拮抗放线菌B1菌株鉴定及其防治番茄灰霉病的初步研究

为明确放线菌B1菌株在植物病害生物防治中的应用潜力,采用平板对峙培养法、离体叶片和果实及温室盆栽苗测定其抑菌作用,通过多相分类法研究其分类地位,并且采用单因子试验与正交试验相结合的方法,筛选出该菌株的液体发酵培养基配方.结果表明:菌株B1对10种植物病原真菌和3种植物病原细菌有抑制作用,其中对番茄灰霉病菌、番茄早疫病菌、小麦纹枯病菌、甘蓝黑腐病菌和西瓜果腐病菌的抑制作用较强,对番茄灰霉病菌的生长抑制率达86.25%;菌株B1的代谢产物对番茄灰霉病菌菌丝有致畸作用;菌株B1发酵上清液在离体叶片和活体植株上对番茄灰霉病具有良好的生防作用,其防治效果分别为68.80%和64.03%.根据形态特征、培养性状、生理生化特性和16S rDNA序列分析结果,将菌株B1初步鉴定为淡紫灰链霉菌Streptomyces lavendulae.通过正交试验筛选出菌株B1的液体发酵培养基组成为:葡萄糖15 g、玉米浆20g、NH4H2PO40.5 g、MgSO41.0 g、自来水1 000mL,pH 7.2～7.4.     

河南省部分地区鸡志贺氏菌病病原分离鉴定及药敏试验

为了对河南省部分地区鸡志贺氏菌病的病原进行分离鉴定和药物敏感性调查,对河南省6个地区的鸡腹泻病病料进行了细菌学检查,经细菌分离培养、形态染色镜检、生化试验和动物试验,共分离鉴定出12株鸡源志贺氏菌。血清学试验结果显示,分离菌株存在种和型的差异,其中8株为福氏志贺氏菌,3株为鲍氏多价志贺氏菌,1株为痢疾Ⅱ型志贺氏菌。动物试验结果表明,分离的12株鸡志贺氏菌均具有致病性,且毒力不同,其中,从三门峡分离的菌株有很强的毒力,发病率和死亡率均为100%。药敏试验结果显示,大多数鸡志贺氏菌对氨苄/舒巴坦和阿米卡星较为敏感,对其他药物具有严重的耐药性,且不同地区分离的鸡志贺氏菌对药物的敏感性不同。     

长白落叶松初级种子园优树子代测定及优良家系的选择

对长白落叶松初级种子园优树子代测定林(19年生)37个家系的树高、胸径和立木材积进行分析的结果表明:树高、胸径、材积均差异极显著,且生长性状之间呈显著正相关关系。以材积性状作为主要指标,同时兼顾树高、胸径指标,对参试家系进行选择,选出10个优良家系。     

可凝气体组分对涡流管能量分离效率的影响分析

应用1952～2008年我国宏观农村居民消费和GDP数据,通过协整模型分析方法针对农民消费对GDP增长的促进作用进行实证分析。结果表明,农民消费与GDP增长在长期内稳定地存在着协同互动的均衡关系,并且二者互为格兰杰因果关系。通过协整模型发现,长期内,农村居民消费增长1%,我国GDP就会增长1.7483%,其对经济增长的促进作用较大。     

大学英语语音量具的设计与质量分析

如何有效、准确地测量大学英语学习者的语音能力是大学英语教学中一个十分值得研究的课题。基于构建和完善我国大学英语语音测试体系的目的而创制的一套英语语音测量工具,以元素法为设计方法,由接受性英语语音测试和产出性英语语音测试构成,考察受试者的接受性英语音段、超音段能力及产出性英语音段、超音段能力。通过具体预测、题项分析、题项筛选、正式测试、信度和效度分析等诸多环节的操作,证明这一量具具有一定的科学性和可操作性。     

重组人乳铁蛋白对原代肝、肾细胞的毒性研究

[目的]通过模拟肝、肾毒性的体外细胞试验,研究重组人乳铁蛋白是否对小鼠原代肝肾细胞具有毒性作用,为其进一步的安全性评价提供依据。[方法]采用模拟体外消化试验所得的重组人乳铁蛋白消化产物及重组人乳铁蛋白为受试物,牛乳铁蛋白为对照,以小鼠原代肝、肾细胞为平台,用MTT法检测受试物对细胞活性的半数抑制浓度（IC50）,研究细胞毒性剂量-反应关系。[结果]在设定的试验条件下,未发现重组人乳铁蛋白对肝肾细胞存在靶毒性,结果能与已进行的亚慢性毒性试验相互印证。[结论]为对重组人乳铁蛋白的进一步安全性评价及其他转基因食品的安全性评价方法提供了参考。     

Acoustic emission behavior of shale under four point bending test

PXWAE Acoustic Emission System is useol to investigate the acoustic emission behavior of shale under four point bending test. In these tests, the maximum bending stress, bending strain, acoustic emission hits, acoustic emission energy and etc., are recorded. The results show that when vertical loads impose on the shale sample which has horizontal stratification planes, Kaiser effect does exist under four point bending tests. Kaiser point can be recognized directly from the stress vs. cumulative AE hits curve. But by the impact of shale’s stratifications and local failure during the tests, strain relaxation occur which makes it difficult to determine the Kaiser point only by the strain vs. acoustic emission curve. An accurate conclusion can be achieved by a comprehensive judgment combing with all test data, as well as the failure mode of rock sample. The research on acoustic emission behavior of rock in the stress state during bending tests to some extend can provide guidance to engineering practice for stability monitoring of mine roof or separation layer with acoustic emission monitoring technology.     

Tidal Breathing Flow‐Volume Loop Analysis for the Diagnosis and Staging of Tracheal Collapse in Dogs

Background: Tracheoscopy is generally used for the diagnosis of tracheal collapse (TC) in dogs; yet, it is costly, requires anesthesia, and can irritate the airway. The tidal breathing flow‐volume loop (TBFVL) is a safe, quick, and noninvasive pulmonary function test currently used in humans. Hypothesis: TBFVL will differentiate dogs with TC from healthy controls and contribute to disease grading. Animals: Twenty‐eight dogs with naturally occurring TC and 10 healthy controls. Methods: Cross‐sectional, prospective clinical study: The 38 dogs were assigned to one of 4 groups based on tracheoscopy results: group A (n = 10, healthy controls), group B (n = 10, grade I TC), group C (n = 10, grade II TC), and group D (n = 8, grade III TC). The TBFVL measurement was performed on all dogs and loops were assessed for their shape. Forty‐four TBFVL parameters were calculated. Results: Two types of TBFVL shapes were identified: Type I, representative of the 10 healthy controls, and Type II, representative of the 28 dogs with TC. Statistical analysis showed the dogs could be differentiated into healthy or affected by TC by 3 indices, TE/TI (expiratory time divided by inspiratory time), TI/TTOT (inspiratory time divided by total respiratory time), and EF75/IF75 (expiratory flow at end tidal volume plus 75% end tidal volume divided by inspiratory flow at end tidal volume plus 75% end tidal volume). The TC could also be graded as mild‐moderate (grades I and II) or severe (grade III), showing a diagnostic value of 97.4%. Conclusion and Clinical Importance: TBFVL is accurate, quick, noninvasive, and safe and can contribute to the diagnosis of TC in dogs.     

粗粒料抗剪强度和颗粒破碎大型三轴试验研究

试验材料采用原料场颗粒级配进行缩尺制备,通过大型三轴试验对同一种试样在饱和与干燥的试验条件下进行对比分析,得到干燥试样的内摩擦角大于饱和试样的内摩擦角;且试样的φ0（当围压与大气压比值为1时的妒值）也存在相同的变化规律;干燥试样的颗粒破碎率小于饱和试样的颗粒破碎率;表明对于同一种试样,不同的试验条件对颗粒破碎有一定的影响。