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91.
92.
Electrical and optical properties of an argon plasma jet were characterized. In particular, effects of an additive gas, namely nitrogen or oxygen, on these prop...  相似文献   
93.
The yield of genomic DNA extracted from corn-processed foods, such as corn flake and one of the corn snack what is called "Jumbo corn", using an ion-exchange resin type kit (Gtip) has been reported to be very low, and it is thought to be difficult to detect the intrinsic corn gene "Zein" in the foods. Therefore, we developed a new method using Gtip, which we called the "KNG-Gtip method," by modification of the Ministry of Health, Labour and Welfare (MHLW) method using Gtip (MHLW-Gtip method). We compared the KNG-Gtip method, MHLW-Gtip method, the Gtip method for detection of allergen (ALG-Gtip method), and the Gtip method according to the Ministry of Agriculture, Forestry and Fisheries (MAFF) (JAS-Gtip method) in terms of the yield and quality of genomic DNA and the detection probabilities of the PCR-amplified Zein gene. The concentrations of DNA and the detection probabilities of the PCR-amplified Zein gene of genomic DNA extracted from 4 g corn flake and 4 g Jumbo corn by the KNG-Gtip method were larger than those by using the conventional methods. In addition, the PCR-amplified Zein gene from 4 g of corn starch could be detected by the KNG-Gtip method. We propose that the KNG-Gtip method, in which requires sample weight of four grams, is practical and useful to extract genomic DNA from corn flake and Jumbo corn.  相似文献   
94.
The β-site amyloid precursor protein cleaving enzyme 1 (BACE1, also known as β-secretase) is a promising target for the treatment of Alzheimer's disease. A pKa lowering approach over the initial leads was adopted to mitigate hERG inhibition and P-gp efflux, leading to the design of 6-CF3 dihydrothiazine 8 (N-(3-((4S,6S)-2-amino-4-methyl-6-(trifluoromethyl)-5,6-dihydro-4H-1,3-thiazin-4-yl)-4-fluorophenyl)-5-cyanopicolinamide). Optimization of 8 led to the discovery of 15 (N-(3-((4S,6S)-2-amino-4-methyl-6-(trifluoromethyl)-5,6-dihydro-4H-1,3-thiazin-4-yl)-4-fluorophenyl)-5-(fluoromethoxy)pyrazine-2-carboxamide) with an excellent balance of potency, hERG inhibition, P-gp efflux, and metabolic stability. Oral administration of 8 elicited robust Aβ reduction in dog even at 0.16 mg/kg. Reflecting the reduced hERG inhibitory activity, no QTc prolongation was observed at high doses. The potential for reactive metabolite formation of 15 was realized in a nucleophile trapping assay using [14C]-KCN in human liver microsomes. Utilizing covalent binding (CVB) in human hepatocytes and the maximum projected human dosage, the daily CVB burden of 15 was calculated to be at an acceptable value of below 1 mg/day. However, hepatotoxicity was observed when 15 was subjected to a two-week tolerance study in dog, which prevented further evaluation of this compound.  相似文献   
95.
switched beam CDMA系统中小区容量和覆盖半径的计算   总被引:1,自引:0,他引:1  
本文推导了switched beam系统中干扰因子的计算式,以及中断概率、基站接收机灵敏度、移动台最大可允许的发射功率、信干比的期望值、路径损耗与小区覆盖半径、小区容量的关系式,并以直线天线阵为例,计算了小区容量和小区的覆盖半径。  相似文献   
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97.
In this study,a high-density polyethylene(HDPE,5-mm-thick,0.95 g/cm3) surface was treated using an RF capacitive atmospheric pressure cold Ar plasma jet.By using this Ar plasma jet,a hydrophilic HDPE surface was formed during the plasma treatment.In particular, the effects of an additive gas(N2 or O2) on the HDPE surface treatment were investigated in detail.It was shown that the addition of N2 or O2 gas had an important influence on the HDPE surface treatment.Compared to pure Ar plasma treatment,a lower value of water contact angle (WCA) was obtained when a trace of N2 or O2 gas was added.It was also found that besides the quantities of active species in the plasma jet,the treatment temperature played an important role in the HDPE surface treatment.This is because surface molecular motion is not negligible when the treatment temperature is close to the melting point of the polymer.  相似文献   
98.
This paper describes a similarity measure for images which can be used in image-based topological localization and topological SLAM problems by autonomous robots with low computational resources. Instead of storing the images in the robot’s memory, we propose a compact signature to be extracted from the images. The signature is based on the calculation of the 2D Haar Wavelet Transform of the gray-level image and its size is only 170 bytes. We called this signature the DWT-signature. We exploit the frequency and space localization property of the wavelet transform to match the images grabbed by the perspective camera mounted on board the robot and the reference panoramic images built using an automatic image stitching procedure. The proposed signature allows, at the same time, memory saving and fast and efficient similarity calculation. For the topological SLAM problem we also present a simple implementation of a loop-closure detection based on the proposed signature.We report experiments showing the effectiveness of the proposed image similarity measure using two kinds of small robots: an AIBO ERS-7 robot of the RoboCup Araibo Team of the University of Tokyo and a Kondo KHR-1HV humanoid robot of the IAS-Lab of the University of Padua.  相似文献   
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100.
We previously found that proteinaceous protease inhibitors homologous to Streptomyces subtilisin inhibitor (SSI) are widely produced by various Streptomyces species, and we designated them "SSI-like proteins" (Taguchi S, Kikuchi H, Suzuki M, Kojima S, Terabe M, Miura K, Nakase T, Momose H [1993] Appl Environ Microbiol 59:4338-4341). In this study, SSI-like proteins from five strains of the genus Streptoverticillium were purified and sequenced, and molecular phylogenetic trees were constructed on the basis of the determined amino acid sequences together with those determined previously for Streptomyces species. The phylogenetic trees showed that SSI-like proteins from Streptoverticillium species are phylogenetically included in Streptomyces SSI-like proteins but form a monophyletic group as a distinct lineage within the Streptomyces proteins. This provides an alternative phylogenetic framework to the previous one based on partial small ribosomal RNA sequences, and it may indicate that the phylogenetic affiliation of the genus Streptoverticillium should be revised. The phylogenetic trees also suggested that SSI-like proteins possessing arginine or methionine at the P1 site, the major reactive center site toward target proteases, arose multiple times on independent lineages from ancestral proteins possessing lysine at the P1 site. Most of the codon changes at the P1 site inferred to have occurred during the evolution of SSI-like proteins are consistent with those inferred from the extremely high G + C content of Streptomyces genomes. The inferred minimum number of amino acid replacements at the P1 site was nearly equal to the average number for all the variable sites. It thus appears that positive Darwinian selection, which has been postulated to account for accelerated rates of amino acid replacement at the major reaction center site of mammalian protease inhibitors, may not have dictated the evolution of the bacterial SSI-like proteins.  相似文献   
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