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关键词： 摩擦离合器   有限元   模态分析  

摘要： 在有限元技术基础上,采用ANSYS Workbench软件对摩擦离合器外壳体和内壳体进行模态分析,得到了摩擦离合器外壳体和内壳体的各阶固有频率和固有振型。分析结果为离合器结构设计及动态响应分析奠定了一定的理论基础。

关键词： 气胎离合器   结构   工作原理   装配   使用与维护  

摘要： 介绍了气胎离合器的结构、原理、装配、选型及其使用和维护。

关键词： Clutches (Machinery) -- Evaluation   Automobile brakes -- Evaluation  

摘要： The article offers information on two automobile products including medium-duty clutches and reduced stopping distance (RSD) brake drums from tucks parts manufacturer Alliance Truck Parts.

关键词： Brood reduction   Laying date   Laying order effect   Yellow-legged Gull   Yolk carotenoids   BARN SWALLOW EGGS   CAROTENOID CONCENTRATION   BETA-CAROTENE   ANTIOXIDANTS   IMMUNITY   SEX   DETERMINANTS   ALLOCATION   SIGNALS   QUALITY  

摘要： In gull species, the level of carotenoids in egg yolks is known to decrease along the egg laying sequence. However, the extent of this laying order effect is expected to vary among clutches according to laying date, due to possible differences between early-nesting and late-nesting females with regards to their ability to control the transfer of maternal resources to the eggs. A laying date effect could also result from a seasonal decline in the availability of dietary carotenoids. In this study, we collected data from Yellow-legged Gulls (Larus michahellis) breeding in southern Tunisia to investigate how nesting date interacts with egg-laying order in shaping patterns of within-clutch variation in yolk lutein, the most abundant carotenoid in this species. In particular, we examined (1) whether yolk lutein concentration declined along the laying sequence and (2) whether the extent of the decline differed among clutches according to laying date. Our results show that yolk lutein decreased along the laying sequence at the clutch level. More interestingly, they also show that the decrease in yolk lutein levels along the laying sequence was more pronounced in late clutches than in early clutches, although lutein levels in adult plasma did not vary according to laying date. Overall, these results support the hypothesis that the Yellow-legged Gull employs the brood reduction strategy and that said strategy is more drastically applied in late clutches than in early clutches. The relevance of female age and seasonal variation in chick-rearing conditions for these findings is discussed.

关键词： CLUTCHES (Machinery)   AUTOMOTIVE fuel consumption  

摘要： The article reports on a clutch piston technology developed by supplier Federal-Mogul Corp. that will improve fuel economy of vehicles while reducing emissions.

关键词： Adiponectin   Microalbuminuria   Vascular endothelial growth factor   Nitric oxide   Diabetic nephropathy   URINARY ALBUMIN EXCRETION   NF-KAPPA-B   NITRIC-OXIDE   ENDOTHELIAL DYSFUNCTION   MICROALBUMINURIA   NEPHROPATHY  

摘要： To determine whether adiponectin could reduce microalbuminuria and provide renal protective effects by improving endothelial dysfunction and uncoupling of the glomerular vascular endothelial growth factor (VEGF)-nitric oxide (NO) axis in streptozotocin-induced type 2 diabetic rats. Wistar rats were randomly divided into normal control group, diabetic nephropathy (DN) group induced by high-fat feeding and streptozotocin, diabetic rats injected with adenovirus-expressed adiponectin (AD-AdipoQ), and diabetic rats injected with AD-IRES-EGFP as control. Blood and urine samples were collected. Endothelium-dependent vasodilatation (EDV) of the aorta was measured. Renal tissues were collected for CD34 immunohistochemistry. Glomerular NO and VEGF levels were measured by the Griess reaction and Western blot testing, respectively. Injections of AD-AdipoQ significantly increased serum adiponectin levels and reduced the urinary albumin-to-creatinine ratio in diabetic rats (P < 0.05). The levels of plasma glucose, serum insulin, high-sensitivity C-reactive protein, and malondialdehyde were significantly reduced in diabetic rats after injections of AD-AdipoQ (P < 0.05). Severe EDV impairment was observed in the DN group, which was improved by AD-AdipoQ. CD34 expression in the glomeruli was also higher in diabetic rats, indicating increased proliferation of glomerular endothelial cells. However, AD-AdipoQ improved the increased proliferation of endothelial cells in the glomeruli. Diabetic rats showed increased glomerular VEGF levels and reduced NO levels. This uncoupling of the VEGF-NO axis was partially improved by AD-AdipoQ. Adiponectin reduces the degree of microalbuminuria and has renal protective effects by improving endothelial dysfunction and uncoupling of the glomerular VEGF-NO axis in early diabetic nephropathy.

关键词： ANTIGEN RETRIEVAL   GLIOBLASTOMA-MULTIFORME   TISSUE   INFECTION   IMMUNOHISTOCHEMISTRY   ASSOCIATION   EXPRESSION   SEROPREVALENCE   NEUROBLASTOMA   PROMOTES  

摘要： Human cytomegalovirus (HCMV) has been indicated being a significant oncomodulator. Recent reports have suggested that an antiviral treatment alters the outcome of a glioblastoma. We analysed the performance of commercial HCMV-antibodies applying the immunohistochemical (IHC) methods on brain sample obtained from a subject with a verified HCMV infection, on samples obtained from 14 control subjects, and on a tissue microarray block containing cores of various brain tumours. Based on these trials, we selected the best performing antibody and analysed a cohort of 417 extra- and intra-axial brain tumours such as gliomas, medulloblastomas, primary diffuse large B-cell lymphomas, and meningiomas. HCMV protein pp65 immunoreactivity was observed in all types of tumours analysed, and the IHC expression did not depend on the patient's age, gender, tumour type, or grade. The labelling pattern observed in the tumours differed from the labelling pattern observed in the tissue with an active HCMV infection. The HCMV protein was expressed in up to 90% of all the tumours investigated. Our results are in accordance with previous reports regarding the HCMV protein expression in glioblastomas and medulloblastomas. In addition, the HCMV protein expression was seen in primary brain lymphomas, lowgrade gliomas, and in meningiomas. Our results indicate that the HCMV protein pp65 expression is common in intra- and extra-axial brain tumours. Thus, the assessment of the HCMV expression in tumours of various origins and pathologically altered tissue in conditions such as inflammation, infection, and even degeneration should certainly be facilitated.

关键词： 液压控制   双离合器   动力传动系统   振动  

摘要： 针对双离合器动力传动系统振动问题,建立双离合器动力传动系统动力学和液压控制系统模型,对动力传动系统中发动机和离合器瞬态变化进行控制,研究了发动机、离合器振动及液压控制系统稳定性。研究结果表明,发动机在传递动力时,会产生振动和瞬时速度冲击,经过双离合器输出力矩比较稳定,在惯性阶段离合器的速度比最后转矩振荡阶段波动明显,液压控制系统控制精度较高,动力传动系统振动比较小。