Based on questionnaire data from Niutouzhen Village Units 1-7 in Shuangwangcheng Economic Zone,Shouguang City,Shandong Province,this study employs a binary logistic regression model to explore the factors influencing ...Based on questionnaire data from Niutouzhen Village Units 1-7 in Shuangwangcheng Economic Zone,Shouguang City,Shandong Province,this study employs a binary logistic regression model to explore the factors influencing farmers'willingness to transfer farmland,and uses SPSS 27.0 software to perform regression analysis on the data.The results indicate that farmers'educational level,age of the household head,and contracted land area have a positive influence on farmers'willingness to transfer farmland at the 0.05 significance level,while annual household income has a positive influence at the 0.10 significance level.Furthermore,based on the regression analysis results,measures are proposed,including establishing and improving the rural land transfer compensation mechanism,enhancing publicity for land transfer,refining land transfer laws and regulations,optimizing the rural social security system,and actively expanding non-agricultural employment channels.These measures are intended to provide references for promoting farmland transfer work in Shouguang City.展开更多
The escalating production of industrial solid waste,combined with the dwindling availability of natural resources,has intensified the focus on waste recycling.However,the heterogeneity and complexity of waste pose sig...The escalating production of industrial solid waste,combined with the dwindling availability of natural resources,has intensified the focus on waste recycling.However,the heterogeneity and complexity of waste pose significant challenges to determining process parameters.In this study,burnt coal cinder(BCC),granite powder(GP),and high-calcium fly ash(Class-C FA)were used as raw materials,and the response surface methodology(RSM)and single-factor experiments were applied to optimize the process parameters for geopolymer preparation.The optimized precursor powder composition was determined to be a mass ratio of 1.6:0.9:7.3 for BCC,GP,and Class-C FA.The NaOH-precursor powder ratio and liquid-solid ratio were adjusted to 0.084 and 0.222,respectively.The curing condition was set at 80℃ for 24 h.The resulting 28 d-aged multi-solid wastes-based geopolymer exhibited a high compressive strength of61.34 MPa.The microstructure,mineral phase,and atomic bonding of geopolymers were investigated using X-ray diffraction(XRD),thermal analysis(TA),Fourier transform infrared spectroscopy(FTIR),and scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS).Findings indicate that the compressive strength of geopolymer is most significantly influenced by the Class-C FA,followed by BCC.Furthermore,a minor addition of GP can optimize the structural density of the geopolymer.The Ca present in the Class-C FA participates in the geopolymerization,forming a hybrid N-(C)-A-S-H gel.RSM optimization facilitates the synergistic utilization of multi-solid wastes,ensuring an even distribution of gel and filler.This research establishes a theoretical framework for optimizing the preparation parameters of multi-solid wastes-based geopolymer and its subsequent applications;it holds significant scientific implications for the circular economy,resource transformation,and environmental conservation.展开更多
Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly acti...Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly active ORR electrocatalysts with superior kinetics hinders progress in this field.Herein,we report the Fe/Ni dual single-atomic sites anchored by commercial carbon black(Fe/Ni-N/CB)using rigid ligand confined and high-temperature shock(HTS)strategy in less than 0.5 s.Theoretical calculation reveals that singleatomic Fe is the real active site.Single-atomic Fe and Ni species in Fe/Ni-N/CB synergistically accelerate the kinetics of ORR by reducing the energy barrier of the rate-determining step.A large half-wave potential(E_(1/2))of 0.907 V is achieved in 0.1 M KOH aqueous solution.The assembled aqueous Zn-air battery(A-ZAB)with Fe/Ni-N/CB cathode presents remarkable charge-discharge cycling stability for over 650 h without voltage gap degradation.The quasi-solid-state Zn-air battery(QSS-ZAB)exhibits excellent reversibility over a 150-h operation at 0.5 mA·cm^(-2) with negligible energy conversion efficiency recession.Impressively,Fe/Ni-N/CB||RuO_(2)chloralkali flow cell exhibits a low cell voltage of 1.60 V at a large current density of 300 mA·cm^(-2) at 80℃,and demonstrates exceptional durability with 7% current density decay over 150 h of continuous operation at 100 mA·cm^(-2).Fe/Ni-N/CB||RuO_(2)achieves near-ideal caustic current efficiency(~97.2%)at the current density of 300 mA·cm^(-2).This work provides a rapid and economical synthesis technique for the synthesis of catalysts at the atomic scale while demonstrating significant potential for application in energy-saving chlor-alkali electrolyzer.展开更多
Oxygen is one of the important substances for the survival of most life systems on the earth,and plateau and underground burrow systems are two typical hypoxic environments.Small mammals living in hypoxic environments...Oxygen is one of the important substances for the survival of most life systems on the earth,and plateau and underground burrow systems are two typical hypoxic environments.Small mammals living in hypoxic environments have evolved different adaptation strategies,which include increased oxygen delivery,metabolic regulation of physiological responses and other physiological responses that change tissue oxygen utilization.Multiomics predictions have also shown that these animals have evolved different adaptations to extreme environments.In particular,vascular endothelial growth factor(VEGF)and erythropoietin(EPO),which have specific functions in the control of O_(2) delivery,have evolved adaptively in small mammals in hypoxic environments.Naked mole-rats and blind mole-rats are typical hypoxic model animals as they have some resistance to cancer.This review primarily summarizes the main living environment of hypoxia tolerant small mammals,as well as the changes of phenotype,physiochemical characteristics and gene expression mode of their long-term living in hypoxia environment.展开更多
Numerous field tests indicate that the soilestructure interaction （SSI） has a significant impact on thedynamic characteristics of super-tall buildings, which may lead to unexpected structural seismic responsesand/or...Numerous field tests indicate that the soilestructure interaction （SSI） has a significant impact on thedynamic characteristics of super-tall buildings, which may lead to unexpected structural seismic responsesand/or failure. Taking the Shanghai Tower with a total height of 632 m as the research object, thesubstructure approach is used to simulate the SSI effect on the seismic responses of Shanghai Tower. Therefined finite element （FE） model of the superstructure of Shanghai Tower and the simplified analyticalmodel of the foundation and adjacent soil are established. Subsequently, the collapse process of ShanghaiTower taking into account the SSI is predicted, as well as its final collapse mechanism. The influences ofthe SSI on the collapse resistance capacity and failure sequences are discussed. The results indicate that,when considering the SSI, the fundamental period of Shanghai Tower has been extended significantly,and the collapse margin ratio has been improved, with a corresponding decrease of the seismic demand.In addition, the SSI has some impact on the failure sequences of Shanghai Tower subjected to extremeearthquakes, but a negligible impact on the final failure modes. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.展开更多
The novel electronic properties of bilayer graphene can be fine-tuned via twisting,which may induce flat bands around the Fermi level with nontrivial topology.In general,the band structure of such twisted bilayer grap...The novel electronic properties of bilayer graphene can be fine-tuned via twisting,which may induce flat bands around the Fermi level with nontrivial topology.In general,the band structure of such twisted bilayer graphene(TBG)can be theoretically obtained by using first-principles calculations,tight-binding method,or continuum model,which are either computationally demanding or parameters dependent.In this work,by using the sure independence screening sparsifying operator method,we propose a physically interpretable three-dimensional(3D)descriptor which can be utilized to readily obtain theΓ-point gap of TBG at arbitrary twist angles and different interlayer spacings.The strong predictive power of the descriptor is demonstrated by a high Pearson coefficient of 99%for both the training and testing data.To go further,we adopt the neural network algorithm to accurately probe the flat bands of TBG at various twist angles,which can accelerate the study of strong correlation physics associated with such a fundamental characteristic,especially for those systems with a larger number of atoms in the unit cell.展开更多
Hyperfluorescent organic light-emitting diodes(HF-OLEDs)approach has made it possible to achieve excellent device performance and color purity with low roll-off using noble-metal-free pure organic emitter.Despite sign...Hyperfluorescent organic light-emitting diodes(HF-OLEDs)approach has made it possible to achieve excellent device performance and color purity with low roll-off using noble-metal-free pure organic emitter.Despite significant progress,the performance of HF-OLEDs is still unsatisfactory due to the existence of a competitive dexter energy transfer(DET)pathway.In this contribution,two boron dipyrromethene(BODIPY)-based donor-acceptor emitters(BDP-C-Cz and BDP-N-Cz)with hybridized local and charge transfer characteristics(HLCT)are introduced in the HF-OLED to suppress the exciton loss by dexter mechanism,and a breakthrough performance with low-efficiency roll-off(0.3%)even at high brightness(1000 cd m^(-2))is achieved.It is demonstrated that the energy loss via the DET channel can be suppressed in HF-OLEDs utilizing the HLCT emitter,as the excitons from the dark triplet state of such emitters are funneled to its emissive singlet state following the hot-exciton mechanism.The developed HF-OLED device has realized a good maximum external quantum efficiency(EQE)of 19.25%at brightness of 1000 cd m^(-2)and maximum luminance over 60000 cd m^(-2),with an emission peak at 602 nm and Commission International de L'Eclairage(CIE)coordinates(0.57,0.41),which is among the best-achieved results in solution-processed HF-OLEDs.This work presents a viable methodology to suppress energy loss and achieve high performance in the HF-OLEDs.展开更多
Genome editing is revolutionizing plant research and crop breeding.Sequence-specific nucleases(SSNs)such as zinc finger nuclease(ZFN)and TAL effector nuclease(TALEN)have been used to create site-specific DNA double-st...Genome editing is revolutionizing plant research and crop breeding.Sequence-specific nucleases(SSNs)such as zinc finger nuclease(ZFN)and TAL effector nuclease(TALEN)have been used to create site-specific DNA double-strand breaks and to achieve precise DNA modifications by promoting homology-directed repair(HDR)(Steinert et al.,2016;Voytas,2013).Later,RNA-guided SSNs such as CRISPR-Cas9,Cas12a,Cas12b,and their variants were applied for genome editing in plants(Li et al.,2013;Nekrasov et alM 2013;Tang et al.,2017;Zhong et al.,2019;Ming et al.,2020;Tang et al.,2019).However,HDR relies on simultaneous delivery of SSNs and DNA donors,which has been challenging in plants(Steinert et al.,2016;Zhang et aL,2019).Another challenge for realizing efficient HDR in plants is that DNA repair favors nonhomologous end joining(NHEJ)pathways over HDR in most cell types(Puchta,2005;Qi et al.,2013).展开更多
Highly ordered poly crystalline Si nanowire arrays were synthesized in porous anodic aluminum oxide (AAO) templates by the chemical vapor deposition (CVD) method. The morphological structure, the crystal character of ...Highly ordered poly crystalline Si nanowire arrays were synthesized in porous anodic aluminum oxide (AAO) templates by the chemical vapor deposition (CVD) method. The morphological structure, the crystal character of Si nanowire arrays and the individual nanowire were analyzed by the transmission electron microscopy (TEM), scanning electron microscopy (SEM), atom force microscopy (AFM) and the X-ray diffraction spectrum (XRD), respectively. It is shown that most fabricated silicon nanowires (SiNWs) tend to be assembled parallelly in bundles and constructed with highly orientated arrays. This method provides a simple and low cost fabricating craftwork and the diameters and lengths of SiNWs can be controlled, the large area Si nanowire arrays can be achieved easily under such a way. The curling and twisting SiNWs are fewer than those by other synthesis methods.展开更多
Over the past few decades,molecular dynamics simulations and first-principles calculations have become two major approaches to predict the lattice thermal conductivity(κ_(L)),which are however limited by insufficient...Over the past few decades,molecular dynamics simulations and first-principles calculations have become two major approaches to predict the lattice thermal conductivity(κ_(L)),which are however limited by insufficient accuracy and high computational cost,respectively.To overcome such inherent disadvantages,machine learning(ML)has been successfully used to accurately predictκL in a high-throughput style.In this review,we give some introductions of recent ML works on the direct and indirect prediction ofκL,where the derivations and applications of data-driven models are discussed in details.A brief summary of current works and future perspectives are given in the end.展开更多
Background:Textbook outcome(TO)can guide decision-making among patients and clinicians during preoperative patient selection and postoperative quality improvement.We explored the factors associated with achieving a TO...Background:Textbook outcome(TO)can guide decision-making among patients and clinicians during preoperative patient selection and postoperative quality improvement.We explored the factors associated with achieving a TO for gallbladder carcinoma(GBC)after curative-intent resection and analyzed the effect of adjuvant chemotherapy(ACT)on TO and non-TO patients.Methods:A total of 540 patients who underwent curative-intent resection for GBC at the Department of Hepatobiliary Surgery of the First Affiliated Hospital of Xi’an Jiaotong University from January 2011 to December 2020 were retrospectively analyzed.Multivariable logistic regression was used to investigate the factors associated with TO.Results:Among 540 patients with GBC who underwent curative-intent resection,223 patients(41.3%)achieved a TO.The incidence of TO ranged from 19.0%to 51.0%across the study period,with a slightly increasing trend over the study period.The multivariate analysis showed that non-TO was an independent risk factor for prognosis among GBC patients after resection(P=0.003).Age≤60 years(P=0.016),total bilirubin(TBIL)level≤34.1 mmol/L(P<0.001),well-differentiated tumor(P=0.008),no liver involvement(P<0.001),and T1-2 stage disease(P=0.006)were independently associated with achieving a TO for GBC after resection.Before and after propensity score matching(PSM),the overall survival outcomes of non-TO GBC patients who received ACT and those who did not were statistically significant;ACT improved the prognosis of patients in the non-TO group(P<0.05).Conclusion:Achieving a TO is associated with a better long-term prognosis among GBC patients after curative-intent resection,and ACT can improve the prognosis of those with non-TO.展开更多
Accurate evaluation of lattice thermal conductivity is usually a tough task from the theoretical side,especially for alloyed systems with fractional stoichiometry.Using the tetradymite family as a prototypical class o...Accurate evaluation of lattice thermal conductivity is usually a tough task from the theoretical side,especially for alloyed systems with fractional stoichiometry.Using the tetradymite family as a prototypical class of examples,we propose a reliable approach for rapid prediction on the lattice thermal conductivity at arbitrary composition by utilizing the concept of configurational entropy.Instead of performing time-consuming first-principles calculations,the lattice thermal conductivities of any alloyed tetradymites can be readily obtained from a few samples with integer stoichiometry.The strong predictive power is demonstrated by good agreement between our results and those reported experimentally.In principle,such an effective method can be applicable to any other material families,which is very beneficial for high-throughput design of systems with desired thermal conductivity.展开更多
Ten-eleven translocation 2(TET2)functions as a methylcytosine dioxygenase that catalyzes the iterative oxidation of 5-methylcytosine to 5-hydroxymethylcytosine,5-formylcytosine and 5-carboxylcytosine.TET2 has been sho...Ten-eleven translocation 2(TET2)functions as a methylcytosine dioxygenase that catalyzes the iterative oxidation of 5-methylcytosine to 5-hydroxymethylcytosine,5-formylcytosine and 5-carboxylcytosine.TET2 has been shown to be crucial for the maintenance and differentiation of hematopoietic stem cells,and its deletion and/or mutations results in the expansion of HSPCs,and leads to hematological malignancies.TET2 mutations were found in a variety of hematological disorders such as CMML(60%),MDS(30%),MPN(13%)and AML(20%).Interestingly,it was shown that CMML patients with TET2 mutation exhibited fewer platelets than CMML patients without TET2 mutation.However,the role and function of TET2 in platelet hemostasis and thrombogenesis is not well defined.Here in this study,using a genetically engineered Tet2 deletion mouse model,we found that the absence of Tet2 caused a decrease in the proportion of MEP cells and hyperploid megakaryocytes.Additionally,Tet2-deficient mice displayed impaired platelet activation and aggregation under stimulation of ADP and low concentrations of thrombin,although the modestly compromised platelet function and MEP differentiation in Tet2-deficient mice could be compensated without affecting blood coagulation function.Our study indicate that Tet2 deficiency leads to mild impairment of platelet function and thrombopoiesis in mice.展开更多
文摘Based on questionnaire data from Niutouzhen Village Units 1-7 in Shuangwangcheng Economic Zone,Shouguang City,Shandong Province,this study employs a binary logistic regression model to explore the factors influencing farmers'willingness to transfer farmland,and uses SPSS 27.0 software to perform regression analysis on the data.The results indicate that farmers'educational level,age of the household head,and contracted land area have a positive influence on farmers'willingness to transfer farmland at the 0.05 significance level,while annual household income has a positive influence at the 0.10 significance level.Furthermore,based on the regression analysis results,measures are proposed,including establishing and improving the rural land transfer compensation mechanism,enhancing publicity for land transfer,refining land transfer laws and regulations,optimizing the rural social security system,and actively expanding non-agricultural employment channels.These measures are intended to provide references for promoting farmland transfer work in Shouguang City.
基金supported by the Fundamental Research Funds for the Central Universities,China(No.104972025RSCrc0005)the Science and Technology Project of Shaanxi Yanchang Petroleum(Group)Co.,LTD,China(No.yc-whlg-2023ky-03)。
文摘The escalating production of industrial solid waste,combined with the dwindling availability of natural resources,has intensified the focus on waste recycling.However,the heterogeneity and complexity of waste pose significant challenges to determining process parameters.In this study,burnt coal cinder(BCC),granite powder(GP),and high-calcium fly ash(Class-C FA)were used as raw materials,and the response surface methodology(RSM)and single-factor experiments were applied to optimize the process parameters for geopolymer preparation.The optimized precursor powder composition was determined to be a mass ratio of 1.6:0.9:7.3 for BCC,GP,and Class-C FA.The NaOH-precursor powder ratio and liquid-solid ratio were adjusted to 0.084 and 0.222,respectively.The curing condition was set at 80℃ for 24 h.The resulting 28 d-aged multi-solid wastes-based geopolymer exhibited a high compressive strength of61.34 MPa.The microstructure,mineral phase,and atomic bonding of geopolymers were investigated using X-ray diffraction(XRD),thermal analysis(TA),Fourier transform infrared spectroscopy(FTIR),and scanning electron microscopy with energy dispersive spectroscopy(SEM-EDS).Findings indicate that the compressive strength of geopolymer is most significantly influenced by the Class-C FA,followed by BCC.Furthermore,a minor addition of GP can optimize the structural density of the geopolymer.The Ca present in the Class-C FA participates in the geopolymerization,forming a hybrid N-(C)-A-S-H gel.RSM optimization facilitates the synergistic utilization of multi-solid wastes,ensuring an even distribution of gel and filler.This research establishes a theoretical framework for optimizing the preparation parameters of multi-solid wastes-based geopolymer and its subsequent applications;it holds significant scientific implications for the circular economy,resource transformation,and environmental conservation.
基金supported financially by the National Natural Science Foundation of China(No.52172208)Taishan Scholar Young Talent Program(No.tsqn202306216)Shandong Excellent Young Scientists Fund Program(Overseas,2023HWYQ‑091).
文摘Oxygen reduction reaction(ORR)is crucial for Znair batteries,while also serves as a core electrochemical process in oxygen depolarized cathodes(ODCs)for chlor-alkali electrolysis.The lack of cost-effective,highly active ORR electrocatalysts with superior kinetics hinders progress in this field.Herein,we report the Fe/Ni dual single-atomic sites anchored by commercial carbon black(Fe/Ni-N/CB)using rigid ligand confined and high-temperature shock(HTS)strategy in less than 0.5 s.Theoretical calculation reveals that singleatomic Fe is the real active site.Single-atomic Fe and Ni species in Fe/Ni-N/CB synergistically accelerate the kinetics of ORR by reducing the energy barrier of the rate-determining step.A large half-wave potential(E_(1/2))of 0.907 V is achieved in 0.1 M KOH aqueous solution.The assembled aqueous Zn-air battery(A-ZAB)with Fe/Ni-N/CB cathode presents remarkable charge-discharge cycling stability for over 650 h without voltage gap degradation.The quasi-solid-state Zn-air battery(QSS-ZAB)exhibits excellent reversibility over a 150-h operation at 0.5 mA·cm^(-2) with negligible energy conversion efficiency recession.Impressively,Fe/Ni-N/CB||RuO_(2)chloralkali flow cell exhibits a low cell voltage of 1.60 V at a large current density of 300 mA·cm^(-2) at 80℃,and demonstrates exceptional durability with 7% current density decay over 150 h of continuous operation at 100 mA·cm^(-2).Fe/Ni-N/CB||RuO_(2)achieves near-ideal caustic current efficiency(~97.2%)at the current density of 300 mA·cm^(-2).This work provides a rapid and economical synthesis technique for the synthesis of catalysts at the atomic scale while demonstrating significant potential for application in energy-saving chlor-alkali electrolyzer.
基金This work was supported by the National Natural Science Foundation of China,Grant No.U2004152.
文摘Oxygen is one of the important substances for the survival of most life systems on the earth,and plateau and underground burrow systems are two typical hypoxic environments.Small mammals living in hypoxic environments have evolved different adaptation strategies,which include increased oxygen delivery,metabolic regulation of physiological responses and other physiological responses that change tissue oxygen utilization.Multiomics predictions have also shown that these animals have evolved different adaptations to extreme environments.In particular,vascular endothelial growth factor(VEGF)and erythropoietin(EPO),which have specific functions in the control of O_(2) delivery,have evolved adaptively in small mammals in hypoxic environments.Naked mole-rats and blind mole-rats are typical hypoxic model animals as they have some resistance to cancer.This review primarily summarizes the main living environment of hypoxia tolerant small mammals,as well as the changes of phenotype,physiochemical characteristics and gene expression mode of their long-term living in hypoxia environment.
基金the financial support received from the National Nature Science Foundation of China (Nos.51222804,91315301)the Beijing Natural Science Foundation (No.8142024)the Fok Ying Dong Education Foundation (No.131071)
文摘Numerous field tests indicate that the soilestructure interaction （SSI） has a significant impact on thedynamic characteristics of super-tall buildings, which may lead to unexpected structural seismic responsesand/or failure. Taking the Shanghai Tower with a total height of 632 m as the research object, thesubstructure approach is used to simulate the SSI effect on the seismic responses of Shanghai Tower. Therefined finite element （FE） model of the superstructure of Shanghai Tower and the simplified analyticalmodel of the foundation and adjacent soil are established. Subsequently, the collapse process of ShanghaiTower taking into account the SSI is predicted, as well as its final collapse mechanism. The influences ofthe SSI on the collapse resistance capacity and failure sequences are discussed. The results indicate that,when considering the SSI, the fundamental period of Shanghai Tower has been extended significantly,and the collapse margin ratio has been improved, with a corresponding decrease of the seismic demand.In addition, the SSI has some impact on the failure sequences of Shanghai Tower subjected to extremeearthquakes, but a negligible impact on the final failure modes. 2014 Institute of Rock and Soil Mechanics, Chinese Academy of Sciences. Production and hosting byElsevier B.V. All rights reserved.
基金the National Natural Science Foundation of China(Grant No.62074114)。
文摘The novel electronic properties of bilayer graphene can be fine-tuned via twisting,which may induce flat bands around the Fermi level with nontrivial topology.In general,the band structure of such twisted bilayer graphene(TBG)can be theoretically obtained by using first-principles calculations,tight-binding method,or continuum model,which are either computationally demanding or parameters dependent.In this work,by using the sure independence screening sparsifying operator method,we propose a physically interpretable three-dimensional(3D)descriptor which can be utilized to readily obtain theΓ-point gap of TBG at arbitrary twist angles and different interlayer spacings.The strong predictive power of the descriptor is demonstrated by a high Pearson coefficient of 99%for both the training and testing data.To go further,we adopt the neural network algorithm to accurately probe the flat bands of TBG at various twist angles,which can accelerate the study of strong correlation physics associated with such a fundamental characteristic,especially for those systems with a larger number of atoms in the unit cell.
基金supported by Guangdong Foundation of Basic and Applied Basic Research(2019B1515120023,2022B1515020041)National Natural Science Foundation of China(21975053,21975055,U2001222)for financial support
文摘Hyperfluorescent organic light-emitting diodes(HF-OLEDs)approach has made it possible to achieve excellent device performance and color purity with low roll-off using noble-metal-free pure organic emitter.Despite significant progress,the performance of HF-OLEDs is still unsatisfactory due to the existence of a competitive dexter energy transfer(DET)pathway.In this contribution,two boron dipyrromethene(BODIPY)-based donor-acceptor emitters(BDP-C-Cz and BDP-N-Cz)with hybridized local and charge transfer characteristics(HLCT)are introduced in the HF-OLED to suppress the exciton loss by dexter mechanism,and a breakthrough performance with low-efficiency roll-off(0.3%)even at high brightness(1000 cd m^(-2))is achieved.It is demonstrated that the energy loss via the DET channel can be suppressed in HF-OLEDs utilizing the HLCT emitter,as the excitons from the dark triplet state of such emitters are funneled to its emissive singlet state following the hot-exciton mechanism.The developed HF-OLED device has realized a good maximum external quantum efficiency(EQE)of 19.25%at brightness of 1000 cd m^(-2)and maximum luminance over 60000 cd m^(-2),with an emission peak at 602 nm and Commission International de L'Eclairage(CIE)coordinates(0.57,0.41),which is among the best-achieved results in solution-processed HF-OLEDs.This work presents a viable methodology to suppress energy loss and achieve high performance in the HF-OLEDs.
文摘Genome editing is revolutionizing plant research and crop breeding.Sequence-specific nucleases(SSNs)such as zinc finger nuclease(ZFN)and TAL effector nuclease(TALEN)have been used to create site-specific DNA double-strand breaks and to achieve precise DNA modifications by promoting homology-directed repair(HDR)(Steinert et al.,2016;Voytas,2013).Later,RNA-guided SSNs such as CRISPR-Cas9,Cas12a,Cas12b,and their variants were applied for genome editing in plants(Li et al.,2013;Nekrasov et alM 2013;Tang et al.,2017;Zhong et al.,2019;Ming et al.,2020;Tang et al.,2019).However,HDR relies on simultaneous delivery of SSNs and DNA donors,which has been challenging in plants(Steinert et al.,2016;Zhang et aL,2019).Another challenge for realizing efficient HDR in plants is that DNA repair favors nonhomologous end joining(NHEJ)pathways over HDR in most cell types(Puchta,2005;Qi et al.,2013).
基金This work was supported by the National Natural Science Foundation of China (Grant Nos. 69890220 and 69871013).
文摘Highly ordered poly crystalline Si nanowire arrays were synthesized in porous anodic aluminum oxide (AAO) templates by the chemical vapor deposition (CVD) method. The morphological structure, the crystal character of Si nanowire arrays and the individual nanowire were analyzed by the transmission electron microscopy (TEM), scanning electron microscopy (SEM), atom force microscopy (AFM) and the X-ray diffraction spectrum (XRD), respectively. It is shown that most fabricated silicon nanowires (SiNWs) tend to be assembled parallelly in bundles and constructed with highly orientated arrays. This method provides a simple and low cost fabricating craftwork and the diameters and lengths of SiNWs can be controlled, the large area Si nanowire arrays can be achieved easily under such a way. The curling and twisting SiNWs are fewer than those by other synthesis methods.
基金We thank financial support from the National Natural Science Foundation of China(Grant No.62074114).
文摘Over the past few decades,molecular dynamics simulations and first-principles calculations have become two major approaches to predict the lattice thermal conductivity(κ_(L)),which are however limited by insufficient accuracy and high computational cost,respectively.To overcome such inherent disadvantages,machine learning(ML)has been successfully used to accurately predictκL in a high-throughput style.In this review,we give some introductions of recent ML works on the direct and indirect prediction ofκL,where the derivations and applications of data-driven models are discussed in details.A brief summary of current works and future perspectives are given in the end.
基金supported by grants from the National Natural Science Foundation of China(No.62076194)the Key Research and Development Program of Shaanxi Province(Nos.2021-SF-016,2022-SF-410,and 2022-SF-606)+1 种基金the Central University Basic Research Business Fund(No.xzy012020113)the Clinical Research Fund of the First Affiliated Hospital of Xi’an Jiaotong University(No.XJTU1AF-CRF-2018-022).
文摘Background:Textbook outcome(TO)can guide decision-making among patients and clinicians during preoperative patient selection and postoperative quality improvement.We explored the factors associated with achieving a TO for gallbladder carcinoma(GBC)after curative-intent resection and analyzed the effect of adjuvant chemotherapy(ACT)on TO and non-TO patients.Methods:A total of 540 patients who underwent curative-intent resection for GBC at the Department of Hepatobiliary Surgery of the First Affiliated Hospital of Xi’an Jiaotong University from January 2011 to December 2020 were retrospectively analyzed.Multivariable logistic regression was used to investigate the factors associated with TO.Results:Among 540 patients with GBC who underwent curative-intent resection,223 patients(41.3%)achieved a TO.The incidence of TO ranged from 19.0%to 51.0%across the study period,with a slightly increasing trend over the study period.The multivariate analysis showed that non-TO was an independent risk factor for prognosis among GBC patients after resection(P=0.003).Age≤60 years(P=0.016),total bilirubin(TBIL)level≤34.1 mmol/L(P<0.001),well-differentiated tumor(P=0.008),no liver involvement(P<0.001),and T1-2 stage disease(P=0.006)were independently associated with achieving a TO for GBC after resection.Before and after propensity score matching(PSM),the overall survival outcomes of non-TO GBC patients who received ACT and those who did not were statistically significant;ACT improved the prognosis of patients in the non-TO group(P<0.05).Conclusion:Achieving a TO is associated with a better long-term prognosis among GBC patients after curative-intent resection,and ACT can improve the prognosis of those with non-TO.
基金We thank financial support from the National Natural Science Foundation of China(Grant Nos.62074114,51772220,and 12004368).
文摘Accurate evaluation of lattice thermal conductivity is usually a tough task from the theoretical side,especially for alloyed systems with fractional stoichiometry.Using the tetradymite family as a prototypical class of examples,we propose a reliable approach for rapid prediction on the lattice thermal conductivity at arbitrary composition by utilizing the concept of configurational entropy.Instead of performing time-consuming first-principles calculations,the lattice thermal conductivities of any alloyed tetradymites can be readily obtained from a few samples with integer stoichiometry.The strong predictive power is demonstrated by good agreement between our results and those reported experimentally.In principle,such an effective method can be applicable to any other material families,which is very beneficial for high-throughput design of systems with desired thermal conductivity.
基金This work was partially supported by the funds from the CAMS Innovation Fund for Medical Sciences(2016-I2M-1-017 and 2017-I2M-3-015)National Natural Science Foundation of China(81629001,81421002,81600136,81770105,81970149).
文摘Ten-eleven translocation 2(TET2)functions as a methylcytosine dioxygenase that catalyzes the iterative oxidation of 5-methylcytosine to 5-hydroxymethylcytosine,5-formylcytosine and 5-carboxylcytosine.TET2 has been shown to be crucial for the maintenance and differentiation of hematopoietic stem cells,and its deletion and/or mutations results in the expansion of HSPCs,and leads to hematological malignancies.TET2 mutations were found in a variety of hematological disorders such as CMML(60%),MDS(30%),MPN(13%)and AML(20%).Interestingly,it was shown that CMML patients with TET2 mutation exhibited fewer platelets than CMML patients without TET2 mutation.However,the role and function of TET2 in platelet hemostasis and thrombogenesis is not well defined.Here in this study,using a genetically engineered Tet2 deletion mouse model,we found that the absence of Tet2 caused a decrease in the proportion of MEP cells and hyperploid megakaryocytes.Additionally,Tet2-deficient mice displayed impaired platelet activation and aggregation under stimulation of ADP and low concentrations of thrombin,although the modestly compromised platelet function and MEP differentiation in Tet2-deficient mice could be compensated without affecting blood coagulation function.Our study indicate that Tet2 deficiency leads to mild impairment of platelet function and thrombopoiesis in mice.
