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Genome-Wide Exploration of the Grape GLR Gene Family and Differential Responses of VvGLR3.1 and VvGLR3.2 to Low Temperature and Salt Stress
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作者 Honghui Sun Ruichao Liu +6 位作者 Yueting Qi Hongsheng Gao Xueting Wang Ning Jiang Xiaotong Guo Hongxia Zhang Chunyan Yu 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第3期533-549,共17页
Grapes,one of the oldest tree species globally,are rich in vitamins.However,environmental conditions such as low temperature and soil salinization significantly affect grape yield and quality.The glutamate receptor(GLR... Grapes,one of the oldest tree species globally,are rich in vitamins.However,environmental conditions such as low temperature and soil salinization significantly affect grape yield and quality.The glutamate receptor(GLR)family,comprising highly conserved ligand-gated ion channels,regulates plant growth and development in response to stress.In this study,11 members of the VvGLR gene family in grapes were identified using whole-genome sequence analysis.Bioinformatic methods were employed to analyze the basic physical and chemical properties,phylogenetic trees,conserved domains,motifs,expression patterns,and evolutionary relationships.Phylogenetic and collinear analyses revealed that the VvGLRs were divided into three subgroups,showing the high conservation of the grape GLR family.These members exhibited 2 glutamate receptor binding regions(GABAb and GluR)and 3-4 transmembrane regions(M1,M2,M3,and M4).Real-time quantitative PCR analysis demonstrated the sensitivity of all VvGLRs to low temperature and salt stress.Subsequent localization studies in Nicotiana tabacum verified that VvGLR3.1 and VvGLR3.2 proteins were located on the cell membrane and cell nucleus.Additionally,yeast transformation experiments confirmed the functionality of VvGLR3.1 and VvGLR3.2 in response to low temperature and salt stress.Thesefindings highlight the significant role of the GLR family,a highly conserved group of ion channels,in enhancing grape stress resistance.This study offers new insights into the grape GLR gene family,providing fundamental knowledge for further functional analysis and breeding of stress-resistant grapevines. 展开更多
关键词 Genome-wide identification glutamate receptor(GLR)family low temperature stress salt stress GRAPE
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Calculation of Mass Concrete Temperature and Creep Stress under the Influence of Local Air Heat Transfer
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作者 Heng Zhang Chao Su +2 位作者 Xiaohu Chen Zhizhong Song Weijie Zhan 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第9期2977-3000,共24页
Temperature-induced cracking during the construction of mass concrete is a significant concern.Numerical simulations of concrete temperature have primarily assumed that the concrete is placed in an open environment.Th... Temperature-induced cracking during the construction of mass concrete is a significant concern.Numerical simulations of concrete temperature have primarily assumed that the concrete is placed in an open environment.The problem of heat transfer between the air and concrete has been simplified to the concrete’s heat dissipation boundary.However,in the case of tubular concrete structures,where air inlet and outlet are relatively limited,the internal air temperature does not dissipate promptly to the external environment as it rises.To accurately simulate the temperature and creep stress in tubular concrete structures with enclosed air spaces during construction,we establish an air–concrete coupled heat transfer model according to the principles of conjugate heat transfer,and the accuracy of the model is verified through experiments.Furthermore,we conduct a case study to analyze the impact of airflow within the ship lock corridor on concrete temperature and creep stress.The results demonstrate that enhancing airflow within the corridor can significantly reduce the maximum concrete temperature.Compared with cases in which airflow within the corridor is neglected,the maximum concrete temperature and maximum tensile stress can be reduced by 12.5°C and 0.7 MPa,respectively,under a wind speed of 4 m/s.The results of the traditional calculation method are relatively close to those obtained at a wind speed of 1 m/s.However,the temperature reduction process in the traditional method is faster,and the method yields greater tensile stress values for the corridor location. 展开更多
关键词 Conjugate heat transfer temperature field mass concrete creep stress
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Resistance index and browning mechanism of apple peel under high temperature stress
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作者 Hui Wang Shuhui Zhang +8 位作者 Zidun Wang Dongmei Li Leiyu Yan Yifeng Feng Xiaojie Liu Rongxin Chen Wenmin Fan Lulong Sun Zhengyang Zhao 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期305-317,共13页
Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect no... Apples are one of the most important economic crops worldwide.Because of global warming and an aggravation of environmental,abnormally high temperatures occur frequently in fruit-growing season and seriously affect normal fruit growth and reduce fruit quality and yield.We took five-year-old Ruixue’(Qinfu 1×Pink Lady;CNA20151469.1) fruits as test materials,and the ambient temperature during fruit development was monitored.The results showed that during the fruit-growing season,especially during the rapid growth stage (July to August),the maximum daily temperature exceeded 30℃ and lasted for more than 40 days.To determine the effects of high temperature stress on the apple fruit resistance,we treated expanding,veraison,and maturity-period fruits at different temperatures.It was found that the fruits of the expanding period showed strong resistance to high temperature stress,whereas during veraison and maturity,fruit resistance to high temperature stress decreased,and the fruit peel browning phenotype appeared.Meanwhile,the content of malonaldehyde (MDA),hydrogen peroxide (H_(2)O_(2)),and superoxide anion (O._(2)^(-)) in the peel gradually increased with increasing temperature.The content of total phenols,flavanol,and flavonoids in the peel decreased substantially at 45℃.Moreover,it was found that polyphenol oxidase gene (MdPPO1) was most sensitive to high temperature stress in apple.Furthermore,transient and stable MdPPO1 overexpression significantly promoted peel browning.The transgenic materials were more sensitive to high temperatures,and browning was more severe compared to non-genetically modified organism (WT).Stable MdPPO1 knockout calli obtained via clustered regularly interspersed short palindromic repeats (CRISPR/Cas9) gene knockout technology reduced the browning phenotype,and the resultant fruits were not sensitive to the effects of high temperature stress.Thus,MdPPO1 expression may be a key factor of high temperature-related changes observed in the browning phenotype that provides a scientific theoretical basis for the selection of high temperature-resistant varieties and apple cultivation and management in the future. 展开更多
关键词 Malus domestica Borkh High temperature stress PEEL BROWNING MdPPO1
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Influence of temperature, stress, and grain size on behavior of nano-polycrystalline niobium
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作者 晏玉平 张柳亭 +2 位作者 张丽攀 芦刚 涂志新 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期467-474,共8页
Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS)... Atomic simulations are executed to investigate the creep responses of nano-polycrystalline(NC) niobium established by using the Voronoi algorithm. The effects of varying temperature, applied stress, and grain size(GS) on creep properties and mechanisms are investigated. Notably, the occurrence of tertiary creep is exclusively observed under conditions where the applied stress exceeds 4.5 GPa and the temperature is higher than 1100 K. This phenomenon can be attributed to the significant acceleration of grain boundary and lattice diffusion, driven by the elevated temperature and stress levels. It is found that the strain rate increases with both temperature and stress increasing. However, an interesting trend is observed in which the strain rate decreases as the grain size increases. The stress and temperature are crucial parameters governing the creep behavior. As these factors intensify, the creep mechanism undergoes a sequential transformation: initially from lattice diffusion under low stress and temperature conditions to a mixed mode combining grain boundaries(GBs) and lattice diffusion at moderate stress and mid temperature levels, and ultimately leading to the failure of power-law controlled creep behavior, inclusive of grain boundary recrystallization under high stress and temperature conditions. This comprehensive analysis provides in more detail an understanding of the intricate creep behavior of nano-polycrystalline niobium and its dependence on various physical parameters. 展开更多
关键词 creep behavior molecular dynamics simulation activation energy stress exponent nano-polycrystalline niobium
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Effects of Low Temperature Stress on Germination and Physiological Characteristics of Different Sweet Maize Varieties
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作者 Zhenxing WU Jianjian CHEN +1 位作者 Tingzhen WANG Guihua LU 《Plant Diseases and Pests》 2024年第1期1-3,6,共4页
[Objectives]The paper was to explore the effects of low temperature stress on germination and physiological characteristics of different sweet maize varieties.[Methods]Taking Taitian 264,Zhexuetian 1 and Chaotian 4 as... [Objectives]The paper was to explore the effects of low temperature stress on germination and physiological characteristics of different sweet maize varieties.[Methods]Taking Taitian 264,Zhexuetian 1 and Chaotian 4 as the research objects,the changes in germination potential,germination index,plant height,biomass,and antioxidant enzyme activity of maize seeds were studied under optimal temperature conditions(25℃)and low temperature stress conditions(10℃).[Results]Under 10℃stress,the germination rate and germination index of Taitian 264 were higher than that of Zhexuetian 1 and Chaotian 4.Under low temperature stress,Taitian 264 exhibited the least reduction in height and biomass,while Zhexuetian 1 had the most reduction.Additionally,the SOD and POD activities of Taitian 264 were higher than that of Zhexuetian 1 and Chaotian 4 under both temperature conditions,while the MDA content of Taitian 264 was lower.Taitian 264 showed strong germination ability against low temperature stress.[Conclusions]This study provides a basis for timely sowing practices of sweet maize in agricultural production. 展开更多
关键词 Sweet maize Low temperature stress GERMINATION Antioxidant enzyme
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Advances in Molecular Regulatory Mechanisms of Fruit Trees under Low Temperature Stress
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作者 Huan LIU Lijuan GAO +3 位作者 Minghui JI Longfei LI Jintao XU Baofeng HAO 《Plant Diseases and Pests》 2024年第3期46-48,共3页
The most recent research findings on the tolerance of fruit trees to cold stress are reviewed from a molecular perspective,including the perception and transduction of low temperature calcium signaling,CBF-dependent m... The most recent research findings on the tolerance of fruit trees to cold stress are reviewed from a molecular perspective,including the perception and transduction of low temperature calcium signaling,CBF-dependent molecular regulatory mechanisms,non-CBF-dependent molecular regulatory mechanisms,and so forth.The objective is to provide a reference basis for further improving the cold resistance of fruit trees and cultivating new varieties of hardy plants. 展开更多
关键词 Low temperature stress Fruit trees Growth and development Molecular mechanism Research progress
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Synergistic effects of carbon cycle metabolism and photosynthesis in Chinese cabbage under salt stress 被引量:1
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作者 Hao Liang Qiling Shi +8 位作者 Xing Li Peipei Gao Daling Feng Xiaomeng Zhang Yin Lu Jingsen Yan Shuxing Shen Jianjun Zhao Wei Ma 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第2期461-472,共12页
Chinese cabbage(Brassica rapa ssp. pekinensis) has a long cultivation history and is one of the vegetable crops with the largest cultivation area in China. However, salt stress severely damages photosynthesis and horm... Chinese cabbage(Brassica rapa ssp. pekinensis) has a long cultivation history and is one of the vegetable crops with the largest cultivation area in China. However, salt stress severely damages photosynthesis and hormone metabolism, nutritional balances, and results in ion toxicity in plants. To better understand the mechanisms of salt-induced growth inhibition in Chinese cabbage, RNA-seq and physiological index determination were conducted to explore the impacts of salt stress on carbon cycle metabolism and photosynthesis in Chinese cabbage. Here, we found that the number of thylakoids and grana lamellae and the content of starch granules and chlorophyll in the leaves of Chinese cabbage under salt stress showed a time-dependent response, first increasing and then decreasing. Chinese cabbage increased the transcript levels of genes related to the photosynthetic apparatus and carbon metabolism under salt stress, probably in an attempt to alleviate damage to the photosynthetic system and enhance CO_(2) fixation and energy metabolism. The transcription of genes related to starch and sucrose synthesis and degradation were also enhanced;this might have been an attempt to maintain intracellular osmotic pressure by increasing soluble sugar concentrations. Soluble sugars could also be used as potential reactive oxygen species(ROS) scavengers, in concert with peroxidase(POD)enzymes, to eliminate ROS that accumulate during metabolic processes. Our study characterizes the synergistic response network of carbon metabolism and photosynthesis under salt stress. 展开更多
关键词 Chinese cabbage Salt stress Carbon metabolism PHOTOSYNTHESIS CHLOROPLAST
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Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress
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作者 WEI Huanhe GENG Xiaoyu +7 位作者 ZHANG Xiang ZHU Wang ZHANG Xubin CHEN Yinglong HUO Zhongyang ZHOU Guisheng MENG Tianyao DAI Qigen 《Rice science》 SCIE CSCD 2024年第1期118-128,I0023,共12页
Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinit... Simultaneous stresses of salinity and drought often coincide during rice-growing seasons in saline lands,primarily due to insufficient water resources and inadequate irrigation facilities.Consequently,combined salinity-drought stress poses a major threat to rice production.In this study,two salinity levels(NS,non-salinity;HS,high salinity)along with three drought treatments(CC,control condition;DJ,drought stress imposed at jointing;DH,drought stress imposed at heading)were performed to investigate their combined influences on leaf photosynthetic characteristics,biomass accumulation,and rice yield formation.Salinity,drought,and their combination led to a shortened growth period from heading to maturity,resulting in a reduced overall growth duration.Grain yield was reduced under both salinity and drought stress,with a more substantial reduction under the combined salinity-drought stress.The combined stress imposed at heading caused greater yield losses in rice compared with the stress imposed at jointing.Additionally,the combined salinity-drought stress induced greater decreases in shoot biomass accumulation from heading to maturity,as well as in shoot biomass and nonstructural carbohydrate(NSC)content in the stem at heading and maturity.However,it increased the harvest index and NSC remobilization reserve.Salinity and drought reduced the leaf area index and SPAD value of flag leaves and weakened the leaf photosynthetic characteristics as indicated by lower photosynthetic rates,transpiration rates,and stomatal conductance.These reductions were more pronounced under the combined stress.Salinity,drought,and especially their combination,decreased the activities of ascorbate peroxidase,catalase,and superoxide dismutase,while increasing the contents of malondialdehyde,hydrogen peroxide,and superoxide radical.Our results indicated a more significant yield loss in rice when subjected to combined salinity-drought stress.The individual and combined stresses of salinity and drought diminished antioxidant enzyme activities,inhibited leaf photosynthetic functions,accelerated leaf senescence,and subsequently lowered assimilate accumulation and grain yield. 展开更多
关键词 antioxidant defense system combined salinity-drought stress drought stress photosynthetic characteristics RICE salinity stress
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Three-dimensional stress variation characteristics in deep hard rock of CJPL-Ⅱ project based on in-situ monitoring
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作者 Minzong Zheng Shaojun Li +2 位作者 Zejie Feng Huaisheng Xu Yaxun Xiao 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第2期179-195,共17页
In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensi... In deep hard rock excavation, stress plays a pivotal role in inducing stress-controlled failure. While the impact of excavation-induced stress disturbance on rock failure and tunnel stability has undergone comprehensive examination through laboratory tests and numerical simulations, its validation through insitu stress tests remains unexplored. This study analyzes the three-dimensional stress changes in the surrounding rock at various depths, monitored during the excavation of B2 Lab in China Jinping Underground Laboratory Phase Ⅱ(CJPL-Ⅱ). The investigation delves into the three-dimensional stress variation characteristics in deep hard rock, encompassing stress components and principal stress. The results indicate changes in both the magnitude and direction of the principal stress during tunnel excavation. To quantitatively describe the degree of stress disturbance, a series of stress evaluation indexes are established based on the distances between stress tensors, including the stress disturbance index(SDI), the principal stress magnitude disturbance index(SDIm), and the principal stress direction disturbance index(SDId). The SDI indicates the greatest stress disturbance in the surrounding rock is 4.5 m from the tunnel wall in B2 Lab. SDIm shows that the principal stress magnitude disturbance peaks at2.5 m from the tunnel wall. SDId reveals that the largest change in principal stress direction does not necessarily occur near the tunnel wall but at a specific depth from it. The established relationship between SDI and the depth of the excavation damaged zone(EDZ) can serve as a criterion for determining the depth of the EDZ in deep hard rock engineering. Additionally, it provides a reference for future construction and support considerations. 展开更多
关键词 Disturbance stress Tensor distance stress disturbance index Principal stress direction Underground research laboratory
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Disturbance failure mechanism of highly stressed rock in deep excavation:Current status and prospects
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作者 Tao Wang Weiwei Ye +3 位作者 Liyuan Liu Kai Liu Naisheng Jiang Xianhui Feng 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第4期611-627,共17页
This article reviews the current status on the dynamic behavior of highly stressed rocks under disturbances.Firstly,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stre... This article reviews the current status on the dynamic behavior of highly stressed rocks under disturbances.Firstly,the experimental apparatus,methods,and theories related to the disturbance dynamics of deep,high-stress rock are reviewed,followed by the introduction of scholars’research on deep rock deformation and failure from an energy perspective.Subsequently,with a backdrop of highstress phenomena in deep hard rock,such as rock bursts and core disking,we delve into the current state of research on rock microstructure analysis and residual stresses from the perspective of studying the energy storage mechanisms in rocks.Thereafter,the current state of research on the mechanical response and the energy dissipation of highly stressed rock formations is briefly retrospected.Finally,the insufficient aspects in the current research on the disturbance and failure mechanisms in deep,highly stressed rock formations are summarized,and prospects for future research are provided.This work provides new avenues for the research on the mechanical response and damage-fracture mechanisms of rocks under high-stress conditions. 展开更多
关键词 deep rock with high stress highly stressed rock rock failure residual stress energy release
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Molecular mechanisms of stress resistance in sorghum: Implications for crop improvement strategies
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作者 Hongxiang Zheng Yingying Dang +1 位作者 Xianmin Diao Na Sui 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期741-768,共28页
Abiotic stresses, such as drought, salt, extreme temperatures, and heavy metal pollution, are the main environmental factors that limit crop growth and yield. Sorghum, a C4 grass plant with high photosynthetic efficie... Abiotic stresses, such as drought, salt, extreme temperatures, and heavy metal pollution, are the main environmental factors that limit crop growth and yield. Sorghum, a C4 grass plant with high photosynthetic efficiency, can grow in adverse environmental conditions due to its excellent stress resistance characteristics. Therefore, unraveling the stress-resistance mechanism of sorghum could provide a theoretical basis for developing and cultivating various stress-resistant crops. This understanding could also help to create a conducive environment for using marginal soil in agriculture and ensuring food security. In this review, we discuss the adaptation mechanisms of sorghum under drought, salinity, temperature, and soil heavy metal stresses, the specific response to stress, the screening of sorghum-resistant germplasm, and the identification and functional analysis of the relevant genes and quantitative trait loci(QTL). In addition, we discuss the application potential of different stress-tolerant sorghum germplasms reported to date and emphasize the feasibility and potential use in developing and promoting highly stress-tolerant sorghum in marginal soil. 展开更多
关键词 abiotic stress C4 plants QTL SORGHUM stress resistance yield stability
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Impact of effective stress on permeability for carbonate fractured-vuggy rocks
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作者 Ke Sun Huiqing Liu +5 位作者 Juliana Y.Leung Jing Wang Yabin Feng Renjie Liu Zhijiang Kang Yun Zhang 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第3期942-960,共19页
To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of ef... To gain insight into the flow mechanisms and stress sensitivity for fractured-vuggy reservoirs,several core models with different structural characteristics were designed and fabricated to investigate the impact of effective stress on permeability for carbonate fractured-vuggy rocks(CFVR).It shows that the permeability performance curves under different pore and confining pressures(i.e.altered stress conditions)for the fractured core models and the vuggy core models have similar change patterns.The ranges of permeability variation are significantly wider at high pore pressures,indicating that permeability reduction is the most significant during the early stage of development for fractured-vuggy reservoirs.Since each obtained effective stress coefficient for permeability(ESCP)varies with the changes in confining pressure and pore pressure,the effective stresses for permeability of four representative CFVR show obvious nonlinear characteristics,and the variation ranges of ESCP are all between 0 and 1.Meanwhile,a comprehensive ESCP mathematical model considering triple media,including matrix pores,fractures,and dissolved vugs,was proposed.It is proved theoretically that the ESCP of CFVR generally varies between 0 and 1.Additionally,the regression results showed that the power model ranked highest among the four empirical models mainly applied in stress sensitivity characterization,followed by the logarithmic model,exponential model,and binomial model.The concept of“permeability decline rate”was introduced to better evaluate the stress sensitivity performance for CFVR,in which the one-fracture rock is the strongest,followed by the fracture-vug rock and two-horizontalfracture rock;the through-hole rock is the weakest.In general,this study provides a theoretical basis to guide the design of development and adjustment programs for carbonate fractured-vuggy reservoirs. 展开更多
关键词 Effective stress PERMEABILITY Carbonate fractured-vuggy rocks Structure characteristics stress sensitivity
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Overexpression of the transcription factor MdWRKY115 improves drought and osmotic stress tolerance by directly binding to the MdRD22 promoter in apple
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作者 Qinglong Dong Yi Tian +9 位作者 Xuemei Zhang Dingyue Duan He Zhang Kaiyu Yang Peng Jia Haoan Luan Suping Guo Guohui Qi Ke Mao Fengwang Ma 《Horticultural Plant Journal》 SCIE CAS CSCD 2024年第3期629-640,共12页
Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drou... Abiotic stress reduces plant yield and quality.WRKY transcription factors play key roles in abiotic stress responses in plants,but the molecular mechanisms by which WRKY transcription factors mediate responses to drought and osmotic stresses in apple(Malus×domestica Borkh.)remain unclear.Here,we functionally characterized the apple GroupⅢWRKY gene MdWRKY115.qRT-PCR analysis showed that MdWRKY115 expression was up-regulated by drought and osmotic stresses.GUS activity analysis revealed that the promoter activity of MdWRKY115 was enhanced under osmotic stress.Subcellular localization and transactivation assays indicated that MdWRKY115 was localized to the nucleus and had a transcriptional activity domain at the N-terminal region.Transgenic analysis revealed that the overexpression of MdWRKY115 in Arabidopsis plants and in apple callus markedly enhanced their tolerance to drought and osmotic stresses.DNA affinity purification sequencing showed that MdWRKY115 binds to the promoter of the stress-related gene MdRD22.This binding was further verified by an electrophoretic mobility shift assay.Collectively,these findings suggest that MdWRKY115 is an important regulator of osmotic and drought stress tolerance in apple. 展开更多
关键词 APPLE MdWRKY115 Osmotic stress Drought stress Function analysis
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3D digital-image correlation insight into generalized relaxation behavior of sandstone under stress and pore pressure coupling
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作者 Cancan Chen Heping Xie +4 位作者 Jiang Xu Seisuke Okubo Shoujian Peng Cunbao Li Minghui Li 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第7期2516-2536,共21页
The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stres... The occurrence of geological hazards and the instability of geotechnical engineering structures are closely related to the time-dependent behavior of rock.However,the idealization boundary condition for constant stress in creep or constant strain in relaxation is not usually attained in natural geological systems.Therefore,generalized relaxation tests that explore the simultaneous changes of stress and strain with time under different stress levels with constant pore-water pressure are conducted in this study.The results show that in area I,area II,and area III,the stress and strain both change synchronously with time and show similar evolutionary laws as the strain-time curve for creep or the stress-time curve for relaxation.When the applied stress level surpasses the sci or scd threshold,the variations in stress and strain and their respective rates of change exhibit a significant increase.The radial deformation and its rate of change exhibit greater sensitivity in response to stress levels.The apparent strain deforms homogeneously at the primary stage,and subsequently,gradually localizes due to the microcrack development at the secondary stage.Ultimately,interconnection of the microcracks causes the formation of a shear-localization zone at the tertiary stage.The strain-time responses inside and outside the localization zone are characterized by local strain accumulation and inelastic unloading during the secondary and tertiary stages,respectively.The width of the shear-localization zone is found to range from 4.43 mm to 7.08 mm and increased with a longer time-to-failure.Scanning electron microscopy(SEM)reveals a dominant coalescence of intergranular cracks on the fracture surface,and the degree of physiochemical deterioration caused by water-rock interaction is more severe under a longer lifetime.The brittle sandstone’s time-dependent deformation is essentially controlled by microcrack development during generalized relaxation,and its expectancy-life is determined by its initial microstructural state and the rheological path. 展开更多
关键词 Generalized relaxation stress level Direction coefficient Major-strain field Microcrack damage stress threshold
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Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior
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作者 Man Han Deyang Zeng +7 位作者 Wei Tan Xingxing Chen Shuyuan Bai Qiong Wu Yushan Chen Zhen Wei Yufei Mei Yan Zeng 《Neural Regeneration Research》 SCIE CAS 2025年第1期159-173,共15页
Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice ... Brain-derived neurotrophic factor is a key factor in stress adaptation and avoidance of a social stress behavioral response.Recent studies have shown that brain-derived neurotrophic factor expression in stressed mice is brain region–specific,particularly involving the corticolimbic system,including the ventral tegmental area,nucleus accumbens,prefrontal cortex,amygdala,and hippocampus.Determining how brain-derived neurotrophic factor participates in stress processing in different brain regions will deepen our understanding of social stress psychopathology.In this review,we discuss the expression and regulation of brain-derived neurotrophic factor in stress-sensitive brain regions closely related to the pathophysiology of depression.We focused on associated molecular pathways and neural circuits,with special attention to the brain-derived neurotrophic factor–tropomyosin receptor kinase B signaling pathway and the ventral tegmental area–nucleus accumbens dopamine circuit.We determined that stress-induced alterations in brain-derived neurotrophic factor levels are likely related to the nature,severity,and duration of stress,especially in the above-mentioned brain regions of the corticolimbic system.Therefore,BDNF might be a biological indicator regulating stress-related processes in various brain regions. 展开更多
关键词 AMYGDALA chronic mild stress chronic social defeat stress corticolimbic system DEPRESSION HIPPOCAMPUS medial prefrontal cortex nucleus accumbens social stress models ventral tegmental area
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Effect of organic mineral supplementation in reducing oxidative stress in Holstein calves during short‑term heat stress and recovery conditions
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作者 A-Rang Son Seon-Ho Kim +3 位作者 Mahfuzul Islam Michelle Miguel Ye Pyae Naing Sang-Suk Lee 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期812-825,共14页
Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)duri... Background This study investigated the effects of inorganic and organic minerals on physiological responses,oxidative stress reduction,and rumen microbiota in Holstein bull calves(123.81±9.76 kg;5 months old)during short-term heat stress(HS)and recovery periods.Eight Holstein calves were randomly assigned to four treatment groups:no mineral supplementation(Con),inorganic minerals(IM),organic minerals(OM),and high-concentration organic minerals(HOM)and two thermal environments(HS and recovery)using 4×2 factorial arrangement in a crossover design of four periods of 35 d.Calves were maintained in a temperature-controlled barn.The experimental period consisted of 14 d of HS,14 d of recovery condititon,and a 7-d washing period.Results Body temperature and respiration rate were higher in HS than in the recovery conditions(P<0.05).Selenium concentration in serum was high in the HOM-supplemented calves in both HS(90.38μg/dL)and recovery periods(102.00μg/dL)(P<0.05).During the HS period,the serum cortisol was 20.26 ng/mL in the HOM group,which was 5.60 ng/mL lower than in the control group(P<0.05).The total antioxidant status was the highest in the OM group(2.71 mmol Trolox equivalent/L),followed by the HOM group during HS,whereas it was highest in the HOM group(2.58 mmol Trolox equivalent/L)during the recovery period(P<0.05).Plasma malondialdehyde and HSP70 levels were decreased by HOM supplementation during the HS and recovery periods,whereas SOD and GPX levels were not significantly affected(P>0.05).The principal coordinate analysis represented that the overall rumen microbiota was not influenced by mineral supplementation;however,temperature-induced microbial structure shifts were indicated(PERMANOVA:P<0.05).At the phylum level,Firmicutes and Actinobacteria decreased,whereas Fibrobacteres,Spirochaetes,and Tenericutes increased(P<0.05),under HS conditions.The genus Treponema increased under HS conditions,while Christensenella was higher in recovery conditions(P<0.05).Conclusion HOM supplementation during HS reduced cortisol concentrations and increased total antioxidant status in Holstein bull calves,suggesting that high organic mineral supplementation may alleviate the adverse effects of HS. 展开更多
关键词 Antioxidant status Heat stress Holstein bull calves Organic mineral supplementation Oxidative stress
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Lactobacillus plantarum AR113 attenuates liver injury in D-galactose-induced aging mice via the inhibition of oxidative stress and endoplasmic reticulum stress
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作者 Yongjun Xia Yujie Gong +8 位作者 Xiangna Lin Yijin Yang Xin Song Guangqiang Wang Zhiqiang Xiong Yangyang Qian Zhuan Liao Hui Zhang Lianzhong Ai 《Food Science and Human Wellness》 SCIE CSCD 2024年第2期885-897,共13页
Probiotics could effectively eliminate excess reactive oxygen species(ROS)generated during aging or lipid metabolism disorders,but their mechanism is unclear.The major purpose of this study was to investigate the mech... Probiotics could effectively eliminate excess reactive oxygen species(ROS)generated during aging or lipid metabolism disorders,but their mechanism is unclear.The major purpose of this study was to investigate the mechanism of Lactiplantibacillus plantarun AR113 alleviating oxidative stress injury in the D-galactose induced aging mice.The result showed that pretreatment with L.plantarun AR113 significantly relieving H_(2)O_(2)induced cytotoxicity in HepG2 cells by maintain cell membrane integrity and increasing antioxidant enzyme activities.In D-galactose induced aging mice,L.plantarun AR113 could significantly attenuate liver damage and inflammatory infiltration by promoting endogenous glutathione(GSH)synthesis and activating the Nrf2/Keap1 signaling pathway in mice,and increasing the expression of regulated phaseⅡdetoxification enzymes and antioxidant enzymes.Further analysis shown that gavage of L.plantarun AR113 could significantly reduce the expression of G protein-coupled receptor 78(GPR78)and C/EBP homologous protein(CHOP)proteins,and promote the restoration of endoplasmic reticulum(ER)homeostasis,thereby activating cell anti-apoptotic pathways.These results were also confirmed in H_(2)O_(2)-treated HepG2 experiments.It indicated that L.plantarun AR113 could inhibit D-galactose-induced liver injury through dual inhibition of ER stress and oxidative stress.L.plantarun AR113 have good application potential in anti-aging and alleviating metabolic disorders. 展开更多
关键词 Lactiplantibacillus plantarun AR113 HEPG2 D-GALACTOSE Oxidative stress ER stress
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Consequences of early life stress on the structure and function of the adult mouse retina
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作者 Juan S.Calanni Ruth E.Rosenstein 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第1期150-151,共2页
Early-life stress(ELS)refers to a period of environmental/social deprivation,physica l,sexual or emotional abuse,neglect,severe and/or chronic trauma in the prenatal/early postnatal stage,which is closely related to m... Early-life stress(ELS)refers to a period of environmental/social deprivation,physica l,sexual or emotional abuse,neglect,severe and/or chronic trauma in the prenatal/early postnatal stage,which is closely related to many adverse psychiatric disorders later in life,such as depressive disorder,substance abuse,dysthymia,panic,anxiety,and suicidal behavior in adulthood(Waters and Gould,2022). 展开更多
关键词 stress LIFE GOULD
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Piezo1 channel exaggerates ferroptosis of nucleus pulposus cells by mediating mechanical stress-induced iron influx
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作者 Ziqian Xiang Pengfei Zhang +15 位作者 Chunwang Jia Rongkun Xu Dingren Cao Zhaoning Xu Tingting Lu Jingwei Liu Xiaoxiong Wang Cheng Qiu Wenyang Fu Weiwei Li Lei Cheng Qiang Yang Shiqing Feng Lianlei Wang Yunpeng Zhao Xinyu Liu 《Bone Research》 SCIE CAS CSCD 2024年第2期334-348,共15页
To date,several molecules have been found to facilitate iron influx,while the types of iron influx channels remain to be elucidated.Here,Piezo1 channel was identified as a key iron transporter in response to mechanica... To date,several molecules have been found to facilitate iron influx,while the types of iron influx channels remain to be elucidated.Here,Piezo1 channel was identified as a key iron transporter in response to mechanical stress.Piezo1-mediated iron overload disturbed iron metabolism and exaggerated ferroptosis in nucleus pulposus cells(NPCs).Importantly,Piezo1-induced iron influx was independent of the transferrin receptor(TFRC),a well-recognized iron gatekeeper.Furthermore,pharmacological inactivation of Piezo1 profoundly reduced iron accumulation,alleviated mitochondrial ROS,and suppressed ferroptotic alterations in stimulation of mechanical stress.Moreover,conditional knockout of Piezo1(Col2a1-CreERT Piezo1^(flox/flox))attenuated the mechanical injury-induced intervertebral disc degeneration(IVDD).Notably,the protective effect of Piezo1 deficiency in IVDD was dampened in Piezo1/Gpx4 conditional double knockout(cDKO)mice(Col2a1-CreERT Piezo1^(flox/flox)/Gpx4^(flox/flox)).These findings suggest that Piezo1 is a potential determinant of iron influx,indicating that the Piezo1-iron-ferroptosis axis might shed light on the treatment of mechanical stress-induced diseases. 展开更多
关键词 stress OVERLOAD CHANNEL
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Effect of Blasting Stress Wave on Dynamic Crack Propagation
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作者 Huizhen Liu Duanying Wan +2 位作者 Meng Wang Zheming Zhu Liyun Yang 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期349-368,共20页
Stress waves affect the stress field at the crack tip and dominate the dynamic crack propagation.Therefore,evaluating the influence of blasting stress waves on the crack propagation behavior and the mechanical charact... Stress waves affect the stress field at the crack tip and dominate the dynamic crack propagation.Therefore,evaluating the influence of blasting stress waves on the crack propagation behavior and the mechanical characteristics of crack propagation is of great significance for engineering blasting.In this study,ANSYS/LS-DYNA was used for blasting numerical simulation,in which the propagation characteristics of blasting stress waves and stress field distribution at the crack tip were closely observed.Moreover,ABAQUS was applied for simulating the crack propagation path and calculating dynamic stress intensity factors(DSIFs).The universal function was calculated by the fractalmethod.The results show that:the compressive wave causes the crack to close and the reflected tensile wave drives the crack to initiate and propagate,and failure mode is mainly tensile failure.The crack propagation velocity varies with time,which increases at first and then decreases,and the crack arrest occurs due to the attenuation of stress waves and dissipation of the blasting energy.In addition,crack arrest toughness is smaller than the crack initiation toughness,applied pressure waveforms(such as the peak pressure,duration,waveforms,wavelengths and loading rates)have a great influence on DSIFs.It is conducive to our deep understanding or the study of blasting stress waves dominated fracture,suggesting a broad reference for the further development of rock blasting in engineering practice. 展开更多
关键词 Crack propagation blasting stress wave dynamic stress intensity factor pressure waveform numerical simulation
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