田块尺度上土壤重金属污染地统计分析及评价(简报)

该文以北京市某生态农场的大田为例,应用地统计学分析方法进行了变异函数的计算和模型拟合,建立了计算土壤重金属含量的最适空间插值理论模型,随后运用克立金估值方法绘制了田块尺度上土壤重金属的空间分布图,并与土壤重金属污染标准进行比较,土壤重金属污染评价结果表明：研究范围内的土壤重金属含量较低,未发现污染。该研究结果表明地统计学分析方法可为田块尺度上的农业优化管理提供决策支持。     

大熊猫分布区近半个世纪逐日气温空间插值分析

目的高时空分辨率的气温分布是准确模拟物种适宜分布区的基础。大熊猫分布区是全球35个生物多样性热点区之一，属于典型山地地形。方法为了有效消除海拔效应在气温空间插值中的误差，本研究基于线性递减率调整法(linear lapse rate adjustment, LLRA)对大熊猫分布区42个气象站点1960—2010年的日最高气温(daily maximum temperature，dT_max)、日最低气温(daily minimum temperature，dT_min)和日平均气温(daily mean temperature，dT_mean)进行了空间插值，评估了LLRA插值法的准确度，并分析了近半个世纪大熊猫分布区气候变暖的格局。结果结果表明，使用LLRA法校正误差的局域递减率插值，准确度明显高于全球平均递减率和初步局域递减率；大熊猫分布区将近90%的区域dT_max、dT_min和dT_mean同时显著上升，上升最快的地区主要集中在秦岭和岷山西北部；dT_max、dT_min和dT_mean显著上升的中位速度分别为每100年上升1.68、2.32和1.77 ℃，超过3/4的区域dT_min上升速度大于dT_max；在气象站点代表的低于3 500 m的海拔范围内，dT_min和dT_mean的变化速度随海拔上升表现出显著增加趋势，且dT_min的上升趋势大于dT_mean。结论本研究证明了LLRA法能有效消除海拔效应在气温空间插值时造成的误差，提高山地气温空间插值的准确度。研究发现，大熊猫分布区近半个世纪经历了显著变暖，由LLRA插值获得的逐日气温分布图可为进一步评估变暖对大熊猫分布区珍稀濒危物种的分布影响、制定相应的保护规划提供基础。      

阻燃杨木胶合板挥发性有机化合物释放研究

选取四种品牌四种厚度阻燃杨木胶合板,待其释放稳定（第28天）,采用小型环境舱采集其挥发性有机化合物（VOCs）,并结合气相色谱-质谱法,分析挥发性有机化合物种类和含量.实验结果表明：不同品牌阻燃杨木胶合板总挥发性有机化合物（TVOC）释放量在50.14μg/m3 ～ 248.92μg/m3之间;各个板材VOCs释放量和检出物不完全相同,单个板材检出物种类最高为36种;芳香类和烃类化合物质量浓度之和占挥发性有机化合物总质量浓度的55.10％～85.72％;同时还捡出醛类、酮类和酯类等其他挥发性有机化合物;经过磷-氮-硼系阻燃剂处理的板材VOCs释放量比磷-氮系阻燃剂处理板材高;同种品牌阻燃杨木胶合板随厚度增加TVOC释放量呈增加趋势.     

一起猪群腹泻的紧急流行病学调查

2020年1月3日,某猪场部分生猪出现腹泻症状,3 d后达发病高峰,波及全场,并伴有部分生猪死亡,袭击率为60.66%,病死率为6.88%。为探寻病因,采取现场调查与实验室检测相结合的方式,对此次猪群腹泻进行了调查,综合推断此次暴发是由大肠杆菌、沙门氏菌、志贺氏菌引起的细菌性腹泻及由应激因素引起的应激性腹泻,饮入污水、断水应激、寒冷应激是导致本次猪群腹泻的主要原因。据此,提出了拌料饲喂抗生素、清洗消毒圈舍和饮水设施、强化饲养管理等干预措施,并有效控制了疫情。调查提示,加强饲养管理,减少寒冷、缺水引起的应激,保持清洁饮水,对预防猪群腹泻具有十分重要的意义。     

抗虫棉品种苏棉6039的选育

介绍了苏棉6039的选育过程和方法、特征特性以及栽培技术要点。     

涉农类高职专业顶岗实习学习共同体构建研究

涉农类高职专业顶岗实习具有"行业相对集中、企业相对分散"的特殊性,实习岗位过于分散很难进行有效的指导和管理。实践证明:以"学习共同体"建设统筹顶岗实习的全过程,系统设计顶岗实习方案是提高涉农类高职专业顶岗实习质量的有效途径。     

重症肌无力病情严重程度对尿动力学参数的影响

目的探讨眼肌型(Ⅰ型)及全身型(Ⅱ型)重症肌无力(myasthenia gravis,MG)患者尿动力指标的差异,为临床治疗重症肌无力提供参考。方法分别检测8例眼肌型及15例全身型MG患者尿动力学指标,分析组间尿动力参数差异及组间各指标异常人数构成比差异。结果全身型MG患者最大尿流率显著低于眼肌型患者(P0.05);全身型MG患者最大尿流率异常人数比率显著高于眼肌型患者(P0.05),而膀胱收缩力增强人数显著低于眼肌型患者(P0.05);全身型MG患者初始尿意、残余尿量异常比率及膀胱出口梗阻发生率均高于眼肌型患者,但差异无显著性(P0.05);女性MG患者膀胱收缩增强人数显著高于男性(P0.01)。结论全身型MG患者最大尿流率异常人数显著高于眼肌型,MG病情加重可能会伴发尿动力异常,临床诊疗应加以重视。     

Characterization of integrons-mediated antimicrobial resistance among Escherichia coli strains isolated from bovine mastitis

To assess the prevalence of antimicrobial resistance and class I integrons in Escherichia coli strains (n=58) isolated from bovine mastitis in Inner Mongolia, antimicrobial susceptibility and the presence of various types of integrons were characterized. Most isolates were susceptible to amikacin, colistin, ceftazidime, gentamicin and kanamycin, while those also exhibited high resistant incidence rates to ampicillin, amoxicillin, sulfadiazine and sulfamethoxydiazine. The integrase gene of integrons was amplified by PCR using degenerate primers. The integrons were confirmed by restriction fragment length polymorphism (RFLP) analysis of positive PCR products. Neither class II nor class III integron was detected, while 56.90% (n=33) of the isolates were positive for the presence of intI1 gene. Sequencing analysis of gene cassettes revealed that seven gene cassettes were found, which encoded resistance to trimethoprim (dfrA1 and dfrA17), aminoglycosides (aacA4, aadA1 and aadA5) and chloramphenicol (catB3), respectively. Of them, the gene cassette array dfrA17-aadA5 was found most prevalent (62.96%). The percentage of positive-integron among the isolates whose resistant profile was relatively broad (n> or =7) is 100.00%, while the one in narrow-profile isolates (n=2-6) is 30.56%. The correlation analysis revealed the incidence of integrons among the isolates were highly related to the resistant profile, indicating integrons play an important role in the dissemination and spread of the antimicrobial resistant strains.     

Fatal infection in human flora-associated piglets caused by the opportunistic pathogen Klebsiella pneumoniae from an apparently healthy human donor

Seventeen out of 24 human flora-associated (HFA) piglets died after oral administration of whole fecal flora from an apparently healthy human donor. The bacteria isolated from the organs of the infected piglets were identified as Klebsiella pneumoniae by bacteriological and biochemical tests and 16S rRNA gene sequence analysis. The identical K. pneumoniae strain was also isolated from the donor's fecal flora. All three neonatal piglets inoculated with K. pneumoniae from the donor's fecal flora developed severe diarrhea, with 2 eventually dying. This strongly suggests that the opportunistic pathogen K. pneumoniae from the human donor caused the fatal infection in the HFA piglets. The results underscore the importance of safety evaluation of the human donor's fecal flora for HFA piglet development.     

牦牛血液矿物元素含量和血清指标变化规律的研究

为了探讨牦牛营养代谢疾病的病因,在黄河首曲草地对放牧牦牛血液矿物元素含量和血清指标的变化规律进行了系统的研究。结果表明:牦牛血液矿物元素含量和血清指标具有明显的季节动态;在首曲草原,牧草矿物元素含量季节性缺乏是引起牦牛营养代谢疾病的原因之一。