基于个体生态模型在渔业科学中的应用研究现状

基于个体生态模型(IBM)于20世纪70年代提出,数十年间在渔业科学领域得到广泛应用,现已成为渔业科学研究的重要手段之一。本文主要介绍了IBM的基本概念和研究方法,概述了国内外研究现状以及在渔业科学中的应用,分析了模型在应用中存在的问题、未来发展方向及趋势。研究认为,IBM在渔业科学研究和应用过程中需充分考虑以下问题:(1)了解模拟对象的生活史过程生物学特性,以及其栖息地环境特征;(2)针对不同的对象选用合适的环境因子和参数;(3)参考经典的生态学理论框架和方法来建立和分析个体模型;(4)综合统计分析、海洋遥感、地理信息系统等方法;(5)利用野外和敏感性试验获得实测数据,以校正IBM模型并提高精度。     

The influence of stress sensitivity on productionof hydraulically-fractured tight gas wells

This paper takes Sulige Gas Field as a case study and used three methods including laboratory experiments,production performance analysis and reservoir simulation to study the influence of stress sensitivity on production of fractured tight gas wells.The results show that the fracture length and conductivity of hydraulically created fracture are reduced more than 50%,and the stress sensitivity of hydraulically created fracture is stronger than that of matrix.With the increase of gas production,the influence of stress sensitivity becomes stronger,and finally results in 18% reduction of gas production,and hydraulically created fractures play an important role in the influence of stress sensitivity.     

Structure design and fabrication for resonant accelerometer based on electrostatic stiffness

The introduced resonant accelerometer makes use of the equivalent electrostatic stiffness to sense the acceleration. The sensitivity can be adjusted by changing the applied sensing voltage and it is robust for the fabrication error. According to the sensing principle,the dynamic model of the single beam accelerometer is built along with the no-linear relationship of the output frequency and the displacement of all positive components. When the stiffness of the vibrating beam is much bigger than the stiffness of the fold beam, the sensitivity can effective achieve. It is the restriction for the structure design. For the differential structure, mode analysis shows it is a lower mode in plane for the work mode. Decreasing the stiffness of connected end for the double vibrating beam can reduce the disturbance error. The bulk micromachining for the resonant accelerometer can achieve high depth width ration etching. The experiment find the structure is not broken and there is the same frequency disturbance problem. FM is suggested to deal with the disturbance. Theory analysis and test provides some important conclusions for the design of the novel type resonant accelerometer.     

QTL analysis of photoperiod sensitivity in common buckwheat by using markers for expressed sequence tags and photoperiod-sensitivity candidate genes

Photoperiod sensitivity is an important trait related to crop adaptation and ecological breeding in common buckwheat (Fagopyrum esculentum Moench). Although photoperiod sensitivity in this species is thought to be controlled by quantitative trait loci (QTLs), no genes or regions related to photoperiod sensitivity had been identified until now. Here, we identified QTLs controlling photoperiod sensitivity by QTL analysis in a segregating F₄ population (n = 100) derived from a cross of two autogamous lines, 02AL113(Kyukei SC2)LH.self and C0408-0 RP. The F₄ progenies were genotyped with three markers for photoperiod-sensitivity candidate genes, which were identified based on homology to photoperiod-sensitivity genes in Arabidopsis and 76 expressed sequence tag markers. Among the three photoperiod-sensitivity candidate genes (FeCCA1, FeELF3 and FeCOL3) identified in common buckwheat, FeELF3 was associated with photoperiod sensitivity. Two EST regions, Fest_L0606_4 and Fest_L0337_6, were associated with photoperiod sensitivity and explained 20.0% and 14.2% of the phenotypic variation, respectively. For both EST regions, the allele from 02AL113(Kyukei SC2)LH.self led to early flowering. An epistatic interaction was also confirmed between Fest_L0606_4 and Fest_L0337_6. These results demonstrate that photoperiod sensitivity in common buckwheat is controlled by a pathway consisting of photoperiod-sensitivity candidate genes as well as multiple gene action.     

酰基壳聚糖衍生物的合成·表征及pH敏感研究

[目的]以pH敏感的酰胺键为连接臂,制备两亲性壳聚糖衍生物。[方法]通过在壳聚糖2-NH2上引入疏水辛基和pH敏感的酰基,合成具有pH敏感性的两亲性壳聚糖接枝共聚物,并采用FTIR、1H-NMR和13C-NMR对其结构进行表征,使用紫外-可见分光光度计评价其pH敏感性。[结果]合成的4种两亲性酰基壳聚糖衍生物中,N-辛基-N＇-（3-羧基丙酰基）-壳聚糖（OCPC）和N-辛基-N＇-（3-羧基烯丙酰基）-壳聚糖（OCAC）在pH 4.5～7.4范围不具有pH敏感性;N-辛基-N＇-（邻羧基苯甲酰基）-壳聚糖聚合物（OCBC）和N-辛基-N＇-（2-羧基环己甲酰基）-壳聚糖（OCCC）在pH 5.0～6.0范围具有pH敏感性。[结论]合成的目的物OCCC有望作为新型pH敏感聚合物胶束材料增溶难溶性药物。     

安徽省玉米小斑病菌生理小种鉴定及对烯唑醇的敏感性

玉米小斑病是由玉蜀黍双极蠕孢(Bipolarismaydis)引起玉米叶部发病的病害之一,该病害广泛分布在世界玉米产区,严重影响玉米生产。玉米小斑病菌存在明显生理分化现象,目前已证实在中国存在T、C、S和O共4个小种。由于近年来不育细胞质的感病玉米自交系在玉米育     

2009年我国部分麦区小麦白粉菌群体对三唑酮和嘧菌酯的敏感性测定

自1976年以来,三唑酮一直就是我国防治小麦白粉病的主要药剂.1991年首次在山东省发现抗性菌株,之后其他地区也相继有抗药性菌株的报道.本实验室从1995年就开始监测小麦白粉菌对三唑酮的抗药性,研究结果表明,平均抗性水平和抗性菌株的频率均总体呈上升趋势[1-3].     

奶水牛子宫内膜炎细菌的分离鉴定及药敏试验分析

本试验通过对南宁市周边奶水牛场的105头子宫内膜炎患牛进行调查、采样,并用常规方法对细菌进行分离、鉴定及药敏分析。共分离到细菌200株,其中分离率较高的是肠杆菌科细菌(87株/43.5%)、弧菌科细菌(46株/23%)、非发酵细菌(35株/17.5%),另外还分离到葡萄球菌、链球菌和真菌32株,占分离菌株的16%,并且多数呈混合感染。药敏试验分析结果显示,大多数致病菌对恩诺沙星、庆大霉素具有较高敏感性,而对青霉素和氨苄青霉素产生了强耐药性,对氨基糖苷类药物链霉素和卡那霉素也产生了不同程度的耐药性。     

常用景观指数的因子分析和筛选方法研究

本文以42幅云南省一平浪林场卫星遥感图为数据源,采用相关分析、因子分析和敏感性分析等方法,对13个常用的景观指数进行了分类和筛选方法的研究.研究结果显示大多数指数间呈现极高的相关性,通过因子分析提取出了累积贡献率达82.03%的3个公因子,遂将13个景观指数分为了3大类,并利用敏感性系数筛选出了4个具有良好灵敏度、能充分反映生态学意义的代表性景观指数,即斑块个数、平均最近距离、面积加权的平均形状指数和散布与并列指数.本方法有效地解决了景观分类和评价中指数繁多冗余的问题.     

鸡魏氏梭菌的分离和鉴定

为了研究鸡魏氏梭菌的生物学特性及其发病机制,从河南某鸡场临床症状、剖检病变疑似鸡魏氏梭菌病例进行细菌分离,从中分离到1株细菌。对分离的病菌进行形态培养、生化试验、动物试验等鉴定,鉴定为鸡魏氏梭菌。药敏实验表明鸡魏氏梭菌对青霉素、庆大霉素敏感性较高。