Male Condition, Female Choice, and Extreme Variation in Repeated Mating in a Scaly Cricket, Ornebius aperta (Orthoptera: Gryllidae: Mogoplistinae)

Mating in the scaly cricket Ornebius aperta often includes the transfer of many spermatophores to individual females during extended copulatory interactions. We manipulated male condition in staged matings to determine whether this could explain variation in the number of repeated copulations seen across pairs. Males on a high nutrient diet were in good condition, were more likely to mate repeatedly, and transferred more spermatophores on average than low-diet males (in poor condition). High-diet males were more likely to produce a vibratory signal that increased female receptivity to repeated mating attempts. Courtship and copulatory interactions were always terminated by females, and in every case males had already formed a spermatophore when deserted by females. We conclude that variation in male repeated mating success may be due to female choice rather than an inability or unwillingness of low-diet males to produce spermatophores.     

西瓜炭疽病菌圆刺盘孢分生孢子产生条件的研究

为研究圆刺盘孢Colletotrichum orbiculare的分生孢子产生条件,通过改变培养基的成分、理化性状及培养条件等方法,进行了诱导产孢试验,并对所产生的分生孢子量进行测定。结果表明,C.orbiculare在西瓜茎叶煎汁培养基上25℃恒温黑暗培养30d可产生大量分生孢子,产孢量高达7.15×109个/m L。在显微镜下观察发现,病菌在西瓜茎叶煎汁培养基上和在西瓜茎秆病斑上产生的分生孢子在形态上存在差异,前者产生的分生孢子稍短和略宽,两端钝圆;而后者产生的分生孢子相对长而细,两端较尖。试验证明寄主西瓜茎叶成分对病菌分生孢子的产生具有明显促进作用。     

PCT和NT-proBNP在脓毒血症患者生存状况预测中的应用与评价

目的:探究患者降钙素原(PCT)和N端前体脑利钠肽(NT-proBNP)水平在评价脓毒血症患者生存状况的预测价值。方法:本研究于2013年6月~2015年6月期间,选择在我院治疗的脓毒血症患者81例为研究对象,根据患者纳入研究后1个月的生存状况,将所有研究对象分为存活组(55例)和死亡组(26例)。分别测定患者PCT和NT-proBNP水平,并记录患者急性生理与慢性健康状况(APACHEII)评分,通过ROC曲线探究PCT、NT-proBNP对患者生存预后评估的价值。结果:死亡组患者PCT水平及APACHEII评分均显著高于存活组,NT-pro BNP水平显著低于存活组患者(P0.05);PCT与APACHEII评分存在正相关关系(r=0.311;P0.05);NT-pro BNP水平与APACHEII评分存在负相关关系(r=-0.289;P0.05);ROC曲线显示PCT、NT-proBNP水平预测患者生存状况的敏感性(86.23%、82.01%)及特异性(80.89%、87.39%)均较高。结论:脓毒血症患者血清PCT与NT-proBNP水平在预测患者病情严重程度及生存状况方面具有重要价值。     

A fully nonlinear viscohyperelastic model for the brain tissue applicable to dynamic rates

Understanding the mechanical response of the brain to external loadings is of critical importance in investigating the pathological conditions of this tissue during injurious conditions. Such injurious loadings may occur at high rates, for example among others, during road traffic or sport accidents, falls, or due to explosions. Hence, investigating the injury mechanism and design of protective devices for the brain requires constitutive modeling of this tissue at such rates. Accordingly, this paper is aimed at critically investigating the physical background for viscohyperelastic modeling of the brain tissue with scrutinizing the elastic fields pertinent to large, time dependent deformations, and developing a fully nonlinear multimode Maxwell model that can mathematically explain such deformations. The proposed model can be calibrated using the simple monotonic uniaxial deformation of the sample extracted from the tissue, and does not require additional information from relaxation or creep experiments. The performance of the proposed model is examined using the experimental results of two different studies, which reveals a desirable agreement. The usefulness, limitations, and future developments of the proposed model are discussed in this paper.     

Decrease in preferred temperature in response to an immune challenge in lizards from cold environments in Patagonia,Argentina

In ectotherms, the likelihood of surviving an infection is determined by the efficiency of thermoregulation, the availability of a variety of thermal microenvironments, the individual's health status, and the virulence of the infective agent. Physiological and behavioral demands related to an efficient immune response entail a series of costs that compete with other vital activities, specifically energy storage, growth, reproduction, and maintenance functions. Here, we characterize the thermal biology and health status by the presence of injuries, ectoparasites, body condition, and individual immune response capacity (using phytohemagglutinin in a skin-swelling assay) of the southernmost lizards of the world, Liolaemus sarmientoi, endemic to a sub-optimal, cold environment in Patagonia, Argentina. In particular, we study the effect of a bacterial endotoxin (lipopolysaccharide; LPS-treatment) on thermoregulation. We found that the field-active body temperature (T_b) was much lower than the preferred body temperature (T_p) obtained in the laboratory. All the individuals were in good body condition at the beginning of the experiments. The phytohemagglutinin test caused detectable thickening in sole-pads at 2 h and 24 h post-assay in males and non-pregnant females, indicating a significant innate immune response. In the experimental immune challenge, the individuals tended to prefer a low body temperature after LPS-treatment (2 h post-injection) and developed hypothermia, while the control individuals injected with phosphate buffered saline (PBS), maintained their body temperature throughout the trial. In both the LPS-treatment and PBS-control individuals, BC declined during the experiment. Hypothermia may allow this southernmost species to optimize the use of their energetic resources and reduce the costs of thermoregulation in a cold-temperate environment where they rarely attain the mean T_p (35.16 °C) obtained in laboratory.     

受精环境对哺乳动物性别形成的影响

性别控制是人类很早就关心的研究领域, 许多重要的经济性状与性别有直接的关系。控制受精环境即可控制性别, 这种方法不需昂贵的仪器设备或者药品, 易实践, 可普遍应用, 其经济效益和社会效益难以估量。文章综述了受精环境对哺乳动物性别形成影响的研究进展。这些环境因素包括母体生殖道中精氨酸含量、胚胎发育过程中子宫内葡萄糖浓度、输精时卵母细胞成熟程度以及哺乳动物受孕时生殖激素的水平等方面, 为进一步开展性别控制研究积累一定的资料。     

超声波法提取剑花总皂苷工艺研究

利用超声波法,采用正交实验对剑花总皂苷提取工艺进行研究。结果表明,提取剑花总皂苷的最优条件为:粒度80目,最佳溶剂水,超声时间40 min,溶剂挥干温度80℃,料液比1:20。     

产弹性蛋白酶菌种的筛选及发酵条件优化研究

从合肥肉联厂附近的土壤和污水中分离得到19株产弹性蛋白酶菌株,初步鉴定该菌株属于假单胞菌属.经过发酵复筛有三株产酶能力超过15u/mL.实验对菌株最佳产酶发酵条件进行了优化2%干酪素、0.5%葡萄糖、0.4%酵母膏、0.2% K2HPO4、0.01% MgSO4·7H2O;起始pH值7.0;最适发酵温度为30℃;装液量为25mL/250mL;该菌株在28h左右产弹性蛋白酶的量达18u/mL.     

脂肪酶假单胞菌的分离培养及最佳产酶条件研究

以麻疯树油为唯一碳源,从以粉碎的麻疯树种子处理过的土壤中分离筛选出1株脂肪酶活性较高的菌株,初步鉴定为假单胞菌属(Pseudomonas).实验观察了碳源、氮源、无机盐及发酵工艺对产酶的影响,摇瓶发酵结果表明.该菌株最适产酶培养基的组成是(%,w/v):橄榄油2,酵母膏0.5,(NH4)2SO4 0.5,MgCl2·6H2O 0.5,最适产酶温度为30℃,最佳产酶pH为6.5,转速180r/min,发酵培养36h酶活达到最高,为14.17U/mL.本研究为以麻疯树油为原料酶法生产生物柴油奠定了一定的基础.