InSe has emerged as a promising candidate for next-generation electronics due to its predicted ultrahigh electrical performance.However,the efficacy of the InSe transistor in meeting application requirements is hinder...InSe has emerged as a promising candidate for next-generation electronics due to its predicted ultrahigh electrical performance.However,the efficacy of the InSe transistor in meeting application requirements is hindered due to its sensitivity to interfaces.In this study,we have achieved notable enhancement in the electrical performance of InSe transistors through interface engineering.We engineered an InSe/h-BN heterostructure,effectively suppressing dielectric layer-induced scattering.Additionally,we successfully established excellent metal-semiconductor contacts using graphene ribbons as a buffer layer.Through a methodical approach to interface engineering,our graphene/InSe/h-BN transistor demonstrates impressive on-state current,field-effect mobility,and on/off ratio at room temperature,reaching values as high as 1.1 mA/μm,904 cm^(2)·V^(-1)·s^(-1),and>10~6,respectively.Theoretical computations corroborate that the graphene/InSe heterostructure shows significant interlayer charge transfer and weak interlayer interaction,contributing to the enhanced performance of InSe transistors.This research offers a comprehensive strategy to elevate the electrical performance of InSe transistors,paving the way for their utilization in future electronic applications.展开更多
Mechanical strain can induce noteworthy structural and electronic changes in vanadium dioxide, imparting substantial scientific importance to both the exploration of phase transitions and the development of potential ...Mechanical strain can induce noteworthy structural and electronic changes in vanadium dioxide, imparting substantial scientific importance to both the exploration of phase transitions and the development of potential technological applications. Unlike the traditional rutile(R) phase, bronze-phase vanadium dioxide [VO_(2)(B)] exhibits an in-plane anisotropic structure. When subjected to stretching along distinct crystallographic axes, VO_(2)(B) may further manifest the axial dependence in lattice–electron interactions, which is beneficial for gaining insights into the anisotropy of electronic transport.Here, we report an anisotropic room-temperature metal–insulator transition in single-crystal VO_(2)(B) by applying in-situ uniaxial tensile strain. This material exhibits significantly different electromechanical responses along two anisotropic axes.We reveal that such an anisotropic electromechanical response mainly arises from the preferential arrangement of a straininduced unidirectional stripe state in the conductive channel. This insulating stripe state could be attributed to the in-plane dimerization within the distorted zigzag chains of vanadium atoms, evidenced by strain-modulated Raman spectra. Our work may open up a promising avenue for exploiting the anisotropy of metal–insulator transition in vanadium dioxide for potential technological applications.展开更多
Sorghum(Sorghum bicolor(L.)Moench)is a world cereal crop used in China for producing Baijiu,a distilled spirit.We report a telomere-to-telomere genome assembly of the Baijiu cultivar Hongyingzi,HYZ-T2T,using ultralong...Sorghum(Sorghum bicolor(L.)Moench)is a world cereal crop used in China for producing Baijiu,a distilled spirit.We report a telomere-to-telomere genome assembly of the Baijiu cultivar Hongyingzi,HYZ-T2T,using ultralong reads.The 10 chromosome pairs contained 33,462 genes,of which 93%were functionally annotated.The 20 telomeres and 10 centromeric regions on the HYZ-T2T chromosomes were predicted and two consecutive large inversions on chromosome 2 were characterized.A 65-gene reconstruction of the metabolic pathway of tannins,the flavor substances in Baijiu,was performed and may advance the breeding of sorghum cultivars for Baijiu production.展开更多
Detecting tiny deformations or vibrations, particularly those associated with strains below 1%, is essential in various technological applications. Traditional intrinsic materials, including metals and semiconductors,...Detecting tiny deformations or vibrations, particularly those associated with strains below 1%, is essential in various technological applications. Traditional intrinsic materials, including metals and semiconductors, face challenges in simultaneously achieving initial metallic state and strain-induced insulating state, hindering the development of highly sensitive mechanical sensors. Here we report an ultrasensitive mechanical sensor based on a strain-induced tunable ordered array of metallic and insulating states in the single-crystal bronze-phase vanadium dioxide [VO_(2)(B)] quantum material. It is shown that the initial metallic state in the VO_(2)(B) flake can be tuned to the insulating state by applying a weak uniaxial tensile strain. Such a unique property gives rise to a record-high gauge factor of above 607970, surpassing previous values by an order of magnitude, with excellent linearity and mechanical resilience as well as durability. As a proof-of-concept application, we use our proposed mechanical sensor to demonstrate precise sensing of the micro piece, gentle airflows and water droplets. We attribute the superior performance of the sensor to the strain-induced continuous metal-insulator transition in the single-crystal VO_(2)(B) flake, evidenced by experimental and simulation results. Our findings highlight the potential of exploiting correlated quantum materials for next-generation ultrasensitive flexible mechanical sensors, addressing critical limitations in traditional materials.展开更多
Icing can significantly change the geometric parameters of wind turbine blades,which in turn,can reduce the aerodynamic characteristics of the airfoil.In-depth research is conducted in this study to identify the reaso...Icing can significantly change the geometric parameters of wind turbine blades,which in turn,can reduce the aerodynamic characteristics of the airfoil.In-depth research is conducted in this study to identify the reasons for the decline of wind power equipment performance through the icing process.An accurate experimental test method is proposed in a natural environment that examines the growth and distribution of ice formation over the airfoil profile.The mathematical models of the airfoil chord length,camber,and thickness are established in order to investigate the variation of geometric airfoil parameters under different icing states.The results show that ice accumulation varies considerably along the blade span.By environmental temperature drop,the minimum and maximum extents of ice accumulation are observed near the blade root(0.2 R)and the blade tip(0.95 R),respectively(R represents the blade length).The icing process steadily increases the chord length and decreases the airfoil curvature,reaching the largest value at the blade tip region.Furthermore,the maximum curvature is reduced to 41.50%of the original curvature.The maximum camber position of the airfoil moves towards the trailing edge,and the most prominent position occurs at the middle blade region(0.6 R),where it moves back by 19.43%.Ice accumulation steadily increases airfoil thickness.It leads to the maximum thickness growth of 53.40%that occurs at the blade tip region and moves forward to the leading edge by 10%.The research results can provide the required theoretical support for further monitoring the blades operating conditions to ensure reliable wind turbines’operation.展开更多
With the continuous increase in the proportional use of wind energy across the globe,the reduction of power generation efficiency and safety hazards caused by the icing on wind turbine blades have attracted more consi...With the continuous increase in the proportional use of wind energy across the globe,the reduction of power generation efficiency and safety hazards caused by the icing on wind turbine blades have attracted more consideration for research.Therefore,it is crucial to accurately analyze the thickness of icing on wind turbine blades,which can serve as a basis for formulating corresponding control measures and ensure a safe and stable operation of wind turbines in winter times and/or in high altitude areas.This paper fully utilized the advantages of the support vector machine(SVM)and back-propagation neural network(BPNN),with the incorporation of particle swarm optimization(PSO)algorithms to optimize the parameters of the SVM.The paper proposes a hybrid assessment model of PSO-SVM and BPNN based on dynamic weighting rules.Three sets of icing data under a rotating working state of the wind turbine were used as examples for model verification.Based on a comparative analysis with other models,the results showed that the proposed model has better accuracy and stability in analyzing the icing on wind turbine blades.展开更多
Reservoir computing has been considered as a promising intelligent computing paradigm for effectively processing complex temporal information.Exploiting tunable and reproducible dynamics in the single electronic devic...Reservoir computing has been considered as a promising intelligent computing paradigm for effectively processing complex temporal information.Exploiting tunable and reproducible dynamics in the single electronic device have been desired to implement the “reservoir” and the “readout” layer of reservoir computing system.Two-dimensional moiré materials,with an artificial lattice constant many times larger than the atomic length scale,are one type of most studied artificial quantum materials in community of material science and condensed-matter physics over the past years.These materials are featured with gate-tunable periodic potential and electronic correlation,thus varying the electric field allows the electrons in the moiré potential per unit cell to exhibit distinct and reproducible dynamics,showing great promise in robust reservoir computing.Here,we report that a moiré synaptic transistor can be used to implement the reservoir computing system with a homogeneous reservoir-readout architecture.The synaptic transistor is fabricated based on an h-BN/bilayer graphene/h-BN moiré heterostructure,exhibiting ferroelectricity-like hysteretic gate voltage dependence of resistance.Varying the magnitude of the gate voltage enables the moiré transistor to switch between long-term memory and shortterm memory with nonlinear dynamics.By employing the short-and long-term memories as the reservoir nodes and weights of the readout layer,respectively,we construct a full-moiré physical neural network and demonstrate that the classification accuracy of 90.8% can be achieved for the MNIST(Modified National Institute of Standards and Technology) handwritten digits database.Our work would pave the way towards the development of neuromorphic computing based on moiré materials.展开更多
Moiré heterostructures, where the constituent 2D materials are stacked vertically at a small angle, feature longwavelength interference pattern at the van der Waals interfaces. One typical example is twisted bila...Moiré heterostructures, where the constituent 2D materials are stacked vertically at a small angle, feature longwavelength interference pattern at the van der Waals interfaces. One typical example is twisted bilayer graphene. In this moiré heterostructure, the emergence of moiré superlattices can effectively reconstruct the energy bands into dispersionless flat bands at a special twisted angle(so-called ‘magic angle’).展开更多
Some trace elements(TEs),both bio-essential and redox-sensitive,are promising tracers of Earth’s surface processes.As an essential sedimentary organic matter,kerogen may have inherited and retained the key TEs from o...Some trace elements(TEs),both bio-essential and redox-sensitive,are promising tracers of Earth’s surface processes.As an essential sedimentary organic matter,kerogen may have inherited and retained the key TEs from organisms.In this study,the distribution of TEs in kerogens from two sections(Dongkanshang and Fengtan) in South China was analyzed to explore its biogeochemical significance during Ediacaran-Lower Cambrian.Compared with V and Zn,the relative concentrations of Co,Ni,Cu,and Mo were generally higher in kerogens than in the whole rocks.Enrichment of TEs in the kerogen was involved in the selective utilization of TEs by different organic precursors and the competition of sulfide in the depositional environment.The significant content of TEs in the kerogens from deep-water facies corresponded to a more negative δ^(13) Ckeras a result of the dominant taxa of chemo autotrophs with tremendous bioaccumulation potential for trace metals and the reduction conditions favorable for organic matter preservation.Furthermore,the content variations of trace elements in the kerogens coincided with the rise and fall of the Ediacaran biota,implying that the trace elements might have played an important role in early life evolution.展开更多
Several Chinese marine satellites have been launched in recent years.Monitoring sea ice and the ocean in the Arctic is of great importance for climate research.Sea ice in the Arctic has changed rapidly during the past...Several Chinese marine satellites have been launched in recent years.Monitoring sea ice and the ocean in the Arctic is of great importance for climate research.Sea ice in the Arctic has changed rapidly during the past few decades with respect to the extent and thickness.In this study,we applied combined passive and active microwave data from the Chinese HaiYang-2B(HY-2B)satellite to classify ice and sea water in the Arctic.We use data from a radar altimeter(RA)and a calibration microwave radiometer(CMR)to discriminate between ice and water by applying several approaches(1)the single parameter threshold criteria,(2)the multi-parameters linear segmentations and(3)the K-means clustering.The results yielded by these methods were in good agreement(classification accuracy>95%)with the Satellite Application Facility on Ocean and Sea Ice products between November and April.For other months(May–October),however,the agreement was less good(lowest classification accuracy approximate 85%in summer).A hybrid approach combined with graphical ice edges detection and microwave radar waveform analysis is therefore developed.A visual comparison with SAR images suggested the hybrid approach results greatly improved the ice and water discrimination in summer.This study demonstrated that multi-sensors(RA and CMR)configurations from HY satellites can offer comparable polar earth observation to the European Space Agency and NOAA satellite products.展开更多
With regard to the rapid growth of China’s building area and the increasing energy consumption of buildings, green buildings have become an important issue for balancing economic development and environmental impact....With regard to the rapid growth of China’s building area and the increasing energy consumption of buildings, green buildings have become an important issue for balancing economic development and environmental impact. However, the current evaluation systems for various types of green buildings are often unable to achieve a set of standards in practice due to the distinct regional characteristics of each region. Therefore, in view of the regional characteristics of the climate, terrain, ecology, and economic development in the cold regions of Sichuan, it is important to study the evaluation system of green residential buildings suitable for the cold regions of Sichuan. This article focuses on the regional characteristics of climate, topography, ecology, and economic development in the cold regions of Sichuan, and discusses the limitations of the current standards on the practice of green building in cold regions of Sichuan through a sociological questionnaire survey on the comfort of living in the local population. Then from the two dimensions of the advantages of traditional houses and the particularity of national culture, the strategies for the optimization and improvement of the evaluation index system for green residential buildings in the cold regions of Sichuan were proposed. After comprehensively considering the factors that affect the green residential buildings, including the regional characteristics of the cold regions of Sichuan, and the green performance of buildings, local characteristics and ethnic features were included in the evaluation system. The evaluation index system of green residential buildings in the cold regions of Sichuan, consists of 92 three-level indicators. A professional hierarchical analysis software yaahp was used to establish a multi-level hierarchical model between the indicators, and the indicators were compared with each other layer by layer to clarify the importance of the indicators. Based on this, a judgment matrix for each layer was constructed and obtained. The weight of each indicator is accurate, and the scoring mechanism and grading standards are constructed according to it. Through the calculation, the consistency test of the entire model was passed, thereby confirming the scientificity and rationality of the entire evaluation system.展开更多
One of the factors for the evaluation of the space environment is the comfort of outdoor activities spaces in urban parks. The space composed of different landscape elements has different microclimate environment. In ...One of the factors for the evaluation of the space environment is the comfort of outdoor activities spaces in urban parks. The space composed of different landscape elements has different microclimate environment. In this paper, in order to evaluate the role of thermal comfort in influencing resident’s assessment of the outdoor space and activities of the park, a thermal comfort survey was conducted on the outdoor open space of Mianyang Urban Park in summer. In this article, meteorological surveys, questionnaire surveys and observation of park attendance are selected to collect data. The physiological equivalent temperature (PET) assessment was selected as the index to evaluate resident’s thermal comfort level, and the comprehensive evaluation and analysis of the spatial thermal environment of different outdoor landscape elements in the park. The overall comfort of current visitors is mainly influenced by their subjective heat perception voting (TSV). In this article, we focus on providing microclimate adjustment considerations for urban park landscape design, and may help people understand the outdoor thermal comfort of Mianyang in summer, increase the using time of outdoor activities, and promote the use of outdoor space.展开更多
AIM:To investigate the function of microRNA-143(miR-143)in gastric cancer and explore the target genes of miR-143.METHODS:A quantitative real-time reverse transcription-polymerase chain reaction(RT-PCR)analysis was pe...AIM:To investigate the function of microRNA-143(miR-143)in gastric cancer and explore the target genes of miR-143.METHODS:A quantitative real-time reverse transcription-polymerase chain reaction(RT-PCR)analysis was performed to evaluate miR-143 expression in gastric cancer cell lines.After transfecting gastric cancer cells with miR-143-5p and miR-143-3p precursors,Alamar blue and apoptosis assays were used to measure the respective proliferation and apoptosis rates.Cyclooxygenase-2(COX-2)expression was determined by realtime RT-PCR and Western blot assays after miR-143transfection.Reporter plasmids were constructed,and a luciferase reporter assay was used to identify the miR-143 binding site on COX-2.RESULTS:Both miR-143-5p and miR-143-3p were significantly downregulated in multiple gastric cancer cell lines.Forced miR-143-5p and miR-143-3p expression in gastric cancer cells produced a profound cytotoxic effect.MiR-145-5p transfection into gastric cancer cells resulted in a greater growth inhibitory effect(61.23%±3.16%vs 46.58%±4.28%,P<0.05 in the MKN-1cell line)and a higher apoptosis rate(28.74%±1.93%vs 22.13%±3.31%,P<0.05 in the MKN-1 cell line)than miR-143-3p transfection.Further analysis indicated that COX-2 expression was potently suppressed by miR-143-5p but not by miR-143-3p.The activity of a luciferase reporter construct that contained the 3’-untranslated region(UTR)of COX-2 was downregulated by miR-143-5p(43.6%±4.86%,P<0.01)but not by miR-143-3p.A mutation in the miR-145-5p binding site completely ablated the regulatory effect on luciferase activity,which suggests that there is a direct miR-145-5p binding site in the 3’-UTR of COX-2.CONCLUSION:Both miR-143-5p and miR-143-3p function as anti-oncomirs in gastric cancer.However,miR-143-5p alone directly targets COX-2,and it exhibits a stronger tumor suppressive effect than miR-143-3p.展开更多
Tertiary lymphoid structures(TLS)are ectopic lymphoid structures in cancers that are largely associated with favourable prognosis.However,the prognostic value of TLSs in oral squamous cell carcinoma(OSCC)is largely un...Tertiary lymphoid structures(TLS)are ectopic lymphoid structures in cancers that are largely associated with favourable prognosis.However,the prognostic value of TLSs in oral squamous cell carcinoma(OSCC)is largely unknown,and the association between tumour infiltrating lymphocytes(TILs)and TLSs has been rarely explored in OSCC.In this study,associated markers of TLS,including peripheral node address(PNAd)in high endothelial venules,CD20 in B cells and CD3 in T cells,were examined in 168 OSCC patients,and survival analysis was performed between TLS-positive and TLS-negative cohorts.We detected the presence of TILs by staining CD8+cytotoxic T cells and CD57+NK cells as well.TLSs appeared as highly organized structures in 45(26.8%)cases.TLSpositive patients had a better 5-year overall survival(OS)rate(88.9%vs.56.1%,P<0.001)and relapse-free survival(RFS)rate(88.9%vs.63.4%,P=0.002).Moreover,the presence of TLS was an independent prognostic factor for both the 5-year OS rate(hazard ratio[HR]=3.784;95%confidence interval[CI],1.498–9.562)and RFS rate(HR=3.296;95%CI,1.279–8.490)in multivariate analysis.Furthermore,a higher density of CD8+T cells and CD57+NK cells was found in TLS-positive sections than in TLS-negative counterparts(P<0.001),and their combination provided a higher predictive accuracy(AUC=0.730;95%CI,0.654–0.805).In conclusion,our results suggest that TLS is an independent positive prognostic factor for OSCC patients.These findings provide a theoretical basis for the future diagnostic and therapeutic value of TLSs in OSCC treatment.展开更多
Very little is known about the role of melatonin in the trigeminal system, including the function of melatonin receptor 1. In the present study, adult rats were injected with formaldehyde into the right vibrissae pad ...Very little is known about the role of melatonin in the trigeminal system, including the function of melatonin receptor 1. In the present study, adult rats were injected with formaldehyde into the right vibrissae pad to establish a model of orofacial inflammatory pain. The distribution of melatonin re- ceptor 1 and nicotinamide adenine dinucleotide phosphate diaphorase in the caudal spinal trigeminal nucleus and trigeminal ganglion was determined with immunohistochemistry and histo- chemistry. The results show that there are significant differences in melatonin receptor 1 expression and nicotinamide adenine dinucleotide phosphate diaphorase expression in the trigeminal ganglia and caudal spinal nucleus during the early stage of orofacial inflammatory pain. Our findings sug- gest that when melatonin receptor 1 expression in the caudal spinal nucleus is significantly reduced, melatonin's regulatory effect on pain is attenuated.展开更多
Annual observations of first-year ice(FYI) and second-year ice(SYI) near Zhongshan Station, East Antarctica,were conducted for the first time from December 2011 to December 2012. Melt ponds appeared from early Decembe...Annual observations of first-year ice(FYI) and second-year ice(SYI) near Zhongshan Station, East Antarctica,were conducted for the first time from December 2011 to December 2012. Melt ponds appeared from early December 2011. Landfast ice partly broke in late January, 2012 after a strong cyclone. Open water was refrozen to form new ice cover in mid-February, and then FYI and SYI co-existed in March with a growth rate of 0.8 cm/d for FYI and a melting rate of 2.7 cm/d for SYI. This difference was due to the oceanic heat flux and the thickness of ice,with weaker heat flux through thicker ice. From May onward, FYI and SYI showed a similar growth by 0.5 cm/d.Their maximum thickness reached 160.5 cm and 167.0 cm, respectively, in late October. Drillings showed variations of FYI thickness to be generally less than 1.0 cm, but variations were up to 33.0 cm for SYI in March,suggesting that the SYI bottom was particularly uneven. Snow distribution was strongly affected by wind and surface roughness, leading to large thickness differences in the different sites. Snow and ice thickness in Nella Fjord had a similar "east thicker, west thinner" spatial distribution. Easterly prevailing wind and local topography led to this snow pattern. Superimposed ice induced by snow cover melting in summer thickened multi-year ice,causing it to be thicker than the snow-free SYI. The estimated monthly oceanic heat flux was ~30.0 W/m2 in March–May, reducing to ~10.0 W/m2 during July–October, and increasing to ~15.0 W/m2 in November. The seasonal change and mean value of 15.6 W/m2 was similar to the findings of previous research. The results can be used to further our understanding of landfast ice for climate change study and Chinese Antarctic Expedition services.展开更多
Mesenchymal stem cells(MSCs)have been widely exploited as promising candidates in clinical settings for bone repair and regeneration in view of their self-renewal capacity and multipotentiality.However,little is known...Mesenchymal stem cells(MSCs)have been widely exploited as promising candidates in clinical settings for bone repair and regeneration in view of their self-renewal capacity and multipotentiality.However,little is known about the mechanisms underlying their fate determination,which would illustrate their effectiveness in regenerative medicine.Recent evidence has shed light on a fundamental biological role of autophagy in the maintenance of the regenerative capability of MSCs and bone homeostasis.Autophagy has been implicated in provoking an immediately available cytoprotective mechanism in MSCs against stress,while dysfunction of autophagy impairs the function of MSCs,leading to imbalances of bone remodeling and a wide range of aging and degenerative bone diseases.This review aims to summarize the up-to-date knowledge about the effects of autophagy on MSC fate determination and its role as a stress adaptation response.Meanwhile,we highlight autophagy as a dynamic process and a double-edged sword to account for some discrepancies in the current research.We also discuss the contribution of autophagy to the regulation of bone cells and bone remodeling and emphasize its potential involvement in bone disease.展开更多
The crude oils typically from the CambrianLower Ordovician source rocks of Tarim Basin, NW"China, such as TD2 and TZ62S, are13C-enriched with the stable carbon isotopic ratios(VPDB) approaching-28 %.In this paper...The crude oils typically from the CambrianLower Ordovician source rocks of Tarim Basin, NW"China, such as TD2 and TZ62S, are13C-enriched with the stable carbon isotopic ratios(VPDB) approaching-28 %.In this paper, the main research viewpoints on this issue are summarized, and combined with results from organic and inorganic carbon isotope stratum curves of the outcrop at the Ya'erdang Mountain in Tarim Basin. In addition, more alternative interpretations are discussed. On one hand, the inverse fractionation features of stable carbon and hydrogen isotopes of these crude oils may imply their protogenous nature. On the other hand, the anisotropy of source rocks and contribution from older stratum source rocks need verifying as well. For the sake of the final resolution of this issue, some further study topics are recommended.展开更多
基金the support of the National Natural Science Foundation of China (Grant No.62204030)supported in part by the National Natural Science Foundation of China (Grant Nos.62122036,62034004,61921005,61974176,and 12074176)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDB44000000)。
文摘InSe has emerged as a promising candidate for next-generation electronics due to its predicted ultrahigh electrical performance.However,the efficacy of the InSe transistor in meeting application requirements is hindered due to its sensitivity to interfaces.In this study,we have achieved notable enhancement in the electrical performance of InSe transistors through interface engineering.We engineered an InSe/h-BN heterostructure,effectively suppressing dielectric layer-induced scattering.Additionally,we successfully established excellent metal-semiconductor contacts using graphene ribbons as a buffer layer.Through a methodical approach to interface engineering,our graphene/InSe/h-BN transistor demonstrates impressive on-state current,field-effect mobility,and on/off ratio at room temperature,reaching values as high as 1.1 mA/μm,904 cm^(2)·V^(-1)·s^(-1),and>10~6,respectively.Theoretical computations corroborate that the graphene/InSe heterostructure shows significant interlayer charge transfer and weak interlayer interaction,contributing to the enhanced performance of InSe transistors.This research offers a comprehensive strategy to elevate the electrical performance of InSe transistors,paving the way for their utilization in future electronic applications.
基金Project supported by the National Key R&D Program of China (Grant No. 2023YFF1203600)the National Natural Science Foundation of China (Grant Nos. 62122036, 62034004, 12322407, 61921005, and 12074176)+1 种基金the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No. XDB44000000)supported by the program for Outstanding Ph D Candidates of Nanjing University。
文摘Mechanical strain can induce noteworthy structural and electronic changes in vanadium dioxide, imparting substantial scientific importance to both the exploration of phase transitions and the development of potential technological applications. Unlike the traditional rutile(R) phase, bronze-phase vanadium dioxide [VO_(2)(B)] exhibits an in-plane anisotropic structure. When subjected to stretching along distinct crystallographic axes, VO_(2)(B) may further manifest the axial dependence in lattice–electron interactions, which is beneficial for gaining insights into the anisotropy of electronic transport.Here, we report an anisotropic room-temperature metal–insulator transition in single-crystal VO_(2)(B) by applying in-situ uniaxial tensile strain. This material exhibits significantly different electromechanical responses along two anisotropic axes.We reveal that such an anisotropic electromechanical response mainly arises from the preferential arrangement of a straininduced unidirectional stripe state in the conductive channel. This insulating stripe state could be attributed to the in-plane dimerization within the distorted zigzag chains of vanadium atoms, evidenced by strain-modulated Raman spectra. Our work may open up a promising avenue for exploiting the anisotropy of metal–insulator transition in vanadium dioxide for potential technological applications.
基金supported by the Scientific Research Project of Kweichow Moutai Liquor Co.,Ltd.(MTGF2023007)the National Natural Science Foundation of China(32160459,32172036)+2 种基金the Guizhou Natural Science Foundation of China(QKHJC[2023]YB169)the Innovation Capacity Building Project of Guizhou Scientific Institutions(QKFQ[2022]007])the Guizhou Academy of Agricultural Sciences Project(Guizhou Agricultural Germplasm Resources(2023)06)。
文摘Sorghum(Sorghum bicolor(L.)Moench)is a world cereal crop used in China for producing Baijiu,a distilled spirit.We report a telomere-to-telomere genome assembly of the Baijiu cultivar Hongyingzi,HYZ-T2T,using ultralong reads.The 10 chromosome pairs contained 33,462 genes,of which 93%were functionally annotated.The 20 telomeres and 10 centromeric regions on the HYZ-T2T chromosomes were predicted and two consecutive large inversions on chromosome 2 were characterized.A 65-gene reconstruction of the metabolic pathway of tannins,the flavor substances in Baijiu,was performed and may advance the breeding of sorghum cultivars for Baijiu production.
基金supported in part by the National Key R&D Program of China (Grant Nos.2023YFF1203600 and 2023YFF0718400)the National Natural Science Foundation of China (Grant Nos.62122036,12322407,62034004,61921005,and 12074176)+2 种基金the Leading-edge Technology Program of Jiangsu Natural Science Foundation (Grant No.BK20232004)the Strategic Priority Research Program of the Chinese Academy of Sciences (Grant No.XDB44000000)support from the AIQ Foundation and the eScience Center of Collaborative Innovation Center of Advanced Microstructures。
文摘Detecting tiny deformations or vibrations, particularly those associated with strains below 1%, is essential in various technological applications. Traditional intrinsic materials, including metals and semiconductors, face challenges in simultaneously achieving initial metallic state and strain-induced insulating state, hindering the development of highly sensitive mechanical sensors. Here we report an ultrasensitive mechanical sensor based on a strain-induced tunable ordered array of metallic and insulating states in the single-crystal bronze-phase vanadium dioxide [VO_(2)(B)] quantum material. It is shown that the initial metallic state in the VO_(2)(B) flake can be tuned to the insulating state by applying a weak uniaxial tensile strain. Such a unique property gives rise to a record-high gauge factor of above 607970, surpassing previous values by an order of magnitude, with excellent linearity and mechanical resilience as well as durability. As a proof-of-concept application, we use our proposed mechanical sensor to demonstrate precise sensing of the micro piece, gentle airflows and water droplets. We attribute the superior performance of the sensor to the strain-induced continuous metal-insulator transition in the single-crystal VO_(2)(B) flake, evidenced by experimental and simulation results. Our findings highlight the potential of exploiting correlated quantum materials for next-generation ultrasensitive flexible mechanical sensors, addressing critical limitations in traditional materials.
基金supported by a grant of National Natural Science Foundation of China,Grant No.51665052.
文摘Icing can significantly change the geometric parameters of wind turbine blades,which in turn,can reduce the aerodynamic characteristics of the airfoil.In-depth research is conducted in this study to identify the reasons for the decline of wind power equipment performance through the icing process.An accurate experimental test method is proposed in a natural environment that examines the growth and distribution of ice formation over the airfoil profile.The mathematical models of the airfoil chord length,camber,and thickness are established in order to investigate the variation of geometric airfoil parameters under different icing states.The results show that ice accumulation varies considerably along the blade span.By environmental temperature drop,the minimum and maximum extents of ice accumulation are observed near the blade root(0.2 R)and the blade tip(0.95 R),respectively(R represents the blade length).The icing process steadily increases the chord length and decreases the airfoil curvature,reaching the largest value at the blade tip region.Furthermore,the maximum curvature is reduced to 41.50%of the original curvature.The maximum camber position of the airfoil moves towards the trailing edge,and the most prominent position occurs at the middle blade region(0.6 R),where it moves back by 19.43%.Ice accumulation steadily increases airfoil thickness.It leads to the maximum thickness growth of 53.40%that occurs at the blade tip region and moves forward to the leading edge by 10%.The research results can provide the required theoretical support for further monitoring the blades operating conditions to ensure reliable wind turbines’operation.
基金supported by the Natural Science Foundation of China(Project No.51665052).
文摘With the continuous increase in the proportional use of wind energy across the globe,the reduction of power generation efficiency and safety hazards caused by the icing on wind turbine blades have attracted more consideration for research.Therefore,it is crucial to accurately analyze the thickness of icing on wind turbine blades,which can serve as a basis for formulating corresponding control measures and ensure a safe and stable operation of wind turbines in winter times and/or in high altitude areas.This paper fully utilized the advantages of the support vector machine(SVM)and back-propagation neural network(BPNN),with the incorporation of particle swarm optimization(PSO)algorithms to optimize the parameters of the SVM.The paper proposes a hybrid assessment model of PSO-SVM and BPNN based on dynamic weighting rules.Three sets of icing data under a rotating working state of the wind turbine were used as examples for model verification.Based on a comparative analysis with other models,the results showed that the proposed model has better accuracy and stability in analyzing the icing on wind turbine blades.
基金supported in part by the National Natural Science Foundation of China(Grant Nos.62122036,12322407,62034004,61921005,12074176,and 61974176)the Strategic Priority Research Program of the Chinese Academy of Sciences(Grant No.XDB44000000)+1 种基金the Fundamental Research Funds for the Central Universities(Grant Nos.020414380203 and 020414380179)the support from the AIQ foundation。
文摘Reservoir computing has been considered as a promising intelligent computing paradigm for effectively processing complex temporal information.Exploiting tunable and reproducible dynamics in the single electronic device have been desired to implement the “reservoir” and the “readout” layer of reservoir computing system.Two-dimensional moiré materials,with an artificial lattice constant many times larger than the atomic length scale,are one type of most studied artificial quantum materials in community of material science and condensed-matter physics over the past years.These materials are featured with gate-tunable periodic potential and electronic correlation,thus varying the electric field allows the electrons in the moiré potential per unit cell to exhibit distinct and reproducible dynamics,showing great promise in robust reservoir computing.Here,we report that a moiré synaptic transistor can be used to implement the reservoir computing system with a homogeneous reservoir-readout architecture.The synaptic transistor is fabricated based on an h-BN/bilayer graphene/h-BN moiré heterostructure,exhibiting ferroelectricity-like hysteretic gate voltage dependence of resistance.Varying the magnitude of the gate voltage enables the moiré transistor to switch between long-term memory and shortterm memory with nonlinear dynamics.By employing the short-and long-term memories as the reservoir nodes and weights of the readout layer,respectively,we construct a full-moiré physical neural network and demonstrate that the classification accuracy of 90.8% can be achieved for the MNIST(Modified National Institute of Standards and Technology) handwritten digits database.Our work would pave the way towards the development of neuromorphic computing based on moiré materials.
基金supported in part by the National Natural Science Foundation of China(62122036,62034004,61921005,12074176 and 61974176)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB44000000)the Fundamental Research Funds for the Central Universities(020414380203,020414380179)。
文摘Moiré heterostructures, where the constituent 2D materials are stacked vertically at a small angle, feature longwavelength interference pattern at the van der Waals interfaces. One typical example is twisted bilayer graphene. In this moiré heterostructure, the emergence of moiré superlattices can effectively reconstruct the energy bands into dispersionless flat bands at a special twisted angle(so-called ‘magic angle’).
基金financially supported by the National Natural Science Foundation of China (42072145)the National Oil and Gas Special Project of China (2017ZX05008002)。
文摘Some trace elements(TEs),both bio-essential and redox-sensitive,are promising tracers of Earth’s surface processes.As an essential sedimentary organic matter,kerogen may have inherited and retained the key TEs from organisms.In this study,the distribution of TEs in kerogens from two sections(Dongkanshang and Fengtan) in South China was analyzed to explore its biogeochemical significance during Ediacaran-Lower Cambrian.Compared with V and Zn,the relative concentrations of Co,Ni,Cu,and Mo were generally higher in kerogens than in the whole rocks.Enrichment of TEs in the kerogen was involved in the selective utilization of TEs by different organic precursors and the competition of sulfide in the depositional environment.The significant content of TEs in the kerogens from deep-water facies corresponded to a more negative δ^(13) Ckeras a result of the dominant taxa of chemo autotrophs with tremendous bioaccumulation potential for trace metals and the reduction conditions favorable for organic matter preservation.Furthermore,the content variations of trace elements in the kerogens coincided with the rise and fall of the Ediacaran biota,implying that the trace elements might have played an important role in early life evolution.
基金The National Key Research and Development Program of China under contract Nos 2021YFC2803300,2018YFC1407200,2016YFC1401000 and 2018YFC1407203the Impact and Response of Antarctic Seas to Climate Change,IRASCC2020-2022 under contract No.01-01-03+1 种基金the National Natural Science Foundation of China under contract Nos 41876204,41941008,41941013 and 41630969the Key Special Project for Introduced Talents Team of Southern Marine Science and Engineering Guangdong Laboratory(Guangzhou)under contract No.GML2019ZD0302.
文摘Several Chinese marine satellites have been launched in recent years.Monitoring sea ice and the ocean in the Arctic is of great importance for climate research.Sea ice in the Arctic has changed rapidly during the past few decades with respect to the extent and thickness.In this study,we applied combined passive and active microwave data from the Chinese HaiYang-2B(HY-2B)satellite to classify ice and sea water in the Arctic.We use data from a radar altimeter(RA)and a calibration microwave radiometer(CMR)to discriminate between ice and water by applying several approaches(1)the single parameter threshold criteria,(2)the multi-parameters linear segmentations and(3)the K-means clustering.The results yielded by these methods were in good agreement(classification accuracy>95%)with the Satellite Application Facility on Ocean and Sea Ice products between November and April.For other months(May–October),however,the agreement was less good(lowest classification accuracy approximate 85%in summer).A hybrid approach combined with graphical ice edges detection and microwave radar waveform analysis is therefore developed.A visual comparison with SAR images suggested the hybrid approach results greatly improved the ice and water discrimination in summer.This study demonstrated that multi-sensors(RA and CMR)configurations from HY satellites can offer comparable polar earth observation to the European Space Agency and NOAA satellite products.
文摘With regard to the rapid growth of China’s building area and the increasing energy consumption of buildings, green buildings have become an important issue for balancing economic development and environmental impact. However, the current evaluation systems for various types of green buildings are often unable to achieve a set of standards in practice due to the distinct regional characteristics of each region. Therefore, in view of the regional characteristics of the climate, terrain, ecology, and economic development in the cold regions of Sichuan, it is important to study the evaluation system of green residential buildings suitable for the cold regions of Sichuan. This article focuses on the regional characteristics of climate, topography, ecology, and economic development in the cold regions of Sichuan, and discusses the limitations of the current standards on the practice of green building in cold regions of Sichuan through a sociological questionnaire survey on the comfort of living in the local population. Then from the two dimensions of the advantages of traditional houses and the particularity of national culture, the strategies for the optimization and improvement of the evaluation index system for green residential buildings in the cold regions of Sichuan were proposed. After comprehensively considering the factors that affect the green residential buildings, including the regional characteristics of the cold regions of Sichuan, and the green performance of buildings, local characteristics and ethnic features were included in the evaluation system. The evaluation index system of green residential buildings in the cold regions of Sichuan, consists of 92 three-level indicators. A professional hierarchical analysis software yaahp was used to establish a multi-level hierarchical model between the indicators, and the indicators were compared with each other layer by layer to clarify the importance of the indicators. Based on this, a judgment matrix for each layer was constructed and obtained. The weight of each indicator is accurate, and the scoring mechanism and grading standards are constructed according to it. Through the calculation, the consistency test of the entire model was passed, thereby confirming the scientificity and rationality of the entire evaluation system.
文摘One of the factors for the evaluation of the space environment is the comfort of outdoor activities spaces in urban parks. The space composed of different landscape elements has different microclimate environment. In this paper, in order to evaluate the role of thermal comfort in influencing resident’s assessment of the outdoor space and activities of the park, a thermal comfort survey was conducted on the outdoor open space of Mianyang Urban Park in summer. In this article, meteorological surveys, questionnaire surveys and observation of park attendance are selected to collect data. The physiological equivalent temperature (PET) assessment was selected as the index to evaluate resident’s thermal comfort level, and the comprehensive evaluation and analysis of the spatial thermal environment of different outdoor landscape elements in the park. The overall comfort of current visitors is mainly influenced by their subjective heat perception voting (TSV). In this article, we focus on providing microclimate adjustment considerations for urban park landscape design, and may help people understand the outdoor thermal comfort of Mianyang in summer, increase the using time of outdoor activities, and promote the use of outdoor space.
文摘AIM:To investigate the function of microRNA-143(miR-143)in gastric cancer and explore the target genes of miR-143.METHODS:A quantitative real-time reverse transcription-polymerase chain reaction(RT-PCR)analysis was performed to evaluate miR-143 expression in gastric cancer cell lines.After transfecting gastric cancer cells with miR-143-5p and miR-143-3p precursors,Alamar blue and apoptosis assays were used to measure the respective proliferation and apoptosis rates.Cyclooxygenase-2(COX-2)expression was determined by realtime RT-PCR and Western blot assays after miR-143transfection.Reporter plasmids were constructed,and a luciferase reporter assay was used to identify the miR-143 binding site on COX-2.RESULTS:Both miR-143-5p and miR-143-3p were significantly downregulated in multiple gastric cancer cell lines.Forced miR-143-5p and miR-143-3p expression in gastric cancer cells produced a profound cytotoxic effect.MiR-145-5p transfection into gastric cancer cells resulted in a greater growth inhibitory effect(61.23%±3.16%vs 46.58%±4.28%,P<0.05 in the MKN-1cell line)and a higher apoptosis rate(28.74%±1.93%vs 22.13%±3.31%,P<0.05 in the MKN-1 cell line)than miR-143-3p transfection.Further analysis indicated that COX-2 expression was potently suppressed by miR-143-5p but not by miR-143-3p.The activity of a luciferase reporter construct that contained the 3’-untranslated region(UTR)of COX-2 was downregulated by miR-143-5p(43.6%±4.86%,P<0.01)but not by miR-143-3p.A mutation in the miR-145-5p binding site completely ablated the regulatory effect on luciferase activity,which suggests that there is a direct miR-145-5p binding site in the 3’-UTR of COX-2.CONCLUSION:Both miR-143-5p and miR-143-3p function as anti-oncomirs in gastric cancer.However,miR-143-5p alone directly targets COX-2,and it exhibits a stronger tumor suppressive effect than miR-143-3p.
基金This work was supported by the National Natural Science Foundations of China(Nos.81972532,81772896,81602383 and 81472524)the Science and Technology Planning Project of Guangzhou City of China(No.2017004020102).
文摘Tertiary lymphoid structures(TLS)are ectopic lymphoid structures in cancers that are largely associated with favourable prognosis.However,the prognostic value of TLSs in oral squamous cell carcinoma(OSCC)is largely unknown,and the association between tumour infiltrating lymphocytes(TILs)and TLSs has been rarely explored in OSCC.In this study,associated markers of TLS,including peripheral node address(PNAd)in high endothelial venules,CD20 in B cells and CD3 in T cells,were examined in 168 OSCC patients,and survival analysis was performed between TLS-positive and TLS-negative cohorts.We detected the presence of TILs by staining CD8+cytotoxic T cells and CD57+NK cells as well.TLSs appeared as highly organized structures in 45(26.8%)cases.TLSpositive patients had a better 5-year overall survival(OS)rate(88.9%vs.56.1%,P<0.001)and relapse-free survival(RFS)rate(88.9%vs.63.4%,P=0.002).Moreover,the presence of TLS was an independent prognostic factor for both the 5-year OS rate(hazard ratio[HR]=3.784;95%confidence interval[CI],1.498–9.562)and RFS rate(HR=3.296;95%CI,1.279–8.490)in multivariate analysis.Furthermore,a higher density of CD8+T cells and CD57+NK cells was found in TLS-positive sections than in TLS-negative counterparts(P<0.001),and their combination provided a higher predictive accuracy(AUC=0.730;95%CI,0.654–0.805).In conclusion,our results suggest that TLS is an independent positive prognostic factor for OSCC patients.These findings provide a theoretical basis for the future diagnostic and therapeutic value of TLSs in OSCC treatment.
基金supported by the National Natural Science Foundation of China,No.81271166,81371107the Natural Science Foundation of Guangdong Province in China,No.10451008901006145
文摘Very little is known about the role of melatonin in the trigeminal system, including the function of melatonin receptor 1. In the present study, adult rats were injected with formaldehyde into the right vibrissae pad to establish a model of orofacial inflammatory pain. The distribution of melatonin re- ceptor 1 and nicotinamide adenine dinucleotide phosphate diaphorase in the caudal spinal trigeminal nucleus and trigeminal ganglion was determined with immunohistochemistry and histo- chemistry. The results show that there are significant differences in melatonin receptor 1 expression and nicotinamide adenine dinucleotide phosphate diaphorase expression in the trigeminal ganglia and caudal spinal nucleus during the early stage of orofacial inflammatory pain. Our findings sug- gest that when melatonin receptor 1 expression in the caudal spinal nucleus is significantly reduced, melatonin's regulatory effect on pain is attenuated.
基金The National Natural Science Foundation of China under contract Nos 41876212,41406218 and 41676176the Polar Strategy Project from Chinese Arctic and Antarctic Administration under contract No.20120317the Opening Fund of Key Laboratory of Land Surface Process and Climate Change in Cold and Arid Regions,CAS,under contract Nos LPCC2018001 and LPCC2018005
文摘Annual observations of first-year ice(FYI) and second-year ice(SYI) near Zhongshan Station, East Antarctica,were conducted for the first time from December 2011 to December 2012. Melt ponds appeared from early December 2011. Landfast ice partly broke in late January, 2012 after a strong cyclone. Open water was refrozen to form new ice cover in mid-February, and then FYI and SYI co-existed in March with a growth rate of 0.8 cm/d for FYI and a melting rate of 2.7 cm/d for SYI. This difference was due to the oceanic heat flux and the thickness of ice,with weaker heat flux through thicker ice. From May onward, FYI and SYI showed a similar growth by 0.5 cm/d.Their maximum thickness reached 160.5 cm and 167.0 cm, respectively, in late October. Drillings showed variations of FYI thickness to be generally less than 1.0 cm, but variations were up to 33.0 cm for SYI in March,suggesting that the SYI bottom was particularly uneven. Snow distribution was strongly affected by wind and surface roughness, leading to large thickness differences in the different sites. Snow and ice thickness in Nella Fjord had a similar "east thicker, west thinner" spatial distribution. Easterly prevailing wind and local topography led to this snow pattern. Superimposed ice induced by snow cover melting in summer thickened multi-year ice,causing it to be thicker than the snow-free SYI. The estimated monthly oceanic heat flux was ~30.0 W/m2 in March–May, reducing to ~10.0 W/m2 during July–October, and increasing to ~15.0 W/m2 in November. The seasonal change and mean value of 15.6 W/m2 was similar to the findings of previous research. The results can be used to further our understanding of landfast ice for climate change study and Chinese Antarctic Expedition services.
文摘Mesenchymal stem cells(MSCs)have been widely exploited as promising candidates in clinical settings for bone repair and regeneration in view of their self-renewal capacity and multipotentiality.However,little is known about the mechanisms underlying their fate determination,which would illustrate their effectiveness in regenerative medicine.Recent evidence has shed light on a fundamental biological role of autophagy in the maintenance of the regenerative capability of MSCs and bone homeostasis.Autophagy has been implicated in provoking an immediately available cytoprotective mechanism in MSCs against stress,while dysfunction of autophagy impairs the function of MSCs,leading to imbalances of bone remodeling and a wide range of aging and degenerative bone diseases.This review aims to summarize the up-to-date knowledge about the effects of autophagy on MSC fate determination and its role as a stress adaptation response.Meanwhile,we highlight autophagy as a dynamic process and a double-edged sword to account for some discrepancies in the current research.We also discuss the contribution of autophagy to the regulation of bone cells and bone remodeling and emphasize its potential involvement in bone disease.
基金supported by the National Natural Science Foundation of China (Grant No. 41272149)National oil and gas Projects (Grant No. 2011ZX05008-002)
文摘The crude oils typically from the CambrianLower Ordovician source rocks of Tarim Basin, NW"China, such as TD2 and TZ62S, are13C-enriched with the stable carbon isotopic ratios(VPDB) approaching-28 %.In this paper, the main research viewpoints on this issue are summarized, and combined with results from organic and inorganic carbon isotope stratum curves of the outcrop at the Ya'erdang Mountain in Tarim Basin. In addition, more alternative interpretations are discussed. On one hand, the inverse fractionation features of stable carbon and hydrogen isotopes of these crude oils may imply their protogenous nature. On the other hand, the anisotropy of source rocks and contribution from older stratum source rocks need verifying as well. For the sake of the final resolution of this issue, some further study topics are recommended.