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Theoretical Analysis of Simulating the Locked-In Stress in Rock Pore by Thermal Expansion of Hard Rubber
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作者 Lu Dong Hansheng Geng +1 位作者 Hongfa Xu Yinhao Yang 《Open Journal of Civil Engineering》 2020年第2期83-92,共10页
Rocks are composed of mineral particles and micropores between mineral which has a great influence on the mechanical properties of rocks. In this paper, based on the theory of locked-in stress developed by academician... Rocks are composed of mineral particles and micropores between mineral which has a great influence on the mechanical properties of rocks. In this paper, based on the theory of locked-in stress developed by academician Chen Zongji, the locked-in stress problem in underground rock is simulated by the thermal expansion of hard rubber particles. The pore inclusion in rock is assumed to be uniformly distributed spherical cavities. Using the thermal stress theory, the stress of rock with a spherical pore inclusion is equivalent to the thermal stress generated by the spherical hard rubber inclusion. The elastic theory formula of the temperature increment and the equivalent pore pressure of the spherical hard rubber inclusion is derived. The numerical simulation of the rock mass model with a spherical hard rubber inclusion is carried out and compared to the theoretical calculation results<span lang="EN-US" style="font-family:;" minion="" pro="" capt",serif;font-size:10pt;mso-fareast-font-family:宋体;mso-bidi-font-family:"times="" new="" roman";mso-ansi-language:en-us;mso-fareast-language:zh-cn;mso-bidi-language:ar-sa;mso-bidi-font-weight:bold;"="">;</span><span lang="EN-US" style="font-family:;" minion="" pro="" capt",serif;font-size:10pt;mso-fareast-font-family:宋体;mso-bidi-font-family:"times="" new="" roman";mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa;mso-bidi-font-weight:bold;"=""> the results show that they are consistent. The method proposed by this paper for simulating stress distribution in rock by thermal stress is reasonable and feasible</span><span lang="EN-US" style="font-family:;" minion="" pro="" capt",serif;font-size:10pt;mso-fareast-font-family:宋体;mso-bidi-font-family:"times="" new="" roman";mso-ansi-language:en-us;mso-fareast-language:zh-cn;mso-bidi-language:ar-sa;mso-bidi-font-weight:bold;"="">;</span><span lang="EN-US" style="font-family:;" minion="" pro="" capt",serif;font-size:10pt;mso-fareast-font-family:宋体;mso-bidi-font-family:"times="" new="" roman";mso-ansi-language:en-us;mso-fareast-language:en-us;mso-bidi-language:ar-sa;mso-bidi-font-weight:bold;"=""> it has a positive meaning for further study of mechanic phenomenon of rock with micropore inclusion.</span> 展开更多
关键词 Rock Pore locked-in stress Similar Simulation Rubber Particles Ther-mal Expansion
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Ferroptosis and endoplasmic reticulum stress in ischemic stroke 被引量:6
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作者 Yina Li Mingyang Li +4 位作者 Shi Feng Qingxue Xu Xu Zhang Xiaoxing Xiong Lijuan Gu 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期611-618,共8页
Ferroptosis is a form of non-apoptotic programmed cell death,and its mechanisms mainly involve the accumulation of lipid peroxides,imbalance in the amino acid antioxidant system,and disordered iron metabolism.The prim... Ferroptosis is a form of non-apoptotic programmed cell death,and its mechanisms mainly involve the accumulation of lipid peroxides,imbalance in the amino acid antioxidant system,and disordered iron metabolism.The primary organelle responsible for coordinating external challenges and internal cell demands is the endoplasmic reticulum,and the progression of inflammatory diseases can trigger endoplasmic reticulum stress.Evidence has suggested that ferroptosis may share pathways or interact with endoplasmic reticulum stress in many diseases and plays a role in cell survival.Ferroptosis and endoplasmic reticulum stress may occur after ischemic stroke.However,there are few reports on the interactions of ferroptosis and endoplasmic reticulum stress with ischemic stroke.This review summarized the recent research on the relationships between ferroptosis and endoplasmic reticulum stress and ischemic stroke,aiming to provide a reference for developing treatments for ischemic stroke. 展开更多
关键词 cell death endoplasmic reticulum stress ferroptosis ischemic stroke lipid peroxidation
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Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress 被引量:1
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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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Piezo1 channel exaggerates ferroptosis of nucleus pulposus cells by mediating mechanical stress-induced iron influx 被引量:2
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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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Impact of effective stress on permeability for carbonate fractured-vuggy rocks 被引量:1
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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 被引量:1
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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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Brain region-specific roles of brain-derived neurotrophic factor in social stress-induced depressive-like behavior 被引量:1
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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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Adverse effects of early-life stress:focus on the rodent neuroendocrine system 被引量:3
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作者 Seung Hyun Lee Eui-Man Jung 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第2期336-341,共6页
Early-life stress is associated with a high prevalence of mental illnesses such as post-traumatic stress disorders,attention-deficit/hyperactivity disorder,schizophrenia,and anxiety or depressive behavior,which consti... Early-life stress is associated with a high prevalence of mental illnesses such as post-traumatic stress disorders,attention-deficit/hyperactivity disorder,schizophrenia,and anxiety or depressive behavior,which constitute major public health problems.In the early stages of brain development after birth,events such as synaptogenesis,neuron maturation,and glial differentiation occur in a highly orchestrated manner,and external stress can cause adverse long-term effects throughout life.Our body utilizes multifaceted mechanisms,including neuroendocrine and neurotransmitter signaling pathways,to appropriately process external stress.Newborn individuals first exposed to early-life stress deploy neurogenesis as a stress-defense mechanism;however,in adulthood,early-life stress induces apoptosis of mature neurons,activation of immune responses,and reduction of neurotrophic factors,leading to anxiety,depression,and cognitive and memory dysfunction.This process involves the hypothalamus-pituitary-adrenal axis and neurotransmitters secreted by the central nervous system,including norepinephrine,dopamine,and serotonin.The rodent early-life stress model is generally used to experimentally assess the effects of stress during neurodevelopment.This paper reviews the use of the early-life stress model and stress response mechanisms of the body and discusses the experimental results regarding how early-life stress mediates stress-related pathways at a high vulnerability of psychiatric disorder in adulthood. 展开更多
关键词 early-life stress hypothalamic-pituitary-adrenergic axis maternal separation mental illness neurodevelopmental disorder neuroendocrine system NEUROTRANSMITTER
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A semi-analytical model for coupled flow in stress-sensitive multi-scale shale reservoirs with fractal characteristics 被引量:2
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作者 Qian Zhang Wen-Dong Wang +4 位作者 Yu-Liang Su Wei Chen Zheng-Dong Lei Lei Li Yong-Mao Hao 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期327-342,共16页
A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes... A large number of nanopores and complex fracture structures in shale reservoirs results in multi-scale flow of oil. With the development of shale oil reservoirs, the permeability of multi-scale media undergoes changes due to stress sensitivity, which plays a crucial role in controlling pressure propagation and oil flow. This paper proposes a multi-scale coupled flow mathematical model of matrix nanopores, induced fractures, and hydraulic fractures. In this model, the micro-scale effects of shale oil flow in fractal nanopores, fractal induced fracture network, and stress sensitivity of multi-scale media are considered. We solved the model iteratively using Pedrosa transform, semi-analytic Segmented Bessel function, Laplace transform. The results of this model exhibit good agreement with the numerical solution and field production data, confirming the high accuracy of the model. As well, the influence of stress sensitivity on permeability, pressure and production is analyzed. It is shown that the permeability and production decrease significantly when induced fractures are weakly supported. Closed induced fractures can inhibit interporosity flow in the stimulated reservoir volume (SRV). It has been shown in sensitivity analysis that hydraulic fractures are beneficial to early production, and induced fractures in SRV are beneficial to middle production. The model can characterize multi-scale flow characteristics of shale oil, providing theoretical guidance for rapid productivity evaluation. 展开更多
关键词 Multi-scale coupled flow stress sensitivity Shale oil Micro-scale effect Fractal theory
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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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Pre‑hatch thermal manipulation of embryos and post‑hatch baicalein supplementation mitigated heat stress in broiler chickens 被引量:1
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作者 Sadid Al Amaz Ajay Chaudhary +2 位作者 Prem Lal Mahato Rajesh Jha Birendra Mishra 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第3期1071-1085,共15页
Background High environmental temperatures induce heat stress in broiler chickens,affecting their health and pro-duction performance.Several dietary,managerial,and genetics strategies have been tested with some succes... Background High environmental temperatures induce heat stress in broiler chickens,affecting their health and pro-duction performance.Several dietary,managerial,and genetics strategies have been tested with some success in mitigating heat stress(HS)in broilers.Developing novel HS mitigation strategies for sustaining broiler production is critically needed.This study investigated the effects of pre-hatch thermal manipulation(TM)and post-hatch baica-lein supplementation on growth performance and health parameters in heat-stressed broilers.Results Six hundred fertile Cobb 500 eggs were incubated for 21 d.After candling on embryonic day(ED)10,238 eggs were thermally manipulated at 38.5℃ with 55%relative humidity(RH)from ED 12 to 18,then transferred to the hatcher(ED 19 to 21,standard temperature)and 236 eggs were incubated at a controlled temperature(37.5℃)till hatch.After hatch,180-day-old chicks from both groups were raised in 36 pens(n=10 birds/pen,6 replicates per treatment).The treatments were:1)Control,2)TM,3)control heat stress(CHS),4)thermal manipulation heat stress(TMHS),5)control heat stress supplement(CHSS),and 6)thermal manipulation heat stress supplement(TMHSS).All birds were raised under the standard environment for 21 d,followed by chronic heat stress from d 22 to 35(32–33℃ for 8 h)in the CHS,TMHS,CHSS,and TMHSS groups.A thermoneutral(22–24℃)environment was maintained in the Control and TM groups.RH was constant(50%±5%)throughout the trial.All the data were analyzed using one-way ANOVA in R and GraphPad software at P<0.05 and are presented as mean±SEM.Heat stress significantly decreased(P<0.05)the final body weight and ADG in CHS and TMHS groups compared to the other groups.Embryonic TM significantly increased(P<0.05)the expression of heat shock protein-related genes(HSP70,HSP90,and HSPH1)and antioxidant-related genes(GPX1 and TXN).TMHS birds showed a significant increment(P<0.05)in total cecal volatile fatty acid(VFA)concentration compared to the CHS birds.The cecal microbial analysis showed significant enrichment(P<0.05)in alpha and beta diversity and Coprococcus in the TMHSS group.Conclusions Pre-hatch TM and post-hatch baicalein supplementation in heat-stressed birds mitigate the detrimental effects of heat stress on chickens’growth performance,upregulate favorable gene expression,increase VFA produc-tion,and promote gut health by increasing beneficial microbial communities. 展开更多
关键词 BAICALEIN Growth performance Gut microbiota Heat stress Thermal manipulation
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Effect of icosahedral phase formation on the stress corrosion cracking(SCC)behaviors of the as-cast Mg-8%Li(in wt.%)based alloys 被引量:1
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作者 Shuo Wang Daokui Xu +2 位作者 Dongliang Wang Zhiqiang Zhang Baojie Wang 《Journal of Magnesium and Alloys》 SCIE EI CAS CSCD 2024年第1期225-236,共12页
Through exploring the stress corrosion cracking(SCC)behaviors of the as-cast Mg-8%Li and Mg-8%Li-6%Zn-1.2%Y alloys in a 0.1 M NaCl solution,it revealed that the SCC susceptibility index(I_(SCC))of the Mg-8%Li alloy wa... Through exploring the stress corrosion cracking(SCC)behaviors of the as-cast Mg-8%Li and Mg-8%Li-6%Zn-1.2%Y alloys in a 0.1 M NaCl solution,it revealed that the SCC susceptibility index(I_(SCC))of the Mg-8%Li alloy was 47%,whilst the I_(SCC)of the Mg-8%Li-6%Zn-1.2%Y alloy was 68%.Surface,cross-sectional and fractography observations indicated that for the Mg-8%Li alloy,theα-Mg/β-Li interfaces acted as the preferential crack initiation sites and propagation paths during the SCC process.With regard to the Mg-8%Li-6%Zn-1.2%Y alloy,the crack initiation sites included the I-phase and the interfaces of I-phase/β-Li andα-Mg/β-Li,and the preferential propagation paths were the I-phase/β-Li andα-Mg/β-Li interfaces.Moreover,the SCC of the two alloys was concerned with hydrogen embrittlement(HE)mechanism. 展开更多
关键词 Magnesium-lithium alloy stress corrosion cracking I-phase Fracture analysis
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Evolution of microstructure and properties of a novel Ni-based superalloy during stress relief annealing 被引量:1
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作者 Lei Jia Heng Cui +3 位作者 Shufeng Yang Shaomin Lü Xingfei Xie Jinglong Qu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2024年第8期1876-1889,共14页
We discussed the decrease in residual stress,precipitation evolution,and mechanical properties of GH4151 alloy in different annealing temperatures,which were studied by the scanning electron microscope(SEM),high-resol... We discussed the decrease in residual stress,precipitation evolution,and mechanical properties of GH4151 alloy in different annealing temperatures,which were studied by the scanning electron microscope(SEM),high-resolution transmission electron microscopy(HRTEM),and electron backscatter diffraction(EBSD).The findings reveal that annealing processing has a significant impact on diminishing residual stresses.As the annealing temperature rose from 950 to 1150℃,the majority of the residual stresses were relieved from 60.1 MPa down to 10.9 MPa.Moreover,the stress relaxation mechanism transitioned from being mainly controlled by dislocation slip to a combination of dislocation slip and grain boundary migration.Meanwhile,the annealing treatment promotes the decomposition of the Laves,accompanied by the precipitation ofμ-(Mo_(6)Co_(7))starting at 950℃ and reaching a maximum value at 1050℃.The tensile strength and plasticity of the annealing alloy at 1150℃ reached the maximum(1394 MPa,56.1%)which was 131%,200%fold than those of the as-cast alloy(1060 MPa,26.6%),but the oxidation process in the alloy was accelerated at 1150℃.The enhancement in durability and flexibility is primarily due to the dissolution of the brittle phase,along with the shape and dispersal of theγ′phase. 展开更多
关键词 GH4151 alloy annealing treatment residual stress precipitation evolution STRENGTH mechanical properties
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U-Net Models for Representing Wind Stress Anomalies over the Tropical Pacific and Their Integrations with an Intermediate Coupled Model for ENSO Studies 被引量:1
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作者 Shuangying Du Rong-Hua Zhang 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第7期1403-1416,共14页
El Niño-Southern Oscillation(ENSO)is the strongest interannual climate mode influencing the coupled ocean-atmosphere system in the tropical Pacific,and numerous dynamical and statistical models have been develope... El Niño-Southern Oscillation(ENSO)is the strongest interannual climate mode influencing the coupled ocean-atmosphere system in the tropical Pacific,and numerous dynamical and statistical models have been developed to simulate and predict it.In some simplified coupled ocean-atmosphere models,the relationship between sea surface temperature(SST)anomalies and wind stress(τ)anomalies can be constructed by statistical methods,such as singular value decomposition(SVD).In recent years,the applications of artificial intelligence(AI)to climate modeling have shown promising prospects,and the integrations of AI-based models with dynamical models are active areas of research.This study constructs U-Net models for representing the relationship between SSTAs andτanomalies in the tropical Pacific;the UNet-derivedτmodel,denoted asτUNet,is then used to replace the original SVD-basedτmodel of an intermediate coupled model(ICM),forming a newly AI-integrated ICM,referred to as ICM-UNet.The simulation results obtained from ICM-UNet demonstrate their ability to represent the spatiotemporal variability of oceanic and atmospheric anomaly fields in the equatorial Pacific.In the ocean-only case study,theτUNet-derived wind stress anomaly fields are used to force the ocean component of the ICM,the results of which also indicate reasonable simulations of typical ENSO events.These results demonstrate the feasibility of integrating an AI-derived model with a physics-based dynamical model for ENSO modeling studies.Furthermore,the successful integration of the dynamical ocean models with the AI-based atmospheric wind model provides a novel approach to ocean-atmosphere interaction modeling studies. 展开更多
关键词 U-Net models wind stress anomalies ICM integration of AI and physical components
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Knockdown of the atypical protein kinase genes GhABC1K2-A05 and GhABC1K12-A07 make cotton more sensitive to salt and PEG stress 被引量:1
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作者 Caixiang Wang Meili Li +3 位作者 Dingguo Zhang Xueli Zhang Juanjuan Liu Junji Su 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第10期3370-3386,共17页
Activity of bc1 complex kinase(ABC1K)is an atypical protein kinase(aPK)that plays a crucial role in plant mitochondrial and plastid stress responses,but little is known about the responses of ABC1Ks to stress in cotto... Activity of bc1 complex kinase(ABC1K)is an atypical protein kinase(aPK)that plays a crucial role in plant mitochondrial and plastid stress responses,but little is known about the responses of ABC1Ks to stress in cotton(Gossypium spp.).Here,we identified 40 ABC1Ks in upland cotton(Gossypium hirsutum L.)and found that the Gh ABC1Ks were unevenly distributed across 17 chromosomes.The GhABC1K family members included 35 paralogous gene pairs and were expanded by segmental duplication.The GhABC1K promoter sequences contained diverse cis-acting regulatory elements relevant to hormone or stress responses.The qRT-PCR results revealed that most Gh ABC1Ks were upregulated by exposure to different stresses.Gh ABC1K2-A05 and Gh ABC1K12-A07 expression levels were upregulated by at least three stress treatments.These genes were further functionally characterized by virus-induced gene silencing(VIGS).Compared with the controls,the Gh ABC1K2-A05-and Gh ABC1K12-A07-silenced cotton lines exhibited higher malondialdehyde(MDA)contents,lower catalase(CAT),peroxidase(POD)and superoxide dismutase(SOD)activities and reduced chlorophyll and soluble sugar contents under NaCl and PEG stress.In addition,the expression levels of six stress marker genes(Gh DREB2A,Gh SOS1,Gh CIPK6,Gh SOS2,Gh WRKY33,and Gh RD29A)were significantly downregulated after stress in the Gh ABC1K2-A05-and Gh ABC1K12-A07-silenced lines.The results indicate that knockdown of Gh ABC1K2-A05 and Gh ABC1K12-A07 make cotton more sensitive to salt and PEG stress.These findings can provide valuable information for intensive studies of Gh ABC1Ks in the responses and resistance of cotton to abiotic stresses. 展开更多
关键词 COTTON ABC1K abiotic stress responses expression patterns virus-induced gene silencing(VIGS)
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Inflammatory markers,oxidative stress,and mitochondrial dynamics:Repercussions on coronary artery disease in diabetes 被引量:1
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作者 JoséCarlos Tatmatsu-Rocha Luan Santos Mendes-Costa 《World Journal of Diabetes》 SCIE 2024年第9期1853-1857,共5页
Inflammatory markers and mediators that affect the development of cardiovascular diseases have been the focus of recent scientific work.Thus,the purpose of this editorial is to promote a critical debate about the arti... Inflammatory markers and mediators that affect the development of cardiovascular diseases have been the focus of recent scientific work.Thus,the purpose of this editorial is to promote a critical debate about the article titled“Nε-carboxymethyl-lysine and inflammatory cytokines,markers,and mediators of coronary artery disease progression in diabetes”,published in the World Journal of Diabetes in 2024.This work directs us to reflect on the role of advanced glycation end products,which are pro-inflammatory products arising from the metabolism of fatty acids and sugars whose main marker in tissues is Nε-carboxymethyllysine(NML).Recent studies have linked high levels of pro-inflammatory agents with the development of coronary artery disease(CAD),especially tumor necrosis factor alpha,interleukins,and C-reactive protein.These inflammatory agents increase the production of reactive oxygen species(ROS),of which people with diabetes are known to have an increased production.The increase in ROS promotes lipid peroxidation,which causes damage to myocytes,promoting myocardial damage.Furthermore,oxidative stress induces the binding of NML to its receptor RAGE,which in turn activates the nuclear factor-kB,and consequently,inflammatory cytokines.These inflammatory cytokines induce endothelial dysfunction,with increased expression of adhesion molecules,changes in endothelial permeability and changes in the expression of nitric oxide.In this sense,the therapeutic use of monoclonal antibodies(inflammatory reducers such as statins and sodium-glucose transport inhibitors)has demonstrated positive results in the regression of atherogenic plaques and consequently CAD.On the other hand,many studies have demonstrated a relationship between mitochondrial dynamics,diabetes,and cardiovascular diseases.This link occurs since ROS have their origin in the imbalance in glucose metabolism that occurs in the mitochondrial matrix,and this imbalance can have its origin in inadequate diet as well as some pathologies.Photobiomodulation(PBM)has recently been considered a possible therapeutic agent for cardiovascular diseases due to its effects on mitochondrial dynamics and oxidative stress.In this sense,therapies such as PBM that act on pro-inflammatory mediators and mitochondrial modulation could benefit those with cardiovascular diseases. 展开更多
关键词 Mitochondrial dynamics DIABETES Oxidative stress Coronary artery disease Nε-carboxymethyl-lysine
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Activation of the wnt/β-catenin/CYP1B1 pathway alleviates oxidative stress and protects the blood-brain barrier under cerebral ischemia/reperfusion conditions 被引量:6
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作者 Xingyong Chen Nannan Yao +4 位作者 Yanguang Mao Dongyun Xiao Yiyi Huang Xu Zhang Yinzhou Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第7期1541-1547,共7页
Accumulating evidence suggests that oxidative stress and the Wnt/β-catenin pathway participate in stroke-induced disruption of the blood-brain barrier.However,the potential links between them following ischemic strok... Accumulating evidence suggests that oxidative stress and the Wnt/β-catenin pathway participate in stroke-induced disruption of the blood-brain barrier.However,the potential links between them following ischemic stroke remain largely unknown.The present study found that cerebral ischemia leads to oxidative stress and repression of the Wnt/β-catenin pathway.Meanwhile,Wnt/β-catenin pathway activation by the pharmacological inhibito r,TWS119,relieved oxidative stress,increased the levels of cytochrome P4501B1(CYP1B1)and tight junction-associated proteins(zonula occludens-1[ZO-1],occludin and claudin-5),as well as brain microvascular density in cerebral ischemia rats.Moreove r,rat brain microvascular endothelial cells that underwent oxygen glucose deprivation/reoxygenation displayed intense oxidative stress,suppression of the Wnt/β-catenin pathway,aggravated cell apoptosis,downregulated CYP1B1and tight junction protein levels,and inhibited cell prolife ration and migration.Overexpression ofβ-catenin or knockdown ofβ-catenin and CYP1B1 genes in rat brain mic rovascular endothelial cells at least partly ameliorated or exacerbated these effects,respectively.In addition,small interfering RNA-mediatedβ-catenin silencing decreased CYP1B1 expression,whereas CYP1B1 knoc kdown did not change the levels of glycogen synthase kinase 3β,Wnt-3a,andβ-catenin proteins in rat brain microvascular endothelial cells after oxygen glucose deprivatio n/reoxygenation.Thus,the data suggest that CYP1B1 can be regulated by Wnt/β-catenin signaling,and activation of the Wnt/β-catenin/CYP1B1 pathway contributes to alleviation of oxidative stress,increased tight junction levels,and protection of the blood-brain barrier against ischemia/hypoxia-induced injury. 展开更多
关键词 blood-brain barrier CYP1B1 oxidative stress oxygen glucose deprivation/reoxygenation tight junction vascular endothelial cells Wnt/β-catenin pathway β-catenin
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Treatment with β-sitosterol ameliorates the effects of cerebral ischemia/reperfusion injury by suppressing cholesterol overload, endoplasmic reticulum stress, and apoptosis 被引量:4
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作者 Xiuling Tang Tao Yan +8 位作者 Saiying Wang Qingqing Liu Qi Yang Yongqiang Zhang Yujiao Li Yumei Wu Shuibing Liu Yulong Ma Le Yang 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期642-649,共8页
β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unkno... β-Sitosterol is a type of phytosterol that occurs naturally in plants.Previous studies have shown that it has anti-oxidant,anti-hyperlipidemic,anti-inflammatory,immunomodulatory,and anti-tumor effects,but it is unknown whetherβ-sitosterol treatment reduces the effects of ischemic stroke.Here we found that,in a mouse model of ischemic stroke induced by middle cerebral artery occlusion,β-sitosterol reduced the volume of cerebral infarction and brain edema,reduced neuronal apoptosis in brain tissue,and alleviated neurological dysfunction;moreover,β-sitosterol increased the activity of oxygen-and glucose-deprived cerebral cortex neurons and reduced apoptosis.Further investigation showed that the neuroprotective effects ofβ-sitosterol may be related to inhibition of endoplasmic reticulum stress caused by intracellular cholesterol accumulation after ischemic stroke.In addition,β-sitosterol showed high affinity for NPC1L1,a key transporter of cholesterol,and antagonized its activity.In conclusion,β-sitosterol may help treat ischemic stroke by inhibiting neuronal intracellular cholesterol overload/endoplasmic reticulum stress/apoptosis signaling pathways. 展开更多
关键词 APOPTOSIS blood-brain barrier Β-SITOSTEROL cerebral ischemia/reperfusion injury cholesterol overload cholesterol transport endoplasmic reticulum stress ischemic stroke molecular docking NPC1L1
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Biochanin A attenuates spinal cord injury in rats during early stages by inhibiting oxidative stress and inflammasome activation 被引量:2
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作者 Xigong Li Jing Fu +3 位作者 Ming Guan Haifei Shi Wenming Pan Xianfeng Lou 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第9期2050-2056,共7页
Previous studies have shown that Biochanin A,a flavonoid compound with estrogenic effects,can serve as a neuroprotective agent in the context of cerebral ischemia/reperfusion injury;howeve r,its effect on spinal cord ... Previous studies have shown that Biochanin A,a flavonoid compound with estrogenic effects,can serve as a neuroprotective agent in the context of cerebral ischemia/reperfusion injury;howeve r,its effect on spinal cord injury is still unclea r. In this study,a rat model of spinal cord injury was established using the heavy o bject impact method,and the rats were then treated with Biochanin A(40 mg/kg) via intrape ritoneal injection for 14 consecutive days.The res ults showed that Biochanin A effectively alleviated spinal cord neuronal injury and spinal co rd tissue injury,reduced inflammation and oxidative stress in spinal cord neuro ns,and reduced apoptosis and pyroptosis.In addition,Biochanin A inhibited the expression of inflammasome-related proteins(ASC,NLRP3,and GSDMD)and the Toll-like receptor 4/nuclear factor-κB pathway,activated the Nrf2/heme oxygenase 1 signaling pathway,and increased the expression of the autophagy markers LC3 Ⅱ,Beclin-1,and P62.Moreove r,the therapeutic effects of Biochanin A on early post-s pinal cord injury were similar to those of methylprednisolone.These findings suggest that Biochanin A protected neurons in the injured spinal cord through the Toll-like receptor 4/nuclear factor κB and Nrf2/heme oxygenase 1 signaling pathways.These findings suggest that Biochanin A can alleviate post-spinal cord injury at an early stage. 展开更多
关键词 apoptosis AUTOPHAGY Biochanin A heme oxygenase 1 INFLAMMATION Nrf2 protein nuclear factor kappa-B oxidative stress spinal cord injury Toll-like receptor 4
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Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress 被引量:1
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作者 ZHANG Long ZHAO Tian-feng 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期255-270,共16页
The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating platform.The harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone t... The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating platform.The harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue failure.The structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue evaluation.Here,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural stress.Besides,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into account.The research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR. 展开更多
关键词 SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage
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