Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigat...Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties.展开更多
BACKGROUND Skin is the largest organ in the human body and plays crucial roles in human health.Efficient and rapid healing of burn wounds is of great significance.While stem cell therapies have offered potential metho...BACKGROUND Skin is the largest organ in the human body and plays crucial roles in human health.Efficient and rapid healing of burn wounds is of great significance.While stem cell therapies have offered potential methods to treat burn wounds,relatively few have had success in clinical practice.AIM To investigate the effect of the combined application of collagen III and adiposederived stem cells(ASCs)on vascular regeneration in skin wound healing.METHODS Burn wounds were created in 18 adult male Sprague-Dawley rats,and they were randomly divided into two groups.In the treatment group,each rat was injected with 4×10^(6) Zs-Green-labeled autologous ASCs suspended in collagen III.In the control group,each rat was injected with collagen III.Each rat received six injections.Images of the wounds were acquired every 3 days.RESULTS Multiple injections of autologous ASCs improved wound closure rate more efficiently compared to the control group.Moreover,autologous ASCs do not survive long-term during the skin wound healing process.CONCLUSION This study demonstrated that multiple injections of autologous ASCs combined with collagen III accelerated burn wound healing by increasing collagen deposition and improving angiogenesis.展开更多
Objective:To observe the effect of co-culture cytokine-induced killer cells(CIK) and homologous dendritic cells(DC) on the proliferative activity and phenotype change of the DCCIK cell and the cell killing activity of...Objective:To observe the effect of co-culture cytokine-induced killer cells(CIK) and homologous dendritic cells(DC) on the proliferative activity and phenotype change of the DCCIK cell and the cell killing activity of leukemia HL-60.Methods:50 mL cord blood sample was obtained from infants delivered by full term healthy woman and the cord blood mononuclear cells were isolated by density gradient centrifugal ion.Non-adherent cells were collectedfor the induction culture of CIK.adherent cells were differentiated into mature DC;cultured mature DC was mixed with and CIK in the proportion of 1:5 for 12 d.killing activity of DC-CIK co-cultured cell on leukemia HL-60 was detected by MTT assay.Results:Compared with CIKs.the cocultured DC-CIKs presented a markedly higher proliferation and killing activity.Conclusions:Co-culture of DC-CIK cells led to a significant increase of the proliferation and cytotoxicity of CIK.展开更多
To investigate the tensile deformation behavior of high strength anti-seismic steel with multi-phase microstructure,tensile tests with strains of 0.05,0.12 and 0.22 were performed at room temperature.Microstructure of...To investigate the tensile deformation behavior of high strength anti-seismic steel with multi-phase microstructure,tensile tests with strains of 0.05,0.12 and 0.22 were performed at room temperature.Microstructure of tested steels was observed by means of optical microscopy（OM）,transmission electron microscopy（TEM）and scanning electron microscopy（SEM）.Tensile mechanical properties of tested steels were obtained,and the influence of bainite content on deformation behavior was also discussed.Meanwhile,the deformation mechanism of steel with three kinds of microstructures of bainite,pearlite and ferrite was analyzed.Results show that tested steel with high volume fraction of bainite exhibits a continuous deformation behavior,and this may be attributed to a higher bainite volume fraction and a lower mobile dislocation density.The morphology of microstructure will influence the mechanical properties of tested steels.An increasing content of bainite can improve the tensile strength,but reduce the plasticity and toughness of the tested steels.In the deformation process of 0.039 Nb steel,the ferrite and bainite have priorities to deform,and the deformation exhibits co-deformation of all microstructures in the later stage of deformation.In the deformation process of 0.024Nb-0.032 Vsteel,the ferrite and pearlite have priorities to deform,and the deformation exhibits co-deformation of all microstructures in the later stage of deformation.展开更多
Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source rocks.Lacustrine source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organ...Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source rocks.Lacustrine source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organic carbon(TOC)content,various kerogen types,and a wide range of thermal maturity.Consequently,their hydrocarbon generation potential and resource estimation can be misinterpreted.In this study,geochemical tests,numerical analysis,hydrocarbon generation kinetics,and basin modeling were integrated to investigate the differential effects of kerogen types on the hydrocarbon generation potential of lacustrine source rocks.Optimized hydrocarbon generation and expulsion(HGE)models of different kerogen types were established quantitatively upon abundant Rock-Eval/TOC/vitrinite reflectance(R_(o))datasets.Three sets of good-excellent source rocks deposited in the fourth(Es4),third(Es3),and first(Es1)members of Paleogene Shahejie Formation,are predominantly types I-II_(1),II_(1)-II_(2),and II-III,respectively.The activation energy of types I-II_(2)kerogen is concentrated(180-230 kcal/mol),whereas that of type III kerogen is widely distributed(150-280 kcal/mol).The original hydrocarbon generation potentials of types I,II_(1),II_(2),and III kerogens are 790,510,270,and 85 mg/g TOC,respectively.The Ro values of the hydrocarbon generation threshold for type I-III source rocks gradually increase from 0.42%to 0.74%,and Ro values of the hydrocarbon expulsion threshold increase from 0.49%to 0.87%.Types I and II_(1)source rocks are characterized by earlier hydrocarbon generation,more rapid hydrocarbon expulsion,and narrower hydrocarbon generation windows than types II_(2)and III source rocks.The kerogen types also affect the HGE history and resource potential.Three types(conventional,tight,and shale oil/gas)and three levels(realistic,expected,and prospective)of hydrocarbon resources of different members in the Liaohe Western Depression are evaluated.Findings suggest that the Es3 member has considerable conventional and unconventional hydrocarbon resources.This study can quantitatively characterize the hydrocarbon generation potential of source rocks with different kerogen types,and facilitate a quick and accurate assessment of hydrocarbon resources,providing strategies for future oil and gas exploration.展开更多
The microstructural evolvement and friction performance of Cu/FeS self-lubricating composites within electric field were studied by molecular dynamics simulation.The atoms distribution and movement of the Cu/FeS compo...The microstructural evolvement and friction performance of Cu/FeS self-lubricating composites within electric field were studied by molecular dynamics simulation.The atoms distribution and movement of the Cu/FeS composite under different electric field strengths were considered.The results show that some Fe atoms and S atoms break away from the original structure and move along the electric field,but the movement of Fe atoms and S atoms is not synchronized in stronger electric field strength.Thus,the whole material system becomes chaotic and its temperature rises.The unevenly electric field force appears in the material for the nonuniform FeS distribution,so the internal stress of the composite is generated.For the internal solid lubricating phases move along the direction of the electric field to the surface of the composite,the adhesive wear and the friction coefficient reduce.The movement of the phases leaves over some voids in the composite,which induces arc wear easily.展开更多
Type Ia Supernovae(SNe Ia)are widely used as standard candles to probe the Universe.However,how these fierce explosions are produced itself is still a highly debated issue.There are mainly two popular models for SNe I...Type Ia Supernovae(SNe Ia)are widely used as standard candles to probe the Universe.However,how these fierce explosions are produced itself is still a highly debated issue.There are mainly two popular models for SNe Ia:the double-degenerate scenario and the single-degenerate scenario.The doubledegenerate scenario suggests that SNe Ia are produced by the coalescence of two degenerate white dwarfs,while the single-degenerate scenario suggests that the continuous accretion of a single degenerate white dwarf from its normal stellar companion will finally lead to a disastrous explosion when it is over-massive,resulting in an SN Ia.The rapid development of the gravitational wave astronomy sheds new light on the nature of SNe Ia.In this study,we calculate the gravitational wave emissions of double white dwarf coalescences and compare them with the sensitivities of several upcoming detectors.It is found that the gravitational wave emissions from double white dwarf mergers in the local universe are strong enough to be detected by LISA.We argue that LISA-like gravitational wave detectors sensitive in the frequency range of 0.01—0.1 Hz will be a powerful tool to test the double-degenerate model of SNe Ia,and also to probe the Universe.展开更多
Scrophularia ningpoensis has long been used in the Chinese Materia Medica for inflammation.Like other herbal medicines,S.ningpoensis collected from different localities may considerably differ in their therapeutic eff...Scrophularia ningpoensis has long been used in the Chinese Materia Medica for inflammation.Like other herbal medicines,S.ningpoensis collected from different localities may considerably differ in their therapeutic efficacy,and the one grown in Zhejiang Province is recognized as geo-authentic.However,it is difficult to confirm the geo-graphical authenticity by similar morphological characteristics.In the present study,inter-simple sequence repeat(ISSR) markers were conducted to detect S.ningpoensis from different origins.A 1 259-bp fragment amplified by primer UBC874 was found only in geo-authentic ones.By cloning and sequencing that specific band,sequence characterized amplified region(SCAR) markers were designed to distinguish geo-authentic S.ningpoensis from others.This is a rapid and easy method that can be used to identify the geographical authenticity of S.ningpoensis.展开更多
Mitochondria are cellular organelles that originate from an endosymbiotic bacterial ancestor and are primarily responsible for ATP generation via oxidative phosphorylation(OXPHOS).OXPHOS is conducted by five mitochond...Mitochondria are cellular organelles that originate from an endosymbiotic bacterial ancestor and are primarily responsible for ATP generation via oxidative phosphorylation(OXPHOS).OXPHOS is conducted by five mitochondrial respiratory complexes in the inner mitochondrial membrane.Human mitochondria possess a distinct genome,a small,circular,double-stranded DNA(mtDNA)of 16,569 base pairs.This genome encodes 37 genes.展开更多
With the increasing demand for security,building strong barrier coverage in directional sensor networks is important for effectively detecting un-authorized intrusions.In this paper,we propose an efficient scheme to f...With the increasing demand for security,building strong barrier coverage in directional sensor networks is important for effectively detecting un-authorized intrusions.In this paper,we propose an efficient scheme to form the strong barrier coverage by adding the mobile nodes one by one into the barrier.We first present the concept of target circle which determines the appropriate residence region and working direction of any candidate node to be added.Then we select the optimal relay sensor to be added into the current barrier based on its input-output ratio(barrier weight)which reflects the extension of barrier coverage.This strategy looses the demand of minimal required sensor nodes(maximal gain of each sensor)or maximal lifetime of one single barrier,leading to an augmentation of sensors to be used.Numerical simulation results show that,compared with the available schemes,the proposed method significantly reduces the minimal deploy density required to establish k-barrier,and increases the total service lifetime with a high deploy efficiency.展开更多
Aminoacyl-tRNA synthetases(aaRSs)are ubiquitously expressed,essential enzymes,synthesizing aminoacyl-tRNAs for protein synthesis.Functional defects of aaRSs frequently cause various human disorders.Human KARS encodes ...Aminoacyl-tRNA synthetases(aaRSs)are ubiquitously expressed,essential enzymes,synthesizing aminoacyl-tRNAs for protein synthesis.Functional defects of aaRSs frequently cause various human disorders.Human KARS encodes both cytosolic and mitochondrial lysyl-tRNA synthetases(LysRSs).Previously,two mutations(c.1129 G>A and c.517 T>C)were identified that led to hearing impairment;however,the underlying biochemical mechanism is unclear.In the present study,we found that the two mutations have no impact on the incorporation of LysRS into the multiple-synthetase complex in the cytosol,but affect the cytosolic LysRS level,its tertiary structure,and cytosolic tRNA aminoacylation in vitro.As for mitochondrial translation,the two mutations have little effect on the steady-state level,mitochondrial targeting,and tRNA binding affinity of mitochondrial LysRS.However,they exhibit striking differences in charging mitochondrial tRNALys,with the c.517T>C mutant being completely deficient in vitro and in vivo.We constructed two yeast genetic models,which are powerful tools to test the in vivo aminoacylation activity of KARS mutations at both the cytosolic and mitochondrial levels.Overall,our data provided biochemical insights into the potentially molecular pathological mechanism of KARS c.1129G>A and c.517T>C mutations and provided yeast genetic bases to investigate other KARS mutations in the future.展开更多
Mutations of the genes encoding aminoacyl-tRNA synthetases are highly associated with various central nervous system disorders.Recurrent mutations,including c.5A>G,p.D2G;c.1367C>T,p.S456L;c.1535G>A,p.R512Q an...Mutations of the genes encoding aminoacyl-tRNA synthetases are highly associated with various central nervous system disorders.Recurrent mutations,including c.5A>G,p.D2G;c.1367C>T,p.S456L;c.1535G>A,p.R512Q and c.1846_1847del,p.Y616Lfs*6 of RARS1 gene,which encodes two forms of human cytoplasmic arginyl-tRNA synthetase(hArgRS),are linked to Pelizaeus-Merzbacher-like disease(PMLD)with unclear pathogenesis.Among these mutations,c.5A>G is the most extensively reported mutation,leading to a p.D2G mutation in the N-terminal extension of the long-form hArgRS.Here,we showed the detrimental effects of R512Q substitution andΔC mutations on the structure and function of hArgRS,while the most frequent mutation c.5A>G,p.D2G acted in a different manner without impairing hArgRS activity.The nucleotide substitution c.5A>G reduced translation of hArgRS mRNA,and an upstream open reading frame contributed to the suppressed translation of the downstream main ORF.Taken together,our results elucidated distinct pathogenic mechanisms of various RARS1 mutations in PMLD.展开更多
The cavity quantum electrodynamics (QED) system is a promising platform for quantum optics and quantum information experiments.Its core is the strong coupling between atoms and optical cavity,which causes difficulty i...The cavity quantum electrodynamics (QED) system is a promising platform for quantum optics and quantum information experiments.Its core is the strong coupling between atoms and optical cavity,which causes difficulty in the overlap between the atoms and the antinode of optical cavity mode.Here,we use a programmable movable optical dipole trap to load a cold atomic ensemble into an optical fiber microcavity and realize the strong coupling between the atoms and the optical cavity in which the coupling strength can be improved by polarization gradient cooling and adiabatic loading.By the measurement of vacuum Rabi splitting,the coupling strength can be as high as g_(N)=2π×400 MHz,which means the effective atom number is N_(eff)=16 and the collective cooperativity is C_(N)=1466.These results show that this experimental system can be used for cold atomic ensemble and cold molecule based cavity QED research.展开更多
Dear Editor Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has become a serious emergency to global public health since its outbreak in 2019.SARS-CoV-2 is an e...Dear Editor Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has become a serious emergency to global public health since its outbreak in 2019.SARS-CoV-2 is an enveloped,positive-sense,single-strand RNA virus,belonging to the Betacoronavirus genus of the Coronaviridae family(Wu et al.,2020)including SARS-CoV,SARS-CoV-2,MERS-CoV,etc.展开更多
基金supported by the Key Research and Development Program of Hunan Province of China(No.2022NK2036)Xiangxi Prefecture Science and Technology Plan Project"School-Local Integration"Special Project(No.2022001)the scientific research project of Hunan Provincial Department of Education(No.22B0520).
文摘Background:Ampelopsis grossedentata,vine tea,which is the tea alternative beverages in China.In vine tea processing,a large amount of broken tea is produced,which has low commercial value.Methods:This study investigates the influence of different extraction methods(room temperature water extraction,boiling water extraction,ultrasonic-assisted room temperature water extraction,and ultrasonic-assisted boiling water extraction,referred to as room temperature water extraction(RE),boiling water extraction(BE),ultrasonic assistance at room temperature water extraction(URE),and ultrasonic assistance in boiling water extraction(UBE))on the yield,dihydromyricetin(DMY)content,free amino acid composition,volatile aroma components,and antioxidant properties of vine tea extracts.Results:A notable influence of extraction temperature on the yield of vine tea extracts(P<0.05),with BE yielding the highest at 43.13±0.26%,higher than that of RE(34.29±0.81%).Ultrasound-assisted extraction significantly increased the DMY content of the extracts(P<0.05),whereas DMY content in the RE extracts was 59.94±1.70%,that of URE reached 66.14±2.78%.Analysis revealed 17 amino acids,with L-serine and aspartic acid being the most abundant in the extracts,nevertheless ultrasound-assisted extraction reduced total free amino acid content.Gas chromatography-mass spectrometry analysis demonstrated an increase in the diversity and quantity of compounds in the vine tea water extracts obtained through ultrasonic-assisted extraction.Specifically,69 and 68 volatile compounds were found in URE and UBE extracts,which were higher than the number found in RE and BE extracts.In vitro,antioxidant activity assessments revealed varying antioxidant capacities among different extraction methods,with RE exhibiting the highest DPPH scavenging rate,URE leading in ABTS•+free radical scavenging,and BE demonstrating superior ferric ion reducing antioxidant activity.Conclusion:The findings suggest that extraction methods significantly influence the chemical composition and antioxidant properties of vine tea extracts.Ultrasonic-assisted extraction proved instrumental in elevating the DMY content in vine tea extracts,thereby enriching its flavor profile while maintaining its antioxidant properties.
基金Supported by the Natural Science Foundation of Hunan Province,China,No.2021JJ40638the Research Foundation of Education Bureau of Hunan Province,China,No.22B0897General Funding Project of Hunan Provincial Health Commission,China,No.202202055404.
文摘BACKGROUND Skin is the largest organ in the human body and plays crucial roles in human health.Efficient and rapid healing of burn wounds is of great significance.While stem cell therapies have offered potential methods to treat burn wounds,relatively few have had success in clinical practice.AIM To investigate the effect of the combined application of collagen III and adiposederived stem cells(ASCs)on vascular regeneration in skin wound healing.METHODS Burn wounds were created in 18 adult male Sprague-Dawley rats,and they were randomly divided into two groups.In the treatment group,each rat was injected with 4×10^(6) Zs-Green-labeled autologous ASCs suspended in collagen III.In the control group,each rat was injected with collagen III.Each rat received six injections.Images of the wounds were acquired every 3 days.RESULTS Multiple injections of autologous ASCs improved wound closure rate more efficiently compared to the control group.Moreover,autologous ASCs do not survive long-term during the skin wound healing process.CONCLUSION This study demonstrated that multiple injections of autologous ASCs combined with collagen III accelerated burn wound healing by increasing collagen deposition and improving angiogenesis.
基金supported by Health Department of Shandong Province,Science and Technology Program Fund Assistance ltem(No:2010HZ102)
文摘Objective:To observe the effect of co-culture cytokine-induced killer cells(CIK) and homologous dendritic cells(DC) on the proliferative activity and phenotype change of the DCCIK cell and the cell killing activity of leukemia HL-60.Methods:50 mL cord blood sample was obtained from infants delivered by full term healthy woman and the cord blood mononuclear cells were isolated by density gradient centrifugal ion.Non-adherent cells were collectedfor the induction culture of CIK.adherent cells were differentiated into mature DC;cultured mature DC was mixed with and CIK in the proportion of 1:5 for 12 d.killing activity of DC-CIK co-cultured cell on leukemia HL-60 was detected by MTT assay.Results:Compared with CIKs.the cocultured DC-CIKs presented a markedly higher proliferation and killing activity.Conclusions:Co-culture of DC-CIK cells led to a significant increase of the proliferation and cytotoxicity of CIK.
基金funded by National Natural Science Foundation of China(51261009)
文摘To investigate the tensile deformation behavior of high strength anti-seismic steel with multi-phase microstructure,tensile tests with strains of 0.05,0.12 and 0.22 were performed at room temperature.Microstructure of tested steels was observed by means of optical microscopy（OM）,transmission electron microscopy（TEM）and scanning electron microscopy（SEM）.Tensile mechanical properties of tested steels were obtained,and the influence of bainite content on deformation behavior was also discussed.Meanwhile,the deformation mechanism of steel with three kinds of microstructures of bainite,pearlite and ferrite was analyzed.Results show that tested steel with high volume fraction of bainite exhibits a continuous deformation behavior,and this may be attributed to a higher bainite volume fraction and a lower mobile dislocation density.The morphology of microstructure will influence the mechanical properties of tested steels.An increasing content of bainite can improve the tensile strength,but reduce the plasticity and toughness of the tested steels.In the deformation process of 0.039 Nb steel,the ferrite and bainite have priorities to deform,and the deformation exhibits co-deformation of all microstructures in the later stage of deformation.In the deformation process of 0.024Nb-0.032 Vsteel,the ferrite and pearlite have priorities to deform,and the deformation exhibits co-deformation of all microstructures in the later stage of deformation.
基金This research is supported by the Joint Fund of the National Natural Science Foundation of China(grant number U19B6003-02)the Cooperation Program of PetroChina Liaohe Oilfield Company(grant Number HX20180604)the AAPG Foundation Grants-in-Aid Program(grant number 22269437).This study has benefited considerably from PetroChina Liaohe Oilfield Company for data support.We also thank the editor and the anonymous reviewers for their professional suggestions and comments.
文摘Kerogen types exert a decisive effect on the onset and capacity of hydrocarbon generation of source rocks.Lacustrine source rocks in the Liaohe Western Depression are characterized by thick deposition,high total organic carbon(TOC)content,various kerogen types,and a wide range of thermal maturity.Consequently,their hydrocarbon generation potential and resource estimation can be misinterpreted.In this study,geochemical tests,numerical analysis,hydrocarbon generation kinetics,and basin modeling were integrated to investigate the differential effects of kerogen types on the hydrocarbon generation potential of lacustrine source rocks.Optimized hydrocarbon generation and expulsion(HGE)models of different kerogen types were established quantitatively upon abundant Rock-Eval/TOC/vitrinite reflectance(R_(o))datasets.Three sets of good-excellent source rocks deposited in the fourth(Es4),third(Es3),and first(Es1)members of Paleogene Shahejie Formation,are predominantly types I-II_(1),II_(1)-II_(2),and II-III,respectively.The activation energy of types I-II_(2)kerogen is concentrated(180-230 kcal/mol),whereas that of type III kerogen is widely distributed(150-280 kcal/mol).The original hydrocarbon generation potentials of types I,II_(1),II_(2),and III kerogens are 790,510,270,and 85 mg/g TOC,respectively.The Ro values of the hydrocarbon generation threshold for type I-III source rocks gradually increase from 0.42%to 0.74%,and Ro values of the hydrocarbon expulsion threshold increase from 0.49%to 0.87%.Types I and II_(1)source rocks are characterized by earlier hydrocarbon generation,more rapid hydrocarbon expulsion,and narrower hydrocarbon generation windows than types II_(2)and III source rocks.The kerogen types also affect the HGE history and resource potential.Three types(conventional,tight,and shale oil/gas)and three levels(realistic,expected,and prospective)of hydrocarbon resources of different members in the Liaohe Western Depression are evaluated.Findings suggest that the Es3 member has considerable conventional and unconventional hydrocarbon resources.This study can quantitatively characterize the hydrocarbon generation potential of source rocks with different kerogen types,and facilitate a quick and accurate assessment of hydrocarbon resources,providing strategies for future oil and gas exploration.
基金financially supported by the State Key Laboratory of Advanced Technologies for Comprehensive Utilization of Platinum Metals(No.SKL-SPM-201510)
文摘The microstructural evolvement and friction performance of Cu/FeS self-lubricating composites within electric field were studied by molecular dynamics simulation.The atoms distribution and movement of the Cu/FeS composite under different electric field strengths were considered.The results show that some Fe atoms and S atoms break away from the original structure and move along the electric field,but the movement of Fe atoms and S atoms is not synchronized in stronger electric field strength.Thus,the whole material system becomes chaotic and its temperature rises.The unevenly electric field force appears in the material for the nonuniform FeS distribution,so the internal stress of the composite is generated.For the internal solid lubricating phases move along the direction of the electric field to the surface of the composite,the adhesive wear and the friction coefficient reduce.The movement of the phases leaves over some voids in the composite,which induces arc wear easily.
基金the National Natural Science Foundation of China(Grant Nos.11873030 and U1938201)by the Strategic Priority Research Program of the Chinese Academy of Sciences(“multi-waveband Gravitational Wave Universe”,Grant No.XDB23040000)。
文摘Type Ia Supernovae(SNe Ia)are widely used as standard candles to probe the Universe.However,how these fierce explosions are produced itself is still a highly debated issue.There are mainly two popular models for SNe Ia:the double-degenerate scenario and the single-degenerate scenario.The doubledegenerate scenario suggests that SNe Ia are produced by the coalescence of two degenerate white dwarfs,while the single-degenerate scenario suggests that the continuous accretion of a single degenerate white dwarf from its normal stellar companion will finally lead to a disastrous explosion when it is over-massive,resulting in an SN Ia.The rapid development of the gravitational wave astronomy sheds new light on the nature of SNe Ia.In this study,we calculate the gravitational wave emissions of double white dwarf coalescences and compare them with the sensitivities of several upcoming detectors.It is found that the gravitational wave emissions from double white dwarf mergers in the local universe are strong enough to be detected by LISA.We argue that LISA-like gravitational wave detectors sensitive in the frequency range of 0.01—0.1 Hz will be a powerful tool to test the double-degenerate model of SNe Ia,and also to probe the Universe.
基金Project supported by the National Basic Research Program (973) of China(No.2007CB411600)the National Natural Science Foundation of China(No.31070205)the Key Agricultural Program of Pan’an County of Zhejiang Province,China(No.2005ZB01)
文摘Scrophularia ningpoensis has long been used in the Chinese Materia Medica for inflammation.Like other herbal medicines,S.ningpoensis collected from different localities may considerably differ in their therapeutic efficacy,and the one grown in Zhejiang Province is recognized as geo-authentic.However,it is difficult to confirm the geo-graphical authenticity by similar morphological characteristics.In the present study,inter-simple sequence repeat(ISSR) markers were conducted to detect S.ningpoensis from different origins.A 1 259-bp fragment amplified by primer UBC874 was found only in geo-authentic ones.By cloning and sequencing that specific band,sequence characterized amplified region(SCAR) markers were designed to distinguish geo-authentic S.ningpoensis from others.This is a rapid and easy method that can be used to identify the geographical authenticity of S.ningpoensis.
基金supported by the National Key Research and Development Program of China(2021YFA1300800)Strategic Priority Research Program of the Chinese Academy of Sciences(XDB0570000)+2 种基金the National Natural Science Foundation of China(32271300)the Committee of Science and Technology in Shanghai(22ZR1481300,22JC1400503)the CAS Project for Young Scientists in Basic Research(YSBR-075).
文摘Mitochondria are cellular organelles that originate from an endosymbiotic bacterial ancestor and are primarily responsible for ATP generation via oxidative phosphorylation(OXPHOS).OXPHOS is conducted by five mitochondrial respiratory complexes in the inner mitochondrial membrane.Human mitochondria possess a distinct genome,a small,circular,double-stranded DNA(mtDNA)of 16,569 base pairs.This genome encodes 37 genes.
基金This research was supported in part by the National Natural Science Foundation of China under Grant Nos.11405145,40241461,61374152,and 61876168Zhejiang Provincial Natural Science Foundation of China under Grant Nos.LY20F020024 and LY17F030016.
文摘With the increasing demand for security,building strong barrier coverage in directional sensor networks is important for effectively detecting un-authorized intrusions.In this paper,we propose an efficient scheme to form the strong barrier coverage by adding the mobile nodes one by one into the barrier.We first present the concept of target circle which determines the appropriate residence region and working direction of any candidate node to be added.Then we select the optimal relay sensor to be added into the current barrier based on its input-output ratio(barrier weight)which reflects the extension of barrier coverage.This strategy looses the demand of minimal required sensor nodes(maximal gain of each sensor)or maximal lifetime of one single barrier,leading to an augmentation of sensors to be used.Numerical simulation results show that,compared with the available schemes,the proposed method significantly reduces the minimal deploy density required to establish k-barrier,and increases the total service lifetime with a high deploy efficiency.
基金supported by the National Key Research and Development Program of China(2017YFA0504000)the National Natural Science Foundation of China(91940302,31500644,31570792,31822015,81870896,31670801)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB19010203)Shanghai Key Laboratory of Embryo Original Diseases(Shelab201904)。
文摘Aminoacyl-tRNA synthetases(aaRSs)are ubiquitously expressed,essential enzymes,synthesizing aminoacyl-tRNAs for protein synthesis.Functional defects of aaRSs frequently cause various human disorders.Human KARS encodes both cytosolic and mitochondrial lysyl-tRNA synthetases(LysRSs).Previously,two mutations(c.1129 G>A and c.517 T>C)were identified that led to hearing impairment;however,the underlying biochemical mechanism is unclear.In the present study,we found that the two mutations have no impact on the incorporation of LysRS into the multiple-synthetase complex in the cytosol,but affect the cytosolic LysRS level,its tertiary structure,and cytosolic tRNA aminoacylation in vitro.As for mitochondrial translation,the two mutations have little effect on the steady-state level,mitochondrial targeting,and tRNA binding affinity of mitochondrial LysRS.However,they exhibit striking differences in charging mitochondrial tRNALys,with the c.517T>C mutant being completely deficient in vitro and in vivo.We constructed two yeast genetic models,which are powerful tools to test the in vivo aminoacylation activity of KARS mutations at both the cytosolic and mitochondrial levels.Overall,our data provided biochemical insights into the potentially molecular pathological mechanism of KARS c.1129G>A and c.517T>C mutations and provided yeast genetic bases to investigate other KARS mutations in the future.
基金supported by the National Key Research and Development Program of China(2017YFA0504000)the Natural Science Foundation of China(91940302,31500644,31570792,31822015,81870896,31670801,31870811)+2 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB19010203)Key Laboratory of Reproductive Genetics(Zhejiang University),Ministry of Education,P.R.China(ZDFY2020-RG-0003)Shanghai Key Laboratory of Embryo Original Diseases(Shelab201904).
文摘Mutations of the genes encoding aminoacyl-tRNA synthetases are highly associated with various central nervous system disorders.Recurrent mutations,including c.5A>G,p.D2G;c.1367C>T,p.S456L;c.1535G>A,p.R512Q and c.1846_1847del,p.Y616Lfs*6 of RARS1 gene,which encodes two forms of human cytoplasmic arginyl-tRNA synthetase(hArgRS),are linked to Pelizaeus-Merzbacher-like disease(PMLD)with unclear pathogenesis.Among these mutations,c.5A>G is the most extensively reported mutation,leading to a p.D2G mutation in the N-terminal extension of the long-form hArgRS.Here,we showed the detrimental effects of R512Q substitution andΔC mutations on the structure and function of hArgRS,while the most frequent mutation c.5A>G,p.D2G acted in a different manner without impairing hArgRS activity.The nucleotide substitution c.5A>G reduced translation of hArgRS mRNA,and an upstream open reading frame contributed to the suppressed translation of the downstream main ORF.Taken together,our results elucidated distinct pathogenic mechanisms of various RARS1 mutations in PMLD.
基金supported by the Innovation Program for Quantum Science and Technology (No.2021ZD0301200)the National Natural Science Foundation of China (Nos.11804330 and 11821404)the Fundamental Research Funds for the Central Universities (WK2470000038)。
文摘The cavity quantum electrodynamics (QED) system is a promising platform for quantum optics and quantum information experiments.Its core is the strong coupling between atoms and optical cavity,which causes difficulty in the overlap between the atoms and the antinode of optical cavity mode.Here,we use a programmable movable optical dipole trap to load a cold atomic ensemble into an optical fiber microcavity and realize the strong coupling between the atoms and the optical cavity in which the coupling strength can be improved by polarization gradient cooling and adiabatic loading.By the measurement of vacuum Rabi splitting,the coupling strength can be as high as g_(N)=2π×400 MHz,which means the effective atom number is N_(eff)=16 and the collective cooperativity is C_(N)=1466.These results show that this experimental system can be used for cold atomic ensemble and cold molecule based cavity QED research.
基金supported by the National Key Research and Development Program of China(2021YFA1300800 and 2021YFC2700903)the Natural Science Foundation of China(32271300)+1 种基金the Committee of Science and Technology in Shanghai(22ZR1481300 and 22JC1400503)CAS Project for Young Scientists in Basic Research(YSBR-075).
文摘Dear Editor Coronavirus disease 2019(COVID-19),caused by severe acute respiratory syndrome coronavirus 2(SARS-CoV-2),has become a serious emergency to global public health since its outbreak in 2019.SARS-CoV-2 is an enveloped,positive-sense,single-strand RNA virus,belonging to the Betacoronavirus genus of the Coronaviridae family(Wu et al.,2020)including SARS-CoV,SARS-CoV-2,MERS-CoV,etc.
