检索结果-南通市图书馆

Mutual regulation of microglia and astrocytes after Gas6 inhibits spinal cord injury

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Neural Regeneration Research 2025年第2期20卷 557-573页

作者： Jiewen Chen Xiaolin Zeng Le Wang Wenwu Zhang Gang Li Xing Cheng Peiqiang Su Yong Wan Xiang Li Department of Spine Surgery The First Affiliated HospitalSun Yat-sen UniversityGuangzhouGuangdong ProvinceChina Guangdong province key laboratory of Orthopedics and Traumatology GuangzhouGuangdong ProvinceChina

Invasive inflammation and excessive scar formation are the main reasons for the difficulty in repairing nervous tissue after spinal cord *** and astrocytes play key roles in the spinal cord injury micro-environment and share a close ***,the mechanisms involved remain *** this study,we found that after spinal cord injury,resting microglia(M0)were polarized into pro-inflammatory phenotypes(MG1 and MG3),while resting astrocytes were polarized into reactive and scar-forming *** expression of growth arrest-specific 6(Gas6)and its receptor Axl were significantly down-regulated in microglia and astrocytes after spinal cord *** vitro experiments showed that Gas6 had negative effects on the polarization of reactive astrocytes and pro-inflammatory microglia,and even inhibited the cross-regulation between *** further demonstrated that Gas6 can inhibit the polarization of reactive astrocytes by suppressing the activation of the Yes-associated protein signaling ***,in turn,inhibited the polarization of pro-inflammatory microglia by suppressing the activation of the nuclear factor-κB/p65 and Janus kinase/signal transducer and activator of transcription signaling *** vivo experiments showed that Gas6 inhibited the polarization of pro-inflammatory microglia and reactive astrocytes in the injured spinal cord,thereby promoting tissue repair and motor function ***,Gas6 may play a role in the treatment of spinal cord *** can inhibit the inflammatory pathway of microglia and polarization of astrocytes,attenuate the interaction between microglia and astrocytes in the inflammatory microenvironment,and thereby alleviate local inflammation and reduce scar formation in the spinal cord.

关键词： astrocytes Axl cell polarization Gas6 Hippo signal inflammatory micro-environment intercellular interaction microglia single-cell sequencing spinal cord injury

3D Printing of Tough Hydrogel Scaffolds with Functional Surface Structures for Tissue Regeneration

在线全文

学校读者我要写书评

暂无评论

Nano-Micro Letters 2025年第2期17卷 18-45页

作者： Ke Yao Gaoying Hong Ximin Yuan Weicheng Kong Pengcheng Xia Yuanrong Li Yuewei Chen Nian Liu Jing He Jue Shi Zihe Hu Yanyan Zhou Zhijian Xie Yong He State key laboratory of Fluid Power and Mechatronic Systems School of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Liangzhu laboratory Zhejiang UniversityHangzhou 310027People’s Republic of China key laboratory of 3D Printing Process and equipment of Zhejiang province College of Mechanical EngineeringZhejiang UniversityHangzhou 310027People’s Republic of China Stomatology Hospital School of StomatologyZhejiang University School of MedicineHangzhou 310027People’s Republic of China State key laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001People’s Republic of China Institute of Digital Medicine Nanjing First HospitalNanjing Medical UniversityNanjing 210006People’s Republic of China

Hydrogel scaffolds have numerous potential applications in the tissue engineering ***,tough hydrogel scaffolds implanted in vivo are seldom reported because it is difficult to balance biocompatibility and high mechanical *** by Chinese ramen,we propose a universal fabricating method(printing-P,training-T,cross-linking-C,PTC&PCT)for tough hydrogel scaffolds to fill this ***,3D printing fabricates a hydrogel scaffold with desired structures(P).Then,the scaffold could have extraordinarily high mechanical properties and functional surface structure by cycle mechanical training with salting-out assistance(T).Finally,the training results are fixed by photo-cross-linking processing(C).The tough gelatin hydrogel scaffolds exhibit excellent tensile strength of 6.66 MPa(622-fold untreated)and have excellent ***,this scaffold possesses functional surface structures from nanometer to micron to millimeter,which can efficiently induce directional cell ***,this strategy can produce bionic human tissue with mechanical properties of 10 kPa-10 MPa by changing the type of salt,and many hydrogels,such as gelatin and silk,could be improved with PTC or PCT *** experiments show that this scaffold can effectively promote the new generation of muscle fibers,blood vessels,and nerves within 4 weeks,prompting the rapid regeneration of large-volume muscle loss injuries.

关键词： 3D printing Tough hydrogel scaffold Functional surface structure Tissue regeneration Biomaterials

Atomistic evaluation of tension–compression asymmetry in nanoscale body-centered-cubic AlCrFeCoNi high-entropy alloy

在线全文

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第1期33卷 613-622页

作者：邢润龙刘雪鹏 Anhui province key laboratory of Aerospace Structural Parts forming Technology and equipment Institute of Industry and Equipment TechnologyHefei University of TechnologyHefei 230009China

The tension and compression of face-centered-cubic high-entropy alloy(HEA) nanowires are significantly asymmetric, but the tension–compression asymmetry in nanoscale body-centered-cubic(BCC) HEAs is still unclear. In this study,the tension–compression asymmetry of the BCC Al Cr Fe Co Ni HEA nanowire is investigated using molecular dynamics simulations. The results show a significant asymmetry in both the yield and flow stresses, with BCC HEA nanowire stronger under compression than under tension. The strength asymmetry originates from the completely different deformation mechanisms in tension and compression. In compression, atomic amorphization dominates plastic deformation and contributes to the strengthening, while in tension, deformation twinning prevails and weakens the HEA *** tension–compression asymmetry exhibits a clear trend of increasing with the increasing nanowire cross-sectional edge length and decreasing temperature. In particular, the compressive strengths along the [001] and [111] crystallographic orientations are stronger than the tensile counterparts, while the [110] crystallographic orientation shows the exactly opposite trend. The dependences of tension–compression asymmetry on the cross-sectional edge length, crystallographic orientation,and temperature are explained in terms of the deformation behavior of HEA nanowire as well as its variations caused by the change in these influential factors. These findings may deepen our understanding of the tension–compression asymmetry of the BCC HEA nanowires.

关键词： high-entropy alloys body-centered-cubic nanowire tension–compression asymmetry atomistic simulations

Effects of Cooling Rate and Component on the Microstructure and Mechanical Properties of Mg–Zn–Y Alloys

在线全文

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2015年第1期28卷 7-14页

作者： Shuang Shao Yong Liu Chun-Shui Xu Ying-Xuan Xu Bin Wu Xiao-Shu Zeng Xian-Feng Lu Xiang-Jie Yang key laboratory of Near Net forming of Jiangxi province Nanchang University

The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates（Rc） from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0：45：45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction（Vf） of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.

关键词： Mg–Zn–Y alloys Microstructural characterization Compressive strength Cooling rate Interdependence theory

Control over Mechanical Properties and Microstructure of BR1500HS Hot-stamped Parts

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2014年第6期21卷 606-613页

作者： Bai-liang ZHUANG Zhong-de SHAN Chao JIANG Xin-ya LI State key laboratory of Advanced forming Technology and equipment of CAM jiangsu Institute China Academy of Machinery Science and Technology

The hot stamping processing parameters are of critical importance in transforming ultra-high-strength steel （UHSS） into high-quality parts, which were studied by mechanical properties tests, metallographic observations and calculation analysis method based on hot stamping experiments and numerical simulation technology, the mechanical properties, thickness, dimensional accuracy, and microstructure of the hot formed parts are analyzed to determine the influence of different processing parameters for UHSS parts formed from BR1500HS. The results indicate that the quenching time had the most significant impact on the mechanical properties of the parts, and longer quenching time resulted in better mechanical properties. In addition, the pressing speed had a significant influence on the thick ness of the formed parts, and the part-opening temperature had the most significant effect on the dimensional accura cy of the parts. And to get hot stamped parts with excellent quality, the optimum process conditions should be set as heating temperature of 930 ℃, soaking time of 4 min, stamping force of 7 MPa, pressing speed of 75 mm/s, quench ing time of 15 s, and water-flow rate of 1.1 m/s.

关键词： hot forming processing parameter mechanical property microstructure

Synthesis of Polybutadienes with Controllable Microstructure by a Novel Binary Nd(3-NBSO_3)_3/Alkylaluminum Catalyst System

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Polymer Science 2015年第3期33卷 475-480页

作者： Ji-qin Wen Xue-quan Zhang 代全权 key laboratory of Synthetic Rubber Changchun Institute of Applied ChemistryChinese Academy of Sciences jiangsu province Institute for Medical equipment Testing

The polymerization of 1,3-butadiene was examined by using a novel halogen-free neodymium m-nitrobenzenesulfonate （Nd（3-NBSOa）3·donors）/alkylaluminum binary catalyst system. The catalyst showed fairly high activity and controllable selectivity. The microstructure of the resultant polymer was adjustable by variation of electron donor and/or the alkylaluminum. ^13C-NMR and thermal analysis demonstrate that the produced polybutadienes have stereo-block chain structures of cis-1,4 and trans-1,4 segments with adjustable Tm and To. The neodymium sulfonate-based catalyst is believed to be significant in regulating the chain structure of polydienes and in exploring 1,3-diene polymerization mechanism.

关键词： Polybutadiene Microstructure Ziegler-Natta polymerization.

A Model for Predicting Dynamic Cutting Forces in Sand Mould Milling with Orthogonal Cutting

在线全文

学校读者我要写书评

暂无评论

Chinese Journal of Mechanical Engineering 2018年第6期31卷 95-105页

作者： Zhong-De Shan Fu-Xian Zhu State key laboratory of Advanced forming Technology and equipment China Academy of Machinery Science TechnologyBeijing 100083China jiangsu University of Technology Changzhou 213001China

Cutting force is one of the research hotspots in direct sand mould milling because the cutting force directly a ects the machining quality and tool wear. Unlike metals, sand mould is a heterogeneous discrete deposition material. There is still a lack of theoretical research on the cutting force. In order to realize the prediction and control of the cut?ting force in the sand mould milling process, an analytical model of cutting force is proposed based on the unequal division shear zone model of orthogonal cutting. The deformation velocity relations of the chip within the orthogonal cutting shear zone are analyzed first. According to the flow behavior of granular, the unequal division shear zone model of sand mould is presented, in which the governing equations of shear strain rate, strain and velocity are estab?lished. The constitutive relationship of quasi?solid–liquid transition is introduced to build the 2D constitutive equation and deduce the cutting stress in the mould shear zone. According to the cutting geometric relations of up milling with straight cutting edge and the transformation relationship between cutting stress and cutting force, the dynamic cutting forces are predicted for di erent milling conditions. Compared with the experimental results, the predicted results show good agreement, indicating that the predictive model of cutting force in milling sand mould is validated. Therefore, the proposed model can provide the theoretical guidance for cutting force control in high e ciency mill?ing sand mould.

关键词： green manufacture Cutting force Sand mould milling Orthogonal cutting Quasi?solid–liquid transition

Insights into the differences in leaf functional traits of heterophyllous Syringa oblata under different light intensities

在线全文

学校读者我要写书评

暂无评论

Journal of Forestry Research 2015年第3期26卷 613-621页

作者： Hongguang Xiao Congyan Wang Jun Liu Lei Wang Daolin Du School of the Environment and Safety Engineering Institute of Environment and Ecology Jiangsu University key laboratory of Modern Agricultural equipment and Technology Ministry of Education and Jiangsu ProvinceJiangsu University

Many plants exhibit heterophylly; the spatially and temporally remarkable ontogenetic differences in leaf morphology may play an adaptative role in their success under diverse habitats. Thus, this study aimed to gain insights into differences in leaf functional traits of heterophyllous Syringa oblata Lindl., which has been widely used as an ornamental tree around the world under different light intensities in East China. No significant differences existed in specific leaf area （SLA） between lanceolate- and heart-shaped leaves. Differ- ences in the investment per unit of light capture surface area deployed between lanceolate- and heart-shaped leaves may benot obvious. This may be attributing to the fact that single leaf wet and dry weight of heart-shaped leaves were significantly higher than those of lanceolate leaves but leaf length and leaf thickness of heart-shaped leaves were significantly lower than those of lanceolate leaves. The SLA of shade trees was sig- nificantly higher than that of sun trees. The investment per unit of light capture surface of shade trees was lower than that of sun trees, making it possible to increase light capture and use efficiency in low-light environments. The phenotypic plas- ticity of most leaf functional traits of lanceoiate leaves was higher than those of heart-shaped leaves because the former is the juvenile and the latter is the adult leaf shape during the process of phylogenetic development of S. oblate. The higher range of phenotypic plasticity of leaf thickness and leaf moisture for sun trees may be beneficial to obtain a more efficient control of water loss and nutrient deprivation in high- light environments, and the lower range of phenotypic plas- ticity of single leaf wet and dry weight, and SLA for shade trees may gain an advantage to increase resource （especially light） capture and use efficiency in low-light environments. In brief, the successfully ecological strategy of plants is to find an optimal mode for the trade

关键词： Heterophylly Light intensity Specific leafareas Syringa oblata Lindl.

Cross-flow fan on multi-dimensional airflow field of air screen cleaning system for rice grain

在线全文

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2022年第4期15卷 223-235页

作者： Yaquan Liang Zhong Tang Hao Zhang Yaoming Li Zhao Ding Zhan Su key laboratory of Modern Agricultural equipment and Technology of Ministry of Education Jiangsu UniversityZhenjiang 212013JiangsuChina key laboratory of Crop Harvesting equipment Technology of Zhejiang province Jinhua 321017ZhejiangChina

With the advancement of agricultural mechanization and the development of combine harvesters, cleaning devices play a very important role in the grain harvesting process. In this study, the DFPF-25 type material floating velocity measuring device was used to measure the suspension velocity of each component of the grain material. Secondly, the DFQX-3 cleaning device was used to conduct the airflow field test, then the fluid simulation of the cleaning shoe was carried out. The results showed that the simulation and experimental results were in a good agreement under the conditions of single fan and double fan. The high-speed flow velocity formed by the double fan system at the tail of the cleaning shoe was 4.76 m/s (simulation) and 4.03 m/s (experiment), which had outstanding cleaning effects on unfilled grains, long stems, and short stems. To sum up, the installation of the cross-flow fan at the rear of the cleaning shoe has a positive effect on the cleaning effect of the combine harvester, and the double-fan cleaning structure composed of the cross-flow fan and the centrifugal fan can significantly improve the cleaning effect.

关键词： double-fan structure CFD cross-flow fan velocity contour rice grain