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Sex-specific adaptive immune responses in spinal cord injury:Observations across species
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作者 Reena Kumari John C.Gensel 《Neural Regeneration Research》 2026年第8期3535-3536,共2页
Biological sex is increasingly recognized as a crucial factor in evaluating the translational value of preclinical spinal cord injury(SCI)studies.The rising incidence of SCI in females challenges the historical preced... Biological sex is increasingly recognized as a crucial factor in evaluating the translational value of preclinical spinal cord injury(SCI)studies.The rising incidence of SCI in females challenges the historical precedent of SCI being a male-dominated condition.In contrast,most basic science researchers utilize single-sex studies to minimize complications associated with bladder care in males(Stewart et al.,2020).The findings of our recent publication identify sexually dimorphic immune responses to SCI in both mice and pigs(Kumari et al.,2025).Here,we will highlight these findings and discuss the impact of sex on SCI inflammation and recovery. 展开更多
关键词 spinal cord injury adaptive immune responses PIGS biological sex INFLAMMATION sex specific mice spinal cord
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Seismic Responses Study of a Novel Main-Cable-Looped Suspension Bridge with Ground-Anchored Rods
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作者 Yu Wang Yao Song +5 位作者 Hongyong Yang Yu Zhu Jian Xu Dehao Ding Huahuai Sun Shunyao Cai 《Structural Durability & Health Monitoring》 2026年第2期174-194,共21页
Long-span suspension bridges are inherently vulnerable to earthquakes due to their low stiffness and damping.A novel design,the main-cable-looped(MCL)suspension bridge,features a looped main cable that alters the stru... Long-span suspension bridges are inherently vulnerable to earthquakes due to their low stiffness and damping.A novel design,the main-cable-looped(MCL)suspension bridge,features a looped main cable that alters the structure’s load transfer mechanism.The seismic response of this novel bridge type is not well understood,creating an urgent need for investigation to ensure its safety and performance.The global finite element model of this bridge was established by considering the interdependent behavior of the structure and the underlying soil.Based on the design seismic response spectrum,ground motion accelerations were selected,and the peak ground acceleration(PGA)was adjusted.The nonlinear time-history analysis method was adopted to calculate seismic responses of the novel MCL suspension bridge.A parametric study was conducted to investigate the effects of the PGA of seismic ground motion and the longitudinal position of ground-anchored rods on seismic responses of the novel suspension bridge.The research results show that under different seismic excitations with a design PGA of 0.1 g,the maximum longitudinal displacement at the tower top is 0.097 m,the maximum bending moment at the tower base reaches 2.20×10^(5)kN m,the maximum longitudinal displacement at the girder free end is 0.022 m,and the maximum vertical displacement at the girder mid-span is 0.647 m.The seismic performance of the novel MCL suspension bridge meets the specified design requirements,as it remains in the elastic working stage without material yielding or stiffness degradation.The PGA of seismic ground motion has a profound influence,with the structural response of the bridge tower and girder increasing linearly as PGA increases.An increase in PGA from 0.1 g to 0.35 g results in a 5.6%increase in the maximum longitudinal displacement at the tower top,a 21.8%increase in the maximum bending moment at the tower base,a 68.7%increase in the maximum longitudinal displacement at the girder free end,and a 0.6%increase in the maximum vertical displacement at the girder mid-span.Furthermore,the longitudinal position of ground-anchored rods was also found to be critical,with the structural responses of the bridge tower and girder exhibiting a nonlinear relationship with the longitudinal distance between the ground-anchored rods and the rotating saddle.The optimal longitudinal position of the ground-anchored rods is found to be as close as possible to the rotating saddle.These findings elucidate the seismic behavior mechanisms and provide critical quantitative guidance for the seismic design of MCL suspension bridges. 展开更多
关键词 MCL suspension bridge earthquake action ground-anchored rods finite element transient analysis seismic responses
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Sensitivity analysis of vibration characteristics and dynamic responses of a tracked vehicle
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作者 Xun Wang Xue Rui +3 位作者 Jinghong Wang Xiaoting Rui Guoping Wang Pingxin Wang 《Defence Technology(防务技术)》 2026年第3期323-348,共26页
This study aims to establish an integrated sensitivity analysis framework for optimization and design of the dynamic performance of mechanical systems such as tracked vehicles,by combining the direct differentiation m... This study aims to establish an integrated sensitivity analysis framework for optimization and design of the dynamic performance of mechanical systems such as tracked vehicles,by combining the direct differentiation method(DDM)with the linear multibody system transfer matrix method(linear MSTMM).The rigid-flexible coupled multibody system dynamics model of a tracked vehicle is established using the linear MSTMM and validated through the modal test.Building upon the existing DDM-based eigenvalue sensitivity analysis method within the linear MSTMM,the DDM is embedded into it to enable programmable and efficient computation of dynamic response sensitivities for mechanical systems.The proposed approach is used to quantitatively evaluate the sensitivities of both natural vibration characteristics(e.g.,natural frequencies and mode shapes)and transient dynamic responses of the tracked vehicle with respect to system parameters,successfully identifying critical structural parameters.Compared to conventional finite difference methods,the developed methodology eliminates sensitivity to perturbation step sizes.The contributions of this work lie in establishing a unified theoretical foundation and analysis framework for guiding dynamics optimization and design of mechanical systems,and extending the applicability of the linear MSTMM to sensitivity analysis of transient dynamic responses. 展开更多
关键词 Tracked vehicle Sensitivity analysis Vibration characteristics Dynamic responses Direct differentiation method Linear multibody system transfer matrix method
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Dynamic responses of Dagangshan high-arch dam under Luding earthquake:Insights from microseismic monitoring and digital twin model
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作者 Ke Ma Yusheng Tang +2 位作者 Fuqiang Ren Zhaohu Yuan Zhiliang Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期986-1001,共16页
The integration of digital twin(DT)technology with microseismic(MS)monitoring for evaluating the dynamic response of high-arch dams remains under-explored.This paper investigates the application of MS monitoring on th... The integration of digital twin(DT)technology with microseismic(MS)monitoring for evaluating the dynamic response of high-arch dams remains under-explored.This paper investigates the application of MS monitoring on the Dagangshan high-arch dam during its normal water storage operating period to assess potential damage.The study analyzes the MS characteristics of the dam during the Luding earthquake(Ms=6.8).A framework for constructing a damage driven DT model of a high-arch dam is proposed.The DT model is capable of self-updating its mechanical parameters based on MS data.Seismic response calculations are conducted utilizing cloud computing,allowing for the direct presentation of results within the DT model.The results indicate a high-risk area of the Dagangshan arch dam,characterized by significantMS deformation,primarily centered on the arch crown beam.This zone encompasses dam sections Nos.5-6,10-11,13-16,and 19-20,all located above 1030 m elevation.Under seismic loading,the arch dam exhibits a back-and-forth movement along the river,ultimately reaching a stable state.Following the earthquake,the stress state of the dam does not experience substantial changes.The average relative error between numerical results and measured peak ground acceleration values is 17%when considering the cumulative effect of damage,compared to 36%when neglecting this effect.This study presents a more reliable approach for assessing the state of dams. 展开更多
关键词 High-arch dam Dynamic responses Microseismic(MS)monitoring Digital twins(DTs) Luding earthquake
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WRKY53:A Key Player in Stress Responses and Growth Regulation in Rice
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作者 AN Shuaizu LÜJun +4 位作者 MA Zemin GAO Xuanlin ZHANG Biaoming YANG Pingfang KE Yinggen 《Rice science》 2026年第1期30-38,共9页
As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a ... As sessile organisms,plants must adapt various stresses.Accordingly,they have evolved several plant-specific growth and developmental processes.WRKY53 is a member of the WRKY transcription factor family,which plays a crucial role in rice growth and development,stress response,and hormone signal transduction.This review discusses the role of WRKY53 in stress response,focusing on its functions in cold tolerance,salt tolerance,disease resistance,and pest defense,and explores its role in regulating rice leaf senescence and seed germination.This article also proposes future research directions,including functional genomics studies,protein interaction network analyses,hormone signal transduction pathways,genetic improvement strategies,applications of gene editing technologies,molecular basis of stress responses,cross-species functional conservation,and bioinformatics and comparative genomics research.This review highlights the importance of WRKY53 in rice biology and provides new perspectives and strategies for future research and genetic improvement of rice. 展开更多
关键词 WRKY53 RICE stress response signal transduction growth and development genetic improvement
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Analysis of the Impact of Evidence-Based Nursing on Postoperative Complications and Stress Responses in Patients with Ureteral Calculi Undergoing Holmium Laser Lithotripsy
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作者 Yanying Huang 《Journal of Clinical and Nursing Research》 2026年第2期236-242,共7页
Objective:To explore the application effect of evidence-based nursing in the postoperative care of patients with ureteral calculi undergoing holmium laser lithotripsy,analyze its impact on the incidence of postoperati... Objective:To explore the application effect of evidence-based nursing in the postoperative care of patients with ureteral calculi undergoing holmium laser lithotripsy,analyze its impact on the incidence of postoperative complications,the degree of stress response,and nursing satisfaction,and provide evidence-based support for optimizing clinical nursing practices.Methods:A total of 100 patients with ureteral calculi who underwent holmium laser lithotripsy in our hospital from January 2023 to June 2025 were selected and divided into an observation group(50 cases)and a control group(50 cases)using a random number table method.The control group received routine nursing interventions,while the observation group adopted an evidence-based nursing model.The incidence of postoperative complications(hematuria,urinary tract infection,renal colic,ureteral stricture),stress response indicators(heart rate,systolic blood pressure,diastolic blood pressure,Self-Rating Anxiety Scale(SAS)score,Self-Rating Depression Scale(SDS)score)before surgery and 24 hours after surgery,and nursing satisfaction were compared between the two groups.Results:The total incidence of postoperative complications in the observation group was significantly lower than that in the control group(p<0.05).At 24 hours after surgery,the heart rate,systolic blood pressure,diastolic blood pressure,SAS score,and SDS score in the observation group were significantly lower than those in the control group(all p<0.01).Nursing satisfaction in the observation group was significantly higher than that in the control group(p<0.01).Conclusion:Evidence-based nursing can effectively reduce the incidence of postoperative complications in patients with ureteral calculi undergoing holmium laser lithotripsy,alleviate patients’stress responses,and improve nursing satisfaction,demonstrating significant clinical application value. 展开更多
关键词 Evidence-based nursing Ureteral calculi Holmium laser lithotripsy COMPLICATIONS Stress response Nursing satisfaction
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Tissue-Specific Transcriptomic Responses and Viral Accumulation in Lily Cultivars Infected with Cucumber Mosaic Virus
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作者 Yun-Im Kang Youn Jung Choi +3 位作者 Su Young Lee Young-Ran Lee Ki-Byung Lim Yun-Jae Ahn 《Phyton-International Journal of Experimental Botany》 2026年第1期103-118,共16页
Cucumber mosaic virus(CMV)threatens lily production by reducing floral quality and enabling carry-over via infected planting stock.To explore tissue-specific host responses,we analyzed a legacy,single-replicate RNA-se... Cucumber mosaic virus(CMV)threatens lily production by reducing floral quality and enabling carry-over via infected planting stock.To explore tissue-specific host responses,we analyzed a legacy,single-replicate RNA-seq dataset from two cultivars,‘Cancun’and‘Connecticut King’(CK),profiling leaf(source)and bulb(sink)tissues at 0 and 28 days post-inoculation(dpi),alongside leaf DAS-ELISA.Principal component analysis indicated that tissue identity dominated the transcriptome(PC1=47.7%),with CMV treatment driving within-tissue shifts over time.Exploratory Gene Ontology/KEGG summaries and a focused marker panel revealed a consistent split:in leaves,genes linked to jasmonate/WRKY-associated defense(e.g.,WRKY40/41/51/53;AOS/OPR1/2;CYP74A/DDE2)tended to show higher expression at 28 dpi,whereas cell-wall/transport-related terms were reduced;in bulbs,transcripts associated with photosynthetic/organellar maintenance(LHCB/CAB,HCF107)andβ-amylase-linked carbohydrate turnover were more prominent,with comparatively limited elevation of canonical defense modules.Leaf ELISA trajectories were compatible with this framework:CK showed a transient peak at 14 dpi followed by a decline at 24 dpi,whereas‘Cancun’increased progressively.Taken together,the concordance among ordination,enrichment patterns,marker behavior,and leaf titers in this non-replicated dataset is consistent with a working model in which stronger or earlier leaf responses may contribute to partial containment and reduced systemic accumulation.We propose a compact leaf marker set(WRKY40/41/51/53;AOS/OPR1/2;CYP74A/DDE2)and bulb candidates(β-amylase;LHCB/CAB/HCF107)as hypothesis-generating indicators of containment and sink maintenance.These tissue-resolved patterns provide a descriptive framework and a starting point for future validation by qPCR and replicated RNA-seq across additional cultivars,with the long-term goal of informing selection and stock hygiene in lily production. 展开更多
关键词 Ornamental geophytes tissue-specific response jasmonate/WRKY SOURCE-SINK breeding markers plant-virus interaction
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Generalized semi-analytical modeling of three-dimensional contact responses in piezoelectric semiconductors with conductive indenters
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作者 Ling WANG Huoming SHEN Yuxing WANG 《Applied Mathematics and Mechanics(English Edition)》 2026年第3期555-572,共18页
Piezoelectric semiconductor(PSC)materials exhibit strong electromechanical coupling affected by free carriers,which makes their contact behavior essential for sensors,actuators,and electronic devices.Analytical models... Piezoelectric semiconductor(PSC)materials exhibit strong electromechanical coupling affected by free carriers,which makes their contact behavior essential for sensors,actuators,and electronic devices.Analytical models for three-dimensional(3D)PSC contact problems are still scarce,especially for conductive indenters.This work develops a semi-analytical framework to study the 3D frictionless contact between a conductive indenter and a PSC half-space.Fundamental solutions under a unit force and a unit electric charge are derived,and the corresponding frequency response functions are combined with a discrete convolution-fast Fourier transform(DC-FFT)algorithm to achieve an efficient semi-analytical contact model.The numerical results demonstrate that an increase in the surface charge density reduces the indentation pressure and modifies the electric potential distribution.A higher steady carrier concentration enhances the screening effect,suppresses the electromechanical coupling,and shifts the system response toward purely elastic behaviors.The sensitivity analysis shows that the indentation depth is dominated by the elastic constants,while the electric potential is mainly affected by the piezoelectric coefficient.Although the analysis is carried out with spherical indenters,the model is not limited to a specific indenter shape.It provides an effective tool for investigating complex 3D PSC contact problems and offers useful insights into the design of PSC materials-based devices. 展开更多
关键词 contact mechanics semi-analytical method piezoelectric semiconductor(PSC) conductive indenter electromechanical response
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Metal(loid)accumulation and foliar physiological responses in Oryza sativa L.induced by PM1 exposure from various emission sources
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作者 Meixuan Fang Yue Yang +4 位作者 Baofeng Zhang Yingluo Chen Jingdong Mao Liping Lou Qi Lin 《Journal of Environmental Sciences》 2026年第1期585-595,共11页
Foliar uptake of airborne metal(loid)s plays a crucial role in metal(loid)accumulation in plant organs and is influ-enced by the size and emission sources of aerosols.Given the high enrichment of toxic metal(loid)s in... Foliar uptake of airborne metal(loid)s plays a crucial role in metal(loid)accumulation in plant organs and is influ-enced by the size and emission sources of aerosols.Given the high enrichment of toxic metal(loid)s in submicron-scale particulates(PM1),this study established a PM1 exposure system to examine airborne metal(loid)accu-mulation and foliar physiological responses in Oryza sativa L.The results showed that the concentrations of Cu,Zn,As,Pb,and Cd in the leaves and grains were influenced not only by the airborne metal(loid)levels but also by the specific nature of the PM1 particles.The quantitative model for PM1-associated Pb entry into leaf tissue indicated that foliar Pb accumulation was primarily driven by particle adhesion,followed by hydrophilic pene-tration and trans-stomatal liquid film migration,accounting for 87%–89%of the total accumulation.The strong hygroscopicity and high Pb activity of PM1 emitted from waste incineration(WI)increased the Pb absorption coefficient via the hydrophilic and liquid film migration pathway.In contrast,the high hydrophobicity of PM1 from coal burning(CB)led to greater retention of Pb on leaf surfaces.Both foliar reactive oxygen metabolism and photosynthesis indices were sensitive to air pollution.Foliar metal(loid)accumulation and airborne PM1 concentration accounted for the variance in physiological responses in rice leaves.Our results also indicated that Pb was the key element in PM1 emissions from both coal burning(CB)and waste incineration(WI)responsible for significant physiological changes in rice leaves. 展开更多
关键词 Metal(loid) PM1 exposure Coal burning Waste incineration Physiological response Particle nature
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Analytical solution for longitudinal responses of tunnels under combined effects of seismic waves and strike-slip faulting
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作者 Jie Tang Manchao He +2 位作者 Yafei Qiao Hanbing Bian Chun Zhu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1266-1289,共24页
Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analyt... Strong seismic excitation and fault dislocation are likely to occur simultaneously in high-intensity seismic zones,causing severe damage to tunnels crossing active fault zones.This paper aims to develop a novel analytical solution to determine the longitudinal mechanical responses of tunnels subjected to the combined effects of seismic waves and strike-slip faulting.Adopting the elastic springbeam model,the seismic waves are modelled as shear horizontal(SH)waves and the fault dislocation follows an S-shaped pattern;the superposition principle for free-fielddisplacements caused by both effects is assumed.In addition,the transmission and reflectionof seismic waves at the fault-rock geological interface and the tangential contact conditions at the tunnel-rock interface are considered.The analytical model is validated against numerical simulations,confirmingits accuracy in calculating tunnel responses.Moreover,a parametric study is conducted to evaluate the impact of key factors,including fault displacement,fault zone width,fault dip angle,earthquake frequency,rock conditions,tunnel lining stiffness,and tangential contact conditions,on tunnel responses.Compared with each effect alone,the combined effects of seismic waves and strike-slip faulting significantlychange the tunnel deformation and internal forces,leading to increased tunnel responses,especially within the fault zone and near the fault-rock interfaces.Depending on specificparameters,tunnel responses can be classifiedinto seismic-dominated,faulting-dominated,and seismic-faulting coupled responses on the basis of the relative contributions of each effect.The proposed analytical solution can be applied to quickly predict the longitudinal mechanical behaviour of tunnels under such combined effects in engineering applications. 展开更多
关键词 Strike-slip faulting Longitudinal tunnel response Analytical solution Seismic waves Wave transmissions and reflections
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Spinal cord injury-derived exosomes exacerbate damage:miR-155-5p mediates inflammatory responses
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作者 Yuming Fang Weican Chen +6 位作者 Yan Zhang Yushen Yang Shengnan Wang Mengqin Pei Yilin Zhou Shu Lin Hefan He 《Neural Regeneration Research》 2026年第6期2514-2522,共9页
Spinal cord injury is a critical event characterized by intricate pathogenic mechanisms.Although recent studies have highlighted tissue exosomes as key mediators of inflammatory responses in diverse organs and tissues... Spinal cord injury is a critical event characterized by intricate pathogenic mechanisms.Although recent studies have highlighted tissue exosomes as key mediators of inflammatory responses in diverse organs and tissues,their role in spinal cord injury has yet to be determined.In this study,we investigated the role and mechanisms of spinal cord tissue exosomes in the inflammatory response following spinal cord injury.We found morphological,concentration,and functional differences between exosomes extracted from injured and normal spinal cord tissues,and identified proinflammatory effects associated with spinal cord injury-generated tissue exosomes but not with exosomes derived from normal spinal cord tissue.Our in vivo and in vitro analyses showed that spinal cord injury-generated tissue exosomes promoted microglial M1 polarization and inflammatory cytokine expression,thereby exacerbating tissue and neuronal injury in the spinal cord.In addition,the combination of exosomal miRNA sequencing and experimental verification showed that the miR-155-5p level was higher in spinal cord injury-generated tissue exosomes than in spinal cord tissue.We further found that spinal cord injury-generated tissue exosomes-derived miR-155-5p induced a significant inhibition of forkhead box O3a phosphorylation and activated the nuclear factor-kappa B pathway,thereby promoting microglial M1 polarization and inflammatory cytokine expression.These findings suggest that injury-induced miR-155-5p-containing exosomes exacerbate spinal cord injury via the promotion of microglial M1 polarization and inflammatory responses.Thus,targeting miR-155-5p expression or exosome secretion could be a novel strategy for attenuating inflammation and reducing secondary injury post-spinal cord injury. 展开更多
关键词 EXOSOMES FOXO3A inflammatory response MICROGLIA miR-155-5p NEURON nuclear factor-kappa B spinal cord injury spinal cord injury-generated tissue exosomes
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Bifidobacteria support optimal infant vaccine responses
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作者 Feargal J Ryan 《四川生理科学杂志》 2025年第4期753-753,共1页
Accumulating evidence indicates that antibiotic exposure may lead to impaired vaccine responses1-4;however,the mechanisms underlying this association remain poorly understood.Here we prospectively followed 191 healthy... Accumulating evidence indicates that antibiotic exposure may lead to impaired vaccine responses1-4;however,the mechanisms underlying this association remain poorly understood.Here we prospectively followed 191 healthy,vaginally born,term infants from birth to 15 months,using a systems vaccinology approach to assess the effects of antibiotic exposure on immune responses to vaccination.Exposure to direct neonatal but not intrapartum antibiotics was associated with significantly lower antibody titres against various polysaccharides in the 13-valent pneumococcal conjugate vaccine and the Haemophilus influenzae type b polyribosylribitol phosphate and diphtheria toxoid antigens in the combined 6-in-1 Infanrix Hexa vaccine at 7 months of age.Blood from infants exposed to neonatal antibiotics had an inflammatory transcriptional profile before vaccination;in addition,faecal metagenomics showed reduced abundance of Bifidobacterium species in these infants at the time of vaccination,which was correlated with reduced vaccine antibody titres 6 months later.In preclinical models,responses to the 13-valent pneumococcal conjugate vaccine were strongly dependent on an intact microbiota but could be restored in germ-free mice by administering a consortium of Bifidobacterium species or a probiotic already widely used in neonatal units.Our data suggest that microbiota-targeted interventions could mitigate the detrimental effects of early-life antibiotics on vaccine immunogenicity. 展开更多
关键词 vaccine responses antibody titres BIFIDOBACTERIA MICROBIOTA ANTIBIOTICS infant immunology immune responses systems vaccinology approach
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Smart Core-Shell Elastomer Fibers with Simultaneous Resistance and Color Responses
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作者 Dong-Peng Sun Yao Xiao +3 位作者 Yuan Zheng An-Xun Zhang Bao-Ling Guo Dong Chen 《Chinese Journal of Polymer Science》 2025年第4期556-562,共7页
Fibers with deformation-triggered responses are essential for smart textiles and wearable electronics.Here,smart core-shell elastomer fibers with a conductive core and a liquid crystal elastomer shell showing simultan... Fibers with deformation-triggered responses are essential for smart textiles and wearable electronics.Here,smart core-shell elastomer fibers with a conductive core and a liquid crystal elastomer shell showing simultaneous resistance and color responses are designed and prepared.The conductive core is consisted of interconnected liquid metal nanodroplets dispersed in a polymer matrix and the elastomer shell is made of cholesteric liquid crystals.When stretched,the fiber resistance increases as the interconnected pathways of liquid metal nanodroplets along the fiber axis become narrower,and the selective reflection color from the fiber surface blueshifts since the cholesteric pitch decreases.The smart elastomer fibers could be woven into smart textiles and respond to various mechanical deformations,including stretching,bending,compression and twisting.The average resistance change is 51%under 100%strain and its variation is smaller than 4%over 500 cycles,showing remarkable fatigue resistance.The simultaneous resistance and color responses to mechanical deformations make the fibers attractive for broad applications,such as flexible electronics. 展开更多
关键词 Elastomer fiber CORE-SHELL Simultaneous responses RESISTANCE COLOR
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Floods:Dangers and responses
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作者 叶丹 《疯狂英语(新悦读)》 2025年第10期12-14,76,共4页
Being caught in a flood is incredibly dangerous.Like many other natural disasters,floods can occur with little or no warning.Flash floods move quickly and have strong currents.They are known to rip(扯)trees out of the... Being caught in a flood is incredibly dangerous.Like many other natural disasters,floods can occur with little or no warning.Flash floods move quickly and have strong currents.They are known to rip(扯)trees out of the ground,destroy buildings and cause bridges to collapse. 展开更多
关键词 floods responses DANGER flash floods
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Effects of Ozone Exposure on Cardiopulmonary Function and Adaptive Responses in Han and Tibetan Children during Physical Activity at High Altitudes
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作者 Mengyao Bian Ling Qi +2 位作者 Qian Guo Yuchen Zhao Xiaoli Duan 《Biomedical and Environmental Sciences》 2025年第5期633-638,共6页
The cardiopulmonary health of children may be affected by acute ozone(O3)exposure during physical activity[1];however,its effects in high-altitude regions such as the Xizang Plateau remain uncertain.In high-altitude a... The cardiopulmonary health of children may be affected by acute ozone(O3)exposure during physical activity[1];however,its effects in high-altitude regions such as the Xizang Plateau remain uncertain.In high-altitude areas,lower oxygen levels may cause children to experience shortness of breath or require increased respiratory effort during vigorous activities such as running.This could lead to increased pollutant inhalation,potentially elevating the burden on the cardiovascular system and triggering adverse reactions such as increased heart rate and elevated blood pressure.Furthermore,differences in physiological adaptation between Han children who have migrated to Xizang and Tibetan children who are native to the region may contribute to different reactions to environmental exposure[2]. 展开更多
关键词 cardiopulmonary health cardiopulmonary function cardiovascular system shortness breath pollutant inhalationpotentially Tibetan children adaptive responses ozone exposure
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High-fat intake induces gut microbiota disorders,inflammatory responses and oxidative stress in Nyctereutes procyonoides
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作者 Zhaoming Li Chengwei Wei +4 位作者 Jie Yang Yuan Geng Mengran Zhu Tianchao Xu Mengyao Guo 《Animal Diseases》 2025年第1期17-32,共16页
The Nyctereutes procyonoides is highly regarded in the farming and leather industries because of the high value of its fur,which renders artificial feeding a crucial aspect.However,high-fat diets have always been asso... The Nyctereutes procyonoides is highly regarded in the farming and leather industries because of the high value of its fur,which renders artificial feeding a crucial aspect.However,high-fat diets have always been associated with a variety of digestive disorders.This study aimed to investigate the impact of high-fat diets on the gut microbiota and the mechanisms of gut damage in Nyctereutes procyonoides.16S rRNA sequencing demonstrated that high-fat diets caused diarrhea and intestinal damage through alterations in the gut microbiota:a decrease in the abundance of Firmicutes,an increase in the abundance of Proteobacteria and Actinobacteria,and an increase in the abundance of Enterococcaceae,Escherichia coli-Shigella,Clostridium and Lactobacillus.Subsequently,changes in metabolic path-ways,such as amino and fatty acid pathways,were identified by KEGG and COG enrichment analysis,and the TLR4/NF-κB/NLRP3 inflammatory signaling pathway was shown to be activated by high-fat diets.In addition,high-fat diets lead to the accumulation of ROS and MDA and reduce the activity of the antioxidant enzymes GSH-PX and SOD.C orrespondingly,the levels of proinflammatory cytokines(IL-6,IL-1βand TNF-α)were significantly increased,and the apoptosis and necrosis signaling pathways of colonic cells were detected,causing a dramatic decrease in the expression of intestinal tight junction proteins(Occludin,E-cadherin,ZO-1 and ZO-2).In conclusion,high-fat diets altered the structure of the Nyctereutes procyonoides gut microbiota community and led to colon damage.This study provides new insights into the intestinal health of Nyctereutes procyonoides. 展开更多
关键词 Nyctereutes procyonoides High-fat diets Gut microbiota Inflammatory responses Oxidative stress Intestinal barrier
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Braided NiTi alloys microfilaments with near-linear responses:Toward flexible high-pressure sensors
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作者 Yiwen Liu Ling Li +8 位作者 Fei Xiao Ruihang Hou Zehuan Lin Xiaorong Cai Shungui Zuo Ying Zhou Shuyuan Hua Yuhan Chen Xuejun Jin 《Journal of Materials Science & Technology》 2025年第26期269-278,共10页
Shape memory alloys(SMAs)are smart materials with superelasticity originating from a reversible stressinduced martensitic transformation(MT)accompanied by a significant electrical resistance change.However,the stress-... Shape memory alloys(SMAs)are smart materials with superelasticity originating from a reversible stressinduced martensitic transformation(MT)accompanied by a significant electrical resistance change.However,the stress-strain and resistance-stress relationships of typical NiTi wires are non-linear due to the stress plateau during the stress-induced MT.This limits the usage of these materials as pressure sensors.Herein,we propose a high-strength flexible sensor based on superelastic NiTi wires that achieves near-linear mechanical and electrical responses through a low-cost double-braided strategy.This microarchitectured strategy reduces or even eliminates stress plateau and it is demonstrated that the phase transformation of microfilaments can be controlled:regions with localized stress undergo the MT first,which is successively followed by the rest of the microfilament.This structure-dependent MT characteristic exhibits slim-hysteresis superelasticity and tunable low stiffness,and the braided wire shows improved flexibility.The double-braided NiTi microfilaments exhibit stable electrical properties and repeatability under approximately 600 MPa(8%strain)and can maintain stability over a wide temperature range(303-403 K).Moreover,a cross-grid flexible woven sensor array textile based on microfilaments is further developed to detect pressure distribution.This work provides insight into the design and application of SMAs in the field of flexible and functional fiber. 展开更多
关键词 NITI Shape memory alloys BRAIDING Near-linear responses Flexible pressure sensors
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Biogeochemical responses to the dynamic processes associated with the Equatorial Undercurrent in the tropical eastern Indian Ocean during April-May
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作者 Qinsheng Wei Huiwu Wang +7 位作者 Yongliang Duan Junchuan Sun Teguh Agustiadi Xiaomeng Duan Yawen Zou Lin Liu Baodong Wang Weidong Yu 《Acta Oceanologica Sinica》 2025年第12期56-68,共13页
The unique features of the Equatorial Undercurrent(EUC)and relations to the Indian Ocean Dipole(IOD)highlight the complexity and importance of the tropical eastern Indian Ocean(EIO),yet the EUC dynamics and associated... The unique features of the Equatorial Undercurrent(EUC)and relations to the Indian Ocean Dipole(IOD)highlight the complexity and importance of the tropical eastern Indian Ocean(EIO),yet the EUC dynamics and associated physical-biogeochemical implications remain patchy.Here,mainly using in situ observations during April-May 2011,we provide direct evidence of the spring eastward EUC and its relations to the southward subsurface salty water and upwelling off Sumatra and reveal its biogeochemical responses.A strong eastward velocity of~1.2 m/s at a depth of 120 m near the equator along the meridional section of 90°E clearly indicates the EUC.The continuum of subsurface salty water from the equator to the offshore region off Sumatra generally shows the pathway and dynamic bridge role of the EUC.The southward shoaling of isotherms and isohalines near the upper boundary of thermocline in the region off Sumatra implies the occurrence of weak upwelling from the subsurface salty water;the early onset of southeasterly wind associated with the positive IOD might be responsible for this phenomenon.The EUC is important in driving the spatial variability of the oxygen minimum zone(OMZ)and subsurface chlorophyll a maximum(SCM)in the tropical EIO.In particular,the EUC may act as a source of O_(2),depressing the upward limit of the OMZ at the equator.Moreover,the eastward depressed EUC induces the downwelling of the OMZ and a deepened and weakened SCM from west to east along the equator.Influenced by EUC transport and upwelling,a southward extension of the OMZ with an uplifted oxycline occurred in the region off Sumatra,and a southward enhanced and shoaled SCM emerged.The results unraveled the dynamic linkages between the EUC and biogeochemical environments,constituting a considerable contribution to the understanding of the physical-biogeochemical-ecological interactions in the tropical EIO. 展开更多
关键词 Equatorial Undercurrent biogeochemical responses oxygen minimum zone subsurface chlorophyll a maximum UPWELLING eastern Indian Ocean
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Coupling Magneto-Electro-Elastic Multiscale Finite Element Method for Transient Responses of Heterogeneous MEE Structures
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作者 Xiaolin Li Xinyue Li +2 位作者 Liming Zhou Hangran Yang Xiaoqing Yuan 《Computers, Materials & Continua》 2025年第3期3821-3841,共21页
Magneto-electro-elastic(MEE)materials are widely utilized across various fields due to their multi-field coupling effects.Consequently,investigating the coupling behavior of MEE composite materials is of significant i... Magneto-electro-elastic(MEE)materials are widely utilized across various fields due to their multi-field coupling effects.Consequently,investigating the coupling behavior of MEE composite materials is of significant importance.The traditional finite element method(FEM)remains one of the primary approaches for addressing such issues.However,the application of FEM typically necessitates the use of a fine finite element mesh to accurately capture the heterogeneous properties of the materials and meet the required computational precision,which inevitably leads to a reduction in computational efficiency.To enhance the computational accuracy and efficiency of the FEM for heterogeneous multi-field coupling problems,this study presents the coupling magneto-electro-elastic multiscale finite element method(CM-MsFEM)for heterogeneous MEE structures.Unlike the conventional multiscale FEM(MsFEM),the proposed algorithm simultaneously constructs displacement,electric,and magnetic potential multiscale basis functions to address the heterogeneity of the corresponding parameters.The macroscale formulation of CM-MsFEM was derived,and the macroscale/microscale responses of the problems were obtained through up/downscaling calculations.Evaluation using numerical examples analyzing the transient behavior of heterogeneous MEE structures demonstrated that the proposed method outperforms traditional FEM in terms of both accuracy and computational efficiency,making it an appropriate choice for numerically modeling the dynamics of heterogeneous MEE structures. 展开更多
关键词 Multiscale finite element method heterogeneous materials transient responses MAGNETO-ELECTRO-ELASTIC multiscale basis function
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