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外部不确定性、数字化赋能与企业全球价值链嵌入——基于“一带一路”沿线国家企业的证据

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当代财经 2024年第4期 127-140页

作者：郭平胡君秦开强南京财经大学金融学院江苏南京210023 云南大学经济学院云南昆明650091

外部不确定性加剧全球价值链收缩,成为“一带一路”区域价值链构建面临的重要问题;深化数字化赋能将帮助企业应对不确定性冲击,稳固企业全球价值链嵌入。采用2.08—2.1 9年世界银行企业调查数据与全球不确定性指数,研究外部不确定性对... 详细信息

外部不确定性加剧全球价值链收缩,成为“一带一路”区域价值链构建面临的重要问题;深化数字化赋能将帮助企业应对不确定性冲击,稳固企业全球价值链嵌入。采用2.08—2.1 9年世界银行企业调查数据与全球不确定性指数,研究外部不确定性对“一带一路”沿线国家企业全球价值链嵌入的影响以及数字化赋能的调节作用。研究发现,外部不确定性显著抑制“一带一路”沿线国家企业全球价值链嵌入决策与嵌入水平;外部不确定性主要通过加大供应链风险、降低生产效率以及阻碍技术创新来抑制企业全球价值链嵌入;异质性分析显示,外部不确定性对小规模企业、高契约密集型行业以及较低制度环境水平国家的全球价值链嵌入的影响更大。企业与国家层面的数字化赋能将有效缓解外部不确定性对“一带一路”沿线国家企业全球价值链嵌入的抑制作用。基于以上研究结论,政府亟须稳定企业外部风险预期,完善供应链风险应对机制,提升企业参与全球价值链分工能力,以数字化赋能促进企业全球价值链韧性提升,加快推动数字基础设施建设与数字贸易制度创新。

关键词：外部不确定性企业全球价值链 “一带一路” 数字化赋能

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基于光学反射层析成像技术的全场前房角测量

生物化学与生物物理进展 2024年第9期51卷 2240-2248页

作者：刘碧旺钟俊平林海纳曾亚光余有平李泓毅韩定安陈金莺佛山大学物理与光电工程学院粤港澳智能微纳光电技术联合实验室佛山528225 佛山大学机电工程与自动化学院佛山528225 暨南大学第一附属医院眼科广州510632

目的闭角型青光眼(ACG)是主要的致盲性眼病之一,研究前房角对闭角型青光眼的诊断具有重要价值。目前,前房角的检查方法包括裂隙灯前房角镜检查、水前房角镜检查、超声生物显微镜(UBM)和眼前节光学相干层析成像(AS-OCT)等。裂隙灯前房角... 详细信息

目的闭角型青光眼(ACG)是主要的致盲性眼病之一,研究前房角对闭角型青光眼的诊断具有重要价值。目前,前房角的检查方法包括裂隙灯前房角镜检查、水前房角镜检查、超声生物显微镜(UBM)和眼前节光学相干层析成像(AS-OCT)等。裂隙灯前房角镜检查和水前房角镜检查便于观察前房角结构,但存在侵入性操作和眼部感染的风险;UBM能精确测量前房角的细微结构,但操作复杂且不适用于经历过外伤或接受过眼科手术的患者;而AS-OCT虽能提供详细的前房角图像,但设备成本较高。本研究旨在探索一种能够低成本实现全场前房角测量的非侵入、无损伤的光学反射层析成像技术(ORT),实现对猪眼三维结构成像和前房角的全场测量。方法搭建了由CMOS相机、远心系统、电机和白光光源组成的光学反射层析成像系统,其空间分辨率为~8.5μm。采集0~2.范围内的反射投影信息,经滤波反射层析算法处理得到三维结构图像,并测量出全场前房角度数。结果本研究使用ORT技术成功采集了猪眼的反射投影数据,重建出其三维结构图像,并测量了前房角度数。重建的三维图像清晰展示了巩膜和虹膜等重要结构,并与实物图的结构一一对应。将ORT与光学相干层析成像系统对猪眼前房角度数的测量结果进行对比,显示两种方法的平均差值为0.51°,均方误差MSE为0.317。结论ORT是一种非侵入、无损伤、成本低和成像分辨率高的技术,能够实现猪眼的三维结构成像和全场前房角测量。该技术为闭角型青光眼的诊断提供了新的视角,对眼科疾病的筛查、诊断和监测具有重要的临床价值。

关键词：闭角型青光眼全场前房角光学反射层析成像

2.G玻璃体切割术治疗糖尿病视网膜病变的疗效分析

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医师在线 2024年第8期14卷 38-40页

作者：陈玉泽张鸿昆明市东川区人民医院眼科昆明654100 昆明医科大学第二附属医院眼科昆明650101

目的比较使用2.G、2.G、2.G玻璃体切割术治疗糖尿病视网膜病变(DR)患者的临床疗效。方法将我院于2.2.年1月~2.2.年1月期间行手术治疗的60例DR患者分为三组,每组2.例。A组实施2. G玻璃体切割术,B组实施2. G玻璃体切割术,C组实施2. G玻璃... 详细信息

目的比较使用2.G、2.G、2.G玻璃体切割术治疗糖尿病视网膜病变(DR)患者的临床疗效。方法将我院于2.2.年1月~2.2.年1月期间行手术治疗的60例DR患者分为三组,每组2.例。A组实施2. G玻璃体切割术,B组实施2. G玻璃体切割术,C组实施2. G玻璃体切割术,对三组眼压、视网膜厚度变化、临床活动度评分(CAS)及DR病变早期治疗研究(ETDRS)评分进行比较。结果治疗前,三组眼压水平比较,差异无统计学意义(P>0.05),治疗后三组眼压水平明显降低(P0.05);治疗后1、3个月,A组的视网膜厚度显著低于B、C组(P0.05);治疗后A组CAS评分显著低于B、C组,差异有统计学意义(P0.05),治疗后三组ETDRS评分明显下降(P0.05)。结论2.G玻璃体切割术应用于DR患者治疗中效果较好,能够降低眼压波动,改善视力水平与眼部功能。

关键词： 2.G 2.G 2.G 玻璃体切割术微创糖尿病视网膜病变

Characterization and in-situ formation mechanism of tungsten carbide reinforced Fe-based alloy coating by plasma cladding

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International Journal of Minerals,Metallurgy and Materials 2018年第4期25卷 439-443页

作者： Mi-qi Wang ze-hua Zhou Lin-tao Wu Ying Ding ze-hua Wang College of mechanics and materials Hohai University

The precursor carbonization method was first applied to prepare W–C compound powder to perform the in-situ synthesis of the WC phase in a Fe-based alloy coating. The in-situ formation mechanism during the cladding process is discussed in detail. The results reveal that fine and obtuse WC particles were successfully generated and distributed in Fe-based alloy coating via Fe/W–C compound powders. The WC particles were either surrounded by or were semi-enclosed in blocky M7C3 carbides. Moreover, net-like structures were confirmed as mixtures of M2.C6 and α-Fe; these structures were transformed from M7C3. The coarse herringbone M6C carbides did not only derive from the decomposition of M7C3 but also partly originated from the chemical reaction at the α-Fe/M2.C6 interface. During the cladding process, the phase evolution of the precipitated carbides was WC → M7C3 → M2.C6 ＋ M6C.

关键词： precursor carbonization tungsten carbide (WC) microstructure in-situ formation mechanism phase evolution

Investigation on Vibrational Spectra and Structures of 4-Mercaptopyridine Monomer and Its Dihydrate

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Chemical Research in Chinese Universities 2006年第1期22卷 90-93页

作者： CHENG Jian-bo 1,2., XUE Wei-qing 1 , ZHAO Bing 1** , ZHANG Gang 3 and GONG Bao-an 2.1. Key Laboratory for Supramolecular Structure and Material of Ministry of Education, Jilin University, Changchun 130012. P. R. China 2. Science and Engineering College of Chemistry and Biology, Yantai University, Yantai 2.4005, P. R. China 3. State Key Laboratory of Theoretical and Computational Chemistry, Jilin University, Changchun 13002., P. R. China [a]Key Laboratory for Supramolecular Structure and Material of Ministry of Education Jiln University Changchun 130012 P. R. China[b]Science and Engineering College of Chemistry and Biology Yantai University Yantai 264005 P. R. China[c]State Key Laboratory of Theoretical and Computational Chemistry Jiln University Changchun 130023 P. R. China

The optimized molecular structures and vibrational frequencies of 4-mercaptopyridine(4MPY) monomer and its dihydrate were studied by means of the density functional theory(DFT), viz. B3LYP method with the 6-311++G(d,p) basis set. On the basis of the calculations, the assignments of the vibrational spectra of the monomer and the dihydrate were performed, and so were investigated the changes in the structure and the vibrational spectrum of the dihydrate as well as the intermolecular force resulting in the formation of the dihydrate. The calculated results show that each of the water molecule planes is vertical to the pyridine ring plane in the dihydrate that is formed via the H-bonds between 4MPY and water molecules. Furthermore, the structure and the vibrational spectrum of 4MPY can be consi- derably affected by the water molecules.

关键词： 4MPY Dihydrate Vibrational spectra DFT Molecular structure

含伏诺拉生四联疗法根除幽门螺杆菌感染的疗效

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中国新药与临床杂志 2024年第3期43卷 213-216页

作者：钟万锷曹萍宁波市第六医院消化内科浙江宁波315040

目的观察含伏诺拉生的四联14 d疗法治疗幽门螺杆菌(Hp)感染的效果。方法回顾性分析12.例Hp阳性患者,将其按治疗方案分为治疗组和对照组,各60例。治疗组口服伏诺拉生2. mg+枸橼酸铋钾2.0 mg+阿莫西林1000 mg+呋喃唑酮100 mg;对照组口服... 详细信息

目的观察含伏诺拉生的四联14 d疗法治疗幽门螺杆菌(Hp)感染的效果。方法回顾性分析12.例Hp阳性患者,将其按治疗方案分为治疗组和对照组,各60例。治疗组口服伏诺拉生2. mg+枸橼酸铋钾2.0 mg+阿莫西林1000 mg+呋喃唑酮100 mg;对照组口服奥美拉唑2. mg+阿莫西林1000 mg+枸橼酸铋钾2.0 mg+呋喃唑酮100 mg,均每日2.,共14 d。患者均在疗程结束后4~6周内行^(14)C-尿素呼气试验,分别观察2.Hp根除情况及不良反应的发生情况。结果纳入的12.例患者中,男性57例,女性63例,年龄2.~69岁,平均(37.9±5.4)岁,Hp根除率治疗组高于对照组(97%vs.80%,P2.不良反应发生率无显著差异(P>0.05)。结论含伏诺拉生的四联14 d疗法治疗Hp感染是一种安全高效的根除Hp治疗方法,可作为一线及二线治疗方案。

关键词：伏诺拉生四联疗法幽门螺杆菌

Production of porcine cloned transgenic embryos expressing green fluorescent protein by somatic cell nuclear transfer

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Science China(Life Sciences) 2006年第2期49卷 164-171页

作者： ZHANG Yunhai1, PAN Dengke1,2. SUN Xiuzhu1, SUN Guojie1, WANG Xiaobo1, LIU Xiaohui1, LI Yan1, DAI Yunping1 & LI Ning1 1. State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing 100094, China 2. College of Animal Science and Technology, China Agricultural University, Beijing 100094, China State Key Laboratory for Agrobiotechnology China Agricultural University Beijing 100094 China College of Animal Science Technology China Agricultural University Beijing 100094 China

In the present study, nuclear transferred embryos (NTEs) were reconstructed by using pig fetal fibroblasts as donors; in vitro matured oocytes as recipients. The effects of G418 selection on donor cells, duration of IVM of prepubertal gilt oocytes; oxygen tension in IVM of oocytes were investigated. The results were as follows: (i) When G418 selected cells expressing GFP were used as donors, the cleavage rate of NTEs decreased drastically in comparison to NTEs derived from donors without antibiotic selection (47.5% vs. 71.6%, p>0.05). For the blastocyst rate, no significant difference was observed between two groups (10% vs. 10.4%, p2.h (83.6% vs. 96.7%, p>0.05). However, no statistical difference was observed between NTEs derived from oocytes of 36 h IVM group; NTEs from oocytes of 42.h IVM group in the rates of cleavage (59.3% vs. 73.6%, p2., p2. tension; NTEs derived from oocytes matured under higher oxygen tension (2.% O2. in cleavage rate (70.6% vs. 67.1%, p2.3%, p2.h, while no significant differences were observed for developmental potential of transgenic embryos. Thus IVM 42.h is the better choice in order to obtain maximum number of MII oocytes as recipients. (iii) Lower oxygen tension; higher oxygen tension in IVM have no significant effect on development of cloned embryos.

关键词： transgenic cloning, GFP, Pig, early development.

Rb-Sr isochron ages and significance of bimodal volcanic association in Baimianshi uranium ore-field, South China

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Chinese Science Bulletin 1999年第S2期44卷 3-4页

作者： CHEN Peirong~1, WANG Yinxi~2. NI Qisheng~1, KONG Xinggong~2.and ZHANG Bangtong~2.1. State Key Laboratory of Mineral Deposits, Department of Earth Sciences, Nanjing University, Nanjing 2.0093, China 2. Center of Modern Analysis, Nanjing University, Nanjing 2.0093, China State Key Laboratory of Mineral Deposits Department of Earth Sciences Nanjing University Nanjing 210093 China Center of Modern Analysis Nanjing University Nanjing 210093 China

1 Geologic background THE volcanic U-deposits are generally associated with felsic to intermediate volcanic rock and their sedimentary derivatives. However, uranium mineralization has been found to be spatially associated with thebasalt of bimodal volcanic associations in Baimianshi uranium ore field. Baimianshi uranium ore-field islocated in Baimianshi volcanic-sedimentary basin of south Jiangxi Province. The cover rocks of the basinconsist of a suite of bimodal volcanic-sedimentary sequences. Its basement rocks are two-mica granites ofBaimianshi rock body. The basalt of cover rocks is interbedded with arkoses in lower sequence, and rhyolite or rhyolitic tuff in upper sequence. Uranium minerals mainly occur as disseminations in the

关键词： Rb-Sr isochron ages bimodal volcanic rocks uranium ore-field south China.

长期玉米秸秆还田对褐土细菌群落和酶活性的影响

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植物营养与肥料学报 2024年第5期30卷 996-1007页

作者：赵宇航殷浩凯解文艳刘志平周怀平杨振兴山西农业大学资源环境学院山西太原030031

【目的】探讨不同秸秆还田模式对褐土农田养分的影响,解析土壤胞外酶活性和菌群功能的变化特征,为高效提升褐土农田土壤肥力提供理论依据。【方法】本研究基于1992.2.2.年位于山西寿阳的长期定位试验,包括4种玉米秸秆还田方式处理:秸... 详细信息

【目的】探讨不同秸秆还田模式对褐土农田养分的影响,解析土壤胞外酶活性和菌群功能的变化特征,为高效提升褐土农田土壤肥力提供理论依据。【方法】本研究基于1992.2.2.年位于山西寿阳的长期定位试验,包括4种玉米秸秆还田方式处理:秸秆不还田(CK)、秸秆过腹还田(CM)、秸秆粉碎直接还田(SC)和秸秆覆盖还田(SM)。取样分析土壤养分含量和胞外酶活性;利用高通量测序技术、FAPROTAX功能预测和生态网络方法,分析细菌群落结构,预测菌群功能。【结果】1)长期不同秸秆还田方式(SM、SC和CM)均可显著提高土壤肥力、玉米产量和胞外酶活性。与CK相比,3个秸秆还田处理的土壤有机碳(SOC)、全氮(TN)、全磷(TP)、全钾(TK)、碱解氮(AN)、有效磷(AP)和速效钾(AK)含量分别提升了17.0%~42.9%、3.0%~50.0%、2.3%~2..9%、4.4%~11.5%、11.2.~71.0%、14.1%~32..8%、17.1%~153.6%;土壤葡萄糖苷酶(β-GC)、纤维二糖水解酶(CBH)和脱氢酶(DHA)含量分别提升了35.6%~190.7%、41.9%~58.6%和2..8%~773.8%;玉米累计产量提高了6.4%~2..0%。2.SM、SC和CM处理提高了土壤细菌Chao 1指数、Peilou’s evenness指数和Shannon指数,提高了拟杆菌门、变形菌门、厚壁菌门和放线菌门的相对丰度,降低绿弯菌门和酸杆菌门的相对丰度。土壤pH和土壤有机碳是影响细菌群落组成的重要影响因素。3)网络分析结果表明,长期秸秆还田处理指示种归属于不同模块,与土壤养分含量和酶活性呈显著相关关系,其中CM处理中富集的Chryseolinea通过强烈共生关系形成特定功能微生物集群。4)基于FAPROTAX的功能预测,发现长期不同秸秆还田提高了土壤菌群对有机物质的分解潜力和氮组分转化潜力。【结论】长期不同秸秆还田均显著提升土壤肥力和玉米产量,增加土壤酶活性,提高细菌多样性,改变细菌群落结构和组成,提高土壤碳氮循环功能,从而促进褐土形成适合作物和细菌生长的环境。

关键词：秸秆还田方式细菌群落酶活性土壤养分高通量测序网络分析