983 resultados para 367.224


Relevância:

10.00% 10.00%

Publicador:

Resumo:

通过分析咖啡旋皮天牛 Acalolepta cervinus (Hope)和咖啡灭字虎天牛 Xylotrechus quadripes Chevr.的生态对策、种间竞争策略,并结合有害生物综合管理(IPM)理论、咖啡林生态系统的特性、咖啡天牛的发生特点,提出了咖啡天牛的防治策略。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

探讨了P16蛋白和生精细胞凋亡在热压和11酸睾酮诱导恒河猴无精子症和少精子症中作用间的关系。3^末端标记分析(TUNEL)结果显示热应激和超生理剂量睾酮能够诱导生精细胞出现凋亡信号,它分别于处理后d5和d30达到最强。免疫组化结果显示,热压或TU主要诱导精原细胞和其它生精细胞以及Sertoli细胞P16的表达。P16蛋白的表达在生精细胞凋亡晚期,即隐睾手术d10或注射TUd60后迅速升高并维持高表达,该蛋白在生精细胞凋亡晚期可能通过抑制精原细胞的有丝分裂,扰乱正常的精子发生。

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The first three reports in this series (Parts I, II and III) deals with binders and technologies used in stabilisation/ solidification (S/S) practice and research in the UK. This first part covers 'basic principles'while the second covers 'research' and the third 'applications'. The purpose of this work, which forms part of the Network STARNET on stabilisation/solidification treatment and remediation, is to identify the knowledge gaps and future research needs in this field. This paper describes the details and basic principles of available binders and technologies in the UK. The introduction in the report includes background on S/S, legislation aspects, overview of STARNET and its activities and details of commonly used binder selection criteria. The report is then divided into two main sections. The first covers binders and includes cement, blastfurnace slag, pulverised fuel ash, lime, natural and organophilic clays, bitumen, waste binders and concludes with proprietary binders. The second part details implementation processes for S/S treatment systems starting with ex-situ treatment systems, such as plant processing, direct mixing and in-drum processing and finishes with in-situ treatment processes, such as mechanical mixing and pressure mixing. © 2005 Taylor & Francis Group.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

The reproductive traits of Gymnocypris selincuoensis from Selincuo Lake and its tributaries were investigated in 1997 and 1998. The youngest mature male was age 7 with a standard length (SL) of 172.0 mm, and the youngest mature female was age 8 with a SL of 194.0 mm. The L(50)s Of SL and age at first maturity were respectively 250.32 mm and age 9 for males and 224.71 mm and age 8 for females. The gonadosomatic index (GSI) significantly changed with seasons for mature individuals but not for immature individuals. GSIs of mature females at stages IV and V of ovary development increased with SL and reached a maximum value at the SL range from 370 mm to 390 mm; the GSIs of mature males were negatively correlated with SL. The breeding season lasted from early April to early August. Egg size did not significantly change with SL but increased with the delay of spawning. The individual absolute fecundity varied from 1,341 to 28,002 eggs (mean 12,607+/-7,349), and the individual relative fecundity varied from 6.4 to 42.0 eggs.g(-1) (mean 25.5+/-9.7). The individual fecundity increased with total body weight; it also increased with SL for those of SL less than 370 mm. There was a rest of spawning for mature individuals.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

A chymotrypsin inhibitor, designated NA-CI, was isolated from the venom of the Chinese cobra Naja atra by three-step chromatography. It inhibited bovine (x-chymotrypsin with a K-i of 25 nM. The molecular mass of NA-CI was determined to be 6403.8 Da by matrix-assisted laser-desorption ionization time-of-flight (MALDI-TOF) analysis. The complete amino acid sequence was determined after digestion of S-carboxymethylated inhibitor with Staphylococcus aureus V8 protease and porcine trypsin. NA-CI was a single polypeptide chain composed of 57 amino acid residues. The main contact site with the protease (PI) has a Phe, showing the specificity of the inhibitor. NA-CI shared great similarity with the chymotrypsin inhibitor from Naja naja venom (identities = 89.5%) and other snake venom protease inhibitors. (C) 2003 Elsevier Inc. All rights reserved.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

From modelling to manufacturing, computers have increasingly become partners in the design process, helping automate many phases once carried out by hand. In the creative phase, computational synthesis methods aim at facilitating designers' task through the automated generation of optimally directed design alternatives. Nevertheless, applications of these techniques are mainly academic and industrial design practice is still far from applying them routinely. This is due to the complex nature of many design tasks and to the difficulty of developing synthesis methods that can be easily adapted to multiple case studies and automated simulation. This work stems from the analysis of implementation issues and obstacles to the widespread use of these tools. The research investigates the possibility to remove these obstacles through the application of a novel technique to complex design tasks. The ability of this technique to scale-up without sacrificing accuracy is demonstrated. The successful results confirm the possibility to use synthesis methods in complex design tasks and spread their commercial and industrial application.

Relevância:

10.00% 10.00%

Publicador:

Resumo:

This study investigates the structural behavior of precracked reinforced concrete (RC) T-beams strengthened in shear with externally bonded carbon fiber-reinforced polymer (CFRP) sheets. It reports on seven tests on unstrengthened and strengthened RC T-beams, identifying the influence of load history, beam depth, and percentage of longitudinal steel reinforcement on the structural behavior. The experimental results indicate that the contributions of the external CFRP sheets to the shear force capacity can be significant and depend on most of the investigated variables. This study also investigates the accuracy of the prediction of the fiber-reinforced polymer (FRP) contribution in ACI 440.2R-08, UK Concrete Society TR55, and fib Bulletin 14 design guidelines for shear strengthening. A comparison of predicted values with experimental results indicates that the guidelines can overestimate the shear contribution of the externally bonded FRP system. © 2012, American Concrete Institute.

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador:

Relevância:

10.00% 10.00%

Publicador: