Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes(S1-3)as effective co-sensitizers for dye-sensitized solar cell(DSSC) sensitized with Ru(Ⅱ) complex(NCSU-10).In ...Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes(S1-3)as effective co-sensitizers for dye-sensitized solar cell(DSSC) sensitized with Ru(Ⅱ) complex(NCSU-10).In this new design, the electron rich carbazole unit was attached to three different electron withdrawing/anchoring species, viz. 4-amino benzoic acid, sulfanilic acid and barbituric acid. The dyes were characterized by spectral, photophysical and electrochemical analysis. Their optical and electrochemical parameters along with molecular geometries, optimized from DFT have been employed to apprehend the effect of the structures of these co-sensitizers on the photovoltaic performances. Further, S1-3 dyes were co-sensitized along with a well-known NCSU-10 dye in order to broaden the spectral response of the co-sensitized devices and hence improve the efficiency. The photovoltaic performance studies indicated that, the device fabricated using S1 dye as co-sensitizer with 0.2 mM of NCSU-10 exhibited improved PCE of 9.55% with JSC of 22.85 mA cm-2, VOC of 0.672 V and FF of 62.2%, whereas the DSSC fabricated with dye NCSU-10(0.2 mM) alone displayed PCE of 8.25% with JSC of 20.41 mA cm-2, VOC of 0.667 V and FF of 60.6%. Furthermore, electronic excitations simulated using time-dependent DFT, were in good agreement with the experimentally obtained results of the co-sensitizers, indicating that the exchange-correlation function and basis set utilized for predicting the spectra of the co-sensitizers are quite appropriate for the calculations. In conclusion, the results showed the potential of simple organic co-sensitizers in the development of efficient DSSCs.展开更多
Socialism with Chinese characteristics is a great cause without experience for reference. Under the general theme of adhering to and developing socialism with Chinese characteristics,the basic issues of socialism with...Socialism with Chinese characteristics is a great cause without experience for reference. Under the general theme of adhering to and developing socialism with Chinese characteristics,the basic issues of socialism with Chinese characteristics are specifically composed of three aspects: the ruling construction of the Communist Party of China,the construction of socialism with Chinese characteristics and the development of human society. In the process of realizing the great leap of the Chinese nation to stand up,become rich,and become strong,the Chinese Communists,mainly represented by Mao Zedong,Deng Xiaoping,Jiang Zemin,Hu Jintao and Xi Jinping,have relayed to explore the basic issues of socialism with Chinese characteristics over the past 70 years,and constantly deepen their understanding of the laws governing the construction of the ruling party,the laws of socialist construction,and the laws of the development of human society.展开更多
In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distribut...In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distributed generation(DG)based on renewable energy is critical for active distribution network operation enhancement.To comprehensively analyze the accessing impact of DG in distribution networks from various parts,this paper establishes an optimal DG location and sizing planning model based on active power losses,voltage profile,pollution emissions,and the economics of DG costs as well as meteorological conditions.Subsequently,multiobjective particle swarm optimization(MOPSO)is applied to obtain the optimal Pareto front.Besides,for the sake of avoiding the influence of the subjective setting of the weight coefficient,the decisionmethod based on amodified ideal point is applied to execute a Pareto front decision.Finally,simulation tests based on IEEE33 and IEEE69 nodes are designed.The experimental results show thatMOPSO can achieve wider and more uniformPareto front distribution.In the IEEE33 node test system,power loss,and voltage deviation decreased by 52.23%,and 38.89%,respectively,while taking the economy into account.In the IEEE69 test system,the three indexes decreased by 19.67%,and 58.96%,respectively.展开更多
Lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease(MAFLD).However,there are few reported lipotoxicity inhibitors...Lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease(MAFLD).However,there are few reported lipotoxicity inhibitors.Here,we identified a natural anti-lipotoxicity candidate,HN-001,from the marine fungus Aspergillus sp.C1.HN-001 dose-and time-dependently reversed palmitic acid(PA)-induced hepatocyte death.This protection was associated with IRE-1a-mediated XBP-1 splicing inhibition,which resulted in suppression of XBP-1s nuclear translocation and transcriptional regulation.Knockdown of XBP-1s attenuated lipotoxicity,but no additional ameliorative effect of HN-001 on lipotoxicity was observed in XBP-1s knockdown hepatocytes.Notably,the ER stress and lipotoxicity amelioration was associated with PLA2.Both HN-001 and the PLA2 inhibitor MAFP inhibited PLA2 activity,reduced lysophosphatidylcholine(LPC)level,subsequently ameliorated lipotoxicity.In contrast,overexpression of PLA2 caused exacerbation of lipotoxicity and weakened the anti-lipotoxic effects of HN-001.Additionally,HN-001 treatment suppressed the downstream pro-apoptotic JNK pathway.In vivo,chronic administration of HN-001(i.p.)in mice alleviated all manifestations of MAFLD,including hepatic steatosis,liver injury,inflammation,and fibrogenesis.These effects were correlated with PLA2/IRE-1a/XBP-1s axis and JNK signaling suppression.These data indicate that HN-001 has therapeutic potential for MAFLD because it suppresses lipotoxicity,and provide a natural structural basis for developing anti-MAFLD candidates.展开更多
The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simula...The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth.展开更多
With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is inte...With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is internationally accepted as a feasible and safe way to dispose of HLW, and underground research laboratories(URLs) play an important and multi-faceted role in the development of HLW repositories. This paper introduces the overall planning and the latest progress for China's URL. On the basis of the proposed strategy to build an area-specific URL in combination with a comprehensive evaluation of the site selection results obtained during the last 33 years, the Xinchang site in the Beishan area,located in Gansu Province of northwestern China, has been selected as the final site for China's first URL built in granite. In the process of characterizing the Xinchang URL site, a series of investigations,including borehole drilling,geological mapping, geophysical surveying,hydraulic testing and in situ stress measurements, has been conducted. The investigation results indicate that the geological,hydrogeological, engineering geological and geochemical conditions of the Xinchang site are very suitable for URL construction. Meanwhile, to validate and develop construction technologies for the Beishan URL, the Beishan exploration tunnel(BET), which is a 50-m-deep facility in the Jiujing sub-area, has been constructed and several in situ tests, such as drill-and-blast tests, characterization of the excavation damaged zone(EDZ), and long-term deformation monitoring of surrounding rocks, have been performed in the BET. The methodologies and technologies established in the BET will serve for URL construction.According to the achievements of the characterization of the URL site, a preliminary design of the URL with a maximum depth of 560 m is proposed and necessary in situ tests in the URL are planned.展开更多
Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for de...Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for determining the basic mechanical properties of rocks and revealing the mechanism of isolated pillar disasters under unidimensional stress.The shape effects of rock mechanical properties under uniaxial compression are mainly quantitatively reflected in the specific shape ratios of rocks.Therefore,it is necessary to study the detailed shape ratio effects on the mechanical properties of rectangular prism rock specimens and isolated pillars under uniaxial compressive stress.In this study,granite,marble and sandstone rectangular prism specimens with various height to width ratios(r)and width to thickness ratios(u)were prepared and tested.The study results show that r and u have a great influence on the bearing ability of rocks,and thin or high rocks have lower uniaxial compressive strength.Reducing the level of r can enhance the u effect on the strength of rocks,and increasing the level of u can enhance the r effect on the strength of rocks.The lateral strain on the thickness side of the rock specimen is larger than that on the width side,which implies that crack growth occurs easily on the thickness side.Considering r and u,a novel strength prediction model of isolated pillars was proposed based on the testing results,and the prediction model was used for the safety assessment of 179 isolated pillars in the Xianglu Mountain Tungsten Mine.展开更多
East China(23.6°–38.4°N,113.6°–122.9°E)is the largest developed region in China.Based on CO2 products retrieved from the Greenhouse Gases Observing Satellite(GOSAT),the spatial and temporal distr...East China(23.6°–38.4°N,113.6°–122.9°E)is the largest developed region in China.Based on CO2 products retrieved from the Greenhouse Gases Observing Satellite(GOSAT),the spatial and temporal distributions of CO2 mixing ratios in East China during 2014–17 are discussed,and the retrieved CO2 from AIRS(Atmospheric Infrared Sounder)and OCO-2(Orbiting Carbon Observatory-2),as well as WLG(Waliguan)background station observations,are compared with those of GOSAT.The annual CO2 retrieved from GOSAT in East China ranged from 398.96±0.24 ppm in 2014 to 407.39±0.20 ppm in 2017,with a growth rate of 2.82±0.15 ppm yr^−1,which were higher than in other regions of China.The seasonal cycle presented a maximum in spring and a minimum in summer or autumn.Higher values were mainly concentrated in the coastal areas of Zhejiang Province,and lower values were concentrated in Jiangxi and the north of Fujian Province.CO2 observed in Fujian and parts of Jiangxi increased by less than 1.0 ppm during 2014–15,but enhanced significantly by more than 5.0 ppm during 2015–16,perhaps influenced by local emissions and global impacts.We calculated year-to-year CO2 enhancements in the Yangtze River Delta region during 2014–17 that were relatively low and stable,due to the region’s carbon emissions control and reduction policies.The annual and seasonal amplitudes of CO2 retrieved from AIRS were lower than those from GOSAT in East China,probably owing to the CO2 retrieved from AIRS better reflecting the characteristics of the mid-troposphere,while GOSAT is more representative of near-surface CO2.The spatial and temporal distribution characteristics of CO2 retrieved from OCO-2 were close to those from GOSAT in East China.展开更多
Tumorous stem mustard is well known for its swollen stem from which pickled“Fuling Mustard”is made.The molecular mechanisms governing the formation of the modified swollen stems are still poorly understood.This pape...Tumorous stem mustard is well known for its swollen stem from which pickled“Fuling Mustard”is made.The molecular mechanisms governing the formation of the modified swollen stems are still poorly understood.This paper aims to identify candidate genes involved in the developmental regulation of the swollen stems.We sought to map previously published transcriptome datasets for Brassica juncea,including those derived from swollen stems at four different developmental stages and a mutant variety without swollen stems.Using pairwise comparisons of the five datasets,we identified 31368 differentially expressed genes(DEGs).A total of 55 DEGs related to plant hormone signal transduction and 259 continuously up-or downregulated transcription factors were identified during stem development using Gene Ontology(GO)analysis.Quantitative real-time PCR(qRT-PCR)results showed that the expressions of 12 important candidate DEGs were consistent with RNA-seq results.Our study provided digital gene expression profiling and a dynamic view of the swollen stem development process.Furthermore,we identified candidate genes for further studies on mechanisms of modified stem development in non-model species.展开更多
Ultra-long,single crystal,Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350℃ for 4 h.Phases,chemical composition and ...Ultra-long,single crystal,Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350℃ for 4 h.Phases,chemical composition and microcosmic feature were tested by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron mi-展开更多
To solve the problem of deformation and cracking of ballastless track slab under temperature load,a composite oxide and a series of heat-reflective coating samples were prepared.At the microscopic level,the elemental ...To solve the problem of deformation and cracking of ballastless track slab under temperature load,a composite oxide and a series of heat-reflective coating samples were prepared.At the microscopic level,the elemental composition and optical properties of the materials prepared were analyzed by Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy,and the feasibility of Ce/Si/Ti oxide as functional fillers for heat-reflective coatings of track slabs was demonstrated.At the macro level,by designing and assembling an indoor sunlight simulation test device,the surface and internal temperatures of the coated and uncoated concrete specimens were analyzed and studied,and the macroscopic cooling effect of the coatings was evaluated.Also,to study the engineering application effect of the track slab thermal insulation reflective coating,COMSOL was used to build a 3D calculation model of the heat transfer deformation of the ballastless track slab structure.The research results showed that:Ce/Si/Ti oxide has strong reflectivity and can reflect 95%of infrared light;it has good ultraviolet(UV)shielding ability and can absorb more than 65%of the UV light.The TiO2 coating can reduce the temperature of the concrete surface by 6–11℃and that of the inside of the concrete by 10–14℃;the cooling effect decreases evenly with the increase of air temperature.The Ce/Si/Ti oxide coating can reduce the surface temperature of the concrete by 16℃and that of the inside of the concrete by 15℃.In addition,the cooling effect is basically not affected by the air temperature,and it changes non-linearly with the increase of the Ce/Si/Ti oxide content.Numerical calculation shows that the heat reflective coating can reduce the surface temperature and internal temperature difference of the track slab by 11.54–21.31℃,and the vertical displacement of the track slab can be reduced by about 35%–70%.Considering the cooling effect,the adhesion strength,and the engineering application effect of the coating,the optimal doping amount of Ce/Si/Ti oxide is 40%,and that coating is the most suitable for use as a ballastless track heat reflective coating.展开更多
本研究旨在分析SpO_(2)/HCT比值作为高原习服性评估指标对高原习服与适应的预测价值.收集了西藏自治区某医院2347名接受常规体检的患者体检报告,并由高原病研究专家根据患者体检报告和问诊结果,将患者分为高原习服性组和高原不习服组.采...本研究旨在分析SpO_(2)/HCT比值作为高原习服性评估指标对高原习服与适应的预测价值.收集了西藏自治区某医院2347名接受常规体检的患者体检报告,并由高原病研究专家根据患者体检报告和问诊结果,将患者分为高原习服性组和高原不习服组.采用SpO_(2)/HCT指标作为高原习服性评估指标,并对两组进行比较.同时,分析高原习服性评估指标与慢性高原病(chronic mountain sickness,CMS)之间的相关性.使用受试者工作特征(receiver operating characteristic,ROC)曲线下面积(area under the curve,AUC)来评估高原习服性评估指标对高原习服良好与不良人群的诊断效能.通过SpO_(2)/HCT指标与世居者生理生化指标的关联,证明了SpO_(2)/HCT比值评估的准确性.本研究确认,SpO_(2)/HCT指标(altitude acclimatization/adaptation index,AAI)能够有效评估个体在高原的习服和适应水平.AAI=1.7228被确定为高原习服和适应的临界值,小于1.7228表示习服和适应不良,而大于等于1.7228表示习服和适应良好.AAI适用于高海拔移居者和世居者的高原习服或适应程度评估.展开更多
Epitranscriptomics focuses on the RNA-modification-mediated post-transcriptional regulation of gene expression.The past decade has witnessed tremendous progress in our understanding of the landscapes and biological fu...Epitranscriptomics focuses on the RNA-modification-mediated post-transcriptional regulation of gene expression.The past decade has witnessed tremendous progress in our understanding of the landscapes and biological functions of RNA modifications,as prompted by the emergence of potent analytical approaches.The hematopoietic system provides a lifelong supply of blood cells,and gene expression is tightly controlled during the differentiation of hematopoietic stem cells(HSCs).The dysregulation of gene expression during hematopoiesis may lead to severe disorders,including acute myeloid leukemia(AML).Emerging evidence supports the involvement of the mRNA modification system in normal hematopoiesis and AML pathogenesis,which has led to the development of small-molecule inhibitors that target N6-methyladenosine(m^(6)A)modification machinery as treatments.Here,we summarize the latest findings and our most up-to-date information on the roles of m^(6)A and N7-methylguanine in both physiological and pathological conditions in the hematopoietic system.Furthermore,we will discuss the therapeutic potential and limitations of cancer treatments targeting m^(6)A.展开更多
As the most common internal modification of mRNA,Ne-methyladenosine(m^(6)A)and its regulators modulate gene expression and play critical roles in various biological and patholog-ical processes including tumorigenesis....As the most common internal modification of mRNA,Ne-methyladenosine(m^(6)A)and its regulators modulate gene expression and play critical roles in various biological and patholog-ical processes including tumorigenesis.It was reported previously that m^(6)A methyltransferase(writer),methyltransferase-like 3(METTL3)adds m^(6)A in primary microRNAs(pri-miRNAs)and fa-cilitates its processing into precursor miRNAs(pre-miRNAs).However,it is unknown whether m^(6)A modification also plays a role in the maturation process of pre-miRNAs and(if so)whether such a function contributes to tumorigenesis.Here,we found that YTHDF2 is aberrantly overexpressed in acute myeloid leukemia(AML)patients,especially in relapsed patients,and plays an onco-genic role in AML.Moreover,YTHDF2 promotes expression of miR-126-3p(also known as miR-126,as it is the main product of precursor miR-126(pre-miR-126)),a miRNA that was reported as an oncomiRNA in AML,through facilitating the processing of pre-miR-126 into mature miR-126.Mechanistically,YTHDF2 recognizes m^(6)A modification in pre-miR-126 and recruits AGO2,a regulator of pre-miRNA processing,to promote the maturation of pre-miR-126.YTHDF2 posi-tively and negatively correlates with miR-126 and miR-126's downstream target genes,respec-tively,in AML patients,and forced expression of miR-126 could largely rescue YTHDF2/Ythdf2 depletion-mediated suppression on AML cell growth/proliferation and leukemogenesis,indi-cating that miR-126 is a functionally important target of YTHDF2 in AML.Overall,our studies not only reveal a previously unappreciated YTHDF2/miR-126 axis in AML and highlight the ther-apeutic potential of targeting this axis for AML treatment,but also suggest that m^(6)A plays a role in pre-miRNA processing that contributes to tumorigenesis.展开更多
As a kind of renewable and high oxygen content fuel,polyoxymethylene dimethyl ether(PODE)can be added in diesel to realize energy saving and emissions reduction.To evaluate the combustion and emission characteristics ...As a kind of renewable and high oxygen content fuel,polyoxymethylene dimethyl ether(PODE)can be added in diesel to realize energy saving and emissions reduction.To evaluate the combustion and emission characteristics of a diesel engine fueled with diesel and diesel/PODE mixtures,exhaust gas recirculation(EGR)and main-pilot injection strategies with various injection timings were applied.PODE was blended with diesel by volume to form mixtures which were marked as D100(pure diesel),D90P10(90%diesel+10%PODE),and D80P20(80%diesel+20%PODE).The results showed that the ignition delay(ID)and combustion duration(CD)of D80P20 were the shortest because of the highest cetane number(CN)and high oxygen content of PODE,indicating more concentrated heat release.At low and medium loads,D80P20 achieved the highest peak heat release ratio(PHRR)and peak combustion temperature(PCT)among the three fuels,and it was 14.3%and 3.6%higher than those of D100.PODE blending with diesel can significantly reduce particulate matter(PM)and D80P20 has the lowest PM emissions at all loads.Compared with D100,both PM and nitrogen oxide(NO_(x))emissions of PODE blends decreased simultaneously with 20%EGR at all loads.With the increase of pilot-main interval,the ID and CD of all test fuels increased,while the NO_(x)and PM emissions decreased.The conclusions of the present research provide a state of the application in light-duty engines fueled with diesel/PODE blends in future work.展开更多
Single-cell joint analysis of methylome and transcriptome reveals how the methylation regulates the transcriptional activity.However,traditional bench-top protocols for single-cell DNA methylation and RNA transcriptio...Single-cell joint analysis of methylome and transcriptome reveals how the methylation regulates the transcriptional activity.However,traditional bench-top protocols for single-cell DNA methylation and RNA transcription co-detection are laborintensive,cost-ineffective and contaminant-prone.Herein,we establish the DMF-sc MT-seq,a highly-efficient and cost-effective method to simultaneously analyze single-cell DNA methylation and transcriptional activity based on digital microfluidics.DMFsc MT-seq automates the workflow of single-cell isolation,cellular hypotonic lysis,nucleic acid separation and methylome/transcriptome library construction in a contactless and addressable way.The system ensures high accuracy(R>0.85),high gene detection ability(14,697 genes per cell at 4 million sequencing depth),and high CpG coverage(677,198 CpG sites per cell at 1million sequencing depth).By using DMF-sc MT-seq,the relationship of DNA methylation and RNA transcription under different genomic contexts is resolved.We further apply DMF-sc MT-seq to study the dynamics of transcription regulation with methylation-inhibiting anti-tumor Decitabine,and identify the methylated promoter/gene body driven genes in response to Decitabine treatment.DMF-sc MT-seq facilitates the construction of the correlation of DNA methylation and transcriptional activity at the single-cell level in a flexible,sensitive and accurate way,which is anticipated to be a powerful tool in studying single-cell biological systems.展开更多
Constructing an accurate interatomic potential and overcoming the exponential growth of structural equilibration time are challenges for atomistic investigations of the composition-dependent structure and dynamics dur...Constructing an accurate interatomic potential and overcoming the exponential growth of structural equilibration time are challenges for atomistic investigations of the composition-dependent structure and dynamics during the vitrification process of deeply supercooled multicomponent metallic liquids.In this work,we describe a state-of-the-art strategy to address these challenges simultaneously.In the case of the representative Zr–Cu–Al system,in combination with a general algorithm for effectively and accurately generating the neural network potentials(NNPs)of multicomponent metallic glasses,we propose a highly efficient atom-swapping hybrid Monte Carlo(SHMC)algorithm for accelerating the thermodynamic equilibration of deeply supercooled liquids.Extensive calculations demonstrate that the newly developed NNP faithfully reproduces the phase stabilities and structural characteristics obtained from ab initio calculations and experiments.In the combined NNP-SHMC algorithm,the structure equilibration time at deeply supercooled temperatures is accelerated by at least five orders of magnitude,and the quenched glassy samples exhibit comparable stability to those prepared in the laboratory.Our results pave the way for next-generation studies of the vitrification process and,thereby,the composition-dependent glass-forming ability and physical properties of multicomponent metallic glasses.展开更多
基金Department of Textile Engineering, Chemistry and Science at North Carolina State University for the financial support
文摘Herein, we report the design and synthesis of three new D-A type metal-free carbazole based dyes(S1-3)as effective co-sensitizers for dye-sensitized solar cell(DSSC) sensitized with Ru(Ⅱ) complex(NCSU-10).In this new design, the electron rich carbazole unit was attached to three different electron withdrawing/anchoring species, viz. 4-amino benzoic acid, sulfanilic acid and barbituric acid. The dyes were characterized by spectral, photophysical and electrochemical analysis. Their optical and electrochemical parameters along with molecular geometries, optimized from DFT have been employed to apprehend the effect of the structures of these co-sensitizers on the photovoltaic performances. Further, S1-3 dyes were co-sensitized along with a well-known NCSU-10 dye in order to broaden the spectral response of the co-sensitized devices and hence improve the efficiency. The photovoltaic performance studies indicated that, the device fabricated using S1 dye as co-sensitizer with 0.2 mM of NCSU-10 exhibited improved PCE of 9.55% with JSC of 22.85 mA cm-2, VOC of 0.672 V and FF of 62.2%, whereas the DSSC fabricated with dye NCSU-10(0.2 mM) alone displayed PCE of 8.25% with JSC of 20.41 mA cm-2, VOC of 0.667 V and FF of 60.6%. Furthermore, electronic excitations simulated using time-dependent DFT, were in good agreement with the experimentally obtained results of the co-sensitizers, indicating that the exchange-correlation function and basis set utilized for predicting the spectra of the co-sensitizers are quite appropriate for the calculations. In conclusion, the results showed the potential of simple organic co-sensitizers in the development of efficient DSSCs.
文摘Socialism with Chinese characteristics is a great cause without experience for reference. Under the general theme of adhering to and developing socialism with Chinese characteristics,the basic issues of socialism with Chinese characteristics are specifically composed of three aspects: the ruling construction of the Communist Party of China,the construction of socialism with Chinese characteristics and the development of human society. In the process of realizing the great leap of the Chinese nation to stand up,become rich,and become strong,the Chinese Communists,mainly represented by Mao Zedong,Deng Xiaoping,Jiang Zemin,Hu Jintao and Xi Jinping,have relayed to explore the basic issues of socialism with Chinese characteristics over the past 70 years,and constantly deepen their understanding of the laws governing the construction of the ruling party,the laws of socialist construction,and the laws of the development of human society.
基金The authors gratefully acknowledge the support of the Enhancement Strategy of Multi-Type Energy Integration of Active Distribution Network(YNKJXM20220113).
文摘In the framework of vigorous promotion of low-carbon power system growth as well as economic globalization,multi-resource penetration in active distribution networks has been advancing fiercely.In particular,distributed generation(DG)based on renewable energy is critical for active distribution network operation enhancement.To comprehensively analyze the accessing impact of DG in distribution networks from various parts,this paper establishes an optimal DG location and sizing planning model based on active power losses,voltage profile,pollution emissions,and the economics of DG costs as well as meteorological conditions.Subsequently,multiobjective particle swarm optimization(MOPSO)is applied to obtain the optimal Pareto front.Besides,for the sake of avoiding the influence of the subjective setting of the weight coefficient,the decisionmethod based on amodified ideal point is applied to execute a Pareto front decision.Finally,simulation tests based on IEEE33 and IEEE69 nodes are designed.The experimental results show thatMOPSO can achieve wider and more uniformPareto front distribution.In the IEEE33 node test system,power loss,and voltage deviation decreased by 52.23%,and 38.89%,respectively,while taking the economy into account.In the IEEE69 test system,the three indexes decreased by 19.67%,and 58.96%,respectively.
基金This study was supported by National Natural Science Foundation of China(82260674 to Yong Rao,82160653 to Ling Huang)Fundamental Research Funds for Hainan University(KYQD(ZR)-21114 to Yong Rao,KYQD(ZR)-21089 to Ling Huang,China)+2 种基金Hainan Provincial Natural Science Foundation of China(822MS054 to Yong Rao)Natural Science Foundation of Guangdong Province(2021A1515010488 to Yong Rao,China)Central Public-interest Scientific Institution Basal Research Fund for CATAS-ITBB(1630052022016,1630052019011,China).
文摘Lipotoxicity is a pivotal factor that initiates and exacerbates liver injury and is involved in the development of metabolic-associated fatty liver disease(MAFLD).However,there are few reported lipotoxicity inhibitors.Here,we identified a natural anti-lipotoxicity candidate,HN-001,from the marine fungus Aspergillus sp.C1.HN-001 dose-and time-dependently reversed palmitic acid(PA)-induced hepatocyte death.This protection was associated with IRE-1a-mediated XBP-1 splicing inhibition,which resulted in suppression of XBP-1s nuclear translocation and transcriptional regulation.Knockdown of XBP-1s attenuated lipotoxicity,but no additional ameliorative effect of HN-001 on lipotoxicity was observed in XBP-1s knockdown hepatocytes.Notably,the ER stress and lipotoxicity amelioration was associated with PLA2.Both HN-001 and the PLA2 inhibitor MAFP inhibited PLA2 activity,reduced lysophosphatidylcholine(LPC)level,subsequently ameliorated lipotoxicity.In contrast,overexpression of PLA2 caused exacerbation of lipotoxicity and weakened the anti-lipotoxic effects of HN-001.Additionally,HN-001 treatment suppressed the downstream pro-apoptotic JNK pathway.In vivo,chronic administration of HN-001(i.p.)in mice alleviated all manifestations of MAFLD,including hepatic steatosis,liver injury,inflammation,and fibrogenesis.These effects were correlated with PLA2/IRE-1a/XBP-1s axis and JNK signaling suppression.These data indicate that HN-001 has therapeutic potential for MAFLD because it suppresses lipotoxicity,and provide a natural structural basis for developing anti-MAFLD candidates.
基金sponsored by the National Natural Science Foundation of China (Grant No. 52101201)supported by the National Natural Science Foundation of China (Grant No.T2325004)+2 种基金sponsored by the National Natural Science Foundation of China(Grant No. 51801046)the Natural Science Foundation of Chongqing,China (Grant No. cstc2021jcyj-msxm X0369)the Science Fund for Scientific and Technological Innovation Team of Shaanxi Province (Grant No. 2021TD-14)。
文摘The fast dynamic properties of the surface of metallic glasses(MGs) play a critical role in determining their potential applications. However, due to the significant difference in thermal history between atomic simulation models and laboratory-made samples, the atomic-scale behaviors of the fast surface dynamics of MGs in experiments remain uncertain. Herein, we prepared model MG films with notable variations in thermal stability using a recently developed efficient annealing protocol, and investigated their atomic-scale dynamics systematically. We found that the dynamics of surface atoms remain invariant, whereas the difference in dynamical heterogeneity between surface and interior regions increases with the improvement of thermal stability. This can be associated with the more pronounced correlation between atomic activation energy spectra and depth from the surface in samples with higher thermal stability. In addition, dynamic anisotropy appears for surface atoms, and their transverse dynamics are faster than normal components, which can also be interpreted by activation energy spectra. Our results reveal the presence of strong liquid-like atomic dynamics confined to the surface of laboratory-made MGs, illuminating the underlying mechanisms for surface engineering design, such as cold joining by ultrasonic vibrations and superlattice growth.
基金support from the China Atomic Energy Authority (CAEA) for China's URL Development Program and the Geological Disposal ProgramThe International Atomic Energy Agency is specially thanked for its support for China's geological disposal program through its Technical Cooperation Projects
文摘With the rapid development of nuclear power in China, the disposal of high-level radioactive waste(HLW) has become an important issue for nuclear safety and environmental protection. Deep geological disposal is internationally accepted as a feasible and safe way to dispose of HLW, and underground research laboratories(URLs) play an important and multi-faceted role in the development of HLW repositories. This paper introduces the overall planning and the latest progress for China's URL. On the basis of the proposed strategy to build an area-specific URL in combination with a comprehensive evaluation of the site selection results obtained during the last 33 years, the Xinchang site in the Beishan area,located in Gansu Province of northwestern China, has been selected as the final site for China's first URL built in granite. In the process of characterizing the Xinchang URL site, a series of investigations,including borehole drilling,geological mapping, geophysical surveying,hydraulic testing and in situ stress measurements, has been conducted. The investigation results indicate that the geological,hydrogeological, engineering geological and geochemical conditions of the Xinchang site are very suitable for URL construction. Meanwhile, to validate and develop construction technologies for the Beishan URL, the Beishan exploration tunnel(BET), which is a 50-m-deep facility in the Jiujing sub-area, has been constructed and several in situ tests, such as drill-and-blast tests, characterization of the excavation damaged zone(EDZ), and long-term deformation monitoring of surrounding rocks, have been performed in the BET. The methodologies and technologies established in the BET will serve for URL construction.According to the achievements of the characterization of the URL site, a preliminary design of the URL with a maximum depth of 560 m is proposed and necessary in situ tests in the URL are planned.
基金funded by the National Natural Science Foundation of China(Nos.51774326,42177164,41807259,and41702350)Hunan Young Talent(No.2021RC3007)+2 种基金the open fund of Mining Disaster Prevention and Control Ministry Key Laboratory at Shandong University of Science and Technology(No.MDPC201917)the Fundamental Research Funds for the Central Universities of Central South University(No.2019zzts668)the Innovation-Driven Project of Central South University(No.2020CX040)。
文摘Isolated pillars in underground mines are subjected to uniaxial stress,and the load bearing cross-section of pillars is commonly rectangularly shaped.In addition,the uniaxial compression test(UCT)is widely used for determining the basic mechanical properties of rocks and revealing the mechanism of isolated pillar disasters under unidimensional stress.The shape effects of rock mechanical properties under uniaxial compression are mainly quantitatively reflected in the specific shape ratios of rocks.Therefore,it is necessary to study the detailed shape ratio effects on the mechanical properties of rectangular prism rock specimens and isolated pillars under uniaxial compressive stress.In this study,granite,marble and sandstone rectangular prism specimens with various height to width ratios(r)and width to thickness ratios(u)were prepared and tested.The study results show that r and u have a great influence on the bearing ability of rocks,and thin or high rocks have lower uniaxial compressive strength.Reducing the level of r can enhance the u effect on the strength of rocks,and increasing the level of u can enhance the r effect on the strength of rocks.The lateral strain on the thickness side of the rock specimen is larger than that on the width side,which implies that crack growth occurs easily on the thickness side.Considering r and u,a novel strength prediction model of isolated pillars was proposed based on the testing results,and the prediction model was used for the safety assessment of 179 isolated pillars in the Xianglu Mountain Tungsten Mine.
基金The authors thank the staff of WLG station in Qinghai Province for their data sampling and maintenance of the observation system.We are also grateful to NASA for providing the CO2 products retrieved from AIRS,OCO-2 and JAXA for providing the CO2 product retrieved from GOSAT.This research was supported by the China Meteorological Administration Climate Change Special Project(No.CCSF202035)the Jiangxi Meteorological Science and Technology Project(201805,201905).
文摘East China(23.6°–38.4°N,113.6°–122.9°E)is the largest developed region in China.Based on CO2 products retrieved from the Greenhouse Gases Observing Satellite(GOSAT),the spatial and temporal distributions of CO2 mixing ratios in East China during 2014–17 are discussed,and the retrieved CO2 from AIRS(Atmospheric Infrared Sounder)and OCO-2(Orbiting Carbon Observatory-2),as well as WLG(Waliguan)background station observations,are compared with those of GOSAT.The annual CO2 retrieved from GOSAT in East China ranged from 398.96±0.24 ppm in 2014 to 407.39±0.20 ppm in 2017,with a growth rate of 2.82±0.15 ppm yr^−1,which were higher than in other regions of China.The seasonal cycle presented a maximum in spring and a minimum in summer or autumn.Higher values were mainly concentrated in the coastal areas of Zhejiang Province,and lower values were concentrated in Jiangxi and the north of Fujian Province.CO2 observed in Fujian and parts of Jiangxi increased by less than 1.0 ppm during 2014–15,but enhanced significantly by more than 5.0 ppm during 2015–16,perhaps influenced by local emissions and global impacts.We calculated year-to-year CO2 enhancements in the Yangtze River Delta region during 2014–17 that were relatively low and stable,due to the region’s carbon emissions control and reduction policies.The annual and seasonal amplitudes of CO2 retrieved from AIRS were lower than those from GOSAT in East China,probably owing to the CO2 retrieved from AIRS better reflecting the characteristics of the mid-troposphere,while GOSAT is more representative of near-surface CO2.The spatial and temporal distribution characteristics of CO2 retrieved from OCO-2 were close to those from GOSAT in East China.
基金supported by the National Natural Science Foundation of China(Grant No.31701928)the Chongqing Natural Science Foundation(Grant No.cstc2017jcyjAX0226)+1 种基金the Science and Technology Research Program of Chongqing Municipal Education Commission(Grant No.KJ1712305)research grants of Yangtze Normal University(Grant Nos.2016XJQN07,2016KYQD19).
文摘Tumorous stem mustard is well known for its swollen stem from which pickled“Fuling Mustard”is made.The molecular mechanisms governing the formation of the modified swollen stems are still poorly understood.This paper aims to identify candidate genes involved in the developmental regulation of the swollen stems.We sought to map previously published transcriptome datasets for Brassica juncea,including those derived from swollen stems at four different developmental stages and a mutant variety without swollen stems.Using pairwise comparisons of the five datasets,we identified 31368 differentially expressed genes(DEGs).A total of 55 DEGs related to plant hormone signal transduction and 259 continuously up-or downregulated transcription factors were identified during stem development using Gene Ontology(GO)analysis.Quantitative real-time PCR(qRT-PCR)results showed that the expressions of 12 important candidate DEGs were consistent with RNA-seq results.Our study provided digital gene expression profiling and a dynamic view of the swollen stem development process.Furthermore,we identified candidate genes for further studies on mechanisms of modified stem development in non-model species.
文摘Ultra-long,single crystal,Eu-doped α-Si3N4 nanowires were prepared by a simple approach involving nitriding Eu-doped cryomilled nanocrystalline Si powder in NH3 flow at 1350℃ for 4 h.Phases,chemical composition and microcosmic feature were tested by X-ray diffraction(XRD),field emission scanning electron microscopy(FESEM),transmission electron mi-
基金supported by the National Natural Science Foundation of China(No.51978588)。
文摘To solve the problem of deformation and cracking of ballastless track slab under temperature load,a composite oxide and a series of heat-reflective coating samples were prepared.At the microscopic level,the elemental composition and optical properties of the materials prepared were analyzed by Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy,and the feasibility of Ce/Si/Ti oxide as functional fillers for heat-reflective coatings of track slabs was demonstrated.At the macro level,by designing and assembling an indoor sunlight simulation test device,the surface and internal temperatures of the coated and uncoated concrete specimens were analyzed and studied,and the macroscopic cooling effect of the coatings was evaluated.Also,to study the engineering application effect of the track slab thermal insulation reflective coating,COMSOL was used to build a 3D calculation model of the heat transfer deformation of the ballastless track slab structure.The research results showed that:Ce/Si/Ti oxide has strong reflectivity and can reflect 95%of infrared light;it has good ultraviolet(UV)shielding ability and can absorb more than 65%of the UV light.The TiO2 coating can reduce the temperature of the concrete surface by 6–11℃and that of the inside of the concrete by 10–14℃;the cooling effect decreases evenly with the increase of air temperature.The Ce/Si/Ti oxide coating can reduce the surface temperature of the concrete by 16℃and that of the inside of the concrete by 15℃.In addition,the cooling effect is basically not affected by the air temperature,and it changes non-linearly with the increase of the Ce/Si/Ti oxide content.Numerical calculation shows that the heat reflective coating can reduce the surface temperature and internal temperature difference of the track slab by 11.54–21.31℃,and the vertical displacement of the track slab can be reduced by about 35%–70%.Considering the cooling effect,the adhesion strength,and the engineering application effect of the coating,the optimal doping amount of Ce/Si/Ti oxide is 40%,and that coating is the most suitable for use as a ballastless track heat reflective coating.
文摘本研究旨在分析SpO_(2)/HCT比值作为高原习服性评估指标对高原习服与适应的预测价值.收集了西藏自治区某医院2347名接受常规体检的患者体检报告,并由高原病研究专家根据患者体检报告和问诊结果,将患者分为高原习服性组和高原不习服组.采用SpO_(2)/HCT指标作为高原习服性评估指标,并对两组进行比较.同时,分析高原习服性评估指标与慢性高原病(chronic mountain sickness,CMS)之间的相关性.使用受试者工作特征(receiver operating characteristic,ROC)曲线下面积(area under the curve,AUC)来评估高原习服性评估指标对高原习服良好与不良人群的诊断效能.通过SpO_(2)/HCT指标与世居者生理生化指标的关联,证明了SpO_(2)/HCT比值评估的准确性.本研究确认,SpO_(2)/HCT指标(altitude acclimatization/adaptation index,AAI)能够有效评估个体在高原的习服和适应水平.AAI=1.7228被确定为高原习服和适应的临界值,小于1.7228表示习服和适应不良,而大于等于1.7228表示习服和适应良好.AAI适用于高海拔移居者和世居者的高原习服或适应程度评估.
基金supported by grants from the National Key Research and Development Program of China(Nos.2019YFA0111700,2019YFA0802603,2019YFA0801800,and 2021YFA0805703)the National Natural Science Foundation of China(Nos.81970154 and 82270192)CAMS Innovation Fund for Medical Sciences(No.2022-I2M-2-001)
文摘Epitranscriptomics focuses on the RNA-modification-mediated post-transcriptional regulation of gene expression.The past decade has witnessed tremendous progress in our understanding of the landscapes and biological functions of RNA modifications,as prompted by the emergence of potent analytical approaches.The hematopoietic system provides a lifelong supply of blood cells,and gene expression is tightly controlled during the differentiation of hematopoietic stem cells(HSCs).The dysregulation of gene expression during hematopoiesis may lead to severe disorders,including acute myeloid leukemia(AML).Emerging evidence supports the involvement of the mRNA modification system in normal hematopoiesis and AML pathogenesis,which has led to the development of small-molecule inhibitors that target N6-methyladenosine(m^(6)A)modification machinery as treatments.Here,we summarize the latest findings and our most up-to-date information on the roles of m^(6)A and N7-methylguanine in both physiological and pathological conditions in the hematopoietic system.Furthermore,we will discuss the therapeutic potential and limitations of cancer treatments targeting m^(6)A.
基金supported in part by the U.S.National Institutes of Health(NIH)grants R01 CA243386(J.C.),R01 CA271497,R01 CA214965(J.C.),R01 CA236399(J.C.),R01 DK124116(J.C)The Simms/Mann Family Foundation(J.C.).J.C.is a Leukemia&Lymphoma Society(LLS)Scholar and is supported by the LLS 2022 Scholar CDP Achievement Award.
文摘As the most common internal modification of mRNA,Ne-methyladenosine(m^(6)A)and its regulators modulate gene expression and play critical roles in various biological and patholog-ical processes including tumorigenesis.It was reported previously that m^(6)A methyltransferase(writer),methyltransferase-like 3(METTL3)adds m^(6)A in primary microRNAs(pri-miRNAs)and fa-cilitates its processing into precursor miRNAs(pre-miRNAs).However,it is unknown whether m^(6)A modification also plays a role in the maturation process of pre-miRNAs and(if so)whether such a function contributes to tumorigenesis.Here,we found that YTHDF2 is aberrantly overexpressed in acute myeloid leukemia(AML)patients,especially in relapsed patients,and plays an onco-genic role in AML.Moreover,YTHDF2 promotes expression of miR-126-3p(also known as miR-126,as it is the main product of precursor miR-126(pre-miR-126)),a miRNA that was reported as an oncomiRNA in AML,through facilitating the processing of pre-miR-126 into mature miR-126.Mechanistically,YTHDF2 recognizes m^(6)A modification in pre-miR-126 and recruits AGO2,a regulator of pre-miRNA processing,to promote the maturation of pre-miR-126.YTHDF2 posi-tively and negatively correlates with miR-126 and miR-126's downstream target genes,respec-tively,in AML patients,and forced expression of miR-126 could largely rescue YTHDF2/Ythdf2 depletion-mediated suppression on AML cell growth/proliferation and leukemogenesis,indi-cating that miR-126 is a functionally important target of YTHDF2 in AML.Overall,our studies not only reveal a previously unappreciated YTHDF2/miR-126 axis in AML and highlight the ther-apeutic potential of targeting this axis for AML treatment,but also suggest that m^(6)A plays a role in pre-miRNA processing that contributes to tumorigenesis.
基金supported by the Innovation Capability Support Program of Shaanxi(2021TD-28,2022KXJ-144)the Key Research and Development Program of Shaanxi(2019ZDLGY15-07)+1 种基金the Youth Innovation Team of Shaanxi Universitiesthe Special Fund for Basic Scientific Research of Central Colleges,Chang'an University(300102222401,300102222510)。
文摘As a kind of renewable and high oxygen content fuel,polyoxymethylene dimethyl ether(PODE)can be added in diesel to realize energy saving and emissions reduction.To evaluate the combustion and emission characteristics of a diesel engine fueled with diesel and diesel/PODE mixtures,exhaust gas recirculation(EGR)and main-pilot injection strategies with various injection timings were applied.PODE was blended with diesel by volume to form mixtures which were marked as D100(pure diesel),D90P10(90%diesel+10%PODE),and D80P20(80%diesel+20%PODE).The results showed that the ignition delay(ID)and combustion duration(CD)of D80P20 were the shortest because of the highest cetane number(CN)and high oxygen content of PODE,indicating more concentrated heat release.At low and medium loads,D80P20 achieved the highest peak heat release ratio(PHRR)and peak combustion temperature(PCT)among the three fuels,and it was 14.3%and 3.6%higher than those of D100.PODE blending with diesel can significantly reduce particulate matter(PM)and D80P20 has the lowest PM emissions at all loads.Compared with D100,both PM and nitrogen oxide(NO_(x))emissions of PODE blends decreased simultaneously with 20%EGR at all loads.With the increase of pilot-main interval,the ID and CD of all test fuels increased,while the NO_(x)and PM emissions decreased.The conclusions of the present research provide a state of the application in light-duty engines fueled with diesel/PODE blends in future work.
基金supported by the National Natural Science Foundation of China(21927806,22204132,22104080)the National Key R&D Program of China(2019YFA0905800)+1 种基金the Innovative Research Team of High-Level Local Universities in Shanghai,and the Fundamental Research Funds for the Central Universities(2072021000,20720210005)the Natural Science Foundation of Fujian Province(2022J011360)。
文摘Single-cell joint analysis of methylome and transcriptome reveals how the methylation regulates the transcriptional activity.However,traditional bench-top protocols for single-cell DNA methylation and RNA transcription co-detection are laborintensive,cost-ineffective and contaminant-prone.Herein,we establish the DMF-sc MT-seq,a highly-efficient and cost-effective method to simultaneously analyze single-cell DNA methylation and transcriptional activity based on digital microfluidics.DMFsc MT-seq automates the workflow of single-cell isolation,cellular hypotonic lysis,nucleic acid separation and methylome/transcriptome library construction in a contactless and addressable way.The system ensures high accuracy(R>0.85),high gene detection ability(14,697 genes per cell at 4 million sequencing depth),and high CpG coverage(677,198 CpG sites per cell at 1million sequencing depth).By using DMF-sc MT-seq,the relationship of DNA methylation and RNA transcription under different genomic contexts is resolved.We further apply DMF-sc MT-seq to study the dynamics of transcription regulation with methylation-inhibiting anti-tumor Decitabine,and identify the methylated promoter/gene body driven genes in response to Decitabine treatment.DMF-sc MT-seq facilitates the construction of the correlation of DNA methylation and transcriptional activity at the single-cell level in a flexible,sensitive and accurate way,which is anticipated to be a powerful tool in studying single-cell biological systems.
基金supported by the National Natural Science Foundation of China(T2325004 and 52161160330)the National Key R&D Program of China(2017YFA0303400)+1 种基金the Young Scientists Fund of the National Natural Science Foundation of China(51801046)the fund from the Foundation of National Key Laboratory of Computational Physics(6142A05220402)。
文摘Constructing an accurate interatomic potential and overcoming the exponential growth of structural equilibration time are challenges for atomistic investigations of the composition-dependent structure and dynamics during the vitrification process of deeply supercooled multicomponent metallic liquids.In this work,we describe a state-of-the-art strategy to address these challenges simultaneously.In the case of the representative Zr–Cu–Al system,in combination with a general algorithm for effectively and accurately generating the neural network potentials(NNPs)of multicomponent metallic glasses,we propose a highly efficient atom-swapping hybrid Monte Carlo(SHMC)algorithm for accelerating the thermodynamic equilibration of deeply supercooled liquids.Extensive calculations demonstrate that the newly developed NNP faithfully reproduces the phase stabilities and structural characteristics obtained from ab initio calculations and experiments.In the combined NNP-SHMC algorithm,the structure equilibration time at deeply supercooled temperatures is accelerated by at least five orders of magnitude,and the quenched glassy samples exhibit comparable stability to those prepared in the laboratory.Our results pave the way for next-generation studies of the vitrification process and,thereby,the composition-dependent glass-forming ability and physical properties of multicomponent metallic glasses.