玉米秸秆还田对盐碱地土壤真菌多样性的影响

为揭示盐碱地秸秆还田改良中土壤真菌群落结构及其多样性变化,以未开垦盐碱地(ZH1)、非盐碱连作玉米田(ZH2)和秸秆还田盐碱玉米田(ZH3)为材料,在玉米吐丝期,利用高通量测序技术与相关生物信息学分析结合,研究表层土壤真菌群落丰富度、多样性和群落结构的变化。结果表明,3个处理土壤真菌群落结构和丰度差异大,已知菌属中ZH1的优势属为马拉色菌,ZH2优势属为暗球腔菌属,ZH3优势属为链格孢属。玉米秸秆还田对盐碱地土壤真菌多样性的影响较大,两年玉米秸秆还田盐碱土壤真菌多样性和物种丰度与未开垦盐碱地比较均有所下降。     

Dynamics of Follicular Fluid in One‐humped Camel (Camelus dromedarius)

In the present study, ovarian follicular fluid and serum biochemical, hormonal, electrolytes and amino acids profiles in female dromedary camel (Camelus dromedarius), were investigated. Fluid from small (2–6 mm) and large follicles (7–20 mm) and blood samples were collected from 25 clinically healthy adult female camels. The concentrations of glucose, cholesterol, triglycerides, high‐density lipoproteins, urea, total proteins, albumin, globulin, fibrinogen, alanine aminotransferase, aspartate aminotransferase and tri‐iodothyronine were lower (p ≤ 0.05) in large follicles when compared with the small follicles. However, the concentrations of low‐density lipoproteins, uric acid, creatinine, alkaline phosphatase and acid phosphatase in small and large follicles did not differ. The concentrations of oestradiol 17‐β and progesterone were higher (p ≤ 0.05) in large follicles. The serum concentrations of these hormones were many folds lower (p ≤ 0.05) than those of follicular fluid. Among electrolytes, the concentration of phosphorus was higher (p ≤ 0.05) in the large follicles, while that of potassium and chloride were lower (p ≤ 0.05) in the small follicles. Serum concentrations of sodium, chloride, calcium and phosphorous were higher (p ≤ 0.05), while that of potassium lower (p ≤ 0.05) than corresponding concentrations in the follicular fluid. The concentrations of leucine and arginine were higher (p ≤ 0.05) in follicular fluid when compared with serum concentrations, while the reverse was true for other amino acids. In conclusion, this study is indicative of either low or high concentrations of certain biochemical metabolites, hormones, electrolytes and amino acids in small and large follicles for the individual roles that they play in the growth and development of follicles in the one‐humped she‐camel.     

木材缺陷图像的灰度形态滤波

介绍数学形态学中的灰度形态滤波方法,给出对木材缺陷图像进行闭、开运算处理后的仿真图像实例,利用木材缺陷图像截面灰度分布对处理效果进行分析.结果表明:采用灰度形态滤波方法对木材缺陷图像进行滤波处理,可有效去除木材缺陷图像中的噪声,改善图像的视觉效果,提高后期缺陷边缘检测的精确度,从而证明该方法对木材缺陷图像进行滤波处理是可行的.     

遥控自动立木整枝机电源控制系统

便携式遥控自动立木整枝机控制系统电源的使用效率是整个系统的一个重要指标及可靠工作的前提.该文在分析控制逻辑的基础上,从节能的观点出发,合理地研制了自动立木整枝机发射与接收系统电源控制电路.电源供电能力测试的结果证明:该电源控制电路可以有效地提高整个系统电源的效率,能够很好地满足自动立木整枝机的工作需要.      

基于高温诱发树木多倍体的模糊PID温度控制器

针对树木枝芽的室外高温诱发多倍体处理,介绍了一种模糊PID温度控制器,该控制器具有显示温度、设定温度、自动控制温度等功能。控制器采用PID参数模糊自整定方法,充分发挥了其动态响应好、上升时间快、超调小的特点,具有较高的动态跟踪品质和稳态精度,并在实际应用中取得了较好的控制效果。     

Salmonella in captive and wild Tasmanian devils (Sarcophilus harrisii) in Tasmania

Translocation of Tasmanian devils (Sarcophilus harrisii) is a common strategy for recovery of the species as carried out by the Save the Tasmanian Devil Program. Dasyurids including the endangered Tasmanian devil are well known to asymptomatically harbour the zoonotic bacteria Salmonella enterica in their intestinal tracts. Testing for Salmonella is a routine component of pretranslocation health testing, so a statewide microbiological survey of captive and wild devils was implemented in order to understand prevalence and common Salmonella serotypes, and inform decision-making when positive cultures are identified. This preliminary study identified a significantly higher proportion of Salmonella isolations in wild compared with captive devils. Mississippi and Typhimurium were the most common serotypes, followed by Lexington, Bovismorbificans, Kottbus and Amsterdam. Given the common finding of Salmonella in wild devils and the range of serotypes involved, in addition to numerous isolations in domestic species and humans, it is unlikely that the release of small numbers of captive devils to the wild in Tasmania poses a significant risk to the destination ecosystem. Ongoing monitoring of devils is required as the stress of acclimatisation could predispose devils to clinical disease. Appropriate personal protective attire is pertinent to protect personnel handling animals from this zoonotic infection.     

Pulmonary mycobacteriosis caused by Mycobacterium intracellulare in a Tasmanian devil (Sarcophilus harrisii)

The health of captive Tasmanian devils (Sarcophilus harrisii) is currently of increased interest because wild populations are being decimated by the spread of devil facial tumour disease. This report describes the pathology of an aged captive Tasmanian devil that had a pulmonary mycobacterial infection caused by Mycobacterium intracellulare in addition to multiple neoplastic processes.     

青南高海拔地区高寒草甸植物群落多样性的研究

根据 42个样地的实地调查资料 ,采用不同的物种多样性指数、丰富度和均匀度测度指标对达日县建设乡高海拔地区高寒草甸的物种多样性进行了分析 ,结果表现为 :草地物种多样性随海拔的升高总体上呈现下降的趋势 ;“黑土滩”物种多样性指数、丰富度和均匀度指数最低 ,草地生物量也最低。苔草、嵩草和灌丛草甸 ,有着较高的物种多样性指数、丰富度和均匀度指数。单子叶和灌丛植物生物量随海拔梯度的变化较为复杂 ,在一定海拔范围内有较高的生物量。双子叶植物生物量随海拔的升高基本呈现下降趋势