检索结果-南通市图书馆

发达国家休闲体育政策环境发展特征、经验及启示

在线全文

学校读者我要写书评

暂无评论

上海体育学院学报 2021年第12期45卷 91-100页

作者：徐志军上海体育学院休闲学院上海200438

通过文献资料法等,分析发达国家各历史时期休闲体育政策环境发展的阶段,认为这是在政府引导下的一个渐进过程,经历了初步引导、大力提倡、系统化干预和引导社会资本主导等阶段。其主要经验概括为:政府投资建设大量公共体育场所和设施;... 详细信息

通过文献资料法等,分析发达国家各历史时期休闲体育政策环境发展的阶段,认为这是在政府引导下的一个渐进过程,经历了初步引导、大力提倡、系统化干预和引导社会资本主导等阶段。其主要经验概括为:政府投资建设大量公共体育场所和设施;将相当比例的彩票基金投入公共体育;重视引导社会力量和市场主导休闲体育活动;大力扶持基层非营利性体育俱乐部;重视并积极引导休闲体育与基础教育相结合;等等。基于此,提出完善我国休闲体育政策的建议:调整政府直接投资的方式、力度及方向;加大对社会资本和体育俱乐部的支持力度;调低定价,降低休闲体育参与成本;建立有效的行业信用体系和规范;初步建立政策监督和绩效评价体系等。

关键词：休闲体育体育政策政策环境发达国家公共体育

在线全文

学校读者我要写书评

暂无评论

大型储罐基础环向力计算及通用图编制

石油工程建设 1998年第1期24卷 19-25页

作者：徐至钧许朝铨恒富房地产开发有限公司北京市丰台100071 轻工部规划设计院北京100026

依据中国石化总公司行业标准SH3068-95《石油化工企业钢储罐地基与基础设计规范》，编制了不同类型储罐8个系列环墙基础的计算环向力设计选用表与环墙基础通用图，并与SHJ1058-84规范和1984年前储罐工程的环墙基础环向力计算及配筋方法... 详细信息

依据中国石化总公司行业标准SH3068-95《石油化工企业钢储罐地基与基础设计规范》，编制了不同类型储罐8个系列环墙基础的计算环向力设计选用表与环墙基础通用图，并与SHJ1058-84规范和1984年前储罐工程的环墙基础环向力计算及配筋方法进行了分析对比。

关键词：大型储罐计算环向力化工设备

Silencing of early auxin responsive genes MdGH3-2/12 reduces the resistance to Fusarium solani in apple

在线全文

学校读者我要写书评

暂无评论

Journal of Integrative Agriculture 2024年第9期23卷 3012-3024页

作者： Qianwei Liu Shuo xu Lu Jin Xi Yu Chao Yang Xiaomin Liu zhijun Zhang Yusong Liu Chao Li Fengwang Ma State Key Laboratory for Crop Stress Resistance and High-Efficiency Production/Shaanxi Key Laboratory of Apple College of HorticultureNorthwest A&F UniversityYangling 712100China

Apple replant disease(ARD)has led to severe yield and quality reduction in the apple *** solani(***)has been identified as one of the main microbial pathogens responsible for ***(indole-3-acetic acid,IAA),an endogenous hormone in plants,is involved in almost all plant growth and development processes and plays a role in plant immunity against *** Hagen3(GH3)is one of the early/primary auxin response *** aim of this study was to evaluate the function of MdGH3-2 and MdGH3-12 in the defense response of *** by treating MdGH3-2/12 RNAi plants with *** results show that under *** infection,RNAi of MdGH3-2/12 inhibited plant biomass accumulation and exacerbated root *** inoculation with ***,MdGH3-2/12 RNAi inhibited the biosynthesis of acid-amido *** led to the inhibition of free IAA combining with amino acids,resulting in excessive free IAA *** excessive free IAA altered plant tissue structure,accelerated fungal hyphal invasion,reduced the activity of antioxidant enzymes(SOD,POD and CAT),increased the reactive oxygen species(ROS)level,and reduced total chlorophyll content and photosynthetic ability,while regulating the expression of PR-related genes including PR1,PR4,PR5 and *** also changed the contents of plant hormones and amino acids,and ultimately reduced the resistance to *** conclusion,these results demonstrate that MdGH3-2 and MdGH3-12 play an important role in apple tolerance to *** and ARD.

关键词： Fusarium solani early auxin responsive gene apple replant disease plant hormone antioxidant

Induced neural stem cells regulate microglial activation through Akt-mediated upregulation of CXCR4 and Crry in a mouse model of closed head injury

在线全文

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第5期20卷 1416-1430页

作者： Mou Gao Qin Dong Dan Zou zhijun Yang Lili Guo Ruxiang xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People’s HospitalSchool of MedicineUniversity of Electronic Science and Technology of ChinaChengduSichuan ProvinceChina Department of Neurosurgery Chinese PLA General HospitalBeijingChina Department of Neurology Fu Xing HospitalCapital Medical UniversityBeijingChina

Microglial activation that occurs rapidly after closed head injury may play important and complex roles in neuroinflammation-associated neuronal damage and *** previously reported that induced neural stem cells can modulate the behavior of activated microglia via CXCL12/CXCR4 signaling,influencing their activation such that they can promote neurological ***,the mechanism of CXCR4 upregulation in induced neural stem cells remains *** this study,we found that nuclear factor-κB activation induced by closed head injury mouse serum in microglia promoted CXCL12 and tumor necrosis factor-αexpression but suppressed insulin-like growth factor-1 ***,recombinant complement receptor 2-conjugated Crry(CR2-Crry)reduced the effects of closed head injury mouse serum-induced nuclear factor-κB activation in microglia and the levels of activated microglia,CXCL12,and tumor necrosis factor-α.Additionally,we observed that,in response to stimulation(including stimulation by CXCL12 secreted by activated microglia),CXCR4 and Crry levels can be upregulated in induced neural stem cells via the interplay among CXCL12/CXCR4,Crry,and Akt signaling to modulate microglial *** agreement with these in vitro experimental results,we found that Akt activation enhanced the immunoregulatory effects of induced neural stem cell grafts on microglial activation,leading to the promotion of neurological recovery via insulin-like growth factor-1 secretion and the neuroprotective effects of induced neural stem cell grafts through CXCR4 and Crry upregulation in the injured cortices of closed head injury ***,these beneficial effects of Akt activation in induced neural stem cells were positively correlated with the therapeutic effects of induced neural stem cells on neuronal injury,cerebral edema,and neurological disorders post–closed head *** conclusion,our findings reveal that Akt activation may enhance the immunoregulatory effects of induced neura

关键词： Akt signaling cerebral edema closed head injury Crry CXCR4 induced neural stem cell microglia neuroinflammation

在线全文

学校读者我要写书评

暂无评论

PDA桩基检测技术的应用与评价

石油工程建设 1995年第2期21卷 9-14页

作者：徐至钧中外合资济南恒泉房地产开发有限公司山东省济南市250014

桩基工程动力检测是我国目前应用较广的一种桩基非破损动力检验方法。动测法（又称锤击贯入试桩法）试桩费用一般仅为静载试桩费用的1／2～1／3，而且试验和分析法简单易行，试验结果直观可靠。本文在介绍PDA桩基检测技术的检测设备、... 详细信息

桩基工程动力检测是我国目前应用较广的一种桩基非破损动力检验方法。动测法（又称锤击贯入试桩法）试桩费用一般仅为静载试桩费用的1／2～1／3，而且试验和分析法简单易行，试验结果直观可靠。本文在介绍PDA桩基检测技术的检测设备、测试方法和两种分析方法的基础上，结合工程实例和数据对该技术予以评价。

关键词：桩基础检测试桩基础高应变动力

在线全文

学校读者我要写书评

暂无评论

无粘结预应力混凝土的应用与前景

石油工程建设 1996年第5期22卷 9-15页

作者：徐志钧中外合资北京恒富房地产开发公司北京市丰台区100071

本文综述“八五”重点科技推广项目“无粘结预应力混凝土技术”的应用范例和推广前景，针对其“后张法”施工的工艺特点，结合JGJ／T92－93《无粘结预应力混凝土结构技术规程》，介绍构件的预应力计算、锚具配置、构造特点和混凝土浇筑... 详细信息

本文综述“八五”重点科技推广项目“无粘结预应力混凝土技术”的应用范例和推广前景，针对其“后张法”施工的工艺特点，结合JGJ／T92－93《无粘结预应力混凝土结构技术规程》，介绍构件的预应力计算、锚具配置、构造特点和混凝土浇筑的施工工艺，并对预应力筋的材料选用、处理和铺放以及现场浇筑施工、张拉设备的配备提供了可资借鉴的经验。

关键词：钢筋混凝土预应力受力分析钢丝

基于六轴多旋翼飞行器的赤眼蜂投放系统设计与试验

在线全文

学校读者我要写书评

暂无评论

农业机械学报 2016年第1期47卷 1-7页

作者：徐东甫白越宫勋续志军中国科学院长春光学精密机械与物理研究所长春130033 中国科学院大学北京100039

为更好地进行农作物病虫害防治,结合农业无人机和生物防治,设计了一种基于Hex-Rotor飞行器的赤眼蜂投放系统,实现赤眼蜂自主投放功能。首先,使用共轴双桨和旋翼系统的倾斜配置,对6轴多旋翼飞行器结构进行了改进,提高了系统的冗余性和可... 详细信息

为更好地进行农作物病虫害防治,结合农业无人机和生物防治,设计了一种基于Hex-Rotor飞行器的赤眼蜂投放系统,实现赤眼蜂自主投放功能。首先,使用共轴双桨和旋翼系统的倾斜配置,对6轴多旋翼飞行器结构进行了改进,提高了系统的冗余性和可靠性,整个系统满载9 kg,以10 m/s的速度可飞行超过20 min;然后,利用带有扩张状态观测器和快速微分器的反步控制算法,使系统在投放干扰和外部风扰共同作用下,能够很好地完成轨迹跟踪飞行任务。最后,设计了专用的赤眼蜂投放装置,配合GPS和Google earth地图,实现赤眼蜂自主投放功能。在实际试验中,投放系统投放速度超过9 700 m2/min,飞行投放覆盖率100%,赤眼蜂孵化率75.81%。试验证明,该系统可以稳定可靠地完成赤眼蜂的投放工作,投放效率和经济效益方面表现良好,可以实现无人机自主生物防治。

关键词：生物防治无人飞行器赤眼蜂自主投放系统