Large-module rack of the Three Gorges shiplift is manufactured by casting and machining, which is unable to avoid slag inclusions and surface cracks. To ensure its safety in the future service, studying on crack propa...Large-module rack of the Three Gorges shiplift is manufactured by casting and machining, which is unable to avoid slag inclusions and surface cracks. To ensure its safety in the future service, studying on crack propagation rule and the residual life estimation method of large-module rack is of great significance. The possible crack distribution forms of the rack in the Three Gorges shiplift were studied. By applying moving load on the model in FRANC3 D and ANSYS, quantitative analyses of interference effects on double cracks in both collinear and offset conditions were conducted. The variation rule of the stress intensity factor(SIF) influence factor, RK, of double collinear cracks changing with crack spacing ratio, RS, was researched. The horizontal and vertical crack spacing threshold of double cracks within the design life of the shiplift were obtained, which are 24 and 4 times as large as half of initial crack length, c0, respectively. The crack growth rates along the length and depth directions in the process of coalescence on double collinear cracks were also studied.展开更多
目的:研究O-GlcNAcylation调节蛋白激酶C受体1(receptor for activated C kinase 1,Rack1)的稳定性在SHH型髓母细胞瘤(SHH type medulloblastoma,SHH-MB)形成中的功能作用。方法:选取中国人民解放军西部战区总医院临床肿瘤标本库中分子...目的:研究O-GlcNAcylation调节蛋白激酶C受体1(receptor for activated C kinase 1,Rack1)的稳定性在SHH型髓母细胞瘤(SHH type medulloblastoma,SHH-MB)形成中的功能作用。方法:选取中国人民解放军西部战区总医院临床肿瘤标本库中分子分型所确定的SHH-MB肿瘤及癌旁组织,分析样本中Rack1和O-GlcNAcylation(O-Glc NAc)的表达水平差异。对于人源髓母细胞瘤细胞系Daoy使用糖基化转移酶(OGT)抑制剂(OSMI-1)和去糖基化转移酶(OGA)抑制剂(TM-G)进行处理,通过Cell Counting Kit-8(CCK-8)法和免疫荧光染色检测肿瘤细胞增殖能力。采用O-Glc NAc酶标记系统、免疫共沉淀(Co-IP)和Western blot法判断Rack1有无发生O-Glc NAc,而后通过环己酰亚胺(CHX)实验和泛素化修饰实验证实O-GlcNAcylation对Rack1蛋白水平的影响。构建敲低Rack1的髓母细胞瘤模型,通过Cell Counting Kit-8(CCK-8)法、免疫荧光染色和划痕实验检测肿瘤细胞增殖能力。同时通过在免疫缺陷型小鼠进行异种原位肿瘤移植进行验证,在所得组织样本中(sh-NC和shRack1)使用Western blot检测下游SHH信号通路变化。结果:Rack1和O-GlcNAcylation在SHH-MB中表达水平显著增高,且Rack1表达水平和患者生存率呈负相关关系。对Daoy细胞系使用OSMI-1、TM-G处理后,发现O-Glc NAc能明显促进Daoy细胞增殖,而抑制细胞O-GlcNAc则抑制细胞增殖。分子实验证实Rack1蛋白O-GlcNAcylation可以调节其蛋白稳定性,进而促进肿瘤细胞增殖。在Daoy细胞系敲低Rack1表达,其细胞增殖能力明显低于对照组;在动物水平方面,相较于对照组,Rack1蛋白敲低的肿瘤组织增殖受到显著抑制。并且Rack1可通过调节SHH信号通路参与SHH-MB形成。结论:O-GlcNAcylation可通过调节Rack1蛋白的稳定性进而参与SHH-MB形成。展开更多
China scheduled to complete the assembly of the T-shaped Tiangong Space Station in 2022,and will enter a new stage of utilization.There are more than 20 experiment racks inside the modules,and more than 50 external on...China scheduled to complete the assembly of the T-shaped Tiangong Space Station in 2022,and will enter a new stage of utilization.There are more than 20 experiment racks inside the modules,and more than 50 external onboard payloads mounting spaces,which will support large-scale science and technology experiments during the operation.The development of internal experiment racks and external research accommodations approved during the construction has been completed,of which 4 racks in Tianhe core module,including High Microgravity Level research Rack(HMLR)and Container-less Materials Processing Rack(CMPR),have finished on-orbit tests;while other racks in Wentian and Mengtian experiment modules are under comprehensive ground tests.The Chinese Space Survey Telescope(CSST)has advanced much in the last two years with 24 pre-launch research projects funded and 4 joint science center built in preparation for CSST’s future scientific observations and operations.The systematic research planning for China’s Space Station(CSS)during 2022-2032 is updated with the researches classified into four important areas:space life sciences and human research,microgravity physical sciences,space astronomy and Earth science,and new space technologies and applications.According to the planning,more than 1000 experiments are expected to perform in CSS during the operating period.Overall,the CSS utilization missions are proceeding as planned,which will contribute to the major scientific or application output and have a positive impact on the quality of life on Earth.展开更多
在前期实验中,本实验室利用i TRAQ技术研究了柔嫩艾美耳球虫子孢子感染宿主细胞后蛋白质组学的变化,获得了一批与子孢子入侵相关的宿主蛋白。本研究以鸡肌肉的c DNA为模板,对其中活化蛋白激酶C受体1(receptor for activated C kinase1,R...在前期实验中,本实验室利用i TRAQ技术研究了柔嫩艾美耳球虫子孢子感染宿主细胞后蛋白质组学的变化,获得了一批与子孢子入侵相关的宿主蛋白。本研究以鸡肌肉的c DNA为模板,对其中活化蛋白激酶C受体1(receptor for activated C kinase1,RACK1)进行克隆、表达及纯化,结果显示,成功获得RACK1-GST融合蛋白,并作为免疫原制备兔抗RACK1-GST多克隆抗体;利用RT-q PCR和Western blot检测子孢子感染DF-1细胞过程中RACK1的m RNA转录水平和蛋白表达水平。结果显示,子孢子感染细胞24~72 h时,细胞RACK1的转录水平和蛋白表达水平均明显提高;利用抗体抑制入侵试验检测RACK1多抗对子孢子入侵细胞的影响,结果显示,100μg/m L和200μg/m L RACK1-GST抗体作用细胞后对子孢子的入侵影响不大,而300μg/m L和400μg/m L作用细胞后能明显促进子孢子的入侵。以上结果表明,宿主RACK1对球虫子孢子入侵细胞起负调控的作用,但具体机制尚需深入研究。展开更多
基金Project(0722018)supported by the China Three Gorges CorporationProject(2012KJX01)supported by the Hubei Key Laboratory of Hydroelectric Machinery Design&Maintenance,China
文摘Large-module rack of the Three Gorges shiplift is manufactured by casting and machining, which is unable to avoid slag inclusions and surface cracks. To ensure its safety in the future service, studying on crack propagation rule and the residual life estimation method of large-module rack is of great significance. The possible crack distribution forms of the rack in the Three Gorges shiplift were studied. By applying moving load on the model in FRANC3 D and ANSYS, quantitative analyses of interference effects on double cracks in both collinear and offset conditions were conducted. The variation rule of the stress intensity factor(SIF) influence factor, RK, of double collinear cracks changing with crack spacing ratio, RS, was researched. The horizontal and vertical crack spacing threshold of double cracks within the design life of the shiplift were obtained, which are 24 and 4 times as large as half of initial crack length, c0, respectively. The crack growth rates along the length and depth directions in the process of coalescence on double collinear cracks were also studied.
文摘China scheduled to complete the assembly of the T-shaped Tiangong Space Station in 2022,and will enter a new stage of utilization.There are more than 20 experiment racks inside the modules,and more than 50 external onboard payloads mounting spaces,which will support large-scale science and technology experiments during the operation.The development of internal experiment racks and external research accommodations approved during the construction has been completed,of which 4 racks in Tianhe core module,including High Microgravity Level research Rack(HMLR)and Container-less Materials Processing Rack(CMPR),have finished on-orbit tests;while other racks in Wentian and Mengtian experiment modules are under comprehensive ground tests.The Chinese Space Survey Telescope(CSST)has advanced much in the last two years with 24 pre-launch research projects funded and 4 joint science center built in preparation for CSST’s future scientific observations and operations.The systematic research planning for China’s Space Station(CSS)during 2022-2032 is updated with the researches classified into four important areas:space life sciences and human research,microgravity physical sciences,space astronomy and Earth science,and new space technologies and applications.According to the planning,more than 1000 experiments are expected to perform in CSS during the operating period.Overall,the CSS utilization missions are proceeding as planned,which will contribute to the major scientific or application output and have a positive impact on the quality of life on Earth.
