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Effect of leaf removal on photosynthetically active radiation distribution in maize canopy and stalk strength

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Journal of Integrative Agriculture 2017年第1期16卷 85-96页

作者： XUE Jun GOU Ling shi zhi-guo ZHAO Ying-shan ZHANG Wang-feng Key Laboratory of Oasis Eco-Agriculture Xinjiang Production and Construction Group/Agricultural College Shihezi University Shihezi 832000 P.R. China

The objectives of this study were to determine how the distribution of photosynthetically active radiation （PAR） in a maize canopy affected basal internode strength and stalk lodging. The distributions of PAR within the canopies of two maize cultivars （Zhongdan 909 and Xinyu 41） were altered by removing whole leaves or half leaves in different canopy layers. The results showed that removing whole leaves or half leaves above the three-ear-leaves （RAE and RAE/2） at flowering sig- nificantly increased. PAR at the ear and interception of PAR （IPAR） from the ear to middle of the ear and soil surface. These changes increased the structural carbohydrate content and rind penetration strength （RPS） of the third basal internode by 5.4-11.6% and reduced lodging by 4.2-7.8%. Removal of the first three leaves below the three-ear-leaves （RBE） before flowering significantly reduced IPAR from the ear to half way below the ear. This reduced the structural carbohydrate con- tent and the RPS of the third basal internode by 9.1-17.4% and increased lodging by 7.0-11.2%. Removal of the three lowest green leaves （RB） in the canopy before flowering increased PAR at the bottom of the canopy, but had no effect on the structural carbohydrate content of the basal internode, the RPS, and the lodging rate. Overall, the results indicated that the key factors affecting the basal internode strength formation and lodging were PAR at the ear and IPAR from the ear to halfway below the ear. Increasing PAR at the ear and IPAR from the ear to halfway below the ear could enhance lodging resistance by increasing the structural carbohydrate content and mechanical strength of the basal internode.

关键词： maize leaf removal light distribution stalk strength lodging resistance

Effect of heme oxygenase-1 on renal function in rats with liver cirrhosis

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World Journal of Gastroenterology 2011年第3期17卷 322-328页

作者： shi-Bin guo zhi-Jun Duan Qing Li Xiao-Yu Sun Department of Gastroenterology the First Affiliated Hospital of Dalian Medical University Dalian 116001 Liaoning Province China

AIM: To investigate the role of heme oxygenase-1 (HO-1) in pathogenesis of experimental hepatorenal syndrome (HRS). METHODS: Rats were divided into liver cirrhotic group, zinc protoporphyrin IX (ZnPP) treatment group, cobalt protoporphyrin (CoPP) treatment group and sham group. Biliary cirrhosis was established by bile duct ligation in the first three groups. Rats in the ZnPP and CoPP treatment groups received intraperitoneal injection of ZnPP and CoPP, respectively, 24 h before sample collection. Expression of HO-1 mRNA in kidney was detected by reverse-transcription polymerase chain reaction, while protein expression was determined by immunohis-tochemical analysis. Hematoxylin and eosin staining was performed to observe liver cirrhosis and renal structure. Renal artery blood flow, mean arterial pressure and portal vein pressure, 24 h total urinary volume, serum and urine sodium concentrations, and creatinine clearance rate (Ccr) were also ***: The HO-1 mRNA and protein expression levels in kidney, 24 h total urinary volume, renal artery blood flow, serum and urine sodium concentration and Ccr were lower in cirrhotic group than in sham group (P < 0.05). However, they were significantly lower in ZnPP treatment group than in cirrhotic group and significantly higher in CoPP treatment group than in cirrhotic group (P < 0.05). CONCLUSION: Low HO-1 expression level in kidney is an important factor for experimental HRS.

关键词： Heme oxygenase-1 Carbon monoxide Hepatorenal syndrome Zinc protoporphyrin IX Cobalt protoporphyrin Bile duct ligation Biliary cirrhosis

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国外鱼雷电池应用进展

电源技术 2012年第11期36卷 1762-1764页

作者：石治国海军驻天津地区兵器设备军代表室天津300384

针对国外鱼雷电池的应用进展情况进行了介绍,包括应用广泛的锌银电池、镁/氧化银海水电池,先进的铝/氧化银电池和锂电池等,认为具有高比能量、高比功率的电池才能作为鱼雷电源。

关键词：锌银电池铝氧化银电池锂电池

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军用无人机电源技术进展

电源技术 2012年第5期36卷 762-763页

作者：石治国海军驻天津地区兵器设备军代表室天津300381

军用无人机在续航方面的需求不断增加,而动力紧缺会限制其执行某些特殊的任务。为了解决这个问题,科学家正致力于克服现有电池的局限性。目前比较成熟的无人机电池技术主要有燃料电池、太阳电池和锂离子电池等。综述了以上电池技术及其... 详细信息

军用无人机在续航方面的需求不断增加,而动力紧缺会限制其执行某些特殊的任务。为了解决这个问题,科学家正致力于克服现有电池的局限性。目前比较成熟的无人机电池技术主要有燃料电池、太阳电池和锂离子电池等。综述了以上电池技术及其混合技术的进展,并对其未来发展方向进行了展望。

关键词：无人机燃料电池锂离子电池太阳电池

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基于时间窗反馈机制的动态P2P信任模型

通信学报 2010年第2期31卷 120-129页

作者：石志国刘冀伟王志良北京科技大学信息工程学院北京100083

现有的信任模型在识别不诚实反馈、惩罚恶意节点的策略性动态改变行为和激励机制等方面存在不足。为了解决这些问题,提出了一个基于时间窗的局部信任模型TW-Trust,统一考虑了信任、信誉与激励三者的内在关系,同时考虑了时间因素对信任... 详细信息

现有的信任模型在识别不诚实反馈、惩罚恶意节点的策略性动态改变行为和激励机制等方面存在不足。为了解决这些问题,提出了一个基于时间窗的局部信任模型TW-Trust,统一考虑了信任、信誉与激励三者的内在关系,同时考虑了时间因素对信任计算的影响。使用直接信任、历史信誉、差别信誉、滥用信誉、相似度和激励效用6个参数来计算网络节点信任度,并通过反馈控制机制动态调节这些参数,提高了信任模型的动态适应能力。仿真实验结果表明,TW-Trust较已有模型能更好地处理恶意节点策略性动态变化行为和不诚实反馈对系统的攻击,能更好解决相似度计算中的稀疏性问题,在信任计算误差和事务失败率等性能指标上有较大提高。

关键词：信息安全信任模型对等网络信任相似度