Organic acid content is one of the most important factors influencing fruit flavors.The predominant organic acid in most pear cultivars is malic acid,but the mechanism controlling its accumulation remains unclear.In t...Organic acid content is one of the most important factors influencing fruit flavors.The predominant organic acid in most pear cultivars is malic acid,but the mechanism controlling its accumulation remains unclear.In this study,by comparing gene expression levels and organic acid contents,we found that the expression of PbPH5,which encodes a P_(3A)-ATPase,is highly correlated with malic acid accumulation in four different pear species,with correlation coefficients of 0.932**,0.656*,0.900**,and 0.518*(*,P<0.05;**,P<0.01)for Pyrus bretschneideri Rehd.,P.communis Linn.,P.pyrifolia Nakai.,and P.ussuriensis Maxim.,respectively.Moreover,the overexpression of PbPH5 in pear significantly increased the malic acid content.In contrast,silencing PbPH5 via RNA interference significantly decreased both its transcript level and the pear fruit malic acid content.A subcellular localization analysis indicated that PbPH5 is located in the tonoplast.Additionally,a phylogenetic analysis indicated that PbPH5 is a PH5 homolog gene that is clustered with the Petunia hybrida,Malus domestica,and Citrus reticulata genes.Considered together,these findings suggest that PbPH5 is a functionally conserved gene.Furthermore,the accumulation of malic acid in pear fruit is at least partly related to changes in the PbPH5 transcription levels.展开更多
The global climate change and ocean acidification brought about by the anthropogenic release of carbon dioxide gas into the air is considered one of the greatest problems facing marine life.In this research,the intera...The global climate change and ocean acidification brought about by the anthropogenic release of carbon dioxide gas into the air is considered one of the greatest problems facing marine life.In this research,the interactions between two species of fish(the gold mollies and tiger barb)were investigated under two different environmental conditions,an elevated temperature of 28°C and a low pH of 5 and a normal pH of 7 and a normal temperature of 24°C.The mollies at pH 7 and a temperature of 24°C exhibited scary interactions with the tiger barb.They were scared and ran fast away from the tiger barb.At the same time,the mollies at pH 5 and a temperature of 28°C interacted normally as though both species were one species showing behavioral changes due to these two stressors(pH 5 and elevated temperature 28°C).This could be the only research that has addressed how the kinematics and swimming interactions of two species of fish changed in response to elevated temperature and low pH.展开更多
This work investigated the gradient microstructure evolution and tensile property of LPBF fabricated 15-5 precipitation hardening stainless steel in post-process direct ageing(DA)and solution treating&ageing(STA)....This work investigated the gradient microstructure evolution and tensile property of LPBF fabricated 15-5 precipitation hardening stainless steel in post-process direct ageing(DA)and solution treating&ageing(STA).The varied microstructures for austenite and small-sized oxide inclusions at different sample heights in the as-built(AB)condition was generally preserved after DA treatment.However,austenite was almost disappeared,and oxide particle grew significantly after the STA treatment.As a result,the tensile property differences in sample top and bottom for AB and DA conditions did not occur in the STA samples.For the influence of post-process heat treatment,the STA condition had the highest yield strength due to the highest volume fraction of nano-sized Cu precipitates.However,the DA specimen had the highest ultimate tensile strength and elongation owing to the considerable amount of austenite phase and associated transformation induced plasticity effect.展开更多
基金funded by the National Key Research and Development Program of China (2019YFD1001400)the National Natural Science Foundation of China (31601715)
文摘Organic acid content is one of the most important factors influencing fruit flavors.The predominant organic acid in most pear cultivars is malic acid,but the mechanism controlling its accumulation remains unclear.In this study,by comparing gene expression levels and organic acid contents,we found that the expression of PbPH5,which encodes a P_(3A)-ATPase,is highly correlated with malic acid accumulation in four different pear species,with correlation coefficients of 0.932**,0.656*,0.900**,and 0.518*(*,P<0.05;**,P<0.01)for Pyrus bretschneideri Rehd.,P.communis Linn.,P.pyrifolia Nakai.,and P.ussuriensis Maxim.,respectively.Moreover,the overexpression of PbPH5 in pear significantly increased the malic acid content.In contrast,silencing PbPH5 via RNA interference significantly decreased both its transcript level and the pear fruit malic acid content.A subcellular localization analysis indicated that PbPH5 is located in the tonoplast.Additionally,a phylogenetic analysis indicated that PbPH5 is a PH5 homolog gene that is clustered with the Petunia hybrida,Malus domestica,and Citrus reticulata genes.Considered together,these findings suggest that PbPH5 is a functionally conserved gene.Furthermore,the accumulation of malic acid in pear fruit is at least partly related to changes in the PbPH5 transcription levels.
文摘The global climate change and ocean acidification brought about by the anthropogenic release of carbon dioxide gas into the air is considered one of the greatest problems facing marine life.In this research,the interactions between two species of fish(the gold mollies and tiger barb)were investigated under two different environmental conditions,an elevated temperature of 28°C and a low pH of 5 and a normal pH of 7 and a normal temperature of 24°C.The mollies at pH 7 and a temperature of 24°C exhibited scary interactions with the tiger barb.They were scared and ran fast away from the tiger barb.At the same time,the mollies at pH 5 and a temperature of 28°C interacted normally as though both species were one species showing behavioral changes due to these two stressors(pH 5 and elevated temperature 28°C).This could be the only research that has addressed how the kinematics and swimming interactions of two species of fish changed in response to elevated temperature and low pH.
基金Sheng Cao thanks the support from the National Natural Science Foundation of China(No.52204391)the Special Fund Project for Science and Technology Innovation Strategy of Guangdong Province(Nos.STKJ202209021 and STKJ2023040)+1 种基金the Characteristic Innovation Project(Natural Science)for Regular University in Guangdong Province(No.2022KTSCX038)the Shantou University Research Foundation for Talents(No.NTF21013).
文摘This work investigated the gradient microstructure evolution and tensile property of LPBF fabricated 15-5 precipitation hardening stainless steel in post-process direct ageing(DA)and solution treating&ageing(STA).The varied microstructures for austenite and small-sized oxide inclusions at different sample heights in the as-built(AB)condition was generally preserved after DA treatment.However,austenite was almost disappeared,and oxide particle grew significantly after the STA treatment.As a result,the tensile property differences in sample top and bottom for AB and DA conditions did not occur in the STA samples.For the influence of post-process heat treatment,the STA condition had the highest yield strength due to the highest volume fraction of nano-sized Cu precipitates.However,the DA specimen had the highest ultimate tensile strength and elongation owing to the considerable amount of austenite phase and associated transformation induced plasticity effect.
