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Involvement of the ABA-and H_(2)O_(2)-Mediated Ascorbate-Glutathione Cycle in the Drought Stress Responses of Wheat Roots
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作者 Mengyuan Li Zhongye Gao +2 位作者 Lina Jiang Leishan Chen Jianhui Ma 《Phyton-International Journal of Experimental Botany》 SCIE 2024年第2期329-342,共14页
Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and th... Abscisic acid(ABA),hydrogen peroxide(H_(2)O_(2)) and ascorbate(AsA)–glutathione(GSH)cycle are widely known for their participation in various stresses.However,the relationship between ABA and H_(2)O_(2) levels and the AsA–GSH cycle under drought stress in wheat has not been studied.In this study,a hydroponic experiment was conducted in wheat seedlings subjected to 15%polyethylene glycol(PEG)6000–induced dehydration.Drought stress caused the rapid accumulation of endogenous ABA and H_(2)O_(2) and significantly decreased the number of root tips compared with the control.The application of ABA significantly increased the number of root tips,whereas the application of H_(2)O_(2) markedly reduced the number of root tips,compared with that under 15%PEG-6000.In addition,drought stress markedly increased the DHA,GSH and GSSG levels,but decreased the AsA levels,AsA/DHA and GSH/GSSG ratios compared with those in the control.The activities of the four enzymes in the AsA–GSH cycle were also markedly increased under drought stress,including glutathione reductase(GR),ascorbate peroxidase(APX),monodehydroascorbate reductase(MDHAR)and dehydroascorbate reductase(DHAR),compared with those in the control.However,the application of an ABA inhibitor significantly inhibited GR,DHAR and APX activities,whereas the application of an H_(2)O_(2) inhibitor significantly inhibited DHAR and MDHAR activities.Furthermore,the application of ABA inhibitor significantly promoted the increases of H_(2)O_(2) and the application of H_(2)O_(2) inhibitor significantly blocked the increases of ABA,compared with those under 15% PEG-6000.Taken together,the results indicated that ABA and H_(2)O_(2) probably interact under drought stress in wheat;and both of them can mediate drought stress by modulating the enzymes in AsA–GSH cycle,where ABA acts as the main regulator of GR,DHAR,and APX activities,and H_(2)O_(2) acts as the main regulator of DHAR and MDHAR activities. 展开更多
关键词 ABA H_(2)O_(2) AsA-GSH cycle drought stress wheat roots
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Ascorbate-Glutathione Cycle Alteration in Cadmium Sensitive Rice Mutant cadB-1 被引量:1
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作者 SHEN Guo-ming ZHU Cheng +1 位作者 DU Qi-zhen SHANGGUAN Li-na 《Rice science》 SCIE 2012年第3期185-192,共8页
A rice cadmium (Cd) sensitive mutant cadB-1 was obtained using Agrobacterium tumefaciens mediated system.After exposure of cadB-1 and wild type (WT) rice seedlings to a range of Cd concentrations for 10 d,Cd accumulat... A rice cadmium (Cd) sensitive mutant cadB-1 was obtained using Agrobacterium tumefaciens mediated system.After exposure of cadB-1 and wild type (WT) rice seedlings to a range of Cd concentrations for 10 d,Cd accumulated to higher levels in roots,stems and leaves of both cadB-1 and WT with increasing external Cd concentrations,and the inhibition of seedling growth in cadB-1 was more serious than in WT.Hydrogen peroxide accumulation was higher in leaves and roots of cadB-1.The ratios of reduced glutathione (GSH)/oxidized glutathione (GSSG),ascorbate (ASC)/dehydroascorbate (DHA) and reduced nicotinamide adenine dinucleotide phosphate (NADPH)/oxidized nicotinamide adenine dinucleotide phosphate (NADP+) were lower in cadB-1 than in WT both in leaves and roots under high Cd levels.The activities of ascorbate peroxidase (APX),glutathione peroxidase (GR),dehydroascorbate reductase (DHAR) and monodehydroascorbate reductase (MDHAR) were also lower in cadB-1 than in WT both in leaves and roots under the treatment of high levels of Cd.Our results suggest that under Cd stress,the ASC-GSH cycle was more seriously inhibited in cadB-1 than in WT,indicating that the mutant cadB-1 is less able to scavenge reactive oxygen species and sensitive to Cd. 展开更多
关键词 脱氢抗坏血酸还原酶 还原型谷胱甘肽 镉(CD) 水稻幼苗 突变体 还原型烟酰胺腺嘌呤二核苷酸 发行 敏感
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有向图上基于层次树索引的最大cycle truss社区搜索
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作者 宗传玉 张纯鹤 夏秀峰 《计算机应用》 CSCD 北大核心 2024年第1期190-198,共9页
社区搜索旨在从信息网络中找出包含用户查询顶点的高内聚连通子图,cycle truss是一种基于cycle三角形的社区搜索模型,而现有的基于索引的cycle truss社区搜索方法存在索引空间大、搜索效率低、社区内聚性低的缺点。为了解决这一问题,提... 社区搜索旨在从信息网络中找出包含用户查询顶点的高内聚连通子图,cycle truss是一种基于cycle三角形的社区搜索模型,而现有的基于索引的cycle truss社区搜索方法存在索引空间大、搜索效率低、社区内聚性低的缺点。为了解决这一问题,提出一种基于层次树索引的最大cycle truss社区搜索方法。首先,提出了k-cycle truss分解算法,并引入了两个重要的概念:cycle三角连通与k-层次等价。基于k-层次等价设计了层次树索引TreeCIndex与表结构索引SuperTable,在此基础上,并基于这两个新的索引,提出了两个高效的cycle truss社区搜索算法。在4个真实数据集上与已有的基于TrussIndex与EquiTruss的社区搜索算法进行了比较,实验结果表明,TreeCIndex与SuperTable比TrussIndex与EquiTruss节省至少41.5%的空间,索引构建的时间节省8.2%至98.3%,且搜索最大cycle truss社区的效率分别高出了一个和两个数量级。 展开更多
关键词 有向图 社区搜索 cycle truss cycle三角形 层次等价 层次树索引
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The Impact of Network Topologies and Radio Duty Cycle Mechanisms on the RPL Routing Protocol Power Consumption
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作者 Amal Hkiri Hamzah Faraj +3 位作者 Omar Ben Bahri Mouna Karmani Sami Alqurashi MohsenMachhout 《Computers, Materials & Continua》 SCIE EI 2024年第5期1835-1854,共20页
The Internet of Things(IoT)has witnessed a significant surge in adoption,particularly through the utilization of Wireless Sensor Networks(WSNs),which comprise small internet-connected devices.These deployments span va... The Internet of Things(IoT)has witnessed a significant surge in adoption,particularly through the utilization of Wireless Sensor Networks(WSNs),which comprise small internet-connected devices.These deployments span various environments and offer a multitude of benefits.However,the widespread use of battery-powered devices introduces challenges due to their limited hardware resources and communication capabilities.In response to this,the Internet Engineering Task Force(IETF)has developed the IPv6 Routing Protocol for Low-power and Lossy Networks(RPL)to address the unique requirements of such networks.Recognizing the critical role of RPL in maintaining high performance,this paper proposes a novel approach to optimizing power consumption.Specifically,it introduces a developed sensor motes topology integrated with a Radio Duty Cycling(RDC)mechanism aimed at minimizing power usage.Through rigorous analysis,the paper evaluates the power efficiency of this approach through several simulations conducted across different network topologies,including random,linear,tree,and elliptical topologies.Additionally,three distinct RDC mechanisms—CXMAC,ContikiMAC,and NullRDC—are investigated to assess their impact on power consumption.The findings of the study,based on a comprehensive and deep analysis of the simulated results,highlight the efficiency of ContikiMAC in power conservation.This research contributes valuable insights into enhancing the energy efficiency of RPL-based IoT networks,ultimately facilitating their widespread deployment and usability in diverse environments. 展开更多
关键词 WSN IoT radio duty cycles TOPOLOGIES
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Dynamic simulation analysis of molten salt reactor-coupled air-steam combined cycle power generation system
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作者 Jing-Lei Huang Guo-Bin Jia +3 位作者 Li-Feng Han Wen-Qian Liu Li Huang Zheng-Han Yang 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期222-233,共12页
A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the mol... A nonlinear dynamic simulation model based on coordinated control of speed and flow rate for the molten salt reactor and combined cycle systems is proposed here to ensure the coordination and stability between the molten salt reactor and power system.This model considers the impact of thermal properties of fluid variation on accuracy and has been validated with Simulink.This study reveals the capability of the control system to compensate for anomalous situations and maintain shaft stability in the event of perturbations occurring in high-temperature molten salt tank outlet parameters.Meanwhile,the control system’s impact on the system’s dynamic characteristics under molten salt disturbance is also analyzed.The results reveal that after the disturbance occurs,the controlled system benefits from the action of the control,and the overshoot and disturbance amplitude are positively correlated,while the system power and frequency eventually return to the initial values.This simulation model provides a basis for utilizing molten salt reactors for power generation and maintaining grid stability. 展开更多
关键词 Molten salt reactor Combined cycle Dynamic characteristic CONTROL
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Jovian Planet Influence on the Forcing of Sunspot Cycles
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作者 Fred J. Cadieu 《World Journal of Condensed Matter Physics》 CAS 2024年第1期1-9,共9页
The history of our solar system has been greatly influenced by the fact that there is a large gas giant planet, Jupiter that has a nearly circular orbit. This has allowed relics of the early solar system formation to ... The history of our solar system has been greatly influenced by the fact that there is a large gas giant planet, Jupiter that has a nearly circular orbit. This has allowed relics of the early solar system formation to still be observable today. Since Jupiter orbits the Sun with a period of approximately 12 years, it has always been thought that this could be connected to the nearly 11-year periodic peak in the number of sunspots observed. In this paper, the Sun and planets are considered to be moving about a center of mass point as the different planets orbit the Sun. This is the action of gravity that holds the solar system together. The center of mass for the Jupiter-Sun system actually lies outside the Sun. The four gas giant planets dominate such effects and the four gas giant Jovian planets can be projected together to determine an effective distance from the Sun’s center. Taken together these effects do seem to function as a sunspot forcing factor with a periodicity very close to 11 years. These predictions are made without consideration of any details of what is happening in the interior of the Sun. From these estimates, sunspot cycle 25 will be expected to peak in about September-October of 2025. Sunspot cycle 26 should peak in the year March of 2037. 展开更多
关键词 Sun cycles Solar System Formation JUPITER
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Hydrangea serrata extract exerts tumor inhibitory activity against hepatocellular carcinoma HepG2 cells via inducing p27/CDK2-mediated cell cycle arrest and apoptosis
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作者 Ye-eun Kim Jeonghye Hwang Ki-Young Kim 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第2期65-72,I0002-I0005,共12页
Objective:To examine the inhibitory effect of Hydrangea serrata extract against hepatocellular carcinoma HepG2 cells and its underlying mechanisms.Methods:The effects of Hydrangea serrata extract on growth inhibition ... Objective:To examine the inhibitory effect of Hydrangea serrata extract against hepatocellular carcinoma HepG2 cells and its underlying mechanisms.Methods:The effects of Hydrangea serrata extract on growth inhibition of tumor cells and spheroids were assessed using MTT and 3D culture assays.Quantitative real-time PCR and Western blot analyses were employed to investigate the changes in mRNA and protein expression levels of molecules related to cell cycle and apoptosis.Results:Hydrangea serrata extract effectively inhibited the growth of both tumor cells and spheroids.The extract also significantly upregulated p27 mRNA expression and downregulated CDK2 mRNA expression,leading to cell cycle arrest.Moreover,increased BAX/Bcl-2 ratio as well as caspase-9 and-3 were observed after treatment with Hydrangea serrata extract,indicating the induction of tumor cell apoptosis.Conclusions:Hydrangea serrata extract has the potential to alleviate tumors by effectively modulating cell-cycle-related gene expressions and inducing apoptosis,thereby inhibiting tumor growth. 展开更多
关键词 Hydrangea serrata Hepatocellular carcinoma Liver cancer Anticancer Cell cycle arrest APOPTOSIS
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Dual‑Atom Nanozyme Eye Drops Attenuate Inflammation and Break the Vicious Cycle in Dry Eye Disease
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作者 Dandan Chu Mengyang Zhao +8 位作者 Shisong Rong Wonho Jhe Xiaolu Cai Yi Xiao Wei Zhang Xingchen Geng Zhanrong Li Xingcai Zhang Jingguo Li 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第6期439-457,共19页
Dry eye disease(DED)is a major ocular pathology worldwide,causing serious ocular discomfort and even visual impairment.The incidence of DED is gradually increasing with the highfrequency use of electronic products.Alt... Dry eye disease(DED)is a major ocular pathology worldwide,causing serious ocular discomfort and even visual impairment.The incidence of DED is gradually increasing with the highfrequency use of electronic products.Although inflammation is core cause of the DED vicious cycle,reactive oxygen species(ROS)play a pivotal role in the vicious cycle by regulating inflammation from upstream.Therefore,current therapies merely targeting inflammation show the failure of DED treatment.Here,a novel dual-atom nanozymes(DAN)-based eye drops are developed.The antioxidative DAN is successfully prepared by embedding Fe and Mn bimetallic single-atoms in N-doped carbon material and modifying it with a hydrophilic polymer.The in vitro and in vivo results demonstrate the DAN is endowed with superior biological activity in scavenging excessive ROS,inhibiting NLRP3 inflammasome activation,decreasing proinflammatory cytokines expression,and suppressing cell apoptosis.Consequently,the DAN effectively alleviate ocular inflammation,promote corneal epithelial repair,recover goblet cell density and tear secretion,thus breaking the DED vicious cycle.Our findings open an avenue to make the DAN as an intervention form to DED and ROSmediated inflammatory diseases. 展开更多
关键词 Dry eye disease DAN Dual-atom nanozyme Vicious cycle NLRP3 inflammasome NANOMEDICINE
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Coupling Effect of Cryogenic Freeze-Thaw Cycles and Chloride Ion Erosion Effect in Pre-Cracked Reinforced Concrete
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作者 Yang Li Sibo Jiang Ruixin Lan 《Structural Durability & Health Monitoring》 EI 2024年第3期255-276,共22页
Chloride (Cl−) ion erosion effects can seriously impact the safety and service life of marine liquefied natural gas(LNG) storage tanks and other polar offshore structures. This study investigates the impact of differe... Chloride (Cl−) ion erosion effects can seriously impact the safety and service life of marine liquefied natural gas(LNG) storage tanks and other polar offshore structures. This study investigates the impact of different low-temperaturecycles (20°C, –80°C, and −160°C) and concrete specimen crack widths (0, 0.3, and 0.6 mm) on the Cl−ion diffusion performance through rapid erosion tests conducted on pre-cracked concrete. The results show thatthe minimum temperature and crack width of freeze-thaw cycles enhance the erosive effect of chloride ions. TheCl− ion concentration and growth rate increased with the increasing crack width. Based on the experimental modeland in accordance with Fick’s second law of diffusion, the Cl− ion diffusion equation was modified by introducingcorrection factors in consideration of the freeze-thaw temperature, crack width, and their coupling effect.The experimental and fitting results obtained from this model can provide excellent reference for practical engineeringapplications. 展开更多
关键词 Chloride ions freeze-thaw cycles cracks
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Clinical Practice of Evidence-Based PDCA Cycle Management Model in Accelerated Recovery of Lung Cancer Patients
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作者 Lu Kang Juan Yuan +1 位作者 Dandan Liu Bo Deng 《Journal of Cancer Therapy》 2024年第4期130-140,共11页
Objective: To explore the nursing effect of evidence-based PDCA cycle management mode in accelerated rehabilitation of patients undergoing thoracoscopic lung cancer radical surgery. Methods: 104 patients who underwent... Objective: To explore the nursing effect of evidence-based PDCA cycle management mode in accelerated rehabilitation of patients undergoing thoracoscopic lung cancer radical surgery. Methods: 104 patients who underwent thoracoscopic lung cancer radical surgery in our hospital from June 2022 to February 2023 were randomly divided into control group and intervention group, with 52 cases in each group. The control group implemented evidence-based ERAS clinical pathway management, while the intervention group implemented evidence-based PDCA cycle quality management. The postoperative recovery of the two groups of patients was compared. Results: The postoperative recovery of the intervention group was significantly better than that of the control group. The first time to get out of bed, the first time to eat, the duration of chest drainage tube placement, and the length of hospital stay were significantly shorter than those of the control group. The incidence of postoperative chest complications and hospitalization costs were significantly lower than those of the control group, and patient satisfaction was significantly higher than that of the control group (P Conclusion: Evidence-based PDCA cycle quality management mode can effectively improve the implementation quality of accelerated rehabilitation nursing for patients undergoing thoracoscopic lung cancer radical surgery, and it is worthy of clinical promotion. 展开更多
关键词 EVIDENCE-BASED PDCA cycle Thoracoscopic Lung Cancer Radical Surgery Accelerated Rehabilitation
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Repair of Second-Generation Recycled Fine Aggregate of Waste Concrete from Freeze-Thaw Environment by Carbonation Treatment
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作者 Jie Huang Rongbin Jiang +1 位作者 Xiaobo Sun Yingyong Shuai 《Journal of Renewable Materials》 EI CAS 2024年第1期187-201,共15页
The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of construction.This study investigated the repair effect of carbonation treatment on second-generation recycled ... The reuse of waste recycled concrete from harsh environments has become a research hotspot in the field of construction.This study investigated the repair effect of carbonation treatment on second-generation recycled fine aggregate(SRFA)obtained from recycled fine aggregate concrete(RFAC)subjected to freeze-thaw(FT)cycles.Before and after carbonation,the properties of SRFA were evaluated.Carbonated second-generation recycled fine aggregate(CSRFA)at five substitution rates(0%,25%,50%,75%,100%)to replace SRFA was used to prepare carbonated second-generation recycled fine aggregate concrete(CSRFAC).The water absorption,porosity and mechanical properties of CSRFAC were tested,and its frost-resisting durability was evaluated.The results showed after carbonation treatment,the physical properties of SRFA was improved and met the requirements of II aggregate.The micro-hardness of the interfacial transition zone and attached mortar in CSRFA was 50.5%and 31.2%higher than that in SRFA,respectively.With the increase of CSRFA replacement rate,the water absorption and porosity of CSRFAC gradually decreased,and the mechanical properties and frost resistance of CSRFAC were gradually improved.Carbonation treatment effectively repairs the damage of SRFA caused by FT cycles and improves its application potential. 展开更多
关键词 Carbonation treatment REPAIR freeze-thaw cycles second-generation recycled fine aggregate
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Effect of drying-wetting cycles on pore characteristics and mechanical properties of enzyme-induced carbonate precipitation-reinforced sea sand
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作者 Ming Huang Kai Xu +2 位作者 Zijian Liu Chaoshui Xu Mingjuan Cui 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期291-302,共12页
Enzyme-induced carbonate precipitation(EICP)is an emanating,eco-friendly and potentially sound technique that has presented promise in various geotechnical applications.However,the durability and microscopic character... Enzyme-induced carbonate precipitation(EICP)is an emanating,eco-friendly and potentially sound technique that has presented promise in various geotechnical applications.However,the durability and microscopic characteristics of EICP-treated specimens against the impact of drying-wetting(D-W)cycles is under-explored yet.This study investigates the evolution of mechanical behavior and pore charac-teristics of EICP-treated sea sand subjected to D-W cycles.The uniaxial compressive strength(UCS)tests,synchrotron radiation micro-computed tomography(micro-CT),and three-dimensional(3D)recon-struction of CT images were performed to study the multiscale evolution characteristics of EICP-reinforced sea sand under the effect of D-W cycles.The potential correlations between microstructure characteristics and macro-mechanical property deterioration were investigated using gray relational analysis(GRA).Results showed that the UCS of EICP-treated specimens decreases by 63.7% after 15 D-W cycles.The proportion of mesopores gradually decreases whereas the proportion of macropores in-creases due to the exfoliated calcium carbonate with increasing number of D-W cycles.The micro-structure in EICP-reinforced sea sand was gradually disintegrated,resulting in increasing pore size and development of pore shape from ellipsoidal to columnar and branched.The gray relational degree suggested that the weight loss rate and UCS deterioration were attributed to the development of branched pores with a size of 100-1000 m m under the action of D-W cycles.Overall,the results in this study provide a useful guidancee for the long-term stability and evolution characteristics of EICP-reinforced sea sand under D-W weathering conditions. 展开更多
关键词 Enzyme-induced carbonate precipitation(EICP) Plant-based urease Drying-wetting(D-W)cycles Microstructure
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Summer Atmospheric Water Cycle under the Transition Influence of the Westerly and Summer Monsoon over the Yarlung Zangbo River Basin in the Southern Tibetan Plateau
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作者 Qianhui MA Chunyan ZHANG +1 位作者 Donghai WANG Zihao PANG 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2024年第5期830-846,共17页
This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan Plateau.The ... This study compares the summer atmospheric water cycle,including moisture sources and consumption,in the upstream,midstream,and downstream regions of the Yarlung Zangbo River Basin in the southern Tibetan Plateau.The evolutions of moisture properties under the influence of the westerly and summer southerly monsoon are examined using 5-yr multi-source measurements and ERA5 reanalysis data.Note that moisture consumption in this study is associated with clouds,precipitation,and diabatic heating.Compared to the midstream and downstream regions,the upstream region has less moisture,clouds,and precipitation,where the moisture is brought by the westerly.In early August,the vertical wet advection over this region becomes enhanced and generates more high clouds and precipitation.The midstream region has moisture carried by the westerly in June and by the southerly monsoon from July to August.The higher vertical wet advection maximum here forms more high clouds,with a precipitation peak in early July.The downstream region is mainly affected by the southerly-driven wet advection.The rich moisture and strong vertical wet advection here produce the most clouds and precipitation among the three regions,with a precipitation peak in late June.The height of the maximum moisture condensation is different between the midstream region(325 hPa)and the other two regions(375 hPa),due to the higher upward motion maximum in the midstream region.The diabatic heating structures show that stratiform clouds dominate the upstream region,stratiform clouds and deep convection co-exist in the midstream region,and deep convection systems characterize the downstream region. 展开更多
关键词 Yarlung Zangbo River Basin atmospheric water cycle constrained variational analysis moisture source and consumption
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Multi-objective optimization and evaluation of supercritical CO_(2) Brayton cycle for nuclear power generation
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作者 Guo-Peng Yu Yong-Feng Cheng +1 位作者 Na Zhang Ping-Jian Ming 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2024年第2期183-209,共27页
The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayto... The supercritical CO_(2) Brayton cycle is considered a promising energy conversion system for Generation IV reactors for its simple layout,compact structure,and high cycle efficiency.Mathematical models of four Brayton cycle layouts are developed in this study for different reactors to reduce the cost and increase the thermohydraulic performance of nuclear power generation to promote the commercialization of nuclear energy.Parametric analysis,multi-objective optimizations,and four decision-making methods are applied to obtain each Brayton scheme’s optimal thermohydraulic and economic indexes.Results show that for the same design thermal power scale of reactors,the higher the core’s exit temperature,the better the Brayton cycle’s thermo-economic performance.Among the four-cycle layouts,the recompression cycle(RC)has the best overall performance,followed by the simple recuperation cycle(SR)and the intercooling cycle(IC),and the worst is the reheating cycle(RH).However,RH has the lowest total cost of investment(C_(tot))of$1619.85 million,and IC has the lowest levelized cost of energy(LCOE)of 0.012$/(kWh).The nuclear Brayton cycle system’s overall performance has been improved due to optimization.The performance of the molten salt reactor combined with the intercooling cycle(MSR-IC)scheme has the greatest improvement,with the net output power(W_(net)),thermal efficiencyη_(t),and exergy efficiency(η_(e))improved by 8.58%,8.58%,and 11.21%,respectively.The performance of the lead-cooled fast reactor combined with the simple recuperation cycle scheme was optimized to increase C_(tot) by 27.78%.In comparison,the internal rate of return(IRR)increased by only 7.8%,which is not friendly to investors with limited funds.For the nuclear Brayton cycle,the molten salt reactor combined with the recompression cycle scheme should receive priority,and the gas-cooled fast reactor combined with the reheating cycle scheme should be considered carefully. 展开更多
关键词 Supercritical CO_(2)Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods
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Research into Applicability of Wöhler Curve Method for Low-Cycle Fatigue of Metallic Materials
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作者 Xiangqiao Yan 《Journal of Harbin Institute of Technology(New Series)》 CAS 2024年第2期22-37,共16页
Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important... Recently,a description on a practicability of the Wöhler Curve Method for low-cycle fatigue of metals was given by the author.By the description and the low cycle fatigue test data of 16 MnR steel,it is important to show that,for low cycle fatigue of metals,such a way that a stress-based intensity parameter calculated by the linear-elastic analysis is taken to be a stress intensity parameter,S,to establish a relationship between the stress intensity parameter,S,and the fatigue life,N,is practicable.In this paper,many metallic materials from the literature are given to show that the Wöhler Curve Method is well suitable for low-cycle fatigue analysis of metals. 展开更多
关键词 low cycle fatigue Wöhler curve method coffin-manson curve method METALS
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Heteroclinic Cycles in a Class of 3-Dimensional Piecewise Affine Systems
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作者 Minghao Liu Ruimin Liu 《Journal of Applied Mathematics and Physics》 2024年第2期488-508,共21页
This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and ... This paper explores the existence of heteroclinic cycles and corresponding chaotic dynamics in a class of 3-dimensional two-zone piecewise affine systems. Moreover, the heteroclinic cycles connect two saddle foci and intersect the switching manifold at two points and the switching manifold is composed of two perpendicular planes. 展开更多
关键词 Piecewise Affine System Heteroclinic cycle Chaotic Invariant Set
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Statistical Study of the Geoeffectivity of Halo Coronal Mass Ejections Associated with X-Class Flares during Solar Cycles 23 and 24
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作者 Younoussa Diakite Christian Zoundi +1 位作者 M’Bi Kabore Jean Louis Zerbo 《Open Journal of Applied Sciences》 2024年第4期950-960,共11页
By analysing a long series of data (1996-2019), we show that solar cycle 23 was more marked by violent solar flares and coronal mass ejections (CMEs) compared to solar cycle 24. In particular, the halo coronal mass ej... By analysing a long series of data (1996-2019), we show that solar cycle 23 was more marked by violent solar flares and coronal mass ejections (CMEs) compared to solar cycle 24. In particular, the halo coronal mass ejections associated with X-class flares appear to be among the most energetic events in solar activity given the size of the flares, the speed of the CMEs and the intense geomagnetic storms they produce. Out of eighty-six (86) X-class halo CMEs, thirty-seven (37) or 43% are highly geoeffective;twenty-four (24) or approximately 28% are moderately geoeffective and twenty-five (25) or 29% are not geoeffective. Over the two solar cycles (1996 to 2019), 71% of storms were geoeffective and 29% were not. For solar cycle 23, about 78% of storms were geoeffective, while for solar cycle 24, about 56% were geoeffective. For the statistical study based on speed, 85 halo CMEs associated with X-class flares were selected because the CME of 6 December 2006 has no recorded speed value. For both solar cycles, 75.29% of the halo CMEs associated with X-class flares have a speed greater than 1000 km/s. The study showed that 42.18% of halo (X) CMEs with speeds above 1000 km/s could cause intense geomagnetic disturbances. These results show the contribution (in terms of speed) of each class of halo (X) CMEs to the perturbation of the Earth’s magnetic field. Coronal mass ejections then become one of the key indicators of solar activity, especially as they affect the Earth. 展开更多
关键词 CME Halo (X) Geoeffectivity Geomagnetic Storm Solar Flare Solar cycle
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Numerical Models and Methods of Atmospheric Parameters Originating in the Formation of the Earth’s Climatic Cycle
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作者 Wend Dolean Arsène Ilboudo Kassoum Yamba +1 位作者 Windé Nongué Daniel Koumbem Issaka Ouédraogo 《Atmospheric and Climate Sciences》 2024年第2期277-286,共10页
Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model o... Atmospheric models are physical equations based on the ideal gas law. Applied to the atmosphere, this law yields equations for water, vapor (gas), ice, air, humidity, dryness, fire, and heat, thus defining the model of key atmospheric parameters. The distribution of these parameters across the entire planet Earth is the origin of the formation of the climatic cycle, which is a normal climatic variation. To do this, the Earth is divided into eight (8) parts according to the number of key parameters to be defined in a physical representation of the model. Following this distribution, numerical models calculate the constants for the formation of water, vapor, ice, dryness, thermal energy (fire), heat, air, and humidity. These models vary in complexity depending on the indirect trigonometric direction and simplicity in the sum of neighboring models. Note that the constants obtained from the equations yield 275.156˚K (2.006˚C) for water, 273.1596˚K (0.00963˚C) for vapor, 273.1633˚K (0.0133˚C) for ice, 0.00365 in/s for atmospheric dryness, 1.996 in<sup>2</sup>/s for humidity, 2.993 in<sup>2</sup>/s for air, 1 J for thermal energy of fire, and 0.9963 J for heat. In summary, this study aims to define the main parameters and natural phenomena contributing to the modification of planetary climate. . 展开更多
关键词 Atmospheric Parameter 1 Climatic cycle 2 Numerical Models 3
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Application of PDCA Cycle in Hand Hygiene Management of Psychiatric Medical Staff
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作者 Li Xiang Weidong Liu +1 位作者 Guiying Chen Mei Liu 《Journal of Clinical and Nursing Research》 2024年第3期152-157,共6页
Objective:To study the application effect of the plan-do-check-act(PDCA)cycle management in the hand hygiene management of psychiatric medical staff.Methods:One hundred and twenty medical staff from a psychiatric hosp... Objective:To study the application effect of the plan-do-check-act(PDCA)cycle management in the hand hygiene management of psychiatric medical staff.Methods:One hundred and twenty medical staff from a psychiatric hospital from May 2023 to December 2023 were selected and divided into two groups.The control group(May 2023 to August 2023)applied the conventional management model,and the observation group(September 2023 to December 2023)applied the PDCA cycle management.The hand hygiene compliance,hand hygiene knowledge,and hygiene qualifications were compared,including the amount of hand sanitizer used.Results:The proportion of medical staff’s hand hygiene compliance and hand hygiene knowledge mastery scores in the observation group were higher than those in the control group(P<0.05);the hand hygiene passing rate in the observation group was higher than that of the control group(P<0.05);the daily amount of hand sanitizer per patient bed and the amount of hand sanitizer used was higher than that of the control group(P<0.05).Conclusion:The PDCA cycle management model for psychiatric medical staff promoted the improvement of hand hygiene compliance and increased their hand hygiene qualifications.It is suitable for further popularization and application in future clinical practice. 展开更多
关键词 PSYCHIATRY PDCA cycle management Hand hygiene management COMPLIANCE
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Conjuncture Cycles and Monetary Anomalies Are Unwelcome Guests for Sustainability
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作者 Giovanni Antonio Cossiga 《Economics World》 2024年第1期1-16,共16页
Economic cycles are not economic evils but rather healing agents for returning to equilibrium,just as inflation and deflation are not economic misfortunes but the sign of bad governance and a bitter medicine for retur... Economic cycles are not economic evils but rather healing agents for returning to equilibrium,just as inflation and deflation are not economic misfortunes but the sign of bad governance and a bitter medicine for returning to calm monetary.Unfortunately,signs of poor governance are mistaken for unfortunate events,but are instead tools offered to restore economic systems.Politics seeks consensus and does not accept the bitter cure of recession.Monetary policy is therefore called into question even if monetary anomalies also depend on errors in the management of the economy;the result is the gradual increase in interest rates.Is the idea that we can achieve the goal of complete neutrality with nature acceptable in a global economic framework pervaded by inflation and denunciation?Can we similarly argue that economic problems can coexist once the goal of neutrality has been achieved?The answer is negative.We must correct these anomalies and dysfunctions of the economy,which cannot coexist in the new context of complete and indefinite equilibrium of tomorrow.And not even the idea that conflicts can be resolved with war seems to find a place in the renewed scenario of neutrality.In this regard we can remember that,when we have reached the economic optimum of complete neutrality,or at least we are close to it,the most socially and economically advanced territories and continents will benefit from an acceleration of productivity and development.Scarcity itself will give way to the new,long-awaited reality.A condition that approaches the state of abundance and which will produce surpluses to be allocated to countries and territories that are struggling towards the condition of neutrality.The acceleration of lagging continents and the recovery of altered economic systems are therefore preconditions that can allow us to access the state of global neutrality.As we get closer to the great objective,it is to be believed that the pretense of regulating conflicts through war will also disappear.With the new reality of abundance,the economic reason for war disappears,while the aspiration of peoples-inscribed in their DNA-for solidarity and peaceful aggregation towards substantial unity becomes clear. 展开更多
关键词 monetary policy conjunctural cycles economic sustainability neutrality as goal continental aggregation
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