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SiO_(2)decorated wood nanocomposite with enhanced mechanical performance,flame and water resistance
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作者 Youyong Wang Xiangqian Wang +5 位作者 Beizhou Zhang Shuai Zhai Hao Li Yuanqing Li Weibin Zhu Shaoyun Fu 《Nano Materials Science》 2026年第2期307-313,共7页
Development of lightweight and strong structural material using fast-growing poplar wood is promising for green and sustainable engineering.Herein,the overall performances of fast-growing natural poplar wood(NPW)are s... Development of lightweight and strong structural material using fast-growing poplar wood is promising for green and sustainable engineering.Herein,the overall performances of fast-growing natural poplar wood(NPW)are significantly enhanced via delignification,in situ growth of SiO_(2)followed by densification.The SiO_(2)/compresseddelignified-wood(SiO_(2)/CDW)nanocomposite obtained exhibits outstanding mechanical properties including a bending strength of 395.6 MPa,a tensile strength of 253.4 MPa,and a toughness of 7.1 MJ/m^(3),which is improved by 1548%,240%and 590%,respectively compared with NPW.In addition,the ignition time and burning time of SiO_(2)/CDW nanocomposite are prolonged by 700%and 112%compared to those of NPW.Moreover,the specific wear rate of SiO_(2)/CDW is 18×10^(-6)mm^(3)/Nm,which is 72.6%lower than that of NPW.Moreover,the spring-back ratios of SiO_(2)/CDW in 95%and in water are 45.2%and 66.7%,which are lower than those of CDW(64.6%and 92.4%).The SiO_(2)/CDW nanocomposite with enhanced mechanical,flame/water retardant and wear performances are promising to meet the needs of modern engineering as green and sustainable materials. 展开更多
关键词 WOOD SiO_(2) Mechanical robustness Fire resistance Water resistance Wear resistance
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Dual carbapenem-fluoroquinolone resistance in community-onset pediatric urinary tract infections:Phenotypic-genotypic integration in three cases
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作者 C Quang Ngo D Hung Tran +2 位作者 T Trung Huynh Q Nhu Nguyen H My Le 《Asian Pacific Journal of Tropical Medicine》 2026年第1期45-48,共4页
Urinary tract infections(UTIs)are among the most prevalent pediatric bacterial infections,and undertreated episodes may lead to renal scarring,hypertension,or chronic kidney disease.Multidrug-resistant(MDR)Enterobacte... Urinary tract infections(UTIs)are among the most prevalent pediatric bacterial infections,and undertreated episodes may lead to renal scarring,hypertension,or chronic kidney disease.Multidrug-resistant(MDR)Enterobacterales have been increasingly reported in children,with higher rates in Asian and Middle Eastern settings than in high-income countries[1,2]. 展开更多
关键词 phenotypic genotypic integration chronic kidney diseasemultidrug resistant mdr enterobacterales community onset pediatric urinary tract infections renal scarring urinary tract infections dual carbapenem fluoroquinolone resistance multidrug resistant enterobacterales
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Molecular nonchemically amplified resists based on spirobixanthene backbone:Sulfoxime oxime esters versus sulfonium salts
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作者 Yu Yan Chenfei Zhao +5 位作者 Jingwen Hui Xinfu Zhang Xue Zhang Pengzhong Chen Xiaojun Peng Yi Xiao 《Smart Molecules》 2026年第1期127-133,共7页
The nonchemically amplified(nonCA)polymer resists,including ionic and nonionic types,have achieved higher resolution and smaller line edge roughness(LER)than traditional chemically amplified ones.However,for polymer r... The nonchemically amplified(nonCA)polymer resists,including ionic and nonionic types,have achieved higher resolution and smaller line edge roughness(LER)than traditional chemically amplified ones.However,for polymer resists,chain entanglement is an inevitable limitation for the further reduction of LER.To overcome this problem,it is logical to apply the nonCA concept to molecule-based resists due to their advantages of monodispersity and small size.To date,only a few examples of ionic sulfonium salts-based nonCA molecular glass resists(nonCAMGRs)have been reported.They demonstrated high resolution and small LER well,but their electron beam sensitivity seemed less than ideal.To our knowledge,non-ionic sulfoxime oxime esters-based molecular resists were not reported yet,which leaves room for new round of more in-depth reserch on nonCAMGRs.Here,employing the excellent spirobixanthene backbone,we have first designed non-ionic sulfoxime oxime esters-based nonCAMGRs X4-NI-tf and X4-NI-tfb,for comparison,sulfonium salts-based nonCAMGRs X4-I-otfdm was designed.All exhibit favorable thermal properties(T_(d,5%)>200°C)and filmforming capabilities(RMSs<0.4 nm).Via EBL,X4-I-otfdm achieved higher resolution(16 nm,LER 1.4 nm)than X4-NI-tf and X4-NI-tfb(20 nm,LER 1.6 nm).But contrast curve revealed that the sensitivity of X4-NI-tf and X4-NI-tfb(D_(100):370 and 350μC/cm^(2))was significantly higher than X4-I-otfdm(D_(100):3300μC/cm^(2)),demonstrating that the sensitivity of sulfoxime oxime esters exceeds that of sulfonium salts and introduction of bromine can further enhance the sensitivity;based on above,X4-NI-tfb exhibited the lowest Z-factor and demonstrated the best overall performance.We believe that nonCAMGRs based on sulfoxime oxime esters represent a strong candidate for high-performance photoresists. 展开更多
关键词 e-beam lithography molecular glass resist nonchemically amplified resist PHOTOresist spirobixanthene
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Trends in Antibiotic Consumption and Antimicrobial Resistance in China:An Ecological Analysis from 2016 to 2022
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作者 Fei Zhao Zinan Zhao +13 位作者 Di Chen Bolin Zhu Tianqi Zhang Yuanchao Zhu Xuelin Sun Liang Liang Nan Zheng Lili Zou Wenfeng Xu Sirui Guo Yue Wang Ming Zhao Xin Hu Pengfei Jin 《Biomedical and Environmental Sciences》 2026年第2期158-170,共13页
Objective To examine national trends in antibiotic consumption and antimicrobial resistance(AMR)among six WHO-priority bacterial pathogens in China from 2016 to 2022.Methods This ecological study analyzed national and... Objective To examine national trends in antibiotic consumption and antimicrobial resistance(AMR)among six WHO-priority bacterial pathogens in China from 2016 to 2022.Methods This ecological study analyzed national and provincial data from the China Antibacterial Resistance Surveillance System(CARSS)and the National Hospital Information Network.Beta regression models assessed temporal trends,and hierarchical models evaluated associations between antibiotic use and resistance.Results From 2016 to 2022,carbapenem resistance in Acinetobacter baumannii and Pseudomonas aeruginosa,and vancomycin resistance in Enterococcus faecium and E.faecalis significantly declined(β<0,P<0.010),while carbapenem-resistant Klebsiella pneumoniae increased(β=0.081,P<0.001).Nationwide antibiotic consumption rose across 10 major classes.Positive associations were found between carbapenem use and resistance in A.baumannii(z=2.719,P=0.007)and P.aeruginosa(z=3.241,P=0.001),and between vancomycin use and resistance in E.faecium(z=4.510,P=0.001)and E.faecalis(z=3.210,P=0.001).Conclusion Carbapenem-resistant K.pneumoniae increased significantly in China,while other resistant pathogens declined.Resistance patterns were linked to the use of multiple antibiotic classes,underscoring the need for strengthened antibiotic stewardship and surveillance. 展开更多
关键词 Antimicrobial resistance Carbapenem-resistant microorganisms Vancomycin-resistant enterococci Antibiotic consumption
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Fitness and resistance mechanism of Fusarium pseudograminearum mutants resistant to fludioxonil
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作者 TIAN Yingming CHEN Yawei +3 位作者 DUAN Xiaoxin ZHENG Wei XU Jianqiang HOU Ying 《农药学学报》 北大核心 2026年第2期277-291,244,共16页
Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide... Fusarium crown rot(FCR),predominantly caused by Fusarium pseudograminearum,has been listed as a Category Ⅱ disease in six provinces of China,posing a significant threat to wheat production.The phenylpyrrole fungicide fludioxonil is a key agent for FCR control.Previous studies indicated that resistance to fludioxonil in F.pseudograminearum is primarily associated with altered expression levels of the FpOS1 gene,which encodes a hybrid histidine kinase.However,the roles of mutations in other FpOS genes and the molecular interactions between FpOS proteins and fludioxonil remain elusive.To address these gaps,we generated 16 fludioxonil-resistant mutants with heritable resistance traits by in vitro selection of four sensitive F.pseudograminearum isolates.These mutants exhibited high resistance levels,with resistance factors(RF)ranging from 633.73 to 8617.07.Compared to their parental isolates,the resistant mutants showed significantly reduced mycelial growth rate,sporulation capacity,and pathogenicity.They were also more sensitive to ionic,osmotic,and oxidative stresses and displayed compromised cell wall and membrane integrity.Fludioxonil demonstrated no cross-resistance with tebuconazole or pydiflumetofen;however,it exhibited weak positive crossresistance to pyraclostrobin and moderate positive cross-resistance to iprodione.Fludioxonil treatment significantly promoted glycerol synthesis and inhibited deoxynivalenol(DON)production in parental isolates,whereas these regulatory effects were markedly attenuated in the resistant mutants.Mutation analysis identified mutation sites in FpOS1,FpOS4,and FpOS5 genes,with a lower mutation frequency in FpOS1 and no mutations detected in FpOS2.Molecular docking indicated that amino acid substitutions in FpOS4 and FpOS5 significantly reduced the binding affinity of fludioxonil to these target proteins.In conclusion,F.pseudograminearum poses a moderate risk of resistance to fludioxonil.Point mutations in FpOS4 and FpOS5 genes emerge as key molecular drivers of resistance,likely by diminishing the binding affinity between the fungicide and its proteins.This study clarifies the molecular basis of fludioxonil resistance in F.pseudograminearum and provides a scientific rationale for the judicious use of this fungicide in managing FCR. 展开更多
关键词 Fusarium pseudograminearum fludioxonil resistant mutant survival fitness resistant mechanism
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Enhancement of the crack and erosion resistance of silty clay under freeze–thaw cycles:Synergistic effect of sisal fiber–fly ash
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作者 DING Jiashun LIU Huanan +4 位作者 QIU Dan ZHAI Lianghao QI Bo YU Chenglong YUE Keyu 《Journal of Mountain Science》 2026年第2期828-844,共17页
Freeze–thaw(F–T)cycle-induced cracking in silty clays poses a significant risk to engineering stability.Although the individual addition of fly ash(FA)or sisal fiber(SF)provides partial solutions,their simultaneous ... Freeze–thaw(F–T)cycle-induced cracking in silty clays poses a significant risk to engineering stability.Although the individual addition of fly ash(FA)or sisal fiber(SF)provides partial solutions,their simultaneous application may result in a synergistic effect to compensate for their respective shortcomings.In this study,the effects of SF and FA on the mechanical properties,crack resistance,water retention,and erosion resistance of improved soil were systematically investigated through unconfined compressive strength(UCS)tests,crack evolution analysis,simulated rainfall erosion tests,and microscopic characterization(laser particle size analysis and nitrogen adsorption).The results reveal that the volumetric stability of FA particles significantly inhibits cracking in soil after F–T cycles.However,FA contributes only slightly to soil strength and erosion resistance.SF,on the other hand,plays a substantial role in increasing both soil strength and erosion resistance.The synergy between FA and SF results in the simultaneous increase in crack resistance,erosion resistance,and strength.FA improves the aggregate stability during F–T cycles,whereas SF reinforces the bonds between these aggregates.A comprehensive evaluation of the improved soil during F–T cycles using the entropy weight-TOPSIS method reveal that the combination of 10%FA+18 mm SF performed the best,achieving a 246%higher composite score than the unmodified soil did.With respect to this optimal combination,compared with the unmodified soil,the SF–FA-improved soil exhibits a 30%reduction in the average crack width,a 30%reduction in the erosion rate,and a 46%increase in strength.The findings of this study provide a scientific basis for the design of soil improvement in disaster mitigation engineering in seasonally frozen soil regions. 展开更多
关键词 Freeze-thaw cycle Sisal fiber Fly ash Crack resistance Erosion resistance Synergistic effect
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How do nanomaterials influence the spread of antibiotic resistance genes in aquatic environments?
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作者 Yun Bai Shengnan Li Shih-Hsin Ho 《Chinese Chemical Letters》 2026年第1期186-197,共12页
Antibiotic resistance genes(ARGs) are recognized as a primary threat to the sustainability of environment and human health in the 21^(st) century.Nanomaterials(NMs) have attracted substantial attention due to their un... Antibiotic resistance genes(ARGs) are recognized as a primary threat to the sustainability of environment and human health in the 21^(st) century.Nanomaterials(NMs) have attracted substantial attention due to their unique dimensions and structures.Unfortunately,emerging evidence suggests that NMs may facilitate the transmission of ARGs.It is crucial to elucidate how NMs affect the evolution and dissemination of ARGs.The current review comprehensively examines the role of NMs in the widespread transmission of ARGs in aquatic environments and the underlying mechanisms involved in the process.It aims to clarify the effects and mechanisms of NMs on the horizontal gene transfer processes that are associated with ARGs,including the enhancement of cell membrane permeability,the formation of nanopores on membranes,promotion of mutagenesis,and the generation of reactive oxygen species(ROSs).Furthermore,the trade-off between the removal of ARGs and horizontal transfer has been elucidated.The review aspires to guide future research directions,advance knowledge on the implications of NMs in the field of ARGs' transmission,and provide a theoretical foundation for the development of safer and more effective applications of NMs. 展开更多
关键词 Antibiotic resistance genes Antibiotic resistance bacteria NANOMATERIALS Horizontal gene transfer Aquatic environments
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QTL-Seq Identifies Genomic Regions Associated with Resistance to Bipolaris oryzae and Their Association with Defense Related Enzyme Activity in Rice
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作者 Jagjeet Singh LORE Sanjay KUMAR +4 位作者 Dharminder BHATIA Mandeep Singh HUNJAN Rishabh MAHESHWARI Dayananda Veeriah Patil Jyoti JAIN 《Rice science》 2026年第1期15-20,I0028-I0033,共12页
Brown spot(BS)of rice,caused by Bipolaris oryzae,is a serious concern that not only causes quantitative losses but also affects grain quality.To manage this disease,the use of resistant genetic sources and QTLs is an ... Brown spot(BS)of rice,caused by Bipolaris oryzae,is a serious concern that not only causes quantitative losses but also affects grain quality.To manage this disease,the use of resistant genetic sources and QTLs is an eco-friendly and economical option.In the current study,F_(3) progenies derived from a cross of susceptible parent PMS-18-B(PAU 10845-1-1-1-1)×resistant parent RP Path 77(RP patho-17)were used to identify potential QTLs linked to BS resistance and to associate this resistance with a temporal spike in defense-related enzymes. 展开更多
关键词 bipolaris oryzae temporal spik resistANCE defense related enzymes bipolaris oryzaeis identify potential qtls resistant genetic sources quantitative trait loci
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Enhancement in erosion resistance of Al_(2)O_(3)-SiC-C refractories for high scrap steel ratio ladles:role of MgAl_(2)O_(4) spinel
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作者 Chen Hu Cheng-Ji Deng +4 位作者 Chao Yu Jun Ding Zheng-Long Liu Jin-Tao Wang Bei-Yue Ma 《Journal of Iron and Steel Research International》 2026年第1期100-109,共10页
To resolve severe slag penetration and erosion in Al_(2)O_(3)-SiC-C refractories during high scrap ratio iron ladle operation,a novel strategy utilizing exogenous MgAl_(2)O_(4) spinel as a sacrificial FeO_(x) scavenge... To resolve severe slag penetration and erosion in Al_(2)O_(3)-SiC-C refractories during high scrap ratio iron ladle operation,a novel strategy utilizing exogenous MgAl_(2)O_(4) spinel as a sacrificial FeO_(x) scavenger was proposed.Al_(2)O_(3)-SiC-C refractories produced with plate-like corundum,silicon carbide,and flake graphite incorporating MgAl_(2)O_(4) additives were cured at 1400℃ in the condition of carbon embedding.The impacts of additives on phase composition,microscopic morphology,and performance of materials were studied.The results indicated that Al_(2)O_(3)-SiC-C refractories with the addition of 2 wt.%MgAl_(2)O_(4) exhibited a smaller oxidation area after oxidation tests compared to samples without MgAl_(2)O_(4),resulting in 28%improvement in oxidation resistance compared to blank samples.In the erosion test,the results informed that adding 4 wt.%MgAl_(2)O_(4) induced significant interfacial slag modification:MgAl_(2)O_(4) dynamically dissolved FeO_(x) to form protective Mg(Fe,Al)_(2)O_(4) solid solution on the slag-refractory interface.This sacrificial dissolution effectively immobilized FeO_(x),elevated local slag viscosity,and fundamentally inhibited slag penetration and matrix dissolution.The erosion index decreased from 50%in the blank group to 27.4%. 展开更多
关键词 Al_(2)O_(3)-SiC-C refractory MgAl_(2)O_(4)spinel Erosion resistance Oxidation resistance High scrap ratio
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Neuroendocrine prostate cancer(NEPC)-associated centrosomal Protein 55(CEP55)promotes cisplatin resistance in prostate cancer by regulating cyclin-dependent kinase 1(CDK1)phosphorylation
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作者 Zhuocheng Lai Chenxi Hu +9 位作者 Jirong Jie Yongyuan Xiao Yuanchao Zhu Xueni Guo Yintong Liu Yiwei Wang Shiyu Pang Xiangbo Zeng Wanlong Tan Qiong Wang 《Cancer Pathogenesis and Therapy》 2026年第1期51-63,共13页
Background Neuroendocrine prostate cancer(NEPC)is an aggressive subtype of castration-resistant prostate cancer(CRPC)that is typically resistant to nearly all current therapies.Methods In this study,single-cell RNA se... Background Neuroendocrine prostate cancer(NEPC)is an aggressive subtype of castration-resistant prostate cancer(CRPC)that is typically resistant to nearly all current therapies.Methods In this study,single-cell RNA sequencing(scRNA-seq)and bioinformatic analysis identified centrosomal protein 55(CEP55)as a critical factor in the transformation from hormone-sensitive prostate cancer(HSPC)to CRPC and,ultimately to,NEPC.Results Subsequent bioinformatics analyses and clinical sample validation showed that CEP55 is significantly upregulated in NEPC tissues relative to HSPC and CRPC.Furthermore,while CEP55 show no significant association with the immune microenvironment or cancer-associated fibroblasts(CAFs),our findings indicated that it directly mediates the plasticity of prostate cancer cells,thereby driving NEPC progression.Specifically,in vivo and in vitro experiments confirmed that CEP55 enhances cell proliferation,migration,invasion and the expression of NEPC biomarkers in prostate cancer.Importantly,although cisplatin is the primary treatment for NEPC clinically,CEP55 has been shown to regulate cisplatin resistance through the phosphorylation of cyclin-dependent kinase 1(CDK1)at the tyrosine 15(Tyr15)site.Conclusions In summary,our study identifies a key gene that influences the neuroendocrine differentiation process in prostate cancer,suggesting its potential as an important therapeutic target. 展开更多
关键词 Prostate cancer Castration-resistant prostate cancer Neuroendocrine prostate cancer Cisplatin resistance CEP55
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Brain insulin resistance and neuropsychiatric symptoms in Alzheimer's disease:A role for dopamine signaling
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作者 Anastasia Kontogianni Hongbin Yang Wenqiang Chen 《Neural Regeneration Research》 2026年第5期1995-1996,共2页
Type 2 diabetes mellitus has central complications:Diabetes,a metabolic disorder primarily characterized by hyperglycemia due to insufficient insulin secretion,or impaired insulin signaling,has significant central com... Type 2 diabetes mellitus has central complications:Diabetes,a metabolic disorder primarily characterized by hyperglycemia due to insufficient insulin secretion,or impaired insulin signaling,has significant central complications.Type 2 diabetes mellitus(T2DM),the most prevalent type of diabetes,affects more than 38 million individuals in the United States(approximately 1 in 10)and is defined by chronic hyperglycemia and insulin resistance,which refers to a reduced cellular response to insulin. 展开更多
关键词 reduced cellular response insulin dopamine signaling insulin resistancewhich metabolic disorder type diabetes mellitus brain insulin resistance Alzheimers disease neuropsychiatric symptoms
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Machine learning-based investigation of uplift resistance in special-shaped shield tunnels using numerical finite element modeling 被引量:1
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作者 ZHANG Wengang YE Wenyu +2 位作者 SUN Weixin LIU Zhicheng LI Zhengchuan 《土木与环境工程学报(中英文)》 北大核心 2026年第1期1-13,共13页
The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combi... The uplift resistance of the soil overlying shield tunnels significantly impacts their anti-floating stability.However,research on uplift resistance concerning special-shaped shield tunnels is limited.This study combines numerical simulation with machine learning techniques to explore this issue.It presents a summary of special-shaped tunnel geometries and introduces a shape coefficient.Through the finite element software,Plaxis3D,the study simulates six key parameters—shape coefficient,burial depth ratio,tunnel’s longest horizontal length,internal friction angle,cohesion,and soil submerged bulk density—that impact uplift resistance across different conditions.Employing XGBoost and ANN methods,the feature importance of each parameter was analyzed based on the numerical simulation results.The findings demonstrate that a tunnel shape more closely resembling a circle leads to reduced uplift resistance in the overlying soil,whereas other parameters exhibit the contrary effects.Furthermore,the study reveals a diminishing trend in the feature importance of buried depth ratio,internal friction angle,tunnel longest horizontal length,cohesion,soil submerged bulk density,and shape coefficient in influencing uplift resistance. 展开更多
关键词 special-shaped tunnel shield tunnel uplift resistance numerical simulation machine learning
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Developing eco-friendly,pest-resistant cotton by a heterologous multi-gene transformation system for caffeine synthesis 被引量:2
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作者 Yibo Fan Yingchao Tang +11 位作者 Yuanmei Miao Yanchang Zhao Lu Yu Peng Han Xiangqian Zhu Tingwan Li Guanying Wang Zhongping Xu Lu Long Wei Gao Lisong Hu Shuangxia Jin 《The Crop Journal》 2026年第1期166-175,共10页
Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a n... Cotton production faces significant challenges from insect pests,with chemical pesticide use becoming increasingly limited by resistance and environmental concerns.This study explores the potential use of caffeine,a natural plant alkaloid,as an environmentally friendly insect resistance strategy in cotton.Exogenous caffeine application demonstrated potent insecticidal effects against cotton bollworm(Helicoverpa armigera)larvae,with concentrations≥2 mg mL−1 causing near-complete feeding cessation and up to 70%larval mortality.Building on this,we engineered transgenic cotton(Gossypium hirsutum cv.Jin668)for heterologous caffeine biosynthesis by introducing three key N-methyltransferase genes(CaXMT1,CaMXMT1,CaDXMT1)by multiple gene transformation.Transgenic lines expressing all three genes showed remarkable caffeine accumulation(up to 3.59 mg g−1 dry weight),whereas two-gene combinations exhibited wild-type-level production.Feeding preference assays revealed that caffeine-enriched cotton strongly deterred feeding by H.armigera.Non-choice feeding trials demonstrated reduced leaf consumption and reduced larval growth in H.armigera fed on caffeine-producing cotton.The study highlights the effectiveness of synthetic biology approaches using the TGSII-UNiE multigene stacking system,despite challenges in transgene stability.This work advances plant-derived insect resistance research and provides a sustainable framework for reducing chemical pesticide reliance in cotton production,while underscoring unique potential of cotton as a synthetic biology platform for secondary metabolite engineering. 展开更多
关键词 Synthetic biology ALKALOIDS Pest resistance BIOPESTICIDE Secondary metabolite
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Inverse design framework of hybrid honeycomb structure with high impact resistance based on active learning 被引量:1
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作者 Xingyu Shen Ke Yan +5 位作者 Difeng Zhu Hao Wu Shijun Luo Shaobo Qi Mengqi Yuan Xinming Qian 《Defence Technology(防务技术)》 2026年第1期407-421,共15页
In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honey... In this study,an inverse design framework was established to find lightweight honeycomb structures(HCSs)with high impact resistance.The hybrid HCS,composed of re-entrant(RE)and elliptical annular re-entrant(EARE)honeycomb cells,was created by constructing arrangement matrices to achieve structural lightweight.The machine learning(ML)framework consisted of a neural network(NN)forward regression model for predicting impact resistance and a multi-objective optimization algorithm for generating high-performance designs.The surrogate of the local design space was initially realized by establishing the NN in the small sample dataset,and the active learning strategy was used to continuously extended the local optimal design until the model converged in the global space.The results indicated that the active learning strategy significantly improved the inference capability of the NN model in unknown design domains.By guiding the iteration direction of the optimization algorithm,lightweight designs with high impact resistance were identified.The energy absorption capacity of the optimal design reached 94.98%of the EARE honeycomb,while the initial peak stress and mass decreased by 28.85%and 19.91%,respectively.Furthermore,Shapley Additive Explanations(SHAP)for global explanation of the NN indicated a strong correlation between the arrangement mode of HCS and its impact resistance.By reducing the stiffness of the cells at the top boundary of the structure,the initial impact damage sustained by the structure can be significantly improved.Overall,this study proposed a general lightweight design method for array structures under impact loads,which is beneficial for the widespread application of honeycomb-based protective structures. 展开更多
关键词 Re-entrant honeycomb Hybrid structures Inverse design Impact resistance LIGHTWEIGHT
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High Temperature Resistant Calcium-doped Silica Aerogels with Enhanced Thermal Insulation via Sol-Gel Hydrothermal Route
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作者 LI Hao QI Yuan +2 位作者 GAO Xiangdong ZHANG Xingxing WANG Jinmin 《无机材料学报》 北大核心 2026年第2期262-272,I0011,共12页
Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates sign... Silica aerogel has broad applications in the field of high-temperature thermal insulation due to its low density,low thermal conductivity and high stability.However,its thermal insulation performance deteriorates significantly at elevated temperatures exceeding 600℃,primarily due to the collapse of pore structure.Meanwhile,the shielding capacity of SiO_(2) aerogel to the infrared radiation at high temperature is rather low due to the intrinsic properties of SiO_(2).Herein,a strategy for improving the high-temperature stability and infrared shielding properties of SiO_(2) aerogel via Ca doping was explored.Calcium-doped silica aerogel(CSA)powders were prepared by Sol-Gel,hydrothermal,and ambient pressure drying(APD)techniques using water glass and anhydrous calcium chloride as precursors and trimethylchlorosilane as a hydrophobic modifier.The effects of Ca/Si molar ratio in the precursor and hydrothermal conditions(temperature and pH)on the crystalline properties,microscopic morphology and pore structure of CSAs were investigated.The results show that the Ca/Si molar ratio and hydrothermal treatment have significant effects on the microstructure and heat resistance of CSAs in the temperature range of 400-1000℃.The samples sintered at 1000℃have a high specific surface area of 100.1 m^(2)/g and a pore volume of 0.8705 cm^(3)/g,indicating that the CSA has good heat resistance.One-side insulation tests at temperatures up to 600℃show that the sample with a Ca/Si molar ratio of 1.0 has the best insulation performance,with a cold surface temperature of 450℃,which is 27℃lower than that of the pure silica aerogel. 展开更多
关键词 silica aerogel calcium doping high-temperature resistance HYDROTHERMAL ambient pressure drying
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High resistance SO_(2) adsorbent of Fe-Ce-La oxides@Si-Al carrier for arsenic capture from middle-low-temperature flue gas
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作者 WEN Hangyu HOU Shuyang +2 位作者 WANG Kai ZHANG Kaihua ZHANG Kai Beijing 《燃料化学学报(中英文)》 北大核心 2026年第2期166-179,共14页
It is crucial to develop arsenic removal adsorbents with strong sulfur resistance under middle-low-temperature flue gas conditions(<400℃).In this work,five Fe-Ce-La oxides were prepared by co-precipitation method,... It is crucial to develop arsenic removal adsorbents with strong sulfur resistance under middle-low-temperature flue gas conditions(<400℃).In this work,five Fe-Ce-La oxides were prepared by co-precipitation method,and FeCeLaO/SiO_(2)-Al_(2)O_(3) composite adsorbents were prepared by coupling fly ash-based Si-Al carriers.The active components Fe-Ce-La oxides and Si-Al carriers were characterized by TPD,TG,XRF,BET and XPS,respectively.The effects of temperature,Si/Al ratio and FeCeLaO loading rate on the sulfur resistance were investigated.Results show that the SO_(2) promotes the arsenic removal of Fe_(2)O_(3),CeLaO and FeCeLaO.At 400℃,the arsenic removal efficiencies of the three oxides increase from 45.3%,72.5% and 81.3% without SO_(2) to 62.6%,80.5%and 91.0%,respectively.The SO_(2) inhibits the arsenic removal of La_(2)O_(2)CO_(3) and FeLaO,and the inhibition effect is pronounced at high temperatures.The sulfur poisoning resistance of Si-Al carriers increases with the increase of Si/Al ratio.When the Si/Al ratio is increased to 9.74,the arsenic removal efficiency in the SO_(2) environment is 13.9% higher than that in the absence of SO_(2).Introducing FeCeLaO active components is beneficial for enhancing the SO_(2) poisoning resistance of Si-Al carriers.The strong sulfur resistance of the FeCeLaO/SiO_(2)-Al_(2)O_(3) composite adsorbent results from multiple factors:protective effects of Ce on Fe,La and Al;sulfation-induced generation of Ce^(3+)and surface-adsorbed oxygen;and strong surface acidity of SiO_(2). 展开更多
关键词 arsenic removal sulfur resistance flue gas Fe-Ce-La oxides fly ash
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Research Status and Prospects of Platinum Group Metal Coatings with High-Temperature Oxidation Resistance
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作者 Ding Chenxi Liu Zhongyu +3 位作者 Fang Zhen Wang Haoxu Lv Biao Hu Zhenfeng 《稀有金属材料与工程》 北大核心 2026年第2期333-344,共12页
Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materi... Platinum group metals have high melting points,strong corrosion resistance,stable chemical properties,and low oxygen permeability in high-temperature oxygen-containing environments.As thermal protective coating materials,they have gained essential applications in the aerospace field and have excellent prospects for application in frontier military fields,such as protecting hot-end components of hypersonic aircraft.This research reviewed the latest research progress of platinum group metal coatings with hightemperature oxidation resistance,including coating preparation techniques,oxidation failure,and alloying modification.The leading preparation techniques of current platinum group metal coatings were discussed,as well as the advantages and disadvantages of various existing preparation techniques.Besides,the intrinsic properties,failure forms,and failure mechanisms of coatings of single platinum group metal in high-temperature oxygen-containing environments were analyzed.On this basis,the necessity,main methods,and main achievements of alloying modification of platinum group metals were summarized.Finally,the future development of platinum group coatings with high-temperature oxidation resistance was discussed and prospected. 展开更多
关键词 platinum group metal coatings preparation technique high temperature oxidation resistance alloying modification
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In-Flight Heating Process of Cerium Oxide Powders in Radio Frequency Thermal Plasma Considering Thermal Resistance Effect
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作者 Su Yi Liu Ruizhe +3 位作者 Ahmad Hilal Zhao Peng Jin Xingyue Zhu Hailong 《稀有金属材料与工程》 北大核心 2026年第3期581-594,共14页
The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF... The in-flight heating process of cerium dioxide(CeO_(2))powders was investigated through experiments and numerical simulations.In the experiment,CeO_(2)powder(average size of 30μm)was injected into radio-frequency(RF)argon plasma,and the temperatures were measured using a DPV-2000 monitor.A model combining the electromagnetism,thermal flow,and heat transfer characteristics of powder during in-flight heating in argon plasma was proposed.The melting processes of CeO_(2)powders of different diameters,with and without thermal resistance effect,were investigated.Results show that the heating process of CeO_(2)powder particles consists of three main stages,one of which is relevant to a dimensionless parameter known as the Biot number.When the Biot value≥0.1,thermal resistance increases significantly,especially for the larger powders.The predicted temperature of the particles at the outlet(1800–2880 K)is in good agreement with the experimental result. 展开更多
关键词 RF thermal plasma thermal resistance effect heating process Biot number
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Silence of five Fusarium graminearum genes in wheat host confers resistance to Fusarium head blight
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作者 Jie Shuai Qiang Tu +9 位作者 Yicong Zhang Xiaobo Xia Yuhua Wang Shulin Cao Yifan Dong Xinli Zhou Xu Zhang Zhengguang Zhang Yi He Gang Li 《Journal of Integrative Agriculture》 2026年第3期1051-1063,共13页
Fusarium head blight(FHB),mainly caused by fungus Fusarium graminearum,is a devastating wheat disease worldwide,leading to reduced yield production and compromised grain quality due to contamination by mycotoxins,such... Fusarium head blight(FHB),mainly caused by fungus Fusarium graminearum,is a devastating wheat disease worldwide,leading to reduced yield production and compromised grain quality due to contamination by mycotoxins,such as deoxynivalenol(DON).Manipulating the specific gene expression in microorganisms through RNA interference(RNAi)presents an opportunity for new-generation double-stranded RNA(dsRNA)-based formulations to combat a large number of plant diseases.Here,we applied both spray-induced gene silencing(SIGS)and host-induced gene silencing(HIGS)to target five virulence-related and DON-synthesized genes in F.graminearum,including protein kinase gene Gpmk1,zinc finger protein gene Fg Chy1,transcription factor Fg SR,DON synthesis gene TRI5 and the cell-end marker protein gene Fg Tea A,aiming to effectively control FHB in wheat.Direct spraying of individual or combined small interfering RNA(siRNAs)from the fungus showed reduced expression of target genes and suppressed pathogenic symptoms during F.graminearum infection in wheat leaves,with the combination of all five siRNAs demonstrating superior resistance.Furthermore,we generated transgenic wheat lines expressing chimeric RNAi cassettes targeting these five genes,and two independent lines exhibited strong resistance to FHB and Fusarium crown rot,and the reduced DON accumulation.Notably,the HIGS transgenic lines did not adversely impact plant growth and yield traits.Collectively,our findings support that SIGS and HIGS represent effective strategies targeting key pathogenic genes for bolstering disease resistance in crops. 展开更多
关键词 Fusarium graminearum FHB resistance HIGS SIGS gene expression WHEAT
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Mitigating acid rain effects on stabilized soils:the role of phosphogypsum in leaching resistance
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作者 Xia Bian Jianyu Xiao +1 位作者 Tao Zhang Lingling Zeng 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第3期2300-2313,共14页
Phosphogypsum,an industrial solid waste,is an effective binder for partially replacing cement in stabilizing dredged sediments.Acid rain,as a worldwide ecological problem,also affects the long-term stability and susta... Phosphogypsum,an industrial solid waste,is an effective binder for partially replacing cement in stabilizing dredged sediments.Acid rain,as a worldwide ecological problem,also affects the long-term stability and sustainability of geotechnical materials and structures.However,the research on leaching effects and long-term durability of phosphogypsum-stabilized soils under acid rain conditions is limited and remains a significant challenge for practical applications.This study investigates the leaching effects and long-term durability of phosphogypsum-stabilized soils by simulating acid rain erosion through semi-dynamic leaching tests.Key parameters,including leached Ca^(2+)concentration,leachate pH,and unconfined compressive strength after leaching,were evaluated.Microscopic analyses with X-ray diffraction(XRD)and scanning electron microscopy(SEM)were also conducted to explore the underlying mechanisms.The results indicate that the presence of phosphogypsum in stabilized soil with high water content shows a significant improvement in leaching resistance subjected to acid ions,evidencing a lower Ca^(2+)concentration and pH value in the leachate,and a higher strength after leaching compared to those samples without phosphogypsum.SEM images and XRD analysis revealed that samples with higher phosphogypsum content possess denser structures due to more needle-shaped ettringite and other minerals in the soil matrix,contributing to improved strength and leaching resistance.The enhanced strength and leaching resistance of phosphogypsum-stabilized soil can be attributed to additional gel formation,a rise in swelling potential,ettringite bridging,and a denser microstructure,which reduces Ca^(2+)availability for leaching in acidic environments. 展开更多
关键词 LEACHING PHOSPHOGYPSUM Stabilized sediment Microscopic characteristics Leaching resistance
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