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Micro-Pulse Lidar Measurements of Aerosol Vertical Structure over the Loess Plateau

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Atmospheric and Oceanic Science Letters 2008年第1期1卷 8-11页

作者： HUANG jian-ping HUANG Zhong-wei BI jian-Rong ZHANG Wu ZHANG Lei College of Atmospheric Sciences Lanzhou University Lanzhou 730000 China

Knowledge of the vertical distribution of aerosols in the free troposphere is important for estimating their impact on climate. In this study, direct observations of the vertical distribution of aerosols in the free troposphere are made using surface Micro-Pulse Lidar (MPL) measurements. The MPL measurements were made at the Loess Plateau (35.95°N, 104.1°E), which is near the major dust source regions of the Taklimakan and Gobi deserts. The vertical distribution of the MPL backscattering suggested that nondust aerosols floated from ground level to an altitude of approximately 9 km around the source regions. Early morning hours are characterized by a shallow aerosol layer of a few hundred meters thick. As the day progresses, strong convective eddies transport the aero- sols vertically to more than 1500 m.

关键词： lidar aerosol vertical structure Loess Plateau

Expression of Nuclear Factor-Kappa-B in Mouse Enometrium Treated with Different Levels of Estridiol or Progesterone

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Journal of Reproduction and Contraception 2005年第1期16卷 29-34页

作者： Qi ZENG jian-ping ZHOU wei ZHANG Yin-kun LIU Obestetrics and Gynecology Hospital Fudan University Shanghai 200011 China

Objective To investigate the effect of estridiol nuclear factor-kappa-B （NF-kB） expression in and progesterone at different levels on mouse endometrium Methods Ovarioectmized mice were randomly divided into 9 groups, i.e. groups of sham operation, of estridiol only, of progesterone only and of progesterone combined with estridiol. Mice in the experimental groups accepted subcutaneous injections of estridiol or progesterone at different levels for one week. Their uteri were collected to detect the expression of NF-kB by immunohistochemical assay. Results Estridiol at a daily dose of 30 μg/kg and 100 μg/kg could significantly stimulate the expression of NF-kB in mouse endometrium（P〈0.01）, but not in an obvious dose-dependent fashion （P〉0.05）. Progesterone alone could inhibit the expression of NF-kB in cytoplasma （P〈0.01）. Combination of estridiol and progesterone could increase NF-kB expression both in cytoplasma and nuclear （P〈0.01）. Conclusion Eestridiol can up-regulate the expression of NF-kB in mouse endometrium, while progesterone exhibits down-regulation effect. This finding suggests that estridiol and progesterone might modulate the endometrium receptivity by affecting NF-kB pathway.

关键词： estridiol progesterone endometrium NF-kB mouse

Coxsackievirus B3-induced apoptosis and Caspase-3

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Cell Research 2003年第3期13卷 203-209页

作者： jian ping YUAN,wei ZHAO,HONG TAO WANG,KAI Yu WU,TAO LI,XIAO KUI GUO,SHAN QING TONGDepartment of Microbiology and Parasitology,Shanghai Second Medical University,Shanghai 200025,China 1Department of Microbiology and Parasitology Shanghai Second Medical University Shanghai 200025 China 1Department of Microbiology and Parasitology Shanghai Second Medical University Shanghai 200025 China 1Department of Microbiology and Parasitology Shanghai Second Medical University Shanghai 200025 China 1Department of Microbiology and Parasitology Shanghai Second Medical University Shanghai 200025 China 1Department of Microbiology and Parasitology Shanghai Second Medical University Shanghai 200025 China 1Department of Microbiology and Parasitology Shanghai Second Medical University Shanghai 200025 China 1Department of Microbiology and Parasitology Shanghai Second Medical University Shanghai 200025 China

Cell death can be classified into two categories: apoptosis and necrosis. Apoptotic pathway can beeither caspase-dependent or caspase-independent. Caspase-independent cytopathic effect (CPE) has beendescribed. In order to evaluate the pattern of HeLa cell death induced by Coxsackievirus B3 (CVB3)and whether apoptosis involves caspase activation, we co-cultivated HeLa cells with CVB3 and detectedthe cytopathic changes, the alteration of mRNA and protein expression of caspase-3 gene plus caspase-3activity, as well as analyzing DNA fragmentation before and after caspase-3 activity inhibition. Accordingto the results, we propose that CVB3 may induce apoptosis and necrosis in HeLa cells, the latter appearingmuch earlier. Caspase-3 is activated at the levels of both transcription and translation, and procaspase-3 isproteolytically cleaved, thus leading to the continuous increasing of both caspase-3 precursor protein and itssubunit. However, besides CPE, apoptosis induced by CVB3 is not a direct consequence of

关键词： Coxsackievirus B3 (CVB3) apoptosis. caspase-3.

Apoptosis of human pancreatic cancer cells induced by Triptolide

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World Journal of Gastroenterology 2008年第10期14卷 1504-1509页

作者： Guo-Xiong Zhou Xiao-Ling Ding Jie-Fei Huang Hong Zhang Sheng-Bao Wu jian-ping Cheng Qun wei Department of Gastroenterology Affiliated Hospital of Nantong University Nantong 226001 Jiangsu Province China

AIM: To investigate apoptosis in human pancreatic cancer cells induced by Triptolide (TL), and the relationship between this apoptosis and expression of caspase-3' bcl-2 and bax. METHODS: Human pancreatic cancer cell line SW1990 was cultured in DMEM media for this study. MTT assay was used to determine the cell growth inhibitory rate in vitro. Flow cytometry and TUNEL assay were used to detect the apoptosis of human pancreatic cancer cells before and after TL treatment. RT-PCR was used to detect the expression of apoptosis-associated gene caspase-3' bcl-2 and bax. RESULTS: TL inhibited the growth of human pancreatic cancer cells in a dose-and time-dependent manner. TL induced human pancreatic cancer cells to undergo apoptosis with typically apoptotic characteristics. TUNEL assay showed that after the treatment of human pancreatic cancer cells with 40 ng/mL TL for 12 h and 24 h, the apoptotic rates of human pancreatic cancer cells increased significantly. RT-PCR demonstrated that caspase-3 and bax were significantly up-regulated in SW1990 cells treated with TL while bcl-2 mRNA was not. CONCLUSION: TL is able to induce the apoptosis in human pancreatic cancer cells. This apoptosis may be mediated by up-regulating the expression of apoptosis- associated caspase-3 and bax gene.

关键词： Triptolide Pancreatic cancer Apoptosis Bcl-2 Caspase-3 Bax

Pancreatic encephalopathy in 24 patients with severe acute pancreatitis

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Hepatobiliary & Pancreatic Diseases International 2004年第4期3卷 608-611页

作者： Xiong Ding, Chang-An Liu, jian-ping Gong and Sheng-wei Li Chongqing, China Department of Hepatobiliary Surgery, Second Clinical College, Chongqing University of Medical Sciences, Chongqing 400010, China Department of Hepatobiliary Surgery Second Clinical College Chongqing University of Medical Sciences Chongqing 400010 China. dingpanda@***

BACKGROUND: Pancreatic encephalopathy (PE), an un- familiar complication of severe acute pancreatitis ( SAP) , is difficult to diagnose and treat, and it has a high mortality. The aim of this study was to investigate the manifestation, classification, mechanism and therapy of PE. METHODS: Of 132 patients with SAP treated at our hospi- tal from March 1994 to March 2004, 24 patients complicated by PE were analyzed retrospectively. RESULTS: The causes of SAP were mostly biliary and alco- holic. Twenty-four patients (18.2%) were complicated by PE within 3 hours-38 days ( average 6. 6 days) [ 21 (87. 5%) within 2 weeks, and 3(12.5%) after 2 weeks]. Eleven pa- tients were male and 13 female, with an average of 47 years (range 25-72 years). Excitement or restrain was the main manifestation. Nine patients (37.5%) received surgery and 15 (62.5%) conservative treatment, with a mortality of 11.1 % (1/9) and 66.7% (10/15), respectively. CONCLUSIONS: PE occurs 2 weeks after SAP and is part of multiple organ failure (MOF). Some patients have PE in the late stage of SAP because of lack of VitB1 and nutri- tion. But PE can be prevented by prescribing adequate nu- trition and VitB1 in the early stage of SAP.

关键词： pancreatitis acute illness brain illness

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航天器多脉冲悬停控制的非线性方法

宇航学报 2016年第12期37卷 1466-1472页

作者：程博袁建平马卫华西北工业大学航天学院西安710072 北京宇航系统工程研究所北京100076 航天飞行动力学技术重点实验室西安710072

为解决连续推力空间悬停控制技术对航天器控制推进系统要求较高、工程上难于实现的问题,提出基于Clohessy-Wiltshire方程的多脉冲悬停控制方法。以轨道要素外推的飞行状态非线性预测方法和脉冲悬停控制量优化算法,对悬停脉冲进行了优化... 详细信息

为解决连续推力空间悬停控制技术对航天器控制推进系统要求较高、工程上难于实现的问题,提出基于Clohessy-Wiltshire方程的多脉冲悬停控制方法。以轨道要素外推的飞行状态非线性预测方法和脉冲悬停控制量优化算法,对悬停脉冲进行了优化,可以实现主动航天器在目标航天器附近任意点的近似稳定悬停。给出的多脉冲悬停控制方法及控制量非线性优化算法考虑了地球非球形引力摄动J2项影响,补偿了Clohessy-Wiltshire方程的线性化误差,能有效提高悬停精度。仿真结果表明,多脉冲悬停控制方法的燃料消耗与连续推力悬停方法相比没有明显增加,不会对主动航天器带来过大的燃料消耗压力。

关键词：航天器悬停速度脉冲非线性控制量优化

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两代农民工职业流动的影响因素及差异分析

软科学 2017年第2期31卷 38-43页

作者：柳建平魏雷西北师范大学商学院兰州730070

利用对甘肃10个村庄外出务工农民工的调查资料,基于代际差异视角,在统计分析其特征差异的基础上,通过泊松回归模型分别对两代农民工职业流动的影响因素进行了计量分析,并进一步运用Oaxaca-Blinder分解方法,分离出造成两代农民工职业流... 详细信息

利用对甘肃10个村庄外出务工农民工的调查资料,基于代际差异视角,在统计分析其特征差异的基础上,通过泊松回归模型分别对两代农民工职业流动的影响因素进行了计量分析,并进一步运用Oaxaca-Blinder分解方法,分离出造成两代农民工职业流动频次差异的主要原因。研究表明:两代农民工存在明显的特征差异,且各种因素对职业流动的影响结果也呈现出较大的差异。个体特征差异是导致两代农民工职业流动频次差异的主要原因,家庭储蓄率低、未婚比例高、家庭劳动力多等因素提高了新生代农民工的职业流动性,提高受教育水平、拓宽就业分布有利于两代农民工的就业稳定。

关键词：农民工代际差异职业流动影响因素

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自适应滤波在光电技术提取心率方法中的应用

激光与红外 2017年第1期47卷 72-76页

作者：唐宇欧建平王威长沙理工大学计算机与通信工程学院湖南长沙410114 长沙理工大学综合交通运输大数据智能处理湖南省重点实验室湖南长沙410114 国防科技大学电子科学与工程学院湖南长沙410073

针对利用光电容积脉搏波提取心率时,传统方法光电检测电路复杂,容易受运动干扰等缺陷,设计了一种实时高效的心率提取方案。采用发光二极管产生的单束波长为940 nm的红外光,利用光电容积脉搏波原理,采集手腕处PPG信号,实现对心率信号的... 详细信息

针对利用光电容积脉搏波提取心率时,传统方法光电检测电路复杂,容易受运动干扰等缺陷,设计了一种实时高效的心率提取方案。采用发光二极管产生的单束波长为940 nm的红外光,利用光电容积脉搏波原理,采集手腕处PPG信号,实现对心率信号的实时监测;并针对运动干扰提出一种自适应滤波方法,利用三轴加速度计获取噪声信号消除运动伪差。实验表明,设计与医用监测仪有良好的一致性,且提出的自适应算法比传统快速傅里叶方法具有更高的准确性,在穿戴设备允许的误差范围内,可以利用本文设计进行无创实时的心率监测。

关键词：光电容积脉搏波红外光心率加速度信号自适应滤波

Acute and chronic excitotoxicity in ischemic stroke and late-onset Alzheimer's disease

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Neural Regeneration Research 2025年第7期20卷 1981-1988页

作者： Shan ping Yu Emily Choi Michael Qjiang Ling wei Department of Anesthesiology Emory University School of MedicineAtlantaGAUSA Center for Visual and Neurocognitive Rehabilitation Atlanta Veterans Affairs Medical CenterDecaturGAUSA

Stroke and Alzheimer's disease are common neurological disorders and often occur in the same *** comorbidity of the two neurological disorders represents a grave health threat to older *** review presents a brief background of the development of novel concepts and their clinical *** activity of glutamatergic N-methyl-D-aspartate receptors and N-methyl-D-aspartate receptor-mediated Ca^(2+)influx is critical for neuronal *** ischemic insult induces prompt and excessive glutamate release and drastic increases of intracellular Ca^(2+)mainly via N-methyl-D-aspartate receptors,particularly of those at the extrasynaptic *** Ca^(2+)-evoked neuronal cell death in the ischemic core is dominated by necrosis within a few hours and days known as acute ***,mild but sustained Ca^(2+)increases under neurodegenerative conditions such as in the distant penumbra of the ischemic brain and early stages of Alzheimer's disease are not immediately toxic,but gradually set off deteriorating Ca^(2+)-dependent signals and neuronal cell loss mostly because of activation of programmed cell death *** on the Ca^(2+)hypothesis of Alzheimer's disease and recent advances,this Ca^(2+)-activated“silent”degenerative excitotoxicity evolves from years to decades and is recognized as a unique slow and chronic *** N-methyl-D-aspartate receptor subunit GluN3A,primarily at the extrasynaptic site,serves as a gatekeeper for the N-methyl-D-aspartate receptor activity and is neuroprotective against both acute and chronic *** stroke and Alzheimer's disease,therefore,share an N-methyl-D-aspartate receptor-and Ca^(2+)-mediated mechanism,although with much different time *** is thus proposed that early interventions to control Ca^(2+)homeostasis at the preclinical stage are pivotal for individuals who are susceptible to sporadic late-onset Alzheimer's disease and Alzheimer's disease-related

关键词： Ca^(2+)hypothesis cognitive deficits hyperactivity late-onset Alzheimer's disease neurodegeneration N-methyl-D-aspartate receptors N-methyl-D-aspartate receptor subunits pathogenesis preventive treatment