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101.
102.
Hu Z  Xia Y  Guo X  Dai J  Li H  Hu H  Jiang Y  Lu F  Wu Y  Yang X  Li H  Yao B  Lu C  Xiong C  Li Z  Gui Y  Liu J  Zhou Z  Shen H  Wang X  Sha J 《Nature genetics》2012,44(2):183-186
Non-obstructive azoospermia (NOA) is one of the most severe forms of male infertility. Its pathophysiology is largely unknown, and few genetic influences have been defined. To identify common variants contributing to NOA in Han Chinese men, we performed a three-stage genome-wide association study of 2,927 individuals with NOA and 5,734 controls. The combined analyses identified significant (P < 5.0 × 10(-8)) associations between NOA risk and common variants near PRMT6 (rs12097821 at 1p13.3: odds ratio (OR) = 1.25, P = 5.7 × 10(-10)), PEX10 (rs2477686 at 1p36.32: OR = 1.39, P = 5.7 × 10(-12)) and SOX5 (rs10842262 at 12p12.1: OR = 1.23, P = 2.3 × 10(-9)). These findings implicate genetic variants at 1p13.3, 1p36.32 and 12p12.1 in the etiology of NOA in Han Chinese men.  相似文献   
103.
To study the effect of cooperative advertising on the supply chain of deteriorating items, this paper establishes a Stackelberg game model for a two-echelon deteriorating items supply chain composed of one manufacturer and one retailer under a given support program with an exogenous participation rate. The manufacturer as the leader determines the wholesale price and production rate, and the retailer as the follower determines the retail price and advertising strategies. The strategies of the players under the decentralized scenario and the centralized scenario are respectively characterized. Numerical simulations and sensitivity analysis are conducted to gain some managerial insights. It is shown that the pricing, advertising and production strategies are negatively correlated to deteriorating coefficient, and both the profit and the channel efficiency decrease with deteriorating coefficient; The interaction between price, advertising investment and production rate results in a higher retail price of the centralized channel compared to that of the decentralized channel; Implementing the cooperative advertising program does improve the performance of the supply chain in some cases and the participation rate roughly at 0.5 is most preferable, but it is also possible to distort incentive and damage the channel performance when the participation rate reaches a relatively high level.  相似文献   
104.
建立支持宏观经济决策研讨厅的预测模型系统   总被引:10,自引:0,他引:10  
为了提高对宏观经济问题的研讨效率,研讨厅应为参加研讨的专家提供进行宏观经济预测的各种预测模型。然而,传统模型库结构框架建立的预测模型系统,已不能很好地满足支持宏观经济决策研讨厅的要求,本文从分析研讨厅的具体需要出发,提出了利用Agent理论和技术设计和实现适合支持宏观经济决策研讨厅的Agent预测模型系统。  相似文献   
105.
以天然橡胶为例,采用分子动力学模拟方法,研究了单轴拉伸条件下材料分子链聚合度参数p、环境温度T和加载率R对黏弹性材料力学性能的影响.结果 表明,材料应力随分子链聚合度和加载率的增加而增加,随温度的升高而降低,低温高频下材料呈现出塑性特点.在R=108 s-1,T=250 K的条件下,p=20,40时,材料应力峰值分别为...  相似文献   
106.
Considering a one-supplier and two-retailer supply chain setting in which the supplier makes contacts with retailers in sequence based on FCFS(first–come–first-service) principle, the authors investigate the marginal effect of extra-gain guilty fairness concerns of supply chain members on the contract design, supply chain's profit and profit distribution. When the supplier considers distributional fairness of loss aversion and extra-gain guilty, extra-gain guilty concern reduces the optimal wholesale and retail price, and improves supply chain performance. When the first or the second retailer considers distributional fairness and peer-induced fairness, extra-gain guilty concerns decrease the optimal wholesale and retail price but increase the profit of all supply chain members only when the level of loss aversion is large enough and the level of extra-gain guilty is less than 1/2. However, when the level of loss aversion is small and the level of extra-gain guilty is less than 1/2, extra-gain guilty has no influence on supply chain performance. The analysis reveals that the supply chain performance can be further improved by considering fairness of extra-gain guilty.  相似文献   
107.
随着经济全球化进程的加快,中国经济发展的战略重点已开始由沿海地区向中部地区转移,给山西发展带来了大好机遇。文章从山西的优势、瓶颈问题及解决对策等方面进行了阐述,必将对山西转型发展起到一定的借鉴作用。  相似文献   
108.
Well-crystalline CeO2 nanowires were prepared via a surfactant-assisted hydrothermal process. Reaction temperature and reaction time were changed for the determination of optimal synthesis parameters. The as-obtained products were characterized by X-ray diffraction (XRD), high-resolution transmission electron microscopy (HRTEM), and field emission scanning electron microscopy (FESEM). The results show that single crystal CeO2 nanowires with high yield and good uniformity can be obtained hydrothermally at 180°C for 12 h with the aid of 2.0 g surfactant (polyvinyl pyrrolidone, PVP). The role of PVP was then discussed and a possible growth mechanism was proposed. Moreover, room temperature photoluminescence (PL) spectra were obtained for these CeO2 nanowires, which are believed to be related to the abundant defects in these nanostructures.  相似文献   
109.
文章介绍并分析了新世纪大学英语系列教材之主干课程《综合教程》编写的宗旨和特色,探讨了在教学实践中如何贯彻《综合教程》的编写宗旨,彰显其特色,以取得良好的教学效果。  相似文献   
110.
Variable supply voltage-clustered voltage scaling (VS-CVS) scheme can be very effective in reducing power consumption of CMOS circuits without degrading system performance. Level converting flip-flops (LCFFs) are key elements in the CVS scheme. In this paper, a new explicit-pulsed double-edge triggered level converting flip-flop (nEP-DET-LCFF) is proposed, which employs double-edge triggering technique, dynamic structure, explicit pulse generator,conditional discharge technique and proper arrangement of stacked nMOS transistors to efficiently perform latching and level converting functions simultaneously. The proposed nEP-DET-LCFF combines merits of both conventional explicit-LCFFs and implicit-LCFFs. Simulation shows the proposed nEP-DET-LCFF has improvement of 19.2%~46% in delay, and 19.4%~52.9% in power-delay product (PDP) as compared with the published LCFFs.  相似文献   
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