Effects of noninvasive delayed limb ischemic preconditioning on prognosis of myocardial infarction

AIM: To study the effects of noninvasive delayed limb ischemia preconditioning (NDLIP) on animal cardiac function, myocardial morphology and myocardial apoptosis after myocardial infarction (MI). METHODS: Healthy SD male rats[n=45, weighing (250±10) g] were randomly divided into 3 groups:MI group:the animal model of MI was established by surgical ligation of left anterior descending artery (LAD) after 2 weeks; NDLIP group:after the success of the MI animal model, NDLIP was carried out every other day until the 4th, 6th and 8th weeks; sham group:as the negative control group, the animals were taken heart LAD threading but no ligation. All rats were fed conventionally. At the end of the 4th, 6th and 8th weeks, all rats were made ventricular intubation, and then the hemodynamic parameters were recorded. The blood samples were withdrawn from the abdominal aorta and the serum was separated via centrifugation. The serum contents of Bcl-2 and Bax were measured by ELISA. Left ventricular anterior wall was homogenized. The mitochondrial respiratory chain complexes Ⅰ, Ⅱ, Ⅲ and Ⅳ in the myocardial tissues were detected by ELISA. RESULTS: At the end of the 4th, 6th and 8th weeks, compared with MI group, left ventricular systolic pressure in NDLIP group was significantly increased, while left ventricular end-diastolic pressure in NDLIP group was significantly decreased (both P<0.05). Mitochondrial respiratory chain complexesⅠ, Ⅱ, Ⅲ and Ⅳ in NDLIP group were significantly increased (P<0.05). The serum level of Bcl-2 in NDLIP group was significantly increased and Bax level was reduced remarkably (both P<0.01). CONCLUSION: NDLIP improves the hemodynamic indexes, promotes the mitochondrial respiratory function and inhibits cell apoptosis, thus improving the prognosis of MI.     

基于霍尔效应的微小压强测量装置的设计与实现

针对化工液体的微小压强测量中所存在的测量复杂、精度低的问题，设计一种基于霍尔效应的测量流体微小压强变化的装置。该测量装置通过前端受力装置来承受液体压强的变化而产生一定的位移，并转换成霍尔电动势，经放大调理电路，最后接电压表显示相应的电压值。根据输出电压与液体压强之间的关系即可得到相应深度的压强大小。在实验中，电压表精确到1mV，最小可测量到0.792Pa的压强变化，其测量精度较高。该装置体积小、通用性强，具有较好的应用前景。     

福建省内陆捕捞渔具的作业类型及其数量组成分析

本文根据2009年8月至12月福建省捕捞业渔具渔法普查资料,分析整理了福建内陆地区捕捞业渔具渔法现状调查数据.结果表明:福建内陆地区捕捞渔具有刺网类、钓具类、笼壶类、拖网类、张网类、陷阱类、耙刺类、地拉网类、敷网类、掩罩类、抄网类和杂渔具等12个类别、21种作业型式、渔具总数量123204张(个、顶等).按渔具类别划分...     

冷却塔混凝土粗糙度对平均风压系数的影响

采用CFD方法研究全尺寸双曲冷却塔表面混凝土粗糙度对风压系数的影响.在规范规定的粗糙度范围内，分别对表面混凝土光滑以及表面混凝土有不同粗糙度高度的冷却塔全尺寸模型进行了数值模拟.将不同工况下的风压系数计算值与以往文献的风洞试验和现场实测数据进行了比较.研究结果表明：冷却塔全尺寸CFD模拟虽然解决了雷诺数相似问题，但纯粹的光滑壁面冷却塔在CFD计算中得到的平均风压系数比实际值偏离较大；在冷却塔全尺寸CFD模拟中必须考虑实际冷却塔表面的粗糙度对其平均风压系数的影响.     

Square‐mesh codend length and selectivity in southeastern Australian stow nets

Abstract The relationship between the amount of square mesh in codends and selectivity was investigated for an Australian penaeid stow‐net fishery. Three lengths (3, 2 and 1 m) of square‐mesh codend made from 27‐mm mesh hung on the bar were alternately tested with a conventional 34‐mm diamond‐mesh design during two covered‐codend experiments. Compared with the conventional codend, the square‐mesh configurations incrementally selected school prawns, Metapenaeus macleayi (Haswell) across narrower selection ranges (SR) and mostly at greater sizes at 50% retention (L₅₀), while retaining fewer fish. Irrespective of the mesh configuration or square‐mesh codend length, there were significant differences between experiments (attributed to water flow) and impacts of catch weight on the selectivity of school prawns. Both variables had a negative relationship with L₅₀, while water flow similarly affected SR. This study reaffirms the utility of square‐mesh codends as a key input control for managing the selectivity of penaeid‐catching gears.     

我国玻璃钢渔船发展历程及建造工艺技术

介绍了我国大陆及台湾玻璃钢渔船的发展历程及台湾玻璃钢渔船迅速发展所采取的措施,概要介绍我国玻璃钢渔船相关技术法规建设及真空树脂导入成型工艺技术的应用情况及存在的问题,探讨了今后的研究方向。     

放牧压力对草原砂质栗钙土微生物量C,N,P影响的研究

对不同放牧压力下草原砂质栗钙土微生物量C、N、P进行较为系统地研究。结果表明：就土壤原土来看,随着放牧压力的增大,土壤微生物量C,N先增加后减少;土壤微生物量C在放牧率2.67只羊/hm2时相对较高,微生物量P随着放牧压力的增大逐渐降低。     

基于《物权法》的中国捕捞权保护制度的探索

《物权法》明确了捕捞权和养殖权的用益物权属性,并规定其受法律保护。但依据我国现有渔业法律制度,实施《物权法》有关保护捕捞权的法律规定还存在一定困难。通过比较分析《物权法》和《渔业法》及相关法规对捕捞权的规定,考察造成捕捞权损害的主要原因,提出了我国捕捞权保护制度的路径选择:(1) 将近岸海洋渔场和内陆水域渔场按县级或县级以下基层行政区域进行划分,确定给所属区域内的传统捕捞渔民专属使用,从而明确捕捞权主体和客体,为建立捕捞权保护制度提供基础。(2) 建立捕捞权损害评估体系,制定捕捞权损害赔偿、补偿标准,规范捕捞权损害赔偿、补偿程序,健全和完善捕捞权损害赔偿、补偿制度。     

绕基础转动模式下刚性挡土墙主动土压力的计算

采用考虑墙体位移模式和转角的土压力计算方法,能较好地反映挡土墙实际工作条件下的位移情况,并且能计算挡土墙任意转角下的主动土压力,避免了采用库仑主动土压力理论计算得到土压力偏小而使设计安全度降低的缺点。因此,本文提出的土压力计算方法对挡土墙的设计及验算有一定的参考价值。     

缸内直喷汽油机旋流喷射喷雾特性影响因素的分析研究

为了研究影响缸内直喷汽油机高压旋流喷嘴喷雾特性的因素,对高压旋流喷射初始阶段运动进行了理论分析研究,确定了影响初始喷雾旋流体运动的无量纲参数。通过试验改变空心旋流体内外压差、初始旋流强度、旋流体油膜厚度,发现喷雾特性呈不同的变化趋势。随着旋流体内外压力差的增大,喷雾锥角明显减小而贯穿度变化不大;旋流强度增加,喷雾贯穿距离明显增加,而喷雾锥角变化不大;增加旋流体初始厚度,可以使喷雾在自由空间中外形尺寸增加。