稻纵卷叶螟产卵模型

本文报道了稻纵卷叶螟成虫的性比、寿命.产卵.潜在生殖力以及不同温度对其产卵的影响;不同的世代成虫性比不同,其变化范围为1:0.8—1.3;成虫的寿命平均为4.7天;雌成虫一般产卵2—3次,总产卵量为101.38±38.153粒/雌;但其潜在生殖力达223 8粒/雌。根据实验结果,组建了以温度为自变量的产卵模型.     

全球化下的跨国高等教育：内涵与动因

全球化作为一种必然的趋势对教育产生了深远的影响,近几十年来蓬勃发展的跨国高等教育就是其中之一.跨国高等教育首先是指高等教育领域中的跨国教育现象,它也是在全球化进程中高等教育国际化的一个渐进发展的过程,表现为多种活动形式.从全球化发展的进程和高等教育发展的历史来看,跨国高等教育是由多种因素合力推动的结果.     

Hypertonic saline resuscitation reduces apoptosis of intestinal mucosa in a rat model of hemorrhagic shock

Objective: To investigate the early effects of hypertonic and isotonic saline solutions on apoptosis of intestinal mueosa in rats with hemorrhagic shock. Methods: A model of rat with severe hemorrhagic shock was established in 21 Spragne-Dawley (SD) rats. The rats were randomly divided into the sham group, normal saline resuscitation (NS) group, and hypertonic saline resuscitation (HTS) group, with 7 in each group. We detected and compared the apoptosis in small intestinal mucosa of rats after hemorrhagic shock and resuscitation by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL), FITC (fluo-rescein-iso-tbiocyanate)-Annexin V/PI (propidium iodide) double staining method, and flow cytometry. Results: In the early stage of hemorrhagic shock and resuscitation, marked apoptosis of small intestinal mucosa in the rats of both NS and HTS groups was observed. The numbers of apoptotic cells in these two groups were significantly greater than that in the sham group (P＜0.01). In the HTS group, the apoptic cells significantly decreased, compared with the NS group (P＜0.01). Conclusion: In this rat model of severe hemorrhagic shock, the HTS resuscitation of small volume is more effective than the NS resuscitation in reducing apoptosis of intestinal mucosa in rats, which may improve the prognosis of trauma.     

钛酸铅的制备及光催化活性

用混合氧化物法制备钙钛矿型复合氧化物ＰｂＴｉＯ３，提出较合适的制备条件。制得的ＰｂＴｉＯ３纯度高，颗粒均匀，细度较好．在ＰｂＴｉＯ３悬浮水溶液中染料的光催化脱色率超过９０％。     

A model based algorithm for fast DPIV computing

Traditional DPIV (Digital Particle Image Velocimetry) methods are mostly based on area-correlation (Willert, C. E., 1991). Though proven to be very time-consuming and very much error prone, they are widely adopted because of they are conceptually simple and easily implemented, and also because there are few alternatives. This paper proposes a non-correlation, conceptually new, fast and efficient approach for DPIV, which takes the nature of flow into consideration. An Incompressible Affined Flow Model (IAFM) is introduced to describe a flow that incorporates rational restraints into the computation. This IAFM, combined with a modified optical flow method-named Total Optical Flow Computation (TOFC), provides a linear system solution to DPIV. Experimental results on real images showed our method to be a very promising approach for DPIV.     

Media multitasking,attention, and comprehension: a deep investigation into fragmented reading

Educational technology research and development - As students are processing information from digital media and educational materials, they are increasingly being interrupted by competing media and...     

以专业选修课为载体培养研究生创新能力的实践

叙述了在研究生选修课“特种成型技术”的教学实践中,作者结合科学学、创造学及其心理学,建立了一种新的教学模式:即在讲授各种特种成型技术的同时,注重这些技术的形成及发展过程,而且,更注重技术发明者思考问题的方法及成功的途径,以有助于研究生对创新的理解和创新能力的提高。     

鸡羽管螨病

鸡羽管螨寄生在鸡的羽管中,当严重感染时,鸡的大量羽管断脱,似“剪毛”,严重影响鸡的生长发育和产蛋量.本文简略地阐述了鸡羽管螨的形态、流行特点、感染途径、临床症状、诊断和治疗.     

稻飞虱及其节肢类捕食者的生态位关系研究

对稻飞虱及其节肢类捕食性天敌的空间、时间以及时间—空间生态位关系进行分析,从理论上说明了捕食性天敌对稻飞虱的控制作用。早稻群落中,食虫沟瘤蛛和水狼蛛是稻飞虱的主要捕食者,而且它们之间存在明显的竞争作用。晚稻群落中食虫沟瘤蛛对稻飞虱的捕食作用仍然占主导地位,但由于缺乏食物资源,各捕食性种类之间的竞争作用加剧。     

Purification and some properties of a β-glucanase from a strain,Trichoderma reesei GXC

β-glucanase was purified from a solid-state culture ofTrichoderma reesei on wheat bran in three steps which comprised ammonium sulfate precipitation, Sephadex G-100 chromatography, and DEAE-Sephadex A-50 chromatography. The molecular mass was determined to be 35.21 kilodaltons by sodium dodecyl sulfate-12.5% polyacrylamide gel electrophoresis. The β-glucanase at low pHs was more stable than that at high pHs, and optimum pH was 5.0. The optimum temperature was 60°C, and β-glucanase was relatively stable at below 40°C for 60 min. TheK _m of the enzyme on β-glucan was 10.86 mg/ml, and theV _max on β-glucan was 14286 μmol of glucose equivalents per mg of the pure enzyme per min. The β-glucanase activity was significantly inhibited by Fe³⁺ ions, and was reduced in the presence of Cu²⁺ ions, Mn²⁺ ions and Mg²⁺ ions at 5 mmol/L and 10 mmol/L, respectively. The β-glucanase activity was stimulated by Co²⁺ ions, Ca²⁺ ions, Zn²⁺ ions, and Fe²⁺ ions at 1 mmol/L and 5 mmol/L, respectively. Project supported by Foundation for University Key Teacher of the State Ministry of Education, the National Natural Science Foundation of China (No. 30000118) and Zhejiang Provincial Natural Science Foundation of China (No. 399409).