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Synthesis of 2S-Hydroxymethyl-3R, 4R-dihydroxypyrrolidine

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Chinese Chemical Letters 1999年第8期10卷 651-652页

作者： Zhen CHEN ren yun wang Li Lian ZHU Xiao Tian LIANG (Institute of Materia Medica. Peking Union Medical College) (The Chinese Academy of Medical Sciences, Bejing 100050) Chinese Acad Med Sci Inst Mat Med Peking Union Med Coll Beijing 100050 Peoples R China

The sythesis of 2S-hydroxymethyl-3R, 4R-dihydroxypyrrolidine from D-arabinose was described in this paper.

关键词： polydroxylated pyrrolidine 2S-hydroxymethyl-3R 4R-dihydroxypyrrolidine D-arabinose

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新世界主义视野下的中国传媒发展

编辑之友 2017年第1期 5-12页

作者：邵培仁王昀浙江大学传媒与国际文化学院浙江杭州310028

近年来,中国关于"世界"的论述,体现出一种新世界主义视野。特别是"一带一路"作为当前国家主导叙事,不仅激活了新的媒介地理想象,并且正演变为颇具代表性的世界主义话语,预示中国国际传播顶层决策正在不断调试、探索新的路径和面向。因此... 详细信息

近年来,中国关于"世界"的论述,体现出一种新世界主义视野。特别是"一带一路"作为当前国家主导叙事,不仅激活了新的媒介地理想象,并且正演变为颇具代表性的世界主义话语,预示中国国际传播顶层决策正在不断调试、探索新的路径和面向。因此,传媒在呈现"一带一路"的角色表达时,必须关注其中涵盖的多重机理以适应国家抉择:"一带一路"既牵涉历史性的共同体叙事,又是本土性框架过滤的产物;其以现代化观念作为全球共识策略,亦透过地缘化布局展开治理机制。"一带一路"自身作为复杂的世界主义想象的被接受过程,也将内在驯化中国传媒产制,使之丰富本土的世界认知,推动制度优化与经验对话,重新反思全球化、区域化中的信息资源分配网络以及文化地理认同路径,从而进一步考量中国国际传播的未来空间。

关键词：世界主义中国传媒一带一路地理想象

Down-regulation of chloride cotransporter KCC2 involves in CTZ induced epilepsy

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Down-regulation of chloride cotransporter KCC2 involves in C...

中国神经科学学会第九届全国学术会议暨第五次会员代表大会

作者： Lu-Lan CHEN,Zheng WU,Li WAN,Wan-Ting ren,yun wang~* Institutes of Brain Science and State Key Laboratory for Medical Neurobiology,Fudan University,Shanghai 200032, China

GABA receptor-mediated inhibition depends on the maintenance of intracellular[CI]at low levels. The neuron specific K-C1 cotransporter KCC2 plays a pivotal role in neuronal inhibition by extruding CI and renders GABA and glycine action ***,KCC2 expression levels are reduced in various pathological conditions,including chronic pain,spinal cord injury,epilepsy and so on,with a resultant increased[CI] and a shift of GABA-mediated responses from hyperpolarizing to *** work from our lab has shown that cyclothiazide(CTZ) induced seizure behavior in conscious rats and epileptiform activity in hippocampal neurons. In the present study,by using immunohistochemistry and western blot,we found the density labeling and the amount of KCC2 of the somatic membrane was reduced in the hippocampus 1d after CTZ induced acute epilepsy model. In cultured hippocampal neurons 48h after CTZ treatment,immunocytochemistry analyses by confocal and high resolution microscopy also revealed the down regulation of KCC2 signal at the plasma to *** addition, patch clamp results also demonstrated that CTZ that induced E upshift and reduced CI extrusion ability in CA1 pyramidal neurons of inhippocampal slice,which was consistent with the result of molecular manipulated KCC2 down regulated cultured hippocampal ***,our data indicate that during CTZ induced epilepsy,plasma KCC2 was down regulated and function was inhibited.

关键词： CTZ epilepsy hippocampus KCC2 GABAA receptor

来源： cnki会议评论

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抗幽门螺旋杆菌三联疗法费用—效果分析

天津药学 2000年第3期12卷 54-56页

作者：任耘王彭天津医科大学总医院天津300052

目的：探讨不同抗幽门螺旋杆菌感染药物临床治疗方案的经济效果，找出即经济又有效的方案。方法：根据文献选择 3种不同的治疗方案 (BMA：德诺＋甲哨唑＋阿莫西林，疗程 2周； LMC：达克普龙＋甲硝唑＋利迈先，疗程 1周； RMA：雷尼替... 详细信息

目的：探讨不同抗幽门螺旋杆菌感染药物临床治疗方案的经济效果，找出即经济又有效的方案。方法：根据文献选择 3种不同的治疗方案 (BMA：德诺＋甲哨唑＋阿莫西林，疗程 2周； LMC：达克普龙＋甲硝唑＋利迈先，疗程 1周； RMA：雷尼替丁＋甲硝唑＋阿莫西林，疗程 2周 )，应用药物经济学中费用-效果分析法。结果： 3种方案所需药品费用分别为 203.84， 618.96和 112.96元；对幽门螺旋杆菌的根除率分别为 88.79％， 93.10％和 89.02％；费用-效果比分别为 2.30， 6.65和 1.26。结论：雷尼替丁三联疗法疗效较好，副作用少，费用低廉。

关键词：幽门螺旋杆菌三联疗法费用--效果分析

Towards Interpretable Defense Against Adversarial Attacks via Causal Inference

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Machine Intelligence Research 2022年第3期19卷 209-226页

作者： Min ren yun-Long wang Zhao-Feng He University of Chinese Academy of Sciences Beijing 100190China Center for Research on Intelligent Perception and Computing National Laboratory of Pattern RecognitionInstitute of AutomationChinese Academy of SciencesBeijing 100190China Laboratory of Visual Computing and Intelligent System Beijing University of Posts and TelecommunicationsBeijing 100876China

Deep learning-based models are vulnerable to adversarial attacks. Defense against adversarial attacks is essential for sensitive and safety-critical scenarios. However, deep learning methods still lack effective and efficient defense mechanisms against adversarial attacks. Most of the existing methods are just stopgaps for specific adversarial samples. The main obstacle is that how adversarial samples fool the deep learning models is still unclear. The underlying working mechanism of adversarial samples has not been well explored, and it is the bottleneck of adversarial attack defense. In this paper, we build a causal model to interpret the generation and performance of adversarial samples. The self-attention/transformer is adopted as a powerful tool in this causal model. Compared to existing methods, causality enables us to analyze adversarial samples more naturally and intrinsically. Based on this causal model, the working mechanism of adversarial samples is revealed, and instructive analysis is provided. Then, we propose simple and effective adversarial sample detection and recognition methods according to the revealed working mechanism. The causal insights enable us to detect and recognize adversarial samples without any extra model or training. Extensive experiments are conducted to demonstrate the effectiveness of the proposed methods. Our methods outperform the state-of-the-art defense methods under various adversarial attacks.

关键词： Adversarial sample adversarial defense causal inference interpretable machine learning transformers

Effects of neutral salt and alkali on ion distributions in the roots,shoots,and leaves of two alfalfa cultivars with differing degrees of salt tolerance

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Journal of Integrative Agriculture 2017年第8期16卷 1800-1807页

作者： wang Xiao-shan ren Hai-long WEI Zen-wu wang yun-wen ren Wei-bo Department of Grassland Science College of Animal Science and TechnologyYangzhou UniversityYangzhou 225009P.R.China Institute of Grassland Research Chinese Academy of Agricultural SciencesHohhot 010000P.R.China Department of Grassland Science College of Animal Science and TechnologyChina Agricultural UniversityBeijing 100193P.R.China

The effects of neutral salt and alkali on the ion distribution were investigated in two alfalfa （Medicago sativa L.） cultivars, including Zhongmu 1, a high salt-tolerant cultivar, and Algonquin, a low salt-tolerant cultivar. The alkali stress expressed more serious growth inhibition than the neutral salt stress at the same Na＋ concentration. Compared with Algonquin, Zhongmu 1 did not exhibit a higher alkali tolerance under the Na2CO3-NaHCO3 treatment with the low Na＋ concentration （50 mmol L-l）. The alkali increased the accumulation of Na＋, Ca2＋, and Mg2＋ in the root and changed the Ca2＋ and Mg2＋ balance in the entire alfalfa plant. The salt and alkali stresses decreased the K＋ and Fe3＋ contents of the roots and leaves, the root Mn2＋ content, and the shoot Zn2＋ content, but they increased the Fe3＋ accumulation of the shoots, the shoot and leaf Cu2＋ contents, and the leaf Zn2＋ content in both alfalfa cultivars. Based on the results obtained under the conditions of this experiment, we found that the salt and alkali stresses reduced the plant growth in both alfalfa cultivars, while the alkali caused a stronger stress than the neutral salt in alfalfa. Thus, we conclude that under hydroponic conditions, the deleterious effects of the alkali on plants are due to the distribution change of some trophic ion balance in the roots, shoots, and leaves of the plants by causing of Na＋, CO3^2-, and/or HCO3- stresses.

关键词： alfalfa ion distribution neutral salts alkali stress

Development of N-doped carbons from zeolite-templating route as potential electrode materials for symmetric supercapacitors

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International Journal of Minerals,Metallurgy and Materials 2018年第12期25卷 1482-1492页

作者： Meng ren Cheng-yun Zhang Yue-lin wang Jin-jun Cai Hunan Key Laboratory of Environment Friendly Chemical Process Technology School of Chemical Engineering Xiangtan University State Key Laboratory of Powder Metallurgy Central South University School of Engineering Materials & Science Queen Mary University of London

N-doped carbons were fabricated from zeolite-templated carbon via modification with melamine and mild KOH activation. The N-doping treatment and KOH activation slightly lowered the surface areas of pristine zeolite-templated carbon; nonetheless, N-doped carbons with a lower surface area exhibited much higher capacitance and cycling stability as fabricated into symmetric supercapacitor. Significantly, N-doped carbon obtained at 700°C showed a capacitance of 45.7 F/g at 0.1 A/g and 42.0 F/g at 10 A/g for the fabricated supercapacitor with 6 M KOH electrolyte, with 92% retention of initial capacitance as current density increased up to 100-fold. This performance was attributed to the dual contribution of electric double-layer capacitance and pseudo-capacitance. The assembled supercapacitor also exhibited excellent cycling stability, with 91% capacitance retention at 10 A/g after 10000 cycles.

关键词： zeolite template porous carbon nitrogen-doping chemical activation supercapacitor

Input-output approach to robust stability and stabilization for uncertain singular systems with time-varying discrete and distributed delays

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第4期9卷 546-551页

作者： Hui-jiao wang An-ke XUE yun-fei GUO ren-quan LU Institute of Automation Zhej iang Sci- Tech University Hangzhou 310018 China Institute of Information and Control Hangzhou Dianzi University Hangzhou 310018 China

Based on input-output approach, the robust stability and stabilization problems for uncertain singular systems with time-varying delays are investigated. The parameter uncertainties are assumed to be norm-bounded and the time-varying delays include both discrete delay and distributed delay. By introducing a new input-output model, the time-delay system is embedded in a family of systems with a forward system without time delay and a dynamical feedback uncertainty. A sufficient and necessary condition, which guarantees the system regular, impulse-free and stable for all admissible uncertainties, is obtained. Based on the strict linear matrix inequality, the desired robust state feedback controller is also obtained. Finally, a numerical example is provided to demonstrate the application of the proposed method.

关键词： Robust stability Input-output stability Singular system Time-varying delay Linear matrix inequality (LMI)

塔玛亚历山大藻对黑褐新糠虾存活、生长以及种群繁殖的影响

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生态学报 2002年第10期22卷 1635-1639页

作者：谭志军颜天周名江李钧于仁诚王云峰中国科学院海洋研究所海洋生态与环境重点实验室青岛266071

通过塔玛亚历山大藻 ( Alexandrium tamarense)对黑褐新糠虾 ( N eomysis awatschensis)的急性和慢性毒性作用研究 ,发现塔玛亚历山大藻对黑褐新糠虾的存活、生殖、生长等有不利影响 ,影响程度随塔玛亚历山大藻藻细胞密度的增加而增加。... 详细信息

通过塔玛亚历山大藻 ( Alexandrium tamarense)对黑褐新糠虾 ( N eomysis awatschensis)的急性和慢性毒性作用研究 ,发现塔玛亚历山大藻对黑褐新糠虾的存活、生殖、生长等有不利影响 ,影响程度随塔玛亚历山大藻藻细胞密度的增加而增加。在 96 h急性毒性实验中 ,塔玛亚历山大藻对黑褐新糠虾的半致死密度为 70 0 0 cells/ml,去藻过滤液中糠虾的死亡率为 2 5 %。在 6 2 d的慢性毒性实验中 ,密度为 90 0 cells/ml的塔玛亚历山大藻对黑褐新糠虾的繁殖有严重影响 ,在此影响下的实验组亲虾产幼虾总数只有 2 7尾 ,仅为对照组产幼虾数目的 1 6 .4 % ;其总产幼虾天数、日最高产幼数分别只有对照的 32 %、4 1 % ,其初次产虾日期也推迟了 3d,并出现了 3次生殖中断。塔玛亚历山大藻对黑褐新糠虾亲虾的存活、生长也有一定的影响 ,处在密度为 90 0 cells/ml塔玛亚历山大藻中的黑褐新糠虾亲虾的存活率只有对照的 6 3% ,糠虾亲虾的体长和体重分别为对照组亲虾的 95 .6 %和 81 .9% ,但差异尚不显著 ( P>0 .0 5 )

关键词：塔玛亚历山大藻黑褐新糠虾存活生长赤潮甲藻毒性危害种群繁殖