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Ballistic magnon circulators with magnetic skyrmions
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作者 Haichuan Zhang Hongbin Wu Jin Lan 《Chinese Physics B》 2025年第10期75-82,共8页
Spin waves,quantized as magnons,constitute a fundamental class of excitations and serve as one of the primary angular momentum carriers in magnetic systems.Devoid of Joule heating,a magnonic device that routes spin wa... Spin waves,quantized as magnons,constitute a fundamental class of excitations and serve as one of the primary angular momentum carriers in magnetic systems.Devoid of Joule heating,a magnonic device that routes spin waves between different ports holds promise for an energy-efficient information infrastructure.Here,we systematically investigate the transport behavior of a magnetic skyrmion-based magnon circulator,a representative device that directs spin wave flow in a non-reciprocal manner.Particularly,a ballistic transport model is established,where the scattering of spin waves by magnetic skyrmions is simplified as magnon deflection by fictitious electromagnetic fields within the skyrmions.Through the combination of ballistic analyses and micromagnetic simulations,the circulation performance is rigorously evaluated for multiple magnon circulators. 展开更多
关键词 spin wave ballistic transport magnetic skyrmion CIRCULATOR
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Preparation and Magnetic Properties of SrFe12O19 Ferrites Suitable for Use in Self-Biased LTCC Circulators 被引量:1
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作者 彭龙 胡跃斌 +4 位作者 郭成 李乐中 王瑞 胡云 涂小强 《Chinese Physics Letters》 SCIE CAS CSCD 2015年第1期150-153,共4页
Strontium ferrites with different Bi2O3 content are prepared by the solid phase method, and their magnetic properties are investigated primarily. The Bi2O3 additive and sintering temperature separately exhibit a stron... Strontium ferrites with different Bi2O3 content are prepared by the solid phase method, and their magnetic properties are investigated primarily. The Bi2O3 additive and sintering temperature separately exhibit a strong effect on the sintering density, crystal structure, and magnetic properties of the ferrites. As to the ferrites with 3 wt% Bi2O3, the relatively high sintering density ρs, saturation magnetization Ms, and intrinsic coercivity HCi can be obtained at a low sintering temperature of 900℃ even much lower. Furthermore, the effective magnetic anisotropy constant Keff and magnetic anisotropy field Ha of the ferrites are calculated from the magnetization curve by the law of approach to saturation. It is suggested that the low-temperature sintered SrFe12O19 ferrites with Ms of 285.6 kA/m and Ha of 1564.6 kA/m possess a significant potentiality for applying in the self-biased low-temperature co-fired ceramics circulators from 34 to 40GHz. 展开更多
关键词 Bi Preparation and Magnetic Properties of SrFe Ferrites Suitable for Use in Self-Biased LTCC circulators
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A New Design Method for the Octave-Band Stripline Circulators
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作者 Pan YongjiBeijing Institute of Radio Measurement, P.O.Box 3923, Beijing 100854, China 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 1994年第4期33-39,共7页
In this paper, a new design method for high performance octave-band stripline circulator is given. The optimum design program is given by a construction with double-Y junction aided by a section of quarter-wavelength ... In this paper, a new design method for high performance octave-band stripline circulator is given. The optimum design program is given by a construction with double-Y junction aided by a section of quarter-wavelength impedance transformer. All the calculation is simpler than that given by Y. S. Wu, et al[1-7]. Typical performances of the 2-4GHz Y-junction stripline circulator are insertion loss 0.35dB (max), isolation 21dB (min), VSWR 1.25 (max). An octave low-loss and high isolation performance is demonstrated without the need of repeated design cycles. 展开更多
关键词 Octave-band stripline circulator Double Y Junction.
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CPW Circulators with Barium Ferrite Thin Films
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作者 Yuan Wang Bin Peng +1 位作者 Wan-Li Zhang Ke Tan 《Journal of Electronic Science and Technology》 CAS 2010年第4期351-355,共5页
A miniaturized circulator using barium ferrite films with a coplanar waveguide(CPW)structure is designed and optimized by high frequency electromagnetic field simulations based on finite element methods.The best circu... A miniaturized circulator using barium ferrite films with a coplanar waveguide(CPW)structure is designed and optimized by high frequency electromagnetic field simulations based on finite element methods.The best circulation performance of the film circulator based on 10 pm thick barium ferrite thin films is obtained with an insertion loss of 0.13 dB and an isolation of 22.89 dB around 36.9 GHz.The microwave characteristics of film circulators with CPW and CPW with ground(CPWG)structures have been compared.The influences of the gap between the ground and the signal line,and the ferromagnetic resonance line width on the microwave properties are also studied. 展开更多
关键词 circulators coplanar waveguide millimeter wave passive microwave components.
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Short-chain fatty acids mediate enteric and central nervous system homeostasis in Parkinson’s disease:Innovative therapies and their translation 被引量:1
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作者 Shimin Pang Zhili Ren +1 位作者 Hui Ding Piu Chan 《Neural Regeneration Research》 2026年第3期938-956,共19页
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
关键词 ALPHA-SYNUCLEIN blood-brain barrier blood circulation central nervous system ENDOCRINE enteric nervous system glial cell gut-brain axis gut microbiota intestinal barrier neuron Parkinson’s disease short chain fatty acids vagus nerve
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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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Vertical Structure and Energy Transfer of Stationary Planetary Waves in Different Prescribed Atmospheric Stratifications
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作者 Wenqi ZHANG Lin WANG 《Advances in Atmospheric Sciences》 2026年第1期233-246,共14页
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
关键词 planetary waves vertical propagation atmospheric stratification stratospheric circulation group velocity
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EXACT ELECTROMAGNETIC FIELD THEORY FOR BROADBAND H-PLANE WAVEGUIDE JUNCTION CIRCULATORS
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作者 窦文斌 《Science China Mathematics》 SCIE 1989年第9期1115-1127,共13页
This paper analyses the broadband H-plane waveguide junction circulators with the metal step and partial-height ferrite post. Using the field match method, the eigenmodes are given to expand the electromagnetic field ... This paper analyses the broadband H-plane waveguide junction circulators with the metal step and partial-height ferrite post. Using the field match method, the eigenmodes are given to expand the electromagnetic field in ferrite. The eigenmodes include not only the volume modes in literatures, but also the surface modes derived in this paper. Two sets of modes are used in analysis. The match between junction and waveguides is simplified, using a synthetic method, combining the electromagnetic field theory with the eigenvalue theory of the symmetric network scattering matrix and the transmission line theory. In an 8-mm band, the calculated bandwidth is 19% with 20-dBisolatioa. Computation and experiments are in good agreement. The calculated results display n=2 Chebyshev response characteristics. 展开更多
关键词 BROADBAND WAVEGUIDE CIRCULATOR VOLUME MODES surface modes.
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Excess Loss of the Coupling System to Double-Function Optical Circulators Utilizing Lens Twice and Two-Fiber Tips
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作者 TIAN Yan-ning FANG Qiang +3 位作者 WANG Yong-chang SUN Ai-jing BAI Ju-rong YANG Yi-fei 《The Journal of China Universities of Posts and Telecommunications》 EI CSCD 2005年第3期49-53,共5页
A new type of double function optical circulator for double fibers is proposed in this paper. Two fiber tips and lens twice are employed in this kind of device as the coupling system for what is believed to be the fir... A new type of double function optical circulator for double fibers is proposed in this paper. Two fiber tips and lens twice are employed in this kind of device as the coupling system for what is believed to be the first time. Because two fiber tips and lens twice are used, the function of optical circulator is duplicated in comparison with conventional optical circulator with single fiber tip. Thus the optical circulator has a low cost and a small volume comparatively. Excess loss of the coupling system and the misalignment of the lens twice in angular error and the position error to the developed circulator are analyzed and discussed by using Gauss wave and double integral in theory. The analysis results show that the excess loss is zero when each distance is equal to f between every adjacent: fraction and without misalignment error in the coupling system. In addition, the excess loss is increasing with increment of the distance error and the angular error. The errors of the angular of the optical axis to lens and the distance between the SL to lens are the main source of the excess loss. The higher the errors are, the higher the excess loss is. It's very important for reducing the misalignment errors in the coupling system with high ratio of coupling to achieve low excess loss. Details of design and excess loss in the coupling system of this circulator are presented. 展开更多
关键词 optical circulator double fiber tips lens twice double Integral excess loss
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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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Cholangiocarcinoma:The era of liquid biopsy 被引量:1
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作者 Evgenia Kotsifa Francesca Saffioti Vasileios K Mavroeidis 《World Journal of Gastroenterology》 2025年第11期14-32,共19页
Cholangiocarcinoma(CCA)is a highly aggressive and heterogeneous malignancy arising from the epithelial cells of the biliary tract.The limitations of the current methods in the diagnosis of CCA highlight the urgent nee... Cholangiocarcinoma(CCA)is a highly aggressive and heterogeneous malignancy arising from the epithelial cells of the biliary tract.The limitations of the current methods in the diagnosis of CCA highlight the urgent need for new,accurate tools for early cancer detection,better prognostication and patient monitoring.Liquid biopsy(LB)is a modern and non-invasive technique comprising a diverse group of methodologies aiming to detect tumour biomarkers from body fluids.These biomarkers include circulating tumour cells,cell-free DNA,circulating tumour DNA,RNA and extracellular vesicles.The aim of this review is to explore the current and potential future applications of LB in CCA management,with a focus on diagnosis,prognostication and monitoring.We examine both its significant potential and the inevitable limitations associated with this technology.We conclude that LB holds considerable promise,but further research is necessary to fully integrate it into precision oncology for CCA. 展开更多
关键词 Biliary tract cancer CHOLANGIOCARCINOMA Circulating tumour cells Cell free DNA Circulating tumour DNA Circulating RNA Biomarkers Extracellular vesicles Precision medicine
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Detecting plasma SHOX2, HOXA9, SEPTIN9, and RASSF1A methylation and circulating cancer cells for cholangiocarcinoma clinical diagnosis and monitoring 被引量:1
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作者 Jing Yu Qiu-Chen Liu +2 位作者 Shuang-Yan Lu Shun Wang Hua Zhang 《World Journal of Gastrointestinal Oncology》 2025年第4期210-222,共13页
BACKGROUND Cholangiocarcinoma(CCA),also known as bile duct cancer,is a devastating malignancy primarily affecting the biliary tract.AIM To assess their performance in clinical diagnosis and monitoring of CCA,plasma me... BACKGROUND Cholangiocarcinoma(CCA),also known as bile duct cancer,is a devastating malignancy primarily affecting the biliary tract.AIM To assess their performance in clinical diagnosis and monitoring of CCA,plasma methylation and circulating tumor cells were detected.METHODS Plasma samples were collected from Hubei Cancer Hospital(n=156).Plasma DNA was tested to detect SHOX2,HOXA9,SEPTIN9,and RASSF1A methylation using TaqMan PCR.Circulating tumor cells(CTCs)were detected in the peripheral blood of patients using the United States Food and Drug Administration-approved cell search system before and after clinical therapy.The CCA diagnostic value was estimated using the area under the curve.The independent prognosis risk factors for patients with CCA were estimated using Cox and logistic regression analyses.RESULTS The sensitivity and specificity of the four DNA plasma methylations exhibited 64.74%sensitivity and 93.88%specificity for detecting CCA.The receiver operating characteristic curve of the combined value for CCA diagnosis in plasma was 0.828±0.032.RASSF1A plasma methylation was related to the prognosis of patients with CCA.We determined the prognostic hazard ratio for CCA using CTC count,tumor stage,methylation,and carbohydrate antigen 19-9 levels as key factors.Our overall survival nomogram achieved a C-index of 0.705(0.605-0.805).CONCLUSION SHOX2,HOXA9,SEPTIN9,and RASSF1A plasma methylation demonstrated increased sensitivity for diagnosing CCA.RASSF1A plasma methylation and CTCs were valuable predictors to assess CCA prognosis and recurrence. 展开更多
关键词 CHOLANGIOCARCINOMA METHYLATION Circulating cancer cells Diagnosis PROGNOSIS
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Personalized surveillance in colorectal cancer:Integrating circulating tumor DNA and artificial intelligence into post-treatment follow-up 被引量:1
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作者 Ionut Negoi 《World Journal of Gastroenterology》 2025年第18期1-9,共9页
Given the growing burden of colorectal cancer(CRC)as a global health challenge,it becomes imperative to focus on strategies that can mitigate its impact.Posttreatment surveillance has emerged as essential for early de... Given the growing burden of colorectal cancer(CRC)as a global health challenge,it becomes imperative to focus on strategies that can mitigate its impact.Posttreatment surveillance has emerged as essential for early detection of recurrence,significantly improving patient outcomes.However,intensive surveillance strategies have shown mixed results compared to less intensive methods,emphasizing the necessity for personalized,risk-adapted approaches.The observed suboptimal adherence to existing surveillance protocols underscores the urgent need for more tailored and efficient strategies.In this context,circulating tumor DNA(ctDNA)emerges as a promising biomarker with significant potential to revolutionize post-treatment surveillance,demonstrating high specificity[0.95,95%confidence interval(CI):0.91-0.97]and robust diagnostic odds(37.6,95%CI:20.8-68.0)for recurrence detection.Furthermore,artificial intelligence and machine learning models integrating patient-specific and tumor features can enhance risk stratification and optimize surveillance strategies.The reported area under the receiver operating characteristic curve,measuring artificial intelligence model performance in predicting CRC recurrence,ranged from 0.581 and 0.593 at the lowest to 0.979 and 0.978 at the highest in training and validation cohorts,respectively.Despite this promise,addressing cost,accessibility,and extensive validation remains crucial for equitable integration into clinical practice. 展开更多
关键词 Colorectal cancer Post-treatment surveillance Tumor recurrence Follow-up protocols Circulating tumor DNA Artificial intelligence
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Spatial metabolomics combined with machine learning in colon cancer diagnosis research 被引量:1
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作者 Ling Weng Huanhuan Wang +5 位作者 Chunxiang Zhai Qi Wang Yanyan Guo Ziyi Zhong Chenying Ma Jing Wang 《Journal of Pharmaceutical Analysis》 2025年第8期1937-1938,共2页
Colon cancer is one of the malignant tumors with high morbidity and mortality worldwide[1],and its early diagnosis is crucial for improving patient survival.However,due to the lack of obvious early symptoms of colon c... Colon cancer is one of the malignant tumors with high morbidity and mortality worldwide[1],and its early diagnosis is crucial for improving patient survival.However,due to the lack of obvious early symptoms of colon cancer,many patients are in the middle to late stage when diagnosed and miss the best time for treatment.Therefore,developing an efficient and accurate diagnostic method for colon cancer is of great clinical significance and scientific value.Currently,the current colon cancer biomarkers carcinoembryonic antigen and carbohydrate antigen 19-9[2]have low sensitivity and specificity,the emerging markers circulating tumor DNA(ctDNA)and miRNA face high cost and standardization challenges,and the existing methods lack spatial resolution,prompting the incorporation of spatial metabolomics technologies to enhance diagnostic capabilities. 展开更多
关键词 machine learning colon cancer diagnosis miRNA colon cancer spatial metabolomics malignant tumors circulating tumor DNA biomarkers
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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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The Pathological Complexity of Stroke and Rational Treatment Principles of Chinese Herbal Medicine 被引量:1
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作者 Guanyuan Jin Louis Lei Jin Belinda Jie He 《Chinese Medicine and Natural Products》 2025年第1期1-22,共22页
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
关键词 stroke-chinese herbal medicine tonifying qi promoting blood circulation removing blood stasis detoxifying anti-inflammatory therapeutic time windows treatment with timely modification
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Accurate quantification of the algebraic,multiplicative algebraic,and simultaneous iterative reconstruction techniques in ionosphere rebuilding based on the TIEGCM assessment
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作者 Ao Qi HaiBing Ruan 《Earth and Planetary Physics》 EI CAS 2025年第1期117-126,共10页
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
关键词 computerized ionospheric tomography International Reference Ionosphere model Thermosphere Ionosphere Electrodynamics General Circulation model IONOSPHERE
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Effects of exercise on inflammation,circulating tumor cells,and circulating tumor DNA in colorectal cancer
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作者 Justin C.Brown Stephanie L.E.Compton +6 位作者 Andrew Kang Anjana Jayaraman LAnne Gilmore Brian J.Kirby Frank L.Greenway Shengping Yang Guillaume Spielmann 《Journal of Sport and Health Science》 2025年第6期33-41,166,共10页
Background The biological mechanisms by which postdiagnosis physical activity improves disease-free survival in colorectal cancer survivors remain incompletely understood.This trial tested the hypothesis that 12 weeks... Background The biological mechanisms by which postdiagnosis physical activity improves disease-free survival in colorectal cancer survivors remain incompletely understood.This trial tested the hypothesis that 12 weeks of moderate-intensity aerobic exercise,when compared with a control group,would change inflammation,circulating tumor cells(CTCs),and circulating tumor DNA(ctDNA)in a manner consistent with an improved cancer prognosis.Methods This trial randomized Stages I–III colorectal cancer survivors to 12 weeks of home-based moderate-intensity aerobic exercise or a waitlist control group.The co-primary endpoints were high-sensitivity C-reactive protein(hs-CRP)and interleukin-6(IL-6),secondary endpoints were soluble tumor necrosis factor-αreceptor 2(sTNFαR2)and CTCs,and the exploratory endpoint was tumor fraction quantified from ctDNA.Results Sixty subjects were randomized(age=60.6±10.8 years,mean±SD;39(65%)females;46(77%)colonic primary tumor),and 59(98%)subjects completed the study.Over 12 weeks,exercise adherence was 92%(95%confidence interval(95%CI):86‒99).Exercise improved submaximal fitness capacity(0.36 metabolic equivalents;95%CI:0.05‒0.67;p=0.025)and objectively measured moderate-to-vigorous-intensity physical activity(34.8%,95%CI:11.3‒63.1;p=0.002)compared to control.Exercise did not change hs-CRP(20.9%,95%CI:−17.1 to 76.2;p=0.32),IL-6(11.4%,95%CI:−7.5 to 34.0;p=0.25),or sTNFαR2(−3.6%,95%CI:−13.7 to 7.7;p=0.52)compared to control.In the subgroup of subjects with elevated baseline hs-CRP(n=35,58.3%),aerobic exercise reduced hs-CRP(−35.5%,95%CI:−55.3 to−3.8;p=0.031).Exercise did not change CTCs(0.59 cells/mL,95%CI:−0.33 to 1.51;p=0.21)or tumor fraction(0.0005,95%CI:−0.0024 to 0.0034;p=0.73).In exploratory analyses,higher aerobic exercise adherence correlated with a reduction in CTCs(ρ=−0.37,95%CI:−0.66 to−0.08;p=0.013).Conclusion Colorectal cancer survivors achieved high adherence to a home-based moderate-intensity aerobic exercise prescription that improved fitness capacity and physical activity but did not reduce inflammation or change tumor endpoints from a liquid biopsy. 展开更多
关键词 Colorectal neoplasm Physical activity Circulating tumor cells CYTOKINES Circulating tumor DNA
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Plugging mode of flaky lost circulation materials within fractures and mechanism to enhance pressure-bearing capacity for the plugging zone
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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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