The effects of the direct current （DC） on the evolutions of hardness and morphology of the secondary phases in 7B04 aluminum alloy homogenized at 380？465 ℃ for 2 h were investigated in detail by electric conductiv...The effects of the direct current （DC） on the evolutions of hardness and morphology of the secondary phases in 7B04 aluminum alloy homogenized at 380？465 ℃ for 2 h were investigated in detail by electric conductivity measurement, hardness test, X-ray diffraction analysis, field emission scanning electron microscopy and energy dispersive spectrometry. The results show that with increasing temperature from 380 to 465 ℃, the electric conductivity of normal homogenized sample decreases from 34.9%IACS to 28.7%IACS, the hardness increases from HV 96 to HV 146, and the area fraction of secondary phase reduces from 4.5% to 1.89%. While, DC homogenized sample has a higher hardness, a lower electric conductivity and a smaller area fraction of secondary phases at the same temperature. The DC enhances the homogenization process by promoting the diffusibility of the solute atoms and the mobility of vacancy.展开更多
The effects of the two-step ageing parameters （temperature and time） on the mechanical properties and electrical conductivity of 7B04 （A1-Zn-Mg-Cu） pre-stretched thick plates were studied. The results reveal that ...The effects of the two-step ageing parameters （temperature and time） on the mechanical properties and electrical conductivity of 7B04 （A1-Zn-Mg-Cu） pre-stretched thick plates were studied. The results reveal that the initial T1 ageing contributes a major increase of the tensile strength, and the 0.2% proof stress value reaches 482 MPa after ageing for 7 h at 115℃. Behavioral differences in the tensile properties of the alloy after the two-step ageing treatment were less with the first-step ageing at 115~C for different time periods （7, 14, and 21 h）. The effects of the second ageing parameters on the properties and microstructure of the 7B04 alloy were remarkable. TEM analysis of the samples aged at Temper I （7 h at 115℃ ＋ 12 h at 160℃） and Temper II （7 h at 115℃ ＋ 16 h at 165℃） indicates that two kinds of phases, i.e. 11＇ and 11 phases, precipitate from the matrix and efficiently improve the tensile strength of the alloy, and the grain boundary precipitates are coarse and discrete. There are obvious precipitate free zones （PFZs） along the grain boundary in the microstructure of the alloy after the two-step ageing treatment.展开更多
AIM： To explore the propriety of providing hepatitis B virus （HBV） genotypes F and H with two distinct genotypes. METHODS： Eleven HBV isolates of genotype F （HBV/F） were recovered from patients living in San Fra...AIM： To explore the propriety of providing hepatitis B virus （HBV） genotypes F and H with two distinct genotypes. METHODS： Eleven HBV isolates of genotype F （HBV/F） were recovered from patients living in San Francisco, Japan, Panama, and Venezuela, and their full-length sequences were determined. Phylogenetic analysis was carded out among them along with HBV isolates previously reported. RESULTS： Seven of them clustered with reported HBV/F Isolates in the phylogenetic tree constructed on the entire genomic sequence. The remaining four flocked on another branch along with three HBV isolates formerly reported as genotype H. These seven HBV isolates, including the four in this study and the three reported, had a sequence divergence of 7.3-9.5% from the other HBV/F isolates, and differed by 〉13.7% from HBV isolates of the other six genotypes （A-E and G）. Based on a marked genomic divergence, falling just short of 〉8% separating the seven genotypes, these seven HBV/F isolates were classified into F2 subtype and the former seven into F1 subtype provisionally. In a pairwise comparison of the S-gene sequences among the 7 HBV/F2 isolates and against 47 HBV/F1 isolates as well as 136 representing the other six genotypes （A-E and G）, two clusters separated by distinct genetic distances emerged.CONCLUSION： Based on these analyses, dassifying HBV/ F isolates into two subtypes （F1 and F2） would be more appropriate than providing them with two distinct genotypes （F and H）.展开更多
The effects of homogenization treatment on microstructure, overburnt temperature and hot rolling plasticity of high strength 7B04 aluminium alloy were investigated. Under the condition of homogenization at 470 ℃, the...The effects of homogenization treatment on microstructure, overburnt temperature and hot rolling plasticity of high strength 7B04 aluminium alloy were investigated. Under the condition of homogenization at 470 ℃, the starting melting temperature of the primary eutectics in ingot of non-equilibium solidified 7B04 alloy is 478 ℃. Using two-step homogenization processing at ultra-high temperature which comprises heating the ingots to 470 ℃ at 10 ℃/ h and holding for 64 h, and then heating to 500 ℃ at 1 ℃ /h and holding for 10 h, the ingots of 7B04 aluminium alloy could safely pass the sensitive overburnt zone between 480 ℃ and 495 ℃, and the ordinary burnt phenomena of the ingots between 480 ℃ and 495 ℃ does not occur because the excess low-melting point eutectic phases in the as-cast alloy dissolve into the matrix during the two-step homogenization processing. Consequently, the hot rolling plasticity of ingot of 7B04 aluminium alloy is greatly improved.展开更多
The evolution of the microstructure and phases of the direct chill semicontinuous casting ingot of 7B04 super-high strength aluminum alloy during homogenization treatment was studied with metallographic analysis, scan...The evolution of the microstructure and phases of the direct chill semicontinuous casting ingot of 7B04 super-high strength aluminum alloy during homogenization treatment was studied with metallographic analysis, scanning electron microscopy(SEM), energy spectroscopy and differential scanning calorimetry(DSC). The results show that a considerable amount of non-equilibrium eutectics containing Al, Zn, Cu and Mg exist in the direct chill semicontinuous casting ingot of 7B04 super-high strength aluminum alloy, and their melting point is 478 ℃. During homogenization treatment at 470 ℃, these eutectics dissolve into the matrix partly, coarsen and also transform into Al2CuMg phase whose equilibrium melting point is 490 ℃ in the alloy. Moreover, the homogenization treatment at 470 ℃ for 72 h results in the disappearance of the non-equilibrium eutectics though Al2CuMg phase can not dissolve completely.展开更多
Objective To investigate the quantities of bone marrow CD5+ B lymphocytes in the patients with autoimmune hemocytopenia and the relationship between quantities of CD5+ B lymphocytes and clinical or laboratorial parame...Objective To investigate the quantities of bone marrow CD5+ B lymphocytes in the patients with autoimmune hemocytopenia and the relationship between quantities of CD5+ B lymphocytes and clinical or laboratorial parameters. Methods Quantities of CD5+ B lymphocytes in the bone marrow of 14 patients with autoimmune hemolytic anemia (AIHA) or Evans syndrome, 22 immunorelated pancytopenia (IRP) patients, and 10 normal controls were assayed by flow cytometry. The correlation between their clinical or laboratorial parameters and CD5+ B lymphocytes was analyzed. Results The quantity of CD5+ B lymphocytes of AIHA/Evans syndrome (34.64%±19.81%) or IRP patients (35.81%±16.83%) was significantly higher than that of normal controls (12.00%±1.97%, P<0.05). However, there was no significant difference between AIHA/Evans syndrome and IRP patients (P>0.05). In all hemocytopenic patients, the quantity of bone marrow CD5+ B lymphocytes showed significantly negative correlation with serum complement C3 level (r=-0.416, P<0.05). In the patients with AIHA/Evans syndrome, the quantity of bone marrow CD5+ B lymphocytes showed significantly positive correlation with serum indirect bilirubin level (r=1.00, P<0.05). In Evans syndrome patients, the quantity of CD5+ B lymphocytes in bone marrow showed significantly positive correlation with platelet-associated immunoglobulin G (r=0.761, P<0.05) and platelet-associated immunoglobulin M (r=0.925, P<0.05). The quantity of CD5+ B lymphocytes in bone marrow of all hemocytopenic patients showed significantly negative correlation with treatment response (tau-b=-0.289, P<0.05), but had no correlation with colony forming unit-erythroid (r=-0.205, P>0.05) or colony forming unit-granulocyte-macrophage colonies (r=-0.214, P>0.05). Conclusions The quantity of bone marrow CD5+ B lymphocytes in the patients with autoimmune hemocytopenia significantly increases and is correlated with disease severity and clinical response, which suggest that CD5+ B lymphocytes might play an important role in the pathogenesis of autoimmune hemocytopenia.展开更多
BACKGROUND Immunotherapy presents both promises and challenges in treating hepatocellular carcinoma(HCC)due to its complex immunological microenvironment.The role of B cells,a key part of the immune system,remains unc...BACKGROUND Immunotherapy presents both promises and challenges in treating hepatocellular carcinoma(HCC)due to its complex immunological microenvironment.The role of B cells,a key part of the immune system,remains uncertain in HCC.AIM To identify B-cell-specific signatures and reveal novel immunophenotyping and therapeutic targets for HCC.METHODS Using the Tumor Immune Single-cell Hub 2 database,we identified B-cell-related genes(BRGs)in HCC.Gene enrichment analysis was performed to explore the possible collaboration between B cells and T cells in HCC.We conducted univariate Cox regression analysis using The Cancer Genome Atlas liver HCC collection dataset to find BRGs linked to HCC prognosis.Subsequently,least absolute shrinkage and selection operator regression was utilized to develop a prognostic model with 11 BRGs.The model was validated using the International Cancer Genome Consortium dataset and GSE76427.RESULTS The risk score derived from the prognostic model emerged as an independent prognostic factor for HCC.Analysis of the immune microenvironment and cell infiltration revealed the immune status of various risk groups,supporting the cooperation of B and T cells in suppressing HCC.The BRGs model identified new molecular subtypes of HCC,each with distinct immune characteristics.Drug sensitivity analysis identified targeted drugs effective for each HCC subtype,enabling precision therapy and guiding clinical decisions.CONCLUSION We clarified the role of B cells in HCC and propose that the BRGs model offers promising targets for personalized immunotherapy.展开更多
The static and fatigue properties of 7B04 aluminum alloy structures connected by riveting and refill friction stir spot welding(refill FSSW)were compared and analyzed.Results show that the static compression load of t...The static and fatigue properties of 7B04 aluminum alloy structures connected by riveting and refill friction stir spot welding(refill FSSW)were compared and analyzed.Results show that the static compression load of the typical structure connected by riveting and refill FSSW fluctuated in the range of 117-124 kN,and the shear load was in the range of 89-95 kN.Welds spacing had a small influence on the static load of the structures joined by refill FSSW.However,the fatigue life of riveted structures was lower than that joined by refill FSSW.For the welded structure,the heterogeneous microstructures of the welded joint led to the uneven microhardness,and the hook at the lap interface bent upwards at the same time.These factors made the welded structures during the fatigue test failure along the path of sleeve moving.展开更多
基金Project(5157406)supported by the National Natural Science Foundation of China
文摘The effects of the direct current （DC） on the evolutions of hardness and morphology of the secondary phases in 7B04 aluminum alloy homogenized at 380？465 ℃ for 2 h were investigated in detail by electric conductivity measurement, hardness test, X-ray diffraction analysis, field emission scanning electron microscopy and energy dispersive spectrometry. The results show that with increasing temperature from 380 to 465 ℃, the electric conductivity of normal homogenized sample decreases from 34.9%IACS to 28.7%IACS, the hardness increases from HV 96 to HV 146, and the area fraction of secondary phase reduces from 4.5% to 1.89%. While, DC homogenized sample has a higher hardness, a lower electric conductivity and a smaller area fraction of secondary phases at the same temperature. The DC enhances the homogenization process by promoting the diffusibility of the solute atoms and the mobility of vacancy.
基金the National High-Tech Research Development Program of China (No. 2003AA331100).
文摘The effects of the two-step ageing parameters （temperature and time） on the mechanical properties and electrical conductivity of 7B04 （A1-Zn-Mg-Cu） pre-stretched thick plates were studied. The results reveal that the initial T1 ageing contributes a major increase of the tensile strength, and the 0.2% proof stress value reaches 482 MPa after ageing for 7 h at 115℃. Behavioral differences in the tensile properties of the alloy after the two-step ageing treatment were less with the first-step ageing at 115~C for different time periods （7, 14, and 21 h）. The effects of the second ageing parameters on the properties and microstructure of the 7B04 alloy were remarkable. TEM analysis of the samples aged at Temper I （7 h at 115℃ ＋ 12 h at 160℃） and Temper II （7 h at 115℃ ＋ 16 h at 165℃） indicates that two kinds of phases, i.e. 11＇ and 11 phases, precipitate from the matrix and efficiently improve the tensile strength of the alloy, and the grain boundary precipitates are coarse and discrete. There are obvious precipitate free zones （PFZs） along the grain boundary in the microstructure of the alloy after the two-step ageing treatment.
文摘AIM： To explore the propriety of providing hepatitis B virus （HBV） genotypes F and H with two distinct genotypes. METHODS： Eleven HBV isolates of genotype F （HBV/F） were recovered from patients living in San Francisco, Japan, Panama, and Venezuela, and their full-length sequences were determined. Phylogenetic analysis was carded out among them along with HBV isolates previously reported. RESULTS： Seven of them clustered with reported HBV/F Isolates in the phylogenetic tree constructed on the entire genomic sequence. The remaining four flocked on another branch along with three HBV isolates formerly reported as genotype H. These seven HBV isolates, including the four in this study and the three reported, had a sequence divergence of 7.3-9.5% from the other HBV/F isolates, and differed by 〉13.7% from HBV isolates of the other six genotypes （A-E and G）. Based on a marked genomic divergence, falling just short of 〉8% separating the seven genotypes, these seven HBV/F isolates were classified into F2 subtype and the former seven into F1 subtype provisionally. In a pairwise comparison of the S-gene sequences among the 7 HBV/F2 isolates and against 47 HBV/F1 isolates as well as 136 representing the other six genotypes （A-E and G）, two clusters separated by distinct genetic distances emerged.CONCLUSION： Based on these analyses, dassifying HBV/ F isolates into two subtypes （F1 and F2） would be more appropriate than providing them with two distinct genotypes （F and H）.
基金Project(MKPT-2004-17ZD) supported by the National 10th Five-Year Plan of China
文摘The effects of homogenization treatment on microstructure, overburnt temperature and hot rolling plasticity of high strength 7B04 aluminium alloy were investigated. Under the condition of homogenization at 470 ℃, the starting melting temperature of the primary eutectics in ingot of non-equilibium solidified 7B04 alloy is 478 ℃. Using two-step homogenization processing at ultra-high temperature which comprises heating the ingots to 470 ℃ at 10 ℃/ h and holding for 64 h, and then heating to 500 ℃ at 1 ℃ /h and holding for 10 h, the ingots of 7B04 aluminium alloy could safely pass the sensitive overburnt zone between 480 ℃ and 495 ℃, and the ordinary burnt phenomena of the ingots between 480 ℃ and 495 ℃ does not occur because the excess low-melting point eutectic phases in the as-cast alloy dissolve into the matrix during the two-step homogenization processing. Consequently, the hot rolling plasticity of ingot of 7B04 aluminium alloy is greatly improved.
基金Project(2003AA331100) supported by the Commission of Science Technology and Industry for National Defence, China
文摘The evolution of the microstructure and phases of the direct chill semicontinuous casting ingot of 7B04 super-high strength aluminum alloy during homogenization treatment was studied with metallographic analysis, scanning electron microscopy(SEM), energy spectroscopy and differential scanning calorimetry(DSC). The results show that a considerable amount of non-equilibrium eutectics containing Al, Zn, Cu and Mg exist in the direct chill semicontinuous casting ingot of 7B04 super-high strength aluminum alloy, and their melting point is 478 ℃. During homogenization treatment at 470 ℃, these eutectics dissolve into the matrix partly, coarsen and also transform into Al2CuMg phase whose equilibrium melting point is 490 ℃ in the alloy. Moreover, the homogenization treatment at 470 ℃ for 72 h results in the disappearance of the non-equilibrium eutectics though Al2CuMg phase can not dissolve completely.
文摘Objective To investigate the quantities of bone marrow CD5+ B lymphocytes in the patients with autoimmune hemocytopenia and the relationship between quantities of CD5+ B lymphocytes and clinical or laboratorial parameters. Methods Quantities of CD5+ B lymphocytes in the bone marrow of 14 patients with autoimmune hemolytic anemia (AIHA) or Evans syndrome, 22 immunorelated pancytopenia (IRP) patients, and 10 normal controls were assayed by flow cytometry. The correlation between their clinical or laboratorial parameters and CD5+ B lymphocytes was analyzed. Results The quantity of CD5+ B lymphocytes of AIHA/Evans syndrome (34.64%±19.81%) or IRP patients (35.81%±16.83%) was significantly higher than that of normal controls (12.00%±1.97%, P<0.05). However, there was no significant difference between AIHA/Evans syndrome and IRP patients (P>0.05). In all hemocytopenic patients, the quantity of bone marrow CD5+ B lymphocytes showed significantly negative correlation with serum complement C3 level (r=-0.416, P<0.05). In the patients with AIHA/Evans syndrome, the quantity of bone marrow CD5+ B lymphocytes showed significantly positive correlation with serum indirect bilirubin level (r=1.00, P<0.05). In Evans syndrome patients, the quantity of CD5+ B lymphocytes in bone marrow showed significantly positive correlation with platelet-associated immunoglobulin G (r=0.761, P<0.05) and platelet-associated immunoglobulin M (r=0.925, P<0.05). The quantity of CD5+ B lymphocytes in bone marrow of all hemocytopenic patients showed significantly negative correlation with treatment response (tau-b=-0.289, P<0.05), but had no correlation with colony forming unit-erythroid (r=-0.205, P>0.05) or colony forming unit-granulocyte-macrophage colonies (r=-0.214, P>0.05). Conclusions The quantity of bone marrow CD5+ B lymphocytes in the patients with autoimmune hemocytopenia significantly increases and is correlated with disease severity and clinical response, which suggest that CD5+ B lymphocytes might play an important role in the pathogenesis of autoimmune hemocytopenia.
基金Supported by the Fundamental Research Funds for the Central Universities(2042024YXB009 to X.C.)Special Foundation for knowledge innovation of Wuhan Science and Technology Innovation Bureau(2023020201020510 to X.C.).
文摘BACKGROUND Immunotherapy presents both promises and challenges in treating hepatocellular carcinoma(HCC)due to its complex immunological microenvironment.The role of B cells,a key part of the immune system,remains uncertain in HCC.AIM To identify B-cell-specific signatures and reveal novel immunophenotyping and therapeutic targets for HCC.METHODS Using the Tumor Immune Single-cell Hub 2 database,we identified B-cell-related genes(BRGs)in HCC.Gene enrichment analysis was performed to explore the possible collaboration between B cells and T cells in HCC.We conducted univariate Cox regression analysis using The Cancer Genome Atlas liver HCC collection dataset to find BRGs linked to HCC prognosis.Subsequently,least absolute shrinkage and selection operator regression was utilized to develop a prognostic model with 11 BRGs.The model was validated using the International Cancer Genome Consortium dataset and GSE76427.RESULTS The risk score derived from the prognostic model emerged as an independent prognostic factor for HCC.Analysis of the immune microenvironment and cell infiltration revealed the immune status of various risk groups,supporting the cooperation of B and T cells in suppressing HCC.The BRGs model identified new molecular subtypes of HCC,each with distinct immune characteristics.Drug sensitivity analysis identified targeted drugs effective for each HCC subtype,enabling precision therapy and guiding clinical decisions.CONCLUSION We clarified the role of B cells in HCC and propose that the BRGs model offers promising targets for personalized immunotherapy.
文摘The static and fatigue properties of 7B04 aluminum alloy structures connected by riveting and refill friction stir spot welding(refill FSSW)were compared and analyzed.Results show that the static compression load of the typical structure connected by riveting and refill FSSW fluctuated in the range of 117-124 kN,and the shear load was in the range of 89-95 kN.Welds spacing had a small influence on the static load of the structures joined by refill FSSW.However,the fatigue life of riveted structures was lower than that joined by refill FSSW.For the welded structure,the heterogeneous microstructures of the welded joint led to the uneven microhardness,and the hook at the lap interface bent upwards at the same time.These factors made the welded structures during the fatigue test failure along the path of sleeve moving.
