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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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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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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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Multi-objective optimization and evaluation of supercritical CO2 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 CO2 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 c... The supercritical CO2 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 CO2 Brayton cycle Nuclear power generation Thermo-economic analysis Multi-objective optimization Decision-making methods
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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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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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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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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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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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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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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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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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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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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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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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Effect of High Temperature Curing on the Frost Resistance of Recycled Aggregate Concrete and the Physical Properties of Second-Generation Recycled Coarse Aggregate under Freeze-Thaw Cycles 被引量:1
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作者 Xintong Chen Pinghua Zhu +2 位作者 Xiancui Yan Lei Yang Huayu Wang 《Journal of Renewable Materials》 SCIE EI 2023年第6期2953-2967,共15页
With the emphasis on environmental issues,the recycling of waste concrete,even recycled concrete,has become a hot spot in the field of architecture.But the repeated recycling of waste concrete used in harsh environmen... With the emphasis on environmental issues,the recycling of waste concrete,even recycled concrete,has become a hot spot in the field of architecture.But the repeated recycling of waste concrete used in harsh environments is still a complex problem.This paper discusses the durability and recyclability of recycled aggregate concrete(RAC)as a prefabricated material in the harsh environment,the effect of high-temperature curing(60℃,80℃,and 100℃)on the frost resistance of RAC and physical properties of the second generation recycled coarse aggregate(RCA_(2))of RAC after 300 freeze-thaw cycles were studied.The frost resistance of RAC was characterized by compressive strength,relative dynamic elastic modulus,and mass loss.As the physical properties of RCA_(2),the apparent density,water absorption,and crushing value were measured.And the SEM images of RAC after 300 freeze-thaw cycles were shown.The results indicated that the frost resistance of RAC cured at 80℃ for 7 days was comparable to that cured in the standard condition(cured for 28 days at 20℃±2℃ and 95%humidity),and the RAC cured at 100℃ was slightly worse.However,the frost resistance of RAC cured at 60℃ deteriorated seriously.The RAC cured at 80℃ for 7 days is the best.Whether after the freeze-thaw cycle or not,the RCA that curd at 60℃,80℃,and 100℃ for 7 days can also meet the requirements of Grade III RCA and be used as the aggregate of non-bearing part of prefabricated concrete components.RCA_(2) which is cured at 80℃ for 7 days had the best physical properties. 展开更多
关键词 Freeze-thaw cycles curing condition recycled aggregate concrete second-generation recycled coarse aggregate
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Life Cycle Assessment Introduced by Using Nanorefrigerant of Organic Rankine Cycle System for Waste Heat Recovery
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作者 Yuchen Yang Lin Ma +2 位作者 Jie Yu Zewen Zhao Pengfei You 《Journal of Renewable Materials》 SCIE EI 2023年第3期1153-1179,共27页
The use of nanorefrigerants in Organic Rankine Cycle(ORC)units is believed to affect the cycle environment performance,but backed with very few relevant studies.For this purpose,a life cycle assessment(LCA)has been pe... The use of nanorefrigerants in Organic Rankine Cycle(ORC)units is believed to affect the cycle environment performance,but backed with very few relevant studies.For this purpose,a life cycle assessment(LCA)has been performed for the ORC system using nanorefrigerant,the material and energy input,characteristic indicators and comprehensive index of environmental impact,total energy consumption and energy payback time(BPBT)of the whole life cycle of ORC system using Al_(2)O_(3)/R141b nanorefrigerant were calculated.Total environmental comprehensive indexes reveal that ECER-135 index decrease by 1.5%after adding 0.2%Al_(2)O_(3)nanoparticles to R141b.Based on the contribution analysis and sensitivity analysis,it can be found out ORC system manufacturing is of the most critical stage,where,the ECER-135 index of ORC component production is the greatest,followed by the preparation process of R141b,transportation phase,and that of Al_(2)O_(3)nanoparticles preparation is small.The retirement phase which has good environmental benefits affects the result significantly by recycling important materials.Meanwhile,the main cause and relevant suggestion for improvement were traced respectively.Finally,the environmental impacts of various power generations were compared,and results show that the power route is of obvious advantage.Among the renewable energy,ORC system using Al_(2)O_(3)/R141b nanorefrigerant with minimal environmental impact is only 0.67%of coal-fired power generation.The environmental impact of current work is about 14.34%of other nations’PV results. 展开更多
关键词 Life cycle assessment Organic Rankine cycle NANOREFRIGERANT total energy consumption energy payback time
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CO2 Air-Water Exchanges during Seasonal and Glacial Cycles
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作者 Arnaud Muller-Feuga 《Journal of Agricultural Chemistry and Environment》 2023年第4期365-385,共21页
Based on the photosynthesis-respiration reversible reaction and the available statistics, we attempted to quantify the planetary seasonal exchanges of CO<sub>2</sub> between air and water from 1970 and com... Based on the photosynthesis-respiration reversible reaction and the available statistics, we attempted to quantify the planetary seasonal exchanges of CO<sub>2</sub> between air and water from 1970 and compared them to the glacial ACC cycles as reported from ice cores archives. In 2020, the overall continental absorption (AW) was 8.0 giga tonnes of carbon per year (GtC/y). Emissions into the atmosphere (EW) resulting from mineral degradation by respiration and combustion of biomass and fossil hydrocarbons were 14.7 GtC/y, an increase of 2.4% per year since 1970. The continental surplus balance (-AW+EW) of 6.7 GtC/y was shared between the atmosphere, which received 5.1 GtC/y (GATM), and the ocean which absorbed 1.6 GtC/y. This ocean contribution (OC) corresponded to 17% of the 9.2 GtC/y emissions by combustion of fossil hydrocarbons (EFOS). Analysis of the ACC oscillations during 2020 in the northern hemisphere showed that the ocean absorbed 11.1 GtC during the warm season and outgassed 9.5 GtC during the cold season. Assuming proportionality to world population, the ACC, 414 parts per million (ppm) in 2021, would reach 584 ppm in 2080, still growing at a rate of 0.6% per year. The gain of atmospheric CO<sub>2</sub> (GATM) and its absorption by the ocean (OC) were expected to peak at 7.0 and 2.2 GtC/y, respectively, in 2080. This increase in the availability of atmospheric CO<sub>2</sub> resulted in improved yields of agriculture which more than compensated for the reduction by half of food-producing areas per capita from 1970. 展开更多
关键词 CO2 Budget Ocean Photosynthesis RESPIRATION Seasonal cycles Glacial cycles Agriculture Yields Food Availability
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CMT Cycle Step工艺参数对焊缝表面特征纹路及成形尺寸的影响
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作者 周春东 章晓勇 +3 位作者 彭勇 王克鸿 王剑春 周明 《焊接学报》 EI CAS CSCD 北大核心 2023年第5期95-101,I0008,I0009,共9页
采用CMT Cycle Step焊接工艺进行平板堆焊正交试验,研究了送丝速度、焊接速度、熔滴数量和间隔时间四个参数对焊缝表面特征纹路及成形尺寸的影响,建立了各参数与焊缝表面鱼鳞纹步长S、焊缝熔宽B、堆焊层厚度h之间的回归模型.结果表明,... 采用CMT Cycle Step焊接工艺进行平板堆焊正交试验,研究了送丝速度、焊接速度、熔滴数量和间隔时间四个参数对焊缝表面特征纹路及成形尺寸的影响,建立了各参数与焊缝表面鱼鳞纹步长S、焊缝熔宽B、堆焊层厚度h之间的回归模型.结果表明,随着焊接速度、熔滴数量和间隔时间的增大,焊缝表面鱼鳞纹步长S呈逐渐增大的趋势.适当减小焊接速度和间隔时间,可有效减小焊缝表面高度差Δh,提高焊缝表面成形质量.随着送丝速度和熔滴数量的增大,焊缝熔宽B和堆焊层厚度h均逐渐增大;随着焊接速度的增大,焊缝熔宽B和堆焊层厚度h逐渐减小.根据理论分析和回归分析得到准确性较高的回归方程,为预测焊接焊缝成形以及优化焊接工艺参数提供理论依据.创新点:(1)系统研究了CMT Cycle Step焊接工艺参数对焊缝成形的影响规律,有助于采用该方法解决点焊、热敏感材料焊接、电弧增材制造等领域的相关技术难题.(2)建立了CMT Cycle Step焊接工艺的送丝速度、焊接速度、熔滴数量和间隔时间四个参数对焊缝表面特征纹路及成形尺寸回归模型,为预测焊缝成形以及优化焊接工艺参数提供理论依据.(3)对CMT Cycle Step焊缝表面特征纹路—鱼鳞纹进行量化评价,探究工艺参数对焊缝表面鱼鳞纹步长S和表面高度差Δh的影响规律,有利于获得高表面平整度的焊缝. 展开更多
关键词 CMT cycle Step 焊缝表面特征纹路 正交试验 焊缝成形
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Cdk5 and aberrant cell cycle activation at the core of neurodegeneration 被引量:2
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作者 Raquel Requejo-Aguilar 《Neural Regeneration Research》 SCIE CAS CSCD 2023年第6期1186-1190,共5页
Neurodegenerative diseases are caused by the progressive loss of specific neurons.The exact mechanisms of action of these diseases are unknown,and many studies have focused on pathways related to abnormal accumulation... Neurodegenerative diseases are caused by the progressive loss of specific neurons.The exact mechanisms of action of these diseases are unknown,and many studies have focused on pathways related to abnormal accumulation and processing of proteins,mitochondrial dysfunction,and oxidative stress leading to apoptotic death.However,a growing body of evidence indicates that aberrant cell cycle re-entry plays a major role in the pathogenesis of neurodegeneration.The activation of the cell cycle in mature neurons could be promoted by several signaling mechanisms,including c-Jun N-terminal kinases,p38 mitogen-activated protein kinases,and mitogen-activated protein kinase/extracellular signal-regulated kinase cascades;post-translational modifications such as Tau-phosphorylation;and DNA damage response.In all these events,implicated Cdk5,a proline-directed serine/threonine protein kinase,seems to be responsible for several cellular processes in neurons including axon growth,neurotransmission,synaptic plasticity,neuronal migration,and maintenance of neuronal survival.However,under pathological conditions,Cdk5 dysregulation may lead to cell cycle re-entry in post-mitotic neurons.Thus,Cdk5 hyperactivation,by its physiologic activator p25,hyper-phosphorylates downstream substrates related to neurodegenerative diseases.This review summarizes factors such as oxidative stress,DNA damage response,signaling pathway disturbance,and Ubiquitin proteasome malfunction contributing to cell cycle re-entry in post-mitotic neurons.It also describes how all these factors are linked to a greater or lesser extent with Cdk5.Thus,it offers a global vision of the function of cell cycle-related proteins in mature neurons with a focus on Cdk5 and how this protein contributes to the development of Alzheimer’s disease,Parkinson’s disease,amyotrophic lateral sclerosis,and Huntington’s disease by cell cycle activation. 展开更多
关键词 Alzheimer´s disease amyotrophic lateral sclerosis apoptosis CDK5 cell cycle Huntington´s disease NEURODEGENERATION neuron oxidative stress Parkinson´s disease signaling Tau phosphorylation
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