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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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Correlation between the rock mass properties and maximum horizontal stress:A case study of overcoring stress measurements
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作者 Peng Li Meifeng Cai +2 位作者 Shengjun Miao Yuan Li Yu Wang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS 2025年第1期39-48,共10页
Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stre... Understanding the mechanical properties of the lithologies is crucial to accurately determine the horizontal stress magnitude.To investigate the correlation between the rock mass properties and maximum horizontal stress,the three-dimensional(3D)stress tensors at 89 measuring points determined using an improved overcoring technique in nine mines in China were adopted,a newly defined characteristic parameter C_(ERP)was proposed as an indicator for evaluating the structural properties of rock masses,and a fuzzy relation matrix was established using the information distribution method.The results indicate that both the vertical stress and horizontal stress exhibit a good linear growth relationship with depth.There is no remarkable correlation between the elastic modulus,Poisson's ratio and depth,and the distribution of data points is scattered and messy.Moreover,there is no obvious relationship between the rock quality designation(RQD)and depth.The maximum horizontal stress σ_(H) is a function of rock properties,showing a certain linear relationship with the C_(ERP)at the same depth.In addition,the overall change trend of σ_(H) determined by the established fuzzy identification method is to increase with the increase of C_(ERP).The fuzzy identification method also demonstrates a relatively detailed local relationship betweenσ_H and C_(ERP),and the predicted curve rises in a fluctuating way,which is in accord well with the measured stress data. 展开更多
关键词 overcoring stress measurements elastic modulus Poisson's ratio rock quality designation maximum horizontal stress fuzzy identification
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Dip2a regulates stress susceptibility in the basolateral amygdala
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作者 Jing Li Zixuan He +4 位作者 Weitai Chai Meng Tian Huali Yu Xiaoxiao He Xiaojuan Zhu 《Neural Regeneration Research》 SCIE CAS 2025年第6期1735-1748,共14页
Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types... Dysregulation of neurotransmitter metabolism in the central nervous system contributes to mood disorders such as depression, anxiety, and post–traumatic stress disorder. Monoamines and amino acids are important types of neurotransmitters. Our previous results have shown that disco-interacting protein 2 homolog A(Dip2a) knockout mice exhibit brain development disorders and abnormal amino acid metabolism in serum. This suggests that DIP2A is involved in the metabolism of amino acid–associated neurotransmitters. Therefore, we performed targeted neurotransmitter metabolomics analysis and found that Dip2a deficiency caused abnormal metabolism of tryptophan and thyroxine in the basolateral amygdala and medial prefrontal cortex. In addition, acute restraint stress induced a decrease in 5-hydroxytryptamine in the basolateral amygdala. Additionally, Dip2a was abundantly expressed in excitatory neurons of the basolateral amygdala, and deletion of Dip2a in these neurons resulted in hopelessness-like behavior in the tail suspension test. Altogether, these findings demonstrate that DIP2A in the basolateral amygdala may be involved in the regulation of stress susceptibility. This provides critical evidence implicating a role of DIP2A in affective disorders. 展开更多
关键词 5-HYDROXYTRYPTAMINE acute restraint stress basolateral amygdala CaMKII neurons DIP2A metabolomics NEUROTRANSMITTERS principal component analysis stress susceptibility TRYPTOPHAN
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Acquired sensorineural hearing loss,oxidative stress,and microRNAs
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作者 Desmond A.Nunez Ru C.Guo 《Neural Regeneration Research》 SCIE CAS 2025年第9期2513-2519,共7页
Hearing loss is the third leading cause of human disability.Age-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health burden.Noise-induced,ototox... Hearing loss is the third leading cause of human disability.Age-related hearing loss,one type of acquired sensorineural hearing loss,is largely responsible for this escalating global health burden.Noise-induced,ototoxic,and idiopathic sudden sensorineural are other less common types of acquired hearing loss.The etiology of these conditions is complex and multi-fa ctorial involving an interplay of genetic and environmental factors.Oxidative stress has recently been proposed as a likely linking cause in most types of acquired sensorineural hearing loss.Short non-coding RNA sequences known as microRNAs(miRNAs)have increasingly been shown to play a role in cellular hypoxia and oxidative stress responses including promoting an apoptotic response.Sensory hair cell death is a central histopathological finding in sensorineural hearing loss.As these cells do not regenerate in humans,it underlies the irreversibility of human age-related hearing loss.Ovid EMBASE,Ovid MEDLINE,Web of Science Core Collection,and ClinicalTrials.gov databases over the period August 1,2018 to July 31,2023 were searched with"hearing loss,""hypoxamiRs,""hypoxia,""microRNAs,""ischemia,"and"oxidative stress"text words for English language primary study publications or registered clinical trials.Registe red clinical trials known to the senior author we re also assessed.A total of 222studies were thus identified.After excluding duplicates,editorials,retra ctions,secondary research studies,and non-English language articles,39 primary studies and clinical trials underwent full-text screening.This resulted in 11 animal,in vitro,and/or human subject journal articles and 8 registered clinical trial database entries which form the basis of this narrative review.MiRNAs miR-34a and miR-29b levels increase with age in mice.These miRNAs were demonstrated in human neuroblastoma and murine cochlear cell lines to target Sirtuin 1/peroxisome proliferato r-activated receptor gamma coactivator-1-alpha(SIRT1/P GC-1α),SIRT1p53,and SIRT1/hypoxia-inducible factor 1-alpha signaling pathways resulting in increased apoptosis.Furthermore,hypoxia and oxidative stress had a similar adve rse apoptotic effect,which was inhibited by resve ratrol and a myocardial inhibitorassociated transcript,a miR-29b competing endogenous mRNA.Gentamicin reduced miR-182-5p levels and increased cochlear oxidative stress and cell death in mice-an effect that was corrected by inner ear stem cell-derived exosomes.There is ongoing work seeking to determine if these findings can be effectively translated to humans. 展开更多
关键词 hearing loss HYPOXIA MICRORNAS oxidative stress SENSORINEURAL
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Posttraumatic stress symptoms among Chinese university students during the COVID-19 pandemic:Prevalence,correlates,and mental health help-seeking
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作者 Rui-Yao Wu Lin-Feng Ge Bao-Liang Zhong 《World Journal of Psychiatry》 SCIE 2025年第1期145-152,共8页
BACKGROUND Revisiting the epidemiology of posttraumatic stress symptoms(PTSSs)among university students during the coronavirus disease 2019(COVID-19)pandemic as well as understanding the mental health help-seeking beh... BACKGROUND Revisiting the epidemiology of posttraumatic stress symptoms(PTSSs)among university students during the coronavirus disease 2019(COVID-19)pandemic as well as understanding the mental health help-seeking behavior of individuals with PTSSs has critical implications for public mental health strategies in future medical pandemics.AIM To investigate the prevalence and correlates of PTSSs among university students during the first wave of the COVID-19 pandemic in China and to examine mental health help-seeking behaviors among these students.METHODS A total of 2507 Chinese university students were recruited via snowball sampling.The students completed the Seven-item Screening Scale for Post-traumatic Stress Disorder during the first wave of the COVID-19 pandemic in China.Sociodemo-graphic characteristics,pandemic-related characteristics,and mental health help-seeking behaviors of students with PTSSs were also collected.RESULTS The prevalence of PTSSs among the participants was 28.0%.Seven significant correlates of PTSSs were identified(odds ratio=1.23-3.65,P≤0.024):Female sex,being 19 years old or older,living with others or alone,a low level of family economic status,fair or poor interpersonal relationships,severe or very severe local pandemic,and having family members diagnosed with COVID-19.However,only 3.28%of the students with PTSSs reported seeking help from mental health specialists.Among the 23 students who sought help from mental health specialists,13 opted for online or telephone-based psychological consultation.CONCLUSION Our data suggest that there was a high risk of PTSSs among university students and a high level of unmet mental health needs during the COVID-19 pandemic.The delivery of mental health services online or via telephone is a promising approach to address these unmet needs. 展开更多
关键词 Posttraumatic stress symptoms University students COVID-19 Mental health help-seeking China
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Relationship between parenting stress and behavioral and emotional problems in preschool children: A mediation effect analysis
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作者 Zhi-Wei Fu Yue-Jing Li +3 位作者 Ran Yu Rui-Qing Guo Li-Xia Gao Sheng-Xia Zhao 《World Journal of Psychiatry》 SCIE 2025年第1期128-136,共9页
BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current statu... BACKGROUND Emotional reactions,such as anxiety,irritability,and aggressive behavior,have attracted clinical attention as behavioral and emotional problems in preschool-age children.AIM To investigate the current status of family rearing,parental stress,and behavioral and emotional problems of preschool children and to analyze the mediating effect of the current status of family rearing on parental stress and behavioral/emo-tional problems.METHODS We use convenience sampling to select 258 preschool children in the physical examination center of our hospital from October 2021 to September 2023.The children and their parents were evaluated using a questionnaire survey.Pearson's correlation was used to analyze the correlation between child behavioral and emotional problems and parental stress and family rearing,and the structural equation model was constructed to test the mediating effect.RESULTS The score for behavioral/emotional problems of 258 preschool children was(27.54±3.63),the score for parental stress was(87.64±11.34),and the score for parental family rearing was(31.54±5.24).There was a positive correlation between the behavioral and emotional problems of the children and the“hostile/mandatory”parenting style;meanwhile,showed a negative correlation with the“support/participation”parenting style(all P<0.05).The intermediary effect value between the family upbringing of parents in parental stress and children's behavior problems was 29.89%.CONCLUSION Parental family upbringing has a mediating effect between parental stress and behavioral and emotional problems of children.Despite paying attention to the behavioral and emotional problems of preschool-age children,clinical medical staff should provide correct and reasonable parenting advice to their parents to promote the mental health of preschool-age children. 展开更多
关键词 Preschool children Parenting stress Children's behavioral and emotional problems Family rearing Mediating effect
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Endoplasmic reticulum stress and autophagy in cerebral ischemia/reperfusion injury:PERK as a potential target for intervention
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作者 Ju Zheng Yixin Li +8 位作者 Ting Zhang Yanlin Fu Peiyan Long Xiao Gao Zhengwei Wang Zhizhong Guan Xiaolan Qi Wei Hong Yan Xiao 《Neural Regeneration Research》 SCIE CAS 2025年第5期1455-1466,共12页
Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion injury.Autophagy occurs within hours after cereb... Several studies have shown that activation of unfolded protein response and endoplasmic reticulum(ER)stress plays a crucial role in severe cerebral ischemia/reperfusion injury.Autophagy occurs within hours after cerebral ischemia,but the relationship between ER stress and autophagy remains unclear.In this study,we established experimental models using oxygen-glucose deprivation/reoxygenation in PC12 cells and primary neurons to simulate cerebral ischemia/reperfusion injury.We found that prolongation of oxygen-glucose deprivation activated the ER stress pathway protein kinase-like endoplasmic reticulum kinase(PERK)/eukaryotic translation initiation factor 2 subunit alpha(e IF2α)-activating transcription factor 4(ATF4)-C/EBP homologous protein(CHOP),increased neuronal apoptosis,and induced autophagy.Furthermore,inhibition of ER stress using inhibitors or by si RNA knockdown of the PERK gene significantly attenuated excessive autophagy and neuronal apoptosis,indicating an interaction between autophagy and ER stress and suggesting PERK as an essential target for regulating autophagy.Blocking autophagy with chloroquine exacerbated ER stress-induced apoptosis,indicating that normal levels of autophagy play a protective role in neuronal injury following cerebral ischemia/reperfusion injury.Findings from this study indicate that cerebral ischemia/reperfusion injury can trigger neuronal ER stress and promote autophagy,and suggest that PERK is a possible target for inhibiting excessive autophagy in cerebral ischemia/reperfusion injury. 展开更多
关键词 APOPTOSIS ATF4 AUTOPHAGY C/EBP homologous protein cerebral ischemia/reperfusion injury EIF2Α endoplasmic reticulum stress PERK
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MicroRNAs as potential biomarkers for diagnosis of post-traumatic stress disorder
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作者 Bridget Martinez Philip V.Peplow 《Neural Regeneration Research》 SCIE CAS 2025年第7期1957-1970,共14页
Post-traumatic stress disorder is a mental disorder caused by exposure to severe traumatic life events.Currently,there are no validated biomarkers or laboratory tests that can distinguish between trauma survivors with... Post-traumatic stress disorder is a mental disorder caused by exposure to severe traumatic life events.Currently,there are no validated biomarkers or laboratory tests that can distinguish between trauma survivors with and without post-traumatic stress disorder.In addition,the heterogeneity of clinical presentations of post-traumatic stress disorder and the overlap of symptoms with other conditions can lead to misdiagnosis and inappropriate treatment.Evidence suggests that this condition is a multisystem disorder that affects many biological systems,raising the possibility that peripheral markers of disease may be used to diagnose post-traumatic stress disorder.We performed a PubMed search for microRNAs(miRNAs)in post-traumatic stress disorder(PTSD)that could serve as diagnostic biomarkers and found 18 original research articles on studies performed with human patients and published January 2012 to December 2023.These included four studies with whole blood,seven with peripheral blood mononuclear cells,four with plasma extracellular vesicles/exosomes,and one with serum exosomes.One of these studies had also used whole plasma.Two studies were excluded as they did not involve microRNA biomarkers.Most of the studies had collected samples from adult male Veterans who had returned from deployment and been exposed to combat,and only two were from recently traumatized adult subjects.In measuring miRNA expression levels,many of the studies had used microarray miRNA analysis,miRNA Seq analysis,or NanoString panels.Only six studies had used real time polymerase chain reaction assay to determine/validate miRNA expression in PTSD subjects compared to controls.The miRNAs that were found/validated in these studies may be considered as potential candidate biomarkers for PTSD and include miR-3130-5p in whole blood;miR-193a-5p,-7113-5p,-125a,-181c,and-671-5p in peripheral blood mononuclear cells;miR-10b-5p,-203a-3p,-4488,-502-3p,-874-3p,-5100,and-7641 in plasma extracellular vesicles/exosomes;and miR-18a-3p and-7-1-5p in blood plasma.Several important limitations identified in the studies need to be taken into account in future studies.Further studies are warranted with war veterans and recently traumatized children,adolescents,and adults having PTSD and use of animal models subjected to various stressors and the effects of suppressing or overexpressing specific microRNAs. 展开更多
关键词 BIOMARKER DIAGNOSIS microRNA peripheral blood mononuclear cells plasma extracellular vesicles/exosomes post-traumatic stress disorder serum exosomes whole blood whole plasma
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Diabetes mellitus and glymphatic dysfunction:Roles for oxidative stress,mitochondria,circadian rhythm,artificial intelligence,and imaging
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作者 Kenneth Maiese 《World Journal of Diabetes》 SCIE 2025年第1期39-48,共10页
Diabetes mellitus(DM)is a debilitating disorder that impacts all systems of the body and has been increasing in prevalence throughout the globe.DM represents a significant clinical challenge to care for individuals an... Diabetes mellitus(DM)is a debilitating disorder that impacts all systems of the body and has been increasing in prevalence throughout the globe.DM represents a significant clinical challenge to care for individuals and prevent the onset of chronic disability and ultimately death.Underlying cellular mechanisms for the onset and development of DM are multi-factorial in origin and involve pathways associated with the production of reactive oxygen species and the generation of oxidative stress as well as the dysfunction of mitochondrial cellular organelles,programmed cell death,and circadian rhythm impairments.These pathways can ultimately involve failure in the glymphatic pathway of the brain that is linked to circadian rhythms disorders during the loss of metabolic homeostasis.New studies incorporate a number of promising techniques to examine patients with metabolic disorders that can include machine learning and artificial intelligence pathways to potentially predict the onset of metabolic dysfunction. 展开更多
关键词 Artificial intelligence Circadian rhythm Clock genes Diabetes mellitus magnetic resonance imaging Glymphatic pathway MITOCHONDRIA Oxidative stress Programmed cell death Sleep fragmentation
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Hydrogen sulfide reduces oxidative stress in Huntington's disease via Nrf2
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作者 Zige Jiang Dexiang Liu +7 位作者 Tingting Li Chengcheng Gai Danqing Xin Yijing Zhao Yan Song Yahong Cheng Tong Li Zhen Wang 《Neural Regeneration Research》 SCIE CAS 2025年第6期1776-1788,共13页
The pathophysiology of Huntington's disease involves high levels of the neurotoxin quinolinic acid. Quinolinic acid accumulation results in oxidative stress, which leads to neurotoxicity. However, the molecular an... The pathophysiology of Huntington's disease involves high levels of the neurotoxin quinolinic acid. Quinolinic acid accumulation results in oxidative stress, which leads to neurotoxicity. However, the molecular and cellular mechanisms by which quinolinic acid contributes to Huntington's disease pathology remain unknown. In this study, we established in vitro and in vivo models of Huntington's disease by administering quinolinic acid to the PC12 neuronal cell line and the striatum of mice, respectively. We observed a decrease in the levels of hydrogen sulfide in both PC12 cells and mouse serum, which was accompanied by down-regulation of cystathionine β-synthase, an enzyme responsible for hydrogen sulfide production. However, treatment with NaHS(a hydrogen sulfide donor) increased hydrogen sulfide levels in the neurons and in mouse serum, as well as cystathionine β-synthase expression in the neurons and the mouse striatum, while also improving oxidative imbalance and mitochondrial dysfunction in PC12 cells and the mouse striatum. These beneficial effects correlated with upregulation of nuclear factor erythroid 2-related factor 2 expression. Finally, treatment with the nuclear factor erythroid 2-related factor 2inhibitor ML385 reversed the beneficial impact of exogenous hydrogen sulfide on quinolinic acid-induced oxidative stress. Taken together, our findings show that hydrogen sulfide reduces oxidative stress in Huntington's disease by activating nuclear factor erythroid 2-related factor 2,suggesting that hydrogen sulfide is a novel neuroprotective drug candidate for treating patients with Huntington's disease. 展开更多
关键词 apoptosis CYSTATHIONINE-Β-SYNTHASE nuclear factor erythroid 2-related factor 2 Huntington's disease hydrogen sulfide MITOCHONDRION NEUROPLASTICITY oxidative stress quinolinic acid reactive oxygen species
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Effect of non-uniform stress characteristics on stress measurement in specimen 被引量:6
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作者 廖凯 吴运新 +2 位作者 龚海 闫鹏飞 郭俊康 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2010年第5期789-794,共6页
There is a remarkable difference in stress distribution between a specimen and a plate removed from the specimen.The plate presents a uniform stress distribution whereas the specimen presents a non-uniform stress dist... There is a remarkable difference in stress distribution between a specimen and a plate removed from the specimen.The plate presents a uniform stress distribution whereas the specimen presents a non-uniform stress distribution.Firstly,the real stress distributions in plates with thickness of 30,40 and 50 mm and then in the specimens were obtained through simulation and X-ray surface stress measurement.Secondly,in order to study the impact of specimens shapes and processing ways on the results accuracy,two irregular shapes (parallelogram and trapezoid) and two processing ways (saw and electron discharge machining (EDM)) were compared and analyzed by simulation and experiment using layer removal method,then the specimen effects on measurement results were evaluated.The results show that:1) the non-uniform stress distribution characteristics of the specimen near the surface of the cut is significant,the range of non-uniform stress distribution is approximately one-thickness distance away from the cut,and it decreases gradually along the depth;2) In order to ensure the stability in the results,it is suitable to take the specimen plane size 2-3 times of its thickness;3) Conventional processing methods have little effect on experimental results and the average deviation is less than 5%. 展开更多
关键词 SPECIMEN non-uniform characteristic layer removal method (LRM) stress distribution aluminum alloy plate
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Stress analytical solution for plane problem of a double-layered thick-walled cylinder subjected to a type of non-uniform distributed pressure 被引量:4
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作者 吴庆良 吕爱钟 +2 位作者 高永涛 吴顺川 张宁 《Journal of Central South University》 SCIE EI CAS 2014年第5期2074-2082,共9页
The stress state around circular openings,such as boreholes,shafts,and tunnels,is usually needed to be evaluated.Solutions for stresses,strains and ultimate bearing capacities of pressurized hollow cylinder are common... The stress state around circular openings,such as boreholes,shafts,and tunnels,is usually needed to be evaluated.Solutions for stresses,strains and ultimate bearing capacities of pressurized hollow cylinder are common cases.Stress analytical method for plane problem of a double-layered thick-walled cylinder subjected to a type of non-uniform pressure on the outer surface and uniform radial pressure on the inner surface is given.The power series method of complex function is used.The stress analytical solution is obtained with the assumption that two layers of a cylinder are fully contacted.The distributions of normal and tangential contact stress along the interface,tangential stress on the inner boundary and stresses in the radial direction at θ=0°,45° and 90°,are obtained.An example indicates that,when the elastic modulus of the inner layer of a double-layered thick-walled cylinder is smaller than that of the outer layer,the tangential stress is smaller than that in the corresponding point for a traditional cylinder composed of homogeneous materials.In that way,stress concentration at the inner surface can be alleviated and the stress distribution is more uniform.This is a capable way to enhance the elastic ultimate bearing capacity of thick-walled cylinder. 展开更多
关键词 thick-walled cylinder stress analytical solution complex variable function non-uniform distributed pressure stressconcentration combination of different elastic moduli
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Inverse approach to determine piston profile from impact stress waveform on given non-uniform rod 被引量:1
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作者 朱萍玉 刘德顺 +1 位作者 彭佑多 陈安华 《中国有色金属学会会刊:英文版》 CSCD 2001年第2期297-300,共4页
An essential problem in the design of mechanical impact systems is the impact of a piston on a rod. The impact of a semi finite cylindrical piston on a non uniform rod was studied. Based on wave mechanics and characte... An essential problem in the design of mechanical impact systems is the impact of a piston on a rod. The impact of a semi finite cylindrical piston on a non uniform rod was studied. Based on wave mechanics and characteristic line theory, an inverse numerical approach to determine the piston profile was proposed, by means of which the geometry of an impact piston may be determined from the given stress waveform for a given rod profile. Numerical results show that the given stress waveform may be produced by means of the alternatives of design of piston and rod. There is good agreement between the experimental results and numerical results. [ 展开更多
关键词 impact PISTON PROFILE non-uniform ROD INVERSE numerical approach stress WAVEFORM
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A well test model for stress-sensitive and heterogeneous reservoirs with non-uniform thicknesses 被引量:1
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作者 Zhang Liehui Guo Jingjing Liu Qiguo 《Petroleum Science》 SCIE CAS CSCD 2010年第4期524-529,共6页
In view of the anisotropy,heterogeneity and stress-sensitive permeability in low permeability reservoirs,an analytical well test model was established by introducing the concept of permeability modulus.This model cons... In view of the anisotropy,heterogeneity and stress-sensitive permeability in low permeability reservoirs,an analytical well test model was established by introducing the concept of permeability modulus.This model considered the permeability stress-sensitivity,wellbore storage effect,and the skin effect.The perturbation technique and Laplace transformation were used to solve the mathematical model analytically in Laplace space,and the bottom-hole pressure type curves were plotted and analyzed in real space by using the Stehfest numerical inversion. 展开更多
关键词 non-uniform thickness stress-sensitive heterogeneous reservoir transient well test type curve
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A novel wavy non-uniform ligament chiral stent with J-shaped stress-strain behavior to mimic the native trachea 被引量:2
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作者 Jiapeng Liu Xinhua Yao +4 位作者 Zhenwei Wang Jian Ye Congcong Luan Jianzhong Fu Yong He 《Bio-Design and Manufacturing》 SCIE EI CSCD 2021年第4期851-866,共16页
Tracheal stents are an important form of treatment for benign or malignant central airway obstruction.However,the mechanical behavior of current tracheal stents is significantly different from that of the native trach... Tracheal stents are an important form of treatment for benign or malignant central airway obstruction.However,the mechanical behavior of current tracheal stents is significantly different from that of the native trachea,which leads to a variety of serious complications.In this study,inspired by the structure of the native trachea,a wavy non-uniform ligament chiral tracheal stent is proposed,in which J-shaped stress-strain behavior and negative Poisson's ratio response are achieved by replacing the tangential ligament of tetrachiral and anti-tetrachiral hybrid structure with a wavy non-uniform ligament.Through the combination of theoretical analysis,finite element analysis and experimental tests,a wide range of desired J-shaped stress-strain curves are explored to mimic the native porcine trachea by tailoring the stent geometry.Besides,the negative Poisson’s ratio and auxetic diameter curves versus axial strain of the stent are also studied in detail,thus contributing to the enhancement of cross-section ventilation and reducing the migration of the stent.This novel tracheal stent with a unique microstructure shows a potential to perfectly match the physiological activities of the native trachea and thereby reduce potential complications. 展开更多
关键词 Tracheobronchial stenosis Tracheal stent Chiral auxetic structure Wavy non-uniform ligament J-shaped stress-strain behavior Negative Poisson’s ratio
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Numerical Study on Effect of Non-uniform CMAS Penetration on TGO Growth and Interface Stress Behavior of APS TBCs
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作者 Zhenwei Cai Zifan Zhang +2 位作者 Yingzheng Liu Xiaofeng Zhao Weizhe Wang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2021年第6期98-113,共16页
The penetration of CaO-MgO-Al_(2)O_(3)-SiO_(2)(CMAS)is one of the most significant factors that induce the failure of air-plasma-sprayed thermal barrier coatings(APS TBCs).The direct penetration of CMAS changes the th... The penetration of CaO-MgO-Al_(2)O_(3)-SiO_(2)(CMAS)is one of the most significant factors that induce the failure of air-plasma-sprayed thermal barrier coatings(APS TBCs).The direct penetration of CMAS changes the thermal/mechanical properties of the top coat(TC)layer,which affects the thermal mismatch stress behavior and the growth of thermally grown oxide(TGO)at the TC/bond coat(BC)interface,thereby resulting in a more complicated interface stress state.In the present study,a two-dimensional global model of APS TBCs with half of the TC layer penetrated by CMAS is established to investigate the effect of non-uniform CMAS penetration on the interface stress behavior.Subsequently,a local model extracted from the global model is established to investigate the effects of interface morphologies and CMAS penetration depth.The results show that non-uniform CMAS penetration causes non-uniform TGO growth in APS TBCs,which consequently causes the stress behavior to vary along the interface.Furthermore,the CMAS pen-etration depth imposes a significant effect on the TC/TGO interface stress behavior,whereas the interface roughness exerts a prominent effect on the stress level at the BC/TGO interface under CMAS penetration.This study reveals the mechanism associated with the effect of non-uniform CMAS penetration on the interface stress behavior in APS TBCSs. 展开更多
关键词 CMAS non-uniform penetration TGO growth Interface stress CMAS penetration depth Interface roughness
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Grain Yield,Biomass Accumulation,and Leaf Photosynthetic Characteristics of Rice under Combined Salinity-Drought Stress 被引量:2
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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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Non-uniform,axisymmetric misfit strain:in thin films bonded on plate substrates/substrate systems:the relation between non-uniform film stresses and system curvatures
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作者 Yonggang Huang D. Ngo A. J. Rosakis 《Acta Mechanica Sinica》 SCIE EI CAS CSCD 2005年第4期362-370,共9页
Current methodologies used for the inference of thin film stress through curvature measurements are strictly restricted to stress and curvature states which are assumed to remain uniform over the entire film/substrate... Current methodologies used for the inference of thin film stress through curvature measurements are strictly restricted to stress and curvature states which are assumed to remain uniform over the entire film/substrate system. By considering a circular thin film/substrate system subject to non-uniform, but axisymmetric misfit strain distributions in the thin film, we derived relations between the film stresses and the misfit strain, and between the plate system's curvatures and the misfit strain. These relations feature a “local” part which involves a direct dependence of the stress or curvature components on the misfit strain at the same point, and a “non-local” part which reflects the effect of misfit strain of other points on the location of scrutiny. Most notably, we also derived relations between the polar components of the film stress and those of system curvatures which allow for the experimental inference of such stresses from full-field curvature measurements in the presence of arbitrary radial non-uniformities. These relations also feature a “non-local” dependence on curvatures making a full-field measurement a necessity. Finally, it is shown that the interfacial shear tractions between the film and the substrate are proportional to the radial gradients of the first curvature invariant and can also be inferred experimentally. 展开更多
关键词 non-uniform misfit strain non-uniform wafer curvatures stress-curvature relations Non-local effects Interfacial shears
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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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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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