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991.
We have developed an enzyme immunoassay (EIA) to quantify trace amounts of ginsenoside Rf (Rf), one of the glycosides of protopanaxatriol from Panax ginseng. A carrier protein of bovine serum albumin (BSA) was coupled to the carbohydrate component of Rf using the periodate oxidation method. Antibodies were raised in rabbits using Rf-BSA conjugate as the immunogen and competitive indirect EIA was used for the determination of Rf. The working range was 0.01-10 ng per assay. The anti-Rf antiserum cross-reacted with ginsenoside Rg2 (105%), which is also a component of Panax ginseng and has a very similar chemical structure to Rf. These results suggest that the anti-Rf antiserum could also be used for the quantitation of ginsenoside Rg2 as well as ginsenoside Rf. In a comparison of EIA and HPLC the linear regression equation and correlation coefficient for the two methods were y(EIA) = 1.31x (HPLC)-11.48 and 0.98, respectively.  相似文献   
992.
Durability Evaluation in the automotive engineering – from theory to product The procedures for durability evaluation in the automotive engineering are represented, especially the methods, load assumption, fatigue testing and the regulations for the release and quality control. By practical examples of the vehicle development from chassis, aggregate and body the procedure is described, in particular the used experimental and virtual simulation methods  相似文献   
993.
The selective catalytic reduction (SCR) of NOx by urea as a reducing agent was carried out over fresh and sulfated CuO/γ‐Al2O3 catalysts in a fluidized‐bed reactor. The optimum temperature ranges for NO reduction on the fresh and sulfated CuO/γ‐Al2O3 catalysts were 300–350 °C and 400–450 °C, respectively. NO reduction with the sulfated CuO/γ‐Al2O3 catalyst was somewhat higher than that with the fresh CuO/γ‐Al2O3 catalyst. N2O formation increased with increasing reaction temperature. Ammonia (NH3) slip increased with increasing gas velocity and decreased with increasing reaction temperature. Copyright © 2003 Society of Chemical Industry  相似文献   
994.
We propose a rigorous 2D approximation technique for the 3D waveguide structures; it can minimize the well‐known approximation errors of the commonly used effective index method. The main concept of the proposed technique is to compensate for the effective cladding index in the equivalent slab model of the original channel waveguide from the modal effective index calculated by the nonuniform 2D finite difference method. With simulations, we used the proposed technique to calculate the coupling characteristics of a directional coupler by the 2D beam propagation method, and the results were almost exactly the same as the results calculated by the 3D beam propagation method.  相似文献   
995.
Electronic textiles: A platform for pervasive computing   总被引:6,自引:0,他引:6  
The invention of the Jacquard weaving machine led to the concept of a stored "program" and "mechanized" binary information processing. This development served as the inspiration for C. Babbage's analytical engine-the precursor to the modern-day computer. Today, more than 200 years later, the link between textiles and computing is more realistic than ever. In this paper, we look at the synergistic relationship between textiles and computing and identify the need for their "integration" using tools provided by an emerging new field of research that combines the strengths and capabilities of electronics and textiles into one: electronic textiles, or e-textiles. E-textiles, also called smart fabrics, have not only "wearable" capabilities like any other garment, but also have local monitoring and computation, as well as wireless communication capabilities. Sensors and simple computational elements are embedded in e-textiles, as well as built into yarns, with the goal of gathering sensitive information, monitoring vital statistics, and sending them remotely (possibly over a wireless channel) for further processing. The paper provides an overview of existing efforts and associated challenges in this area, while describing possible venues and opportunities for future research.  相似文献   
996.
Improved HBT linearity with a "post-distortion"-type collector linearizer   总被引:1,自引:0,他引:1  
An HBT amplifier with a "post-distortion"-type linearizer utilizing a base-collector junction diode shows more than 8-dB improvement of adjacent channel power ratio, and the collector linearizer comprising a reverse biased base-collector junction diode requires no additional dc power consumption and has no deterioration of RF performance. The linearization technique of post-distortion compensates the nonlinearity of HBTs, which arises from the C/sub bc/ variation due to a large-signal swing.  相似文献   
997.
We investigated whether an aqueous extract of Asparagus cochinchinensis Merrill (Liliaceae) roots (ACAE) inhibits secretion of tumor necrosis factor-alpha (TNF-alpha) from primary cultures of mouse astrocytes. ACAE dose-dependently inhibited the TNF-alpha secretion by astrocytes stimulated with substance P (SP) and lipopolysaccharide (LPS). IL-1 has been shown to elevate TNF-alpha secretion from LPS-stimulated astrocytes while having no effect on astrocytes in the absence of LPS. We therefore investigated whether IL-1 mediated inhibition of TNF-alpha secretion from astrocytes by ACAE. Treatment of ACAE to astrocytes stimulated with both LPS and SP decreased IL-1 secretion. Moreover, incubation of astrocytes with IL-1 antibody abolished the synergistic cooperative effect of LPS and SP. These results suggest that ACAE may inhibit TNF-alpha secretion by inhibiting IL-1 secretion and that ACAE has a antiinflammatory activity in the central nervous system.  相似文献   
998.
Glutamic acid decarboxylase (GAD) has been defined as a major target antigen in insulin-dependent diabetes mellitus (IDDM). To identify the molecular ligands triggering a T cell response to GAD, a panel of human GAD65-specific T lymphocyte lines was generated from peripheral blood of three recent onset IDDM patients. All lines derived from a patient expressing the high-risk-conferring HLA-DR*0301/ *0401 haplotypes recognized a single epitope localized between amino acid positions 270 and 283 of GAD65, a stretch that is located in close proximity to the homology region shared with Coxsackie virus P2-C protein. All lines with this specificity were restricted to the DRA, B1*0401 product of the DR4 haplotype. Analysis of the GAD-specific T cell response in a second patient homozygous for DR4 haplotypes demonstrated that the same DRA, B1*0401 allele selected T cells specific for a different determinant. The T cell response profile in a third patient showed that DR*1501/ *1601-encoding haplotypes could present at least three different epitopes to GAD65-specific T lymphocytes. One of these epitopes was presented by a DR allele associated with the resistance-conferring DRB1*1501 haplotype. GAD-specific T cell lines could not be isolated from HLA class II-matched normal individuals. Our data reveal that (a) the T cell response to GAD65 is quite heterogenous in recent onset IDDM patients; (b) HLA-DR, not DQ, seems to be the principal restriction element used by T cells present at the onset of the disease; and (c) T cells responding to epitopes containing identical sequences to Coxsackie virus P2-C protein were not detected.  相似文献   
999.
The appropriateness of the task complexity (TACOM) measure that can quantify the complexity of procedural tasks was validated in this study. To this end, two sets of task performance time data that have been extracted under the simulated steam generator tube rupture (SGTR) conditions of the reference nuclear power plant (NPP) A and B were compared with the associated TACOM scores. As a result, it was observed that two sets of task performance time data seem to be soundly explained by the associated TACOM scores. Although more additional activities should be conducted to clarify the appropriateness of the TACOM measure, the result of this study provides a crucial clue supporting that the complexity of emergency tasks stipulated in emergency operating procedures (EOPs) can be properly quantified by the TACOM measure.  相似文献   
1000.
A defuzzification method is an important performance factor in fuzzy logic controllers (FLCs). When an FLC uses multishaped output fuzzy sets, existing defuzzification methods have the fat shape dominance phenomenon. The authors propose a new defuzzification method for multishaped output fuzzy sets. The method takes the degree of certainty on the fired level into account in the defuzzification process. Simulation experiments with a nonlinear plant show that an FLC employing the proposed defuzzification method is more stable and robust than existing FLCs  相似文献   
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