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社会化服务供给对规模农户经济效益和绿色生产的影响

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长江流域资源与环境 2023年第3期32卷 653-664页

作者：曹铁毅邹伟江苏大学管理学院江苏镇江212013 南京农业大学公共管理学院江苏南京210095

促进规模农户的经济效益与绿色生产行为相统一对于我国农业高质量发展具有重要意义。基于江苏省规模农户的调研数据,采用倾向得分匹配法,从服务供给的视角检验社会化服务供给对规模农户经济效益和绿色生产的影响,并比较不同服务内容及... 详细信息

促进规模农户的经济效益与绿色生产行为相统一对于我国农业高质量发展具有重要意义。基于江苏省规模农户的调研数据,采用倾向得分匹配法,从服务供给的视角检验社会化服务供给对规模农户经济效益和绿色生产的影响,并比较不同服务内容及对不同类型农户的影响差异。结果表明:(1)服务供给对规模农户的经济效益和绿色生产均有积极影响,既可以提高家庭人均收入,增强收入稳定性,同时也可以促进对有机肥和测土配方施肥两类绿色生产技术的使用;(2)不同服务内容的影响存在差异。供给插秧服务、田间管理服务以及烘干服务均能提高经济效益,绿色生产方面,仅田间管理服务具有显著作用;(3)服务供给的影响还存在明显的组群差异。加入合作社、未受到信贷约束以及使用互联网的规模农户提供服务后,其经济效益和绿色生产情况改善更明显。因此,建议鼓励规模农户由单一土地经营型向“土地+服务”融合型转变,支持田间管理等市场短缺型服务的发展,并从组织化、信息化以及缓解融资约束等方面改善规模农户的服务供给环境。

关键词：农业社会化服务规模农户服务供给经济效益绿色生产

Role of oxides in the formation of hole defects in friction stir welded joint of 2519-T87 aluminum alloy

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Journal of Central South University 2022年第12期29卷 3836-3846页

作者： yi tie LIU Sheng-dan FANG Chen JIANG Geng-duo School of Materials Science and Engineering Central South UniversityChangsha 410083China National Key Laboratory of Science and Technology on High-strength Structural Materials(Central South University) Changsha 410083China Key Laboratory of Non-ferrous Metals Materials Science and Engineering of Ministry of Education(Central South University) Changsha 410083China School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China

The role of oxides in the formation of hole defects in friction stir welded joint of 2519-T87 aluminum alloy has been investigated by using optical microscope, scanning electron microscope, electron backscatter diffraction and electron probe microanalyzer to examine the distribution of oxides and the features of hole defects, and using ABAQUS 3D thermo-mechanical coupling finite element model based on arbitrary Lagrangian-Eulerian method to simulate the material flow behavior. Oxides exist at the edge of tunnel hole and in the micropores in the joint. Based on distribution of oxygen and material flow behavior, it is believed that the oxides on the surface of the alloy tend to flow down into the bulk along the flow direction of plastic material during friction stir welding, aggregate in the weak region of material flow at the intersection of the shoulder affected zone and the stir pin-tip affected zone, and consequently prevent the material from contacting and diffusing. Due to the insufficient material flow and therefore the small plastic deformation,the pressure is not high enough to compress the accumulated oxides, resulting in hole defects.

关键词： aluminum alloy friction stir welding arbitrary Lagrangian-Eulerian method hole defects oxides

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DNA损伤监测及修复相关酶与细胞衰老

生物化学与生物物理进展 2001年第1期28卷 37-39页

作者：罗瑛隋建丽铁轶北京放射医学研究所北京100850

衰老是细胞的重要生命现象之一 ,衰老假说之一认为细胞中残留DNA损伤的积累可加速细胞的衰老 .因此 ,细胞内DNA损伤监测及修复系统的正常运行与细胞衰老调控密切相关 ,DNA损伤监测及修复相关酶如PARP、DNA PK、ATM、p5 3等在细胞衰老中... 详细信息

衰老是细胞的重要生命现象之一 ,衰老假说之一认为细胞中残留DNA损伤的积累可加速细胞的衰老 .因此 ,细胞内DNA损伤监测及修复系统的正常运行与细胞衰老调控密切相关 ,DNA损伤监测及修复相关酶如PARP、DNA PK、ATM、p5 3等在细胞衰老中的调控作用日益受到广泛关注 .研究这些蛋白质分子间的相互作用及其在细胞衰老过程中的调控功能 ,有利于揭示DNA损伤应激、损伤修复调控与细胞衰老之间的内在联系 ,为抗衰老研究及从衰老角度治疗肿瘤提供新的思路 .

关键词：细胞衰老 DNA损伤监测 DNA损伤修复 tAnkYrAse

Normalization of plasma growth hormone alleviated malignant ventricular tachycardia in acromegaly

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Journal of Geriatric Cardiology 2018年第8期15卷 547-550页

作者： Zhi-Hao LIU Kang LI Yan-Sheng DING Jian-Xing QIU Steven Siyao Meng Mohetaboer Momin Sheng-Cong LIU tie-Ci yi Jian-Ping LI Department of Cardiology Peking University First Hospital Beo'ing China University of Rochester Medzcal Center Rochester NY Umted States Key Laboratory of Molecular Cardiovascular Sciences of Ministry of Education Health Science Center Peking University Beijing China

Acromegaly is an insidious endocrine disease character- ized by chronic elevation of growth hormone （GH） and insulin-like growth factor-1 （IGF-1）.Ell Persistent excess se- cretion of GH and IGF-1 damages both cardiac structure and function, leading to acromegalic cardiomyopathy, which is one of the most common causes of increased mortality in acromegaly and can result in an average of 10-year reduction in life expectancy.I2＇31 In patients with acromegaly, approximately 3% have been reported having a unique cardiomyopathy characterized by biventricular hypertrophy, myocardial necrosis, lymphocytic infiltration, interstitialfibrosis.

关键词： Acromegaly Growth hormone IGF-1 Ventricular tachycardia

尺寸效应对钢筋混凝土桥墩抗震性能影响的试验研究

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振动与冲击 2014年第18期33卷 126-132页

作者：李徐钟铁毅夏禾北京交通大学土木建筑工程学院北京100044

通过两个符合相似关系的钢筋混凝土桥墩水平低周往复加载试验,分析尺寸效应对桥墩抗震性能影响。依据量纲原理,分别比较试件墩顶力-位移曲线、墩底塑性区截面弯矩-曲率曲线、墩顶滑移位移分量及桥墩能量耗散能力,结果表明,两试件墩顶水... 详细信息

通过两个符合相似关系的钢筋混凝土桥墩水平低周往复加载试验,分析尺寸效应对桥墩抗震性能影响。依据量纲原理,分别比较试件墩顶力-位移曲线、墩底塑性区截面弯矩-曲率曲线、墩顶滑移位移分量及桥墩能量耗散能力,结果表明,两试件墩顶水平抗力、截面抵抗弯矩和曲率延性基本符合相似关系,无明显尺寸效应;但由于纵筋粘结滑移的三维影响,缩尺试件墩顶水平位移包含较大滑移位移分量,同比耗能偏低,尺寸效应显著。基于此,针对弯曲主导破坏桥墩,根据简化曲率分布模型和纵筋滑移模型,分别计算墩顶弯曲位移和滑移位移分量,推导给出模型试验中桥墩位移延性的建议反演公式。

关键词：钢筋混凝土桥墩拟静力试验尺寸效应纵筋滑移延性

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遗传算法在厦门市江东泵站优化调度中的应用

中国给水排水 2006年第8期22卷 74-76页

作者：铁志毅厦门水务集团有限公司福建厦门361009

针对供水泵站的优化调度决策问题的数学模型非线性和带有约束条件的特点,采用遗传算法来求解,并应用于厦门市大型原水泵站(江东泵站)的优化调度运行。

关键词：供水泵站优化调度遗传算法

Acalypha australis *** inhibits B16 melanoma cell metastasis through PI3K/AKT signaling pathway

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Integrative Medicine Discovery 2024年第2期8卷 1-6页

作者： Zhi-Zhong Wang tie-Shan yi Yu-Yang He Qin Zhou Bo Chen College of Biology and Food Engineering Huaihua UniversityHuaihua 418008China Key Laboratory of Research and Utilization of Ethnomedicinal Plant Resources of Hunan Province College of Biological and Food EngineeringHuaihua UniversityHuaihua 418008China

Background:Melanoma is a deadly skin tumor resulting from the malignant transformation of *** is highly malignant and invasive,with the highest mortality rate among skin *** australis L.(AAL),a plant with dual medicinal and culinary purposes,is commonly regarded as an edible wild vegetable in southern ***,AAL has a long history of medicinal use in China,often employed for its hemostatic,anti-diarrheal,and anti-inflammatory *** pharmacology has demonstrated that AAL possesses functions such as weight loss,antimicrobial activity,antiviral effects,and treatment for ulcerative ***,there is currently no research available regarding its effectiveness and mechanisms of action on ***:In this investigation,we used methyl thiazolyl tetrazolium assay to detect cell viability,transwell assay to detect cell migration and invasion ability,and Western blot assay to detect relevant signaling ***:The present study reveals that 2 mg/mL AAL effectively suppresses the metastasis of B16 cells,while simultaneously triggering the expression of key apoptosis-related proteins,including Bcl-2,Bax,and cleaved caspased *** investigations demonstrate that AAL exerts this inhibitory effect via the PI3K/AKT signal transduction pathway,as evidenced by the observed deficits in Ras,AKT,p-AKT,and PI3K expression ***:These findings indicated that AAL could be a valuable therapeutic option for reducing the metastatic potential of B16 melanoma cells.

关键词： Acalypha australis L melanoma PI3K/AKT pathway

大跨度预应力混凝土梁高大模架安全设计与施工

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中国安全生产科学技术 2010年第2期6卷 127-131页

作者：朱义铁平煤建工集团有限公司土建处平顶山467000

模板高支撑架与传统支撑体系不同,高支撑体系具有跨度大、荷载重、高度高的特点,因此,对模板的支顶设计与施工提出了更高的要求。在确定安全设计与施工专项方案时,首先应结合可组织的材料进行支架形式选型支撑架的设计除满足计算中的相... 详细信息

模板高支撑架与传统支撑体系不同,高支撑体系具有跨度大、荷载重、高度高的特点,因此,对模板的支顶设计与施工提出了更高的要求。在确定安全设计与施工专项方案时,首先应结合可组织的材料进行支架形式选型支撑架的设计除满足计算中的相关依据外,须重视其相关构造要求;其次,还应加强施工过程的管理,严把进场材料关,严格支撑架的检查验收,精心设计混凝土浇筑方案,以确保高支撑架体的整体稳定和安全。平顶山市行政服务综合楼预应力框架梁具有高、大、重的特点。以《建筑施工扣件式钢管脚手架安全技术规范》为依据,介绍了高大模架采用满堂扣件式钢管支撑架的设计与计算、施工方法、安全措施和应用效果,实践表明是可行的。

关键词：模板工程高大模架设计施工

A comparative study of primary coronary stenting andintravenous thrombolysis for acute myocardial infarctionusing^(99m) Tc-MIBI SPECT imaging

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Nuclear Science and Techniques 2000年第4期11卷 210-212页

作者： WANG tie, HU Da-yi, LI Tian-Chang, JIA San-Qing (Beijing Chaoyang Hospital, Affiliale of Capital University of Medial Sciences, Beijing 100020 )

The theraputic effectiveness of primary coronary stenting was evaluated and compared with that of intravenous thrombolysis for acute myocardial infarction (AMI) using99m Tc-MIBI myocardial SPECT imaging. 42 patients with AMI were undergone primary coronary stenting (stenting group, 23 patients) or intravenous thrombolysis therapy (thrombolysis group, 19 patients). 99mTc-MIBI myocardium SPECT imaging was performed before and 1 week after steming or thrombolysis therapy. The left ventricular myocardium of each patient was divided into 20 segments. The semiquantitative score of myocardial 99mTc-MIBI uptake was eXPressed with a five-point scoring system: 0 = normal; 1 = equivocal; 2 = mild defect; 3 = severe defect; 4 = absence of activity. The scores of scanning before stenting or intravenous throm-bolysis was SBS. The scores of scaning after stenting or intravenous thrombolysis was SAS. Deducting SAS from SBS was SDS. A comparison was made between the steming group and thrombolysis group: SBS was 41.3+9.8 and 39.4+7.9 (t=1.2, p <0.05); SAS was 17.8+6.4 and 27.3+6.7 (t=5.8, p <0.01); SDS was 24.5+4.2 and 12.2+2.3 (t = 7.3, P <0.01). In the 193 defect segments before stenting, 106 segments (54.9%) restored to normal after steming. In the 149 defect segments before intravenous thrombolysis, 61 segments (40.9%) restored to normal after thrombolysis therapy. Comparing between steming group and thrombolysis group in the improved rate of myocardial perfusion defect scores there was a significant difference (p <0.01). 99mTc-MIBI myocardial SPECT imaging has been proved to be an objective parameter for evaluating the therapeutic effectiveness of the stenting and the intravenous thrombolysis in the treatment of AMI. The results indicated that primary coronary stenting seems to be more effective than intravenous thrombolysis.

关键词： ^99mTc-MIBI 锝99 放射性核素标记溶栓疗法心肌疾病放射性药物心肌显像放射性核素显像诊断