Objective Graft rejection, with the possibility of a violent immune response, may be severe and life threatening. Our aim was to thoroughly investigate the biocompatibility and immunotoxicology of collagen-based derma...Objective Graft rejection, with the possibility of a violent immune response, may be severe and life threatening. Our aim was to thoroughly investigate the biocompatibility and immunotoxicology of collagen-based dermal matrix(DM) before assessment in clinical trials. Methods DM was subcutaneously implanted in BALB/c mice in two doses to induce a potential immune response. The spleen and lymph nodes were assessed for shape, cell number, cell phenotype via flow cytometry, cell activation via CCK8 kit, Annexin V kit, and Ki67 immunostaining. Serum samples were used to measure antibody concentration by enzyme-linked immunosorbent assay. Local inflammation was analyzed by histology and immunohistochemistry staining. Data analysis was performed by one-way ANOVA and non-parametric tests. Results Our data illustrate that the spleen and lymph node sizes were similar between the negative control mice and mice implanted with DM. However, in the high-dose DM(DM-H) group, the total cell populations in the spleen and lymph nodes, T cells and B cells in the spleen had slight increases in prophase, and the low-dose DM(DM-L) group did not display gross abnormities. Moreover, DM-H initiated moderate cell activation and proliferation in the early phase post-immunization, whereas DM-L did not. Neither DM-H nor DM-L implantation noticeably increased IgM and IgG serum concentrations. Examination of the local cellular response revealed only benign cell infiltration and TNF-α expression in slides of DM in the early phase. Conclusion Overall, DM-H may have induced a benign temporary acute immune response post-implantation, whereas DM-L had quite low immunogenicity. Thus, this DM can be regarded as a safe product.展开更多
Objective The aim of this study was to investigate the effects of Si O2 on fibrocytes and whether fibrocytes participate in silicosis in vivo. Methods A macrophagocyte（AM）/fibrocyte coculture system was established,...Objective The aim of this study was to investigate the effects of Si O2 on fibrocytes and whether fibrocytes participate in silicosis in vivo. Methods A macrophagocyte（AM）/fibrocyte coculture system was established, and AMs were treated with 100 μg/mL SiO 2. Flow cytometry was used to detect the number of fibrocytes. Real‐time PCR was performed to measure the expression of collagen I, collagen III, and α‐SMA mR NA. The levels of collagen I, collagen III, and TGF‐β1 protein were determined by ELISA. Immunohistochemical staining was performed to measure α‐SMA protein expression. A rat silicosis model was induced by intratracheal instillation of SiO 2. Lung histopathological evaluation was conducted using HE and Masson＇s trichrome staining after 1 and 9 weeks. The number of fibrocytes in peripheral blood or lung tissue of rat was detected by flow cytometry. Double‐color immunofluorescence was applied to identify fibrocytes in the lung tissue. Results Peripheral blood monocytes were found to differentiate into fibrocytes in vitro in a time‐dependent manner, and exposure to crystalline silica might potentiate fibrocyte differentiation. In addition, fibrocytes were able to migrate from peripheral blood to the lung tissue, and the number of fibrocytes was increased after SiO 2 exposure. Conclusion Silica exposure potentiates fibrocyte differentiation, and fibrocytes may participate in silicosis in vivo.展开更多
To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforc...To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforced polymer(CFRP)and aluminum components for a robotic aircraft assembly system.To meet the specific functional requirements for blind rivet installation on CFRP and aluminum materials,additional modules are incorporated on the end effector aside of the basic processing modules for drilling.And all of these processing modules allow for a onestep-drilling-countersinking process,hole inspection,automatic rivet feed,rivet geometry check,sealant application,rivet insertion and installation.Besides,to guarantee the better quality of the hole drilled and joints riveted,several online detection and adjustment measures are applied to this end effector,including the reference detection and perpendicular calibration,which could effectively ensure the positioning precision and perpendicular accuracy as demanded.Finally,the test result shows that this end effector is capable of producing each hole to a positioning precision within ±0.5 mm,aperpendicular accuracy within 0.3°,a diameter tolerance of H8,and a countersink depth tolerance of±0.01 mm.Moreover,it could drill and rivet up to three joints per minute,with acceptable shearing and tensile strength.展开更多
The Paleogene and Neogene oil and gas in the western Qaidam basin have a regular distribution in three concentric zones from the edge to the center of the basin. Natural gas mainly occurs in the inner zone, and the ga...The Paleogene and Neogene oil and gas in the western Qaidam basin have a regular distribution in three concentric zones from the edge to the center of the basin. Natural gas mainly occurs in the inner zone, and the gas-oil ratio of the northern area of the basin is significantly higher than that of the southern area. Large amounts of carbon isotope data of natural gas, plotted in X- shaped and comprehensive identification diagrams for the southern area and northern area, respectively, were used to identify the types of natural gas. The large-scale distribution of natural gas is highly consistent with the Ro values of major source rocks, but is poorly correlated with the type of organic matter. This indicates that the main controlling factor of natural gas distribution is organic matter maturity, and the kerogen types act as the basis for the formation of different types of natural gas. Paleouplifts and squeezed anticlines near hydrocarbon generation depression centers, which are major natural gas-rich regions, control the migration directions of natural gas, while hydrocarbon migration pathways and fault systems connecting gas sources are the most important factors for natural gas reservoir formation in the inner basin. Therefore, favorable zones for natural gas distribution can be predicted on the basis of the distribution of thermal evolution and the gas generation intensity of major source rocks as well as the structural map. The Shizigou-Youshashan- Yingdong-Dawusi, Youquanzi -Kaitemilike - Youdunzi, and Xiaoliangshan - Nanyishan - Dafengshan structural belts are favorable zones for natural gas accumulation. This study has important theoretical and practical significance for future natural gas exploration.展开更多
文摘基于密度泛函理论,在B3LYP/6-311++G(d,p)水平对新精神活性物质乙卡西酮进行结构优化,并在相同水平计算了其拉曼光谱和红外光谱.使用标准样品,实验测定了乙卡西酮的拉曼光谱和红外光谱,实验结果与理论计算非常吻合.势能分布(Potential energy distribution,PED)分析对谱峰进行了归属,实验和理论研究对照表明,乙卡西酮的拉曼特征峰为1001、1599、1694、2891、2936和3071 cm-1;红外吸收特征峰为698、1694、2734和2934 cm-1.研究发现,乙卡西酮苯环结构、C=O对拉曼光谱和红外光谱影响较为明显,而拉曼光谱结合红外光谱将更加有助于卡西酮类物质的鉴定,取代基团对光谱的贡献是区分卡西酮类物质的关键.本研究提供了乙卡西酮的拉曼光谱和红外光谱,并对其进行了归属,研究将对乙卡西酮及其它卡西酮类物质的光谱法快速鉴定提供重要借鉴和参考.
基金supported by the National Natural Science Foundation of China [No.31470915]Shenzhen Science and Technology Project [No.JCYJ20170817140537062]+1 种基金the Fundamental Research Funds for the Central Universities [No.YWF-18-BJ-J-217]the 111 Project [No.B13003]
文摘Objective Graft rejection, with the possibility of a violent immune response, may be severe and life threatening. Our aim was to thoroughly investigate the biocompatibility and immunotoxicology of collagen-based dermal matrix(DM) before assessment in clinical trials. Methods DM was subcutaneously implanted in BALB/c mice in two doses to induce a potential immune response. The spleen and lymph nodes were assessed for shape, cell number, cell phenotype via flow cytometry, cell activation via CCK8 kit, Annexin V kit, and Ki67 immunostaining. Serum samples were used to measure antibody concentration by enzyme-linked immunosorbent assay. Local inflammation was analyzed by histology and immunohistochemistry staining. Data analysis was performed by one-way ANOVA and non-parametric tests. Results Our data illustrate that the spleen and lymph node sizes were similar between the negative control mice and mice implanted with DM. However, in the high-dose DM(DM-H) group, the total cell populations in the spleen and lymph nodes, T cells and B cells in the spleen had slight increases in prophase, and the low-dose DM(DM-L) group did not display gross abnormities. Moreover, DM-H initiated moderate cell activation and proliferation in the early phase post-immunization, whereas DM-L did not. Neither DM-H nor DM-L implantation noticeably increased IgM and IgG serum concentrations. Examination of the local cellular response revealed only benign cell infiltration and TNF-α expression in slides of DM in the early phase. Conclusion Overall, DM-H may have induced a benign temporary acute immune response post-implantation, whereas DM-L had quite low immunogenicity. Thus, this DM can be regarded as a safe product.
基金supported by grants from the National Natural Science Foundation of China(No.81472954)
文摘Objective The aim of this study was to investigate the effects of Si O2 on fibrocytes and whether fibrocytes participate in silicosis in vivo. Methods A macrophagocyte（AM）/fibrocyte coculture system was established, and AMs were treated with 100 μg/mL SiO 2. Flow cytometry was used to detect the number of fibrocytes. Real‐time PCR was performed to measure the expression of collagen I, collagen III, and α‐SMA mR NA. The levels of collagen I, collagen III, and TGF‐β1 protein were determined by ELISA. Immunohistochemical staining was performed to measure α‐SMA protein expression. A rat silicosis model was induced by intratracheal instillation of SiO 2. Lung histopathological evaluation was conducted using HE and Masson＇s trichrome staining after 1 and 9 weeks. The number of fibrocytes in peripheral blood or lung tissue of rat was detected by flow cytometry. Double‐color immunofluorescence was applied to identify fibrocytes in the lung tissue. Results Peripheral blood monocytes were found to differentiate into fibrocytes in vitro in a time‐dependent manner, and exposure to crystalline silica might potentiate fibrocyte differentiation. In addition, fibrocytes were able to migrate from peripheral blood to the lung tissue, and the number of fibrocytes was increased after SiO 2 exposure. Conclusion Silica exposure potentiates fibrocyte differentiation, and fibrocytes may participate in silicosis in vivo.
基金supported by the National Natural Science Foundations of China(Nos.5157051626,51475225)
文摘To fulfill the demands for higher quality,efficiency and flexibility in aviation industry,a multi-functional end effector is designed to automate the drilling and riveting processes in assembling carbon fiber reinforced polymer(CFRP)and aluminum components for a robotic aircraft assembly system.To meet the specific functional requirements for blind rivet installation on CFRP and aluminum materials,additional modules are incorporated on the end effector aside of the basic processing modules for drilling.And all of these processing modules allow for a onestep-drilling-countersinking process,hole inspection,automatic rivet feed,rivet geometry check,sealant application,rivet insertion and installation.Besides,to guarantee the better quality of the hole drilled and joints riveted,several online detection and adjustment measures are applied to this end effector,including the reference detection and perpendicular calibration,which could effectively ensure the positioning precision and perpendicular accuracy as demanded.Finally,the test result shows that this end effector is capable of producing each hole to a positioning precision within ±0.5 mm,aperpendicular accuracy within 0.3°,a diameter tolerance of H8,and a countersink depth tolerance of±0.01 mm.Moreover,it could drill and rivet up to three joints per minute,with acceptable shearing and tensile strength.
基金supported financially by the National Science and Technology Major Project"Chinese large gasfields’formation conditions,accumulation and objective evaluation"(2011ZX05007)the Major Special Project of Chinese Petroleum Development Technologies"A study on comprehensive supporting technologies for building oil-gas field of ten million tons in Qaidam basin"(2011E-03)
文摘The Paleogene and Neogene oil and gas in the western Qaidam basin have a regular distribution in three concentric zones from the edge to the center of the basin. Natural gas mainly occurs in the inner zone, and the gas-oil ratio of the northern area of the basin is significantly higher than that of the southern area. Large amounts of carbon isotope data of natural gas, plotted in X- shaped and comprehensive identification diagrams for the southern area and northern area, respectively, were used to identify the types of natural gas. The large-scale distribution of natural gas is highly consistent with the Ro values of major source rocks, but is poorly correlated with the type of organic matter. This indicates that the main controlling factor of natural gas distribution is organic matter maturity, and the kerogen types act as the basis for the formation of different types of natural gas. Paleouplifts and squeezed anticlines near hydrocarbon generation depression centers, which are major natural gas-rich regions, control the migration directions of natural gas, while hydrocarbon migration pathways and fault systems connecting gas sources are the most important factors for natural gas reservoir formation in the inner basin. Therefore, favorable zones for natural gas distribution can be predicted on the basis of the distribution of thermal evolution and the gas generation intensity of major source rocks as well as the structural map. The Shizigou-Youshashan- Yingdong-Dawusi, Youquanzi -Kaitemilike - Youdunzi, and Xiaoliangshan - Nanyishan - Dafengshan structural belts are favorable zones for natural gas accumulation. This study has important theoretical and practical significance for future natural gas exploration.
