In recent years,the rapid development of artificial intelligence(AI)technology has been driving profound transformations in higher education.As a fundamental course in science and engineering disciplines,Advanced Math...In recent years,the rapid development of artificial intelligence(AI)technology has been driving profound transformations in higher education.As a fundamental course in science and engineering disciplines,Advanced Mathematics plays a crucial role in cultivating students’logical thinking and innovative capabilities.However,the current teaching models exhibit significant shortcomings in fostering students’ability to identify and solve problems,primarily reflected in the monotony of teaching content,the limitations of students’thinking,and the constraints of instructional methods.In response to these issues,this paper proposes an AI-based teaching approach for Advanced Mathematics.By utilizing scenario simulations to guide students in discovering problems and employing modeling tools to assist them in solving problems in real time,the study constructs a comprehensive teaching model that spans the entire process from problem identification to problem resolution.Research findings indicate that the application of AI technology can effectively enhance students’abilities in problem awareness,logical reasoning,and creative thinking.This study provides both theoretical support and practical reference for the reform of Advanced Mathematics education and the innovation of higher-level talent cultivation models.展开更多
As a tool for quantifying individuals’visual attention and information processing,eye-tracking technology is gradually being applied in the reform of higher education.This paper focuses on issues in university mathem...As a tool for quantifying individuals’visual attention and information processing,eye-tracking technology is gradually being applied in the reform of higher education.This paper focuses on issues in university mathematics teaching,such as heavy cognitive load,delayed feedback,and insufficient adaptability.Based on theories of cognitive psychology,the study explores application pathways of this technology in cognitive diagnosis,instructional optimization,classroom regulation,personalized support,and teaching assessment.Research shows that eye-tracking data can reveal key cognitive features during the learning process,enhance the visualization of instructional feedback,and improve the scientific basis of decision-making.This provides both theoretical support and practical reference for data-driven and precise transformation in university mathematics education.展开更多
Lithium sulfur batteries with high energy density are thought to be the most potential energy storage technology that can be commercialized.However,the shuttle effect of polysulfides deteriorates its electrochemical p...Lithium sulfur batteries with high energy density are thought to be the most potential energy storage technology that can be commercialized.However,the shuttle effect of polysulfides deteriorates its electrochemical performance.Herein,a novel Co_(9)S_(8)nanostructure derived from metal organic framework material(MOF)was explored by simple liquid phase reaction and heat vulcanization of2-methylimidazole and Co(NO_(3))_(2)·6 H_(2)O on the surface of the original PP separator.The Co_(9)S_(8)nano-flower cluster array wall was vertically and closely arranged with the thickness of 200 nm,and the polysulfide can be adsorbed by its physical and chemical action to slow down the"shuttle effect".It is found that the cell with the modified separator can achieve an ideal discharge capacity of about 600 mAh/g at 1 C.The specific capacity is maintained at 500 mAh/g after 200 cycles,with only 0.11%of capacity decay per cycle.It provides a new way for the utilization of MOF material derivatives to modify the separator in order to improve the electrochemical performance of lithium-sulfur batteries.展开更多
Chilling has a critical role in the growth and development of perennial plants.The chilling requirement(CR)for dormancy breaking largely depends on the species.However,global warming is expected to negatively affect c...Chilling has a critical role in the growth and development of perennial plants.The chilling requirement(CR)for dormancy breaking largely depends on the species.However,global warming is expected to negatively affect chilling accumulation and dormancy release in a wide range of perennial plants.Here,we used Chimonanthus praecox as a model to investigate the CR for dormancy breaking under natural and artificial conditions.We determined the minimum CR(570 chill units,CU)needed for chilling-induced dormancy breaking and analyzed the transcriptomes and proteomes of flowering and non-flowering flower buds(FBs,anther and ovary differentiation completed)with different CRs.The concentrations of ABA and GA3 in the FBs were also determined using HPLC.The results indicate that chilling induced an upregulation of ABA levels and significant downregulation of SHORT VEGETATIVE PHASE(SVP)and FLOWERING LOCUS T(FT)homologs at the transcript level in FBs when the accumulated CR reached 570 CU(IB570)compared to FBs in November(FB.Nov,CK)and nF16(non-flowering FBs after treatment at 16℃for−300 CU),which suggested that dormancy breaking of FBs could be regulated by the ABA-mediated SVP-FT module.Overexpression in Arabidopsis was used to confirm the function of candidate genes,and early flowering was induced in 35S::CpFT1 transgenic lines.Our data provide insight into the minimum CR(570 CU)needed for chilling-induced dormancy breaking and its underlying regulatory mechanism in C.praecox,which provides a new tool for the artificial regulation of flowering time and a rich gene resource for controlling chilling-induced blooming.展开更多
Plant Dna JA proteins act as molecular chaperones in response to environmental stressors.The purpose of this study was to characterize the function and regulatory mechanisms of Dna JA genes in soybean.Gene expression ...Plant Dna JA proteins act as molecular chaperones in response to environmental stressors.The purpose of this study was to characterize the function and regulatory mechanisms of Dna JA genes in soybean.Gene expression profiles in various soybean tissues at various stages of development indicated that Gm Dna JAs function in the coordination of stress and plant hormone responses.Gm Dna JA6 was identified as a candidate regulator of saline and alkaline stress resistance and Gm Dna JA6 overexpression lines showed increased soybean saline and alkaline tolerance.Dna J interacted with Hsp70,and Gm Hsp70 increased the saline and alkaline tolerance of plants with chimeric soybean hairy roots.展开更多
Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from...Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from 2020 to 2021 for 6 patients who underwent correction using a stripshaped cymba conchae orthosis. The indications, corrective effects, and complications associated with use of the orthosis were analyzed. Results: There were four indications for treatment: cryptotia with helix adhesion;cryptotia with grade I microtia;cryptotia with excessive helix thickness;and auricular deformity beyond the treatment time window(≥6 months). Excellent corrective effects were observed in all 6 patients. Complications occurred in one patient, who recovered after symptomatic treatment. Conclusion: The use of a strip-shaped cymba conchae orthosis alone or combined with a U-shaped helix orthosis presents a feasible approach for correcting complex auricular deformities or deformities beyond the treatment time window in pediatric patients.展开更多
[Objectives]This study was conducted to establish a qualitative method for rapid detection of pesticide residues in feed.[Methods]A rapid screening method for 82 pesticide residues in feed was established using ultra ...[Objectives]This study was conducted to establish a qualitative method for rapid detection of pesticide residues in feed.[Methods]A rapid screening method for 82 pesticide residues in feed was established using ultra liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF-MS)combined with optimized pretreatment methods.[Results]Feed samples were extracted with 0.2%formic acid-acetonitrile solution,shaken,centrifuged,and re-centrifuged,and the supernatant was filtered with a 0.22μm filter membrane for determination.The samples were separated on a Waters ACQUITY UPLC HSS T3 chromatographic column(2.1 mm×50 mm,1.8μm),and subjected to gradient elution with methanol-water solution as the mobile phase,and scanning was performed in ESI+mode.82 compounds could be accurately qualitatively detected in 13 min.[Conclusions]This method is simple to operate,time-saving,and can be applied to rapid screening of large-scale feed.This study provides a theoretical basis for the development of new methods in the future.展开更多
Forest cover change is considered one of the serious issues in the last several decades for the global environment. This scenario has mainly depended to ever-increasing socio-economic activities. The present article h...Forest cover change is considered one of the serious issues in the last several decades for the global environment. This scenario has mainly depended to ever-increasing socio-economic activities. The present article has revealed major changes of VFC in relation to human activities during the years of 2000 to 2010 in the Guangdong province of China. The data derived using the NDVIimages. The analysis covered the growing season which consisted of seven months (April to October) annually. VFC (Vegetation Fractional Cover) was successfully calculated from NDVI images and VFC levels were defined in four levels. Levels IV and I had the highest and lowest annual changes. Areas at risk of desertification and difference coverage were determined by Hot Spot and Cold Spot analyzing. Mean of total VFC was evaluated 0.783 and Moran’s I statistic calculated for years separately. Additionally, Light Index achieved of DMSP/OLS data annually. The results show that VFC and Light Index have an upward trend, which means that development of social economy leads to increasing awareness of the importance of environmental protection and sustainable development. Hereof, we witness seven-year increase of VFC during the eleven years. The correlation co-efficient shows that Light Index is suitable index for evaluating diving forces. Time series modeling confirms that there is strong inverse relationship between the VFC and Light Index in most cases. This means with increasing Light Index, VFC decreases. Finally, driving forces of VFC variation show that forest cover change scenario is more under the influence of the human activities.展开更多
The nickel-base alloy is one of the leading candidate materials for generation IV nuclear reactor pressure vessel.To evaluate its stability of helium damage and retention,helium ions with different energy of 80 keV an...The nickel-base alloy is one of the leading candidate materials for generation IV nuclear reactor pressure vessel.To evaluate its stability of helium damage and retention,helium ions with different energy of 80 keV and 180 keV were introduced by ion implantation to a certain dose(peak displacement damage 1-10 dpa).Then thermal desorption spectroscopy(TDS)of helium atoms was performed to discuss the helium desorption characteristic and trapping sites.The desorption peaks shift to a lower temperature with increasing dpa for both 80 keV and 180 keV irradiation,reflecting the reduced diffusion activation energy and faster diffusion within the alloy.The main release peak temperature of 180 keV helium injection is relatively higher than that of 80 keV at the same influence,which is because the irradiation damage of 180 keV,helium formation and entrapment occur deeper.The broadening of the spectra corresponds to different helium trapping sites(He-vacancies,grain boundary)and desorption mechanisms(different Hen Vm size).The helium retention amount of 80 keV is lower than that of 180 keV,and a saturation limit associated with the irradiation of 80 keV has been reached.The relatively low helium retention proves the better resistance to helium bubbles formation and helium brittleness.展开更多
Soil microorganisms play critical roles in ecosystem function.However,the relative impact of the potassium(K)fertilizer gradient on the microbial community in wheat-maize double-cropping systems remains unclear.In thi...Soil microorganisms play critical roles in ecosystem function.However,the relative impact of the potassium(K)fertilizer gradient on the microbial community in wheat-maize double-cropping systems remains unclear.In this long-term field experiment(2008-2019),we researched bacterial and fungal diversity,composition,and community assemblage in the soil along a K fertilizer gradient in the wheat season(K0,no K fertilizer;K1,45 kg ha^(-1) K_(2)O;K_(2),90 kg ha^(-1)K_(2)O;K3,135 kg ha^(-1)K_(2)O)and in the maize season(K0,no K fertilizer;K_(1),150 kg ha^(-1) K_(2)O;K_(2),300 kg ha^(-1)K_(2)O;K_(3),450 kg ha^(-1)K_(2)O)using bacterial 16S rRNA and fungal internally transcribed spacer(ITS)data.We observed that environmental variables,such as mean annual soil temperature(MAT)and precipitation,available K,ammonium,nitrate,and organic matter,impacted the soil bacterial and fungal communities,and their impacts varied with fertilizer treatments and crop species.Furthermore,the relative abundance of bacteria involved in soil nutrient transformation(phylum Actinobacteria and class Alphaproteobacteria)in the wheat season was significantly increased compared to the maize season,and the optimal K fertilizer dosage(K2 treatment)boosted the relative bacterial abundance of soil nutrient transformation(genus Lactobacillus)and soil denitrification(phylum Proteobacteria)bacteria in the wheat season.The abundance of the soil bacterial community promoting root growth and nutrient absorption(genus Herbaspirillum)in the maize season was improved compared to the wheat season,and the K2 treatment enhanced the bacterial abundance of soil nutrient transformation(genus MND1)and soil nitrogen cycling(genus Nitrospira)genera in the maize season.The results indicated that the bacterial and fungal communities in the double-cropping system exhibited variable sensitivities and assembly mechanisms along a K fertilizer gradient,and microhabitats explained the largest amount of the variation in crop yields,and improved wheat?maize yields by 11.2-22.6 and 9.2-23.8%with K addition,respectively.These modes are shaped contemporaneously by the different meteorological factors and soil nutrient changes in the K fertilizer gradients.展开更多
The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achie...The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production.展开更多
Prion diseases are fatal neurodegenerative diseases that can cause severe dementia.The misfolding and accumulation of the prion peptide (PrP)_(106–126) is crucial,and this process is closely relevant to biological me...Prion diseases are fatal neurodegenerative diseases that can cause severe dementia.The misfolding and accumulation of the prion peptide (PrP)_(106–126) is crucial,and this process is closely relevant to biological membranes.However,how PrP_(106–126)aggregation is affected by the molecular chirality of phospholipid membrane is unknown.Thus,in this study,a pair of L-and D-aspartic acid (Asp)-modified 1,2-dipalmitoyl-sn–glycero-3-phosphoethanolamine (DPPE) were synthesized to construct chiral liposomes.We discover that L-Asp-DPPE liposomes strongly inhibit the oligomerization and amyloidogenesis of PrP_(106–126),whether acting on monomers or oligomers,which rescues cytotoxicity induced by PrP_(106–126).By comparison,D-Asp-DPPE liposomes inhibit peptide oligomerization only at a high concentration and cannot prevent amyloidogenesis when acting on oligomers,which lead to pronounced cytotoxicity.Apoptosis experiment,dynamic change of intracellular Ca^(2+)(_(i)Ca^(2+)) and Ca^(2+)release from endoplasmic reticulum(ER),reactive oxygen species (ROS) production,adsorption dynamics and affinity tests,and fluorescent imaging clearly disclose that molecular chirality of the liposomes dominates conformational transition of PrP_(106–126)from random coil to β-sheet,binding and adsorption of the monomers and oligomers,and subsequent fibrillation process,resulting in distinct inhibition effect in Ca^(2+)overload and release,ROS production and cell apoptosis.This work is the first to report that interfacial molecular chirality is a potentially crucial influence on the fibrillation process of PrP_(106–126) and its cell responses,whereas the convergence of chiral amino acids and liposomes can be considered potential inhibitors in prion diseases.展开更多
[Objectives]This study was conducted to develop an enzyme-linked immunoassay kit that can detect the residual amount of pentachloronitrobenzene in Penaeus vannamei.[Methods]This study was conducted to develop an enzym...[Objectives]This study was conducted to develop an enzyme-linked immunoassay kit that can detect the residual amount of pentachloronitrobenzene in Penaeus vannamei.[Methods]This study was conducted to develop an enzyme-linked immunoassay kit that can detect the residual amount of pentachloronitrobenzene in P.vannamei.[Results]The standard curve range of the kit was 0-8.1μg/L;the detection limit for P.vannamei was 0.912μg/kg;the recovery was 80.6%-103.5%;and the relative standard deviation range within batches was 5.3%-10.1%,and the relative standard deviation range between batches was 6.7%-8.1%.The specificity of the pentachloronitrobenzene monoclonal antibody was relatively good,and the cross-reaction rates with pentachlorophenol,hexachlorobenzene,tetrachlorophthalide,and chlorothalonil were low,all of which did not exceed 30%.The ELISA kit could be stored at 4℃for 12 months,showing good stability.[Conclusions]The detection kit has low cost,short time and small deviation,and is an ideal preliminary screening method.展开更多
Eutectic high-entropy alloys(EHEAs)that combine the advantages of HEAs and eutectic alloys are promising materials for high-temperature environments.However,the mechanical properties of currently developed EHEAs still...Eutectic high-entropy alloys(EHEAs)that combine the advantages of HEAs and eutectic alloys are promising materials for high-temperature environments.However,the mechanical properties of currently developed EHEAs still cannot meet the servicing requirements.Here,we propose a strategy to optimize the tensile properties in a Al_(21)Co_(19.5)Fe_(9.5)Ni_(50)EHEA by regulating the phase transformation and precipitation features.The results showed that the as-cast Al_(21)Co_(19.5)Fe_(9.5)Ni_(50)EHEA mainly consists of face-centered cubic(FCC)and B2 phases showing a lamellar morphology,and the FCC and B2 phases keep a stable K-S orientation relationship.Solution treatment at 900 and 1100°C followed by furnace cooling to room temperature leads to a significant precipitation of L1_(2)phases within the FCC phases.In the subsequent tensile deformation process,dispersed L1_(2)phases and the transformation from B2 to L1_(0)phases can significantly enhance the yield strength of the designed EHEA.Furthermore,solution treatment at the same temperature,followed by rapid water quenching,results in the appearance of numerous L1_(0)phases within the B2 phases.The transformation from L1_(0)to B2 phases during subsequent tensile deformation can make the B2 and FCC phases return to a K-S orientation relationship.This,in turn,reduces the tendency for dislocation pile-ups at the phase interfaces and improves the ductility.We believe that this work will provide some new references for designing EHEAs with excellent mechanical properties.展开更多
The TiNbV_(0.5)Ta_(0.5)Cr_(x)(x=0,0.1,0.2,0.5)refractory high-entropy alloys(RHEAs)with an excellent combination of ductility and strength were designed and prepared for high-temperature applications.The yield strengt...The TiNbV_(0.5)Ta_(0.5)Cr_(x)(x=0,0.1,0.2,0.5)refractory high-entropy alloys(RHEAs)with an excellent combination of ductility and strength were designed and prepared for high-temperature applications.The yield strength,ultimate tensile strength,and elongation of the TiNbV_(0.5)Ta_(0.5)Cr_(0.1) alloy were 878 MPa,928 MPa,and 21.6%,respectively.Important issues of microstructure evolution,precipitation process,and their impact on mechanical properties were concerned.Then,the effect of Cr content on the mechanical properties of TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys was evaluated through a quantitative analysis of the strengthening mechanism,which elucidated the trade-offrelationship between solid solution strengthening and precipitation strengthening in RHEA.The microstructure evolution of the TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys involved the formation and interconversion of titanium allotropes(α-Ti and β-Ti)and the precipitation of the Laves phase.Significant embrittlement was induced by the preferential precipitation of α-Ti on the grain boundary.The TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys exhibited an incubation period for Laves phase precipitation,which was related to the Cr content in the alloy.The Laves phase preferentially nucleated next to α-Ti due to the redistribution of elements during the α-Ti precipitation process.The precipitation of the Laves phase played an important role in enhancing the strength of the TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys.展开更多
The southwest mountainous area is a frequent debris flow disaster area in<span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> Chin...The southwest mountainous area is a frequent debris flow disaster area in<span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> China, which poses a serious threat to the regional roads and greatly affects the normal traffic operation and the safety of residents’ lives and property. The debris flow risk assessment of highway can quantify the threat degree of debris flow to the roads. In this paper, from the perspective of villages and towns, taking the upper reaches of Minjiang River as the research area, four factors including road network density, highway disaster resistance capacity, population density and highway cost are selected, and the weight is obtained by using entropy weight method, and the debris flow vulnerability evaluation results of highway are obtained by weighted calculation. Four indexes of debris flow density, shape factor, relative height difference and annual rainfall are selected to evaluate the debris flow hazard of highway by using the information method. Based on the vulnerability and hazard evaluation results, the ri</span><span style="font-family:Verdana;">sk of highway debris flow is evaluated, and the results are classified and</span><span style="font-family:Verdana;"> discussed. The results show that: the risk of debris flow on the upper reaches of Minjiang River is relatively low, the overall spatial distribution shows a trend of high in the East and low in the west, and the overall risk of township roads in Wenchuan county is the highest;The risk of debris flow is generally high within </span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">-10 to 30</span><span style="font-family:Verdana;"> km from the central fault zone of Longmenshan.</span></span></span></span>展开更多
基金supported by the 2023 Teaching Reform and Research Project of China University of Petroleum(Beijing),Karamay Campus(Grant No.JG2023048)the 2024 National Undergraduate Innovation and Entrepreneurship Training Program of China(Project No.202419414009)the 2024 General Program of the Natural Science Foundation of Xinjiang Uygur Autonomous Region(Grant No.2024D01A160).
文摘In recent years,the rapid development of artificial intelligence(AI)technology has been driving profound transformations in higher education.As a fundamental course in science and engineering disciplines,Advanced Mathematics plays a crucial role in cultivating students’logical thinking and innovative capabilities.However,the current teaching models exhibit significant shortcomings in fostering students’ability to identify and solve problems,primarily reflected in the monotony of teaching content,the limitations of students’thinking,and the constraints of instructional methods.In response to these issues,this paper proposes an AI-based teaching approach for Advanced Mathematics.By utilizing scenario simulations to guide students in discovering problems and employing modeling tools to assist them in solving problems in real time,the study constructs a comprehensive teaching model that spans the entire process from problem identification to problem resolution.Research findings indicate that the application of AI technology can effectively enhance students’abilities in problem awareness,logical reasoning,and creative thinking.This study provides both theoretical support and practical reference for the reform of Advanced Mathematics education and the innovation of higher-level talent cultivation models.
基金The 2024 Education and Teaching Reform Project,“Exploration and Practice of University Mathematics Teaching Reform Driven by Eye-Tracking Technology”(Project No.:JG2024047)。
文摘As a tool for quantifying individuals’visual attention and information processing,eye-tracking technology is gradually being applied in the reform of higher education.This paper focuses on issues in university mathematics teaching,such as heavy cognitive load,delayed feedback,and insufficient adaptability.Based on theories of cognitive psychology,the study explores application pathways of this technology in cognitive diagnosis,instructional optimization,classroom regulation,personalized support,and teaching assessment.Research shows that eye-tracking data can reveal key cognitive features during the learning process,enhance the visualization of instructional feedback,and improve the scientific basis of decision-making.This provides both theoretical support and practical reference for data-driven and precise transformation in university mathematics education.
基金supported by the Natural Science Foundation of Beijing(No.L182062)Organization Department of Beijing Talents Project(No.2018000021223ZK21)+1 种基金the Yue Qi Young Scholar Project of China University of Mining&Technology(Beijing)(No.2017QN17)the Fundamental Research Funds for the Central Universities(Nos.2020YJSJD01,2020XJJD01 and 2020YQJD05)。
文摘Lithium sulfur batteries with high energy density are thought to be the most potential energy storage technology that can be commercialized.However,the shuttle effect of polysulfides deteriorates its electrochemical performance.Herein,a novel Co_(9)S_(8)nanostructure derived from metal organic framework material(MOF)was explored by simple liquid phase reaction and heat vulcanization of2-methylimidazole and Co(NO_(3))_(2)·6 H_(2)O on the surface of the original PP separator.The Co_(9)S_(8)nano-flower cluster array wall was vertically and closely arranged with the thickness of 200 nm,and the polysulfide can be adsorbed by its physical and chemical action to slow down the"shuttle effect".It is found that the cell with the modified separator can achieve an ideal discharge capacity of about 600 mAh/g at 1 C.The specific capacity is maintained at 500 mAh/g after 200 cycles,with only 0.11%of capacity decay per cycle.It provides a new way for the utilization of MOF material derivatives to modify the separator in order to improve the electrochemical performance of lithium-sulfur batteries.
基金supported by grants from the Natural Science Foundation of Chongqing(No.cstc2020jcyj-msxmX1014)Fundamental Research Funds for the Central Universities(No.XDJK2020B059)+1 种基金National Natural Science Foundation of China(Grant No.31971711)Chongqing education committee project(CY200210,S202010635221).
文摘Chilling has a critical role in the growth and development of perennial plants.The chilling requirement(CR)for dormancy breaking largely depends on the species.However,global warming is expected to negatively affect chilling accumulation and dormancy release in a wide range of perennial plants.Here,we used Chimonanthus praecox as a model to investigate the CR for dormancy breaking under natural and artificial conditions.We determined the minimum CR(570 chill units,CU)needed for chilling-induced dormancy breaking and analyzed the transcriptomes and proteomes of flowering and non-flowering flower buds(FBs,anther and ovary differentiation completed)with different CRs.The concentrations of ABA and GA3 in the FBs were also determined using HPLC.The results indicate that chilling induced an upregulation of ABA levels and significant downregulation of SHORT VEGETATIVE PHASE(SVP)and FLOWERING LOCUS T(FT)homologs at the transcript level in FBs when the accumulated CR reached 570 CU(IB570)compared to FBs in November(FB.Nov,CK)and nF16(non-flowering FBs after treatment at 16℃for−300 CU),which suggested that dormancy breaking of FBs could be regulated by the ABA-mediated SVP-FT module.Overexpression in Arabidopsis was used to confirm the function of candidate genes,and early flowering was induced in 35S::CpFT1 transgenic lines.Our data provide insight into the minimum CR(570 CU)needed for chilling-induced dormancy breaking and its underlying regulatory mechanism in C.praecox,which provides a new tool for the artificial regulation of flowering time and a rich gene resource for controlling chilling-induced blooming.
基金financially supported by Natural Science Foundation of Heilongjiang(TD2022C003,JJ2022YX0475)National Key Research and Development Program of China(2021YFD1201104-02-02,2021YFF1001202)+1 种基金Backbone of Young Talent Scholar Project of Northeast Agricultural University(to Ying Zhao)the National Natural Science Foundation of China(U20A2027,31971899,32272093,32272072)。
文摘Plant Dna JA proteins act as molecular chaperones in response to environmental stressors.The purpose of this study was to characterize the function and regulatory mechanisms of Dna JA genes in soybean.Gene expression profiles in various soybean tissues at various stages of development indicated that Gm Dna JAs function in the coordination of stress and plant hormone responses.Gm Dna JA6 was identified as a candidate regulator of saline and alkaline stress resistance and Gm Dna JA6 overexpression lines showed increased soybean saline and alkaline tolerance.Dna J interacted with Hsp70,and Gm Hsp70 increased the saline and alkaline tolerance of plants with chimeric soybean hairy roots.
文摘Objective: This study aims to evaluate the efficacy and safety of using a strip-shaped cymba conchae orthosis for the nonsurgical correction of complex auricular deformities. Methods: Clinical data were collected from 2020 to 2021 for 6 patients who underwent correction using a stripshaped cymba conchae orthosis. The indications, corrective effects, and complications associated with use of the orthosis were analyzed. Results: There were four indications for treatment: cryptotia with helix adhesion;cryptotia with grade I microtia;cryptotia with excessive helix thickness;and auricular deformity beyond the treatment time window(≥6 months). Excellent corrective effects were observed in all 6 patients. Complications occurred in one patient, who recovered after symptomatic treatment. Conclusion: The use of a strip-shaped cymba conchae orthosis alone or combined with a U-shaped helix orthosis presents a feasible approach for correcting complex auricular deformities or deformities beyond the treatment time window in pediatric patients.
基金Supported by Key R&D Project in Hebei Province(19227516D)Hebei Provincial Phase II Modern Agricultural Industry Technology System Innovation Team Building Project(HBCT2018120207)+2 种基金Hebei Provincial Phase II Modern Agricultural Industry Technology System Forage Industry Innovation Team Building Project(HBCT2018160403)Tangshan Science and Technology Planning Project(21130243A)The Fourth Batch of High-end Talent Project in Hebei Province。
文摘[Objectives]This study was conducted to establish a qualitative method for rapid detection of pesticide residues in feed.[Methods]A rapid screening method for 82 pesticide residues in feed was established using ultra liquid chromatography coupled with quadrupole-time of flight mass spectrometry(UPLC-Q-TOF-MS)combined with optimized pretreatment methods.[Results]Feed samples were extracted with 0.2%formic acid-acetonitrile solution,shaken,centrifuged,and re-centrifuged,and the supernatant was filtered with a 0.22μm filter membrane for determination.The samples were separated on a Waters ACQUITY UPLC HSS T3 chromatographic column(2.1 mm×50 mm,1.8μm),and subjected to gradient elution with methanol-water solution as the mobile phase,and scanning was performed in ESI+mode.82 compounds could be accurately qualitatively detected in 13 min.[Conclusions]This method is simple to operate,time-saving,and can be applied to rapid screening of large-scale feed.This study provides a theoretical basis for the development of new methods in the future.
文摘Forest cover change is considered one of the serious issues in the last several decades for the global environment. This scenario has mainly depended to ever-increasing socio-economic activities. The present article has revealed major changes of VFC in relation to human activities during the years of 2000 to 2010 in the Guangdong province of China. The data derived using the NDVIimages. The analysis covered the growing season which consisted of seven months (April to October) annually. VFC (Vegetation Fractional Cover) was successfully calculated from NDVI images and VFC levels were defined in four levels. Levels IV and I had the highest and lowest annual changes. Areas at risk of desertification and difference coverage were determined by Hot Spot and Cold Spot analyzing. Mean of total VFC was evaluated 0.783 and Moran’s I statistic calculated for years separately. Additionally, Light Index achieved of DMSP/OLS data annually. The results show that VFC and Light Index have an upward trend, which means that development of social economy leads to increasing awareness of the importance of environmental protection and sustainable development. Hereof, we witness seven-year increase of VFC during the eleven years. The correlation co-efficient shows that Light Index is suitable index for evaluating diving forces. Time series modeling confirms that there is strong inverse relationship between the VFC and Light Index in most cases. This means with increasing Light Index, VFC decreases. Finally, driving forces of VFC variation show that forest cover change scenario is more under the influence of the human activities.
基金Project supported by Special Funds for Fundamental Research Funds for Central Universities,China(Grant Nos.2018 NTST29 and 2018 NTST04)the National Natural Science Foundation of China(Grant No.61176003)+1 种基金Chinese Postdoctoral Science Foundation(Grant No.2019M650524)Guangdong Province Key Area R&D Program,China(Grant No.2019B090909002)。
文摘The nickel-base alloy is one of the leading candidate materials for generation IV nuclear reactor pressure vessel.To evaluate its stability of helium damage and retention,helium ions with different energy of 80 keV and 180 keV were introduced by ion implantation to a certain dose(peak displacement damage 1-10 dpa).Then thermal desorption spectroscopy(TDS)of helium atoms was performed to discuss the helium desorption characteristic and trapping sites.The desorption peaks shift to a lower temperature with increasing dpa for both 80 keV and 180 keV irradiation,reflecting the reduced diffusion activation energy and faster diffusion within the alloy.The main release peak temperature of 180 keV helium injection is relatively higher than that of 80 keV at the same influence,which is because the irradiation damage of 180 keV,helium formation and entrapment occur deeper.The broadening of the spectra corresponds to different helium trapping sites(He-vacancies,grain boundary)and desorption mechanisms(different Hen Vm size).The helium retention amount of 80 keV is lower than that of 180 keV,and a saturation limit associated with the irradiation of 80 keV has been reached.The relatively low helium retention proves the better resistance to helium bubbles formation and helium brittleness.
基金funded by the National Key Research and Development Program of China(2023YFD150050504)the Key Research and Development Program of Shandong Province,China(2022SFGC0301)the Strategic Priority Research Program of the Chinese Academy of Sciences-Development and Application Technology of Special Package Fertilizer for Improving Albic Soil(XDA28100203)。
文摘Soil microorganisms play critical roles in ecosystem function.However,the relative impact of the potassium(K)fertilizer gradient on the microbial community in wheat-maize double-cropping systems remains unclear.In this long-term field experiment(2008-2019),we researched bacterial and fungal diversity,composition,and community assemblage in the soil along a K fertilizer gradient in the wheat season(K0,no K fertilizer;K1,45 kg ha^(-1) K_(2)O;K_(2),90 kg ha^(-1)K_(2)O;K3,135 kg ha^(-1)K_(2)O)and in the maize season(K0,no K fertilizer;K_(1),150 kg ha^(-1) K_(2)O;K_(2),300 kg ha^(-1)K_(2)O;K_(3),450 kg ha^(-1)K_(2)O)using bacterial 16S rRNA and fungal internally transcribed spacer(ITS)data.We observed that environmental variables,such as mean annual soil temperature(MAT)and precipitation,available K,ammonium,nitrate,and organic matter,impacted the soil bacterial and fungal communities,and their impacts varied with fertilizer treatments and crop species.Furthermore,the relative abundance of bacteria involved in soil nutrient transformation(phylum Actinobacteria and class Alphaproteobacteria)in the wheat season was significantly increased compared to the maize season,and the optimal K fertilizer dosage(K2 treatment)boosted the relative bacterial abundance of soil nutrient transformation(genus Lactobacillus)and soil denitrification(phylum Proteobacteria)bacteria in the wheat season.The abundance of the soil bacterial community promoting root growth and nutrient absorption(genus Herbaspirillum)in the maize season was improved compared to the wheat season,and the K2 treatment enhanced the bacterial abundance of soil nutrient transformation(genus MND1)and soil nitrogen cycling(genus Nitrospira)genera in the maize season.The results indicated that the bacterial and fungal communities in the double-cropping system exhibited variable sensitivities and assembly mechanisms along a K fertilizer gradient,and microhabitats explained the largest amount of the variation in crop yields,and improved wheat?maize yields by 11.2-22.6 and 9.2-23.8%with K addition,respectively.These modes are shaped contemporaneously by the different meteorological factors and soil nutrient changes in the K fertilizer gradients.
基金supported by the National Key Research and Development Programs(2021YFB3704201 and 2021YFB3700902).
文摘The industrial sector is the primary source of carbon emissions in China.In pursuit of meeting its carbon reduction targets,China aims to promote resource consumption sustainability,reduce energy consumption,and achieve carbon neutrality within its processing industries.An effective strategy to promote energy savings and carbon reduction throughout the life cycle of materials is by applying life cycle engineering technology.This strategy aims to attain an optimal solution for material performance,resource consumption,and environmental impact.In this study,five types of technologies were considered:raw material replacement,process reengineering,fuel replacement,energy recycling and reutilization,and material recycling and reutilization.The meaning,methodology,and development status of life cycle engineering technology abroad and domestically are discussed in detail.A multidimensional analysis of ecological design was conducted from the perspectives of resource and energy consumption,carbon emissions,product performance,and recycling of secondary resources in a manufacturing process.This coupled with an integrated method to analyze carbon emissions in the entire life cycle of a material process industry was applied to the nonferrous industry,as an example.The results provide effective ideas and solutions for achieving low or zero carbon emission production in the Chinese industry as recycled aluminum and primary aluminum based on advanced technologies had reduced resource consumption and emissions as compared to primary aluminum production.
基金supported by the National Natural Science Foundation of China (Nos. 21775116 and 21922411)DICP Innovation Funding (Nos. DICP-RC201801 and DICP I202008)Liao Ning Revitalization Talents Program (No. XLYC1802109)。
文摘Prion diseases are fatal neurodegenerative diseases that can cause severe dementia.The misfolding and accumulation of the prion peptide (PrP)_(106–126) is crucial,and this process is closely relevant to biological membranes.However,how PrP_(106–126)aggregation is affected by the molecular chirality of phospholipid membrane is unknown.Thus,in this study,a pair of L-and D-aspartic acid (Asp)-modified 1,2-dipalmitoyl-sn–glycero-3-phosphoethanolamine (DPPE) were synthesized to construct chiral liposomes.We discover that L-Asp-DPPE liposomes strongly inhibit the oligomerization and amyloidogenesis of PrP_(106–126),whether acting on monomers or oligomers,which rescues cytotoxicity induced by PrP_(106–126).By comparison,D-Asp-DPPE liposomes inhibit peptide oligomerization only at a high concentration and cannot prevent amyloidogenesis when acting on oligomers,which lead to pronounced cytotoxicity.Apoptosis experiment,dynamic change of intracellular Ca^(2+)(_(i)Ca^(2+)) and Ca^(2+)release from endoplasmic reticulum(ER),reactive oxygen species (ROS) production,adsorption dynamics and affinity tests,and fluorescent imaging clearly disclose that molecular chirality of the liposomes dominates conformational transition of PrP_(106–126)from random coil to β-sheet,binding and adsorption of the monomers and oligomers,and subsequent fibrillation process,resulting in distinct inhibition effect in Ca^(2+)overload and release,ROS production and cell apoptosis.This work is the first to report that interfacial molecular chirality is a potentially crucial influence on the fibrillation process of PrP_(106–126) and its cell responses,whereas the convergence of chiral amino acids and liposomes can be considered potential inhibitors in prion diseases.
基金Key R&D Program of Hebei Province:Special Project on Key Common Technologies for High-quality Agricultural Development(20327505D).
文摘[Objectives]This study was conducted to develop an enzyme-linked immunoassay kit that can detect the residual amount of pentachloronitrobenzene in Penaeus vannamei.[Methods]This study was conducted to develop an enzyme-linked immunoassay kit that can detect the residual amount of pentachloronitrobenzene in P.vannamei.[Results]The standard curve range of the kit was 0-8.1μg/L;the detection limit for P.vannamei was 0.912μg/kg;the recovery was 80.6%-103.5%;and the relative standard deviation range within batches was 5.3%-10.1%,and the relative standard deviation range between batches was 6.7%-8.1%.The specificity of the pentachloronitrobenzene monoclonal antibody was relatively good,and the cross-reaction rates with pentachlorophenol,hexachlorobenzene,tetrachlorophthalide,and chlorothalonil were low,all of which did not exceed 30%.The ELISA kit could be stored at 4℃for 12 months,showing good stability.[Conclusions]The detection kit has low cost,short time and small deviation,and is an ideal preliminary screening method.
基金supported by the funds of the Shanghai Sailing Program,the National Natural Science Foundation of China(No.52104386)the Xi’an Association for Science and Technology Young Talents Lifting Program,and the State Key Laboratory of Solidification Processing(NPU),China(No.2022-TS-08).
文摘Eutectic high-entropy alloys(EHEAs)that combine the advantages of HEAs and eutectic alloys are promising materials for high-temperature environments.However,the mechanical properties of currently developed EHEAs still cannot meet the servicing requirements.Here,we propose a strategy to optimize the tensile properties in a Al_(21)Co_(19.5)Fe_(9.5)Ni_(50)EHEA by regulating the phase transformation and precipitation features.The results showed that the as-cast Al_(21)Co_(19.5)Fe_(9.5)Ni_(50)EHEA mainly consists of face-centered cubic(FCC)and B2 phases showing a lamellar morphology,and the FCC and B2 phases keep a stable K-S orientation relationship.Solution treatment at 900 and 1100°C followed by furnace cooling to room temperature leads to a significant precipitation of L1_(2)phases within the FCC phases.In the subsequent tensile deformation process,dispersed L1_(2)phases and the transformation from B2 to L1_(0)phases can significantly enhance the yield strength of the designed EHEA.Furthermore,solution treatment at the same temperature,followed by rapid water quenching,results in the appearance of numerous L1_(0)phases within the B2 phases.The transformation from L1_(0)to B2 phases during subsequent tensile deformation can make the B2 and FCC phases return to a K-S orientation relationship.This,in turn,reduces the tendency for dislocation pile-ups at the phase interfaces and improves the ductility.We believe that this work will provide some new references for designing EHEAs with excellent mechanical properties.
基金supported by the National Natural Science Foundation of China(Nos.51971021,52203382,and 11775017)the National Magnetic Confinement Fusion Program of China(No.2019YFE03130002)the Young Talent Fund of Association for Science and Technology in Shaanxi,China(No.20230415).
文摘The TiNbV_(0.5)Ta_(0.5)Cr_(x)(x=0,0.1,0.2,0.5)refractory high-entropy alloys(RHEAs)with an excellent combination of ductility and strength were designed and prepared for high-temperature applications.The yield strength,ultimate tensile strength,and elongation of the TiNbV_(0.5)Ta_(0.5)Cr_(0.1) alloy were 878 MPa,928 MPa,and 21.6%,respectively.Important issues of microstructure evolution,precipitation process,and their impact on mechanical properties were concerned.Then,the effect of Cr content on the mechanical properties of TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys was evaluated through a quantitative analysis of the strengthening mechanism,which elucidated the trade-offrelationship between solid solution strengthening and precipitation strengthening in RHEA.The microstructure evolution of the TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys involved the formation and interconversion of titanium allotropes(α-Ti and β-Ti)and the precipitation of the Laves phase.Significant embrittlement was induced by the preferential precipitation of α-Ti on the grain boundary.The TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys exhibited an incubation period for Laves phase precipitation,which was related to the Cr content in the alloy.The Laves phase preferentially nucleated next to α-Ti due to the redistribution of elements during the α-Ti precipitation process.The precipitation of the Laves phase played an important role in enhancing the strength of the TiNbV_(0.5)Ta_(0.5)Cr_(x) alloys.
文摘The southwest mountainous area is a frequent debris flow disaster area in<span><span><span style="font-family:;" "=""><span style="font-family:Verdana;"> China, which poses a serious threat to the regional roads and greatly affects the normal traffic operation and the safety of residents’ lives and property. The debris flow risk assessment of highway can quantify the threat degree of debris flow to the roads. In this paper, from the perspective of villages and towns, taking the upper reaches of Minjiang River as the research area, four factors including road network density, highway disaster resistance capacity, population density and highway cost are selected, and the weight is obtained by using entropy weight method, and the debris flow vulnerability evaluation results of highway are obtained by weighted calculation. Four indexes of debris flow density, shape factor, relative height difference and annual rainfall are selected to evaluate the debris flow hazard of highway by using the information method. Based on the vulnerability and hazard evaluation results, the ri</span><span style="font-family:Verdana;">sk of highway debris flow is evaluated, and the results are classified and</span><span style="font-family:Verdana;"> discussed. The results show that: the risk of debris flow on the upper reaches of Minjiang River is relatively low, the overall spatial distribution shows a trend of high in the East and low in the west, and the overall risk of township roads in Wenchuan county is the highest;The risk of debris flow is generally high within </span></span></span></span><span><span><span style="font-family:;" "=""><span style="font-family:Verdana;">-10 to 30</span><span style="font-family:Verdana;"> km from the central fault zone of Longmenshan.</span></span></span></span>
