Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’...Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease.展开更多
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
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
This study investigates the relationship between atmospheric stratification (i.e., static stability given by N^(2)) and the vertical energy transfer of stationary planetary waves, and further illustrates the underlyin...This study investigates the relationship between atmospheric stratification (i.e., static stability given by N^(2)) and the vertical energy transfer of stationary planetary waves, and further illustrates the underlying physical mechanism. Specifically, for the simplified case of constant stratospheric N^(2), the refractive index square of planetary waves has a theoretical tendency to increase first and then decrease with an increased N^(2), whereas the group velocity weakens. Mechanistically, this behavior can be understood as an intensified suppression of vertical isentropic surface displacement caused by meridional heat transport of planetary waves under strong N^(2) conditions. Observational analysis corroborates this finding, demonstrating a reduction in the vertical-propagation velocity of waves with increased N^(2). A linear, quasi- geostrophic, mid-latitude beta-plane model with a constant background westerly wind and a prescribed N^(2) applicable to the stratosphere is used to obtain analytic solutions. In this model, the planetary waves are initiated by steady energy influx from the lower boundary. The analysis indicates that under strong N^(2) conditions, the amplitude of planetary waves can be sufficiently increased by the effective energy convergence due to the slowing vertical energy transfer, resulting in a streamfunction response in this model that contains more energy. For N^(2) with a quasi-linear vertical variation, the results bear a resemblance to the constant case, except that the wave amplitude and oscillating frequency show some vertical variations.展开更多
Based on high-altitude and ground observation data and physical quantity field data,the diagnostic analysis of a heavy rainfall process in Hulunbuir City from July 18 to 20,2025 was conducted from the aspects of circu...Based on high-altitude and ground observation data and physical quantity field data,the diagnostic analysis of a heavy rainfall process in Hulunbuir City from July 18 to 20,2025 was conducted from the aspects of circulation patterns,influencing systems,dynamic conditions,moisture conditions and convective conditions,and the causes of the occurrence and development of this process were revealed.The study shows that the superposition of the upper-level trough,the ground cyclone,and the low-level jet stream formed strong water vapor transport,strong warm advection,and strong dynamic uplift in Hulunbuir,thereby leading to this heavy rainfall event.The forecasting ideas for short-term heavy rainfall were pointed out to provide certain scientific references for future forecasting and prediction work.展开更多
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
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
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
BACKGROUND:Prolonged on-scene Advanced Life Support(ALS) in out-of-hospital cardiac arrest(OHCA) patients may enhance return of spontaneous circulation(ROSC),but the optimal duration of cardiopulmonary resuscitation(C...BACKGROUND:Prolonged on-scene Advanced Life Support(ALS) in out-of-hospital cardiac arrest(OHCA) patients may enhance return of spontaneous circulation(ROSC),but the optimal duration of cardiopulmonary resuscitation(CPR) without initial prehospital ROSC remains unclear.We investigated the association between on-scene CPR duration and outcomes using nationwide data.METHODS:This prospective,multi-regional study(2015–2022) included medical cause OHCA patients who underwent Smart ALS(SALS).Data from emergency medical services(EMS) records,SALS logs,and hospital outcomes were analyzed.Logistic regression models were developed for prehospital ROSC,survival to discharge,and good neurological outcome(Cerebral Performance Category [CPC] 1–2).RESULTS:Among 98,569 patients,34,989 were SALS-eligible and 16,052 received SALS.Predictors of ROSC included younger age,male sex,public arrest,witnessed arrest,bystander CPR,shockable rhythm,and shorter response/scene times.Longer on-scene CPR reduced probabilities of ROSC,survival,and neurological recovery at hospital discharge.Model AUROCs were 0.697(95%CI 0.676–0.717) for ROSC,0.836(95%CI 0.810–0.861) for survival,and 0.925(95%CI 0.904–0.946) for neurological outcome.CONCLUSION:On-scene CPR duration is a critical prognostic factor in OHCA.The proposed models highlight on-scene predictors that may inform decisions about CPR continuation and support individualized resuscitation strategies.External validation in other EMS systems is warranted.展开更多
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
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
The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,t...The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,the spatiotemporal variations and driving mechanisms of drought in the basin remain unclear.Based on the monthly Standardized Precipitation Evapotranspiration Index(SPEI),this study employed the Run-Length theory to identify drought events in the basin during 1980-2020,applied statistical and time-series analyses to investigate the spatiotemporal variations,trends,periodicity,and persistence of drought,and explored the underlying drivers associated with meteorological factors and large-scale atmospheric circulation patterns.The results showed that droughts in the Yili River Basin are more severe in spring and summer.Droughts in the central and southwestern regions exhibit greater severity,with shorter durations and stronger intensity.Drought conditions have generally worsened(Sen’s slope=−0.146/10 yr),with notable intensification since 2005,especially in the northwestern region.Spring droughts(Sen’s slope=−0.213/10 yr)and summer droughts(Sen’s slope=−0.169/10 yr)have intensified at most stations,while autumn and winter droughts have eased.In the future,droughts are expected to alleviate overall,but summer droughts may continue to intensify.The Yili River Basin exhibits two primary drought periods of 9 yr and 21 yr,with primary periods in autumn(20 yr)and winter(20 yr)being longer than those in spring(10 yr)and summer(17 yr).Finally,droughts are impacted by both meteorological factors and large-scale atmospheric circulation patterns.Rising temperatures and uneven precipitation have intensified droughts.The SPEI exhibits a co-phase relationship with the North Atlantic Oscillation and an antiphase relationship with the East Central Tropical Pacific Sea Surface Temperature.Therefore,close monitoring and mitigation are necessary for spring and summer droughts,with a focus on the central and southwestern areas in autumn and winter.展开更多
The algebraic reconstruction technique(ART),multiplicative algebraic reconstruction technique(MART),and simultaneous iterative reconstruction technique(SIRT)are computational methodologies extensively utilized within ...The algebraic reconstruction technique(ART),multiplicative algebraic reconstruction technique(MART),and simultaneous iterative reconstruction technique(SIRT)are computational methodologies extensively utilized within the field of computerized ionospheric tomography(CIT)to facilitate three-dimensional reconstruction of the ionospheric morphology.However,reconstruction accuracy elicits recurrent disputes over its practical application,and people usually attribute this issue to incomplete and uneven coverage of the measurements.The Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM)offers a reasonable physics-based ionospheric background and is widely utilized in ionospheric research.We use the TIEGCM simulations as the targeted ionosphere because the current measurements are far from able to realistically reproduce the ionosphere in detail.Optimized designations of satellite measurements are conducted to investigate the limiting performance of CIT methods in ionospheric reconstruction.Similar to common practice,electron density distributions from outputs of the International Reference Ionosphere(IRI)model are used as the iterative initial value in CIT applications.The outcomes suggest that despite data coverage,iterative initial conditions also play an essential role in ionospheric reconstruction.In particular,in the longitudinal sectors where the iterative initial height of the F2-layer peak electron density(hmF2)differs substantially from the background densities,none of the three CIT methods can reproduce the exact background profile.When hmF2 is close but the ionospheric F2-layer peak density(NmF2)is different between the targeted background and initial conditions,the MART performs better than the ART and SIRT,as evidenced by the correlation coefficients of MART being above 0.97 and those of ART and SIRT being below 0.85.In summary,this investigation reveals the potential uncertainties in traditional CIT reconstruction,particularly when realistic hmF2 or NmF2 values differ substantially from the initial CIT conditions.展开更多
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
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
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
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
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
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
This paper first analyzes the complexity of pathological processes involved in acute hemorrhagic or ischemic stroke,including primary and secondary brain injury manifestations and mechanisms,potential transformations ...This paper first analyzes the complexity of pathological processes involved in acute hemorrhagic or ischemic stroke,including primary and secondary brain injury manifestations and mechanisms,potential transformations between hemorrhage and infarction,and the impact of postbrain injury inflammation on disease progression.Based on decades of extensive clinical and pharmacological research on the usage of Chinese herbal medicine(CHM)monomers or formulas that promote blood circulation and remove blood stasis(such as Angong Niuhuang Wan,Buyang Huanwu Tang,Dahuoluo Wan,and Dushen Tang)for stroke treatment,it proposes that tonifying qi,promoting blood circulation,removing blood stasis,and detoxifying are rational treatment principles of CHM.These principles correspond to the following Western medical implications:tonifying qi corresponds to neuroprotection effects,promoting blood circulation corresponds to anticoagulation and thrombolysis,removing blood stasis addresses hematoma absorption and cerebral edema reduction,and detoxifying corresponds to anti-inflammatory actions.This paper further proposes from a systems medicine perspective that acute stroke is a complex disease requiring individualized CHM treatment with timely modifications rather than a one-sizefits-all approach.CHM monomers or formulas for promoting blood circulation and removing blood stasis,which have various effects such as lowering blood pressure,hemostasis,anticoagulation,antiplatelet,anti-inflammatory,promoting fibrinolysis,and edema reduction,must align with disease progression and be applied within appropriate therapeutic time windows to ensure efficacy and safety.Finally,this paper suggests that a combined use of acupuncture and CHM can potentially synergistically leverage their respective therapeutic strengths.Additionally,acupuncture shows clear benefits in the acute phase of intracerebral hemorrhage(ICH),such as stimulating the vagus nerve to enhance cerebral blood flow,reducing inflammation,as well as triggering hemostatic effects.By applying these rational treatment principles in an integrated approach,better CHM treatment outcomes and higher efficacy of stroke management may be attained.展开更多
基金supported by the National Key R&D Program of China,No.2021YFC2501200(to PC).
文摘Short-chain fatty acids,metabolites produced by the fermentation of dietary fiber by gut microbiota,have garnered significant attention due to their correlation with neurodegenerative diseases,particularly Parkinson’s disease.In this review,we summarize the changes in short-chain fatty acid levels and the abundance of short-chain fatty acid-producing bacteria in various samples from patients with Parkinson’s disease,highlighting the critical role of gut homeostasis imbalance in the pathogenesis and progression of the disease.Focusing on the nervous system,we discuss the molecular mechanisms by which short-chain fatty acids influence the homeostasis of both the enteric nervous system and the central nervous system.We identify key processes,including the activation of G protein-coupled receptors and the inhibition of histone deacetylases by short-chain fatty acids.Importantly,structural or functional disruptions in the enteric nervous system mediated by these fatty acids may lead to abnormalα-synuclein expression and gastrointestinal dysmotility,which could serve as an initiating event in Parkinson’s disease.Furthermore,we propose that short-chain fatty acids help establish communication between the enteric nervous system and the central nervous system via the vagal nerve,immune circulation,and endocrine signaling.This communication may shed light on their potential role in the transmission ofα-synuclein from the gut to the brain.Finally,we elucidate novel treatment strategies for Parkinson’s disease that target short-chain fatty acids and examine the challenges associated with translating short-chain fatty acid-based therapies into clinical practice.In conclusion,this review emphasizes the pivotal role of short-chain fatty acids in regulating gut-brain axis integrity and their significance in the pathogenesis of Parkinson’s disease from the perspective of the nervous system.Moreover,it highlights the potential value of short-chain fatty acids in early intervention for Parkinson’s disease.Future research into the molecular mechanisms of short-chain fatty acids and their synergistic interactions with other gut metabolites is likely to advance the clinical translation of innovative short-chain fatty acid-based therapies for Parkinson’s disease.
基金supported by the National Natural Science Foundation of China(Grant Nos.U2342210 and 42275043)the National Institute of Natural Hazards,Ministry of Emergency Management of China(Grant Nos.J2223806,ZDJ2024-25 and ZDJ2025-34)。
文摘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.
基金supported by the Open Research Fund of Key Laboratory for Lake Pollution Control of the Ministry of Ecology and Environment(No.2024HPYKFZD04)the Fundamental Research Funds for the Central Publicinterest Scientific Institution(No.2025YSKY-04)the National Natural Science Foundation of China(Nos.U1902207 and 42207265).
文摘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.
基金supported by the National Natural Science Foundation of China(Grant No.42261134532,42405059,and U2342212)。
文摘This study investigates the relationship between atmospheric stratification (i.e., static stability given by N^(2)) and the vertical energy transfer of stationary planetary waves, and further illustrates the underlying physical mechanism. Specifically, for the simplified case of constant stratospheric N^(2), the refractive index square of planetary waves has a theoretical tendency to increase first and then decrease with an increased N^(2), whereas the group velocity weakens. Mechanistically, this behavior can be understood as an intensified suppression of vertical isentropic surface displacement caused by meridional heat transport of planetary waves under strong N^(2) conditions. Observational analysis corroborates this finding, demonstrating a reduction in the vertical-propagation velocity of waves with increased N^(2). A linear, quasi- geostrophic, mid-latitude beta-plane model with a constant background westerly wind and a prescribed N^(2) applicable to the stratosphere is used to obtain analytic solutions. In this model, the planetary waves are initiated by steady energy influx from the lower boundary. The analysis indicates that under strong N^(2) conditions, the amplitude of planetary waves can be sufficiently increased by the effective energy convergence due to the slowing vertical energy transfer, resulting in a streamfunction response in this model that contains more energy. For N^(2) with a quasi-linear vertical variation, the results bear a resemblance to the constant case, except that the wave amplitude and oscillating frequency show some vertical variations.
文摘Based on high-altitude and ground observation data and physical quantity field data,the diagnostic analysis of a heavy rainfall process in Hulunbuir City from July 18 to 20,2025 was conducted from the aspects of circulation patterns,influencing systems,dynamic conditions,moisture conditions and convective conditions,and the causes of the occurrence and development of this process were revealed.The study shows that the superposition of the upper-level trough,the ground cyclone,and the low-level jet stream formed strong water vapor transport,strong warm advection,and strong dynamic uplift in Hulunbuir,thereby leading to this heavy rainfall event.The forecasting ideas for short-term heavy rainfall were pointed out to provide certain scientific references for future forecasting and prediction work.
基金National Natural Science Foundation of China(42375153,42105153,42205157)Development of Science and Technology at Chinese Academy of Meteorological Sciences(2023KJ038)。
文摘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.
基金supported by the National Natural Science Foundation of China [grant number 92358302]。
文摘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.
基金supported by the National Natural Science Foundation of China(Grant No.42275041)the Hainan Province Science and Technology Special Fund(Grant No.SOLZSKY2025006).
文摘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.
基金supported by Soonchunhyang University research fund。
文摘BACKGROUND:Prolonged on-scene Advanced Life Support(ALS) in out-of-hospital cardiac arrest(OHCA) patients may enhance return of spontaneous circulation(ROSC),but the optimal duration of cardiopulmonary resuscitation(CPR) without initial prehospital ROSC remains unclear.We investigated the association between on-scene CPR duration and outcomes using nationwide data.METHODS:This prospective,multi-regional study(2015–2022) included medical cause OHCA patients who underwent Smart ALS(SALS).Data from emergency medical services(EMS) records,SALS logs,and hospital outcomes were analyzed.Logistic regression models were developed for prehospital ROSC,survival to discharge,and good neurological outcome(Cerebral Performance Category [CPC] 1–2).RESULTS:Among 98,569 patients,34,989 were SALS-eligible and 16,052 received SALS.Predictors of ROSC included younger age,male sex,public arrest,witnessed arrest,bystander CPR,shockable rhythm,and shorter response/scene times.Longer on-scene CPR reduced probabilities of ROSC,survival,and neurological recovery at hospital discharge.Model AUROCs were 0.697(95%CI 0.676–0.717) for ROSC,0.836(95%CI 0.810–0.861) for survival,and 0.925(95%CI 0.904–0.946) for neurological outcome.CONCLUSION:On-scene CPR duration is a critical prognostic factor in OHCA.The proposed models highlight on-scene predictors that may inform decisions about CPR continuation and support individualized resuscitation strategies.External validation in other EMS systems is warranted.
基金supported by the National Key Research and Development Program of China (2021YFD1800200)the National Natural Science Foundation of China (32170539)。
文摘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).
基金supported by the Science and Technology Innovation Program of Hunan Province(Nos.2023RC1025 and 2024RC3022)the Technology Special Program Project of China Minmetals Corporation(No.2021ZXA04)the Major Scientific Research Projects of Inner Mongolia Baotou Steel Union Co.,Ltd.(No.HKF202300356).
文摘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.
基金Under the auspices of the Third Xinjiang Scientific Expedition Program(No.2022xjkk0600)。
文摘The Yili River Basin in Northwest China is a crucial ecological security barrier,yet it faces frequent droughts amid global climate change,posing significant threats to food security and ecological stability.However,the spatiotemporal variations and driving mechanisms of drought in the basin remain unclear.Based on the monthly Standardized Precipitation Evapotranspiration Index(SPEI),this study employed the Run-Length theory to identify drought events in the basin during 1980-2020,applied statistical and time-series analyses to investigate the spatiotemporal variations,trends,periodicity,and persistence of drought,and explored the underlying drivers associated with meteorological factors and large-scale atmospheric circulation patterns.The results showed that droughts in the Yili River Basin are more severe in spring and summer.Droughts in the central and southwestern regions exhibit greater severity,with shorter durations and stronger intensity.Drought conditions have generally worsened(Sen’s slope=−0.146/10 yr),with notable intensification since 2005,especially in the northwestern region.Spring droughts(Sen’s slope=−0.213/10 yr)and summer droughts(Sen’s slope=−0.169/10 yr)have intensified at most stations,while autumn and winter droughts have eased.In the future,droughts are expected to alleviate overall,but summer droughts may continue to intensify.The Yili River Basin exhibits two primary drought periods of 9 yr and 21 yr,with primary periods in autumn(20 yr)and winter(20 yr)being longer than those in spring(10 yr)and summer(17 yr).Finally,droughts are impacted by both meteorological factors and large-scale atmospheric circulation patterns.Rising temperatures and uneven precipitation have intensified droughts.The SPEI exhibits a co-phase relationship with the North Atlantic Oscillation and an antiphase relationship with the East Central Tropical Pacific Sea Surface Temperature.Therefore,close monitoring and mitigation are necessary for spring and summer droughts,with a focus on the central and southwestern areas in autumn and winter.
基金supported by the National Key R&D Program of China (Grant No. 2022YFF0503702)the National Natural Science Foundation of China (Grant No. 42074186)
文摘The algebraic reconstruction technique(ART),multiplicative algebraic reconstruction technique(MART),and simultaneous iterative reconstruction technique(SIRT)are computational methodologies extensively utilized within the field of computerized ionospheric tomography(CIT)to facilitate three-dimensional reconstruction of the ionospheric morphology.However,reconstruction accuracy elicits recurrent disputes over its practical application,and people usually attribute this issue to incomplete and uneven coverage of the measurements.The Thermosphere Ionosphere Electrodynamics General Circulation Model(TIEGCM)offers a reasonable physics-based ionospheric background and is widely utilized in ionospheric research.We use the TIEGCM simulations as the targeted ionosphere because the current measurements are far from able to realistically reproduce the ionosphere in detail.Optimized designations of satellite measurements are conducted to investigate the limiting performance of CIT methods in ionospheric reconstruction.Similar to common practice,electron density distributions from outputs of the International Reference Ionosphere(IRI)model are used as the iterative initial value in CIT applications.The outcomes suggest that despite data coverage,iterative initial conditions also play an essential role in ionospheric reconstruction.In particular,in the longitudinal sectors where the iterative initial height of the F2-layer peak electron density(hmF2)differs substantially from the background densities,none of the three CIT methods can reproduce the exact background profile.When hmF2 is close but the ionospheric F2-layer peak density(NmF2)is different between the targeted background and initial conditions,the MART performs better than the ART and SIRT,as evidenced by the correlation coefficients of MART being above 0.97 and those of ART and SIRT being below 0.85.In summary,this investigation reveals the potential uncertainties in traditional CIT reconstruction,particularly when realistic hmF2 or NmF2 values differ substantially from the initial CIT conditions.
基金supported by the National Natural Science Foundation of China(42250101,42250102)the Macao Foundation.
文摘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.
基金support from the National Natural Science Foundation of China(Grant No.52274009).
文摘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.
文摘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.
基金supported by the National Natural Science Foundation of China(No.52074312)the CNPC Science and Technology Innovation Foundation(No.2021DQ02-0505)+1 种基金the Open Fund Project of the National Key Laboratory for the Enrichment Mechanism and Efficient Development of Shale Oil and Gas(No.36650000-24-ZC0609-0006)the Major Science and Technology Project of Karamay City(No.20232023zdzx0003).
文摘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.
基金National Natural Science Foundation of China:Study on the Intervention Mechanism of Zhilong Huoxue Tongyu Capsule in Hypertensive Myocardial Fibrosis by Regulating Transforming Growth Factor-β/Smad3/Erbb4-IR/miR29b Loop (No.82074378)Project of Science & Technology Department of Sichuan Province:Research on the Optimization of Basic and Clinical Plans for Treating Coronary Heart Disease and Heart Failure based on Xuanfu Theory (No.2022YFS0618)+1 种基金Luzhou Science and Technology Bureau Project:the Mechanism of Hirudin Inhibiting AngⅡInduced Myocardial Hypertrophy by Regulating Autophagy and NOD-like Receptor Family Pyrin Domain Containing Protein 3 Inflammasome (No.2023JYJ029)Southwest Medical University Project:Study on the Mechanism of Zhilong Huoxue Tongyu Capsules in Improving NOD-like Receptor Family Pyrin Domain Containing Protein 3 Inflammasome Mediated Cardiomyocyte Pyroptosis in Heart Failure by Regulating the HippoYes-Associated Protein Pathway (No.2023ZYYQ04)。
文摘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.
基金supported by the National Natural Science Foundation of China[grant numbers U2142207 and U2342205]the National Key R&D Program of China[grant number 2024YFC3013100]China Meteorological Administration(CMA)Youth Innovation Team[CMA2024QN06].
文摘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.
文摘This paper first analyzes the complexity of pathological processes involved in acute hemorrhagic or ischemic stroke,including primary and secondary brain injury manifestations and mechanisms,potential transformations between hemorrhage and infarction,and the impact of postbrain injury inflammation on disease progression.Based on decades of extensive clinical and pharmacological research on the usage of Chinese herbal medicine(CHM)monomers or formulas that promote blood circulation and remove blood stasis(such as Angong Niuhuang Wan,Buyang Huanwu Tang,Dahuoluo Wan,and Dushen Tang)for stroke treatment,it proposes that tonifying qi,promoting blood circulation,removing blood stasis,and detoxifying are rational treatment principles of CHM.These principles correspond to the following Western medical implications:tonifying qi corresponds to neuroprotection effects,promoting blood circulation corresponds to anticoagulation and thrombolysis,removing blood stasis addresses hematoma absorption and cerebral edema reduction,and detoxifying corresponds to anti-inflammatory actions.This paper further proposes from a systems medicine perspective that acute stroke is a complex disease requiring individualized CHM treatment with timely modifications rather than a one-sizefits-all approach.CHM monomers or formulas for promoting blood circulation and removing blood stasis,which have various effects such as lowering blood pressure,hemostasis,anticoagulation,antiplatelet,anti-inflammatory,promoting fibrinolysis,and edema reduction,must align with disease progression and be applied within appropriate therapeutic time windows to ensure efficacy and safety.Finally,this paper suggests that a combined use of acupuncture and CHM can potentially synergistically leverage their respective therapeutic strengths.Additionally,acupuncture shows clear benefits in the acute phase of intracerebral hemorrhage(ICH),such as stimulating the vagus nerve to enhance cerebral blood flow,reducing inflammation,as well as triggering hemostatic effects.By applying these rational treatment principles in an integrated approach,better CHM treatment outcomes and higher efficacy of stroke management may be attained.
