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数字金融发展与企业产能利用率:基于沪深A股上市公司的实证研究

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金融发展研究 2024年第1期 35-43页

作者：刘兴华吴晟婕江西财经大学金融学院江西南昌330013

基于2011—2021年A股上市公司样本数据,探讨数字金融发展对企业产能利用率的影响机理。研究发现,数字金融发展能够显著提高企业的产能利用率,促进技术创新、改善资源错配和抑制过度投资是数字金融发展提高企业产能利用率的作用渠道。异... 详细信息

基于2011—2021年A股上市公司样本数据,探讨数字金融发展对企业产能利用率的影响机理。研究发现,数字金融发展能够显著提高企业的产能利用率,促进技术创新、改善资源错配和抑制过度投资是数字金融发展提高企业产能利用率的作用渠道。异质性分析发现,数字金融发展对企业产能利用率的提升作用在融资约束较大企业、高科技企业及市场化程度较低地区企业中表现得更为明显。适当的金融监管能够引导数字金融正外部性的发挥,助力数字金融发展对企业产能利用率的提升作用。据此提出大力推进数字金融发展、深化供给侧结构性改革、增强数字金融监管力度和提升企业质量管理能力等政策建议。

关键词：数字金融产能利用率信息不对称过度投资金融监管

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基于梯度提升的优化集成机器学习算法对滑坡易发性评价:以雅鲁藏布江与尼洋河两岸为例

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西北地质 2024年第1期57卷 12-22页

作者：林琴郭永刚吴升杰臧烨祺王国闻西藏农牧学院水利土木工程学院西藏林芝860000

雅鲁藏布江与尼洋河两岸地质构造活跃,山体滑坡时常发生,滑坡易发性评价能有效的减少因灾害发生所造成的对人类生命和财产的伤害。笔者基于基尼系数的加权随机森林、XGBoost和LightGBM算法在滑坡易发性中的性能。选取188个滑坡样本和7... 详细信息

雅鲁藏布江与尼洋河两岸地质构造活跃,山体滑坡时常发生,滑坡易发性评价能有效的减少因灾害发生所造成的对人类生命和财产的伤害。笔者基于基尼系数的加权随机森林、XGBoost和LightGBM算法在滑坡易发性中的性能。选取188个滑坡样本和7个影响因素,应用五折交叉验证法训练模型,训练过程中同时考虑特征选择算法、运用贝叶斯方法优化超参数后,采用precision、recall、F1、Accuracy指标对各个级别的预测结果进行分析。结果表明:在高程为32~1544 m与2722~3752 m、坡度为30°~40°、距断裂带、河流与道路200 m以内的区域最容易发生滑坡;滑坡极高与高易发性分布为12.14%和12.41%,低和极低易发性占比分别为26.47%与29.55%,区内一半以上的地区不容易发生滑坡灾害;LightGBM模型在所有模型中表现最好,AUC值为0.8432,准确度为0.8531,F1分数为0.8345;墨脱县的达木乡、帮辛乡,林芝县的丹娘、里龙、扎西饶登乡,朗县的陇村,工布江达的江达乡位于极高易发区,发生滑坡概率极大,在这些地区应采取相应的地质灾害防治措施。

关键词：梯度提升 XGBoost LightGBM 机器学习滑坡易发性

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主从遥操作机械手工作空间覆盖控制策略研究

机床与液压 2024年第2期52卷 18-24页

作者：李强曾宇飞武圣杰张华良沈阳工业大学机械工程学院辽宁沈阳110870 中国科学院沈阳自动化研究所辽宁沈阳110017

针对遥操作机器人主控制器工作空间过小和主从手工作空间不匹配的问题,提出一种区域覆盖思路。将主控制器工作空间与从机械手工作空间一一对应的映射关系转换成主手工作空间多次区域映射的关系,通过多次建立主从手的连接,达到区域覆盖... 详细信息

针对遥操作机器人主控制器工作空间过小和主从手工作空间不匹配的问题,提出一种区域覆盖思路。将主控制器工作空间与从机械手工作空间一一对应的映射关系转换成主手工作空间多次区域映射的关系,通过多次建立主从手的连接,达到区域覆盖的目的。同时为了更好地控制从机械手末端的姿态,设计一种相对运动姿态控制方法,将传递给机械手的绝对姿态坐标替换成姿态运动信息,以达到相对姿态控制目的。最后,进行仿真分析和试验验证。结果表明:该方法能够实现工作空间完美覆盖,主手能够有效地控制从手运动。

关键词：主从遥操作机械手位姿控制区域覆盖

Spatio-temporal delivery of both intra-and extracellular toll-like receptor agonists for enhancing antigen-specific immune responses

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Acta Pharmaceutica Sinica B 2022年第12期12卷 4486-4500页

作者： Nannan Wang Yueyue Zuo shengjie wu Chenlu Huang Linhua Zhang Dunwan Zhu Tianjin Key Laboratory of Biomedical Materials Key Laboratory of Biomaterials and Nanotechnology for Cancer ImmunotherapyInstitute of Biomedical EngineeringChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300192China

For cancer immunotherapy,triggering toll-like receptors(TLRs)in dendritic cells(DCs)can potentiate antigen-based immune ***,to generate robust and long-lived immune responses,a well-designed nanovaccine should consider different locations of TLRs on DCs and co-deliver both antigens and TLR agonist combinations to synergistically induce optimal antitumor ***,we fabricated lipid-polymer hybrid nanoparticles(LPNPs)to spatio-temporally deliver model antigen ovalbumin(OVA)on the surface of the lipid layer,TLR4 agonist monophosphoryl lipid A(MPLA)within the lipid layer,and TLR7 agonist imiquimod(IMQ)in the polymer core to synergistically activate DCs by both extra-and intra-cellular TLRs for enhancing adaptive immune ***-based nanovaccines exhibited a narrow size distribution at the mean diameter of 133.23 nm and zeta potential of−2.36 mV,showed a high OVA loading(around 70.83μg/mg)and IMQ encapsulation efficiency(88.04%).Our data revealed that LPNPs-based nanovaccines showed great biocompatibility to immune cells and an excellent ability to enhance antigen internalization,thereby promoting DCs maturation and cytokines *** to Free OVA,OVA-LPNPs promoted antigen uptake,lysosome escape,depot effect and migration to secondary lymphatic *** vivo immunization showed that IMQ-MPLA-OVA-LPNPs with dual agonists induced more powerful cellular and humoral immune ***,prophylactic vaccination by IMQ-MPLA-OVA-LPNPs effectively suppressed tumor growth and increased survival ***,the nanovaccines we fabricated can effectively co-deliver antigens and different TLR agonists and realize coordinated stimulation of DCs in a spatio-temporal manner for enhanced immune responses,which provides a promising strategy for cancer immunotherapy.

关键词： Lipid-polymer hybrid nanoparticles TLR agonist combinations Ovalbumin Monophosphoryl lipid AImiquimod Nanovaccine Spatio-temporal manner Cancer immunotherapy

Ultra-precision machining of cerium-lanthanum alloy with atmosphere control in an auxiliary device

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Nanotechnology and Precision Engineering 2022年第3期5卷 30-35页

作者： Chenyu Zhao shengjie wu Min Lai State Key Laboratory of Precision Measuring Technology and Instruments Laboratory of Micro/Nano Manufacturing TechnologyTianjin UniversityTianjin 300072China

Cerium–lanthanum alloys are the main component of nickel–metal hydride batteries,and they are thus an important material in the greenenergy ***,these alloys have very strong chemical activity,and their surfaces are easily oxidized,leading to great difficulties in their *** improve the corrosion resistance of cerium–lanthanum alloys,it is necessary to obtain a nanoscale surface with low ***,these alloys can easily succumb to spontaneous combustion during ***,to inhibit the occurrence of fire,machining of this alloy in ambient air needs to be conducted at very low cutting speeds while spraying the workpiece with a large amount of cutting ***,this is inefficient,and only a very limited range of parameters can be optimized at low cutting speeds;this restricts the optimization of other cutting *** achieve ultraprecision machining of cerium–lanthanum alloys,in this work,an auxiliary machining device was developed,and its effectiveness was *** results show that the developed device can improve the cutting speed and obtain a machined surface with low *** device can also improve the machining efficiency and completely prevent the occurrence of spontaneous *** was found that the formation of a build-up of swarf on the cutting tool is eliminated with high-speed cutting,and the surface roughness(Sa)can reach 5.64 nm within the selected ***,the oxidation processes of the cerium–lanthanum alloy and its swarf were studied,and the process of the generation of oxidative products in the swarf was *** results revealed that most of the intermediate oxidative products in the swarf were Ce^(3+),there were major oxygen vacancies in the swarf,and the final oxidative product was Ce^(4+).

关键词： Cerium–lanthanum alloy Ultraprecision machining Surface roughness Atmosphere control

Stress-strain behavior of multi-phase high performance structural steel

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Science China(Technological Sciences) 2012年第7期55卷 1791-1796页

作者： NIE WenJin WANG XueMin wu shengjie GUAN HaiLong SHANG ChengJia School of Materials Science and Engineering University of Science and Technology BeijingBeijing 100083China Jiangsu Shasteel Group Co.Ltd Zhangjiagang 215625China

A series of ferrite/bainite(F/B) multi-phase steels containing different volume fractions of ferrite were *** effect of soft phase(ferrite) content on the work-hardening behavior of the steel was studied by the finite element simulation with V-BCC model and the modified Crussard-Jaoul(C-J) *** is shown that the multi-phase steels have an excellent anti-deformation ability,such as higher stress ratio(R t1.5 /R t0.5),higher uniform elongation and lower yield to tensile strength *** the F/B multi-phase steels,increasing the proportion of ferrite would help to increase the uniform ***,introducing much more fraction of ferrite would not be helpful to improve the stress ratio of multi-phase *** ferrite plastic strain constrained by bainite would be beneficial to increasing the work hardening *** optimum proportion of ferrite will result both higher stress ratio and uniform elongation in multi-phase steel.

关键词：应力应变行为结构钢贝氏体铁素体多相位均匀伸长率加工硬化率性能最佳比例

LHRH/TAT dual peptides-conjugated polymeric vesicles for PTT enhanced chemotherapy to overcome hepatocellular carcinoma

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Chinese Chemical Letters 2020年第12期31卷 3121-3126页

作者： Yu Qin Qing Guo shengjie wu Chenlu Huang Zhiming Zhang Li Zhang Linhua Zhang Dunwan Zhu Tianjin Key Laboratory of Biomedical Materials Key Laboratory of Biomaterials and Nanotechnology for Cancer ImmunotherapyInstitute of Biomedical EngineeringChinese Academy of Medical Sciences&Peking Union Medical CollegeTianjin 300192China

Combination therapy such as photothermal therapy(PTT)enhanced chemotherapy is regarded as a promising strategy for cancer ***,we developed redox-responsive polymeric vesicles based on the amphiphilic triblock copolymer *** avoid the limited therapeutic effect of chemotherapeutic drugs caused by systemic exposures and drug resistance,the redox-sensitive polymeric vesicles were cargoed with two chemotherapeutics:doxorubicin(DOX)and paclitaxel(PTX).Besides,indocyanine green(ICG)was encapsulated,and cell-penetrating peptides and LHRH targeting molecule were modified on the surface of polymeric *** results indicated that the polymeric vesicles can load different kinds of drugs with high drug loading content,trigger drug release in responsive to the reductive environment,realize high cellular uptake via dual peptides and laser irradiation,and achieve higher cytotoxicity via chemo-photothermal combination ***,the redox-responsive LHRH/TAT dual peptides-conjugated PTX/DOX/ICG co-loaded polymeric micelles exhibited great potential in tumor-targeting and chemo-photothermal therapy.

关键词： Redox-responsive Polymeric vesicles Chemotherapy Photothermal therapy Combination therapy

Micelle or polymersome formation by PCL-PEG-PCL copolymers as drug delivery systems

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Chinese Chemical Letters 2017年第9期28卷 1905-1909页

作者： Chunyan Hu Zhuo Chen shengjie wu Yanfeng Han Hai Wang Hongfan Sun Deling Kong Xigang Leng Chun Wang Linhua Zhang Dunwan Zhu Institute of Biomedical Engineering Chinese Academy of Medical Sciences & Peking Union Medical CollegeTianjin Key Laboratory of Biomedical MaterialsTianjin 300192 China School of Biomedical Sciences The University of Queensland Brisbane. QLD 4072. Australia Department of Biomedical Engineering University of MinnesotaMinneapolis. MN 55455. USA

Polye-caprolactone）-b-poly（ethylene glycol）-b-poly（e-caprolactone）（PCL-b-PEG-b-PCL,PCEC） triblock copolymers have been widely investigated in last several ***,by altering the weight ratio of monomers in ring-opening polymerization,a series of PCEC triblock copolymers with varying hydrophobicity were synthesized,which were characterized by FTIR,1 H NMR,GPC and *** PCEC copolymers with different weight ratios of PCL/PEG were dispersed in different aqueous solutions,they could self-assemble and form two distinctive nanoparticular structures：micelles or *** then chose paclitaxel（PTX） as the model drug and encapsulate PTX into PCEC polymeric micelles and *** physicochemical characterizations of the nanoparticles such as morphology,the size and distribution,zeta potential,drug loading content,and encapsulation efficiency were also *** results showed that polymeric micelles or polymersomes from PCEC both displayed narrow size distributions and could achieve high drug loading *** vitro cellular uptake results suggested that Nile Red loaded polymeric micelles or polymersomes displayed more internalization after 24 h incubation than those after 4 h *** findings suggest that polymeric micelles and polymersomes based on PCL-b-PEG-b-PCL copolymers have great potential to effectively delivery hydrophobic drugs.

关键词： Micelle Polymersome Amphiphilic triblock copolymers Drug delivery systems

Mapping the scientific knowledge of glomalin-related soil protein with implications for carbon sequestration

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Ecosystem Health and Sustainability 2022年第1期8卷 324-341页

作者： Shanle Liu Qizhi Wang Lu Qian Binghuang Zhang Xiangwen Chen Hualong Hong shengjie wu Jingchun Liu Chongling Yan Haoliang Lu Ministry of Education Key Laboratory of the Coastal and Wetland EcosystemsXiamen UniversityFujianChina College of the Environment and Ecology Fujian Key Laboratory of Coastal Pollution Prevention and ControlXiamen UniversityFujianChina

Arbuscular mycorrhizal fungi(AMF)derived refractory organic matter,mainly in glomalinrelated soil protein(GRSP),stores globally significant amounts of carbon,attracting wide attention in response to climatic ***,there is no synthesis review has been done so far toreveal global research progresses on GRSP,especially its ecological role forclimate ***,we conducted a bibliometric analysis of the papers on GRSP research from 1998 to 2021,based on the Web of Science(WOS)Core *** collected a total of 634 papers and analyzed the characteristics of publication outputs in various countries and *** addition,keywords analysis was conducted to reveal the main researchdirections and hot trends in the field of *** confirmed that 1)the number of papers published per year has gradually increased since 2010,and increased sharply in 2019;2)the United States was the earliest country to conduct GRSP research,while Chinacurrently has the largest number of publications;3)relevant studies focus on the role from AMF and GRSP in soil health and plant health;4)the contribution of GRSP to soil carbon and its ecological function in mitigatingclimate change are the hotspot of *** benefits of GRSP have become a consensus,however,the nature of glomalin and the mechanisms of GRSP-associated benefits still need to *** an important soil recalcitrant organic carbon,further studies are need to elucidate the land-ocean biogeochemical processes of GRSP and its contribution to global blue carbon.

关键词： Carbon sequestration plant resistance heavy metal soil aggregate