维护金融市场稳定、防控金融风险是我国经济建设的重要内容。基于Gelfand et al.(2006)提出的文化遵从度理论框架,本文以2008—2019年中国A股上市公司为样本,从股价崩盘风险的视角,探究了非正式制度对金融市场稳定的影响。研究发现:公...维护金融市场稳定、防控金融风险是我国经济建设的重要内容。基于Gelfand et al.(2006)提出的文化遵从度理论框架,本文以2008—2019年中国A股上市公司为样本,从股价崩盘风险的视角,探究了非正式制度对金融市场稳定的影响。研究发现:公司所在地的文化遵从度对公司未来股价崩盘风险存在显著影响,当地文化遵从度越高,公司的股价崩盘风险越低。进一步发现:(1)提高信息质量和选择四大审计,是文化遵从度影响公司股价崩盘风险的主要机制;(2)区分文化遵从度的作用强度后,文化遵从度对股价崩盘风险的影响在成立年限长、高管不具有海外经历的公司表现得更强烈;(3)结合公司治理的其他机制,在公司内外部治理机制较弱时,文化遵从度发挥了较强的治理作用;(4)比较公司所在地的文化遵从度与高管籍贯所在地,公司所在地的文化遵从度具有更强的影响作用,表明文化遵从度能够对个体产生“同化”影响。本文的研究揭示了非正式制度对公司股价崩盘风险的重要影响,对于维护金融市场的稳定、防范金融风险,具有一定的理论和现实启发。展开更多
Uniaxial strain is a powerful tuning parameter that can control symmetry and anisotropic electronic properties in iron-based superconductors.However,accurately characterizing anisotropic strain can be challenging and ...Uniaxial strain is a powerful tuning parameter that can control symmetry and anisotropic electronic properties in iron-based superconductors.However,accurately characterizing anisotropic strain can be challenging and complex.Here,we utilize a cryogenic optical system equipped with a high-spatial-resolution microscope to characterize surface strains in iron-based superconductors using the digital image correlation method.Compared with other methods such as high-resolution x-ray diffraction,strain gauge,and capacitive sensor,digital image correlation offers a non-contact full-field measurement approach,acting as an optical virtual strain gauge that provides high spatial resolution.The results measured on detwinned BaFe_(2)As_(2)are quantitatively consistent with the distortion measured by x-ray diffraction and neutron Larmor diffraction.These findings highlight the potential of cryogenic digital image correlation as an effective and accessible tool for probing the isotropic and anisotropic strains,facilitating applications of uniaxial strain tuning in research of quantum materials.展开更多
SBA-15 with varied pore size from 4 to 8 nm were synthesized by tuning the temperature of hydrothermal treatment,the supports were then used to load the active phase Cr Oxthrough a conventional impregnation method.The...SBA-15 with varied pore size from 4 to 8 nm were synthesized by tuning the temperature of hydrothermal treatment,the supports were then used to load the active phase Cr Oxthrough a conventional impregnation method.The resulting catalysts were characterized by small/wide angle XRD,N_(2) adsorption/desorption,FT-IR,TEM-EDX,XPS,TPR and CO_(2)-TPD to study the feature of structure,surface chemical state,redox and basicity.It was found from these results that the metal species could be well dispersed on catalysts with larger pore size.Cr^(6+)species could enter into the framework by substituting the Si atoms of SBA-15,and Cr^(3+)mainly exist on extra framework.Pore size had profound effects on reducibility,surface composition and basicity.Cr^(6+)species were necessary to activate the C-H bonds of alkanes,while the basicity played an important role in activating C-O bonds of CO_(2).The best performances were achieved over the sample Cr supported on SBA-15 with a pore diameter of 7 nm in oxidative dehydrogenation of ethane in the presence of CO_(2).展开更多
Osteocytes reside as three-dimensionally（3D） networked cells in the lacunocanalicular structure of bones and regulate bone and mineral homeostasis. Despite of their important regulatory roles, in vitro studies of os...Osteocytes reside as three-dimensionally（3D） networked cells in the lacunocanalicular structure of bones and regulate bone and mineral homeostasis. Despite of their important regulatory roles, in vitro studies of osteocytes have been challenging because：（1） current cell lines do not sufficiently represent the phenotypic features of mature osteocytes and（2） primary cells rapidly differentiate to osteoblasts upon isolation. In this study, we used a 3D perfusion culture approach to：（1） construct the 3D cellular network of primary murine osteocytes by biomimetic assembly with microbeads and（2） reproduce ex vivo the phenotype of primary murine osteocytes, for the first time to our best knowledge. In order to enable 3D construction with a sufficient number of viable cells, we used a proliferated osteoblastic population of healthy cells outgrown from digested bone chips. The diameter of microbeads was controlled to：（1） distribute and entrap cells within the interstitial spaces between the microbeads and（2） maintain average cell-to-cell distance to be about 19 mm. The entrapped cells formed a 3D cellular network by extending and connecting their processes through openings between the microbeads. Also, with increasing culture time, the entrapped cells exhibited the characteristic gene expressions（SOST and FGF23） and nonproliferative behavior of mature osteocytes. In contrast, 2D-cultured cells continued their osteoblastic differentiation and proliferation. This 3D biomimetic approach is expected to provide a new means of：（1） studying flow-induced shear stress on the mechanotransduction function of primary osteocytes,（2） studying physiological functions of 3D-networked osteocytes with in vitro convenience,and（3） developing clinically relevant human bone disease models.展开更多
Silicon carbide(SiC)material features a wide bandgap and high critical breakdown field intensity.It also plays an important role in the high efficiency and miniaturization of power electronic equipment.It is an ideal ...Silicon carbide(SiC)material features a wide bandgap and high critical breakdown field intensity.It also plays an important role in the high efficiency and miniaturization of power electronic equipment.It is an ideal choice for new power electronic devices,especially in smart grids and high-speed trains.In the medium and high voltage fields,SiC devices with a blocking voltage of more than 6.5 kV will have a wide range of applications.In this paper,we study the influence of epitaxial material properties on the static characteristics of 6.5 kV SiC MOSFET.6.5 kV SiC MOSFETs with different channel lengths and JFET region widths are manufactured on three wafers and analyzed.The FN tunneling of gate oxide,HTGB and HTRB tests are performed and provide data support for the industrialization process for medium/high voltage SiC MOSFETs.展开更多
Objective:To find the target genes in combination of astragalus root(Astragalus membranaceus)and spindle tree wings(Euonymus alatus(THUNB.)SIEB.)(Qijian Heji)with the function of regulating blood glucose levels in kk ...Objective:To find the target genes in combination of astragalus root(Astragalus membranaceus)and spindle tree wings(Euonymus alatus(THUNB.)SIEB.)(Qijian Heji)with the function of regulating blood glucose levels in kk mice by real-time fluorescence quantitative PCR(RT-PCR).To achieve the primary exploration on the material basis for Qijian Heji to improve the blood glucose levels of type 2 diabetic kk mice.Methods:We applied RT-PCR to detecting the expression of gene targets in kidney tissues of type 2 diabetes model kk mice.The detected gene targets were predicted by the network pharmacology method in the early stage of the project.Through the observation of the hypoglycemic effect of different ratios of Qijian Heji,the optimal proportion was determined and then used to conduct research of material basis.Results:Continuous administration of Qijian Heji(astragalus root:spindle tree wings Z 3:1)for six weeks resulted in significantly lowering blood glucose levels in mice in the fourth week,dropping from 33.3 to 21.9 mmol/L;this lower level was maintained in the fifth to sixth weeks.Blood glucose values in the positive drug group decreased from 33.3 to 21.85 mmol/L in the fourth week and maintained steady decreasing in the fifth and sixth weeks.Conclusion:Qijian Heji,with proportion of 3:1,could significantly reduce the blood glucose values in kk mice,animal experiment results verified the accurate prediction of network pharmacology,and at the same time,it is verified there was a certain therapeutic effect about the combination of the two herbs on reducing the glucose value.Animal experiments and RT-PCR results showed that Qijian Heji conducted a hypoglycemic effect by modulating estrogen receptor(ESR1)and renin(REN)expression.展开更多
Multiple phase transitions are detected in sodium amide(NaNH2), an important hydrogen storage material, upon compression in diamond anvil cells(DAC) by using Raman spectroscopy and x-ray diffraction(XRD) measurements....Multiple phase transitions are detected in sodium amide(NaNH2), an important hydrogen storage material, upon compression in diamond anvil cells(DAC) by using Raman spectroscopy and x-ray diffraction(XRD) measurements.Additional Bragg reflections appear on lower and higher angle sides of the original ones at ~1.07 GPa and 1.84 GPa,accompanied by obvious changes in Raman spectroscopy, respectively.It reveals that NaNH2 undergoes the high-pressure phase sequence(α-β-γ) up to 20 GPa at room temperature.Spectral analysis indicates an orthorhombic structure with PBAN space group for the γ phase.We also experimentally observe high pressure induced recrystallization in alkaline amide compounds for the first time.展开更多
The genus Lissothrips Hood, 1908 is reported for the first time in China. The newly recorded species Lissothrips okajimai Mound, 1989 is illustrated and redescribed. A checklist of the genus Lissothrips worldwide is p...The genus Lissothrips Hood, 1908 is reported for the first time in China. The newly recorded species Lissothrips okajimai Mound, 1989 is illustrated and redescribed. A checklist of the genus Lissothrips worldwide is presented.展开更多
Most of the existing machine learning studies in logs interpretation do not consider the data distribution discrepancy issue,so the trained model cannot well generalize to the unseen data without calibrating the logs....Most of the existing machine learning studies in logs interpretation do not consider the data distribution discrepancy issue,so the trained model cannot well generalize to the unseen data without calibrating the logs.In this paper,we formulated the geophysical logs calibration problem and give its statistical explanation,and then exhibited an interpretable machine learning method,i.e.,Unilateral Alignment,which could align the logs from one well to another without losing the physical meanings.The involved UA method is an unsupervised feature domain adaptation method,so it does not rely on any labels from cores.The experiments in 3 wells and 6 tasks showed the effectiveness and interpretability from multiple views.展开更多
The intelligent textile sensors based on fiber(1D)and fabric(2D)are the ideal candidates for wearable devices.Their flexible weaving and unique structure endow them with flexibility,lightweight,good air permeability,a...The intelligent textile sensors based on fiber(1D)and fabric(2D)are the ideal candidates for wearable devices.Their flexible weaving and unique structure endow them with flexibility,lightweight,good air permeability,and feasible integration with garments.In view of the spring-up of novel textile-based strain sensors,the novel materials and fabrication approaches were elaborated from spatial perspectives,i.e.,1D fibers/yarn and 2D fabric.The intrinsic sensing mechanism is the primary fac-tor affecting sensor sensitivity,and the variation trend of the sensing signal is closely related to it.Although existing studies have involved various sensing mechanisms,there is still lacking systematic classification and discussion.Hence,the sensing mechanisms of textile-based sensors were elaborated from spatial perspectives.Considering that strain sensors were mostly based on resistance variation,the sensing mechanisms of resistive textile-based strain sensors were mainly focused,mainly including fiber deformation,tunneling effect,crack propagation,fabric deformation,electrical contact and bridge connec-tion.Meanwhile,the corresponding resistance prediction models,usually used as important data fitting methodology,were also comprehensively discussed,which can reproduce the resistance trend and provide guidance for the sensor performance.Finally,the multifunctionality of textile-based strain sensors was summarized,namely multi-mode signal detection,visual interaction,energy collection,thermal management and medical treatment were discussed.It was expected to provide research insights into the multifunctional integration of textile sensors.展开更多
More than 80%of plants form mutualistic symbiotic relationships with arbuscular mycorrhizal fungi(AMF),and the application of fertilizers,such as nitrogen(N)and phosphorus(P)fertilizers,is a common agricultural manage...More than 80%of plants form mutualistic symbiotic relationships with arbuscular mycorrhizal fungi(AMF),and the application of fertilizers,such as nitrogen(N)and phosphorus(P)fertilizers,is a common agricultural management practice to improve crop yield and quality.However,the potential effects of long-term N and P fertilization on the AMF community in the rainfed agricultural system of the Loess Plateau of China are still not well understood.In this study,a long-term field experiment was conducted based on orthogonal design,with three N levels(0,90,and 180 kg ha^(-1)year^(-1))and three P levels(0,90,and 180 kg ha^(-1)year^(-1))for wheat fertilization.Changes in AMF community and correlations between AMF community composition,soil environmental factors,and wheat yield component traits were analyzed using traditional biochemical methods and high-throughput sequencing technology.The results showed that long-term N and P addition had a significant effect on the AMF community structure and composition.Nitrogen application alone significantly reduced the richness and diversity of AMF community,whereas the combined application of N and P significantly increased the richness and diversity of AMF community.The AMF community was driven mainly by soil available P,total P,and pH.There was a significant positive correlation between Glomus abundance and wheat yield and a significant negative correlation between Paraglomus abundance and wheat yield.Long-term N and P addition directly increased crop yield and affected yield indirectly by influencing soil chemical properties and the AMF community.Combined application of N and P both at90 kg ha^(-1)year^(-1)could improve the ecological and physiological functions of the AMF community and benefit the sustainable development of rainfed agriculture.展开更多
In this paper,we give a suficient condition under which an involution monoid generates a variety with continuum many subvarieties.According to this result,several involution J-trivial monoids are shown to generate var...In this paper,we give a suficient condition under which an involution monoid generates a variety with continuum many subvarieties.According to this result,several involution J-trivial monoids are shown to generate varieties with continuum many subvarieties.These examples include Rees quotients of free involution monoids,Lee monoids with involution,and Straubing monoids with involution.展开更多
Using rumor verification data from investor interactive platforms,we investigate the effect of stock market rumors on price efficiency.We find favorable rumors are positively correlated with stock price synchronicity,...Using rumor verification data from investor interactive platforms,we investigate the effect of stock market rumors on price efficiency.We find favorable rumors are positively correlated with stock price synchronicity,while unfavorable rumors are negatively correlated with stock price synchronicity.Both favorable and unfavorable rumors are positively correlated with stock mispricing levels,and stock price crash risk.Mechanism tests reveal that favorable rumors about industry leaders have industry spillover effects.The effect of rumors on mispricing levels and stock price crash risk are more pronounced when there are more retail investors.Further analysis shows stronger detrimental impacts of rumors on price efficiency for small-cap companies,companies with low information transparency and companies with low institutional ownership.展开更多
Alkaligrass(Puccinellia tenuiflora) is a monocotyledonous halophytic forage grass widely distributed in Northern China. It belongs to the Gramineae family and shares a close phylogenetic relationship with the cereal c...Alkaligrass(Puccinellia tenuiflora) is a monocotyledonous halophytic forage grass widely distributed in Northern China. It belongs to the Gramineae family and shares a close phylogenetic relationship with the cereal crops, wheat and barley. Here, we present a high-quality chromosome-level genome sequence of alkaligrass assembled from Illumina, Pac Bio and 10× Genomics reads combined with genome-wide chromosome conformation capture(Hi-C) data. The ~1.50 Gb assembled alkaligrass genome encodes 38,387 protein-coding genes, and 54.9% of the assembly are transposable elements, with long terminal repeats being the most abundant. Comparative genomic analysis coupled with stress-treated transcriptome profiling uncovers a set of unique saline-and alkaline-responsive genes in alkaligrass. The high-quality genome assembly and the identified stress related genes in alkaligrass provide an important resource for evolutionary genomic studies in Gramineae and facilitate further understanding of molecular mechanisms underlying stress tolerance in monocotyledonous halophytes. The alkaligrass genome data is freely available at http://xhhuanglab.cn/data/alkaligrass.html.展开更多
In-plane symmetry is an important contributor to the physical properties of two-dimensional layered materials, as well as atomically thin heterojunctions. Here, we demonstrate anisotropic/isotropic van der Waals （vdW...In-plane symmetry is an important contributor to the physical properties of two-dimensional layered materials, as well as atomically thin heterojunctions. Here, we demonstrate anisotropic/isotropic van der Waals （vdW） heterostructures of ReS2 and MoS2 monolayers, where interlayer coupling interactions and charge separation were observed by in situ Raman-photoluminescence spectroscopy, electrical, and photoelectrical measurements. We believe that these results could be helpful for understanding the fundamental physics of atomically thin vdW heterostructures and creating novel electronic and optoelectronic devices.展开更多
Numerous commercial organic fluorophores with excellent optical properties are precluded from live-cell superresolution imaging due to poor cell permeability.Here,we develop a simple but effective strategy that render...Numerous commercial organic fluorophores with excellent optical properties are precluded from live-cell superresolution imaging due to poor cell permeability.Here,we develop a simple but effective strategy that renders cells permeable to cell-impermeable,organic fluorescent probes by using a novel peptide vehicle,PV-1.By simple coincubation with PV-1,22 different cell-impermeable,organic fluorescent probes were efficiently delivered into live cells and specifically labeled a variety of organelles.Moreover,PV-1 can simultaneously transfer up to three different probes into live cells.By using PV-1 and these cell-impermeable fluorescent probes,we obtained multicolor,longterm,live-cell superresolution images of various organelles,which allowed us to study the dynamic interactions between them.PV-1,together with these organic fluorescent probes,will greatly broaden the applications of superresolution imaging technology in diverse live-cell studies and opens up a new avenue in the design and application of peptide vehicles.展开更多
OBJECTIVE: To investigate the effects of Sini San and fluoxetine on the levels of central and peripheral 5-HT in a rat model of depression, and provide new insight into the treatment of depression with integrated Chin...OBJECTIVE: To investigate the effects of Sini San and fluoxetine on the levels of central and peripheral 5-HT in a rat model of depression, and provide new insight into the treatment of depression with integrated Chinese-Western Medicine.METHODS: A rat model of depression was established by chronic mild stress(CMS). Model rats received either Sini San, fluoxetine, a combination of the two drugs, or no drug treatment. Healthy naive rats were used as controls. Open field and sucrose preference tests were used to assess depression-like behavior. ELISA and immunohistochemistry were used to determine central and peripheral levels of 5-HT.RESULTS: In the group with no drug treatment,central 5-HT expression decreased while peripheral5-HT concentrations increased as CMS continued.Four weeks after CMS, Sini San alone was less effective in reducing depression-like behavior than fluoxetine alone or in combination with Sini San,but combined use was more effective than fluoxetine alone. Eight weeks after CMS, Sini San alone or in combination with fluoxetine was more effective in reducing depression-like behavior than fluoxetine alone. Furthermore Sini San and fluoxetine used alone or in combination notably increased central 5-HT expression and decreased peripheral 5-HT levels in the rat model.CONCLUSION:The results of the present study indicate that there is a synergistic action between the two medicines in the treatment of depression. Sini San exhibited a relatively long lag before its effects were observed; however, by eight weeks the Traditional Chinese Medicine appeared at least as effective as fluoxetine. We suggest that Sini San can replace fluoxetine in the later stages of depression treatment to minimize side effects observed with long-term fluoxetine administration.展开更多
The scope and variety of the metabolic intermediates from the mitochondrial tricarboxylic acid(TCA)cycle that are engaged in epigenetic regulation of the chromatin function in the nucleus raise an outstanding question...The scope and variety of the metabolic intermediates from the mitochondrial tricarboxylic acid(TCA)cycle that are engaged in epigenetic regulation of the chromatin function in the nucleus raise an outstanding question about how timely and precise supply/consumption of these metabolites is achieved in the nucleus.We report here the identification of a nonclassical TCA cycle in the nucleus(nTCA cycle).We found that all the TCA cycle-associated enzymes including citrate synthase(CS),aconitase 2(ACO2),isocitrate dehydrogenase 3(IDH3),oxoglutarate dehydrogenase(OGDH),succinyl-CoA synthetase(SCS),fumarate hydratase(FH),and malate dehydrogenase 2(MDH2),except for succinate dehydrogenase(SDH),a component of electron transport chain for generating ATP,exist in the nucleus.We showed that these nuclear enzymes catalyze an incomplete TCA cycle similar to that found in cyanobacteria.We propose that the nTCA cycle is implemented mainly to generate/consume metabolic intermediates,not for energy production.We demonstrated that the nTCA cycle is intrinsically linked to chromatin dynamics and transcription regulation.Together,our study uncovers the existence of a nonclassical TCA cycle in the nucleus that links the metabolic pathway to epigenetic regulation.展开更多
文摘维护金融市场稳定、防控金融风险是我国经济建设的重要内容。基于Gelfand et al.(2006)提出的文化遵从度理论框架,本文以2008—2019年中国A股上市公司为样本,从股价崩盘风险的视角,探究了非正式制度对金融市场稳定的影响。研究发现:公司所在地的文化遵从度对公司未来股价崩盘风险存在显著影响,当地文化遵从度越高,公司的股价崩盘风险越低。进一步发现:(1)提高信息质量和选择四大审计,是文化遵从度影响公司股价崩盘风险的主要机制;(2)区分文化遵从度的作用强度后,文化遵从度对股价崩盘风险的影响在成立年限长、高管不具有海外经历的公司表现得更强烈;(3)结合公司治理的其他机制,在公司内外部治理机制较弱时,文化遵从度发挥了较强的治理作用;(4)比较公司所在地的文化遵从度与高管籍贯所在地,公司所在地的文化遵从度具有更强的影响作用,表明文化遵从度能够对个体产生“同化”影响。本文的研究揭示了非正式制度对公司股价崩盘风险的重要影响,对于维护金融市场的稳定、防范金融风险,具有一定的理论和现实启发。
基金supported by the National Key Research and Development Program of China(Grant No.2021YFA1400400)the Fundamental Research Funds for the Central Universities,and the National Natural Science Foundation of China(Grant Nos.12174029 and 11922402).
文摘Uniaxial strain is a powerful tuning parameter that can control symmetry and anisotropic electronic properties in iron-based superconductors.However,accurately characterizing anisotropic strain can be challenging and complex.Here,we utilize a cryogenic optical system equipped with a high-spatial-resolution microscope to characterize surface strains in iron-based superconductors using the digital image correlation method.Compared with other methods such as high-resolution x-ray diffraction,strain gauge,and capacitive sensor,digital image correlation offers a non-contact full-field measurement approach,acting as an optical virtual strain gauge that provides high spatial resolution.The results measured on detwinned BaFe_(2)As_(2)are quantitatively consistent with the distortion measured by x-ray diffraction and neutron Larmor diffraction.These findings highlight the potential of cryogenic digital image correlation as an effective and accessible tool for probing the isotropic and anisotropic strains,facilitating applications of uniaxial strain tuning in research of quantum materials.
基金financial supports from National Natural Science Foundation of China(No.21603153)Science and Technology Department of Sichuan Province(No.2016HH0026)the Fundamental Research Funds for the Central Universities(No.YJ201544)。
文摘SBA-15 with varied pore size from 4 to 8 nm were synthesized by tuning the temperature of hydrothermal treatment,the supports were then used to load the active phase Cr Oxthrough a conventional impregnation method.The resulting catalysts were characterized by small/wide angle XRD,N_(2) adsorption/desorption,FT-IR,TEM-EDX,XPS,TPR and CO_(2)-TPD to study the feature of structure,surface chemical state,redox and basicity.It was found from these results that the metal species could be well dispersed on catalysts with larger pore size.Cr^(6+)species could enter into the framework by substituting the Si atoms of SBA-15,and Cr^(3+)mainly exist on extra framework.Pore size had profound effects on reducibility,surface composition and basicity.Cr^(6+)species were necessary to activate the C-H bonds of alkanes,while the basicity played an important role in activating C-O bonds of CO_(2).The best performances were achieved over the sample Cr supported on SBA-15 with a pore diameter of 7 nm in oxidative dehydrogenation of ethane in the presence of CO_(2).
基金the National Institute of Arthritis and Musculoskeletal and Skin Diseases of the National Institutes of Health (1R21AR065032 to W.Y.L and J.Z.)the National Science Foundation (DMR 1409779 to W.Y.L and J.Z.)
文摘Osteocytes reside as three-dimensionally（3D） networked cells in the lacunocanalicular structure of bones and regulate bone and mineral homeostasis. Despite of their important regulatory roles, in vitro studies of osteocytes have been challenging because：（1） current cell lines do not sufficiently represent the phenotypic features of mature osteocytes and（2） primary cells rapidly differentiate to osteoblasts upon isolation. In this study, we used a 3D perfusion culture approach to：（1） construct the 3D cellular network of primary murine osteocytes by biomimetic assembly with microbeads and（2） reproduce ex vivo the phenotype of primary murine osteocytes, for the first time to our best knowledge. In order to enable 3D construction with a sufficient number of viable cells, we used a proliferated osteoblastic population of healthy cells outgrown from digested bone chips. The diameter of microbeads was controlled to：（1） distribute and entrap cells within the interstitial spaces between the microbeads and（2） maintain average cell-to-cell distance to be about 19 mm. The entrapped cells formed a 3D cellular network by extending and connecting their processes through openings between the microbeads. Also, with increasing culture time, the entrapped cells exhibited the characteristic gene expressions（SOST and FGF23） and nonproliferative behavior of mature osteocytes. In contrast, 2D-cultured cells continued their osteoblastic differentiation and proliferation. This 3D biomimetic approach is expected to provide a new means of：（1） studying flow-induced shear stress on the mechanotransduction function of primary osteocytes,（2） studying physiological functions of 3D-networked osteocytes with in vitro convenience,and（3） developing clinically relevant human bone disease models.
基金the support of the National Key Research and Development Program(Grant No.2016YFB0400500)the Science&Technology Program of the State Grid Corporation of China Co.,Ltd.“High voltage and high power SiC materials,devices and the application demonstration in power electronic transformers”.
文摘Silicon carbide(SiC)material features a wide bandgap and high critical breakdown field intensity.It also plays an important role in the high efficiency and miniaturization of power electronic equipment.It is an ideal choice for new power electronic devices,especially in smart grids and high-speed trains.In the medium and high voltage fields,SiC devices with a blocking voltage of more than 6.5 kV will have a wide range of applications.In this paper,we study the influence of epitaxial material properties on the static characteristics of 6.5 kV SiC MOSFET.6.5 kV SiC MOSFETs with different channel lengths and JFET region widths are manufactured on three wafers and analyzed.The FN tunneling of gate oxide,HTGB and HTRB tests are performed and provide data support for the industrialization process for medium/high voltage SiC MOSFETs.
基金the National Natural Science Foundation of China.(No.81102730 and No.81302914)Postgraduate Project of Beijing University of Chinese Medicine(No.2015-JYB-XS044).
文摘Objective:To find the target genes in combination of astragalus root(Astragalus membranaceus)and spindle tree wings(Euonymus alatus(THUNB.)SIEB.)(Qijian Heji)with the function of regulating blood glucose levels in kk mice by real-time fluorescence quantitative PCR(RT-PCR).To achieve the primary exploration on the material basis for Qijian Heji to improve the blood glucose levels of type 2 diabetic kk mice.Methods:We applied RT-PCR to detecting the expression of gene targets in kidney tissues of type 2 diabetes model kk mice.The detected gene targets were predicted by the network pharmacology method in the early stage of the project.Through the observation of the hypoglycemic effect of different ratios of Qijian Heji,the optimal proportion was determined and then used to conduct research of material basis.Results:Continuous administration of Qijian Heji(astragalus root:spindle tree wings Z 3:1)for six weeks resulted in significantly lowering blood glucose levels in mice in the fourth week,dropping from 33.3 to 21.9 mmol/L;this lower level was maintained in the fifth to sixth weeks.Blood glucose values in the positive drug group decreased from 33.3 to 21.85 mmol/L in the fourth week and maintained steady decreasing in the fifth and sixth weeks.Conclusion:Qijian Heji,with proportion of 3:1,could significantly reduce the blood glucose values in kk mice,animal experiment results verified the accurate prediction of network pharmacology,and at the same time,it is verified there was a certain therapeutic effect about the combination of the two herbs on reducing the glucose value.Animal experiments and RT-PCR results showed that Qijian Heji conducted a hypoglycemic effect by modulating estrogen receptor(ESR1)and renin(REN)expression.
基金Project supported by the National Key R&D Program of China(Grant Nos.2018YFA0305900 and 2016YFB0201204)the National Natural Science Foundation of China(Grant Nos.51632002,51572108,11504127,91745203,and 11634004)+1 种基金Program for Changjiang Scholars and Innovative Research Team in University,China(Grant No.IRT 15R23)National Fund for Fostering Talents of Basic Science,China(Grant No.J1103202)
文摘Multiple phase transitions are detected in sodium amide(NaNH2), an important hydrogen storage material, upon compression in diamond anvil cells(DAC) by using Raman spectroscopy and x-ray diffraction(XRD) measurements.Additional Bragg reflections appear on lower and higher angle sides of the original ones at ~1.07 GPa and 1.84 GPa,accompanied by obvious changes in Raman spectroscopy, respectively.It reveals that NaNH2 undergoes the high-pressure phase sequence(α-β-γ) up to 20 GPa at room temperature.Spectral analysis indicates an orthorhombic structure with PBAN space group for the γ phase.We also experimentally observe high pressure induced recrystallization in alkaline amide compounds for the first time.
基金supported by the National Science Foundation of China (31272344)the College Research Project of Weinan Vocational and Technical College of 2013 (WZYZ201307)the science and technology projects in Weinan (2016KYJ-4-4)
文摘The genus Lissothrips Hood, 1908 is reported for the first time in China. The newly recorded species Lissothrips okajimai Mound, 1989 is illustrated and redescribed. A checklist of the genus Lissothrips worldwide is presented.
基金Supported in part by the National Natural Science Foundation of China under Grant 61903353in part by the SINOPEC Programmes for Science and Technology Development under Grant PE19008-8.
文摘Most of the existing machine learning studies in logs interpretation do not consider the data distribution discrepancy issue,so the trained model cannot well generalize to the unseen data without calibrating the logs.In this paper,we formulated the geophysical logs calibration problem and give its statistical explanation,and then exhibited an interpretable machine learning method,i.e.,Unilateral Alignment,which could align the logs from one well to another without losing the physical meanings.The involved UA method is an unsupervised feature domain adaptation method,so it does not rely on any labels from cores.The experiments in 3 wells and 6 tasks showed the effectiveness and interpretability from multiple views.
基金supported by the major project of the National Natural Science Foundation of China(52090033/52090030).
文摘The intelligent textile sensors based on fiber(1D)and fabric(2D)are the ideal candidates for wearable devices.Their flexible weaving and unique structure endow them with flexibility,lightweight,good air permeability,and feasible integration with garments.In view of the spring-up of novel textile-based strain sensors,the novel materials and fabrication approaches were elaborated from spatial perspectives,i.e.,1D fibers/yarn and 2D fabric.The intrinsic sensing mechanism is the primary fac-tor affecting sensor sensitivity,and the variation trend of the sensing signal is closely related to it.Although existing studies have involved various sensing mechanisms,there is still lacking systematic classification and discussion.Hence,the sensing mechanisms of textile-based sensors were elaborated from spatial perspectives.Considering that strain sensors were mostly based on resistance variation,the sensing mechanisms of resistive textile-based strain sensors were mainly focused,mainly including fiber deformation,tunneling effect,crack propagation,fabric deformation,electrical contact and bridge connec-tion.Meanwhile,the corresponding resistance prediction models,usually used as important data fitting methodology,were also comprehensively discussed,which can reproduce the resistance trend and provide guidance for the sensor performance.Finally,the multifunctionality of textile-based strain sensors was summarized,namely multi-mode signal detection,visual interaction,energy collection,thermal management and medical treatment were discussed.It was expected to provide research insights into the multifunctional integration of textile sensors.
基金jointly funded by a project of the Science and Technology Department of Shaanxi Province,China(No.2022NY-074)the National Natural Science Foundation of China(Nos.41501255 and 41671269)+1 种基金Xi’an Science and Technology Project,China(No.21NYYF0033)the Fundamental Research Funds for the Central Universities,China(No.SYJS202224)。
文摘More than 80%of plants form mutualistic symbiotic relationships with arbuscular mycorrhizal fungi(AMF),and the application of fertilizers,such as nitrogen(N)and phosphorus(P)fertilizers,is a common agricultural management practice to improve crop yield and quality.However,the potential effects of long-term N and P fertilization on the AMF community in the rainfed agricultural system of the Loess Plateau of China are still not well understood.In this study,a long-term field experiment was conducted based on orthogonal design,with three N levels(0,90,and 180 kg ha^(-1)year^(-1))and three P levels(0,90,and 180 kg ha^(-1)year^(-1))for wheat fertilization.Changes in AMF community and correlations between AMF community composition,soil environmental factors,and wheat yield component traits were analyzed using traditional biochemical methods and high-throughput sequencing technology.The results showed that long-term N and P addition had a significant effect on the AMF community structure and composition.Nitrogen application alone significantly reduced the richness and diversity of AMF community,whereas the combined application of N and P significantly increased the richness and diversity of AMF community.The AMF community was driven mainly by soil available P,total P,and pH.There was a significant positive correlation between Glomus abundance and wheat yield and a significant negative correlation between Paraglomus abundance and wheat yield.Long-term N and P addition directly increased crop yield and affected yield indirectly by influencing soil chemical properties and the AMF community.Combined application of N and P both at90 kg ha^(-1)year^(-1)could improve the ecological and physiological functions of the AMF community and benefit the sustainable development of rainfed agriculture.
基金supported by the National Natural Science Foundation of China(Nos.12271224,12171213,11771191)the Fundamental Research Funds for the Central Universities(No.lzujbky-2023-ey06)the Natural Science Foundation of Gansu Province(No.20JR5RA275).
文摘In this paper,we give a suficient condition under which an involution monoid generates a variety with continuum many subvarieties.According to this result,several involution J-trivial monoids are shown to generate varieties with continuum many subvarieties.These examples include Rees quotients of free involution monoids,Lee monoids with involution,and Straubing monoids with involution.
基金supported by the National Natural Science Foundation of China(Project Nos.71902201 and 71972189).
文摘Using rumor verification data from investor interactive platforms,we investigate the effect of stock market rumors on price efficiency.We find favorable rumors are positively correlated with stock price synchronicity,while unfavorable rumors are negatively correlated with stock price synchronicity.Both favorable and unfavorable rumors are positively correlated with stock mispricing levels,and stock price crash risk.Mechanism tests reveal that favorable rumors about industry leaders have industry spillover effects.The effect of rumors on mispricing levels and stock price crash risk are more pronounced when there are more retail investors.Further analysis shows stronger detrimental impacts of rumors on price efficiency for small-cap companies,companies with low information transparency and companies with low institutional ownership.
基金supported by grants from the National Key Research and Development Program of China(2018YFA090060)the Foundation of Shanghai Science and Technology Committee(17391900600)+1 种基金the Fund of Shanghai Engineering Research Center of Plant Germplasm Resources(17DZ2252700)the Natural Science Foundation of Heilongjiang Province(ZD2019C003)。
文摘Alkaligrass(Puccinellia tenuiflora) is a monocotyledonous halophytic forage grass widely distributed in Northern China. It belongs to the Gramineae family and shares a close phylogenetic relationship with the cereal crops, wheat and barley. Here, we present a high-quality chromosome-level genome sequence of alkaligrass assembled from Illumina, Pac Bio and 10× Genomics reads combined with genome-wide chromosome conformation capture(Hi-C) data. The ~1.50 Gb assembled alkaligrass genome encodes 38,387 protein-coding genes, and 54.9% of the assembly are transposable elements, with long terminal repeats being the most abundant. Comparative genomic analysis coupled with stress-treated transcriptome profiling uncovers a set of unique saline-and alkaline-responsive genes in alkaligrass. The high-quality genome assembly and the identified stress related genes in alkaligrass provide an important resource for evolutionary genomic studies in Gramineae and facilitate further understanding of molecular mechanisms underlying stress tolerance in monocotyledonous halophytes. The alkaligrass genome data is freely available at http://xhhuanglab.cn/data/alkaligrass.html.
基金This work was supported by the National Natural Science Foundation of China （Nos. 61471270, 51420105002, and 51572199）.
文摘In-plane symmetry is an important contributor to the physical properties of two-dimensional layered materials, as well as atomically thin heterojunctions. Here, we demonstrate anisotropic/isotropic van der Waals （vdW） heterostructures of ReS2 and MoS2 monolayers, where interlayer coupling interactions and charge separation were observed by in situ Raman-photoluminescence spectroscopy, electrical, and photoelectrical measurements. We believe that these results could be helpful for understanding the fundamental physics of atomically thin vdW heterostructures and creating novel electronic and optoelectronic devices.
基金supported by the National Basic Research Program of China(Grant No.2015CB352002)the National Natural Science Foundation of China(Grant No.31770924,61827825,31600692,31470056)+1 种基金the Science Fund for Creative Research Group of China(Grant No.61721092)the Director Fund of the Wuhan National Laboratory for Optoelectronics.
文摘Numerous commercial organic fluorophores with excellent optical properties are precluded from live-cell superresolution imaging due to poor cell permeability.Here,we develop a simple but effective strategy that renders cells permeable to cell-impermeable,organic fluorescent probes by using a novel peptide vehicle,PV-1.By simple coincubation with PV-1,22 different cell-impermeable,organic fluorescent probes were efficiently delivered into live cells and specifically labeled a variety of organelles.Moreover,PV-1 can simultaneously transfer up to three different probes into live cells.By using PV-1 and these cell-impermeable fluorescent probes,we obtained multicolor,longterm,live-cell superresolution images of various organelles,which allowed us to study the dynamic interactions between them.PV-1,together with these organic fluorescent probes,will greatly broaden the applications of superresolution imaging technology in diverse live-cell studies and opens up a new avenue in the design and application of peptide vehicles.
基金Supported by a Grant from the National Basic Research Program of China(973 Program No.2011CB505106)
文摘OBJECTIVE: To investigate the effects of Sini San and fluoxetine on the levels of central and peripheral 5-HT in a rat model of depression, and provide new insight into the treatment of depression with integrated Chinese-Western Medicine.METHODS: A rat model of depression was established by chronic mild stress(CMS). Model rats received either Sini San, fluoxetine, a combination of the two drugs, or no drug treatment. Healthy naive rats were used as controls. Open field and sucrose preference tests were used to assess depression-like behavior. ELISA and immunohistochemistry were used to determine central and peripheral levels of 5-HT.RESULTS: In the group with no drug treatment,central 5-HT expression decreased while peripheral5-HT concentrations increased as CMS continued.Four weeks after CMS, Sini San alone was less effective in reducing depression-like behavior than fluoxetine alone or in combination with Sini San,but combined use was more effective than fluoxetine alone. Eight weeks after CMS, Sini San alone or in combination with fluoxetine was more effective in reducing depression-like behavior than fluoxetine alone. Furthermore Sini San and fluoxetine used alone or in combination notably increased central 5-HT expression and decreased peripheral 5-HT levels in the rat model.CONCLUSION:The results of the present study indicate that there is a synergistic action between the two medicines in the treatment of depression. Sini San exhibited a relatively long lag before its effects were observed; however, by eight weeks the Traditional Chinese Medicine appeared at least as effective as fluoxetine. We suggest that Sini San can replace fluoxetine in the later stages of depression treatment to minimize side effects observed with long-term fluoxetine administration.
基金This work was supported by a grant(2016YFC1302304 to Y.S.)from the Ministry of Science and Technology of Chinaa grant(Z200020 to L.S.)from the Natural Science Foundation of Beijing+1 种基金a grant(QNBJ2020-2 to L.S.)from National Program for Support of Top-notch Young Professionalsgrants(81530073 and 81730079 to Y.S.,31571340 and 81874158 to L.S.,81972659 to W.S.)from the National Natural Science Foundation of China.
文摘The scope and variety of the metabolic intermediates from the mitochondrial tricarboxylic acid(TCA)cycle that are engaged in epigenetic regulation of the chromatin function in the nucleus raise an outstanding question about how timely and precise supply/consumption of these metabolites is achieved in the nucleus.We report here the identification of a nonclassical TCA cycle in the nucleus(nTCA cycle).We found that all the TCA cycle-associated enzymes including citrate synthase(CS),aconitase 2(ACO2),isocitrate dehydrogenase 3(IDH3),oxoglutarate dehydrogenase(OGDH),succinyl-CoA synthetase(SCS),fumarate hydratase(FH),and malate dehydrogenase 2(MDH2),except for succinate dehydrogenase(SDH),a component of electron transport chain for generating ATP,exist in the nucleus.We showed that these nuclear enzymes catalyze an incomplete TCA cycle similar to that found in cyanobacteria.We propose that the nTCA cycle is implemented mainly to generate/consume metabolic intermediates,not for energy production.We demonstrated that the nTCA cycle is intrinsically linked to chromatin dynamics and transcription regulation.Together,our study uncovers the existence of a nonclassical TCA cycle in the nucleus that links the metabolic pathway to epigenetic regulation.
