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Effect of rare earth on primary carbides in H13 die steel and their addition method:a review

Journal of Iron and Steel Research(International) 2024年第3期31卷 531-551页

作者： Jing-feng wang Lin-zhu wang Chao-yi Chen Xiang wang Fei Zhao School of Materials and Metallurgy Guizhou UniversityGuiyang 550025GuizhouChina Zhengzhou Railway Vocational and Technical College Zhengzhou 450000HenanChina Guizhou Provincial University Key Laboratory of High Performance Battery Materials Guizhou UniversityGuiyang 550025GuizhouChina Shougang Guiyang Special Steel Co. Guiyang 550005GuizhouChina

Larger-sized primary carbides lead to stress concentration during the application of H13 hot-work die steel,resulting in microcracks and fatigue failure.Rare earth was usually added to modify the carbides and inclusions.The existing literature is reviewed on the effect of rare earth on primary carbides in H13 steel.A comprehensive review on the effect of rare earth on the characteristics of primary carbides,i.e.,number,size,morphology,and thermal stability in H13 steel,was done.The precipitation mechanism and nucleation of primary carbides with rare earth were summarized.The position and form of rare earth in steel and their effects on alloying elements segregation were reviewed.The addition techniques of rare earth in H13 steel were compared,and the prospects for other uncommon rare earth and emerging technology were present.Based on the current references,it can be known that adding rare earth facilitated refined and dispersed primary carbides.The size of primary carbides would be reduced,and their morphology would be improved because the rare earth inclusions formed in H13 steel can act as nucleation cores forγ-Fe orδ-Fe,refining the dendritic structure.Besides,the number of primary carbides at grain boundaries would be significantly reduced.However,rare earth had little impact on thermal stability.The nucleation of primary carbides tended to be inhibited due to the modification of inclusions by rare earth which were likely to be nucleation cores for primary carbides.Rare earth had been reported to affect the mechanism and process of primary carbide precipitation.Additionally,the addition of rare earth can inhibit the segregation of alloying elements and carbon diffusion by calculation.Thus,laboratory experiments and theoretical calcu-lations need to be conducted to study the states and evolution of rare earth steels.

关键词： Rare earth H13 die steel Primary carbide Nucleation dendritic structure

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Serum 25-hydroxyvitamin D, genetic susceptibility, and the risk of incident type 2 diabetes: A prospective cohort in East China

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中华医学杂志(英文版) 2024年第8期137卷 972-979页

作者： Sun ying Zhang Haojie wang Bin wang Yuying Chen Chi Chen yi Lu yingli wang Ningjian West China Hospital Sichuan University Chengdu Sichuan 610041 department of Endocrinology Shuguang Hospital Affiliated to Shanghai University of Traditional Chinese Medicine Shanghai 201203 Institute and department of Endocrinology and Metabolism Shanghai Ninth People’s Hospital Shanghai JiaoTong University School of Medicine Shanghai 200011 China department of Endocrinology and Metabolism and department of Guideline and Rapid Recommendation Cochrane China Center MAGIC China Center Chinese Evidence-Based Medicine Center

Background: The serum vitamin D level varies widely by population, and studies have linked vitamin D levels with the risk of type 2 diabetes mellitus (T2DM). However, the relationship is inconsistent and the impact of vitamin D on T2DM among East Chinese adults is unclear. The study aimed to investigate the association between serum 25-hydroxyvitamin D (25[OH]D) levels and the risk of T2DM and evaluated whether the association is modified by genetic predisposition.Methods: In the Survey on Prevalence in East China for Metabolic Diseases and Risk Factors (SPECT-China) cohort, 1862 participants free of T2DM at baseline were included. A weighted genetic risk score was calculated with 28 variants associated with T2DM. Hierarchical logistic models were used to examine the association of serum 25(OH)D and genetic risk with T2DM.Results: After a 5-year follow-up, 132 cases of T2DM were documented. We observed no significant association between quartiles of serum 25(OH)D and T2DM risk after multivariable adjustment (χ2 = 0.571,Pfor trend = 0.426). Compared to those in the lowest quartile of 25(OH)D, the odds ratios (ORs) (95% confidence interval [CI]) for participants with increased quartiles were 1.29 (0.74-2.25), 1.35 (0.77-2.36), and 1.27 (0.72-2.24), respectively. We observed a positive association of glycated hemoglobin (HbA1c) with 25(OH)D at baseline (β = 1.752,P = 0.001) and after follow-up (β = 1.385,P = 0.003), and a negative association of ln conversion homeostasis model assessment (HOMA)-β with 25(OH)D at baseline (β = -0.982,P = 0.021). There was no significant interaction between 25(OH)D and diabetes genetic predisposition on the risk of T2DM (χ2 = 2.710,Pfor interaction = 0.100). The lowest OR (95% CI) of T2DM was among participants with low genetic risk and the highest quartile of 25(OH)D (0.17 [0.05–0.62]).Conclusion: Serum 25(OH)D may be irrelevant to the risk of incident T2DM among East Chinese adults regardless of genetic predisposition.

关键词： Vitamin D Diabetes mellitus, Type 2 Genetic predisposition to disease Prospective cohort Glycated hemoglobin SPECT-China

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Acyclic Edge Coloring of 1-planar Graphs without 4-cycles

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Acta Mathematicae Applicatae Sinica 2024年第1期40卷 35-44页

作者： Wei-fan wang yi-qiao wang Wan-shun Yang department of Mathematics Zhejiang Normal UniversityJinhua321004China School of Management Beijing University of Chinese MedicineBeijing100029China School of Mathematics and Information Science Weifang UniversityWeifang261061China

An acyclic edge coloring of a graph G is a proper edge coloring such that there are no bichromatic cycles in G.The acyclic chromatic index χ'α(G) of G is the smallest k such that G has an acyclic edge coloring using k colors.It was conjectured that every simple graph G with maximum degree Δ has χ'_α(G) ≤Δ+2.A1-planar graph is a graph that can be drawn in the plane so that each edge is crossed by at most one other edge.In this paper,we show that every 1-planar graph G without 4-cycles has χ'_α(G)≤Δ+22.

关键词： 1-planar graph acyclic edge coloring acyclic chromatic index

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Treatment of multisystem inflammatory syndrome in children

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World Journal of Pediatrics 2024年第4期20卷 325-339页

作者： Tong Tong yi-Hua Jin Min wang Fang-Qi Gong department of Cardiology Children's HospitalZhejiang University School of MedicineNational Clinical Research Center for Child HealthNo.3333 Binsheng RoadHangzhou 310052China

Background Multisystem inflammatory syndrome in children(MIS-C),a relatively uncommon but severe pediatric complication,is associated with coronavirus disease 2019(COVID-19).A variety of treatment approaches,including intravenous immunoglobulins(IVIGs),glucocorticoids(GCs)and biologic agents,such as anakinra and infliximab,have been described for the management of COVID-19-related MIS-C.Anticoagulant therapy is also important.However,a well-developed treatment system has not been established,and many issues remain controversial.Several recently published articles related to the treatment of MIS-C have been released.Hence,in this review,we identified relevant articles published recently and summarized the treatment of MIS-C more comprehensively and systematically.Data sources We reviewed the literature on the treatment of MIS-C through 20 September 2023.The PubMed/Medline,Web of Science,EMBASE,and Cochrane Library databases were searched with the combination of the terms"multisystem inflammatory syndrome","MIS-C","PIMS-TS","therapy","treatment","drug","IVIG","GCs","intravenous immunoglobulin","corticosteroids","biological agent",and"aspirin".Results The severity of MIS-C varies,and different treatment schemes should be used according to the specific condition.Ongoing research and data collection are vital to better understand the pathophysiology and optimal management of MIS-C.Conclusions MIS-Cis a disease involving multiple systems and has great heterogeneity.With the accumulation of additional experience,we have garnered fresh insights into its treatment strategies.However,there remains a critical need for greater standardization in treatment protocols,alongside the pressing necessity for more robust and meticulously conducted studies to deepen our understanding of these protocols.

关键词： Coronavirus disease 2019-Corticosteroids Intravenous immunoglobulin Multisystem inflammatory syndrome in children-Treatment

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China stroke surveillance report 2021

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Military Medical Research 2024年第3期11卷 374-399页

作者： Wen-Jun Tu Long-de wang 无 department of Neurosurgery Beijing Tiantan HospitalCapital Medical UniversityBeijing 100070China School of Public Health Peking UniversityBeijing 100191China Special Writing Group of China Stroke Surveillance Report

Since 2015,stroke has become the leading cause of death and disability in China,posing a significant threat to the health of its citizens as a major chronic non-communicable disease.According to the China Stroke High-risk Population Screening and Intervention Program,an estimated 17.8 million[95%confidence interval(CI)17.6–18.0million]adults in China had experienced a stroke in 2020,with 3.4 million(95%CI 3.3–3.5 million)experiencing their first-ever stroke and another 2.3 million(95%CI 2.2–2.4 million)dying as a result.Additionally,approximately 12.5%(95%CI 12.4%–12.5%)of stroke survivors were left disabled,as defined by a modified Rankin Scale score greater than 1,equating to 2.2 million(95%CI 2.1–2.2 million)stroke-related disabilities in 2020.As the population ages and the prevalence of risk factors like diabetes,hypertension,and hyperlipidemia continues to rise and remains poorly controlled,the burden of stroke in China is also increasing.A large national epidemiological survey initiated by the China Hypertension League in 2017 showed that the prevalence of hypertension was 24.7%;the awareness,treatment,and control rates in hypertensive patients were:60.1%,42.5%,and 25.4%,respectively.A nationally representative sample of the Chinese mainland population showed that the weighted prevalence of total diabetes diagnosed by the American Diabetes Association criteria was 12.8%,suggesting there are 120 million adults with diabetes in China,and the awareness,treatment,and control rates in diabetic patients were:43.3%,49.0%,and 49.4%,respectively.The“Sixth National Health Service Statistical Survey Report in 2018”showed that the proportion of the obese population in China was 37.4%,an increase of 7.2 points from 2013.Data from 1599 hospitals in the Hospital Quality Monitoring System and Bigdata Observatory Platform for Stroke of China(BOSC)showed that a total of 3,418,432 stroke cases[mean age±standard error(SE)was(65.700±0.006)years,and 59.1%were male]were admitted during 2020.Of those,over 80.0%(81.9%)were ischemic

关键词： Stroke Epidemiological characteristics Treatment Prognosis China

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Vanadium(V) Complexes Containing Unsymmetrical N-Heterocyclic Carbene Ligands: Highly Efficient Synthesis and Catalytic Behavior towards Ethylene/Propylene Copolymerization

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Chinese Journal of Polymer Science 2024年第1期42卷 32-41,I0006页

作者： yi-Cong wang Hui Zhat Pei-yi Cheng Shu Zhang Xiang-Wei Liu yi-Xian Wu State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical TechnologyBejing 100029China

The highly efficient method has been developed for the synthesis of NHC·VOCl_(3) containing symmetrical or unsymmetrical Nheterocyclic carbene(NHC) ligands by the transmetallation reaction of NHC·AgCl with VOCl_(3).The total isolated yield of VOCl_(3)[1,3-(2,4,6-Me_(3)C_(6)H_(2))_(2)(NCH=)_(2)C:](V4') reached 86% by transmetallation reaction,which is much higher than that(48%) by direct coordination method.This methodology has also been used to synthesize the novel vanadium complexes containing unsymmetrical NHC ligands of VOCl_(3)[PhCH_(2)NCH=CHNR)C:](V5',R=2,4,6-Me_(3)C_(6)H_(2);V6',R=2,4-Me_(2)-6-Ph-C_(6)H_(2);V7',R=2,6-^(i)Pr_(2)-C_(6)H_(3)) with high yield,which could not be obtained by direct coordination method.The catalytic activity and copolymerization ability would be improved by introducing unsymmetrical NHC ligands due to their less steric bulky effect.The vanadium complex V5' containing unsymmetrical NHC ligand exhibits higher catalytic activity(3.7×10^(5)g_(copolymer)·mol^(-1) of V·h^(-1)) than that of V4' containing symmetrical NHC ligand.Moreover,the higher propylene incorporation ratio(45.6 mol%) in the copolymers of ethylene with propylene could be obtained by using V5' than that(39.9%) by using V4'.The results would provide a highly efficient strategy for the synthesis of early transition metal complexes containing versitile NHC ligands,affording the catalyst with both high catalytic activity and copolymerization ability for the synthesis of high performance polyolefin elastomers.

关键词： Vanadium complex N-heterocyclic carbene ligand Transmetallation reaction Copolymerization of ethylene with propylene

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Can the integration between urban and rural areas be realized?A new theoretical analytical framework

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Journal of Geographical Sciences 2024年第1期34卷 3-24页

作者： wang yi LU Yuqi ZHU yingming Research Base of Jiangsu Industrial Cluster School of Economics and ManagementNanjing University of Science and TechnologyNanjing 210094China School of Geography Nanjing Normal UniversityNanjing 210023China

Urban-rural integration is an advanced form resulting from the future evolution of urban-rural relationships.Nevertheless,little research has explored whether urban and rural areas can move from dual segmentation to integrated development from a theoretical or empirical perspective.Based on the research framework of welfare economics,which offers an appealing paradigm to frame the underlying game between cities and villages,this study clarifies the ideal state of urban-rural integration.It then proposes a series of basic assumptions,and constructs a corresponding objective function and its constraints.Moreover,it assesses the possibility of seeing the transmutation from division to integration between urban and rural areas with continuous socio-economic development.The authors argue that the ideal state of urban-rural integration should be a Pareto-driven optimal allocation of urban-rural resources and outputs,and the maximization of social welfare in the entire region.Based on a systematic demonstration using mathematical models,the study proposes that urban and rural areas can enter this ideal integrated development pattern when certain parameter conditions are met.In general,this study demonstrates the theoretical logic and scientific foundations of urban-rural integration,enriches theoretical studies about urban-rural relationships,and provides basic theoretical support for large developing countries to build a coordinated and orderly urban-rural community with a shared future.

关键词： urban-rural integration development ideal state parameter conditions welfare economics theoretical framework

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Dry environment on the expression of lacrimal gland S100A9,Anxa1,and Clu in rats via proteomics

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International Journal of Ophthalmology(English edition) 2024年第3期17卷 435-443页

作者： yi-Lin Sun A-Yuan Cui Li-Xin wang wang-wang Zhang Hong Shi College of Traditional Chinese Medicine Xinjiang Medical UniversityUrumqi 830011Xinjiang Uygur Autonomous RegionChina Research on High Incidence of Diseases in Xinjiang Region Key Laboratory of the Ministry of Education(Xinjiang Medical University)Urumqi 830011Xinjiang Uygur Autonomous RegionChina

●AIM:To investigate the underlying mechanism of dry environment(autumn dryness)affecting the lacrimal glands in rats.●METHODS:Twenty Sprague-Dawley rats were randomly divided into two groups.The rats were fed in specific pathogen free environment as the control group(n=10),and the rats fed in dry environment as the dryness group(n=10).After 24d,lacrimal glands were collected from the rats.The tissues morphology was observed by hematoxylineosin(HE)staining.Tandem mass tags(TMT)quantitative proteomics analysis technology was used to screen the differential expressed proteins of lacrimal glands between the two groups,then bioinformatics analysis was performed.Further,the immunohistochemical(IHC)method was used to verify the target proteins.●RESULTS:In dryness group,the lacrimal glands lobule atrophied,the glandular cavities enlarged,the sparse nuclear distribution and scattered inflammatory infiltration between the acinus were observed.The proteomics exhibited that a total of 195 up-regulated and 236 downregulated differential expressed proteins screened from the lacrimal glands of rats.It was indicated that the biological processes(BP)of differential expressed proteins mainly included cell processes and single BP.The cellular compositions of differential expressed proteins mainly located in cells,organelles.The molecular functions of differential expressed proteins mainly included binding,catalytic activity.Moreover,the Kyoto Encyclopedia of Genes and Genomes(KEGG)pathway analysis showed that the differential expressed proteins mainly involved lysosome,complement and coagulation cascade,and ribosome pathway.The IHC result verified that the up-regulated expression proteins of Protein S100A9(S100A9),Annexin A1(Anxa1),and Clusterin(Clu)in lacrimal glands of rats in dryness group were higher than control group.●CONCLUSION:The up-regulated expression proteins of S100A9,Anxa1,and Clu may be the potential mechanisms of dry eye symptoms caused by dry environment.This study provides clues of dry environments causing eye-rel

关键词： dry eye lacrimal gland S100A9 Clu Anxa1 environment rats

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Electrochemical Analysis of Single Glucose Oxidase with a Nanopipette

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Chemical Research in Chinese Universities 2024年第2期40卷 272-278页

作者： wang Yongyong MA Hui LONG yi-Tao yiNG yi-Lun School of Chemistry and Chemical Engineering Molecular Sensing and Imaging Center(MSIC)Nanjing UniversityNanjing210023P.R.China

Nanopore-based electrochemical technique is a promising tool for detecting single proteins.However,detecting single proteins using a nanopipette in their native state without labeling is challenging due to the rapid translocation,which results in an inefficient signal identification.In our study,we finely tuned the driving force equilibrium between electrophoretic force(EPF)and electroosmotic flow(EOF)inside the nanopipette for efficient sensing of single glucose oxidase(GOD)molecules.The duration time of GOD within the nanopipette is extended to about 4 ms.This strategy provided clear ionic current signals with a signal-to-noise ratio of 3.3.As EPF increased in the direction opposite to the motion of GOD,we observed a nonlinear growth in GOD’s duration time.This extended the duration to about 4.4 times longer at−1000 mV compared to at−800 mV.Hence,nanopore-based electrochemical sensing could be used for single GOD molecule analysis as an ultrasensitive method.

关键词： Nanopore Single-molecule analysis Glucose oxidase Electrophoretic force Electroosmotic flow

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A dynamic exploratory hybrid modelling framework for simulating complex and uncertain system

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Journal of Safety Science and Resilience 2024年第2期5卷 167-178页

作者： Gangqiao wang Han Xing Yongqiang Chen yi Liu Institute of Big Data Inteligent Management and decision-making College of ManagementShenzhen UniversityShenzhen 518060China School of Safety Science Tsinghua UniversityBejing 100084China department of Mechanics and Engineering Science College of EngineeringPeking UniversityBejing 100871China

Complex disaster systems involve various components and mechanisms that could interact in complex ways and change over time,leading to significant deep uncertainty.Due to deep uncertainty,decision-makers have severe inadequacy of knowledge and often encounter unpredictable surprises that may emerge in the future,thus making it difficult to specify appropriate models and parameters to describe the system of interest.In this paper,we propose a dynamic exploratory hybrid modeling framework that fits data,models,and computational ex-periments together to simulate complex systems with deep uncertainty.In the framework,one needs to develop multiple plausible models from a hybrid modeling perspective and perform enormous computational experi-ments to explore the diversity of future scenarios.Real-time data is then incorporated into diverse forecasts to dynamically adjust the simulation system.This ultimately enables an ongoing modeling and analysis process in which deep uncertainty would be gradually mitigated.Our approach has been applied to a human-involved car-following system simulation under complex traffic conditions.The results show that the proposed approach can improve the prediction accuracy while enhancing the sensitivity of the simulation system to uncertain changes in the system of interest.

关键词： Disaster modeling and analysis deepuncertainty Hybrid modeling Adaptivesimulation

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