ZF从设计概念到系列产品的系统供应者

ZF集团在传动系统、转向器和底盘技术方面处于独特的地位,根据这方面特点,我们把各个子公司,组成一个完整的系统,本文将介绍ZF帕骚（Passau）在非公路传动系统和轴系方面处于领先地位的情况。     

齿轮的现代计算方法

在汽车工业领域,高耐用度和低噪音是现代齿轮设计的两个最重要的研究课题,由于这个原因,据于基本的设计技能和专门的经验编制新的有效的计算方法已越来越重要的。根据齿轮制造师的观战提供和说明的现代和未来的发展,疲劳寿命计算已常作为齿轮设计过程的一种部分。许用应力、工作循环次数和试验的负载规律可以估算并予先确定,相应软件提供用户对于数据输入以及图表输出新特点的相互关系的对话,板理论程序对接触应力的优化实现十分合理的解技术,有际元（ＦＥＡ）分析对设计过程提供有效帮助,不仅齿轮本身,而且对其周转的部件和对齿轮系的有关影响都考虑在内。     

Altering the binuclear manganese cluster of arginase diminishes thermostability and catalytic function

Arginase is a thermostable (Tm = 75 degrees C) binuclear manganese metalloenzyme which hydrolyzes l-arginine to form l-ornithine and urea. The three-dimensional structures of native metal-depleted arginase, metal-loaded H101N arginase, and metal-depleted H101N arginase have been determined by X-ray crystallographic methods to probe the roles of the manganese ion in site A (Mn2+A) and its ligand H101 in catalysis and thermostability. We correlate these structures with thermal stability and catalytic activity measurements reported here and elsewhere [Cavalli, R. C., Burke, C. J., Kawamoto, S., Soprano, D. R., and Ash, D. E. (1994) Biochemistry 33, 10652-10657]. We conclude that the substitution of a wild-type histidine ligand to Mn2+A compromises metal binding, which in turn compromises protein thermostability and catalytic function. Therefore, a fully occupied binuclear manganese metal cluster is required for optimal catalysis and thermostability.     

Chromosome 16 in primary prostate cancer: a microsatellite analysis

OBJECTIVES: To evaluate whether orthotopic urinary diversion is a viable option for patients undergoing cystoprostatectomy for radio-recurrent prostate cancer (RRPC). METHODS: Between 1990 and 1996, we performed 34 salvage surgeries for RRPC, including 26 radical retropubic prostatectomies and 8 cystoprostatectomies. We determined the operative and postoperative complication rates and pathologic stage for the 8 patients undergoing cystoprostatectomy. RESULTS: Of the 8 patients in whom cystoprostatectomy was performed, 5 underwent ileal conduit diversion and 3 underwent orthotopic neobladder reconstruction. There were no intraoperative complications or perioperative mortalities. In the group with orthotopic neobladder, postoperative complications included pyelonephritis in 1 patient and prolonged ileus in another. In the group with ileal conduit, no short-term complications occurred; 1 patient developed an incisional hernia on long-term follow-up. All patients with neobladder reconstruction are continent during the day. One patient wears one pad at night. The other 2 are continent at night. CONCLUSIONS: Orthotopic urinary diversion is a valid option for selected patients with RRPC who require a cystoprostatectomy. This procedure can be performed with minimal complications, resulting in good continence and good quality of life.     

Post traumatic lumbar hernia

A lumbar hernia which had developed following blunt abdominopelvic trauma is described here. The successful surgical correction is reported.     

A genetic animal model of human neocortical heterotopia associated with seizures

Malformations of the human neocortex are commonly associated with developmental delays, mental retardation, and epilepsy. This study describes a novel neurologically mutant rat exhibiting a forebrain anomaly resembling the human neuronal migration disorder of double cortex. This mutant displays a telencephalic internal structural heterotopia (tish) that is inherited in an autosomal recessive manner. The bilateral heterotopia is prominent below the frontal and parietal neocortices but is rarely observed in temporal neocortex. Neurons in the heterotopia exhibit neocortical-like morphologies and send typical projections to subcortical sites; however, characteristic lamination and radial orientation are disturbed in the heterotopia. The period of neurogenesis during which cells in the heterotopia are generated is the same as in the normotopic neocortex; however, the cells in the heterotopia exhibit a "rim-to-core" neurogenetic pattern rather than the characteristic "inside-out" pattern observed in normotopic neocortex. Similar to the human syndrome of double cortex, some of the animals with the tish phenotype exhibit spontaneous recurrent electrographic and behavioral seizures. The tish rat is a unique neurological mutant that shares several features with a human cortical malformation associated with epilepsy. On the basis of its regional connectivity, histological composition, and period of neurogenesis, the heterotopic region in the tish rat is neocortical in nature. This neurological mutant represents a novel model system for investigating mechanisms of aberrant neocortical development and is likely to provide insights into the cellular and molecular events contributing to seizure development in dysplastic neocortex.     

Unfired refractories bonded with coal tar pitch

Conclusions Medium-temperature coal tar pitches are effective bonds for making unfired dolomite and dolomite —magnesite refractories by pressing bodies heated to 100–120°C. The features of the refractories with a pitch bond are the higher contents of carbon resistant to oxidation (about 4%), and the higher compressive strength (400–500 kg/cm²), and finally the higher hydration resistance (10 days).Refractories bonded with pitch are much better than products containing tar, and accordingly offer a greater resistance when used in oxygen converter linings.Translated from Ogneupory, No. 3, pp. 6–15, March, 1971.     

未来变速箱面临的挑战

现代传动系统必需满足足的燃油经济性，较少的有害气体排放和日益增大的舒适性要求，本文提出了可有助于达到这些目的方法，它可实现最佳的高效的自动变速箱和最佳的传动系操纵。