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中国GVC分工深化对制造业出口国内增加值率的影响

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新疆财经大学学报 2024年第1期 20-30页

作者：何达开王维然新疆师范大学新疆乌鲁木齐830017

生产非一体化与贸易一体化的全球价值链分工格局下,出口贸易中增加值的属地与属权进一步分离,中间品贸易成为国际贸易的主要形式。在此背景下,生产分工深化能否提高国际贸易真实利得?文章使用UIBE-GVC数据库数据,基于前后向生产分工视角... 详细信息

生产非一体化与贸易一体化的全球价值链分工格局下,出口贸易中增加值的属地与属权进一步分离,中间品贸易成为国际贸易的主要形式。在此背景下,生产分工深化能否提高国际贸易真实利得?文章使用UIBE-GVC数据库数据,基于前后向生产分工视角,构建实证模型研究生产分工深化对出口国内增加值率(DVAR)的影响,结果显示:前向生产分工深化能够显著提高DVAR,后向生产分工深化则对DVAR产生抑制作用;前向生产分工深化对中技术制造业DVAR提高的促进作用最明显,后向生产分工深化则能够提高高技术制造业DVAR。基于此,今后应优化OFDI与FDI目的国与目,加大自主研发投入力度,掌握关键中间品核心技术,保障生产性服务业良好发展,提高以DVAR衡量的对外贸易利得。

关键词：前向生产分工深化后向生产分工深化 DVAR 中间品贸易 GVC

Effects of L-lactic acid and D,L-lactic acid on viability and osteogenic differentiation of mesenchymal stem cells

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Chinese Science Bulletin 2013年第20期58卷 2404-2412,1-3页

作者： HE Yao wang weiran DING JianDong State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular Science Advanced Materials Laboratory Fudan University

Poly(lactic acid) (PLA) and other aliphatic polyesters containing the unit of lactic acid are very popular biodegradable materials. While the degradation products, lactic acids, have been worried to bring with negative influence on biocompatibility, the focused experimental studies are less reported. This study is aimed at an in vitro examination of cytotoxicity of both L-lactic acid and D,L-lactic acid. Mesenchymal stem cells (MSCs) derived from rat bone marrow are employed to test the cytotoxicity of the lactic acids. Considering that the addition of lactic acids not only introduces lactate groups but also alters medium pH and ion strength, these three candidate effects are examined in a decoupled way by setting different comparison groups. The results confirm that the change of medium pH is the predominant factor. It has also been found that D-lactate is more cytotoxic than L-lactate at high concentrations. Yet, either L-or D,L-lactic acids seem acceptable in most of medical applications, because the cytotoxicity is significant only when the concentrations are as high as 20 mmol/L for both of them.

关键词：骨髓间充质干细胞 L-乳酸成骨分化细胞毒作用能力细胞毒性可生物降解生物相容性

基于UHPLC-Q-TOF-MS/MS的升麻素苷在正常大鼠和牙周炎模型大鼠体内外代谢研究

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中草药 2024年第12期55卷 4084-4098页

作者：张婉婉张子建杨梦华张洁茹张旭王伟然王春英河北医科大学药学院药物分析教研室河北石家庄050017 河北省中医院口腔科河北石家庄050011 新疆科技学院医学院新疆库尔勒841000

目的采用超高效液相色谱-四极杆-飞行时间质谱联用技术(UHPLC-Q-TOF-MS/MS)并结合多种数据后处理技术分析鉴定升麻素苷在正常大鼠及牙周炎模型大鼠体内外代谢物,并比较代谢差异。方法收集正常大鼠和模型大鼠新鲜粪便,探究升麻素苷在肠... 详细信息

目的采用超高效液相色谱-四极杆-飞行时间质谱联用技术(UHPLC-Q-TOF-MS/MS)并结合多种数据后处理技术分析鉴定升麻素苷在正常大鼠及牙周炎模型大鼠体内外代谢物,并比较代谢差异。方法收集正常大鼠和模型大鼠新鲜粪便,探究升麻素苷在肠道菌孵育体系中的体外代谢轮廓。正常及模型大鼠ig升麻素苷(100 mg/kg)后,分别于不同时间收集血浆、尿液、粪便、胆汁样本,合并相同样本,经适当方法进行处理后,采用COSMOCORE C_(18)柱(150 mm×2.1 mm,2.6μm),以0.1%甲酸水溶液(A)-甲醇(B)为流动相,梯度洗脱。在电喷雾离子源(electro-spray ionization,ESI)正离子模式下采集各生物样品的质谱数据,同时以右美沙芬为内标,采用峰面积相对定量法评估不同生物样品中代谢物的相对含量。结果初步鉴定出正常大鼠中代谢产物25个(其中I相代谢产物21个、II相代谢产物4个),牙周炎模型大鼠中代谢产物27个(其中I相代谢产物22个、II相代谢产物5个)。通过峰面积相对定量比较发现在不同病理状态下及不同生物样本中各代谢物含量存在显著差异,其中升麻素在各生物样品中的含量普遍较高。结论在不同病理状态下,同种化合物产生的代谢物种类及含量存在显著差异,模型动物的代谢研究更符合临床实际用药。升麻素可能是其在体内发挥抗炎、抗菌作用的药效物质。

关键词：升麻素苷升麻素牙周炎代谢 UHPLC-Q-TOF-MS/MS

Isolation of microsatellite loci and reliable genotyping using noninvasive samples of a critically endangered primate, Trachypithecus leucocephalus

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Integrative Zoology 2016年第4期11卷 250-262页

作者： weiran wang Yu QIAO Yitao ZHENG Meng YAO School of Life Sciences Peking UniversityBeijingChina

Genetic information can be critical in identifying conservation priorities and developing conservation *** is an urgent need for noninvasive genetic tools to study the wild populations of Asian colobine *** majority of these species are threatened with habitat destruction,population reduction and even extinction,but generally lack information on their genetic diversity and population *** sampling and tissue collection have been scarce in these species owing to strict regulations on manipulation of endangered species,and the difficulties and risks associated with capturing these arboreal and fast-moving monkeys in the challenging environments that they *** difficulties have hindered the development of molecular genetic markers,which are usually derived from tissues or *** this study,we present a method for de novo microsatellite isolation and genotyping using DNA from noninvasive origins of a critically endangered Asian colobine,the white-headed langur(Trachypithecus leucocephalus).Genomic DNA isolated from hair was shown to be sufficient for microsatellite enrichment and isolation,with similar isolation efficiencies as from tissue *** identified and characterized 20 polymorphic microsatellite loci,and evaluated their amplification success and genotyping reliability with 86 field-collected fecal *** results show that this panel of loci can produce reliable genotypes from fecal samples,and represent a useful tool for noninvasive investigation of genetic structure,individual identification and kinship assessment in this highly endangered *** approach can be applied to conservation genetic studies of other wild species that lack sequence information and tissue samples.

关键词： Asian colobine conservation genetics FIASCO hair scatology

基于模型预测的海缆铺设用水下航行器最优避障控制

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中国舰船研究 2024年第1期19卷 248-255页

作者：苏哲昊王伟然戴晓强朱志宇姚杰葛慧林江苏科技大学自动化学院江苏镇江212100

[目的]自主水下航行器(AUV)在海底复杂地形环境下执行独立铺缆作业时,需要兼顾铺缆质量和自身安全,即在避障的同时还需要保持船体与海底平面的相对高度。为此,设计一种基于模型预测的海缆铺设AUV最优避障控制方法。[方法]首先,基于模型... 详细信息

[目的]自主水下航行器(AUV)在海底复杂地形环境下执行独立铺缆作业时,需要兼顾铺缆质量和自身安全,即在避障的同时还需要保持船体与海底平面的相对高度。为此,设计一种基于模型预测的海缆铺设AUV最优避障控制方法。[方法]首先,基于模型预测控制(MPC)建立AUV的路径跟踪模型,将海底不规则障碍物分类为凸起和凹陷地形,并分别建立障碍物的工程简化数学模型;然后,根据不同地形和海缆铺设要求来设计多个目标优化函数;最后,根据地形特征点迭代计算与海底平面保持稳定高度且路径最短的最优避障路径。[结果]仿真结果表明,该方法响应性能好、可靠性高,能够使AUV选择最短路径并避开意外障碍物。[结论]在复杂的海底环境下,该方法既保障了AUV作业过程中的自身安全,又极大提高了海缆的铺设质量。

关键词：自主水下航行器模型预测控制海缆铺设最优避障控制

基于数据挖掘、网络药理和分子对接分析中药组方专利治疗奶牛乳房炎的作用机制

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畜牧与兽医 2024年第6期56卷 63-71页

作者：吴德胜王伟然丁金雪胡梦馨孟晋武王文佳刘家国南京农业大学动物医学院江苏南京210095 宁夏大学动物科技学院宁夏银川750021

旨在分析专利中复方中药治疗奶牛乳房炎的用药规律及作用机制。筛选并建立相关中药组方专利的数据库,进行频次、性味、归经、关联规则和高频药物聚类分析。通过在线数据库和相关文献获得核心药对活性成分和奶牛乳房炎的相关靶点。采用ST... 详细信息

旨在分析专利中复方中药治疗奶牛乳房炎的用药规律及作用机制。筛选并建立相关中药组方专利的数据库,进行频次、性味、归经、关联规则和高频药物聚类分析。通过在线数据库和相关文献获得核心药对活性成分和奶牛乳房炎的相关靶点。采用STRING数据库构建蛋白-蛋白互作信息网络,应用DAVID数据库进行基因本体(GO)功能和京都基因与基因组百科全书(KEGG)通路富集分析。将获得的核心药物和核心靶点进行分子对接验证。结果:共纳入178个专利组方,药性以寒、温为主,药味以苦、甘、辛为主,归经主入肝、肺、胃经,关联规则分析出14组药物组合,聚类分析将药物分为4类。核心药对蒲公英-紫花地丁和奶牛乳房炎共同靶点28个,主要富集于56条GO和72条KEGG信号通路。分子对接结果显示6个核心靶点与5种活性成分均具有结合的可能性。专利组方治疗奶牛乳房炎主要以清热解毒、益气活血调经、行气止痛等治法为主。核心药对可通过磷酸酯酶与张力蛋白同源物(PTEN)、V-rel网状内皮细胞病毒癌基因同源物A(RELA)、白细胞介素-6(IL-6)、白细胞介素-1β(IL-1β)、白细胞介素-2(IL-2)和γ干扰素(IFNG)等靶点调控白细胞介素-17(IL-17)、肿瘤坏死因子(TNF)、核因子κB(NF-κB)、PI3K-Akt和NOD样受体等信号通路,发挥抗炎、免疫调节等作用来防治奶牛乳房炎。

关键词：乳房炎网络药理分子对接中药专利

co-Condensation Synthesis of Salicylaldimine Calcium Complex Containing Mesoporous Silica Nanoparticles as Carriers for Drug Release

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Chemical Research in Chinese Universities 2014年第4期30卷 531-537页

作者： TANG Duihai ZHANG weiran wang Yifan MIAO Jing QIAO Zhen'an HUO Qisheng ZHANG Lirong State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A series of functional mesoporous silica nanoparticles（MSNs） was synthesized by a one-step simple synthesis approach involving co-condensation of tetraethoxysilane（TEOS） and salicylaldimine ligand（Sal-Si） in the presence of cetyltrimethylammonium chloride（CTAC） under basic *** target MSNs with different sizes （50,100 and 200 nm,respectively） were ***,the Ca^2＋ cations were also introduced into *** prepared nanoparticles were characterized by means of infrared（IR） spectra,thermogravimetric analysis（TGA）,inductively coupled plasma（ICP）,CHN elemental analysis,nitrogen adsorption-desorption,scanning electron microscope（SEM） and transmission electron microscope（TEM）.Ibuprofen（IBU） which contains carboxyl groups was selected as a model *** results of drug loading and release reveal that the loading capacities and release behaviors of the model drug are highly dependent on the Ca^2＋ cations in *** release of IBU from the MSNs functionalized by Ca^2＋ cations is found to be effectively controlled when compared to the release from the MSNs without the functionalization of Ca^2＋ cations,which is due to the ionic interaction between carboxyl groups in IBU and Ca^2＋ cations in MSNs.

关键词： Mesoporous silica nanoparticle co-Condensation method Release of ibuprofen Calcium ion

Continuous advantage learning for minimum-time trajectory planning of autonomous vehicles

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Science China(Information Sciences) 2024年第7期67卷 285-294页

作者： Zhuo LI weiran WU Jialin wang Gang wang Jian SUN School of Automation Beijing Institute of Technology Beijing Institute of Technology Chongqing Innovation Center China Academy of Launch Vehicle Technology Intelligent Game and Decision Laboratory

This paper investigates the minimum-time trajectory planning problem of an autonomous vehicle. To deal with unknown and uncertain dynamics of the vehicle, the trajectory planning problem is modeled as a Markov decision process with a continuous action space. To solve it, we propose a continuous advantage learning(CAL) algorithm based on the advantage-value equation, and adopt a stochastic policy in the form of multivariate Gaussian distribution to encourage exploration. A shared actor-critic architecture is designed to simultaneously approximate the stochastic policy and the value function, which greatly reduces the computation burden compared to general actor-critic methods. Moreover, the shared actor-critic is updated with a loss function built as mean square consistency error of the advantage-value equation, and the update step is performed several times at each time step to improve data efficiency. Simulations validate the effectiveness of the proposed CAL algorithm and its better performance than the soft actor-critic algorithm.

关键词： trajectory planning continuous advantage learning stochastic policy shared actor-critic

Effect of ambient pressures on laser-induced breakdown spectroscopy signals

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Frontiers of physics 2024年第4期19卷 243-256页

作者： Kaifan Zhang weiran Song Zongyu Hou Zhe wang State Key Laboratory of Power System Operation and Control Tsinghua-Rio Tinto Joint Research Centre for ResourcesEnergy and Sustainable DevelopmentInternational Joint Laboratory on Low Carbon Clean Energy InnovationInstitute for Carbon NeutralityDepartment of Energy and Power EngineeringTsinghua UniversityBeijing 100084China Shanxi Research Institute for Clean Energy Tsinghua UniversityTaiyuan 030032China

Laser-induced breakdown spectroscopy(LIBS)is regarded as the future superstar for analytical chemistry and widely applied in various *** the quality of LIBS signal is fundamental to achieving accurate quantification and large-scale commercialization of *** propose control methods that improve LIBS signal quality,it is essential to have a comprehensive understanding of the influence of key parameters,such as ambient gas pressure,temperature,and sample temperature on LIBS *** date,extensive research has been carried ***,different researchers often yield significantly different experimental results for LIBS,preventing the formation of consistent *** greatly prevents the understanding of influencing laws of key parameters and the improvement of LIBS quantitative *** ambient gas pressure as an example,this paper compares the effects of ambient gas pressure under different optimization conditions,reveals the influence of spatiotemporal window caused by inherent characteristics of LIBS signal sources,i.e.,intense temporal changes and spatial non-uniformity of laser-induced plasmas,on the impact patterns of key *** the perspective of plasma spatiotemporal evolution,the paper elucidates the influence patterns of ambient gas pressure on LIBS signals,clarifying seemingly contradictory research results in the literature.

关键词： laser-induced breakdown spectroscopy spatiotemporal window pressure condition signal uncertainty plasma modulation