with dimension as small as 35 m could be injection molded. For successful molding, the binder system must provide high green strength to withstand ejection from the mold and suitable molding parameters used. For example, a high mold temperature is required and ejection speed must be reduced. The cross-sections of the microstructures are precisely replicated. The general shape in the depth direction is replicated although it is not as good as that for the cross-section. More work has to be conducted to realize the full potentials of the process.The authors would like to thank the Nanyang Technological University for awarding a research grant to conduct this research and Adeka Fine Chemicals (Tokyo) for the supply of PAN 250 binder.  相似文献   
6.
This work proposes a novel approach called stand-alone hybrid system power pinch analysis (SAHPPA), which is particularly applicable for the design of off-grid distributed energy generation systems. The enhanced graphical tool employs new ways of utilising the recently introduced demand composite curve and supply composite curve while honouring and adapting fundamental energy systems engineering concepts. The SAHPPA method is capable of optimising the capacity of both the power generators and energy storage for biomass (i.e. non-intermittent) and solar photovoltaic (i.e. intermittent) energy technologies, which is a contribution to the emerging area of power pinch analysis. In addition, the procedure considers all possible efficiency losses in the overall system encompassing the charging–discharging and current inversion processes.  相似文献   
7.
Abstract

A simplified explicit formula for the displacement bounds of the beam‐column subjected to time‐dependent boundary constraints is proposed. The formula is derived by means of removing time dependence from the boundary conditions. The proposed bounds provide a quick estimation of the displacements for problems with complex loading conditions.  相似文献   
8.
Hydroxyapatite powders were made by reacting orthophosphoric acid with calcium hydroxide and dense bioactive coatings were subsequently produced by the plasma spray technique. Three types of hydroxyapatite (flame spheroidized) monolayer coatings and three types of functionally graded coatings were manufactured. It was found that average microhardness values of monolayer coatings decreased as the indentation load increased. The relationship between indentation load and indent diagonal length observed Meyer's law. Microhardness and fracture toughness of coatings were affected by characteristics of feedstock powders for plasma spraying. The indentation fracture toughness of coatings could be significantly increased by incorporating a toughening phase. ©1999 Kluwer Academic Publishers  相似文献   
9.
The rapid development of computing software has facilitated multifarious research in integrated circuit (IC) packaging. Complicated and complex processes can be visualized via simulation modeling with this software. The applications of aided software enhance the fundamental physicochemical understanding and visualization of the IC encapsulation process. In this article, fluid–structure interaction (FSI) during IC encapsulation through computer-aided simulation is reviewed based on the amount of substantial work conducted from the past decades to the present. FSI phenomena in various IC encapsulations, such as wire sweep, paddle shift, lead frame deformation, IC chip, and through-silicon via (TSV) deformation, is considered in the review. The significance and challenges of FSI analysis are also highlighted in this article.  相似文献   
10.
Information Systems and e-Business Management - Analysing stock financial data and producing an insight into it are not easy tasks for many stock investors, particularly individual investors....  相似文献   
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