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养殖海湾淤泥质海岸沉积物微塑料污染特征

环境科学 2024年第5期45卷 3078-3087页

作者：宋可心贺金成李昌文解思琦刘宝堃黄伟冯志华江苏海洋大学江苏省海洋生物资源与环境重点实验室江苏海洋大学江苏省海洋生物产业技术联合创新中心江苏海洋大学自然资源部滨海盐沼湿地生态与资源重点实验室自然资源部第二海洋研究所海洋生态系统与生物地球化学重点实验室

微塑料污染是当前环境领域广泛关注的前沿问题,海洋环境介质微塑料污染广为报道,但深层沉积物中微塑料污染特征如何却鲜见报道.基于此,在典型养殖海域海州湾附近淤泥质海岸设置3个采样点,分析沉积物柱状样中微塑料污染特征.结果表明,该... 详细信息

微塑料污染是当前环境领域广泛关注的前沿问题,海洋环境介质微塑料污染广为报道,但深层沉积物中微塑料污染特征如何却鲜见报道.基于此,在典型养殖海域海州湾附近淤泥质海岸设置3个采样点,分析沉积物柱状样中微塑料污染特征.结果表明,该研究区域沉积物中微塑料丰度为(0.12±0.07)n·g^(-1),处于中等污染水平.沉积物柱状样中微塑料总和是表层5 cm沉积物中微塑料丰度的3.43~6.00倍.沉积物柱状样中微塑料丰度展现区域差异性,不同深度的沉积物中微塑料丰度不存在显著性差异,但随深度增加呈指数减少.沉积物含水率、深度和微塑料之间的关系表明,沉积物中微塑料丰度与沉积物物理性质有关.透明和黑色微塑料在各站位占比均最高,纤维是沉积物中最常见的微塑料形态,粒径小的微塑料占主体,微塑料材质的密度均不妨碍其出现在沉积物中.微塑料污染特征在不同深度沉积物中变化较大.

关键词：微塑料(MPs) 沉积物柱状样淤泥质海岸海州湾养殖海湾

基于光频域反射差分相位解调的分布式折射率传感

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光学学报 2024年第8期44卷 9-18页

作者：花培栋丁振扬刘琨郭浩晗张腾李胜刘骥江俊峰刘铁根天津大学精密仪器与光电子工程学院光电信息技术教育部重点实验室天津市光纤传感工程中心天津300072

提出一种基于光频域反射(OFDR)差分相位解调的拉锥光纤分布式折射率传感方法。首先,理论分析了差分相位解调方法的原理并仿真计算了相位随外界折射率变化的灵敏度特性。实验中利用平均去噪与小波平滑实现了340μm传感空间分辨率的分布... 详细信息

提出一种基于光频域反射(OFDR)差分相位解调的拉锥光纤分布式折射率传感方法。首先,理论分析了差分相位解调方法的原理并仿真计算了相位随外界折射率变化的灵敏度特性。实验中利用平均去噪与小波平滑实现了340μm传感空间分辨率的分布式折射率传感解调,其中有效传感区域的长度为45 mm,相位与外界折射率变化的线性拟合度为0.997,各折射率下的最大标准差为0.0067 rad,灵敏度为1328.6 rad/RIU,接近仿真结果 1483.7 rad/RIU。与互相关解调方法相比,差分相位解调方法的线性拟合度与标准差均较优,且传感空间分辨率提升了10倍。这种基于差分相位的解调方式为实现微米级分布式生物传感提供了思路。

关键词：光纤光学分布式光纤传感折射率传感光频域反射技术差分相位解调拉锥光纤

Nimodipine alleviates apoptosis-mediated impairments through the mitochondrial pathway after spinal cord injury

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Current Zoology 2011年第3期57卷 340-349页

作者： Yafei CAI Rui FAN Tianmiao hua Huiling liU Jing li College of life Sciences Anhui Normal University Key Laboratory of Biotic Environment and Ecological Safety in Anhui Province Wuhu 241000 Anhui China Center for Molecular Recognition Columbia University New York NY 10032 Spice and Beverage Crops Research Institute Chinese Academy of Tropical Agricultural Sciences Wanning 571533 Hainan China

Abstract Spinal cord injury （SCI） remains an unsolved human health challenge. To alleviate the impairments of SCI, we studied the therapeutic effect of nimodipine （an L-type Ca^2＋ channel antagonist） on functional recovery from SCI using Nystrom＇s method in a mouse model. Eighty-four mice were divided into three groups： control group in which only vertebral plates were cut off without causing any spinal injuries; SCI; and SCI with nimodipine treatment. We assessed the histopathology, apoptosis detection, cell cycle, mitochondrial transmembrane potential, bcl-2/bax and caspase-3 levels of tissue 8 h, 1 d, 3 d and 4 d after trauma to evaluate rehabilitation. Behavioral performances were also assessed before and after nimodipine treatment. Results from inclined plane tests, motor score assessment and histological observations indicated that mice in the nimodipine-treated group rehabilitated better than those in the SCI group. The ratio of apoptosis, caspase-3 and bax expression in the nimodip- ine-treated group were significantly lower than those in the SCI group. The mitochondrial membrane potential and bcl-2 expression were up-regulated in the nimodipine-treated group. Taken together, our results indicate that the inhibition of calcium flux by nimodipine could reduce apoptosis processes and tissue damage through a mitochondrial pathway after spinal cord trauma [Current Zoology 57 （3）： 340-349, 2011].

关键词： Nimodipine Mitochondrial-pathway Alleviation Spinal cord injury Apoptosis

Flow separation control on swept wing with nanosecond pulse driven DBD plasma actuators

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Chinese Journal of Aeronautics 2015年第2期28卷 368-376页

作者： Zhao Guangyin li Yinghong liang hua Han Menghu Wu Yun Science and Technology on Plasma Dynamics Laboratory Air Force Engineering University

A 15° swept wing with dielectric barrier discharge plasma actuator is designed. Experimental study of flow separation control with nanosecond pulsed plasma actuation is performed at flow velocity up to 40 m/s. The effects of the actuation frequency and voltage on the aerodynamic performance of the swept wing are evaluated by the balanced force and pressure measurements in the wind tunnel. At last, the performances on separation flow control of the three types of actuators with plane and saw-toothed exposed electrodes are compared. The optimal actua- tion frequency for the flow separation control on the swept wing is detected, namely the reduced frequency is 0.775, which is different from 2-D airfoil separation control. There exists a threshold voltage for the low swept wing flow control. Before the threshold voltage, as the actuation voltage increases, the control effects become better. The maximum lift is increased by 23.1% with the drag decreased by 22.4% at 14°, compared with the base line. However, the best effects are obtained on actuator with plane exposed electrode in the low-speed experiment and the abilities of saw-toothed actuators are expected to be verified under high-speed conditions.

关键词： Dielectric barrier discharge Flow control Flow separation Nanosecond pulse Plasma Swept wing

NUMERICAL SIMULATION OF WAVE-INDUCED CURRENT WITH VERTICALLY VARIED RADIATION STRESS

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Journal of Hydrodynamics 2010年第2期22卷 254-259页

作者： ZHANG Jing lianG Bing-chen li hua-jun College of Engineering Ocean University of China Qingdao 266100 China

This article analyzes the vertical structure of the onshore current including the wave-induced current by an equation developed for the radiation stress against water depth.A coupled model COHERENS-SED is adopted to calculate the wave,tidal current,wave-induced current and sediment *** applying the new model to Yangpu Bay,its reliability is *** an ideal coastal domain is defined to simulate the nearshore current and wave setup with normal incident *** numerical and experimental results for the vertical structure show two undertows,also a visible setup in the surf *** demonstrates the importance of the radiation stress in wave-induced currents and mean water levels（set-up/down）.

关键词： COHERENS-SED radiation stress wave-induced current setup

Combined influence of nonlinearity and dilation on slope stability evaluated by upper-bound limit analysis

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Journal of Central South University 2017年第7期24卷 1602-1611页

作者： TANG Gao-peng ZHAO lian-heng li liang CHEN Jing-yu School of Civil Engineering Central South UniversityChangsha 410075China

The combined influence of nonlinearity and dilation on slope stability was evaluated using the upper-bound limit analysis *** mechanism of slope collapse was analyzed by dividing it into arbitrary discrete soil blocks with the nonlinear Mohr–Coulomb failure criterion and nonassociated flow *** multipoint tangent(multi-tangent) technique was used to analyze the slope stability by linearizing the nonlinear failure criterion.A general expression for the slope safety factor was derived based on the virtual work principle and the strength reduction technique,and the global slope safety factor can be obtained by the optimization method of nonlinear sequential quadratic *** results show better agreement with previous research result when the nonlinear failure criterion reduces to a linear failure criterion or the non-associated flow rule reduces to an associated flow rule,which demonstrates the rationality of the presented *** safety factors calculated by the multi-tangent inclined-slices technique were smaller than those obtained by the traditional single-tangent inclined-slices *** results show that the multi-tangent inclined-slices technique is a safe and effective method of slope stability limit *** combined effect of nonlinearity and dilation on slope stability was analyzed,and the parameter analysis indicates that nonlinearity and dilation have significant influence on the result of slope stability analysis.

关键词： slope stability analysis nonlinear failure criterion non-associated flow rule multipoint tangent technique upper-bound limit analysis theorem

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大角度波浪控制下的浪成砂坝新模式

石油与天然气地质 2024年第2期45卷 530-541页

作者：黎瑞杨娇柴愈坤王华戴建文邓永辉孙爽马肖琳田腾飞中海石油(中国)有限公司深圳分公司广东深圳518064

浪成砂坝为波浪改造后二次沉积产物,传统沉积模式认为其主要呈平行岸线条带状展布,但忽视了波浪入射角与岸线夹角的差异会导致沉积模式的巨大差异。结合珠江口盆地惠州凹陷以及青海湖现代浪成砂坝沉积特征,研究总结了大角度波浪控制下... 详细信息

浪成砂坝为波浪改造后二次沉积产物,传统沉积模式认为其主要呈平行岸线条带状展布,但忽视了波浪入射角与岸线夹角的差异会导致沉积模式的巨大差异。结合珠江口盆地惠州凹陷以及青海湖现代浪成砂坝沉积特征,研究总结了大角度波浪控制下的浪成砂坝差异沉积模式。结果表明:①受限于东沙隆起,惠州凹陷南缘局部区域存在显著的“峡谷效应”,波浪呈大角度入射,且由于沉积期发育位置不同导致的水动力环境不同,2个邻近油田砂体在沉积过程中受波浪改造后,形态和规模存在巨大差异。②引入海岸动力学沿岸输沙机理,结合野外地质考察成果,将浪成砂坝分为全封闭斜交岸线型、平行岸线型和半开放斜交岸线型3类,并提出了一种大角度波浪控制下的浪成砂坝新模式。③实钻结果证实,该模式下迎风翼和背风翼的砂坝形态、规模及叠置样式差异巨大,且砂体之间易形成“连而不畅”的岩性油气藏。新模式对指导浪成砂坝型储层的勘探与开发具有重要的理论与现实意义。

关键词：储层特征沉积模式浪成砂坝岩性油气藏珠江口盆地

Discovery and validation of prognostic markers in gastric cancer by genome-wide expression profiling

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World Journal of Gastroenterology 2011年第13期17卷 1710-1717页

作者： Yue-Zheng Zhang lian-Hai Zhang Yang Gao Chao-hua li Shu-Qinjia Ni liu Feng Cheng De-Yun Niu William CS Cho Jia-Fu Ji Chang-Qing Zeng Beijing Institute of Genomics Chinese Academy of Sciences Beijing 100029 China CAS Key Laboratory of Genome Sciences andInformation Chinese Academy of Sciences Beijing Institute ofGenomics Beijing 100029 China Graduate School of ChineseAcademy of Sciences Beijing 100049 China Key Labora-tory of Carcinogenesis and Translational Research (Ministry ofEducation) Department of Surgery Beijing Cancer Hospitaland Institute Peking University School of Oncology Beijing100142 China Department of Clinical Oncology QueenElizabeth Hospital Hong Kong China Laboratory of Cancer Genomics and Personalized Medicine Beijing Institute of Genomics ChineseAcademy of Sciences Beijing 100029 China

AIM: To develop a prognostic gene set that can predict patient overall survival status based on the whole genome expression analysis. METHODS: Using Illumina HumanWG-6 BeadChip followed by semi-supervised analysis, we analyzed the expression of 47 296 transcripts in two batches of gastric cancer patients who underwent surgical resection. Thirty-nine samples in the first batch were used as the training set to discover candidate markers correlated to overall survival, and thirty-three samples in the second batch were used for validation. RESULTS: A panel of ten genes were identified as prognostic marker in the first batch samples and classified patients into a lowand a high-risk group with significantly different survival times (P = 0.000047). This prognostic marker was then verified in an independent validation sample batch (P = 0.0009). By comparing with the traditional Tumor-node-metastasis (TNM) staging system, this ten-gene prognostic marker showed consistent prognosis results. It was the only independent prognostic value by multivariate Cox regression analysis (P = 0.007). Interestingly, six of these ten genes are ribosomal proteins, suggesting a possible association between the deregulation of ribosome related gene expression and the poor prognosis. CONCLUSION: A ten-gene marker correlated with overall prognosis, including 6 ribosomal proteins, was identified and verified, which may complement the predictive value of TNM staging system.

关键词： Gastric cancer Gene expression profiling Survival markers Prognosis Ribosomal proteins

In Situ Electron Backscatter Diff raction Analysis for Microstructure Evolution and Deformation Models of Mg–Ce Alloy During Uniaxial Loading

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Acta Metallurgica Sinica(English Letters) 2019年第2期32卷 263-268页

作者： Fang-Wei Jiao li Jin Jie Dong Feng-hua Wang National Engineering Research Center of light Alloys Net Forming School of Material Sciences and Engineering Shanghai Jiaotong University

Previous studies showed that signifi cant increases in elongation in Mg–Ce alloys due to the Ce addition and the solute drag eff ect by Ce addition were ascribed to the non-basal dislocation slip activating and the texture altering. The microstructure evolution and deformation models of extruded Mg-0.5 wt%Ce alloy rods under uniaxial tension have been studied using in situ electron backscatter diff raction. The basal and non-basal slips were characterized by using slip line trace analysis. The results provide evidence for that pyramidal slip activated during deformation, besides basal slip and extension twinning, which contributes to the texture weakening and ductility increasing in Mg-0.5 wt%Ce alloy.

关键词： Texture Non-basal slip Twinning In situ electron backscattered diff raction(EBSD) Trace analysis