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Predictable and Unpredictable Modes of Northern Hemisphere Atmospheric Circulation in CMIP6:Evaluation and Projections
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作者 Kairan YING Dabang JIANG Linhao ZHONG 《Advances in Atmospheric Sciences》 2026年第1期135-156,共22页
Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both g... Climate models are essential for understanding past,present,and future changes in atmospheric circulation,with circulation modes providing key sources of seasonal predictability and prediction uncertainties for both global and regional climates.This study assesses the performance of models participating in phase 6 of the Coupled Model Intercomparison Project in simulating interannual variability modes of Northern Hemisphere 500-hPa geopotential height during winter and summer,distinguishing predictable(potentially predictable on seasonal or longer timescales)and unpredictable(intraseasonal and essentially unpredictable at long range)components,using reanalysis data and a variance decomposition method.Although most models effectively capture unpredictable modes in reanalysis,their ability to reproduce dominant predictable modes-specifically the Pacific-North American pattern,Arctic Oscillation,and Western Pacific Oscillation in winter,and the East Atlantic and North Atlantic Oscillations in summer-varies notably.An optimal ensemble is identified to distinguish(a)predictable-external modes,dominated by external forcing,and(b)predictable-internal modes,associated with slow internal variability,during the historical period(1950-2014)and the SSP5-8.5 scenario(2036-2100).Under increased radiative forcing,the leading winter/summer predictable-external mode exhibits a more uniform spatial distribution,remarkably larger trend and annual variance,and enhanced height-sea surface temperature(SST)covariance under SSP5-8.5 compared to historical conditions.The dominant winter/summer predictable-internal modes also exhibit increased variance and height-SST covariance under SSP5-8.5,along with localized changes in spatial configuration.Minimal changes are observed in spatial distribution or variance for dominant winter/summer unpredictable modes under SSP5-8.5.This study,from a predictive perspective,deepens our understanding of model uncertainties and projected changes in circulations. 展开更多
关键词 interannual mode of atmospheric circulation CMIP6 predictable unpredictable EVALUATION PROJECTION
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Two Unconventional Types of Large-scale Circulation Anomalies Inducing Heavy Rainfall over the Yangtze River Basin
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作者 Xinyu LI Mengyao CHEN Riyu LU 《Advances in Atmospheric Sciences》 2026年第3期565-577,共13页
Summer rainfall in the Yangtze River basin(YRB)is favored by two key factors in the lower troposphere:the tropical anticyclonic anomaly over the western North Pacific and the extratropical northeasterly anomalies to t... Summer rainfall in the Yangtze River basin(YRB)is favored by two key factors in the lower troposphere:the tropical anticyclonic anomaly over the western North Pacific and the extratropical northeasterly anomalies to the north of the YRB.This study,however,found that approximately 46%of heavy rainfall events in the YRB occur when only one factor appears and the other is opposite signed.Accordingly,these heavy rainfall events can be categorized into two types:the extratropical northeasterly anomalies but tropical cyclonic anomaly(first unconventional type),and the tropical anticyclonic anomaly but extratropical southwesterly anomalies(second unconventional type).Anomalous water vapor convergence and upward motion exists for both types,but through different mechanisms.For the first type,the moisture convergence and upward motion are induced by a cyclonic anomaly over the YRB,which appears in the mid and lower troposphere and originates from the upstream region.For the second type,a mid-tropospheric cyclonic anomaly over Lake Baikal extends southward and results in southwesterly anomalies over the YRB,in conjunction with the tropical anticyclonic anomaly.The southwesterly anomalies transport water vapor to the YRB and lead to upward motion through warm advection.This study emphasizes the role of mid-tropospheric circulations in inducing heavy rainfall in the YRB. 展开更多
关键词 Yangtze River basin heavy rainfall large-scale circulation anomalies
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Wind-induced circulation driving the spatial distribution of dominant algae population in a plateau lake,Erhai,China
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作者 Jing Cao Yue Wu +4 位作者 Zeying Hou Kunlin Yang Zhaosheng Chu Zhiwei Gao Hao Yang 《Journal of Environmental Sciences》 2026年第1期741-755,共15页
Wind-induced circulation is the main form of lake flow for shallow lakes and plays an important role in algae population distribution.This study constructed a three-dimensional hydrodynamic model(EFDC)of the plateau l... Wind-induced circulation is the main form of lake flow for shallow lakes and plays an important role in algae population distribution.This study constructed a three-dimensional hydrodynamic model(EFDC)of the plateau lake Erhai,China using accuracy wind field observation,runoff data and monthly algae data during 2022–2023.The model successfully reproduced the circulation characteristics of Erhai under prevailing wind directions.The results showed that the lake flow velocity in Lake Erhai is higher in winter than in summer,with lower velocities near shore particularly in the northern and central parts of the lake.There is a negative correlation between algal biomass and flow velocity(FV)in different zones,with lower FV favoring the accumulation of algal biomass,particularly for Microcystis,Dolichospermum,and Peridinium.Additionally,due to buoyancy,cyanobacteria are highly affected by wind direction and tend to accumulate in downwind regions of the prevailing wind direction.This study demonstrates that wind-induced circulation is a crucial factor affecting the spatial distribution of dominant algae populations in shallow plateau lakes with weak hydrodynamic force.Further,the risk of bloom occurrence in Lake Erhai will be higher due to the background of global climate change and the lake’s wind speed decline.In conclusion,we suggest implementing targeted zoning measures to control algal blooms and establishing stricter regulations for nitrogen and phosphorus control to counterbalance the promotion of algal bloom accumulation in low-velocity zones caused by reduced wind speed. 展开更多
关键词 Wind-induced circulation Dominant algae populations Three-dimensional hydrodynamic model MICROCYSTIS Peridinium
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Impact of refined oceanic model resolution on the simulation of Atlantic meridional overturning circulation in LICOM3
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作者 Xiaowei Wang Yongqiang Yu +1 位作者 Zipeng Yu Pengfei Lin 《Atmospheric and Oceanic Science Letters》 2026年第2期42-47,共6页
The present study compares the Atlantic Meridional Overturning Circulation(AMOC)in the North Atlantic from two simulations by an oceanic general circulation model with 1°×1°and 0.1°×0.1°r... The present study compares the Atlantic Meridional Overturning Circulation(AMOC)in the North Atlantic from two simulations by an oceanic general circulation model with 1°×1°and 0.1°×0.1°resolution,respectively,which explores the sensitivity of AMOC to the resolution.The ocean model is the latest version of the LASG/IAP Climate System Model(LICOM3),and it is forced with atmospheric data from phase 2 of the Ocean Model Intercomparison Project(OMIP2).Comprehensive comparison between the two simulations indicates that the simulated AMOC is highly sensitive to the spatial resolution.The high-resolution model(LICOM-H)simulates a deeper mixed-layer depth(MLD),due to increased surface salinity,than that in the low-resolution model(LICOML)in the Labrador Sea,and it also has stronger AMOC strength(the maximum climatic mean AMOC from 1958 to 2018 is 23.4 Sv for LICOM-H and 21.2 Sv for LICOM-L)and larger variability of AMOC index(2.3 Sv for LICOM-H and 1.7 Sv for LICOM-L).These differences can mainly be attributed to two main dynamic processes that benefit from high resolution.Firstly,LICOM-H can simulate much stronger boundary currents(~0.6 m s^(-1))than LICOM-L(0.3 m s^(-1))in the upper ocean,which leads to saltier and warmer seawater being transported to the Labrador Sea,where it enhances deep convection.Secondly,in LICOM-H,the stronger variability of AMOC is related to the higher sensitivity of the MLD and transformation to the prescribed atmospheric forcing in the Labrador Sea. 展开更多
关键词 Atlantic meridional overturning circulation Eddy-resolving ocean model North Atlantic TRANSFORMATION
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Improvement of Low-cloud Simulations with a Revised Cloud Microphysics Scheme in an Atmospheric General Circulation Model
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作者 LI Jia-bo PENG Xin-dong +2 位作者 LI Xiao-han GU Juan DUAN Sheng-ni 《Journal of Tropical Meteorology》 2026年第1期1-18,共18页
Clouds play an important role in global atmospheric energy and water vapor budgets, and the low cloud simulations suffer from large biases in many atmospheric general circulation models. In this study, cloud microphys... Clouds play an important role in global atmospheric energy and water vapor budgets, and the low cloud simulations suffer from large biases in many atmospheric general circulation models. In this study, cloud microphysical processes such as raindrop evaporation and cloud water accretion in a double-moment six-class cloud microphysics scheme were revised to enhance the simulation of low clouds using the Global-Regional Integrated Forecast System(GRIST)model. The validation of the revised scheme using a single-column version of the GRIST demonstrated a reasonable reduction in liquid water biases. The revised parameterization simulated medium-and low-level cloud fractions that were in better agreement with the observations than the original scheme. Long-term global simulations indicate the mitigation of the originally overestimated low-level cloud fraction and cloud-water mixing ratio in mid-to high-latitude regions,primarily owing to enhanced accretion processes and weakened raindrop evaporation. The reduced low clouds with the revised scheme showed better consistency with satellite observations, particularly at mid-and high-latitudes. Further improvements can be observed in the simulated cloud shortwave radiative forcing and vertical distribution of total cloud cover. Annual precipitation in mid-latitude regions has also improved, particularly over the oceans, with significantly increased large-scale and decreased convective precipitation. 展开更多
关键词 low cloud cloud microphysics scheme general circulation model accretion process raindrop evaporation
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Effect of SO_(2)circulation on pellet quality in grate-kiln process
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作者 Qiu-Yu Li Zi-Jian Su +4 位作者 Ke Ma Yuan-Bo Zhang Xiao-Guang Bai Guo-Wei Fu Tao Jiang 《Journal of Iron and Steel Research International》 2026年第3期1-15,共15页
High-sulfur iron concentrates emit SO_(2)into the flue gas during pellet induration.To investigate the effect of the SO_(2)cycle on pellet quality in the grate-kiln process,sulfur balance analysis,thermodynamic calcul... High-sulfur iron concentrates emit SO_(2)into the flue gas during pellet induration.To investigate the effect of the SO_(2)cycle on pellet quality in the grate-kiln process,sulfur balance analysis,thermodynamic calculations,and pellet production experiments under simulated flue gas circulation conditions were conducted.The results indicated that SO_(2)circulation inhibited desulfurization and deteriorated pellet strength.SO_(2)absorption increased the pellet sulfur content to 0.70 wt.%during the downdraft drying phase,and the absorption could be aggravated by the moisture.The desulfurization rate of the preheating process was also decreased to 16.67%,resulting from the refractory sulfate generation.Sulfur content of the roasted pellets dropped to 0.13 wt.%because of the aluminosilicate generation.The finished pellet sulfur content further decreased to 0.08 wt.%due to the fresh air during the cooling process.Eventually,optimization measures were proposed when high-sulfur iron concentrates were used for oxidized pellet preparation. 展开更多
关键词 SO_(2)circulation SO_(2)absorption Refractory sulfate Pellet preparation Production optimization
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Co-circulation of H3N2 canine influenza and distemper viruses in canine populations from Liaoning,China
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作者 Siqi Tang Yaoqi Wang +4 位作者 Xiaorui Zhang Hailing Li Haoyu Leng Yali Feng Ying Zhang 《Journal of Integrative Agriculture》 2026年第2期824-827,共4页
Influenza A virus(IAV) has a wide host range,including wild birds,poultry,various mammals,and even humans(Xu et al.2024).Currently,two subtypes of canine influenza virus(CIV),H3N8 and H3N2,are primarily circulating in... Influenza A virus(IAV) has a wide host range,including wild birds,poultry,various mammals,and even humans(Xu et al.2024).Currently,two subtypes of canine influenza virus(CIV),H3N8 and H3N2,are primarily circulating in dogs.The H3N8 CIV was introduced from horses into dogs in 2004(Crawford et al.2005),while the H3N2 CIV originated from chickens in Asia in 2007(Song et al.2008).In China,H3N2 is the predominant CIV subtype,with a prevalence rate of up to 5.63% in the canine population,as reported by Chen et al.(2023).CIV infection typically manifests with symptoms such as coughing,sneezing,runny nose,and fever but is rarely fatal.However,co-infection with other pathogens(e.g.,Streptococcus,Mycoplasma or canine parainfluenza virus) can exacerbate symptoms and lead to lethal outcomes(Yondo et al.2023). 展开更多
关键词 influenza virus iav canine influenza virus distemper virus co infection China co circulation h n canine influenza virus civ h n
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THE DOUBLE-LAYER STRUCTURE OF THE HADLEY CIRCULATION AND ITS INTERDECADAL EVOLUTION CHARACTERISTICS 被引量:1
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作者 CHENG Jian-bo HU Shu-juan CHOU Ji-fan 《Journal of Tropical Meteorology》 SCIE 2018年第2期220-231,共12页
Based on the three-pattern decomposition of global atmospheric circulation(TPDGAC), this study investigates the double-layer structure of the Hadley circulation(HC) and its interdecadal evolution characteristics by us... Based on the three-pattern decomposition of global atmospheric circulation(TPDGAC), this study investigates the double-layer structure of the Hadley circulation(HC) and its interdecadal evolution characteristics by using monthly horizontal wind field from NCEP/NCAR reanalysis data from 1948—2011. The following major conclusions are drawn: First, the double-layer structure of the HC is an objective fact, and it constantly exists in April,May, June, October and November in the Southern Hemisphere. Second, the double-layer structure is more obvious in the Southern than in the Northern Hemisphere. Since the double-layer structure is sloped in the vertical direction, it should be taken into consideration when analyzing the variations of the strength and location of the center of the HC.Third, the strength of the double-layer structure of the HC in the Southern Hemisphere consistently exhibits decadal variations with a strong, weak and strong pattern in all five months(April, May, June, October, and November), with cycles of 20-30 a and 40-60 a. Fourth, the center of the HC(mean position of the double-layer structure) in the Southern Hemisphere consistently and remarkably shifts southward in all the five months. The net poleward shifts over the 64 years are 5.18°, 2.11°, 2.50°, 1.79° and 5.76° for the five respective months, with a mean shift of 3.47°. 展开更多
关键词 three-pattern decomposition of global atmospheric circulation Hadley circulation double-layer structure decadal variations
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Plugging mode of flaky lost circulation materials within fractures and mechanism to enhance pressure-bearing capacity for the plugging zone 被引量:1
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作者 Kun Guo Yi-Li Kang +3 位作者 Cheng-Yuan Xu Chong Lin Ling-Jie Zhang Li-Jun You 《Petroleum Science》 2025年第8期3315-3332,共18页
During drilling operations in deep fractured tight gas reservoirs,lost circulation of working fluid frequently occurs due to the formationʼs low pressure-bearing capacity.Adding lost circulation materials(LCMs)to dril... During drilling operations in deep fractured tight gas reservoirs,lost circulation of working fluid frequently occurs due to the formationʼs low pressure-bearing capacity.Adding lost circulation materials(LCMs)to drilling fluids is the most common method for controlling lost circulation.Among these,granular LCMs are widely used,but the application frequency of flaky LCMs has been increasing annually due to their unique morphology.However,the migration and plugging behavior of flaky LCMs within fractures,and the mechanisms enhancing the pressure-bearing capacity of the plugging zone are not well understood.Therefore,this study conducted visual plugging experiments and dynamic fracture plugging experiments to evaluate the plugging mode and pressure-bearing capacity of the plugging slurry with various particle sizes and concentrations of flaky LCMs.The experimental results demonstrate that the fracture plugging process can be divided into four stages:uniform flow stage of the plugging slurry,formation and development stage of the bridging area,formation and development stage of the plugging area,and pressure-bearing stage of the plugging zone.The inclusion of flaky LCMs notably reduces the duration of stages 1 and 2,while simultaneously increasing the proportion of the plugging zone and enhancing its surface porosity.Flaky LCMs reduce the effective fracture width through“interception”and“co-bridging”modes,thus improving plugging zone formation efficiency.Appropriate particle size and concentration of flaky LCMs increase the area and length of the plugging zone.This reduces the fracture width increment caused by injection pressure and enhances frictional force between the plugging zone and fracture surface,thereby improving the pressure-bearing capacity of the plugging zone.However,excessively high concentrations of flaky LCMs result in decreased structural stability of the plugging zone,and excessively large particle sizes increase the risk of plugging outside fracture inlet.The recommended concentration of flaky LCMs in the plugging slurry is 2%–3%,with a particle size 1.2 to 1.5 times that of the bridging granular LCMs and not exceeding twice the fracture width.This study provides a theoretical foundation for selecting LCMs and designing plugging formulations for field applications. 展开更多
关键词 Lost circulation Flaky lost circulation materials Fracture plugging zone Visualization Pressure-bearing capacity
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A multisource geomagnetic field model incorporating ocean circulation-induced magnetic field 被引量:5
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作者 HongBo Yao JuYuan Xu +2 位作者 Cong Yang ZhengYong Ren Keke Zhang 《Earth and Planetary Physics》 2025年第3期550-563,共14页
The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic... The movement of global ocean circulation in the Earth’s main magnetic field generates a measurable induced magnetic field(about 2 nT at geomagnetic satellite altitudes).However,this ocean circulation-induced magnetic field has not been previously estimated or incorporated into geomagnetic field models,potentially causing leakage into the core field model.Here,we present a method to account for the circulation-induced magnetic field during geomagnetic field modeling.First,a forward model of the circulation-induced magnetic field is constructed by numerically solving electromagnetic induction equations based on a realistic ocean circulation model.Then,this forward model is subtracted from the observed data.Finally,the core and lithospheric fields,magnetospheric and Earth’s mantle-induced fields,and the ocean tide-induced magnetic field are co-estimated.Applying our method to over 20 years of MSS-1,Swarm,CryoSat-2,and CHAMP satellite magnetic data,we derive a new multisource geomagnetic field model(MGFM).We find that incorporating a forward model of the circulation-induced magnetic field marginally improves the fit to the data.Furthermore,we demonstrate that neglecting the circulation-induced magnetic field in geomagnetic field modeling results in leakage into the core field model.The highlights of the MGFM model include:(i)a good agreement with the widely used CHAOS model series;(ii)the incorporation of magnetic fields induced by both ocean tides and circulation;and(iii)the suppression of leakage of the circulation-induced magnetic field into the core field model. 展开更多
关键词 Macao Science Satellite-1(MSS-1) geomagnetic field modeling ocean tides ocean circulation
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Evaluation of the Effectiveness and Improvement of Quality of Life of Tianma Gouteng Decoction Combined with Betahistine Mesylate in Treating Posterior Circulation Ischemic Vertigo 被引量:1
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作者 Jing Ding Yusheng Zhang 《Journal of Clinical and Nursing Research》 2025年第6期325-332,共8页
Objective:To evaluate the therapeutic effect of Tianma Gouteng Decoction combined with Betahistine Mesylate in patients with posterior circulation ischemic vertigo(PCI).Methods:Eighty-two patients with PCI who visited... Objective:To evaluate the therapeutic effect of Tianma Gouteng Decoction combined with Betahistine Mesylate in patients with posterior circulation ischemic vertigo(PCI).Methods:Eighty-two patients with PCI who visited the hospital from February 2024 to February 2025 were selected as samples and randomly divided into two groups.Group A received Tianma Gouteng Decoction combined with Betahistine Mesylate,while Group B received only Betahistine Mesylate.The efficacy,syndrome scores,hemodynamics,and quality of life indicators were compared between the two groups.Results:The efficacy of PCI treatment in Group A was higher than that in Group B(P<0.05).The syndrome scores in Group A were lower than those in Group B(P<0.05).The peak systolic velocity(PSV)of the basilar artery and left and right vertebral arteries in Group A were higher than those in Group B(P<0.05).The quality of life(SF-36)score in Group A was higher than that in Group B(P<0.05).Conclusion:Tianma Gouteng Decoction combined with Betahistine Mesylate is effective and feasible in the treatment of PCI,with improved hemodynamic indicators and reduced disease scores. 展开更多
关键词 Posterior circulation ischemic vertigo Betahistine mesylate Tianma Gouteng Decoction EFFICACY
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Prediction of lost circulation risk in fractured formations based on 3D geomechanical modeling 被引量:1
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作者 Jinfa Zhang Yongcun Feng +4 位作者 Sijia Ma Zhijuan Hao Bing He Jingyi Wei Jingen Deng 《International Journal of Mining Science and Technology》 2025年第11期1955-1973,共19页
Due to complex geological structures and a narrow safe mud density window,offshore fractured formations frequently encounter severe lost circulation(LC)during drilling,significantly hindering oil and gas exploration a... Due to complex geological structures and a narrow safe mud density window,offshore fractured formations frequently encounter severe lost circulation(LC)during drilling,significantly hindering oil and gas exploration and development.Predicting LC risks enables the targeted implementation of mitigation strategies,thereby reducing the frequency of such incidents.To address the limitations of existing 3D geomechanical modeling in predicting LC,such as arbitrary factor selection,subjective weight assignment,and the inability to achieve pre-drilling prediction along the entire well section,an improved prediction method is proposed.This method integrates multi-source data and incorporates three LC-related sensitivity factors:fracture characteristics,rock brittleness,and in-situ stress conditions.A quantitative risk assessment model for LC is developed by combining the subjective analytic hierarchy process with the objective entropy weight method(EWM)to assign weights.Subsequently,3D geomechanical modeling is applied to identify regional risk zones,enabling digital visualization for pre-drilling risk prediction.The developed 3D LC risk prediction model was validated using actual LC incidents from drilled wells.Results were generally consistent with field-identified LC zones,with an average relative error of 19.08%,confirming its reliability.This method provides practical guidance for mitigating potential LC risks and optimizing drilling program designs in fractured formations. 展开更多
关键词 Fractured formations Lost circulation risk Geomechanical modeling Geological-engineering integration Analytic hierarchy process Entropy weight method
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Application of promoting blood circulation and resolving blood stasis in intracerebral hemorrhage:a traditional method gradually being reconsidered 被引量:1
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作者 ZHANG Dingshan CHEN Li +3 位作者 MARYAM Mazhar XUE Jinyi LIU Ping LIU Mengnan 《Journal of Traditional Chinese Medicine》 2025年第2期458-472,共15页
Intracerebral hemorrhage(ICH) is a significant and growing threat to human health,with increasing incidence.Promoting blood circulation and removing blood stasis therapy(PBCRBS),a Traditional Chinese Medicine therapy,... Intracerebral hemorrhage(ICH) is a significant and growing threat to human health,with increasing incidence.Promoting blood circulation and removing blood stasis therapy(PBCRBS),a Traditional Chinese Medicine therapy,can be an adjuvant therapy to benefit patients with ICH by improving clinical efficacy.However,in theory,using PBCRBS to treat ICH carries the risk of hematoma enlargement and rebleeding,which has led to controversy over its application in ICH treatment.To demonstrate the effectiveness and safety of PBCRBS in treating ICH,this review first analyzes the pathological and physiological basis of ICH and secondly,the cascade of response after ICH and the involvement of cytokines and signaling pathways in this process.Finally,experimental and clinical studies on the treatment of ICH with PBCRBS over the past decade were retrieved from the Pub Med and China National Knowledge Infrastructure databases,and the content of these studies was used to summarize commonly used herbs with PBCRBS effects and their mechanisms of action.Through analysis,hypertension has been identified as the most common cause of ICH.Heme,interleukin,reactive oxygen species,coagulation promoting particles and other induced mass effects,inflammation,oxidative stress,and coagulation cascade reactions lead to brain damage following ICH.This review includes 56 experimental studies and 83 clinical studies summarizing 28 commonly used herbs,demonstrating the positive impact of PBCRBS as an adjuvant therapy for ICH.In summary,PBCRBS appears effective and safe for treating ICH. 展开更多
关键词 cerebral hemorrhage ETIOLOGY PATHOLOGY PHYSIOPATHOLOGY medicine Chinese traditional promoting blood circulation and removing blood stasis review
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The strongest early-summer drought–flood abrupt alternation event over the Huang–Huai–Hai River Basin in 2024 since the 1980s:Perspective of anomalous subseasonal circulation evolution 被引量:1
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作者 Zhiheng Chen Zhihai Zheng 《Atmospheric and Oceanic Science Letters》 2025年第5期65-72,共8页
Since the 21st century,the Huang–Huai–Hai River Basin(HHHRB)in China has experienced increased frequency and severity of drought–flood abrupt alternation(DFAA)events during early summer,characterized by droughts in... Since the 21st century,the Huang–Huai–Hai River Basin(HHHRB)in China has experienced increased frequency and severity of drought–flood abrupt alternation(DFAA)events during early summer,characterized by droughts in June followed by floods in July.The 2024 event was the most severe since 1981.This study demonstrates that such compound extreme events are closely linked to anomalous subseasonal evolution of large-scale atmospheric circulation.During the drought phase,the East Asian subtropical westerly jet(EAJ)shifts southward,and the western Pacific subtropical high(WPSH)exhibits anomalous strengthening with its western ridge line displaced southward.The flood phase is characterized by acceleration of the EAJ,westward extension of the WPSH,and enhanced southwestern moisture transport from the western Pacific.Beyond these typical features,the 2024 early summer circulation exhibited unique characteristics:Anomalous northeastward intensification of the WPSH facilitated merged moisture influx from both the Indian Ocean and the western Pacific along the southeast pathway into the HHHRB in July,resulting in the highest net moisture inflow at the southern boundary of the HHHRB since 1981.The synergistic effects of multiple factors primarily explain the exceptionally intense DFAA event in 2024. 展开更多
关键词 Drought-flood abrupt alternation Anomalous subseasonal circulation evolution East Asian subtropical westerly jet Western Pacific subtropical high Water vapor transportation
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Preparation and performance of high temperature resistant and high strength self-healing lost circulation material in the drilling industry
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作者 Dan Bao Si-Yuan Liu +6 位作者 Yan-Jie Yang Yu-Tong Sang Zhi-Peng Miao Hua Li Biao Wang Tao-Song Liang Peng Zhang 《Petroleum Science》 2025年第9期3655-3670,共16页
Lost circulation of drilling fluid is an international engineering problem during drilling.Aiming at the problems of the first-time lost circulation control success rate and poor adaptability of traditional lost circu... Lost circulation of drilling fluid is an international engineering problem during drilling.Aiming at the problems of the first-time lost circulation control success rate and poor adaptability of traditional lost circulation materials,a new self-healing lost circulation material based on dynamic disulfide bonds was prepared and named CKSH.In this paper,the particle size of self-healing lost circulation material was from 0.1 to 5 mm.The structure was analyzed by modern characterization means,and the drilling fluid compatibility,self-healing performance were evaluated.The self-healing and bridging-filling-sealing mechanism of CKSH were revealed.The results showed that the healing rate of CKSH could reach100%after 12 h over 70℃.It showed good compatibility with drilling fluid,with no effect on rheology or filtration loss.It could be stably suspended in drilling fluid,and the temperature resistance reached140℃.Healing by self-healing lost circulation materials of different particle size,the pressure bearing capacity of plugging zone were over 12 MPa for fracture opening of 1–5 mm.It could play a synergistic role with traditional lost circulation materials by chemical bonding,and the repeated loss caused by physical plugging was avoided.The research results of this paper can improve the bridging plugging bearing pressure strength and the first-time lost circulation control success rate,which is of great significance for improving drilling efficiency and reducing non-productive time. 展开更多
关键词 Drilling fluid Lost circulation Plugging Self-healing lost circulation material Dynamic disulfide bonds
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Superconductivity and band topology of double-layer honeycomb structure M_(2)N_(2)(M=Nb,Ta)
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作者 Jin-Han Tan Na Jiao +2 位作者 Meng-Meng Zheng Ping Zhang Hong-Yan Lu 《Chinese Physics B》 2025年第9期581-587,共7页
Two-dimensional double-layer honeycomb(DLHC)materials are known for their diverse physical properties,but superconductivity has been a notably absent characteristic in this structure.We address this gap by investigati... Two-dimensional double-layer honeycomb(DLHC)materials are known for their diverse physical properties,but superconductivity has been a notably absent characteristic in this structure.We address this gap by investigating M_(2)N_(2)(M=Nb,Ta)with DLHC structure using first-principles calculations.Our results show that M_(2)N_(2)are stable and metallic,exhibiting superconducting behavior.Specifically,Nb_(2)N_(2)and Ta_(2)N_(2)display superconducting transition temperatures of 6.8 K and 8.8 K,respectively.Their electron-phonon coupling is predominantly driven by the coupling between metal d-orbitals and low-frequency metal-dominated vibration modes.Interestingly,two compounds also exhibit non-trivial band topology.Thus,M_(2)N_(2)are promising platforms for studying the interplay between topology and superconductivity and fill the gap in superconductivity research for DLHC materials. 展开更多
关键词 first-principles calculations phonon-mediated superconductivity double-layer honeycomb structure band topology
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Evolution and Innovation of Agricultural Production Organization Governance Mechanism under Large-scale Farmland Circulation:A Study Based on 175 Questionnaire Survey in Daqing City
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作者 Shuli SONG Ming LIU +1 位作者 Mingyang XIE Min TANG 《Asian Agricultural Research》 2025年第10期5-7,13,共4页
Based on questionnaire surveys and field interviews conducted with various types of agricultural production organizations across five districts and four counties in Daqing City,this study combines relevant theoretical... Based on questionnaire surveys and field interviews conducted with various types of agricultural production organizations across five districts and four counties in Daqing City,this study combines relevant theoretical frameworks to systematically examine the evolution,performance,and influencing factors of governance mechanisms within these organizations.Using both quantitative and inductive analytical methods,the paper proposes innovative designs and supporting measures for improving governance mechanisms.The findings reveal that,amid large-scale farmland circulation,the governance mechanisms of agricultural production organizations in Daqing City are evolving from traditional to modern structures.However,challenges remain in areas such as decision-making efficiency,benefit distribution,and supervision mechanisms.In response,this study proposes innovative governance designs focusing on decision-making processes,profit-sharing mechanisms,and risk prevention.Corresponding policy recommendations are also provided to support the sustainable development of agricultural modernization in China. 展开更多
关键词 LARGE-SCALE circulation AGRICULTURAL production ORGANIZATION GOVERNANCE mechanism
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Development of an atherosclerosis rabbit model to evaluate the hemodynamic impact of extracorporeal circulation
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作者 Anna Kathrin Assmann Jan Buschmann +5 位作者 Sinje Reimers Aleyna Karakas Elvira Weber Hug Aubin Artur Lichtenberg Alexander Assmann 《Animal Models and Experimental Medicine》 2025年第3期523-533,共11页
Background:Aortic atherosclerosis increases the risk of embolic events under extracorporeal circulation(ECC).To evaluate the hemodynamic impact of ECC on atheromatous plaques,an atherosclerosis animal model,which is a... Background:Aortic atherosclerosis increases the risk of embolic events under extracorporeal circulation(ECC).To evaluate the hemodynamic impact of ECC on atheromatous plaques,an atherosclerosis animal model,which is also eligible for ECC,is required.Methods:Twenty-nine New Zealand White rabbits received a pro-atherosclerotic diet(group diet,n=10),a pro-atherosclerotic diet and additional intraaortic balloon insufflation injury(group BI,n=9),or served as controls(n=10).After 3 or 6 months,aortic explants were analyzed by(immuno-)histology and RT-PCR.Results:Blood serum analyses revealed increased cholesterol-levels in groups diet and BI compared to controls(3 months:p=0.03 each,6 months:p<0.0001 each).Aortic inflammatory infiltration was significantly enhanced in groups diet(CD3 at 3 months:p<0.0001,6 months:p=0.02;CD68 at 3 months:p=0.01)and BI(CD3 at 3 months:p<0.0001,6 months:p=0.03;CD68 at 3 months:p=0.04,6 months:p=0.02).Increased intima hyperplasia occurred in both groups(p<0.0001 each).Macroscopic analyses after 3 and 6 months showed ubiquitous lumen-narrowing aortic plaques.Calcification of the intima and media was increased in groups diet(intima:p<0.0001 at 3 and 6 months;media at 3 months:p<0.0001,6 months:p=0.01)and BI(intima:p<0.0001 at 3 and 6 months;media at 3 months:p<0.0001,6 months:p=0.02).Extensive lipid accumulation was found in the intima in both treatment groups(p<0.0001 each).Conclusions:A rabbit model with high aortic calcific plaque burden—diet-induced with no implicit need of an additional intimal injury by an intraaortic balloon insufflation due to comparable outcome—exhibiting multiple pathophysiological aspects of human atherosclerosis has been designed and thoroughly characterized.It is suitable for use in future studies on the interaction between atherosclerotic plaques and the arterial blood flow under ECC. 展开更多
关键词 animal model ATHEROSCLEROSIS CALCIFICATION extracorporeal circulation INFLAMMATION PLAQUES
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Co-circulation of all four DENV serotypes during 2016 outbreak in Sinaloa,Mexico:First report of DENV-4 in patients
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作者 Annete Itzel Apodaca-Medina JoséIsrael Torres-Avendaño +5 位作者 Hipólito Castillo-Ureta Edith Hilario Torres-Montoya Sergio Alonso Durán-Pérez Lorenzo Ulises Osuna-Martínez María Elena Báez-Flores José Guadalupe Rendón-Maldonado 《Virologica Sinica》 2025年第4期680-683,共4页
Dear Editor,Dengue virus(DENV)is a positive-sense single-stranded RNA virus belonging to the Flaviviridae family,which causes dengue—a disease affecting over 400 million people annually worldwide.DENV is transmitted ... Dear Editor,Dengue virus(DENV)is a positive-sense single-stranded RNA virus belonging to the Flaviviridae family,which causes dengue—a disease affecting over 400 million people annually worldwide.DENV is transmitted through the bite of mosquitoes from the Aedes genus,primarily Aedes aegypti,and has a wide distribution in tropical and subtropical areas(de Souza et al.,2022). 展开更多
关键词 OUTBREAK Co circulation DENV Sinaloa Mexico SEROTYPES Dengue virus
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Regional Perspective of Hadley Circulation and Its Uncertainties among Different Datasets:Biases of ENSO-Related Hadley Circulation in CMIP Models
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作者 Wenzhu WANG Juan FENG +2 位作者 Yadi LI Yujie MIAO Xichen LI 《Advances in Atmospheric Sciences》 2025年第10期2067-2082,共16页
The Hadley Circulation(HC),a fundamental component of global atmospheric circulation,plays an important role in the global energy balance and transport of moisture.The interaction between ENSO and the HC significantly... The Hadley Circulation(HC),a fundamental component of global atmospheric circulation,plays an important role in the global energy balance and transport of moisture.The interaction between ENSO and the HC significantly impacts tropical climate and has broad implications for global climate variability through atmospheric teleconnections.The HC is usually represented by the mass stream function.As a result,it can rarely be observed through in-situ measurement.Reanalysis datasets and CMIP models are frequently used to investigate the properties of the HC.Previous studies systematically assess the capability of these CMIP models to represent the spatial distribution and intensity of the HC anomalies associated with ENSO events.However,most of these studies investigate the HC anomaly from a global perspective.In this work,we focus on evaluating the ability of CMIP6 models to capture the three-dimensional features of ENSO-related HC anomalies in comparison to that in six reanalysis datasets.Results show a consistent westward shift of the ENSO-related HC over the tropical Central-Eastern Pacific in almost all CMIP6 models,accompanied by a weakening of the asymmetric component of the ENSO-related HC over the equatorial Pacific.The former is mainly attributed to the westward extension of the Pacific cold tongue in CMIP models,while the latter is more related to the southward shift of the ENSO-related SST and precipitation anomalies in CMIP models.One should be aware of these biases when studying the ENSO-related atmospheric circulation changes.Our study has broad implications for ENSO simulations and the predictability of ENSO-related global climate variabilities. 展开更多
关键词 regional Hadley circulation ENSO CMIP6 atmosphere-ocean interaction
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