人类宜居的汝城中部盆地气候舒适度研究

通过空气温度和相对湿度的组合确定人对周围环境感觉舒适的程度,采用舒适度列线图确定汝城县近三年逐日气候舒适程度。根据舒适程度分类标准,计算各等级的天数和各年的气候舒适期及其逐月分布状况,取三年平均值。采用Biiltner确认的日舒适有效温度等级,用日舒适有效温度计算式,计算每日逐时舒适有效温度及其持续时间。结果表明汝城县中部盆地,年气候舒适期长达196d,是目前湖南气候舒适期最长的县域。盛夏7月,昼夜24h内,夜间舒适有效温度持续长达9~16h,无极不舒适时间。适宜开展休闲度假、生态养生旅游,是人类居住的理想地域。       

几种土壤铁锰结核对Cr(Ⅲ)的氧化动力学特性

以几种土壤铁锰结核为试验材料 ,采用流动法 ,用权函数方程、抛物线方程、Elvoich方程及一级方程模型对锰矿物氧化Cr(Ⅲ )的动力学过程进行了研究 ,结果表明上述方程拟合的相关系数均达到显著水平 (P <0 .0 5 ) ,并且以权函数方程和抛物线方程拟合所得的标准差较小 ,由该氧化反应先吸附再氧化的反应机理、拟合方程的特性 ,表明氧化锰氧化Cr(Ⅲ )的反应过程受Cr(Ⅲ )和Mn2 + 的扩散、氧化锰表面覆盖度等因素影响。拟合权函数的k和A值表明其反应先快后慢 ,且锰矿物类型不同 ,初始反应速率有差异 ;随着温度的升高 ,Cr(Ⅲ )的氧化速率增加。     

拮抗细菌A2菌株的鉴定及其对小麦白粉病的防治效果

为适应现代无公害农业的发展,针对小麦白粉病的防治,从保护地土壤中分离得到一株生防细菌A2。通过形态学特征、生理生化特性的观察和测定,结合16S rDNA序列分析并构建系统发育树,对菌株A2进行了初步鉴定。同时,以清水为对照,测定了菌株A2对3432品种小麦白粉病的防治效果。结果显示该菌株主要特征是菌体杆状,内生芽孢、芽孢卵圆形,革兰氏染色阳性,好氧,接触酶反应、乙酰甲基甲醇实验为阳性,能利用柠檬酸盐;该菌株与亲缘关系较近菌株B.subtilis isolate G8的同源性达99%。结合以上两点,将菌株A2初步鉴定为枯草芽孢杆菌（B. subtilis）。防效实验显示菌株A2发酵液处理最好防治效果为72.22%;无菌滤液处理最好防治效果为29.24%,与对照相比均具有显著性差异（α=0.05）。表明,拮抗菌株A2菌体与代谢产物对小麦白粉病都具有较强的防治作用,为研制型、无毒、无公害生物农药提供了依据。     

Microbial indicators for soil quality

The living soil is instrumental to key life support functions (LSF) that safeguard life on Earth. The soil microbiome has a main role as a driver of these LSF. Current global developments, like anthropogenic threats to soil (e.g., via intensive agriculture) and climate change, pose a burden on soil functioning. Therefore, it is important to dispose of robust indicators that report on the nature of deleterious changes and thus soil quality. There has been a long debate on the best selection of biological indicators (bioindicators) that report on soil quality. Such indicators should ideally describe organisms with key functions in the system, or with key regulatory/connecting roles (so-called keystone species). However, in the light of the huge functional redundancy in most soil microbiomes, finding specific keystone markers is not a trivial task. The current rapid development of molecular (DNA-based) methods that facilitate deciphering microbiomes with respect to key functions will enable the development of improved criteria by which molecular information can be tuned to yield molecular markers of soil LSF. This review critically examines the current state-of-the-art in molecular marker development and recommends avenues to come to improved future marker systems.     

频振式杀虫灯在水稻害虫防治中的应用与研究

为了提高西双版纳稻米品质,减少农药残留,科学合理的虫害防治方法是重要的解决手段之一。频振式杀虫灯是当前运用非常广泛的一种物理诱杀害虫的工具,具有广谱、高效、无污染的特点。试验设立灯控不施药区、灯控施药区、非灯控施药区和非灯控不施药区,安排随机区组试验,调查虫害发生动态,适时开展化学农药防治和跟踪测产。试验结果表明：频振式杀虫灯单灯每晚诱虫量在6.7~224 g之间,灯控不施药区、灯控施药区和非灯控施药区与非灯控不施药区相比,对水稻主要害虫稻飞虱和螟虫的防效均达到极显著水平。同时,初步掌握了频振式杀虫灯对水稻害虫的控害效果,表现在水稻虫害发生量减少、防治成本降低、水稻增产增收等方面的效益较为显著。     

Phytopathogenic fungi new for southern Anatolia,Turkey

Twenty-nine new records are reported from Turkey. The fungi species, including their macro-and microscopic features and distributions, are described. http://www.phytoparasitica.org posting July 14, 2004.     

玉米青贮与花生秧配比对奶牛瘤胃中花生秧降解特性的影响

本试验旨在研究玉米青贮与花生秧配比对奶牛瘤胃中花生秧降解特性的影响。选择4头体重、生理状态、生产性能相近,装有永久瘤胃瘘管的中国荷斯坦奶牛,分别饲喂含有玉米青贮与花生秧不同配比的全混合日粮(TMR),3种TMR中玉米青贮与花生秧的干物质(DM)配比分别为3.9∶1.0(A组)、1.2∶1.0(B组)、0.4∶1.0(C组)。试验分3期进行,依次进行A、B、C组试验。每期预试15 d,采样期4 d;共57 d。采用尼龙袋瘤胃降解技术测定花生秧在奶牛瘤胃中DM、粗蛋白质(CP)、中性洗涤纤维(NDF)和酸性洗涤纤维(ADF)的72 h瘤胃降解率,并求得目标养分的动态降解参数及有效降解率。结果表明:1)花生秧的DM在瘤胃中有效降解率为56.49%~59.62%,CP为40.45%~47.36%,NDF为33.26%~35.20%,ADF为36.31%~37.45%。2)B组DM的有效降解率显著高于C组(P0.05),极显著高于A组(P0.01);B、C组的CP有效降解率显著高于A组(P0.05)。3)B、C组的NDF快速降解部分含量显著高于A组(P0.05);3种TMR对花生秧粗NDF和ADF有效降解率无显著影响(P0.05)。由此可见,花生秧具有较高的饲用价值。本试验条件下,玉米青贮与花生秧DM配比为1.2∶1.0时,可有效提高花生秧DM和CP的瘤胃降解率。     

Short-term survival and mortality rates in a retrospective study of colic in 1588 Danish horses

Background

Outcomes of colic treatment are of great interest to clinicians, horse owners and insurers. One commonly used criterion of success is the overall short-term survival rate. This is used as to compare treatments and to measure quality of veterinary care, but may be biased by demographic or social factors such as attitudes towards animal suffering and euthanasia. The aims of this study were to 1) describe and analyse characteristics in horses with signs of colic referred to the University Hospital for Large Animals (UHLA), University of Copenhagen, Denmark over a 10-year period and 2) to compare these rates with those published in other comparable studies.

Results

The overall survival rate for colic horses over the 10-year study period was 68% (confidence intervals (CI): 66–71%; 1087/1588). In the medical group, 1093 horses, short-term survival was 87% (CI: 85–89%). Thirty one % of referred horses were given diagnoses requiring surgical intervention (CI: 29–33%). In this group 32% of the horses were euthanized before surgery (CI: 28–36%; 159/495). Of the surgical cases 27% (CI: 23-31%) were euthanized or died during surgery. Of the horses that recovered from surgery 25% died or were euthanized (CI: 19–32%; 48/189), while 75% survived to discharge (CI: 68–81%).

Conclusions

The short term survival rates of Danish horses with colic were similar or lower to those reported from other countries. Apart from variability of veterinary care, attitudes towards euthanasia vary among the countries, which may bias the outcomes. This study indicates that qualitative interview studies on owners’ attitudes towards animal suffering and euthanasia need to be conducted. Our opinion is that survival rates are not valid as sole indicators of quality of care in colic treatment due to selection bias. If the survival rates are to be compared between hospitals, techniques or surgeons, prospective studies including mutually agreed-on disease severity scores and a predefined set of reasons for euthanasia are needed.     

Stereochemistry of matairesinol formation by <Emphasis Type="Italic">Daphne</Emphasis> secoisolariciresinol dehydrogenase

Secoisolariciresinol dehydrogenase activity was detected for the first time from Daphne odora and Daphne genkwa (Thymelaeaceae), which are known to produce optically pure (+)-matairesinol. In sharp contrast, (–)-matairesinol was formed selectively over the (+)-antipode by the secoisolariciresinol dehydrogenase preparation from both D. odora callus and D. genkwa shoots.