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Two Innovative Techniques to Study the Environmental Impacts of Urban Forms

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Two Innovative Techniques to Study the Environmental Impacts...

Low dose of corticosterone treatment with exercise increases hippocampal cell proliferation, and improves cognition

第四届粤港澳可持续发展研讨会

作者： U wa tang Department of Civil and Environmental Engineering University of Macau

This paper introduces two innovative techniques,i.e.,the vehicle-following measuring technique and the high-spatial resolution air/noise modeling technique,that have been used recently to study of urban environment in the Macao *** related interna- tional conference papers have been awarded as one of the best student papers in the annual din- ner of the Hong Kong Society for Transportation Studies in 2007 and the annual dinner of the International Association of Chinese Professionals in Geographic Information Sciences in 2008. By using the vehicle-following measuring technique,vehicle gaseous emissions(NO, CO,CO and HC)and driver’s particle exposures(PM1,PM2.5,and PM10)have been measured during heavy traffic congestion in urban *** with the traditional la- boratory tests,the vehicle-following measurement technique can obtain a wide variety of vehi- cle emission data on the road as cooperation from the vehicle’s owners is no longer necessary. By using the high-spatial resolution modeling technique,traffic-induced air and noise pollu- tions in front of individual building facades on both sides of the road can be *** two innovative techniques have the capability to provide city decision-makers with a different perspective on vehicle transport and urban form that both impact air quality and noise.

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Neural Regeneration Research 2011年第34期6卷 2645-2655页

作者： Suk-Yu Yau Jada Chia-Di Lee Benson Wui-Man Lau Tatia M.C. Lee Yick-Pang Ching Siu-wa tang Kwok-Fai So Department of Anatomy LKS Faculty of Medicine the University of Hong Kong State Key Laboratory of Brain and Cognitive Science LKS Faculty of Medicine the University of Hong Kong Research Centre of Heart Brain Hormone and Health Aging LKS Faculty of Medicine the University of Hong Kong Laboratory of Neuropsychology the University of Hong Kong Laboratory of Cognitive Affective Neuroscience the University of Hong Kong Joint Laboratory for Brain Function and Health (BFAH) Jinan University and the University of Hong Kong

Intermediate level of stress is beneficial for brain functions, whereas extreme low level or high level of stress is deleterious. We have previously shown that chronic exposure to high doses of corticosterone （CORT） suppressed hippocampal plasticity and physical exercise in terms of running counteracted the detrimental effects of CORT treatment. We aimed to study whether a mild stress, that mimicked by a treatment with low CORT dose, improved hippocampal plasticity in terms of hippocampal cell proliferation and dendritic remodeling, and to examine whether running with CORT treatment showed an additive effect on improving hippocampal plasticity. The rats were treated with 20 mg/kg CORT for 14 days with or without running, followed by Morris water maze test or forced swim test. The hippocampal proliferating cells was labeled by intraperitoneal injection of 5-bromo-2＇-deoxyuridine. The dendritic morphology was analyzed using Golgi staining method. Treatment with 20 mg/kg CORT alone yielded a higher number of hippocampal cell proliferation and significantly increased dendritic branching compared to vehicle-treated non-runners, but had no behavioral effects. In contrast, CORT treatment with running showed an additive increase in hippocampal cell proliferation and dendritic remodeling that was associated with improved spatial learning and decreased depression-like behavior; however, there was no additive improvement in behavior compared to vehicle-treated runners. These findings suggest that mild stress does not always cause detrimental effect on the brain, and combining mild stress with running could promote hippocampal plasticity via inducing cell proliferation and dendritic remodeling.

关键词： hippocampal cell proliferation physical exercise spatial learning stress structural plasticity neural plasticity

Challenges and strategies in high-accuracy manufacturing of the world’s largest SiC aspheric mirror

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Light(Science & Applications) 2022年第12期11卷 2873-2885页

作者： Xuejun Zhang Haixiang Hu Xiaokun wang Xiao Luo Ge Zhang Wenxing Zhao Xiaoyi wang Zhenyu Liu Ling Xiong Erhui Qi Congcong Cui Yanchao wang Yingjie Li Xu wang Longxiang Li Yang Bai Qiang Cheng Zhiyu Zhang Ruigang Li wa tang Xuefeng Zeng Weijie Deng Feng Zhang Changchun Institute of Optics Fine Mechanics and PhysicsChinese Academy of Sciences130033 ChangchunJilinChina University of Chinese Academy of Sciences 100049 BeijingChina

In the process of manufacturing the world’s largest silicon carbide(SiC)aspheric mirror,the primary difficulties are mirror blank preparation,asphere fabrication,and testing,as well as cladding and ***,the challenges include the homogeneity of the complicated structure casting,accuracy and efficiency of the fabrication process,print-through effect,fidelity and precision of test procedure,stress and denseness of cladding process,the dynamic range of interferometric measurement,and air turbulence error due to the long optical *** break through such a barrier of difficulties,we proposed the water-soluble room temperature vanishing mold and gel casting technology,homogeneous microstructure reaction-formed joint technology,nano-accuracy efficient compound fabrication,gravity unloading technology,high-denseness low-defect physical vapor deposition(PVD)Si-cladding technology,test data fusion method,and time-domain averaging method,*** on the proposed technologies and methods,we have accomplished the world’s largest SiC aspheric mirror with a size of φ4.03 *** impressive performance of the SiC aspheric mirror is validated by the characteristics of the fabricated SiC aspheric *** aerial density of the SiC blank is less than 120 kg/m^(2),surface shape test accuracy is better than 6 nm RMS,thickness inhomogeneity of the cladding layer is less than 5%,and the final surface figure error and roughness are 15.2 nm RMS and 0.8 nm RMS,respectively.

关键词： cladding casting carbide

Corticosterone suppresses dendritic maturation of immature neurons in hippocampus,which is counteracted by antidepressant treatment

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Corticosterone suppresses dendritic maturation of immature n...

中国神经科学学会第四次会员代表大会暨第八届全国学术会议

作者： Benson WM LAU Suk-Yu YAU Tatia M.C.LEE Yick-Pang CHING Siu-wa tang Kwok-Fai SO Department of Anatomy Li Ka Shing Faculty of MedicineThe University of Hong Kong The State Key Laboratory of Brain and Cognitive Sciences The University of Hong Kong Research Centre of Heart BrainHormone and Healthy AgingFaculty of MedicineThe University of Hong Kong The State Key Laboratory of Brain and Cognitive Sciences The University of Hong KongPokfulam Laboratory of Neuropsychology The University of Hong Kong Department of Anatomy Li Ka Shing Faculty of MedicineThe University of Hong KongPokfulam Joint Laboratory for Brain function and Health(BFAH) Jinan University and The University of Hong Kong

＜正＞Objective Chronic corticosterone treatment was shown to suppress neurogenesis in hippocampus,while antidepressant treatment increases new hippocampal neuron *** previously showed that the suppressed neurogenesis in hippocampus could be attenuated by simultaneous selective serotonin reuptake inhibitor（SSRI） treatment. However,it is unknown whether the dendritic maturation of immature neurons is affected by these two classes of drugs. Method Sprague-Dawley rats were divided into four groups:（1）.corticosterone treatment,（2）.Paroxetine（a SSRI） treatment,（3）.co-treatment of corticosterone and paroxetine and（4）.control group with vehicle *** two weeks’ treatment,animals were killed and brain sections were immunostained with anti-doublecortin（DCX,an immature neuron marker） *** morphologies of immature neurons were analyzed by Sholl *** tissue was collected for brain-derived neurotrophic factor ELISA assay and DCX *** Compared to control group, immature neurons of corticosterone group showed a decreased dendritic *** contrast,paroxetine treatment increased the dendritic ***-treatment group showed dendritic complexity which is similar to control group. Hippocampal BDNF level is significantly decreased in corticosterone treatment group while co-treatment with paroxetine reversed the *** treatment also increased the expression level of DCX in *** Apart from neurogenesis,the present study shows that corticosterone and SSRI also affect dendritic growth of immature *** effect is associated with alternated hippocampal BDNF and DCX expression *** finding provides a new perspective on how stress hormone and antidepressant affect neuroplasticity,which may underlie the pathology of depressive and other psychiatric disorders.

关键词： corticosterone stress SSRI selective serotonin reuptake inhibitors neurogenesis doublecortin DCX hippocampus

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离子束抛光去除函数计算与抛光实验

光学精密工程 2015年第1期23卷 31-39页

作者：唐瓦邓伟杰郑立功张学军中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

由于传统的离子抛光工艺采用的确定去除函数的方法操作复杂且成本很高,本文提出了利用法拉第杯对离子束流空间分布进行测量、标定的方法,并计算得到不同离子源工作参数对应的去除函数。首先,基于离子束抛光材料去除原理,研究了离子束抛... 详细信息

由于传统的离子抛光工艺采用的确定去除函数的方法操作复杂且成本很高,本文提出了利用法拉第杯对离子束流空间分布进行测量、标定的方法,并计算得到不同离子源工作参数对应的去除函数。首先,基于离子束抛光材料去除原理,研究了离子束抛光过程中束流分布与能量对去除函数的影响,并提出简化的离子束抛光去除函数模型。然后,设计实验并得出离子束流空间分布与去除函数相关参数间的关系,计算得到了不同离子源工作参数产生的离子束流对应的去除函数。对硅和融石英玻璃的相关实验表明:利用法拉第杯扫描结果计算相同材料的去除函数的单位时间体积去除率与实际测量值误差小于2%。结合抛光实验,对Φ800mm碳化硅表面硅改性层平面镜进行抛光,得到的初始面形误差均方根(RMS)值为57.886nm,两次抛光后RMS值为11.837nm,收敛率达到4.89,满足精密光学加工对去除函数的确定性及精度的要求,并大大提升了确定去除函数的效率。

关键词：光学加工离子束抛光溅射效应法拉第杯扫描去除函数

VABE550型轮斗挖掘机在布沼坝露天矿的应用

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露天采矿技术 2008年第3期23卷 6-8,12页

作者：王堂娃云南省小龙潭矿务局布沼坝露天矿云南开远661601

介绍了布沼坝露天煤矿采用轮斗挖掘机连续工艺的技术参数、工艺系统布置、适用条件、特点及开采程序等内容,希望对露天矿应用轮斗挖掘机连续工艺提供借鉴。

关键词：轮斗挖掘机露天矿应用

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离子束抛光高陡度离轴非球面的去除函数修正

光学精密工程 2015年第6期23卷 1572-1579页

作者：唐瓦邓伟杰李锐钢郑立功张学军中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

研究了三轴离子束系统抛光大口径高陡度离轴非球面过程中镜面曲率变化对离子束抛光去除函数的影响。提出了利用修正矩阵修正各驻留点处的去除函数信息,进而实现对高陡度离轴非球面高精度抛光的方法。该方法通过对离轴非球面进行坐标转... 详细信息

研究了三轴离子束系统抛光大口径高陡度离轴非球面过程中镜面曲率变化对离子束抛光去除函数的影响。提出了利用修正矩阵修正各驻留点处的去除函数信息,进而实现对高陡度离轴非球面高精度抛光的方法。该方法通过对离轴非球面进行坐标转换来降低陡度变化对去除函数的影响;基于Sigmund溅射理论分析离子束抛光非球面材料的去除率,建立离子束抛光非球面去除函数模型,计算了材料去除率在非球面各驻留点处的变化。最后,根据投影原理计算在各驻留点处去除函数的半宽,得到以驻留点矩阵为基础的去除函数修正矩阵,从而掌握每一个驻留点处的去除函数信息,然后根据计算机控制光学表面成形(CCOS)原理解得加工驻留时间分布。选取口径为900mm×680mm,离轴量为350mm的离轴体育场型非球面镜进行了抛光实验,实验显示抛光后非球面镜面形精度的RMS值由32.041nm达到11.566nm,收敛率达2.77,对实际加工具有指导意义。

关键词：光学制造离轴非球面离子束抛光溅射效应去除函数

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高能量大束流氩离子枪的研发

核技术 2021年第9期44卷 39-44页

作者：朱美强石晓倩唐瓦邓伟杰郭方准大连交通大学大连116028 中国科学院长春光学精密机械与物理研究所长春130033

为了实现对大口径碳化硅非球面反射镜的表面改性层硅的高精度快速抛光,设计制作了高能量大束流氩离子枪。通过热灯丝和阳极栅网的组合实现氩原子的离子化,通过调节氩离子所处区域的电位来确定离子的能量,通过静电聚焦透镜来实现氩离子... 详细信息

为了实现对大口径碳化硅非球面反射镜的表面改性层硅的高精度快速抛光,设计制作了高能量大束流氩离子枪。通过热灯丝和阳极栅网的组合实现氩原子的离子化,通过调节氩离子所处区域的电位来确定离子的能量,通过静电聚焦透镜来实现氩离子的聚焦。调节灯丝和阳极栅网之间的电压达到离子化率的最大化,调节静电聚焦透镜的尺寸和相对位置实现氩离子的高透过率。氩离子枪的材料选择既需满足超高真空使用又要避免产生真空放电。通过理论计算和模拟氩离子束流的轨迹,确定了氩离子枪各主要组件的参数。测试结果表明:氩离子的加速电压可达20 kV,在工作距离为30 mm和氩气分压为1.2×10^(−2) Pa的情况下,可产生50μA的氩离子束流,束斑的直径在19~24 mm之间连续可调。该氩离子枪体积小,可以安装在真空多维位移台上进行大范围的运动,实现对大口径光学元件的高真空表面抛光。

关键词：氩离子枪光学镜面抛光表面科学静电透镜

子孔径拼接和计算全息混合补偿检测大口径凸非球面(特邀)

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红外与激光工程 2022年第9期51卷 67-75页

作者：苏航王孝坤程强李凌众王晶李雯研吴琼唐瓦罗霄张学军中国科学院长春光学精密机械与物理研究所吉林长春130033 中国科学院大学北京100049

为了实现大口径凸非球面的高精度检测,提出了将子孔径拼接检测法和计算全息补偿检测法相结合的检测方法。由于其中心的非球面度较小,采用球面波直接检测;而外圈的非球面度较大,采用子孔径拼接和计算全息混合补偿的方法进行测量,再通过... 详细信息

为了实现大口径凸非球面的高精度检测,提出了将子孔径拼接检测法和计算全息补偿检测法相结合的检测方法。由于其中心的非球面度较小,采用球面波直接检测;而外圈的非球面度较大,采用子孔径拼接和计算全息混合补偿的方法进行测量,再通过拼接算法将中心检测数据和外圈检测数据进行拼接从而得到全口径面形。结合实例对一块口径为540 mm的大口径凸非球面进行测量,并将检测结果与Luphoscan检测结果进行对比,两种方法检测面形残差的RMS值为0.019λ,自检验子孔径与拼接结果点对点相减后的RMS值为0.017λ。结果表明该方法能够实现大口径凸非球面的高精度检测。

关键词：光学检测大口径凸非球面混合补偿子孔径拼接检测计算全息