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Dynamic change of xylanase activity and gene expression during wheat germination on As(III) stress
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作者 LI Chun-xi LI Dan-dan SHAO Yun FENG Shu-li ZHANG Dai-jing ZHANG Bei-bei JIANG Li-na 《Journal of Life Sciences》 2008年第5期45-50,共6页
关键词 木聚糖酶基因 小麦胚芽 动态变化 活性 基因表达 发芽期间 半定量逆转录聚合酶链反应 培育方法
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共表达分子伴侣蛋白提高III型普鲁兰水解酶在短小芽孢杆菌中的分泌表达及发酵优化
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作者 曾静 郭建军 +1 位作者 王通 袁林 《食品工业科技》 CAS 北大核心 2024年第10期149-157,共9页
本研究旨在通过共表达分子伴侣蛋白以及优化发酵条件来提高III型普鲁兰水解酶(TK-PUL)在短小芽孢杆菌中的分泌表达水平。通过构建共表达TK-PUL和分子伴侣蛋白的多种重组短小芽孢杆菌,并以胞外酶活为指标对其进行筛选,确定最有利于TK-PU... 本研究旨在通过共表达分子伴侣蛋白以及优化发酵条件来提高III型普鲁兰水解酶(TK-PUL)在短小芽孢杆菌中的分泌表达水平。通过构建共表达TK-PUL和分子伴侣蛋白的多种重组短小芽孢杆菌,并以胞外酶活为指标对其进行筛选,确定最有利于TK-PUL分泌表达的分子伴侣蛋白及对应的重组短小芽孢杆菌。在此基础上采用单因素实验和响应面法优化重组短小芽孢杆菌的发酵条件。结果表明,共表达分子伴侣蛋白PrsA^(Ba)的重组短小芽孢杆菌的胞外酶活达到98.79 U/mL,提高了0.31倍。该重组短小芽孢杆菌的最佳培养基包括19.65 g/L葡萄糖、21.46 g/L酵母提取物、12.01 g/L MgCl_(2)·6H_(2)O、9.02 g/L脯氨酸、0.01 g/L FeSO4·7H_(2)O、0.01 g/L MnSO4·4H_(2)O、0.001 g/L ZnSO4·7H_(2)O。在发酵温度为35℃、起始发酵pH为7.0的条件下,该重组短小芽孢杆菌于最佳培养基中培养66 h时,其胞外酶活达到192.68 U/mL,提高了1.56倍。本研究通过共表达分子伴侣蛋白和发酵优化实现了TK-PUL在短小芽孢杆菌的高效分泌表达,为TK-PUL的应用提供了基础。 展开更多
关键词 iii型普鲁兰水解酶 短小芽孢杆菌 胞外分子伴侣蛋白 发酵优化 分泌表达
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混合牙列期骨性III类错合与骨性I类错合基骨及牙弓对比研究
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作者 盛丽 刘佳 《亚洲急诊医学病例研究》 2024年第1期23-30,共8页
目的:通过测量混合牙列期骨性III类错合患者与骨性I类错合患者的锥形束计算机断层扫描(Cone beam computed tomography, CBCT),对比分析上下颌牙弓、基骨弓长度与宽度差异及协调性,以期为替牙期骨性III类错合畸形治疗提供参考依据。方法... 目的:通过测量混合牙列期骨性III类错合患者与骨性I类错合患者的锥形束计算机断层扫描(Cone beam computed tomography, CBCT),对比分析上下颌牙弓、基骨弓长度与宽度差异及协调性,以期为替牙期骨性III类错合畸形治疗提供参考依据。方法:选择替牙列期骨性III类错合与骨性I类错合各30例,通过Dolphin软件处理收集到的DICOM (Digital Imaging and Communications in Medicine)医学图像数据,行三维重建并测量上下颌牙弓、基骨弓的长度与宽度,计算同一牙段牙弓宽度与基骨弓宽度之间的差值,比较骨性III类与骨性I类错牙合畸形牙弓与基骨弓宽度差值的差异。结果:1) 骨性III类错合组上颌牙弓及基骨弓长度均小于骨性I类错合组,下颌基骨弓长度大于骨性I类错合组,且差异有统计学意义(P 0.05)。2) 骨性III类错合组下颌前段及中段基骨弓宽度大于骨性I类错合组,差异有统计学意义(P 0.05)。3) 骨性III类错合组上颌牙弓与基骨弓宽度的差值均大于骨性I类错合组,下颌牙弓与基骨弓宽度的差值均小于骨性I类错合组,其中上颌后段牙弓宽度与基骨弓宽度差值差异有统计学意义(P < 0.05)。结论:混合牙列期骨性III类错合存在牙弓、基骨弓不调,上颌可扩大基骨弓,下颌可扩大牙弓,以期改善牙弓与基骨弓的协调性。 展开更多
关键词 混合牙列 骨性iii类错合 牙弓 基骨弓
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基于NSGA-III算法求解柔性作业车间调度问题
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作者 宋存利 朱建伟 李金泰 《机电工程技术》 2024年第5期11-15,85,共6页
针对多目标柔性作业车间调度问题,提出一种改进NSGA-Ⅲ算法,以完工时间、机器总负荷、瓶颈机器负荷为目标建立调度模型。首先,为提高种群的多样性,提出一种基于惩罚的边界相交距离定义关联操作中种群个体与参考向量之间的距离;其次,为... 针对多目标柔性作业车间调度问题,提出一种改进NSGA-Ⅲ算法,以完工时间、机器总负荷、瓶颈机器负荷为目标建立调度模型。首先,为提高种群的多样性,提出一种基于惩罚的边界相交距离定义关联操作中种群个体与参考向量之间的距离;其次,为提高环境选择的计算效率,利用基于惩罚的边界相交距离消除机制来保护个体,降低了个体保护策略的计算成本;最后,为避免种群陷入局部最优,在遗传算子中采用一种改进的变异策略。运用两个评价指标与NSGA-Ⅲ算法进行比较,其收敛性与多样性均由于NSGA-Ⅲ算法。同时在4个Kacem算例上进行测试得出改进NSGA-Ⅲ算法解的质量较高,最后通过实际的生产实例证明改进的NSGA-Ⅲ算法优于或等同于现存在的方法,也证明了该方法在解决多目标柔性作业车间调度难题上的可操作性。 展开更多
关键词 多目标柔性作业车间 NSGA-Ⅲ 变异策略 消除机制
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Ferroptosis and endoplasmic reticulum stress in ischemic stroke 被引量:3
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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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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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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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Heat stress induced hepatocyte apoptosis in largemouth bass Micropterus salmoides via IRE1α/TRAF2/ASK1/JNK pathway
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作者 Xuqian ZHAO Wenjia MAO +1 位作者 Zijie LIN Qufei LING 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第3期988-1000,共13页
Heat stress(HS)has been shown to adversely affect fish livers and can lead to extensive apoptosis.To investigate the relationship between endoplasmic reticulum(ER)stress and HS-induced apoptosis in fish livers,we isol... Heat stress(HS)has been shown to adversely affect fish livers and can lead to extensive apoptosis.To investigate the relationship between endoplasmic reticulum(ER)stress and HS-induced apoptosis in fish livers,we isolated and cultured primary hepatocytes of largemouth bass,Micropterus salmoides by trypsin method,then established an in-vitro model of liver cells under HS(35℃).The contents of lactic dehydrogenase(LDH)and hydrogen peroxide(H2O2)were determined to evaluate the effects of HS on hepatocyte injury and oxidative stress.RT-qPCR was performed to discover the key genes in unfolded protein response(UPR)pathways involved at different HS duration.ERS inhibitor 4-PBA and IRE1αinhibitor 4μ8C were used to further investigate the effects of HS on IRE1αapoptosis pathway in hepatocytes.Results show that HS led to significant increases in the release of LDH,the content of H2O2,and the expressions of oxidative protein folding genes(ero1αand pdi)under HS,suggesting severe hepatocyte injury and oxidative stress happened in heat-stressed largemouth bass hepatocytes.The continuous activation of IRE1αpathway genes(grp78,grp94,atf6,perk,eif2a,atf4,chop,ire1α,traf2,ask1,jnk1,and jnk2)indicated that HS led significantly to ER stress.In particular,the mRNA expression levels of ER stress-related genes(grp78,grp94,atf6,perk,ire1α,chop,jnk1,and jnk2)in the high temperature(HT)+4-PBA group and the HT+4μ8C group were significantly down-regulated under HS.After 4μ8C treatment,the expression levels of apoptosis-related genes(caspase-2,caspase-3,caspase-6,caspase-7,caspase-8,caspase-9,and caspase-10)and LDH content were significantly decreased,whereas the cell survival rate was significantly increased when given 4-PBA or 4μ8C treatment.These findings demonstrate that HS could induce liver apoptosis of largemouth bass through the IRE1αpathway,which may act as a key switch mediating liver apoptosis of largemouth bass under HS. 展开更多
关键词 heat stress Micropterus salmoides endoplasmic reticulum stress APOPTOSIS oxidative stress
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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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Biochanin A attenuates spinal cord injury in rats during early stages by inhibiting oxidative stress and inflammasome activation 被引量:1
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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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Stress tensor determination by modified hydraulic tests on pre-existing fractures:Method and stress constraints
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作者 Guiyun Gao Chenghu Wang Ke Gao 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第5期1637-1648,共12页
The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determinati... The hydraulic testing of pre-existing fractures(HTPF)is one of the most promising in situ stress measurement methods,particularly for three-dimensional stress tensor determination.However,the stress tensor determination based on the HTPF method requires at least six tests or a minimum of 14-15 tests(under different conditions)for reliable results.In this study,we modified the HTPF method by considering the shear stress on each pre-existing fracture,which increased the number of equations for the stress tensor determination and decreased the number of tests required.Different shear stresses were attributed to different fractures by random sampling;therefore,the stress tensors were obtained by searching for the optimal solution using the least squares criterion based on the Monte Carlo method.Thereafter,we constrained the stress tensor based on the tensile strength criterion,compressive strength criterion,and vertical stress constraints.The inverted stress tensors were presented and analyzed based on the tensorial nature of the stress using the Euclidean mean stress tensor.Two stress-measurement campaigns in Weifang(Shandong Province,China)and Mercantour road tunnel(France)were implemented to highlight the validity and efficiency of the modified HTPF(M-HTPF)method.The results showed that the M-HTPF method can be applied for stress tensor inversion using only three to four tests on pre-existing fractures,neglecting the stress gradient.The inversion results were confined to relatively small distribution dispersions and were significantly reliable and stable due to the shear stresses on the fractures and the stress constraints employed.The M-HTPF method is highly feasible and efficient for complete stress tensor determination in a single borehole. 展开更多
关键词 stress tensor Hydraulic tests on pre-existing fractures Mean stress stress constraint Hydraulic fracturing
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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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Neuron-to-astrocyte proteostatic stress signaling in response to tau pathology
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作者 Kevin Llewelyn Batenburg Wiep Scheper 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第3期505-506,共2页
Maintenance of protein homeostasis or“proteostasis”is essential for the functioning and viability of cells.This is in particular the case for cells like neurons that cannot self-renew and acquire unique functional p... Maintenance of protein homeostasis or“proteostasis”is essential for the functioning and viability of cells.This is in particular the case for cells like neurons that cannot self-renew and acquire unique functional properties during their lifetime.Cellular proteostatic stress responses are in place to protect cells from damage in case of proteostatic challenges.The integrated stress response(ISR)is one of the key proteostatic stress responses in the cell(Costa-Mattioli and Walter,2020).The ISR is the downstream convergence point for the four stress-induced eIF2αkinases(EIF2AK1-4)that control stress-regulated protein translation via phosphorylation of the translation factor eIF2α.ISR activation results in a transient reduction of global translation while it concomitantly enhances the translation of specific mRNAs,including that encoding the activating transcription factor 4(ATF4).Together,the translational control mediated by the ISR results in a temporary reduction of the overall protein load and the selectively increased expression of proteins that contribute to restoration of the proteostatic balance. 展开更多
关键词 TRANSLATION stress TOGETHER
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III型胶原蛋白在乳腺癌中的研究进展
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作者 刘潇蔚 明佳 《临床医学进展》 2024年第4期2295-2304,共10页
乳腺癌(Breast cancer, BC)于2020年在全球新增癌症病例成为了最常见癌症,且发病率逐年升高。胶原蛋白是构成细胞外基质(Extracellular Matrix, ECM)的主要成分,近年来的研究发现III型胶原蛋白(Collagen Type III, COLIII)在乳腺癌的发... 乳腺癌(Breast cancer, BC)于2020年在全球新增癌症病例成为了最常见癌症,且发病率逐年升高。胶原蛋白是构成细胞外基质(Extracellular Matrix, ECM)的主要成分,近年来的研究发现III型胶原蛋白(Collagen Type III, COLIII)在乳腺癌的发生、发展过程中发挥重要作用,并对肿瘤微环境(Tumor micro-environment, TME)的维持有重要意义。其中,癌症相关成纤维细胞(Cancer-associated fibroblasts, CAFs)在建立和重塑ECM结构中扮演关键角色,调控肿瘤细胞通过TME入侵的进程。但由于该体系庞大,通过分泌细胞因子和趋化因子与癌细胞相互作用的机制复杂,各成分及其亚型在癌症进展中的角色尚存争议。本文基于TME在乳腺恶性肿瘤中的研究现状以及作为ECM中重要成分的COLIII的性质结构、形态分布,分析COLIII通过改变ECM的机械力与刚度影响乳腺癌行为的机制,同时充分讨论特殊结构、来源的COLIII在微环境中的不同功能及作用方式,评估其应用于癌症治疗的可能性。 展开更多
关键词 iii型胶原蛋白 乳腺癌 细胞外基质 肿瘤微环境 癌症相关成纤维细胞
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