Background： Heat stress has resulted in great losses in poultry production. To address this issue, we systematically analyzed chicken hypothalamus transcriptome responses to thermal stress using a 44 k chicken Agilen...Background： Heat stress has resulted in great losses in poultry production. To address this issue, we systematically analyzed chicken hypothalamus transcriptome responses to thermal stress using a 44 k chicken Agilent microarray, Methods： Hypothalamus samples were collected from a control group reared at 25℃, a heat-stress group treated at 34℃ for 24 h, and a temperature-recovery group reared at 25℃ for 24 h following a heat-stress treatment. We compared the expression profiles between each pair of the three groups using microarray data. Results： A total of 1,967 probe sets were found to be differentially expressed in the three comparisons with P 〈 0.05 and a fold change （FC） higher than 1.5, and the genes were mainly involved in self-regulation and compensation required to maintain homeostasis. Consistent expression results were found for 11 selected genes by quantitative real-time PCR. Thirty-eight interesting differential expression genes were found from GO term annotation and those genes were related to meat quality, growth, and crucial enzymes. Using these genes for genetic network analysis, we obtained three genetic networks. Moreover, the transcripts of heat-shock protein, including Hsp 40 and Hsp 90, were significantly altered in response to thermal stress. Conclusions： This study provides a broader understanding of molecular mechanisms underlying stress response in chickens and discovery of novel genes that are regulated in a specific thermal-stress manner.展开更多
LaNiO3 thin films with different La/Ni ratios were deposited on Si substrates by sol-gel process. The electrical resistivities of LaNixO3＋δfilms with different La/Ni ratios were measured by four-probe method.LaNi（0...LaNiO3 thin films with different La/Ni ratios were deposited on Si substrates by sol-gel process. The electrical resistivities of LaNixO3＋δfilms with different La/Ni ratios were measured by four-probe method.LaNi（0.95）O3＋δthin film has the lowest resistivity. First-principle calculations show that LaNi（0.95）O3＋δhas the largest Ni-O-Ni bond angle and the shortest Ni-O bond length, which means LaNi（0.95）O3＋δhas the strongest metallic property, hence, the electrical resistivity is the lowest. Au/PZT（PbZr（0.52）Ti（0.48）O3）/LaNixO3＋δand Au/PZT/Pt ferroelectric capacitors were fabricated to evaluate LaNixO3＋δas a bottom electrode. It is shown that fatigue properties of PZT films can be significantly improved by using LaNixO3＋δinstead of Pt as the bottom electrode. The Ⅰ-Ⅴ test results of PZT films show that LaNi（0.95）O3＋δas bottom electrode can reduce the threshold voltages of PZT films, suggesting that La/Ni ratio in LaNixO3＋δas a large influence on the film properties.展开更多
Characterized by the quasi-conically symmetric flow field,κshock wave system,and highly three-dimensional separation structures,the swept shock-wave/boundarylayer interaction(SBLI)induced by sharp fins is one of the ...Characterized by the quasi-conically symmetric flow field,κshock wave system,and highly three-dimensional separation structures,the swept shock-wave/boundarylayer interaction(SBLI)induced by sharp fins is one of the most important phenomena in supersonic flights.An aerothermoelastic analysis is conducted on the interactions between thin-walled panels and swept SBLIs.The results of rigid wall condition,aeroelastic analysis and aerothermoelastic analysis are compared to highlight the significant influence of fluid-thermal-structural interactions on the structure and the flow field of swept SBLIs.The results show that in the aeroelastic analysis,for the material applied to the panel,although a dynamic structural response is observed,the deformation is minor and has a limited influence on the flow field.However,in the aerothermoelastic analysis,the consideration of aerodynamic heating has a significant impact on the structural response and the flow field.The deformation is an order of magnitude larger than that in the aeroelastic analysis with high vibration frequency and various main frequencies at different locations.As a result,the flow field is no longer quasi-conically symmetric.Theλshock wave system and separation structures are completely disrupted by multiple shock and expansion waves induced by the large structural deformation and become much more complex with highly three-dimensional features.This research highlights the significance of investigations on complex three-dimensional aerothermoelastic problems for supersonic flight vehicles.展开更多
基金financially supported by Beijing innovation team attached to poultry industry technology system(CARS-PSTP)
文摘Background： Heat stress has resulted in great losses in poultry production. To address this issue, we systematically analyzed chicken hypothalamus transcriptome responses to thermal stress using a 44 k chicken Agilent microarray, Methods： Hypothalamus samples were collected from a control group reared at 25℃, a heat-stress group treated at 34℃ for 24 h, and a temperature-recovery group reared at 25℃ for 24 h following a heat-stress treatment. We compared the expression profiles between each pair of the three groups using microarray data. Results： A total of 1,967 probe sets were found to be differentially expressed in the three comparisons with P 〈 0.05 and a fold change （FC） higher than 1.5, and the genes were mainly involved in self-regulation and compensation required to maintain homeostasis. Consistent expression results were found for 11 selected genes by quantitative real-time PCR. Thirty-eight interesting differential expression genes were found from GO term annotation and those genes were related to meat quality, growth, and crucial enzymes. Using these genes for genetic network analysis, we obtained three genetic networks. Moreover, the transcripts of heat-shock protein, including Hsp 40 and Hsp 90, were significantly altered in response to thermal stress. Conclusions： This study provides a broader understanding of molecular mechanisms underlying stress response in chickens and discovery of novel genes that are regulated in a specific thermal-stress manner.
基金support from the Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education (Tianjin University)
文摘LaNiO3 thin films with different La/Ni ratios were deposited on Si substrates by sol-gel process. The electrical resistivities of LaNixO3＋δfilms with different La/Ni ratios were measured by four-probe method.LaNi（0.95）O3＋δthin film has the lowest resistivity. First-principle calculations show that LaNi（0.95）O3＋δhas the largest Ni-O-Ni bond angle and the shortest Ni-O bond length, which means LaNi（0.95）O3＋δhas the strongest metallic property, hence, the electrical resistivity is the lowest. Au/PZT（PbZr（0.52）Ti（0.48）O3）/LaNixO3＋δand Au/PZT/Pt ferroelectric capacitors were fabricated to evaluate LaNixO3＋δas a bottom electrode. It is shown that fatigue properties of PZT films can be significantly improved by using LaNixO3＋δinstead of Pt as the bottom electrode. The Ⅰ-Ⅴ test results of PZT films show that LaNi（0.95）O3＋δas bottom electrode can reduce the threshold voltages of PZT films, suggesting that La/Ni ratio in LaNixO3＋δas a large influence on the film properties.
基金supported by the National Natural Science Foundation of China(Grant No.12302229,and No.12272354)the Youth Talent Support Program of Henan Province(Grant No.2025HYTP025)+1 种基金the Postdoctoral Fellowship Program of CPSF(Grant No.GZC20232400)the Key Research Project Plan of Higher Education Institutions in Henan Province(Grant No.25A590004)。
文摘Characterized by the quasi-conically symmetric flow field,κshock wave system,and highly three-dimensional separation structures,the swept shock-wave/boundarylayer interaction(SBLI)induced by sharp fins is one of the most important phenomena in supersonic flights.An aerothermoelastic analysis is conducted on the interactions between thin-walled panels and swept SBLIs.The results of rigid wall condition,aeroelastic analysis and aerothermoelastic analysis are compared to highlight the significant influence of fluid-thermal-structural interactions on the structure and the flow field of swept SBLIs.The results show that in the aeroelastic analysis,for the material applied to the panel,although a dynamic structural response is observed,the deformation is minor and has a limited influence on the flow field.However,in the aerothermoelastic analysis,the consideration of aerodynamic heating has a significant impact on the structural response and the flow field.The deformation is an order of magnitude larger than that in the aeroelastic analysis with high vibration frequency and various main frequencies at different locations.As a result,the flow field is no longer quasi-conically symmetric.Theλshock wave system and separation structures are completely disrupted by multiple shock and expansion waves induced by the large structural deformation and become much more complex with highly three-dimensional features.This research highlights the significance of investigations on complex three-dimensional aerothermoelastic problems for supersonic flight vehicles.
