BACKGROUND With the increasing of the global aging population,healthy aging and prevention of age-related diseases have become increasingly important.The liver,a vital organ involved in metabolism,detoxification,diges...BACKGROUND With the increasing of the global aging population,healthy aging and prevention of age-related diseases have become increasingly important.The liver,a vital organ involved in metabolism,detoxification,digestion,and immunity,holds a pivotal role in the aging process of organisms.Although extensive research on liver aging has been carried out,no bibliometric analysis has been conducted to evaluate the scientific progress in this area.AIM To analyze basic knowledge,development trends,and current research frontiers in the field via bibliometric methods.METHODS We conducted bibliometric analyses via a range of analytical tools including Python,the bibliometrix package in R,CiteSpace,and VOSviewer.We retrieved publication data on liver aging research from the Web of Science Core Collection Database.A scientific knowledge map was constructed to display the contributions from different authors,journals,countries,institutions,as well as patterns of co-occurrence keywords and co-cited references.Additionally,gene regulation pathways associated with liver aging were analyzed via the STRING database.RESULTS We identified 4288 articles on liver aging,authored by 24034 contributors from 4092 institutions across 85 countries.Notably,the years 1991 and 2020 presented significant bursts in publication output.The United States led in terms of publications(n=1008,25.1%),citations(n=55205),and international collaborations(multiple country publications=214).Keywords such as“lipid metabolism”,“fatty liver disease”,“inflammation”,“liver fibrosis”and“target”were prominent,highlighting the current research hotspots.Notably,the top 64 genes,each of which appeared in at least 8 articles,were involved in pathways essential for cell survival and aging,including the phosphatidylinositol 3-kinase/protein kinase B,Forkhead box O and p53 signaling pathways.CONCLUSION This study highlights key areas of liver aging and offers a comprehensive overview of research trends,as well as insights into potential value for collaborative pursuits and clinical implementations.展开更多
The upper reach of the Yellow River from Daliushu to Shapotou consists of five bends and has complex topography. A two-dimensional Re-Normalisation Group (RNG) k-ε model was developed to simulate the flow in the re...The upper reach of the Yellow River from Daliushu to Shapotou consists of five bends and has complex topography. A two-dimensional Re-Normalisation Group (RNG) k-ε model was developed to simulate the flow in the reach. In order to take the circulation currents in the bends into account, the momentum equations were improved by adding an additional source term. Comparison of the numerical simulation with field measurements indicates that the improved two-dimensional depth-averaged RNG k-e model can improve the accuracy of the numerical simulation. A rapid adaptive algorithm was constructed, which can automatically adjust Manning's roughness coefficient in different parts of the study river reach. As a result, not only can the trial computation time be significantly shortened, but the accuracy of the numerical simulation can also be greatly improved. Comparison of the simulated and measured water surface slopes for four typical cases shows that the longitudinal and transverse slopes of the water surface increase with the average velocity upstream. In addition, comparison was made between the positions of the talweg and the main streamline, which coincide for most of the study river reach. However, deviations between the positions of the talweg and the main streamline were found at the junction of two bends, at the position where the river width suddenly decreases or increases.展开更多
A new kind of phenyl-functionalized magnetic fibrous mesoporous silica(Fe3 O4@Si O2@KCC-1-phenyl) was prepared by copolymerization as an efficient adsorbent for the magnetic extraction of phthalate esters from environ...A new kind of phenyl-functionalized magnetic fibrous mesoporous silica(Fe3 O4@Si O2@KCC-1-phenyl) was prepared by copolymerization as an efficient adsorbent for the magnetic extraction of phthalate esters from environmental water samples. The obtained Fe3 O4@Si O2@KCC-1-phenyl showed monodisperse fibrous spherical morphology, fairly strong magnetic response(29 emu/g), and an abundant π-electron system, which allowed rapid isolation of the Fe3 O4@Si O2@KCC-1-phenyl from solutions upon applying an appropriate magnetic field. Several variables that affect the extraction efficiency of the analytes,including the type of the elution solvent, amount of adsorbent, extraction time and reusability, were investigated and optimized. Under optimum conditions, the Fe3 O4@Si O2@KCC-1-phenyl was used for the extraction of four phthalate esters from environmental water samples followed by high-performance liquid chromatographic analysis. Validation experiments indicated that the developed method presented good linearity(0.1-20 ng/m L), low limit of detection(7.5-29 μg/L, S/N =3). The proposed method was applied to the determination of phthalate esters in different real water samples, with relative recoveries of 93%-103.4%and relative standard deviation of 0.8%-8.3%.展开更多
Hybrid structures of two distinct materials provide an excellent opportunity to optimize functionalities.We report the realization of wide quantum Hall plateaus in graphene field-effect devices on the LaAlO3/SrTiO3 he...Hybrid structures of two distinct materials provide an excellent opportunity to optimize functionalities.We report the realization of wide quantum Hall plateaus in graphene field-effect devices on the LaAlO3/SrTiO3 heterostructures.Well-defined quantized Hall resistance plateaus at filling factors ν=±2 can be obtained over wide ranges of the magnetic field and gate voltage,e.g.,extending from 2 T to a maximum available magnetic field of 9 T.By using a simple band diagram model,it is revealed that these wide plateaus arise from the ultralarge capacitance of the ultra-thin LAO layer acting as the dielectric layer.This is distinctly different from the case of epitaxial graphene on Si C substrates,where the realization of giant Hall plateaus relies on the charge transfer between the graphene layer and interface states in SiC.Our results offer an alternative route towards optimizing the quantum Hall performance of graphene,which may find its applications in the further development of quantum resistance metrology.展开更多
Objective:To systematically evaluate the relationship between the miR-21 level in peripheral blood and hypertension.Methods:A systematic literature searching of CNKI,Wanfang and VIP databases,PubMed,Web of Science and...Objective:To systematically evaluate the relationship between the miR-21 level in peripheral blood and hypertension.Methods:A systematic literature searching of CNKI,Wanfang and VIP databases,PubMed,Web of Science and EMBASE by keywords was performed up to the end of November 2020.All statistical analysis was performed using the state16.0 software.Results:A total of 9 studies including 577 hypertension patients and 344 healthy controls were selected.The combined effect SMD was 1.53(95%CI:0.58-2.47,P=0.002).It is suggested that the level of miR-21 in peripheral blood of patients with hypertension is higher than that of controls.In subgroup analysis,the level of miR-21 in peripheral blood mononuclear cells(PBMC)in hypertensives was higher than that in controls(SMD=3.49,95%CI:1.24-5.74),and the difference was statistically significant(P=0.002).But the association was not found in plasma(P=0.375).No publication bias was found in our study by Begg's funnel plot and Egger's test.Conclusion:The increased level of miR-21 in peripheral blood,especially in PBMC,is a risk factor for hypertension.Limited by the number of included studies,the conclusion still needs to be verified by more high-quality studies.展开更多
The dibenzothiophene derivatives, namely 2-(dibenzothiophene-2-carbonyl)benzoic acid and 2-(diben- zothiophene-2-carbonyl)alkyl benzoate, were synthesized and characterized by nuclear magnetic resonance (1H NMR)...The dibenzothiophene derivatives, namely 2-(dibenzothiophene-2-carbonyl)benzoic acid and 2-(diben- zothiophene-2-carbonyl)alkyl benzoate, were synthesized and characterized by nuclear magnetic resonance (1H NMR), matrix-assisted laser desorption/ionization time of flight mass spectrometry, and elemental analysis. The self- association behavior of these dibenzothiophene derivatives in CH2C12 and CH3CN was investigated using UV-visible absorption spectroscopy, fourier transform infrared spec- troscopy, and atomic force microscopy. It was found that the carboxylic acid exhibited a strong self-association trend in CH2C12 solution at a concentration of about 5 × 10^-7 M. Hydrogen bonding of carboxyl in the dibenzoth- iophene derivatives was confirmed to be the main driving force for the formation of the carboxylic acid aggregates.展开更多
N-Methyl-D-aspartate receptors(NMDARs) play a central role in various physiological and pathological processes in the central nervous system.And they are commonly composed of four subunits,two GluN1 subunits and two...N-Methyl-D-aspartate receptors(NMDARs) play a central role in various physiological and pathological processes in the central nervous system.And they are commonly composed of four subunits,two GluN1 subunits and two GluN2 or GluN3 subunits.The different subunit compositions make NMDARs a heterogeneous population with distinct electrophysiological and pharmacological properties and thus with different abilities to conduct neuronal activities.The subunit composition,assembly process,and final structure of assembled NMDARs have been studied for years but no consensus has been achieved.In this study,we investigated the role of the amino terminal domain(ATD) of GluN2A in regulating NMDAR assembly.The ATD of GluN2A was first expressed in heterogeneous cells and the homodimer formation was investigated by fluorescent resonance energy transfer and non-reducing SDS- PAGE electrophoresis.Each of the three cysteine residues located in the ATD was mutated into alanine,and the homodimerization of the ATD or GluN2A,as well as the heteromeric assembly of NMDARs was assessed by non-reducing SDS- PAGE electrophoresis,co-immunoprecipitation and immunocytochemistry.We found that two cysteine residues,C87 and C320,in the ATD of the GluN2A subunit were required for the formation of disulfide bonds and GluN2A ATD homodimers.Furthermore,the disruption of GluN2A ATD domain dimerization had no influence on the assembly and surface expression of NMDARs.These results suggest that the two ATD domains of GluN2A are structurally adjacent in fully-assembled NMDARs.However,unlike GluN1,the homomerization of the ATD domain of GluN2A is not required for the assembly of NMDARs,implying that GluN2A and GluN1 play unequal roles in NMDAR assembly.展开更多
基金Supported by the National Natural Science Foundation of China,No.82271587,No.82172600,No.81972270,No.91849108,and No.82200665the National Key R&D Program of China,No.2022YFC3401601+2 种基金the Zhejiang Provincial Natural Science Foundation of China,No.LY22H030009the Zhejiang Provincial Science and Technology Program of Traditional Chinese Medicine,No.2023ZL480the Medical and Health Research Project of Zhejiang Province,No.2023RC153.
文摘BACKGROUND With the increasing of the global aging population,healthy aging and prevention of age-related diseases have become increasingly important.The liver,a vital organ involved in metabolism,detoxification,digestion,and immunity,holds a pivotal role in the aging process of organisms.Although extensive research on liver aging has been carried out,no bibliometric analysis has been conducted to evaluate the scientific progress in this area.AIM To analyze basic knowledge,development trends,and current research frontiers in the field via bibliometric methods.METHODS We conducted bibliometric analyses via a range of analytical tools including Python,the bibliometrix package in R,CiteSpace,and VOSviewer.We retrieved publication data on liver aging research from the Web of Science Core Collection Database.A scientific knowledge map was constructed to display the contributions from different authors,journals,countries,institutions,as well as patterns of co-occurrence keywords and co-cited references.Additionally,gene regulation pathways associated with liver aging were analyzed via the STRING database.RESULTS We identified 4288 articles on liver aging,authored by 24034 contributors from 4092 institutions across 85 countries.Notably,the years 1991 and 2020 presented significant bursts in publication output.The United States led in terms of publications(n=1008,25.1%),citations(n=55205),and international collaborations(multiple country publications=214).Keywords such as“lipid metabolism”,“fatty liver disease”,“inflammation”,“liver fibrosis”and“target”were prominent,highlighting the current research hotspots.Notably,the top 64 genes,each of which appeared in at least 8 articles,were involved in pathways essential for cell survival and aging,including the phosphatidylinositol 3-kinase/protein kinase B,Forkhead box O and p53 signaling pathways.CONCLUSION This study highlights key areas of liver aging and offers a comprehensive overview of research trends,as well as insights into potential value for collaborative pursuits and clinical implementations.
基金supported by the National Natural Science Foundation of China(Grants No.11361002 and 91230111)the Natural Science Foundation of Ningxia,China(Grant No.NZ13086)+1 种基金the Project of Beifang University of Nationalities,China(Grant No.2012XZK05)the Foreign Expert Project of Beifang University of Nationalities,China,and the Visiting Scholar Foundation of State Key Laboratory of Water Resources and Hydropower Engineering Science,Wuhan University,China(Grant No.2013A011)
文摘The upper reach of the Yellow River from Daliushu to Shapotou consists of five bends and has complex topography. A two-dimensional Re-Normalisation Group (RNG) k-ε model was developed to simulate the flow in the reach. In order to take the circulation currents in the bends into account, the momentum equations were improved by adding an additional source term. Comparison of the numerical simulation with field measurements indicates that the improved two-dimensional depth-averaged RNG k-e model can improve the accuracy of the numerical simulation. A rapid adaptive algorithm was constructed, which can automatically adjust Manning's roughness coefficient in different parts of the study river reach. As a result, not only can the trial computation time be significantly shortened, but the accuracy of the numerical simulation can also be greatly improved. Comparison of the simulated and measured water surface slopes for four typical cases shows that the longitudinal and transverse slopes of the water surface increase with the average velocity upstream. In addition, comparison was made between the positions of the talweg and the main streamline, which coincide for most of the study river reach. However, deviations between the positions of the talweg and the main streamline were found at the junction of two bends, at the position where the river width suddenly decreases or increases.
基金supported by the Commonwealth Scientific Foundation for Industry of Chinese Inspection and Quarantine (No.201210071) of the Ministry of National Science and Technology of ChinaChongqing Key Laboratory of Scientific Utilization of Tobacco Resources
文摘A new kind of phenyl-functionalized magnetic fibrous mesoporous silica(Fe3 O4@Si O2@KCC-1-phenyl) was prepared by copolymerization as an efficient adsorbent for the magnetic extraction of phthalate esters from environmental water samples. The obtained Fe3 O4@Si O2@KCC-1-phenyl showed monodisperse fibrous spherical morphology, fairly strong magnetic response(29 emu/g), and an abundant π-electron system, which allowed rapid isolation of the Fe3 O4@Si O2@KCC-1-phenyl from solutions upon applying an appropriate magnetic field. Several variables that affect the extraction efficiency of the analytes,including the type of the elution solvent, amount of adsorbent, extraction time and reusability, were investigated and optimized. Under optimum conditions, the Fe3 O4@Si O2@KCC-1-phenyl was used for the extraction of four phthalate esters from environmental water samples followed by high-performance liquid chromatographic analysis. Validation experiments indicated that the developed method presented good linearity(0.1-20 ng/m L), low limit of detection(7.5-29 μg/L, S/N =3). The proposed method was applied to the determination of phthalate esters in different real water samples, with relative recoveries of 93%-103.4%and relative standard deviation of 0.8%-8.3%.
基金Supported by the National Natural Science Foundation of China (Grant Nos.11974324,11804326 and U1832151)the Strategic Priority Research Program of Chinese Academy of Sciences (Grant No.XDC07010000)+2 种基金the National Key Research and Development Program of China (Grant No.2017YFA0403600)Anhui Initiative in Quantum Information Technologies (Grant No.AHY170000)Hefei Science Center CAS (Grant No.2018HSC-UE014)。
文摘Hybrid structures of two distinct materials provide an excellent opportunity to optimize functionalities.We report the realization of wide quantum Hall plateaus in graphene field-effect devices on the LaAlO3/SrTiO3 heterostructures.Well-defined quantized Hall resistance plateaus at filling factors ν=±2 can be obtained over wide ranges of the magnetic field and gate voltage,e.g.,extending from 2 T to a maximum available magnetic field of 9 T.By using a simple band diagram model,it is revealed that these wide plateaus arise from the ultralarge capacitance of the ultra-thin LAO layer acting as the dielectric layer.This is distinctly different from the case of epitaxial graphene on Si C substrates,where the realization of giant Hall plateaus relies on the charge transfer between the graphene layer and interface states in SiC.Our results offer an alternative route towards optimizing the quantum Hall performance of graphene,which may find its applications in the further development of quantum resistance metrology.
基金The fifth batch of talents selected from the"Special Support Plan"of Anhui Province(No.[2019]14)NSFC(No.81874280)+1 种基金Natural Science Foundation of Anhui Province(No.1808085QH283)Key Natural Science Research Project of Anhui Provincial Education Department(No.KJ2019A0404,KJ2019A0405)。
文摘Objective:To systematically evaluate the relationship between the miR-21 level in peripheral blood and hypertension.Methods:A systematic literature searching of CNKI,Wanfang and VIP databases,PubMed,Web of Science and EMBASE by keywords was performed up to the end of November 2020.All statistical analysis was performed using the state16.0 software.Results:A total of 9 studies including 577 hypertension patients and 344 healthy controls were selected.The combined effect SMD was 1.53(95%CI:0.58-2.47,P=0.002).It is suggested that the level of miR-21 in peripheral blood of patients with hypertension is higher than that of controls.In subgroup analysis,the level of miR-21 in peripheral blood mononuclear cells(PBMC)in hypertensives was higher than that in controls(SMD=3.49,95%CI:1.24-5.74),and the difference was statistically significant(P=0.002).But the association was not found in plasma(P=0.375).No publication bias was found in our study by Begg's funnel plot and Egger's test.Conclusion:The increased level of miR-21 in peripheral blood,especially in PBMC,is a risk factor for hypertension.Limited by the number of included studies,the conclusion still needs to be verified by more high-quality studies.
基金the National Natural Science Foundation of China (No.21376265) for financial supportthe Fundamental Research Funds for the Central Universities (No.14CX02008A)
文摘The dibenzothiophene derivatives, namely 2-(dibenzothiophene-2-carbonyl)benzoic acid and 2-(diben- zothiophene-2-carbonyl)alkyl benzoate, were synthesized and characterized by nuclear magnetic resonance (1H NMR), matrix-assisted laser desorption/ionization time of flight mass spectrometry, and elemental analysis. The self- association behavior of these dibenzothiophene derivatives in CH2C12 and CH3CN was investigated using UV-visible absorption spectroscopy, fourier transform infrared spec- troscopy, and atomic force microscopy. It was found that the carboxylic acid exhibited a strong self-association trend in CH2C12 solution at a concentration of about 5 × 10^-7 M. Hydrogen bonding of carboxyl in the dibenzoth- iophene derivatives was confirmed to be the main driving force for the formation of the carboxylic acid aggregates.
基金supported by grants from the National Basic Research Development Program of China(2010CB912002)the National Natural Science Foundation of China(30730038 and 81171164)
文摘N-Methyl-D-aspartate receptors(NMDARs) play a central role in various physiological and pathological processes in the central nervous system.And they are commonly composed of four subunits,two GluN1 subunits and two GluN2 or GluN3 subunits.The different subunit compositions make NMDARs a heterogeneous population with distinct electrophysiological and pharmacological properties and thus with different abilities to conduct neuronal activities.The subunit composition,assembly process,and final structure of assembled NMDARs have been studied for years but no consensus has been achieved.In this study,we investigated the role of the amino terminal domain(ATD) of GluN2A in regulating NMDAR assembly.The ATD of GluN2A was first expressed in heterogeneous cells and the homodimer formation was investigated by fluorescent resonance energy transfer and non-reducing SDS- PAGE electrophoresis.Each of the three cysteine residues located in the ATD was mutated into alanine,and the homodimerization of the ATD or GluN2A,as well as the heteromeric assembly of NMDARs was assessed by non-reducing SDS- PAGE electrophoresis,co-immunoprecipitation and immunocytochemistry.We found that two cysteine residues,C87 and C320,in the ATD of the GluN2A subunit were required for the formation of disulfide bonds and GluN2A ATD homodimers.Furthermore,the disruption of GluN2A ATD domain dimerization had no influence on the assembly and surface expression of NMDARs.These results suggest that the two ATD domains of GluN2A are structurally adjacent in fully-assembled NMDARs.However,unlike GluN1,the homomerization of the ATD domain of GluN2A is not required for the assembly of NMDARs,implying that GluN2A and GluN1 play unequal roles in NMDAR assembly.