Antibiotic activity of organic compounds and their average quasi-valence number

Summary It is shown that the average quasi-valence numbers of antibiotics inhibiting protein synthesis are well defined and lie in the region of average quasi-valence numbers of amino acids, while the average quasi-valence numbers of antibiotics inhibiting DNA or RNA synthesis have higher values. Possible explanations of these findings and their implications on the design and selection of antibiotics are discussed.     

Cytostatic activity of organic compounds and their average quasi-valence number

Summary It is found that the average quasi-valence numbers of alkylating cytostatics lie in the region of potential carcinogens, while the average quasi-valence numbers of antimetabolites predominantly cover the region of noncarcinogens. Implications of this finding on the design of new drugs are discussed.     

关于一类非线性波动方程的准确周期解

应用Jacobi椭圆函数展开法求得了两种非线性波动方程的准确周期解,而且这些周期解在一定条件下可以退化为包络孤立波解。     

Characteristics of the Middle-Late Triassic sedimentary facies assemblages in the Songpan-Ruoergai area

The Middle-Late Triassic sedimentary rocks in the Songpan-Ruoergai area mainly consist of calcareous siltstone, muddy limestone, lithic arkose, feldspathic litharenite, mudstone, wormkalk, oolithic limestone, and conglomerate. Except for limestone bed increasing eastward longitudinally and vertically, the calcareous component of the sandstones increases obviously. Abundant benthic and plant fossils and their clasts occur within these rocks. The sedimentary structures predominately contain flaser, parallel, tabular, wavy, and herringbone cross beddings. These data coevally imply that the Middle-Late Triassic sediments deposited in the fluvial, lake and tide environments. Additionally, the rocks display graded, parallel, hummocky beddings, and sandy lamination, a feature characteristic of storm deposits.     

论我国公民体育权利实现的法律保障

通过对我国公民体育权利保护立法现状的分析,找出当前我国公民体育权利实现中存在的法律问题,并对加强和完善我国公民体育权利实现的法律保障提出对策性研究。     

雌三醇单克隆抗体的制备与表征

活化雌三醇 (E3 )C3处的酚—OH ,与牛血清白蛋白 (BSA)偶联 ,制备得E3 的完全抗原。利用完全抗原免疫动物 ,采用单克隆抗体技术 ,经过细胞融合、克隆筛选、扩大培养、动物体内诱生等过程 ,最后获得了E3 的单克隆抗体。对纯化的单克隆抗体的性质进行表征 ,结果表明 :抗体的效价为 6 0× 10 -10 mol L ,抗体属于IgG1型 ,分子量为 16 80 0 0u ,单克隆抗体与固定化抗原亲和常数为4 7× 10 7L mol。     

黑河流域张掖段不同主体功能区水环境承载力评价

水环境承载能力是地区经济发展和生态环境保护的关键因素,为精准查明张掖市水环境承载力状况,基于各区县主体功能定位,从水资源、排放强度、水环境质量和水生态4个维度选取合理指标,构建了复合型水环境承载力评价指标体系,利用层次分析法和综合指数法评价了2018-2020年各区县水环境承载力,结果表明：2018年各区县评价指数介于63.9-79.4,民乐县和高台县为临界超载,其他县区不超载;2019年评价指数介于63.2-86.9,临泽县、民乐县和高台县为临界超载,其他县区不超载;2020年评价指数介于70.6-88.6,六县区均处于不超载状态,总体张掖市的水环境承载能力现状良好,且逐年提升。但临泽县、山丹县、民乐县和高台县刚脱离“临界超载”,“不超载”状态优势不存在,仍有较大提升空间。不同功能区4个指标对水环境承载力的影响程度排序情况有所差别,可依据评价结果提供的主要影响指标或压力指标信息,针对性采取改善提升不同功能区水环境承载力的措施。     

纤维毛壳菌玉米秸发酵饲料的系统毒理分析和营养价值测定

玉米秸经纤维毛壳菌（ Ｃｈａｅｔｏ ｍｉｃｕ ｍ ｃｅｌｌｕｌｏｌｙｔｉｃｕ ｍ ） Ｓ Ｍ２７ 发酵后制成的纤维蛋白饲料（ Ｆｅｒｍ ｅｔｅｄ ｐｒｏｄｕｃｔ ｏｆ ｃｏｒｎ ｓｔａｌｋ , Ｆ Ｐ Ｃ Ｓ） 作为日粮中的粗蛋白源,喂饲白鼠和白兔,进行了系统的毒理分析和营养价值测定．毒理测试包括急性毒性试验（ Ｌ Ｄ５０ 测定和７ ｄ 喂养试验） ,蓄积毒性试验、致突变试验、９０ ｄ 喂养毒性测定等,结果表明 Ｆ Ｐ Ｃ Ｓ 的 Ｌ Ｄ５０ 对瑞士小白鼠和 Ｗｉｓｔａｒ 大白鼠都大于２１５４ ｇ／ｋｇ 体重,在７ ｄ 、２８ ｄ 和９０ ｄ 喂养中都未曾观察到动物机体有异常表现．微核试验中,各试验组与阴性对照组间无显著差异（ ｐ ＞ ０ ．０５） ,与阳性对照组间则有显著差异． Ｆ Ｐ Ｃ Ｓ 在白兔日粮中由１７ ．５ ％ （ ｗ／ ｗ ,重量比,下同） 增至３２ ．５ ％ 时,其营养价值递减,但粗蛋白的消化率各组间无显著变化（ ｐ ＞ ０ ．０５） ,多指标多重分析表明, Ｆ Ｐ Ｃ Ｓ 作为动物饲料有安全性,具有粗蛋白可被消化而残余粗纤维难被消化的特点,适用于作为反刍动物日粮中粗蛋白的部分替代物．     

AdaBoost-PSO-LSTM网络实时预测机动轨迹

针对自主空战中轨迹预测难以同时保持高预测精度和短预测时间的问题, 提出一种自适应增强的粒子群优化长短期记忆网络预测方法。首先,建立三自由度无人机动力学模型, 解决机动轨迹的数据来源问题。其次,分析长短期记忆网络, 并引入在线预测的滑动模块输入矩阵, 利用粒子群优化算法代替传统基于时间的反向传播算法进行网络内部权值更新; 同时为解决优化算法非定向性问题, 提出数据共享方法。然后,为进一步提高预测精度, 采用自适应增强算法搭建外框架, 通过控制弱预测器的数量平衡预测精度与预测时间。最后, 在一段变化较为频繁的轨迹进行预测, 与5种神经网络预测方法进行比较, 结果表明所提方法能够较好地满足精度和时间要求。     

Dissection of the molecular mechanisms that control the nuclear accumulation of transport factors importin-α and CAS in stressed cells

The physiological state of eukaryotic cells controls nuclear trafficking of numerous cargos. For example, stress results in the inhibition of classical protein import, which is characterized by the redistribution of several transport factors. As such, importin-alpha and cellular apoptosis susceptibility protein (CAS) accumulate in nuclei of heat-shocked cells; however, the mechanisms underlying this relocation are not fully understood. We now show that heat upregulates the initial docking of importin-alpha at the nuclear envelope and stimulates the translocation of CAS into the nuclear interior. Moreover, heat exposure compromises the exit of importin-alpha from nuclei and drastically increases its retention in the nucleoplasm, whereas CAS nuclear exit and retention are less affected. Taken together, our results support the idea that heat shock regulates importin-alpha and CAS nuclear accumulation at several levels. The combination of different stress-induced changes leads to the nuclear concentration of both transport factors in heat-stressed cells.