检索结果-南通市图书馆

Modified-starch Consolidation of Alumina Ceramics

在线全文

学校读者我要写书评

暂无评论

Journal of Wuhan University of Technology(Materials Science) 2008年第4期23卷 558-561页

作者： JU Chenhui wang Yanmin ye jiandong HUANG Yun Key Laboratory of Specially Functional Materials of Ministry of Education and School of Materials Science and Engineering South China University of Technology Guangzhou 510641 China School of Light Industry and Food Science South China University of Technology Guangzhou 510641 China

The alumina ceramics with the homogeneous microstructure and the higher density were fabricated via the modified-starch consolidation process by 1.0 wt% of a modified starch as a consolidator/ binder. The swelling behavior of the modified oxidized tapioca starch was analyzed by optical microscope, and two other corn starches （common corn starch and high amylose corn starch） were also analyzed for comparison. The modified starch used as a binder for the consolidation swelled at about 55 ℃, began to gelatinize at 65 ℃ and then was completely gelatinized at 75 ℃. But the corn starches could not be completely gelatinized even at 80 ℃ for 1 h. The high-strength green bodies （10.6 MPa） with the complex shapes were produced. The green bodies were sintered without any binder burnout procedure at 1 700 ℃ and a relative density of 95.3% was obtained for the sintered bodies, which is similar to that of the sintered sample formed by conventional slip casting. In addition, the effect of temperature on the apparent viscosity of the starch/alumina slurry in the process was investigated, and the corresponding mechanism for the starch consolidation was discussed.

关键词： oxidized starch gelation alumina ceramic starch consolidation

Critical adhesion areas of cells on micro-nanopatterns

在线全文

学校读者我要写书评

暂无评论

Nano Research 2022年第2期15卷 1623-1635页

作者： Shuang Zheng Qiong Liu Junhao He Xinlei wang Kai ye Xuan wang Ce Yan Peng Liu jiandong Ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China Navy Characteristic Medical Center the Second Military Medical UniversityShanghai 200433China College of Bioengineering Chongqing UniversityChongqing 400044China

Cell adhesion to extracellular matrices(ECM)is critical to physiological and pathological processes as well as biomedical and biotechnological *** has been known that a cell can adhere on an adhesive microisland only over a critical *** no publication has concerned critical adhesion areas of cells on microislands with nanoarray ***,we fabricated a series of micro-nanopatterns with different microisland sizes and arginine-glycine-aspartate(RGD)nanospacings on a nonfouling poly(ethylene glycol)*** reproducing that nanospacing of RGD,a ligand of its receptor integrin(a membrane protein),significantly influences specific cell adhesion on bioactive nanoarrays,we confirmed that the concept of critical adhesion area originally suggested in studies of cells on micropatterns was justified also on the micro-nanopatterns,yet the latter exhibited more characteristic behaviors of cell *** found increased critical adhesion areas of human mesenchymal stem cells(hMSCs)on nanoarrayed microislands with increased RGD ***,the numbers of nanodots with respect to the critical adhesion areas were not a constant.A unified interpretation was then put forward after combining nonspecific background adhesion and specific cell *** further carried out the asymptotic analysis of a series of micro-nanopatterned surfaces to obtain the effective RGD nanospacing on unpatterned free surfaces with densely grafted RGD,which could be estimated nonzero but has never been revealed previously without the assistance of the micro-nanopatterning techniques and the corresponding analysis.

关键词： biomaterial surface patterning cell adhesion arginine-glycine-aspartate(RGD)nanospacing poly(ethylene glycol) critical adhesion area

Use of Otolith Shape for the Identification of Trumpeter Sillago (Sillago maculata) and Silver Sillago(Sillago sihama)

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Ocean University of China 2010年第3期9卷 286-290页

作者： wang yingjun ye Zhenjiang LIU Qun College of Fisheries Ocean University of China Qingdao 266003 P. R. China

Otolith shape is species-specific in *** this study,161 samples of Trumpeter sillago Sillago maculata and 164 of Silver sillago Sillago sihama were collected from Beibu Gulf in July *** main objective of this study was to use morphological variables and Fourier harmonics to describe otolith characteristics and use discriminant analyses to separate the two *** were measured by traditional one and two dimensional measures(otolith length,width,diameters,area,perimeter,rectangularity and circularity),as well as by Fourier analysis to capture the finer regions of the *** of covariance(ANCOVA) showed that there was significant correlation between morphological variables(diameter,perimeter,otolith length,otolith width,otolith area,density,harmonics 3,harmonics 4,harmonics 5,harmonics 13,harmonics 15,and harmonics 16) and body *** minimize size effects on the morphological variables between species,only fish with a body length between 90 and 140 mm were included in the data analysis and the variables which had significant relation with body length were transformed using the *** result showed that the accuracy of discriminant analysis was 97.8% and 100% for Trumpeter sillago and Silver sillago,*** high accuracy indicated that otolith shape was described accurately by morphological variables and Fourier harmonics,and discriminant analysis was an effective way to identify and separate the two species.

关键词： Sillago maculate Sillago sihama Otolith shape analysis Fourier analysis identification

钙磷摩尔比对新型PCCP+DCPA体系骨水泥性能的影响(英文)

在线全文

学校读者我要写书评

暂无评论

硅酸盐学报 2007年第12期35卷 1582-1586页

作者：王秀鹏叶建东王迎军华南理工大学特种功能材料教育部重点实验室广州540641 华南理工大学材料学院

用化学沉淀法合成了不同钙/磷摩尔比并含碳酸根的部分结晶磷酸钙(partially crystallized calcium phosphates, PCCP),用 PCCP 和无水磷酸氢钙(dicalcium phosphate anhydrous, DCPA)配制了 PCCP+DCPA 体系磷酸钙骨水泥,用去离子水作为骨水泥的固化液。通过相组成的 X 射线衍射分析、扫描电子显微镜观察、孔隙率和抗压强度测定,研究了钙磷摩尔比[n(Ca)/n(P)]对 PCCP+DCPA 磷酸钙骨水泥性能的影响。结果表明:随着部分结晶磷酸钙中 n(Ca)/n(P)的提高,磷酸钙骨水泥试件的抗压强度明显下降,但磷酸钙骨水泥水化产物羟基磷灰石的结晶度提高,固化体中大于 100 nm 的孔隙增多、固化体的孔隙率增大,可见,n(Ca)/n(P)对磷酸钙骨水泥的性能有重要影响,在制备磷酸钙骨水泥时应选择适当的 n(Ca)/n(P)。

关键词：骨水泥磷酸钙孔隙率结晶程度抗压强度

具有定向孔隙结构的大孔磷酸钙骨水泥支架的制备与表征(英文)

在线全文

学校读者我要写书评

暂无评论

硅酸盐学报 2007年第12期35卷 1577-1581页

作者：漆小鹏叶建东王秀鹏王迎军华南理工大学材料科学与工程学院特种功能材料教育部重点实验室广州510641

利用冷冻塑形法制备了具有定向孔隙结构的大孔磷酸钙骨水泥支架。利用扫描电镜(scanning electron microscope,SEM)和X射线衍射(X-ray diffraction,XRD)对材料的孔隙结构和物相进行了研究。SEM照片显示:多孔磷酸钙骨水泥具有与冰晶生长... 详细信息

利用冷冻塑形法制备了具有定向孔隙结构的大孔磷酸钙骨水泥支架。利用扫描电镜(scanning electron microscope,SEM)和X射线衍射(X-ray diffraction,XRD)对材料的孔隙结构和物相进行了研究。SEM照片显示:多孔磷酸钙骨水泥具有与冰晶生长方向一致的相互连通的大孔。开口大孔的尺寸在径向能达到150～200μm,在轴向能达到500～1000μm。孔隙的大小可以通过改变冷冻参数进行调节。XRD谱显示:多孔磷酸钙骨水泥中的主要相为弱结晶的羟基磷灰石。材料的孔隙率可以通过调整液固比在70%到90%之间进行调节。实验制备的大孔磷酸钙骨水泥支架是很有希望的骨组织工程支架材料。

关键词：磷酸钙骨水泥定向孔隙羟基磷灰石孔隙率冷冻塑形法

Biaxial stretching of polytetrafluoroethylene in industrial scale to fabricate medical ePTFE membrane with node-fibril microstructure

在线全文

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2023年第1期10卷 1161-1177页

作者： Gang wang Yusheng Feng Caiyun Gao Xu Zhang Qunsong wang Jie Zhang Hongjie Zhang YongqiangWu Xin Li Lin wang ye Fu Xiaoye Yu Deyuan Zhang Jianxiong Liu jiandong Ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China R&D Center Lifetech Scientific(Shenzhen)Co.Ltd.Shenzhen 518057China R&D Center Lifevalve Medical Scientific Co.Ltd.Shenzhen 518057China

Expanded polytetrafluoroethylene(ePTFE)is promising in biomedical fields such as covered stents and plastic surgery owing to its excellent biocompatibility and mechanical ***,ePTFE material prepared by the traditional biaxial stretching process is with thicker middle and thinner sides due to the bowing effect,which poses a major problem in industrial-scale *** solve this problem,we design an olive-shaped winding roller to provide the middle part of the ePTFE tape with a greater longitudinal stretching amplitude than the two sides,so as to make up for the excessive longitudinal retraction tendency of the middle part when it is transversely *** as-fabricated ePTFE membrane has,as designed,uniform thickness and node-fibril *** addition,we examine the effects of mass ratio of lubricant to PTFE powder,biaxial stretching ratio and sintering temperature on the performance of the resultant ePTFE ***,the relation between the internal microstructure of the ePTFE membrane and its mechanical properties is *** stable mechanical properties,the sintered ePTFE membrane exhibits satisfactory biological *** make a series of biological assessments including in vitro hemolysis,coagulation,bacterial reverse mutation and in vivo thrombosis,intracutaneous reactivity test,pyrogen test and subchronic systemic toxicity test;all of the results meet the relevant international *** muscle implantation of the sintered ePTFE membrane into rabbits indicates acceptable inflammatory reactions of our sintered ePTFE membrane fabricated on industrial *** a medical-grade raw material with the unique physical form and condensed-state microstructure is expected to afford an inert biomaterial potentially for stent-graft membrane.

关键词： biomedical polymer medical-grade raw material expanded polytetrafluoroethylene olive roller polymer processing biaxial stretching

‘Invisible’ orthodontics by polymeric ‘clear’ aligners molded on 3D-printed personalized dental models

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Regenerative Biomaterials 2022年第1期9卷 1-12页

作者： Xiaoye Yu Guanghui Li Yikan Zheng Jingming Gao ye Fu Qunsong wang Lei Huang Xiaogang Pan jiandong Ding State Key Laboratory of Molecular Engineering of Polymers Department of Macromolecular ScienceFudan UniversityShanghai 200438China Department of Orthodontics Shanghai Ninth People’s HospitalCollege of StomatologyShanghai Jiao Tong University School of MedicineNational Clinical Research Center for Oral DiseasesShanghai Key Laboratory of Stomatology&Shanghai Research Institute of StomatologyShanghai 200011China R&D Center EA Medical Device Technologies Co.Ltd.Wuxi 214174China

The malalignment of teeth is treated classically by metal braces with alloy wires,which has an unfavorable influence on the patients appearance during the *** the development of digitization,computer simulation and three-dimensional(3D)printing technology,herein,a modern treatment was tried using clear polymeric aligners,which were fabricated by molding polyurethane films via thermoforming on the 3D-printed personalized dental *** key parameters of photocurable 3D printing of dental models and the mechanical properties of the clear aligner film material were *** precision of a 3D-printed dental model mainly relied on characteristics of photocurable resin,the resolution of light source and the exposure condition,which determined the eventual shape of the molded clear aligner and thus the orthodontic treatment *** biocompatibility of the polyurethane filmmaterial was confirmed through cytotoxicity and hemolysis tests in *** a series of 3D-printed personalized dental models and finite element analysis to predict and plan the fabrication and orthodontic processes,corresponding clear aligners were fabricated and applied in animal experiments,which proved the efficacy and biocompatibility in *** treatments of 120 orthodontic cases were finally carried out with success,which highlights the advantage of the clear aligners as an esthetic,compatible and efficient appliance.

关键词： 3D printing polymer biomaterial clear aligner orthodontics

Thiamine-modified metabolic reprogramming of human pluripotent stem cell-derived cardiomyocyte under space microgravity

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Signal Transduction and Targeted Therapy 2024年第5期9卷 2132-2142页

作者： Xinglong Han Lina Qu Miao Yu Lingqun ye Liujia Shi Guangfu ye Jingsi Yang Yaning wang Hao Fan Yong wang yingjun Tan Chunyan wang Qi Li Wei Lei Jianghai Chen Zhaoxia Liu Zhenya Shen Yinghui Li Shijun Hu Department of Cardiovascular Surgery of the First Affiliated Hospital&Institute for Cardiovascular Science State Key Laboratory of Radiation Medicine and ProtectionSuzhou Medical CollegeSoochow UniversitySuzhouChina State Key Laboratory of Space Medicine China Astronaut Research and Training CenterBeijingChina Department of Hand Surgery Union HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhanChina

During spaceflight,the cardiovascular system undergoes remarkable adaptation to microgravity and faces the risk of cardiac ***,the effects and mechanisms of microgravity on cardiac morphology,physiology,metabolism,and cellular biology need to be further *** China started constructing the China Space Station(CSS)in 2021,we have taken advantage of the Shenzhou-13 capsule to send human pluripotent stem cell-derived cardiomyocytes(hPSC-CMs)to the Tianhe core module of the *** this study,hPSC-CMs subjected to space microgravity showed decreased beating rate and abnormal intracellular calcium *** and transcriptomic analyses revealed a battery of metabolic remodeling of hPSC-CMs in spaceflight,especially thiamine *** microgravity condition blocked the thiamine intake in *** decline of thiamine utilization under microgravity or by its antagonistic analog amprolium affected the process of the tricarboxylic acid *** decreased ATP production,which led to cytoskeletal remodeling and calcium homeostasis imbalance in *** importantly,in vitro and in vivo studies suggest that thiamine supplementation could reverse the adaptive changes induced by simulated *** study represents the first astrobiological study on the China Space Station and lays a solid foundation for further aerospace biomedical *** data indicate that intervention of thiamine-modified metabolic reprogramming in human cardiomyocytes during spaceflight might be a feasible countermeasure against microgravity.

关键词： programming battery modified

Understanding the educational inequalities in suicide attempts and their mediators:a Mendelian randomisation study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

General Psychiatry 2024年第1期37卷 133-142页

作者： Jiahao Zhu Houpu Liu Rui Gao Lilu Ding Jing wang ye Yang Dan Zhou yingjun Li Department of Epidemiology|and Health Statistics School of Public HealthHangzhou Medical CollegeHangzhouZhejiangChina Vanderbit Genetics Institute Vanderbilt University Medical CenterNashvilleTennesseeUSA School of Public Health and the Second Afliated Hospital Zhejiang University Schol of MedicineHangzhouZhejiangChina

Background Educational inequalities in suicide have become increasingly prominent over the past *** modifiable risk factors that serve as intermediaries in the impact of low educational attainment on suicide has the potential to reduce health *** To examine the risk factors that mediate the relationship between educational attainment and suicide attempts and quantify their contributions to the mediation *** We conducted a two-sample Mendelian randomisation(MR)analysis to estimate the causal effect of educational attainment on suicide attempts,utilising genome-wide association study summary statistics from the Integrative Psychiatric Research(iPSYCH;6024 cases and 44240 controls)and FinnGen(8978 cases and 368299 controls).We systematically evaluated 42 putative mediators within the causal pathway connecting reduced educational attainment to suicide attempts and employed two-step and multivariable MR to quantify the proportion of the mediated *** In the combined analysis of iPSYCH and FinnGen,each standard deviation(SD)decrease in genetically predicted educational attainment(equating to 3.4 years of education)was associated with a 105%higher risk of suicide attempts(odds ratio(OR):2.05;95%confidence interval(Cl):1.81 to 2.31).0f the 42 risk factors analysed,the two-step MR identified five factors that mediated the association between educational attainment and suicide *** respective proportions of mediation were 47%(95%Cl:29%to 66%)for smoking behaviour,36%(95%Cl:0%to 84%)for chronic pain,49%(95%Cl:36%to 61%)for depression,35%(95%Cl:12%to 59%)for anxiety and 26%(95%Cl:18%to 34%)for *** MR implicated these five mediators collectively,accounting for 68%(95%Cl:40%to 96%)of the total *** This study identified smoking,chronic pain and mental disorders as primary intervention targets for attenuating suicide risk attributable to lower educational levels in the European population.

关键词： effect. random inequalities