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Acute effects of human protein s administration after traumatic brain injury in mice

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Neural Regeneration Research 2020年第11期15卷 2073-2081页

作者： Xiaowei wang Jing Tong Xiaodi han Xiaoming Qi Jun Zhang Erxi Wu Jason h.huang Center for Translational Neuromedicine University of RochesterRochesterNYUSA Department of Neurosurgery 4th Affiliated Hospital of Hebei Medical UniversityShijiazhuangHebei ProvinceChina Department of Neurosurgery Tiantan HospitalBeijingChina Department of Neurosurgery Baylor Scott&White HealthTempleTXUSA Department of Neurosurgery PLA General HospitalBeijingChina College of Medicine Texas A&M Health Science CenterTempleTXUSA

Despite years of effort,no effective acute phase treatment has been discovered for traumatic brain *** impediment to successful drug development is entangled secondary injury *** we show that protein s,a natural multifunctional protein that regulates coagulation,inflammation,and apoptosis,is able to reduce the extent of multiple secondary injuries in traumatic brain injury,and therefore improve *** subjected to controlled cortical impact were treated acutely(10–15 minutes post-injury)with a single dose of either protein s(1 mg/kg)or vehicle phosphate buffered saline via intravenous *** 24 hours post-injury,compared to the non-treated group,the protein s treated group showed substantial improvement of edema and fine motor coordination,as well as mitigation of progressive tissue *** and western blot targeting caspase-3,B-cell lymphoma 2(Bcl-2)along with terminal deoxynucleotidyl transferase dUTP nick end labeling(TUNEL)assay revealed that apoptosis was suppressed in treated *** targeting CD11 b showed limited leukocyte infiltration in the protein s-treated ***,protein s treatment increased the ipsilesional expression of aquaporin-4,which may be the underlying mechanism of its function in reducing *** results indicate that immediate intravenous protein s treatment after controlled cortical impact is beneficial to traumatic brain injury *** Use Protocols(AUPs)were approved by the University Committee on Animal Resources(UCAR)of University of Rochester Medical Center(approval ***-2008-102 R)on November 12,2013.

关键词： apoptosis aquaporin-4 controlled cortical impact edema inflammation protein s TBI therapy traumatic brain injury

The eco-origins, actions and demonstration roles of Beijing Green Olympic Game

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Journal of Environmental sciences 2001年第4期13卷 514-519页

作者： wang, R.-s. Res. Cntr. Eco-Environmental sci. Chinese Academy of Sciences Beijing 100085 China

The 29th Olympic Game will be held in Beijing in 2008. It will be a green game to promote sustainable development of men, cities and regions through ecological development advocating 'man and nature be in one'. 'Eco' here means a process, a driving force, an action, a culture and a kind of vitality leading to sustainable development. It is a mechanism embodying the Olympic spirit of competition, cooperation and self-reliance. The paper explained the ecological significance, connotation and objectives of Beijing Green Olympic Game. Ten major ecological heritages of Beijing have been investigated including ecologically sound landscape, culture, transportation, physical exercise, health care, sanitation, food, family relationship, agriculture, and human ecological totality. To preserve or restore the above mentioned old tradition, a green Olympic action plan has been made out in Beijing initiated by NGOs, supported by entrepreneurs and coordinated by government agencies. Four kinds of eco-engineering have been planned for blue sky, clean water, green land and eco-city development. The demonstration role of Beijing Green Olympic Game to developing regions and countries is also discussed.

关键词： Agriculture health care sanitation sustainable development Transportation

Brain-derived neurotrophic factor signaling in the neuromuscular junction during developmental axonal competition and synapse elimination

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Neural Regeneration Research 2025年第2期20卷 394-401页

作者： Josep Tomàs Víctor Cilleros-Mañé Laia Just-Borràs Marta Balanyà-segura Aleksandra Polishchuk Laura Nadal Marta Tomàs Carolina silvera-simón Manel M.santafé Maria A.Lanuza Unitat d’histologia i Neurobiologia(UhNeurob) Facultat de Medicina i Ciències de la SalutUniversitat Rovira i VirgiliReusSpain

During the development of the nervous system,there is an overproduction of neurons and *** competition between neighboring nerve endings and synapses performing different activity levels leads to their elimination or *** have extensively studied the involvement of the brain-derived neurotrophic factor-Tropomyosin-related kinase B receptor neurotrophic retrograde pathway,at the neuromuscular junction,in the axonal development and synapse elimination process versus the synapse *** purpose of this review is to describe the neurotrophic influence on developmental synapse elimination,in relation to other molecular pathways that we and others have found to regulate this *** particular,we summarize our published results based on transmitter release analysis and axonal counts to show the different involvement of the presynaptic acetylcholine muscarinic autoreceptors,coupled to downstream serine-threonine protein kinases A and C(PKA and PKC)and voltage-gated calcium channels,at different nerve endings in developmental *** dynamic changes that occur simultaneously in several nerve terminals and synapses converge across a postsynaptic site,influence each other,and require careful studies to individualize the mechanisms of specific *** describe an activity-dependent balance(related to the extent of transmitter release)between the presynaptic muscarinic subtypes and the neurotrophin-mediated TrkB/p75NTR pathways that can influence the timing and fate of the competitive interactions between the different axon *** downstream displacement of the PKA/PKC activity ratio to lower values,both in competing nerve terminals and at postsynaptic sites,plays a relevant role in controlling the elimination of supernumerary ***,calcium entry through L-and P/Q-subtypes of voltage-gated calcium channels(both channels are present,together with the N-type channel in developing nerve terminals)contributes to red

关键词： acetylcholine release adenosine receptors axonal competition brain-derived neurotrophic factor calcium channels motor end-plate muscarinic acetylcholine receptors postnatal synapse elimination serine kinases tropomyosin-related kinase receptorB

基于压力分布的环摆式双面抛光去除均匀性研究

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光学学报 2024年第16期44卷 278-291页

作者：毛晨肖博王春阳白祎凡黄思玲王大森西安工业大学兵器科学与技术学院陕西西安710000 西安工业大学光电工程学院陕西西安710000 西安工业大学西安市主动光电成像探测技术重点实验室陕西西安710000 中国兵器科学研究院宁波分院浙江宁波315103

构建了一种基于速度和压力分布模型的材料去除量分布计算模型。建立了环摆式双面抛光的有限元模型,对5种半径的上抛光盘在不同加工压力下与元件接触面的压力分布进行分析,通过拟合得到压力分布特性模型。根据Preston方程,将压力分布模... 详细信息

构建了一种基于速度和压力分布模型的材料去除量分布计算模型。建立了环摆式双面抛光的有限元模型,对5种半径的上抛光盘在不同加工压力下与元件接触面的压力分布进行分析,通过拟合得到压力分布特性模型。根据Preston方程,将压力分布模型与速度分布模型耦合,得到材料去除量分布计算模型。通过模拟加工计算,研究加工压力和上抛光盘尺寸对去除量分布及均匀性的影响,发现去除量分布主要受上抛光盘尺寸和摆动距离的影响,去除均匀性主要受加工压力的影响。通过加工实验,对所得到的材料去除量分布计算模型的准确性进行验证,并研究了加工压力和上盘尺寸对材料去除量分布及均匀性的影响。实验结果表明,上抛光盘的直径越大,则加工压力越小,材料去除的均匀性越好。基于去除量分布预测模型,利用得到的规律指导实际加工,选取初始表面面型峰谷(PV)值为2.09λ(λ=632.8 nm)、均方根(RMs)值为0.464λ的熔石英样件,通过材料去除量预测模型得到工艺参数的最优解。加工后元件表面面型PV值降至0.85λ,RMs值降至0.137λ。所提模型将元件表面PV值降低到λ以下的时间缩短至原来的50%,实现了元件表面面型的快速收敛。

关键词：大口径平面光学元件环摆式双面抛光法压力分布特性去除均匀性材料去除量计算模型

微量合金元素对Zn-Cu-Ti合金显微组织与性能的影响

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中国有色金属学报 2024年第3期34卷 787-796页

作者：王云鹏王同波杨春秀孙燕莫永达娄花芬中铝科学技术研究院有限公司北京102209 中铝材料应用研究院有限公司北京102209

通过在Zn-Cu-Ti合金中同时添加微量Cr、Mg和Cr、Ni元素,获得了Zn-1.0Cu-0.1Ti、Zn-1.0Cu-0.1Ti-0.05Cr-0.05Mg、Zn-1.0Cu-0.1Ti-0.05Cr-0.05Ni(质量分数,%)合金,并通过熔铸、热轧和冷轧处理制备了合金板材,对合金的显微组织、力学性能、抗蠕变性能和耐腐蚀性能进行分析。结果表明:Zn-Cu-Ti合金中同时添加Cr、Mg和Cr、Ni元素后,合金力学性能、抗蠕变性能和耐腐蚀性能均明显提高。Zn-1.0Cu-0.1Ti-0.05Cr-0.05Mg合金抗拉强度达到343 MPa,伸长率达到40%,蠕变速率为1.38×10^(−9)s^(−1),腐蚀电位为−1.076 V,腐蚀电流密度为8.306×10^(−6)A/cm^(2),表现出最优的综合性能。合金的强化机制主要为固溶强化与析出弥散强化,细小弥散第二相有利于提高合金的抗蠕变性能,添加合金元素后,合金表面形成的致密钝化层和无粗大析出相提高了合金耐蚀性。同时,减少单道次冷轧变形率可抑制CuZn5相的形变诱导析出。

关键词：锌铜钛合金力学性能抗蠕变性能耐腐蚀性强化机制

Modification of streamer-to-leader transition model based on radial thermal expansion in the sphere-plane gap discharge at high altitude

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Plasma science and Technology 2024年第1期26卷 42-49页

作者：耿江海林果王平丁玉剑丁杨俞华 Department of Electric Power Engineering North China Electric Power UniversityBaoding 071003People’s Republic of China China Electric Power Research Institute Beijing 100192People’s Republic of China Xinjiang Electric Power Company Research Institute Urumchi 830000People’s Republic of China shanxi Electric Power Company Research Institute Taiyuan 030001People’s Republic of China

historically,streamer-to-leader transition studies mainly focused on the rod-plane gap and low altitude analysis,with limited attention paid to the sphere-plane gap at high altitude *** this work,sphere-plane gap discharge tests were carried out under the gap distance of 5 m at the Qinghai Ultra high Voltage(UhV)test base at an altitude of 2200 *** experiments measured the physical parameters such as the discharge current,electric field intensity and instantaneous optical *** duration of the dark period and the critical charge of streamer-toleader transition were obtained at high *** on radial thermal expansion of the streamer stem,we established a modified streamer-to-leader transition model of the sphere-plane gap discharge at high altitude,and calculated the stem temperature,stem radii and the duration of streamer-to-leader *** with the measured duration of sphere-plane electrode discharge at an altitude of 2200 m,the error rate of the modified model was 0.94%,while the classical model was 6.97%,demonstrating the effectiveness of the modified *** the comparisons and analysis,several suggestions are proposed to improve the numerical model for further quantitative investigations of the leader inception.

关键词： streamer-to-leader transition model high altitude streamer stem convective diffusion radial thermal expansion

“公转铁”政策对地方铁路货运业经济效益影响分析

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铁道运输与经济 2024年第5期46卷 141-147页

作者：王朔王杨堃杨瑞王超武剑红北京交通大学经济管理学院北京100044 中国宏观经济研究院综合运输研究所北京100038

为探究“公转铁”政策对我国铁路货运业经济效益的影响,以2018年开始推进的“公转铁”政策为准自然实验,基于19个省份40条地方铁路线的2012—2020年地方铁路数据和地方铁路线所在地区的经济发展数据,运用双重差分模型探究“公转铁”政... 详细信息

为探究“公转铁”政策对我国铁路货运业经济效益的影响,以2018年开始推进的“公转铁”政策为准自然实验,基于19个省份40条地方铁路线的2012—2020年地方铁路数据和地方铁路线所在地区的经济发展数据,运用双重差分模型探究“公转铁”政策对地方铁路货运业经济效益的影响。结果表明,“公转铁”政策短期内对地方铁路的货物周转量促进作用显著,对地方铁路货运业的经济效益有正向影响但不显著。“公转铁”政策带来的货物周转量增长会促进地方铁路运输企业的运输收入增加,但是为适应铁路货物周转量增加而进行的铁路基础设施改造、扩建及铁路运价调整会显著影响运输成本增加,导致短期内“公转铁”政策对地方铁路货运业的经济效益影响不显著。

关键词： “公转铁” 铁路货运业双重差分模型经济效益地方铁路

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激光熔凝处理对P20钢组织及性能的影响

表面技术 2024年第9期53卷 209-215页

作者：李勇缪星旭张成佳姜鹤明王坤王小瑾浙江工贸职业技术学院国家激光制造与材料技术协同创新中心浙江温州325026

目的提高P20模具钢的表面硬度和耐磨性能。方法采用激光熔凝技术对P20模具钢表面进行强化处理。通过硬度梯度检测和摩擦磨损测试,分别评价熔凝层的硬度分布特征和耐磨性能,并通过光学显微镜和扫描电子显微镜对熔凝层及磨痕形貌进行分析... 详细信息

目的提高P20模具钢的表面硬度和耐磨性能。方法采用激光熔凝技术对P20模具钢表面进行强化处理。通过硬度梯度检测和摩擦磨损测试,分别评价熔凝层的硬度分布特征和耐磨性能,并通过光学显微镜和扫描电子显微镜对熔凝层及磨痕形貌进行分析。结果使用激光输出功率为500W、光斑直径为2.5mm、聚焦透镜距离为40 mm、扫描速度为6 mm/s、搭接率为45%、氮气保护的激光熔凝工艺所得熔凝层的组织细小,无脱碳、畸变、裂纹等缺陷,熔凝处理质量高。熔凝过程中单道激光熔凝层呈半椭圆形分布,最大深度为610~620μm。熔凝处理后表面硬度提升显著,熔凝层的硬度分布与熔凝层的区域位置有关,具有较高硬度且硬度保持基本稳定的熔凝层深度约为400μm;单道激光熔凝层最高硬度可达460~480hV,重叠影响区即双熔凝区的最高硬度在540~560hV之间,即熔凝层硬度普遍较基体硬度提高了60%以上。此外,P20模具钢经过激光熔凝处理后耐磨性能提升明显,其平均摩擦因数约为0.85,熔凝处理的磨损失重较未处理的试样减少了约61%,其磨损机制主要表现为磨粒磨损和少量的黏着磨损或剥落脱离。结论激光熔凝处理能够显著提高P20模具钢的表面硬度和耐磨性能,试验采用的激光熔凝工艺可在P20钢表面获得硬度较高且稳定可靠的熔凝层深度在400μm左右,能将P20模具钢的表面硬度及耐磨性提高60%以上。

关键词： P20模具钢激光熔凝熔凝层显微硬度金相组织摩擦磨损

Representations of and translation between common fractions and decimal fractions

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Chinese science Bulletin 2013年第36期58卷 4630-4640页

作者： wang YunQi sIEGLER Robert s school of International studies Zhejiang University Department of Psychology Carnegie Mellon University Department of Psychology and Behavioral science Zhejiang University The siegler Center for Innovative Learning (sCIL) Beijing Normal University

Recent years have seen a boom in research on the magnitude representations of common fractions and decimal ***,previous studies generally only explored the magnitude representations of these two types of fractions in *** present study,using a pretest-training-posttest design,examined and compared the magnitude representations of both types of fractions,and more importantly examined their relations to fraction translation and overall mathematical *** results showed that(1)accurate magnitude representations developed more often for decimal fractions than for common fractions;(2)individual differences in fraction magnitude representations predicted individual differences in fraction translation performance above and beyond initial knowledge of fraction translation;(3)mere exposure to visual representations of fractions on number lines improved children’s mental representations of fraction magnitudes more than exposure to visual representations of fractions on circles or reading a textbook section on *** present findings suggest that,like whole numbers,both types of fractions are organized on a mental number line,which appears to provide a central conceptual structure for organizing a wide range of numerical *** implications of the findings are discussed.

关键词：分数小数陈述个体差异数学能力概念结构预测试幅度