Epoxy resin is widely used in electronic packaging due to its exceptional performance,particularly the low-temperature curable thiol/epoxy system,which effectively minimizes thermal damage to sensitive electronic comp...Epoxy resin is widely used in electronic packaging due to its exceptional performance,particularly the low-temperature curable thiol/epoxy system,which effectively minimizes thermal damage to sensitive electronic components.However,the majority of commercial thiol curing agents contain hydrolysable ester bonds and lack rigid structures,which induces most of thiol/epoxy systems still suffering from unsatisfactory heat resistance and hygrothermal resistance,significantly hindering their application in electronic packaging.In this study,we synthesized a tetrafunctional thiol compound,bis[3-(3-sulfanylpropyl)-4-(3-sulfanylpropoxy)phenyl]sulfone(TMBPS)with rigid and ester-free structures to replace traditional commercial thiol curing agents,pentaerythritol tetra(3-mercaptopropionate)(PETMP).Compared to the PETMP/epoxy system,the TMBPS/epoxy system exhibited superior comprehensive properties.The rigid structures of bisphenol S-type tetrathiol enhanced the heat resistance and mechanical properties of TMBPS/epoxy resin cured products,outperforming those of PETMP/epoxy resin cured products.Notably,the glass transition temperature of TMBPS/epoxy resin cured products was 74.2℃which was 11.8°C higher than that of PETMP cured products.Moreover,the ester-free structure in TMBPS contributed to its enhanced resistance to chemicals and hygrothermal conditions.After undergoing 1000 h of hightemperature and high-humidity aging,the tensile strength and adhesion strength of TMBPS-cured products were 73.33 MPa and 3.39 MPa,respectively exceeding 100%and 40%of their initial values,while PETMP-cured products exhibited a complete loss of both tensile strength and adhesion strength.This study provides a strategy for obtaining thermosetting polymers that can be cured at low temperatures and exhibit excellent comprehensive properties.展开更多
To improve the high-temperature service properties of coppery tuyere,Co06 coating with a Ni60A interlayer was prepared on copper by plasma cladding.Ni60A interlayer acted as a bridge to promote the element diffusion,t...To improve the high-temperature service properties of coppery tuyere,Co06 coating with a Ni60A interlayer was prepared on copper by plasma cladding.Ni60A interlayer acted as a bridge to promote the element diffusion,thus achieving metallurgical bonding.Due to the strengthening effect ofγ-Co,Cr_(23)C_(6)and Cr_(7)C_(3)phases,the wear resistance of Co06–Ni60A coating was much higher than that of copper substrate.As the temperature increased,the wear resistance of coating decreased first and then increased.The coating exhibited better wear resistance at 600℃ due to the oxidation wear mechanism.Compared with copper substrate and Ni60A,the oxidation resistance of Co06 was increased by 6.0 and 1.9 times,respectively.For melting loss resistance,Co06–Ni60A coating was superior to Ni60A single-layer coating,but the molten iron can still form a micro-metallurgical bonding with the coating surface.展开更多
Type 2 diabetes mellitus and Parkinson's disease are chronic diseases linked to a growing pandemic that affects older adults and causes significant socio-economic burden.Epidemiological data supporting a close rel...Type 2 diabetes mellitus and Parkinson's disease are chronic diseases linked to a growing pandemic that affects older adults and causes significant socio-economic burden.Epidemiological data supporting a close relationship between these two aging-related diseases have resulted in the investigation of shared pathophysiological molecular mechanisms.Impaired insulin signaling in the brain has gained increasing attention during the last decade and has been suggested to contribute to the development of Parkinson's disease through the dysregulation of several pathological processes.The contribution of type 2 diabetes mellitus and insulin resistance in neurodegeneration in Parkinson's disease,with emphasis on brain insulin resistance,is extensively discussed in this article and new therapeutic strategies targeting this pathological link are presented and reviewed.展开更多
Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,a...Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.展开更多
Plutella xylostella,a major pest of cruciferous vegetables worldwide,has developed resistance to diamide insecticides.Thiotraniliprole,a novel synthetic diamide insecticide,exhibits excellent activity against P.xylost...Plutella xylostella,a major pest of cruciferous vegetables worldwide,has developed resistance to diamide insecticides.Thiotraniliprole,a novel synthetic diamide insecticide,exhibits excellent activity against P.xylostella.In the present study,we aimed to confirm the resistance risk,cross-resistance,and mechanisms of resistance to thiotraniliprole in P.xylostella.After 40 consecutive generations of thiotraniliprole selection,we obtained a thiotraniliprole-resistance P.xylostella strain with a 5141.58-fold resistance ratio(RR)to thiotraniliprole.The overall realized heritability(h^(2))value of resistance was estimated as 0.9 using threshold trait analysis,indicating that the risk of developing resistance to thiotraniliprole is high in P.xylostella.The thiotraniliprole-resistant(TR)strain showed noticeable cross-resistance to chlorantraniliprole(RR=44670.05),cyantraniliprole(RR=7038.58),and tetrachlorantraniliprole(RR=1506.01),but no cross-resistance to tolfenpyrad,indoxacarb,diafenthiuron,or abamectin compared with the susceptible(S)strain.The enzyme assay data showed that the activities of glutathione-S transferase(GST),carboxylesterase(CarE),and the content of cytochrome P450 monooxygenase(P450s)were significantly higher in the TR strain than in the S strain.Sequencing of the full-length PxRyR cDNA revealed the gene site I4790K in the TR strain with a 100%frequency.This mutation in PxRyR likely underlies the high-level cross-resistance between thiotraniliprole and three other diamide insecticides.These findings provide valuable information for optimizing resistance management strategies to delay thiotraniliprole resistance development and ensure sustainable control of P.xylostella.展开更多
Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinat...Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinate dehydrogenase inhibitor(SDHI),has been found as a promising fungicide for the efficient control of SCLB,however,resistance of C.heterostrophus to Pyd has not been studied well.Here,five Pyd-resistant mutants were generated through fungicide adaptation.Sequence alignment analysis revealed that these mutants primarily mutated in ChSdhB and ChSdhD,with three genotypes:ChSdhB^(H277Y),ChSdhB^(I279T)and ChSdhD^(H133Y),exhibiting two distinct categories of resistance:high resistance(HR)and moderate resistance(MR),among which the resistance factors were 214.22 and 44.33-53.67,respectively.These mutants were more pathogenic than the wild-type parental strains,but there was a significant reduction in mycelial growth rate and sporulation in the resistant mutants,indicating a significant fitness cost associated with resistance to Pyd.In addition,this study revealed a positive cross-resistance between Pyd and another SDHI fungicide cyclobutrifluram.However,no cross-resistance was found between Pyd and other classes of fungicides,including prochloraz,fludioxonil,iprodione or pyraclostrobin.Homology modeling and molecular docking further confirmed that point mutations of ChSdhB^(H277Y),ChSdhB^(I279T),and ChSdhD^(H133Y)could reduce binding affinity between Pyd and its target subunits from-74.07,-74.07,-152.52 kcal mol^(-1)to-3.90,-4.95,-9.93 kcal mol^(-1),respectively.These findings not only provided valuable insights for managing SCLB caused by C.heterostrophus,but also enhanced our understanding of molecular mechanism underlying plant pathogen resistance to Pyd.展开更多
Insulin resistance(IR)is widely recognized as a key contributor to metabolic disorders,and various surrogate indices have been developed to estimate IR in clinical and research settings.The hyperinsulinemic-euglycemic...Insulin resistance(IR)is widely recognized as a key contributor to metabolic disorders,and various surrogate indices have been developed to estimate IR in clinical and research settings.The hyperinsulinemic-euglycemic clamp is considered the gold standard method for assessing insulin resistance due to its precision;however,its complexity limits its widespread clinical application.Consequently,surrogate indices derived from fasting and post-load glucose and insulin levels have been developed to estimate IR,facilitating early detection and risk stratification in metabolic disorders.This mini-review discusses the clinical utility,strengths,and limitations of key IR indices,including the homeostasis model assessment of IR,quantitative insulin sensitivity check index,Matsuda index,and triglyceride-glucose index.Overall,the evidence presented to date suggests that these indices provide valuable estimates of IR in various popula-tions.Yet,their applicability varies depending on ethnic background,disease status,and clinical setting.Integrating these indices into routine clinical practice and research could improve metabolic risk assessment and guide preventive interventions.Further investigations are necessary to refine their accuracy and determine optimal cut-off values for various populations.展开更多
Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter...Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time.展开更多
Postgrouting at the pile tip enhances the performance of cast-in-place piles.To clarify the performance of tip and side resistances,this study analyzed static load test data from two test piles before and after grouti...Postgrouting at the pile tip enhances the performance of cast-in-place piles.To clarify the performance of tip and side resistances,this study analyzed static load test data from two test piles before and after grouting.Mechanisms underlying an improvement in tip resistance and the influence of postgrouting on side resistance were investigated via theoretical analysis.Finally,a design method for tip resistance control via settlement was proposed.Results indicate that the ultimate bearing capacity of piles increases after grouting compared to before,underscoring the importance of tip grouting in gravelly soils and its profound impact on load transmission in pile foundations.Postgrouting at the pile tip enhances the strength as well as initial stiffness of the bearing stratum,ultimately elevating the overall pile foundation-bearing capacity.Additionally,tip grouting helps in strengthening over-all side resistance,especially around the pile tip.The grouting procedure has an impact on the soil’s arching effect at the pile tip;the extent of the arching effect and an increase in horizontal tension close to the pile tip are positively correlated with the effectiveness of grouting reinforcement.The design method for tip resistance control via settlement based on measured data statistics was validated using engineering examples,and the method has a practical reference value.展开更多
BACKGROUND Antibiotic resistance is a key factor influencing the treatment outcomes of Helicobacter pylori(H.pylori)infection.The antibiotic resistance spectrum of H.pylori varies in different regions.We investigated ...BACKGROUND Antibiotic resistance is a key factor influencing the treatment outcomes of Helicobacter pylori(H.pylori)infection.The antibiotic resistance spectrum of H.pylori varies in different regions.We investigated the current status of antibiotic resistance of H.pylori in Hunan Province and analyzed the factors related to such resistance to provide strategies for the accurate clinical treatment of H.pylori infection.AIM To understand the antibiotic resistance of H.pylori in Hunan Province and provide guidance for the clinical treatment of H.pylori infection.METHODS This study selected patients who underwent gastroscopy in five hospitals in Hunan Province from April 2022 to April 2023.The sensitivity of H.pylori to clarithromycin,levofloxacin,metronidazole,amoxicillin,furazolidone,and tetracycline was detected using the Agar dilution method.RESULTS H.pylori strains from a total of 566 patients were isolated and identified.The resistance rates of H.pylori strains to clarithromycin,levofloxacin,metronidazole,amoxicillin,furazolidone,and tetracycline were 49.2%,37.8%,76.1%,2.3%,1.4%,and 0.7%,respectively.The resistance rates to clarithromycin,levofloxacin,and metronidazole were high in the four regions of Hunan Province,and the overall resistance rates in central Hunan Province were higher than those in other regions.The resistance rates of H.pylori strains to clarithromycin and levofloxacin were significantly different among the different age groups(P<0.05),with the elderly group having a higher resistance rate than the young group.The resistance rate of H.pylori strains to clarithromycin was greater in patients with atrophic gastritis,and the resistance rate to levofloxacin was the lowest in patients with peptic ulcers.CONCLUSION The resistance rate of H.pylori to amoxicillin,clarithromycin,and metronidazole is high in Hunan Province.Age,stomach disease,and H.pylori reinfection may affect the antibiotic resistance of H.pylori.展开更多
To enhance the corrosion resistance and electrical conductivity, the surface of 316L stainless steel was modified by the ion implantation of Mo. By investigating various accelerating voltages and implantation doses, i...To enhance the corrosion resistance and electrical conductivity, the surface of 316L stainless steel was modified by the ion implantation of Mo. By investigating various accelerating voltages and implantation doses, it was found that the corrosion resistance of stainless steel was enhanced by 50%-80% and the surface conductivity by 15%-28% at most. The minimum stabilized current density is 0.72 μA/cm^(2). This is due to the formation of a Cr and Mo riched modified layer on the surface of the stainless steel. Mo oxides synergize with Cr oxides in the form of a solid solution to enhance the corrosion resistance of passivation films on the stainless steel surface. The optimum parameters were Cr in the proportion of 6%-8% and Mo in the proportion of 4%-5%.展开更多
The predominant causal agent of poplar leaf blight is the pathogenic fungus Alternaria alternata (Fr.) Keissl., which exhibits host specificity toward Populus species. To elucidate the molecular response mechanisms of...The predominant causal agent of poplar leaf blight is the pathogenic fungus Alternaria alternata (Fr.) Keissl., which exhibits host specificity toward Populus species. To elucidate the molecular response mechanisms of A. alternata under fludioxonil fungicide stress, the fungus was cultured at the half-maximal effective concentration (EC₅₀) of fludioxonil. Transcriptomic and metabolomic profiles were analyzed using mycelia harvested under these conditions. Comparative analysis revealed 1,001 differentially expressed genes (DEGs) in the resistant strain (RS) relative to the wild-type strain (WT), comprising 628 upregulated and 373 downregulated genes. Concurrently, 524 differentially accumulated metabolites (DAMs) were identified, with 336 upregulated and 188 downregulated metabolites. KEGG pathway enrichment demonstrated pronounced upregulation in glycerophospholipid metabolism, α-linolenic acid metabolism, nucleic acid biosynthesis, and glycosylation processes. Conversely, arachidonic acid and galactose metabolism pathways were suppressed. Significant downregulation was observed in phosphatidylinositol signaling, aflatoxin biosynthesis, and cutin/suberin/wax biosynthesis pathways. Transcriptomic profiling further indicated that upregulated DEGs were predominantly associated with amino sugar/nucleotide sugar metabolism, ABC transporters, aflatoxin biosynthesis, and purine metabolism, while downregulated DEGs were enriched in N-glycan biosynthesis, endoplasmic reticulum protein processing, steroid biosynthesis, and riboflavin metabolism. Fludioxonil exerted substantial inhibitory effects on fungal growth, pathogenicity, and metabolic activity. Mechanistically, A. alternata counteracted fungicide-induced stress through modulation of its antioxidant defense system. This integrative multi-omics study delineates the dynamic gene expression and metabolic reprogramming in A. alternata under fludioxonil exposure, providing novel insights into potential molecular targets and informing the development of next-generation fungicidal strategies for phytopathogen control.展开更多
BACKGROUND Cardiovascular disease represents a major complication in patients with type 2 diabetes mellitus(T2DM),with insulin resistance(IR)recognized as a key underlying pathophysiological mechanism.The metabolic sc...BACKGROUND Cardiovascular disease represents a major complication in patients with type 2 diabetes mellitus(T2DM),with insulin resistance(IR)recognized as a key underlying pathophysiological mechanism.The metabolic score for IR(METS-IR),a simple,non-invasive,and insulin-independent surrogate marker of IR,has been validated for risk stratification and prognostic assessment in conditions such as hypertension,ischemic cardiomyopathy,and T2DM.Monitoring fluctuations in METS-IR levels among individuals with T2DM may facilitate early identification of elevated cardiovascular risk and inform timely therapeutic adjustments.AIM To investigate the association between METS-IR and cardiovascular risk in patients with T2DM and to evaluate its potential utility as a predictive biomarker.METHODS This study represents a secondary analysis of a multicenter randomized controlled trial,ultimately including 10191 patients with T2DM aged 40 years to 79 years,with a follow-up duration of approximately 10 years.Baseline METS-IR was calculated using triglycerides,body mass index,high-density lipoprotein cholesterol and fasting plasma glucose.The predictive value of METS-IR for major adverse cardiovascular events(MACEs),all-cause mortality,congestive heart failure,and major coronary heart disease events,was assessed using Cox proportional hazards models,restricted cubic spline analysis,and stratified subgroup analyses.Multivariable adjustments were performed to account for potential confounding factors.RESULTS The incidence of MACEs increased steadily across higher METS-IR quartiles.After adjusting for multiple confounding factors,hazard ratios comparing the highest to the lowest METS-IR quartile were 1.25[95%confidence interval(CI):1.08-1.45]for MACEs,1.55(95%CI:1.23-1.96)for cardiovascular death,1.39(95%CI:1.21-1.59)for allcause mortality,2.22(95%CI:1.74-2.82)for congestive heart failure,and 1.35(95%CI:1.17-1.56)for major coronary heart disease.Restricted cubic spline analysis supported a positive,dose-dependent relationship between rising METS-IR levels and cardiovascular risk.Moreover,adding METS-IR to conventional risk prediction models enhanced their performance,as evidenced by improvements in the C-statistic,net reclassification improvement,and integrated discrimination improvement.Subgroup analyses indicated possible interactions between METS-IR,hemoglobin A1c levels,and aspirin therapy.CONCLUSION METS-IR shows a strong correlation with cardiovascular risk in individuals with T2DM.Tracking METS-IR levels could enhance risk assessment and the prediction of cardiovascular events.展开更多
Verticillium wilt,caused by the infamous pathogen Verticillium dahliae,presents a primary constraint on cotton cul-tivation worldwide.The complexity of disease resistance in cotton and the largely unexplored interacti...Verticillium wilt,caused by the infamous pathogen Verticillium dahliae,presents a primary constraint on cotton cul-tivation worldwide.The complexity of disease resistance in cotton and the largely unexplored interaction dynamics between the cotton plant host and V.dahliae pathogen pose a crucial predicament for effectively managing cotton Verticillium wilt.Nevertheless,the most cost-effective approach to controlling this disease involves breeding and cul-tivating resistant cotton varieties,demanding a meticulous analysis of the mechanisms underlying cotton’s resistance to Verticillium wilt and the identification of pivotal genes.These aspects constitute focal points in disease-resistance breeding programs.In this review,we comprehensively discuss genetic inheritance associated with Verticillium wilt resistance in cotton,the advancements in molecular markers for disease resistance,the functional investiga-tion of resistance genes in cotton,the analysis of pathogenicity genes in V.dahliae,as well as the intricate interplay between cotton and this fungus.Moreover,we delve into the future prospects of cutting-edge research on cotton Verticillium wilt,aiming to proffer valuable insights for the effective management of this devastating fungus.展开更多
When the War of Resistance Against Japanese Aggression broke out,a large number of Tibetan Buddhist monks who loved the country also participated in this all-out war.
Soybean frogeye leaf spot(FLS)disease is a worldwide disease caused by Cercospora sojina Hara.It is one of the major diseases suffered by soybean during the growth cycle,which seriously damages the yield and seed qual...Soybean frogeye leaf spot(FLS)disease is a worldwide disease caused by Cercospora sojina Hara.It is one of the major diseases suffered by soybean during the growth cycle,which seriously damages the yield and seed quality of soybean.The current resistant varieties are difficult to meet the production demand.The breeders have identified 50 different physiological small species and discussed the physiological and biochemical characteristics of soybean resistance to FLS.In soybean disease resistance breeding,resistance resources are screened for the main physiological races in different countries,resistance materials are created,more than 100 genome regions associated with resistance are located,and 12 resistance-related genes are identified.In order to promote the research of soybean disease resistance breeding,this paper expounded and analyzed the pathogenesis characteristics of soybean FLS,the division of races,the physiological and biochemical mechanism of soybean resistance to FLS disease,quantitative trait locus(QTL),quantitative trait nucleotides(QTN),genes of resistance sites,the screening of resistant germplasm resources,and the breeding of new varieties,so as to gain an in-depth understanding of the pathogenesis principle of soybean FLS disease.In order to provide a theoretical basis and technical support for the breeding of soybean FLS disease,the resistance mechanism of soybean FLS disease was analyzed from the molecular level.展开更多
Rapid technological advancements drive miniaturization and high energy density in devices,thereby increasing nanoscale thermal management demands and urging development of higher spatial resolution technologies for th...Rapid technological advancements drive miniaturization and high energy density in devices,thereby increasing nanoscale thermal management demands and urging development of higher spatial resolution technologies for thermal imaging and transport research.Here,we introduce an approach to measure nanoscale thermal resistance using in situ inelastic scanning transmission electron microscopy.By constructing unidirectional heating flux with controlled temperature gradients and analyzing electron energy-loss/gain signals under optimized acquisition conditions,nanometer-resolution in mapping phonon apparent temperature is achieved.Thus,interfacial thermal resistance is determined by calculating the ratio of interfacial temperature difference to bulk temperature gradient.This methodology enables direct measurement of thermal transport properties for atomic-scale structural features(e.g.,defects and heterointerfaces),resolving critical structure-performance relationships,providing a useful tool for investigating thermal phenomena at the(sub-)nanoscale.展开更多
To enhance the resistance of honeycomb sandwich panel against local impact,this study delved into the matching relationship between face sheets and core.An integrated approach,combining experiment,simulation,and theor...To enhance the resistance of honeycomb sandwich panel against local impact,this study delved into the matching relationship between face sheets and core.An integrated approach,combining experiment,simulation,and theoretical methods,was used.Local loading experiments were conducted to validate the accuracy of the finite element model.Furthermore,a control equation was formulated to correlate structural parameters with response modes,and a matching coefficientλ(representing the ratio of core thickness to face sheet thickness)was introduced to establish a link between these parameters and impact characteristics.A demand-driven reverse design methodology for structural parameters was developed,with numerical simulations employed to assess its effectiveness.The results indicate that the proposed theory can accurately predict response modes and key indicators.An increase in theλbolsters the structural indentation resistance while concurrently heightens the likelihood of penetration.Conversely,a decrease in theλimproves the resistance to penetration,albeit potentially leading to significant deformations in the rear face sheet.Numerical simulations demonstrate that the reverse design methodology significantly enhances the structural penetration resistance.Comparative analyses indicate that appropriate matching reduces indentation depth by 27.4% and indentation radius by 41.8%of the proposed structure.展开更多
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
In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powder...In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed mixers.Microstructure evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were investigated.Results indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LSA with Mn+W_(2)C and Mn+NiWC while SiC totally dissolved into the high Mn matrix when adding Mn+SiC.Ni as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C powder.An improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.展开更多
基金the support of the Science and Technology Commission of Shanghai Municipality(STCSM,No.20dz1203600)the Experimental Center of Materials Science and Engineering in Tongji University。
文摘Epoxy resin is widely used in electronic packaging due to its exceptional performance,particularly the low-temperature curable thiol/epoxy system,which effectively minimizes thermal damage to sensitive electronic components.However,the majority of commercial thiol curing agents contain hydrolysable ester bonds and lack rigid structures,which induces most of thiol/epoxy systems still suffering from unsatisfactory heat resistance and hygrothermal resistance,significantly hindering their application in electronic packaging.In this study,we synthesized a tetrafunctional thiol compound,bis[3-(3-sulfanylpropyl)-4-(3-sulfanylpropoxy)phenyl]sulfone(TMBPS)with rigid and ester-free structures to replace traditional commercial thiol curing agents,pentaerythritol tetra(3-mercaptopropionate)(PETMP).Compared to the PETMP/epoxy system,the TMBPS/epoxy system exhibited superior comprehensive properties.The rigid structures of bisphenol S-type tetrathiol enhanced the heat resistance and mechanical properties of TMBPS/epoxy resin cured products,outperforming those of PETMP/epoxy resin cured products.Notably,the glass transition temperature of TMBPS/epoxy resin cured products was 74.2℃which was 11.8°C higher than that of PETMP cured products.Moreover,the ester-free structure in TMBPS contributed to its enhanced resistance to chemicals and hygrothermal conditions.After undergoing 1000 h of hightemperature and high-humidity aging,the tensile strength and adhesion strength of TMBPS-cured products were 73.33 MPa and 3.39 MPa,respectively exceeding 100%and 40%of their initial values,while PETMP-cured products exhibited a complete loss of both tensile strength and adhesion strength.This study provides a strategy for obtaining thermosetting polymers that can be cured at low temperatures and exhibit excellent comprehensive properties.
基金supported by the University Synergy Innovation Program of Anhui Province(Grant Nos.GXXT-2023-025 and GXXT-2023-026)Natural Science Foundation of Anhui Province(Grant Nos.2008085ME149,2308085QE132 and 2308065ME171)Anhui University Scientific Research Project(Grant Nos.2022AH040247,2023AH051660,2023AH051670 and 2023AH051671).
文摘To improve the high-temperature service properties of coppery tuyere,Co06 coating with a Ni60A interlayer was prepared on copper by plasma cladding.Ni60A interlayer acted as a bridge to promote the element diffusion,thus achieving metallurgical bonding.Due to the strengthening effect ofγ-Co,Cr_(23)C_(6)and Cr_(7)C_(3)phases,the wear resistance of Co06–Ni60A coating was much higher than that of copper substrate.As the temperature increased,the wear resistance of coating decreased first and then increased.The coating exhibited better wear resistance at 600℃ due to the oxidation wear mechanism.Compared with copper substrate and Ni60A,the oxidation resistance of Co06 was increased by 6.0 and 1.9 times,respectively.For melting loss resistance,Co06–Ni60A coating was superior to Ni60A single-layer coating,but the molten iron can still form a micro-metallurgical bonding with the coating surface.
基金support from Region Stockholm,ALF-project(FoUI-960041)Open Access funding is provided by Karolinska Institute(both to IM)。
文摘Type 2 diabetes mellitus and Parkinson's disease are chronic diseases linked to a growing pandemic that affects older adults and causes significant socio-economic burden.Epidemiological data supporting a close relationship between these two aging-related diseases have resulted in the investigation of shared pathophysiological molecular mechanisms.Impaired insulin signaling in the brain has gained increasing attention during the last decade and has been suggested to contribute to the development of Parkinson's disease through the dysregulation of several pathological processes.The contribution of type 2 diabetes mellitus and insulin resistance in neurodegeneration in Parkinson's disease,with emphasis on brain insulin resistance,is extensively discussed in this article and new therapeutic strategies targeting this pathological link are presented and reviewed.
基金National Natural Science Foundation of China(52071126)Natural Science Foundation of Tianjin City,China(22JCQNJC01240)+2 种基金Central Guidance on Local Science and Technology Development Fund of Hebei Province(226Z1009G)Special Funds for Science and Technology Innovation in Hebei(2022X19)Anhui Provincial Natural Science Foundation(2308085ME135)。
文摘Co-based alloy coating was prepared on Zr alloy using laser melting and cladding technique to study the difference in the high-temperature oxidation behavior between pure metal Co coatings and Co-T800 alloy coatings,as well as the wear resistance of the coatings.Besides,the effect of changing the laser melting process on the coatings was also investigated.The oxidation mass gain at 800–1200℃and the high-temperature oxidation behavior during high-temperature treatment for 1 h of two coated Zr alloy samples were studied.Results show that the Co coating and the Co-T800 coating have better resistance against high-temperature oxidation.After oxidizing at 1000℃for 1 h,the thickness of the oxide layer of the uncoated sample was 241.0μm,whereas that of the sample with Co-based coating is only 11.8–35.5μm.The friction wear test shows that the depth of the abrasion mark of the coated sample is only 1/2 of that of the substrate,indicating that the hardness and wear resistance of the Zr substrate are greatly improved.The disadvantage of Co-based coatings is the inferior corrosion resistance in 3.5wt%NaCl solution.
基金Supported by the Zhejiang Provincial Public Welfare Technology Application Research Program(No:LGN21C140001).
文摘Plutella xylostella,a major pest of cruciferous vegetables worldwide,has developed resistance to diamide insecticides.Thiotraniliprole,a novel synthetic diamide insecticide,exhibits excellent activity against P.xylostella.In the present study,we aimed to confirm the resistance risk,cross-resistance,and mechanisms of resistance to thiotraniliprole in P.xylostella.After 40 consecutive generations of thiotraniliprole selection,we obtained a thiotraniliprole-resistance P.xylostella strain with a 5141.58-fold resistance ratio(RR)to thiotraniliprole.The overall realized heritability(h^(2))value of resistance was estimated as 0.9 using threshold trait analysis,indicating that the risk of developing resistance to thiotraniliprole is high in P.xylostella.The thiotraniliprole-resistant(TR)strain showed noticeable cross-resistance to chlorantraniliprole(RR=44670.05),cyantraniliprole(RR=7038.58),and tetrachlorantraniliprole(RR=1506.01),but no cross-resistance to tolfenpyrad,indoxacarb,diafenthiuron,or abamectin compared with the susceptible(S)strain.The enzyme assay data showed that the activities of glutathione-S transferase(GST),carboxylesterase(CarE),and the content of cytochrome P450 monooxygenase(P450s)were significantly higher in the TR strain than in the S strain.Sequencing of the full-length PxRyR cDNA revealed the gene site I4790K in the TR strain with a 100%frequency.This mutation in PxRyR likely underlies the high-level cross-resistance between thiotraniliprole and three other diamide insecticides.These findings provide valuable information for optimizing resistance management strategies to delay thiotraniliprole resistance development and ensure sustainable control of P.xylostella.
基金supported by the National Key Research and Development Program of China(2023YFD1401504)the Open Project of Anhui Province Key Laboratory of Pesticide Resistance Management on Grain and Vegetable Pests,China(PKLPRMGVP202402)+3 种基金the Programs for the Scientific Research Activities of Academic and Technical Leaders of Anhui Province,China(2020D251)the Development Fund for Talent Personnel of Anhui Agricultural University,China(rc342006)the University Synergy Innovation Program of Anhui Province,China(GXXT-2021-059)Anhui Province Agricultural Eco-Environmental Protection and Quality Safety Industry Technology System,China。
文摘Southern corn leaf blight(SCLB)caused by Cochliobolus heterostrophus,is a widespread foliar disease that has a substantial impact on maize yield in the Huang-Huai-Hai Region of China.Pydiflumetofen(Pyd),a new succinate dehydrogenase inhibitor(SDHI),has been found as a promising fungicide for the efficient control of SCLB,however,resistance of C.heterostrophus to Pyd has not been studied well.Here,five Pyd-resistant mutants were generated through fungicide adaptation.Sequence alignment analysis revealed that these mutants primarily mutated in ChSdhB and ChSdhD,with three genotypes:ChSdhB^(H277Y),ChSdhB^(I279T)and ChSdhD^(H133Y),exhibiting two distinct categories of resistance:high resistance(HR)and moderate resistance(MR),among which the resistance factors were 214.22 and 44.33-53.67,respectively.These mutants were more pathogenic than the wild-type parental strains,but there was a significant reduction in mycelial growth rate and sporulation in the resistant mutants,indicating a significant fitness cost associated with resistance to Pyd.In addition,this study revealed a positive cross-resistance between Pyd and another SDHI fungicide cyclobutrifluram.However,no cross-resistance was found between Pyd and other classes of fungicides,including prochloraz,fludioxonil,iprodione or pyraclostrobin.Homology modeling and molecular docking further confirmed that point mutations of ChSdhB^(H277Y),ChSdhB^(I279T),and ChSdhD^(H133Y)could reduce binding affinity between Pyd and its target subunits from-74.07,-74.07,-152.52 kcal mol^(-1)to-3.90,-4.95,-9.93 kcal mol^(-1),respectively.These findings not only provided valuable insights for managing SCLB caused by C.heterostrophus,but also enhanced our understanding of molecular mechanism underlying plant pathogen resistance to Pyd.
文摘Insulin resistance(IR)is widely recognized as a key contributor to metabolic disorders,and various surrogate indices have been developed to estimate IR in clinical and research settings.The hyperinsulinemic-euglycemic clamp is considered the gold standard method for assessing insulin resistance due to its precision;however,its complexity limits its widespread clinical application.Consequently,surrogate indices derived from fasting and post-load glucose and insulin levels have been developed to estimate IR,facilitating early detection and risk stratification in metabolic disorders.This mini-review discusses the clinical utility,strengths,and limitations of key IR indices,including the homeostasis model assessment of IR,quantitative insulin sensitivity check index,Matsuda index,and triglyceride-glucose index.Overall,the evidence presented to date suggests that these indices provide valuable estimates of IR in various popula-tions.Yet,their applicability varies depending on ethnic background,disease status,and clinical setting.Integrating these indices into routine clinical practice and research could improve metabolic risk assessment and guide preventive interventions.Further investigations are necessary to refine their accuracy and determine optimal cut-off values for various populations.
基金supported by the Joint Funds of the National Natural Science Foundation of China(U21A20272)。
文摘Cronobacter spp.has strong resistance to desiccation and high permeability in Enterobacteriaceae,and powdered infant formula(PIF)is one of the main contamination routes.In recent years,the contamination of Cronobacter spp.in PIF incidents occurs from time to time,causing infant serious diseases or death.In this investigation,matrix-assisted laser desorption/ionization time of flight mass spectrometry was used to identify the phenotypes of 35 Cronobacter strains isolated from PIF and its processing environment.Subsequently,the isolates were evaluated for drying and osmotic pressure tolerance.The results showed that the deactivation rate of the strains ranged from 9.01%to 77.57%,and the highest osmotic pressure condition the strains could tolerate was 6 g/100 mL Na Cl.In addition,there was a positive correlation between biofilm formation ability and desiccation resistance.Combined with transcriptomics,Cronobacter spp.could activate biofilm synthesis,produce more trehalose,accumulate betaine and electrolytes to stabilize intracellular structure under the two treatment conditions.A total of 31 and 43 genes were found related to desiccation and permeability resistance,respectively.And some genes(cysM,thuF,ycjO,etc.)were found to be associated with two tolerances for the first time.
基金The National Natural Science Foundation of China(No.52008100,52178317)the Natural Science Foundation of Jiangsu Province(No.BK20200400)+1 种基金China Postdoctoral Science Foundation(No.2022M723534)the Natural Science Foundation of Jiangsu Higher Education Institutions of China(No.23KJA560005).
文摘Postgrouting at the pile tip enhances the performance of cast-in-place piles.To clarify the performance of tip and side resistances,this study analyzed static load test data from two test piles before and after grouting.Mechanisms underlying an improvement in tip resistance and the influence of postgrouting on side resistance were investigated via theoretical analysis.Finally,a design method for tip resistance control via settlement was proposed.Results indicate that the ultimate bearing capacity of piles increases after grouting compared to before,underscoring the importance of tip grouting in gravelly soils and its profound impact on load transmission in pile foundations.Postgrouting at the pile tip enhances the strength as well as initial stiffness of the bearing stratum,ultimately elevating the overall pile foundation-bearing capacity.Additionally,tip grouting helps in strengthening over-all side resistance,especially around the pile tip.The grouting procedure has an impact on the soil’s arching effect at the pile tip;the extent of the arching effect and an increase in horizontal tension close to the pile tip are positively correlated with the effectiveness of grouting reinforcement.The design method for tip resistance control via settlement based on measured data statistics was validated using engineering examples,and the method has a practical reference value.
基金Supported by the National Natural Science Foundation of China,No.82270594the Independent Exploration and Innovation Project of Central South University,No.2024ZZTS0966.
文摘BACKGROUND Antibiotic resistance is a key factor influencing the treatment outcomes of Helicobacter pylori(H.pylori)infection.The antibiotic resistance spectrum of H.pylori varies in different regions.We investigated the current status of antibiotic resistance of H.pylori in Hunan Province and analyzed the factors related to such resistance to provide strategies for the accurate clinical treatment of H.pylori infection.AIM To understand the antibiotic resistance of H.pylori in Hunan Province and provide guidance for the clinical treatment of H.pylori infection.METHODS This study selected patients who underwent gastroscopy in five hospitals in Hunan Province from April 2022 to April 2023.The sensitivity of H.pylori to clarithromycin,levofloxacin,metronidazole,amoxicillin,furazolidone,and tetracycline was detected using the Agar dilution method.RESULTS H.pylori strains from a total of 566 patients were isolated and identified.The resistance rates of H.pylori strains to clarithromycin,levofloxacin,metronidazole,amoxicillin,furazolidone,and tetracycline were 49.2%,37.8%,76.1%,2.3%,1.4%,and 0.7%,respectively.The resistance rates to clarithromycin,levofloxacin,and metronidazole were high in the four regions of Hunan Province,and the overall resistance rates in central Hunan Province were higher than those in other regions.The resistance rates of H.pylori strains to clarithromycin and levofloxacin were significantly different among the different age groups(P<0.05),with the elderly group having a higher resistance rate than the young group.The resistance rate of H.pylori strains to clarithromycin was greater in patients with atrophic gastritis,and the resistance rate to levofloxacin was the lowest in patients with peptic ulcers.CONCLUSION The resistance rate of H.pylori to amoxicillin,clarithromycin,and metronidazole is high in Hunan Province.Age,stomach disease,and H.pylori reinfection may affect the antibiotic resistance of H.pylori.
基金supported by the National Natural Science Foundation of China(22005140)Scientific Research Foundation for the Introduction of Talents by Nanjing Institute of Technology(YKJ201996)Postgraduate Research&Practice Innovation Program of Jiangsu Province(KYCX22_1370).
文摘To enhance the corrosion resistance and electrical conductivity, the surface of 316L stainless steel was modified by the ion implantation of Mo. By investigating various accelerating voltages and implantation doses, it was found that the corrosion resistance of stainless steel was enhanced by 50%-80% and the surface conductivity by 15%-28% at most. The minimum stabilized current density is 0.72 μA/cm^(2). This is due to the formation of a Cr and Mo riched modified layer on the surface of the stainless steel. Mo oxides synergize with Cr oxides in the form of a solid solution to enhance the corrosion resistance of passivation films on the stainless steel surface. The optimum parameters were Cr in the proportion of 6%-8% and Mo in the proportion of 4%-5%.
基金supported by the Northeast Asia Biodiversity Research Center(grant number 411147021003).
文摘The predominant causal agent of poplar leaf blight is the pathogenic fungus Alternaria alternata (Fr.) Keissl., which exhibits host specificity toward Populus species. To elucidate the molecular response mechanisms of A. alternata under fludioxonil fungicide stress, the fungus was cultured at the half-maximal effective concentration (EC₅₀) of fludioxonil. Transcriptomic and metabolomic profiles were analyzed using mycelia harvested under these conditions. Comparative analysis revealed 1,001 differentially expressed genes (DEGs) in the resistant strain (RS) relative to the wild-type strain (WT), comprising 628 upregulated and 373 downregulated genes. Concurrently, 524 differentially accumulated metabolites (DAMs) were identified, with 336 upregulated and 188 downregulated metabolites. KEGG pathway enrichment demonstrated pronounced upregulation in glycerophospholipid metabolism, α-linolenic acid metabolism, nucleic acid biosynthesis, and glycosylation processes. Conversely, arachidonic acid and galactose metabolism pathways were suppressed. Significant downregulation was observed in phosphatidylinositol signaling, aflatoxin biosynthesis, and cutin/suberin/wax biosynthesis pathways. Transcriptomic profiling further indicated that upregulated DEGs were predominantly associated with amino sugar/nucleotide sugar metabolism, ABC transporters, aflatoxin biosynthesis, and purine metabolism, while downregulated DEGs were enriched in N-glycan biosynthesis, endoplasmic reticulum protein processing, steroid biosynthesis, and riboflavin metabolism. Fludioxonil exerted substantial inhibitory effects on fungal growth, pathogenicity, and metabolic activity. Mechanistically, A. alternata counteracted fungicide-induced stress through modulation of its antioxidant defense system. This integrative multi-omics study delineates the dynamic gene expression and metabolic reprogramming in A. alternata under fludioxonil exposure, providing novel insights into potential molecular targets and informing the development of next-generation fungicidal strategies for phytopathogen control.
基金Supported by the Key Research and Development Plan of Hunan Province,No.2022SK2013Central South University,No.2024ZZTS0931.
文摘BACKGROUND Cardiovascular disease represents a major complication in patients with type 2 diabetes mellitus(T2DM),with insulin resistance(IR)recognized as a key underlying pathophysiological mechanism.The metabolic score for IR(METS-IR),a simple,non-invasive,and insulin-independent surrogate marker of IR,has been validated for risk stratification and prognostic assessment in conditions such as hypertension,ischemic cardiomyopathy,and T2DM.Monitoring fluctuations in METS-IR levels among individuals with T2DM may facilitate early identification of elevated cardiovascular risk and inform timely therapeutic adjustments.AIM To investigate the association between METS-IR and cardiovascular risk in patients with T2DM and to evaluate its potential utility as a predictive biomarker.METHODS This study represents a secondary analysis of a multicenter randomized controlled trial,ultimately including 10191 patients with T2DM aged 40 years to 79 years,with a follow-up duration of approximately 10 years.Baseline METS-IR was calculated using triglycerides,body mass index,high-density lipoprotein cholesterol and fasting plasma glucose.The predictive value of METS-IR for major adverse cardiovascular events(MACEs),all-cause mortality,congestive heart failure,and major coronary heart disease events,was assessed using Cox proportional hazards models,restricted cubic spline analysis,and stratified subgroup analyses.Multivariable adjustments were performed to account for potential confounding factors.RESULTS The incidence of MACEs increased steadily across higher METS-IR quartiles.After adjusting for multiple confounding factors,hazard ratios comparing the highest to the lowest METS-IR quartile were 1.25[95%confidence interval(CI):1.08-1.45]for MACEs,1.55(95%CI:1.23-1.96)for cardiovascular death,1.39(95%CI:1.21-1.59)for allcause mortality,2.22(95%CI:1.74-2.82)for congestive heart failure,and 1.35(95%CI:1.17-1.56)for major coronary heart disease.Restricted cubic spline analysis supported a positive,dose-dependent relationship between rising METS-IR levels and cardiovascular risk.Moreover,adding METS-IR to conventional risk prediction models enhanced their performance,as evidenced by improvements in the C-statistic,net reclassification improvement,and integrated discrimination improvement.Subgroup analyses indicated possible interactions between METS-IR,hemoglobin A1c levels,and aspirin therapy.CONCLUSION METS-IR shows a strong correlation with cardiovascular risk in individuals with T2DM.Tracking METS-IR levels could enhance risk assessment and the prediction of cardiovascular events.
基金supported by National Natural Science Foundation of China(32201752)Xinjiang Tianchi Talents Program (TCYC2023TP02)Key Project of the Natural Science Foundation of Xinjiang Production and Construction Corps (2024DA001)
文摘Verticillium wilt,caused by the infamous pathogen Verticillium dahliae,presents a primary constraint on cotton cul-tivation worldwide.The complexity of disease resistance in cotton and the largely unexplored interaction dynamics between the cotton plant host and V.dahliae pathogen pose a crucial predicament for effectively managing cotton Verticillium wilt.Nevertheless,the most cost-effective approach to controlling this disease involves breeding and cul-tivating resistant cotton varieties,demanding a meticulous analysis of the mechanisms underlying cotton’s resistance to Verticillium wilt and the identification of pivotal genes.These aspects constitute focal points in disease-resistance breeding programs.In this review,we comprehensively discuss genetic inheritance associated with Verticillium wilt resistance in cotton,the advancements in molecular markers for disease resistance,the functional investiga-tion of resistance genes in cotton,the analysis of pathogenicity genes in V.dahliae,as well as the intricate interplay between cotton and this fungus.Moreover,we delve into the future prospects of cutting-edge research on cotton Verticillium wilt,aiming to proffer valuable insights for the effective management of this devastating fungus.
文摘When the War of Resistance Against Japanese Aggression broke out,a large number of Tibetan Buddhist monks who loved the country also participated in this all-out war.
基金Supported by the 14th Five-Year National Key Research and Development Program(2021YFD1201103–01–05)the National Natural Science Foundation of China(32301819)the Cooperation Project of Research and Development Center between Wudalianchi Government and Northeast Agricultural University.
文摘Soybean frogeye leaf spot(FLS)disease is a worldwide disease caused by Cercospora sojina Hara.It is one of the major diseases suffered by soybean during the growth cycle,which seriously damages the yield and seed quality of soybean.The current resistant varieties are difficult to meet the production demand.The breeders have identified 50 different physiological small species and discussed the physiological and biochemical characteristics of soybean resistance to FLS.In soybean disease resistance breeding,resistance resources are screened for the main physiological races in different countries,resistance materials are created,more than 100 genome regions associated with resistance are located,and 12 resistance-related genes are identified.In order to promote the research of soybean disease resistance breeding,this paper expounded and analyzed the pathogenesis characteristics of soybean FLS,the division of races,the physiological and biochemical mechanism of soybean resistance to FLS disease,quantitative trait locus(QTL),quantitative trait nucleotides(QTN),genes of resistance sites,the screening of resistant germplasm resources,and the breeding of new varieties,so as to gain an in-depth understanding of the pathogenesis principle of soybean FLS disease.In order to provide a theoretical basis and technical support for the breeding of soybean FLS disease,the resistance mechanism of soybean FLS disease was analyzed from the molecular level.
基金supported by the National Natural Science Foundation of China(Grant No.52125307)the National Key R&D Program of China(Grant No.2021YFB3501500)the support from the New Cornerstone Science Foundation through the XPLORER PRIZE。
文摘Rapid technological advancements drive miniaturization and high energy density in devices,thereby increasing nanoscale thermal management demands and urging development of higher spatial resolution technologies for thermal imaging and transport research.Here,we introduce an approach to measure nanoscale thermal resistance using in situ inelastic scanning transmission electron microscopy.By constructing unidirectional heating flux with controlled temperature gradients and analyzing electron energy-loss/gain signals under optimized acquisition conditions,nanometer-resolution in mapping phonon apparent temperature is achieved.Thus,interfacial thermal resistance is determined by calculating the ratio of interfacial temperature difference to bulk temperature gradient.This methodology enables direct measurement of thermal transport properties for atomic-scale structural features(e.g.,defects and heterointerfaces),resolving critical structure-performance relationships,providing a useful tool for investigating thermal phenomena at the(sub-)nanoscale.
基金Project(2022A02480004)supported by the Major Project of China Railway Design CorporationProject(2023RC1011)supported by the Science and Technology Innovation Program of Hunan Province,China+2 种基金Project(2024JJ6515)supported by the Hunan Provincial Natural Science Foundation,ChinaProject(kq2402220)supported by the Natural Science Foundation of Changsha City,ChinaProject(52402438)supported by the National Natural Science Foundation of China。
文摘To enhance the resistance of honeycomb sandwich panel against local impact,this study delved into the matching relationship between face sheets and core.An integrated approach,combining experiment,simulation,and theoretical methods,was used.Local loading experiments were conducted to validate the accuracy of the finite element model.Furthermore,a control equation was formulated to correlate structural parameters with response modes,and a matching coefficientλ(representing the ratio of core thickness to face sheet thickness)was introduced to establish a link between these parameters and impact characteristics.A demand-driven reverse design methodology for structural parameters was developed,with numerical simulations employed to assess its effectiveness.The results indicate that the proposed theory can accurately predict response modes and key indicators.An increase in theλbolsters the structural indentation resistance while concurrently heightens the likelihood of penetration.Conversely,a decrease in theλimproves the resistance to penetration,albeit potentially leading to significant deformations in the rear face sheet.Numerical simulations demonstrate that the reverse design methodology significantly enhances the structural penetration resistance.Comparative analyses indicate that appropriate matching reduces indentation depth by 27.4% and indentation radius by 41.8%of the proposed structure.
基金supported by grants from NIH T32(DK007260,to WC)the Steno North American Fellowship awarded by the Novo Nordisk Foundation(NNF23OC0087108,to WC)+6 种基金STI2030-Major Projects(2021ZD0202700,to HY)the National Natural Science Foundation of China(32241004,to HY)the Natural Science Foundation of Zhejiang Province of China(LR24C090001,to HY)Key R&D Program of Zhejiang Province(2024SSYS0017,to HY)CAMS Innovation Fund for Medical Sciences(2019-12M-5-057,to HY)Fundamental Research Funds for the Central Universities(226-2022-00193,to HY)the Non-profit Central Research Institute Fund of Chinese Academy of Medical Sciences(2023-PT310-01,to HY)。
文摘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.
文摘In-situ formed high Mn steel coating reinforced by carbides was formed by laser surface alloying(LSA).Laser alloyed layers on 1Cr18Ni9Ti steel with Mn+W_(2)C(specimen A),Mn+NiWC(specimen B)and Mn+SiC(specimen C)powders were fabricated to improve the wear and corrosion behavior of 1Cr18Ni9Ti steel blades in high speed mixers.Microstructure evolution,phases,element distribution,microhardness,wear and corrosion behavior of the laser alloyed layers were investigated.Results indicated that high Mn steel matrix composites with undissolved W_(2)C,WC and other in-situ formed carbides were formed by LSA with Mn+W_(2)C and Mn+NiWC while SiC totally dissolved into the high Mn matrix when adding Mn+SiC.Ni as the binding phase in Ni-WC powder decreased the crack sensitivity of the alloyed layer as compared with the addition of W_(2)C powder.An improvement in average microhardness was achieved in the matrix in specimen A,B and C,with the value of 615,602 and 277 HV_(0.5),while that of the substrate was 212 HV_(0.5).The increase of microhardness,wear and corrosion resistance is highly corelated to microstructure,formed phases,type and content of carbides,micro-hardness and toughness of the alloyed layers.