Reliability Analysis Based on a Nonlinear Fatigue Damage Accumulation Model

A modified nonlinear fatigue damage accumulation model based on the Manson-Halford theory was presented,and the new model was developed for fatigue life prediction under constant and variable amplitude loading, which took the effects of the load interactions and the phenomenon of material＇s strength degradation into account. The experimental data of the 30 Cr Mn Si A and the LY-12 cz from literature were used to verify the proposed model. And from the good agreement between the experimental data and predicted results,we can see it clear that the proposed method can be applied to predicting fatigue life under different loadings.     

You are what you eat: native versus exotic Crotalaria species (Fabaceae) as host plants of the Ornate Bella Moth,Utetheisa ornatrix (Lepidoptera: Erebidae: Arctiinae)

Crotalaria plants and Utetheisa ornatrix are closely linked to each other: the larvae destroy the seeds, while the moth depends on hostplants for alkaloids. To better understand the ongoing co-evolution, the present study examines how native hostplants compare to exotic ones. Leaf-feeding on Crotalaria pumila, C. rotundifolia, and C. incana, native to the moth’s range, led to faster larval development than on the exotic C. lanceolata, C. spectabilis, and C. pallida. Seed-feeding on all species of Crotalaria led to accelerated larval development and a resultant larger adult moth, and correlates with a higher nitrogen content in the plant tissues. These results add a novel dimension to the previous studies of reproductive biology of this model organism. In controlled settings, mature larvae showed preference for leaves of C. spectabilis over those of other species, perhaps due to the higher alkaloid content. Differences in morphology and phenology of Crotalaria determine the ecology of U. ornatrix populations in Florida. The introduction of novel hostplants, on which U. ornatrix can have a significant negative effect and which are of concern to humans as invasive toxic weeds, has greatly expanded the niche occupied by this moth. Possible co-evolution of Utetheisa sensu lato and plant defences in the genus Crotalaria is discussed.     

超滤质谱法研究人血清白蛋白与甘草提取物的相互作用

为研究和筛选甘草提取物中的活性成分,采用超滤质谱法(UF-MS)研究了人血清白蛋白和5种甘草提取物(甘草苷、甘草酸、甘草素、甘草呋喃酮和甘草利酮)的相互作用.结果表明:这5种甘草提取物均与人血清白蛋白有不同程度的结合,其中甘草酸的结合能力最强,其次是甘草苷、甘草素、甘草呋喃酮和甘草利酮.说明超滤质谱法可准确识别与受体蛋白质结合的活性小分子配体,实现天然产物活性成分的快速筛选.     

Label-free and real-time detection of specific binding of IgG proteins by oblique-incidence reflectivity difference method

The entire interaction process between anti-mouse immunoglobulin-G (IgG) and mouse IgG with a concentration range from 1 to 0.25 mg/mL has been label-free detected by the oblique incidence reflectivity difference (OIRD) method.We achieved the two-dimensional scanning images of OIRD Re{△ p △s } intensities before and after interactions as well as the curves of reaction dynamic processes.The experimental results suggest that OIRD method not only can label-free distinguish the different concentrations of proteins and detect biological microarrays,but also can real-time monitor the kinetic processes of biomolecular interactions.     

Indirect and direct acoustic aggression in cicadas: first observations in the Palaearctic genus Tibicina Amyot (Hemiptera: Cicadomorpha: Cicadidae)

Tibicina Amyot is a cicada genus of the Palaearctic biogeographical region with seven taxa (species and subspecies) distributed in France. As in other cicadas, the sound production by tymbal vibration is restricted to males. In Tibicina, males are attracted by conspecific calling songs and tend to form groups of several individuals which maintain a minimal distance between each other. Observations based upon male–male interactions in such aggregations and on some preliminary experiments conducted with males kept in captivity revealed for the first time both indirect and direct aggression. Spacing and chorusing are interpreted as a by-product of indirect aggression mediated through the calling song. Direct aggression occurred when spacing is not respected. It is achieved through a ritualistic sequence that involves mainly the production of the rivalry song, an acoustic signal previously reported in the literature for two cicada species only. In addition, satellite males and male–male courting are reported. These preliminary results suggest that the sound social organization in the genus Tibicina is more elaborate than first suspected and should be reconsidered in terms of lek behaviour and sexual selection.     

镓(Ⅲ)—水杨醛氨基酸Schiff碱配合物与DNA的相互作用研究

应用紫外-可见光谱、循环伏安法和粘度法研究了3个镓(Ⅲ)—水杨醛氨基酸Schiff碱配合物(GaL2,GaLbipyCl,GaLphenCl,L为水杨醛谷氨酸Schiff碱,bipy为2,2'-联吡啶,phen为1,10-邻菲啰啉)与DNA分子的键合作用.紫外-可见光谱表明配合物与DNA发生插入作用;循环伏安法表明GaLbipyCl与DNA的作用涉及沟槽或静电结合方式,GaL2和GaLphenCl与DNA发生嵌入作用;粘度法表明配合物与DNA以沟槽模式或部分插入的方式结合.综上所述,推测3个配合物以沟槽模式或部分插入的方式与DNA结合.     

癌症相关促凋亡蛋白Par-4的信号转导途径预测研究

利用支持向量机(SVM)技术构建Par-4关联的蛋白质相互作用网络,预测出与Par-4有相互作用的蛋白质82个;这些蛋白质按照功能划分为8大类,主要包括:蛋白激酶、泛素化蛋白酶、死亡受体相关因子、与细胞周期或DNA复制相关蛋白质、调节蛋白质、与疾病相关蛋白质、具有特定结构域结合蛋白质和其他蛋白质等。结合文献挖掘和数据库检索信息,推断出了Par-4的2条可能新的信号转导途径。首次预测到Par-4与一大类泛素化蛋白有密切的关系。研究发现,Par-4与多种蛋白质具有复杂的相互作用,并且,在多个细胞凋亡途径中扮演了重要角色。     

丹参植株邻苯二甲酸与立枯丝核菌菌丝生长互作研究

为探讨导致丹参连作障碍的邻苯二甲酸与立枯丝核菌菌丝生长的相互作用，采用气相色谱法确定邻苯二甲酸的来源；通过室内菌丝生长抑制实验，研究邻苯二甲酸对立枯丝核菌菌丝生长的作用及临界浓度；采用高效液相色谱法测定菌丝生长抑制实验中培养体系在菌丝生长前后邻苯二甲酸含量的变化。结果显示：丹参植株地上部含有6种邻苯二甲酸酯类成分，总相对含量为8.264%；地下部含有5种邻苯二甲酸酯类成分，总相对含量为1.069%；邻苯二甲酸浓度对立枯丝核菌菌丝的生长存在低浓度促进，高浓度抑制的作用方式，在其浓度为0.1 mg/mL时，立枯丝核菌菌落数最多且菌落直径最大。在相同培养条件下，邻苯二甲酸的加入促进了立枯丝核菌生长繁殖，但其含量没有降低，证明邻苯二甲酸不是给立枯丝核菌生长提供碳源，而是起到相当于催化剂的作用。该研究旨在为克服丹参连作障碍提供新方法和理论依据。     

消费者交互作用对网络效应产品扩散的影响——基于产品生命周期的视角

从消费者采用产品过程的生命周期(PLC)视角出发,运用微观扩散模型仿真分析消费者交互作用对网络效应产品扩散的影响.研究表明:消费者交互作用所产生的局部网络效应能够加快产品扩散早期和中期速度,而聚集效应则会降低产品扩散中期速度; 消费者之间交互强度越强,产品扩散中期速度越快; 全局交互型消费者则会降低产品扩散早期速度,但能提高产品扩散中期速度;且上述因素对网络效应产品PLC不同阶段扩散速度的影响还会由于消费者交互作用所形成的复杂社会网络结构差异而呈现不同模式.这些研究结论能够为网络外部性市场中企业的营销策略提供一定新启示.     

Biological characterization of the obligate symbiosis between Acropyga sauteri Forel (Hymenoptera: Formicidae) and Eumyrmococcus smithii Silvestri (Hemiptera: Pseudococcidae: Rhizoecinae) on Okinawa Island,southern Japan

The ant Acropyga sauteri Forel has an obligate, mutualistic symbiosis with a mealybug, Eumyrmococcus smithii Silvestri, on Okinawa Island, southern Japan. The mealybugs live inside ant nests nearly all their lives, and the ants depend on them for food. Alate foundress queens carry mealybugs during their nuptial flights, using them to establish new colonies at new sites. However, important aspects of the symbiosis have not yet been elucidated. The present study characterizes the basic biology of the symbiosis and describes for the first time the morphologies of all growth stages of E. smithii. Our study suggests that E. smithii has only one nymphal stage, followed by a female pupal stage or male prepupal stage. Intensive sampling of ant nests across seasons showed that A. sauteri prefers nest sites 5–20 cm underground. Acropyga sauteri produced reproductive stages mainly in mid‐March or early April, and numbers of both ant workers and mealybugs increased from spring to summer. Experimental determination of colony identity with a method using nestmate recognition by ants suggested that each ant colony rarely has a perimeter greater than 30 cm, that the ants are monogynous, and that different ant colonies are densely aggregated along the root system of a plant, adjacent to each other but not interflowing. Both symbiotic partners were vulnerable to attacks by several common subaerial ant species following physical disturbance to their nests.