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51.
Expression of the mei3 gene is sufficient to induce meiosis in the fission yeast Schizosaccharomyces pombe. The mei3 gene is located 0.64 Mb from the telomere of the left arm of Sz. pombe chromosome II. We have sequenced and analysed 107 kb of DNA from the mei3 genomic region. The sequence includes 14 known genes (bag1-B, csh3, dps1, gpt1, mei3, mfm3, pac1, prp31, rpl38-1, rpn3, rti1, spa1, spm1 and ubc4) and 26 other open reading frames (ORFs) longer than 100 codons: a density of one protein-coding gene per 2.7 kb. Twenty-one of the 40 ORFs (53%) have introns. In addition there is one lone Tf1 transposon long terminal repeat (LTR), tRNA(Trp) and tRNA(Ser) genes and a 5S rRNA gene. 14 of the novel ORFs show sequence similarities which suggest functions of their products, including a coatomer alpha-subunit, a catechol O-methyltransferase, protein kinase, asparagine synthetase, zinc metalloprotease, acetyltransferase, phosphatidylinositol 4-kinase, inositol polyphosphate phosphatase, GTPase-activating protein, permease, pre-mRNA splicing factor, 20S proteasome component and a thioredoxin-like protein. One predicted protein has similarity to the human Cockayne syndrome protein CSA and one with human GTPase XPA binding protein XAB1. Three ORFs are likely to code for proteins because they have sequence similarity with hypothetical proteins, three encode predicted coiled-coil proteins and four are sequence orphans.  相似文献   
52.
系统介绍了WD 61 5柴油发动机凸轮轴与挺柱点磨损的表象 ,采用兰德式问题分析技术 ,对其原因进行了全面分析 ,找出了真正的原因。  相似文献   
53.
本文对WD615发动机各负荷工况的热平衡进行了分析,主要确定了该发动机冷却水和废气带走的热量比例,为大客车的冬季取暖做好准备。  相似文献   
54.
提出了一种可适用于电动四驱混和动力车的功率分配策略。定义了综合考虑发动机效率、ISG电机效率、后轴驱动电机效率的系统总效率的表达式,用来作为功率分配的依据;提出了包括功率需求计算、电池SOC管理、功率分配表在内的功率分配模型,用来实现基于系统总效率最大的多动力源的功率分配;建立了Simulink经济性仿真平台,通过对该功率分配策略的仿真计算表明,通过该分配策略可以明显改善车辆的经济性,因而具有较好的应用前景。  相似文献   
55.
The effect of water soluble polyphenolic extract of peanut skin (PE) was investigated for its hypolipidemic properties in rats on Western diet. Seven-weeks old Wistar rats received control diet (AIN-93G), Western diet with and without a bolus of PE five times a week for 10weeks. Group which received 300mg/kg body weight showed significantly reduced body weight and epididymal fat. Plasma and liver triglyceride (TG) and cholesterol (TC) levels were significantly reduced while faecal secretion of TG and TC was greatly increased upon PE administration. Liver mRNA expression of enzymes involved in fatty acid synthesis, such as fatty acid synthase (FAS), sterol receptor element binding protein (SREBP)-1c, acetyl-CoA carboxylase (ACC1) and lipid uptake genes, such as PPARγ, were decreased, while PPARα was up-regulated by administration of PE. These data suggest that administration of PE may contribute to the improved lipid homoeostasis in rats on diets high in cholesterol and lipids.  相似文献   
56.
Shape uniformity of fruits and vegetables is important whether they are to be fresh marketed or processed. To achieve the desired uniformity, fruits must be inspected and classified. Although manual sorting of agricultural products is potentially accurate, in practice it reveals subjective and inconsistent. Computer vision has become a proven, reliable tool for describing product shape. Depending on the product, misshapenness or malformation expresses as poor axial symmetry, excessive curvature of the fruit longitudinal axis, several types of protruding zones and abnormal concavities, lack of cross section circularity, etc. Here we review some two-dimensional computer vision methods applied throughout the past 25 years for determining the shape of horticultural produce. While a number of the works cited achieved high classification accuracy in two categories (well-formed, misshapen), only a few of the systems referred were able to classify in more than two classes, or have been tested online.  相似文献   
57.
In recent years, oil resources are becoming exhausted making their exorbitant prices. In addition to the depletion rate of pollution reaches alarming levels. Because of these facts and in order to diminish the fatality of those problems, the automotive technology provided by Cem electric energy that is treated as a non-polluting energy is considered as a solution. In this paper, we propose a configuration of a 4WD vehicle (Four Wheel Drive) with two asynchronous motors can be ordered by the technique of Direct Torque Control. The vehicle can operate in single front wheel (wheel), which means that the engine torque requested develops only in the case of the 4WD torque is developed by two motor (I and II). An implementation of the algorithm is performed in our laboratory on two identical motors with a variable set point torque which directly reflects the variation of the speed imposed by the driver.  相似文献   
58.
Autophagy is a critical cytoprotective mechanism against stress, which is initiated by the protein kinase Unc-51-like kinase 1 (ULK1) complex. Autophagy plays a role in both inhibiting the progression of diseases and facilitating pathogenesis, so it is critical to elucidate the mechanisms regulating individual components of the autophagy machinery under various conditions. Here, we examined whether ULK1 complex component autophagy-related protein 101 (ATG101) is downregulated via ubiquitination, and whether this in turn suppresses autophagy activity in cancer cells. Knockout of ATG101 in cancer cells using CRISPR resulted in severe growth retardation and lower survival under nutrient starvation. Transfection of mutant ATG101 revealed that the C-terminal region is a key domain of ubiquitination, while co-immunoprecipitation and knockdown experiments revealed that HECT, UBA and WWE domain containing E3 ubiquitin protein ligase 1(HUWE1) is a major E3 ubiquitin ligase targeting ATG101. Protein levels of ATG101 was more stable and the related-autophagy activity was higher in HUWE1-depleted cancer cells compared to wild type (WT) controls, indicating that HUWE1-mediated ubiquitination promotes ATG101 degradation. Moreover, enhanced autophagy in HUWE1-depleted cancer cells was reversed by siRNA-mediated ATG101 knockdown. Stable ATG101 level in HUWE1-depleted cells was a strong driver of autophagosome formation similar to upregulation of the known HUWE1 substrate WD repeat domain, phosphoinositide interacting 2 (WIPI2). Cellular survival rates were higher in HUWE1-knockdown cancer cells compared to controls, while concomitant siRNA-mediated ATG101 knockdown tends to increase apoptosis rate. Collectively, these results suggest that HUWE1 normally serves to suppress autophagy by ubiquitinating and triggering degradation of ATG101 and WIPI2, which in turn represses the survival of cancer cells. Accordingly, ATG101-mediated autophagy may play a critical role in overcoming metabolic stress, thereby contributing to the growth, survival, and treatment resistance of certain cancers.  相似文献   
59.
为了充分认识目的优势菌种经油藏运移后在产出水中分布的规律与数量,准确分析和客观评价MEOR现场试验效果,利用绿色荧光蛋白(GFP)基因标记目的菌,通过绿色荧光蛋白跟踪监测目的菌的动态信息。构建含有GFP基因的质粒pET-30a(+)-EGFP,并将其成功导入JD中。对构建的JD(gfp)工程菌进行培养发现,该工程菌在含有Kan质量浓度50μg/mL的培养条件下,重组质粒在JD(gfp)工程菌体内传代稳定,绿色荧光的表达稳定。但是在没有选择压力的培养条件下,重组质粒在JD工程菌胞体内有丢失现象。与野生菌混合培养,JD(gfp)工程菌具有很好的配伍性和竞争性,并且不发生重组质粒的水平转移,因此在环境中释放是安全的。  相似文献   
60.
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