The Kyushu–Palau Ridge(KPR),an anti-S-shaped submarine highland at the center of the Philippine Sea Plate(PSP),is considered the residual arc of the Izu–Bonin–Mariana Island Arc,which retains key information about ...The Kyushu–Palau Ridge(KPR),an anti-S-shaped submarine highland at the center of the Philippine Sea Plate(PSP),is considered the residual arc of the Izu–Bonin–Mariana Island Arc,which retains key information about the cessation of the Western Philippine Basin(WPB)expansion and the Parece Vela Basin(PVB)breakup.Herein,using the new generation of satellite altimetry gravity data,high-precision seafloor topography data,and newly acquired ship-borne gravity data,the topographic and gravity characteristics of the KPR mid-southern section and adjacent region are depicted.The distribution characteristics of the faults were delineated using the normalized vertical derivative–total horizontal derivative method(NVDR-THDR)and the minimum curvature potential field separation method.The Moho depth and crustal thickness were inverted using the rapid inversion method for a double-interface model with depth constraints.Based on these results,the crust structure features in the KPR mid-southern section,and the“triangular”structure geological significance where the KPR and Central Basin Rift(CBR)of the WPB intersect are interpreted.The KPR crustal thickness is approximately 6–16 km,with a distinct discontinuity that is slightly thicker than the normal oceanic crust.The KPR mid-southern section crust structure was divided into four segments(S1–S4)from north to south,formed by the CBR eastward extension joint action and clockwise rotation of the PVB expansion axis and the Mindanao fault zone blocking effect.展开更多
To the Editor:Advanced carbohydrate counting(CC)is a recommended dietary strategy and necessary nutritional knowledge for individuals with type 1 diabetes mellitus(T1DM).^([1])Evidence supports the positive effects of...To the Editor:Advanced carbohydrate counting(CC)is a recommended dietary strategy and necessary nutritional knowledge for individuals with type 1 diabetes mellitus(T1DM).^([1])Evidence supports the positive effects of advanced CC on glucose control,quality of life,and food flexibility.^([2])However,the education and awareness of advanced CC are far from ideal for T1DM patients and even healthcare professionals.^([3])Accordingly,a measure for T1DM patients that quantifies their understanding of such nutrition knowledge would be essential for tailored care.展开更多
HIV-1 Rev is an accessory protein that plays a key role in nuclear exportation,stabilization,and translation of the viral mRNAs.Rev of HIV-1 clade BC often shows a truncation of 16 AAs due to a premature stop codon at...HIV-1 Rev is an accessory protein that plays a key role in nuclear exportation,stabilization,and translation of the viral mRNAs.Rev of HIV-1 clade BC often shows a truncation of 16 AAs due to a premature stop codon at residue 101.This stop codon presents the highest frequency in clade BC and the lowest frequency in clade B.In order to discover the potential biological effect of this truncation on Rev activity and virus replication of clade BC,we constructed Rev expression vectors of clade BC with or without 16 AAs within C-terminal separately,and replaced the stop codon by Q in a CRF07_BC infectious clone.We found that 16 AAs truncation had no effect on expression and activity of Rev in clade BC.Also,the mutation from the stop codon to Q had no effect on virus replication of clade BC.Next,to investigate the effect of this truncation on Rev activity and replication capacity of clade B,Rev expression vectors of clade B carrying or lacking 16 AAs in C-terminal were constructed respectively,and residue Q at position 101 within Rev was substituted by the stop codon in a clade B infectious clone.It was found that 16 AAs truncation significantly down-regulated Rev expression and impaired clade B Rev activity.Furthermore,a Q-to-stop codon substitution within Rev significantly reduced viral replication fitness of clade B.These results indicate that the premature stop codon at residue 101 within Rev exerts diverse impact on viral replication among different HIV-1 clades.展开更多
Chemical looping reforming of methane is a novel and effective approach to convert methane to syngas,in which oxygen transfer is achieved by a redox material.Although lots of efforts have been made to develop high-per...Chemical looping reforming of methane is a novel and effective approach to convert methane to syngas,in which oxygen transfer is achieved by a redox material.Although lots of efforts have been made to develop high-performance redox materials,a few studies have focused on the redox kinetics.In this work,the kinetics of SrFeO_(3−δ)–CaO∙MnO nanocomposite reduction by methane was investigated both on a thermo-gravimetric analyzer and in a packed-bed microreactor.During the methane reduction,combustion occurs before the partial oxidation and there exists a transition between them.The weight loss due to combustion increases,but the transition region becomes less inconspicuous as the reduction temperature increased.The weight loss associated with the partial oxidation is much larger than that with combustion.The rate of weight loss related to the partial oxidation is well fitted by the Avrami–Erofeyev equation with n=3(A3 model)with an activation energy of 59.8 kJ∙mol^(‒1).The rate law for the partial oxidation includes a solid conversion term whose expression is given by the A3 model and a methane pressure-dependent term represented by a power law.The partial oxidation is half order with respect to methane pressure.The proposed rate law could well predict the reduction kinetics;thus,it may be used to design and/or analyze a chemical looping reforming reactor.展开更多
基金‘Research on Deep Structural Differences between Potential Oil-rich Depressions in Offshore basins of China Sea’from the scientific and technological project of CNOOC Research Institute Co.,Ltd.,under contract No.CCL2021RCPS0167KQN‘Resource Potential,Accumulation Mechanism and Breakthrough Direction of Potential Oil-rich Depressions in Offshore China Sea’,under contract No.220226220101+1 种基金the Project of China Geological Survey under contract No.DD20191003the National Natural Science Foundation of Shandong Province of China under contract No.ZR2022MD047。
文摘The Kyushu–Palau Ridge(KPR),an anti-S-shaped submarine highland at the center of the Philippine Sea Plate(PSP),is considered the residual arc of the Izu–Bonin–Mariana Island Arc,which retains key information about the cessation of the Western Philippine Basin(WPB)expansion and the Parece Vela Basin(PVB)breakup.Herein,using the new generation of satellite altimetry gravity data,high-precision seafloor topography data,and newly acquired ship-borne gravity data,the topographic and gravity characteristics of the KPR mid-southern section and adjacent region are depicted.The distribution characteristics of the faults were delineated using the normalized vertical derivative–total horizontal derivative method(NVDR-THDR)and the minimum curvature potential field separation method.The Moho depth and crustal thickness were inverted using the rapid inversion method for a double-interface model with depth constraints.Based on these results,the crust structure features in the KPR mid-southern section,and the“triangular”structure geological significance where the KPR and Central Basin Rift(CBR)of the WPB intersect are interpreted.The KPR crustal thickness is approximately 6–16 km,with a distinct discontinuity that is slightly thicker than the normal oceanic crust.The KPR mid-southern section crust structure was divided into four segments(S1–S4)from north to south,formed by the CBR eastward extension joint action and clockwise rotation of the PVB expansion axis and the Mindanao fault zone blocking effect.
基金supported by the National Key Research and Development Program of China(No.2022YFC2010102)the Science and Technology Innovation Program of Hunan Province(No.2020RC4044)the Natural Science Foundation of China(No.82070812).
文摘To the Editor:Advanced carbohydrate counting(CC)is a recommended dietary strategy and necessary nutritional knowledge for individuals with type 1 diabetes mellitus(T1DM).^([1])Evidence supports the positive effects of advanced CC on glucose control,quality of life,and food flexibility.^([2])However,the education and awareness of advanced CC are far from ideal for T1DM patients and even healthcare professionals.^([3])Accordingly,a measure for T1DM patients that quantifies their understanding of such nutrition knowledge would be essential for tailored care.
文摘HIV-1 Rev is an accessory protein that plays a key role in nuclear exportation,stabilization,and translation of the viral mRNAs.Rev of HIV-1 clade BC often shows a truncation of 16 AAs due to a premature stop codon at residue 101.This stop codon presents the highest frequency in clade BC and the lowest frequency in clade B.In order to discover the potential biological effect of this truncation on Rev activity and virus replication of clade BC,we constructed Rev expression vectors of clade BC with or without 16 AAs within C-terminal separately,and replaced the stop codon by Q in a CRF07_BC infectious clone.We found that 16 AAs truncation had no effect on expression and activity of Rev in clade BC.Also,the mutation from the stop codon to Q had no effect on virus replication of clade BC.Next,to investigate the effect of this truncation on Rev activity and replication capacity of clade B,Rev expression vectors of clade B carrying or lacking 16 AAs in C-terminal were constructed respectively,and residue Q at position 101 within Rev was substituted by the stop codon in a clade B infectious clone.It was found that 16 AAs truncation significantly down-regulated Rev expression and impaired clade B Rev activity.Furthermore,a Q-to-stop codon substitution within Rev significantly reduced viral replication fitness of clade B.These results indicate that the premature stop codon at residue 101 within Rev exerts diverse impact on viral replication among different HIV-1 clades.
基金This work was financially supported by the National Natural Science Foundation of China(Grant No.21978230)Shaanxi Creative Talents Promotion Plan−Technological Innovation Team(Grant No.2019TD-039).
文摘Chemical looping reforming of methane is a novel and effective approach to convert methane to syngas,in which oxygen transfer is achieved by a redox material.Although lots of efforts have been made to develop high-performance redox materials,a few studies have focused on the redox kinetics.In this work,the kinetics of SrFeO_(3−δ)–CaO∙MnO nanocomposite reduction by methane was investigated both on a thermo-gravimetric analyzer and in a packed-bed microreactor.During the methane reduction,combustion occurs before the partial oxidation and there exists a transition between them.The weight loss due to combustion increases,but the transition region becomes less inconspicuous as the reduction temperature increased.The weight loss associated with the partial oxidation is much larger than that with combustion.The rate of weight loss related to the partial oxidation is well fitted by the Avrami–Erofeyev equation with n=3(A3 model)with an activation energy of 59.8 kJ∙mol^(‒1).The rate law for the partial oxidation includes a solid conversion term whose expression is given by the A3 model and a methane pressure-dependent term represented by a power law.The partial oxidation is half order with respect to methane pressure.The proposed rate law could well predict the reduction kinetics;thus,it may be used to design and/or analyze a chemical looping reforming reactor.