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A Lectin from Chinese Mistletoe Increases γδ T Cell-mediated Cytotoxicity through Induction of Caspase-dependent Apoptosis

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Acta Biochimica et Biophysica Sinica 2007年第6期39卷 445-452页

作者： Fang GONG~1. Yanhui MA~1. Anlun MA~(1.3), Qiwen YU~1. Jiying ZHANG~1. Hong NIE~1. Xuehua chen~2, Baihua SHEN~1. Ningli LI~1. and Dongqing ZHANG~(1.) 1.Shanghai Jiaotong University School of Medicine. Shanghai Institute of Immunology, Shanghai 200025. China 2 Shanghai Institute of Digestive Surgery, Ruijin Hospital, Shanghai 200025, China 3 Centre de Rcherche du CHUM, Hopital Notre-Dame, Universite de Montreal. Montreal. Quebec H2L 4Ml, Canada Shanghai Jiaotong University School of Medicine Shanghai Institute of Immunologyshanghai 200025 China Centre de Rcherche du CHUM Hôpital Notre-Dame Université de Montréal MontréalQuébec H2L 4MI Canada Shanghai Institute of Digestive Surgery Ruijin Hospital Shanghai 200025China

In this study, a mistletoe lectin （ML） was purified from Chinese mistletoe and the effect of this 60 kDa Chinese ML on human γδ T cell cytotoxicity, apoptosis and modulation of the cytokine network was studied. The cytotoxic properties of δ T cells was evaluated by using a51.r release test and employed fluorescence-activated cell sorting and enzyme-linked immunosorbent assay analysis to quantify translocation of the cell membrane phospholipid, phosphatidylserine and nuclear DNA fragmentation during apoptosis. It was found that: （ⅰ） ML effectively stimulated γδ T cell proliferation in a dose- and time-dependent manner; （ⅱ） ML increased γδ T cell cytotoxicity; （ⅲ） ML could modulate lipopolysaccharide-induced cytokine release in a pro-inflammatory manner by increasing tumor necrosis factor （TNF）-α release and inhibiting the release of anti-inflammatory interleukin （IL）-1.; （ⅳ） ML induced apoptosis in caspase-dependent and CD95-independent manner. The results indicated that ML is a potent immunomodulator to human γδ T cell cytotoxicity, apoptosis and cytokine production.

关键词： mistletoe lectin γδ T cell cytotoxicity apoptosis cytokine

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Effect of ZrC Modified Graphite on Structure and Properties of Low-carbon Al_(2)O_(3)-C Refractories

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China's Refractories 2024年第1期33卷 18-22页

作者： HU chen WANG Xing LIU Zhenglong DING Jun YU Chao DENG chengji The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081China

To address the issues of reduced performance and shortened lifespan during the low-carbonizating process of Al_(2)O_(3)-C refractories,nano-crystalline ZrC modified graphite was prepared using Zr powder and flake graphite as raw materials,with NaCl and NaF mixed salt serving as the *** flake graphite was gradually replaced by ZrC modified graphite in the preparation of Al_(2)O_(3)-C refractories,and its impact on the material’s structure and properties was *** results indicate that,compared to samples with only flake graphite,the introduction of 1.mass%to 5 mass%nano-crystalline ZrC modified graphite can significantly enhance the mechanical performance of low-carbon Al_(2)O_(3)-C *** 5 mass%ZrC modified graphite is added,the mechanical properties of the samples are optimal,with the cold modulus of rupture and elastic modulus reaching 22.5 MPa and 65.0 GPa,respectively.

关键词： ZrC modified graphite low-carbon Al_(2)O_(3)-C refractories microstrcucture mechanical properties

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Computer simulation of rolling wear on bionic non-smooth convex surfaces

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Journal of Bionic Engineering 2004年第4期1卷 241-247页

作者： HAN Zhi-wu1. LIUZu-bin2, YANG zhuo-juan1. YAN Yu-ying3, REN Lu-quan1.1. Key Laboratory for Terrain-machine Bionics Engineering (Ministry of Education, China), Jilin University, Changchun 1.0022, P. R. China 2. Changchun Institute of Automobile, Changchun 1.0051. P. R. China 3. School of the Built Environment, The University of Nottingham, University Park, Nottingham NG7 2RD, UK 1 Key Laboratory for Terrain-machine Bionics Engineering (Ministry of Education China) Jilin University Changchun 130022 P. R. China Changchun Institute of Automobile Changchun 130051 P. R. China School of the Built Environment The University of Nottingham University Park Nottingham NG7 2RD UK

The study of bionics has found that the skins of many burrow animals which live in soil and stone conditions have an anti wear function, and which is related to their body surfaces’non-smooth morphology. In the present study, bionic non-smooth surfaces are used in roll surface design, and roll models with convex non-smooth surfaces are developed. The rolling wear of non-smooth roll in steel rolling is simulated by the FEM software-ANSYS. The equivalent stress, the node friction stress, and the node contact pressure between the roll and the rolling piece are calculated; and the anti-wear mechanism is analyzed.

关键词： bionics biomimetics non-smooth surface roll rolling wear FEM 1

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基于Q-POD的脉动背压下压气机流场特性

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内燃机学报 2024年第4期42卷 334-342页

作者：陈雪康施新胡晨星北京理工大学机械与车辆学院北京100081

针对一台自由活塞发动机(FPEG)匹配的电动压气机,研究了脉动背压条件下压气机的瞬态特性,并将脉动背压和稳定背压工况进行对比,揭示了压气机内部不同形成机理的非定常特征.采用四重本征正交模态分解(Q-POD)法,对压气机非定常流场进行了... 详细信息

针对一台自由活塞发动机(FPEG)匹配的电动压气机,研究了脉动背压条件下压气机的瞬态特性,并将脉动背压和稳定背压工况进行对比,揭示了压气机内部不同形成机理的非定常特征.采用四重本征正交模态分解(Q-POD)法,对压气机非定常流场进行了降阶重构.基于局部熵产率,对分解后的四重流场结构逐一分析,量化并定位了压气机非定常流动中的不可逆损失.结果表明:有/无脉动背压的熵产差异在叶轮中接近1.%,在压壳中仅为1..叶轮中的大尺度结构扰动耗散熵产占主导,扩压器中直接湍流耗散熵产占比超过92%.脉动背压通过改变压气机中大尺度相干结构进而影响瞬时流场结构.大尺度涡结构在环形通道内周向发展是造成扩压器中不可逆损失的主要因素.

关键词：压气机脉动背压四重本征正交模态分解不可逆损失熵产

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响应面法优化紫菀多糖提取工艺及抗氧化活性

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广州化工 2024年第6期52卷 115-119页

作者：蔡吉祥陈卓琳苏龙李大成赵海燕广西科技师范学院食品与生化工程学院广西来宾546119

为开发利用紫菀多糖资源,在单因素试验的基础上,通过响应面法优化了紫菀多糖的提取工艺,同时研究了紫菀多糖的抗氧化活性。结果表明:紫菀多糖的最佳工艺为微波时间1.6 s、微波功率600 W、液料比51.mL/g,在该工艺条件下紫菀多糖的得率为1...

为开发利用紫菀多糖资源,在单因素试验的基础上,通过响应面法优化了紫菀多糖的提取工艺,同时研究了紫菀多糖的抗氧化活性。结果表明:紫菀多糖的最佳工艺为微波时间1.6 s、微波功率600 W、液料比51.mL/g,在该工艺条件下紫菀多糖的得率为1..36%;紫菀多糖浓度在300μg/mL时,对DPPH·自由基的清除率可达89.71.,IC_(50)值为1.3.25μg/mL,紫菀多糖溶液在600μg/mL时,对·OH自由基的清除率达66.70%,IC_(50)值为424.1.μg/mL。

关键词：紫菀多糖响应面法微波辅助提取抗氧化活性

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基于源导向的土壤重金属风险评价及管控因子分析

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环境科学 2024年第2期45卷 1026-1037页

作者：潘泳兴陈盟王櫹橦桂林理工大学环境科学与工程学院桂林541004 广西岩溶地区水污染控制与用水安全保障协同创新中心桂林541004 桂林理工大学地球科学学院桂林541004

量化重金属来源风险可以识别主要污染源,为减轻土壤重金属对生态和人类健康风险提供科学依据.以桂北某铅锌矿流域浅层土壤为研究对象,利用潜在生态风险评价(RI)和人体健康风险评价(HRA)进行生态和人体健康风险评价,利用绝对主成分-多元... 详细信息

量化重金属来源风险可以识别主要污染源,为减轻土壤重金属对生态和人类健康风险提供科学依据.以桂北某铅锌矿流域浅层土壤为研究对象,利用潜在生态风险评价(RI)和人体健康风险评价(HRA)进行生态和人体健康风险评价,利用绝对主成分-多元线性回归受体(APCS-MLR)模型和随机森林模型进行土壤重金属源解析,最后结合RI、HRA和APCS-MLR组成联合风险评价模型量化土壤重金属来源风险.结果表明,ω(Pb)、ω(Zn)、ω(Cu)和ω(Cd)均值分别为342.77、693.34、61.27和3.08mg·kg^(-1.,含量均超出农用地土壤环境筛选值,存在一定程度的污染;Pb、Cr和As是主要健康风险影响因子,对儿童的健康风险要高于成年人;源解析结果识别出矿山开采活动(来源Ⅰ)、成土母质及原生地层(来源Ⅱ)和未知源,其中Pb、Zn、Cu和Cd主要由来源Ⅰ,Cr和As主要由未知源和来源Ⅱ贡献;土壤重金属来源风险评价结果表明,潜在生态风险和非致癌风险主要由来源Ⅰ和来源Ⅱ贡献,而致癌风险主要由未知源贡献;未知源在来源解析和风险评价均占有较高比例,应对其进一步研究,为土壤重金属防治提供科学依据.基于源解析的联合风险评价模型,注重不同来源的风险特征,精准查明高风险污染源,是一种更为合理可靠的风险评价方法.

关键词：土壤重金属生态风险健康风险联合风险评价模型源风险评价

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A Numerical Approach to Optimal Dividend Policies with Capital Injections and Transaction Costs

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Acta Mathematicae Applicatae Sinica 2017年第1期33卷 221-238页

作者： zhuo JIN Hai-liang YANG G.YIN Centre for Actuarial Studies Department of Economicsthe University of Melbourne Department of Statistics and Actuarial Science the University of Hong Kong Department of Mathematics Wayne State University

This work focuses on numerical methods for finding optimal dividend payment and capital injection policies to maximize the present value of the difference between the cumulative dividend payment and the possible capital injections. Using dynamic programming principle, the value function obeys a quasi-variational inequality （QVI）. The state constraint of the impulsive control gives rise to a capital injection region with free boundary. Since the closed-form solutions are virtually impossible to obtain, we use Markov chain approximation techniques to construct a discrete-time controlled Markov chain to approximate the value function and optimal controls. Convergence of the approximation algorithms is proved.

关键词： control singular control dividend policy capital injection free boundary Markov chain approx-imation

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非巨灾型地震Natech事件中储罐泄漏致多米诺效应动态演化分析

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中国安全生产科学技术 2024年第5期20卷 35-42页

作者：程方明蒋萌邓军罗振敏苏畅李卓西安科技大学安全科学与工程学院陕西西安710054 西安科技大学西安市城市公共安全与消防救援重点实验室陕西西安710054

为探究地震作用下地裂缝诱发的非巨灾型Natech事件对储罐泄漏火灾多米诺效应的影响,提出1.基于Natech情景假设的GERT-DBN演化分析模型。该模型将非巨灾型Natech事件的时空演化与概率预测相结合,基于量化的情景信息,明确组成多米诺事故... 详细信息

为探究地震作用下地裂缝诱发的非巨灾型Natech事件对储罐泄漏火灾多米诺效应的影响,提出1.基于Natech情景假设的GERT-DBN演化分析模型。该模型将非巨灾型Natech事件的时空演化与概率预测相结合,基于量化的情景信息,明确组成多米诺事故情景的主要失效储罐组合及其发生概率;在储罐受不同程度地裂缝损伤的失效情景假设下,获得多米诺效应升级概率伴随事故情景演化的变化规律,实现储罐多米诺事故升级概率的动态预测,并应用实例进行预测验证。研究结果表明:实例加氢站储罐组事故情景下,地震及其次生地裂缝损伤的增大与热辐射累积产生耦合作用会加速多米诺事故升级;多米诺事故升级概率在储氢罐失效前伴随事故演化逐渐下降;安全防护系统效用会一定程度上受到地裂缝损伤影响。研究结果可为非巨灾型地震Natech事件中的风险研判与管控工作提供参考。

关键词： Natech事件地裂缝多米诺效应动态贝叶斯网络(DBN) 非巨灾事件

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Discovery of Triassic coal-bearing strata in the Daxing'anling Region, Northeast China

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Science Bulletin 2024年第16期69卷 2471-2473页

作者： zhuolong Yang Pujun Wang Yulong Huang Youfeng Gao Chongyang {1. College of Earth Sciences Jilin UniversityChangchun 130061China Research Center of Palaeontology and Stratigraphy jilin UniversityChangchun 130026China College of Geographic Sciences and Tourism jilin Normal UniversitySiping 136000China

During the late Paleozoic to early Mesozoic,a tectonic transition occurred in Northeast China,marking a shift from the Paleo-Asian Ocean to the Mongolian Okhotsk and Paleo-Pacific tectonic domains[1..As a result of regional compression induced by oceanic closure and continental collision,stratigraphic records from this period are scarce,but such records are essential for elucidating the tectonic and paleographic evolution of the region during the transition.

关键词： Northeast tectonic strata

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Isotopic compositions of small shelly fossil Anabarites from Lower Cambrian in Yangtze Platform of South China: Implications for palaeocean temperature

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Progress in Natural Science:Materials International 2007年第10期17卷 1185-1191页

作者： chen Yongquan1.2, Jiang Shaoyong1. Ling Hongfei1. Yang Jinghong1.and Wan Defan3(1. State Key Laboatory for Mineral Deposits Research and Center for Marine Geochemistry Research, Department of Earth Sciences, Nanjing University, Nanjing 21.093, China 2. Tarim Oilfield Company Exploration & Development Research Institute, Ku’erle 841.00, China 3. Institute of Mineral Resources, Chinese Academy of Geological Sciences, Beijing 1.0037, China) State Key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China Exploration and Development Research Institute Tarim Oilfield Company Ku'erle 841000 China Institute of Mineral Resources Chinese Academy of Geological Sciences Beijing 100037 China

Anabarites belong to small shelly fossils (SSF), which occur widely in the Lower Cambrian strata of Yangtze Platform in South China. They are phosphate shell in composition and represent the earliest stage of the Cambrian bioradiation of Bilateria, the so-called "Cambrian Explosion". In this study, we attempted to separate Anabarites fossils from Lower Cambrian dolostones, and we obtained samples of both the fossils (SSF) and the granular phosphates (GP). Isotopic analyses were performed on samples of SSF, GP, and matrix dolostone (DH-23). The results showed that the δ30Si values of the quartz filling in fossils celoms, and the siliceous materials in granular phosphates are -0.6‰ and -0.7‰, which is different from normal sedimentary siliceous rocks from the Lower Cambrian strata (0—0.7‰) as reported by Li et al., but is consistent with the data for siliceous rocks and cherts of submarine hydrothermal origin. It is likely that a later hydrothermal replacement could have taken place in the SSF-bearing sedimentary rocks. The oxygen isotope values of the phosphate of SSF and GP are 1..8‰ and 1..0‰, respectively. These are significantly higher than the Neoproterozoic phosphate ores (1..9‰—1..9‰) as reported by Ling et al., hence, late diagenesis and hydrothermal replacement may not have caused a significant change in the oxygen isotope compositions of the small shelly fossils, and the calculated temperatures (25.4—26.3℃) for palaeo-seawater using a SSF phosphate oxygen isotope thermometer are therefore considered here as the upper limit of seawater temperature in the Early Cambrian ocean of the Yangtze Platform.

关键词： Anabarites oxygen isotope silicon isotope paleo-temperature.

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