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抗精神病药物致猝死与QTc和Torsade de Pointes综合征的相关性 被引量:6
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作者 周小东 黄宣银 李建勋 《四川精神卫生》 2003年第1期63-64,W001-W004,共6页
关键词 抗精神病药物 猝死 QTC Torsade DE pointes综合征 相关性
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Exercise-induced torsades de pointes as an unusual presentation of cardiac sarcoidosis: A case report and review of literature
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作者 Chadi Ghafari Frédéric Vandergheynst +2 位作者 Emmanuel Parent Kaoru Tanaka Stéphane Carlier 《World Journal of Cardiology》 CAS 2020年第6期291-302,共12页
BACKGROUND Sarcoidosis is a rare multisystem disease characterized histologically by noncaseating granuloma formation in the affected organ.While cardiac sarcoidosis is found on autopsy in up to 25%of sarcoidosis case... BACKGROUND Sarcoidosis is a rare multisystem disease characterized histologically by noncaseating granuloma formation in the affected organ.While cardiac sarcoidosis is found on autopsy in up to 25%of sarcoidosis cases,it is still underdiagnosed and is associated with a poor prognosis.Although the etiology of sarcoidosis remains unclear,an antigen triggered exaggerated immune response has been hypothesized.Early detection and prompt management of cardiac sarcoidosis remains pivotal.CASE SUMMARY A 60-year-old female,with pulmonary sarcoidosis in remission,presented to the cardiology outpatient clinic for evaluation of weeks-long dyspnea on moderate exertion(New York Heart Association class II)that was relieved by rest.Submaximal exercise stress test showed multifocal ventricular extrasystoles,followed by a self-limiting torsades de pointes.Cardiac magnetic resonance imaging showed nondilated and normotrophic left ventricle with basoseptal and mid-septal dyskinesis.The magnetic resonance imaging-derived left ventricular ejection fraction was 45%.Delayed enhancement showed patchy transmural fibrosis of the septum and hyperenhancement of the papillary muscles,all in favor of extensive cardiac involvement of sarcoidosis.A double-chamber implantable cardiac defibrillator was implanted,and methylprednisolone(12 mg/d)and methotrexate(12.5 mg/wk)treatment was initiated.Follow-up and implantable cardiac defibrillator interrogation showed episodes of asymptomatic nonsustained ventricular tachycardia and an asymptomatic episode of nonsustained ventricular tachycardia ending by the first antitachycardia pacing run.CONCLUSION Along an extensive review of the literature,this unusual case report highlights the importance of early detection of cardiac involvement of sarcoidosis,in order to avoid potential complications and increase survival. 展开更多
关键词 SARCOIDOSIS Cardiac sarcoidosis Torsades de pointes Ventricular tachycardia IMMUNOTHERAPY Case report
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Torsades de pointes episode in a woman with high-grade fever and inflammatory activation: A case report
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作者 Hui Qiu Hong-Wei Li +2 位作者 Shu-Hong Zhang Xiao-Ge Zhou Wei-Ping Li 《World Journal of Clinical Cases》 SCIE 2021年第12期2899-2907,共9页
BACKGROUND QT interval prolongation can induce torsades de pointes(TdP),a potentially fatal ventricular arrhythmia.Recently,an increasing number of non-cardiac drugs have been found to cause QT prolongation and/or TdP... BACKGROUND QT interval prolongation can induce torsades de pointes(TdP),a potentially fatal ventricular arrhythmia.Recently,an increasing number of non-cardiac drugs have been found to cause QT prolongation and/or TdP onset.Moreover,recent findings have demonstrated the key roles of systemic inflammatory activation and fever in promoting long-QT syndrome(LQTS)and TdP development.CASE SUMMARY A 30-year-old woman was admitted with a moderate to high-grade episodic fever for two weeks.The patient was administered with multiple antibiotics after hospitalization but still had repeating fever and markedly elevated C-reactive protein.Once after a high fever,the patient suddenly lost consciousness,and electrocardiogram(ECG)showed transient TdP onset after frequent premature ventricular contraction.The patient recovered sinus rhythm and consciousness spontaneously,and post-TdP ECG revealed a prolonged QTc interval of 560 ms.The patient’s clinical manifestations and unresponsiveness to the antibiotics led to the final diagnosis of adult-onset Still’s disease(AOSD).There was no evidence of cardiac involvement.After the AOSD diagnosis,discontinuation of antibiotics and immediate initiation of intravenous dexamethasone administration resulted in the normal temperature and QTc interval.The genetic analysis identified that the patient and her father had heterozygous mutations in KCNH2(c.1370C>T)and AKAP9(c.7725A>C).During the 2-year follow-up period,the patient had no recurrence of any arrhythmia and maintained normal QTc interval.CONCLUSION This case study highlights the risk of systemic inflammatory activation and antibiotic-induced TdP/LQTS onset.Genetic analysis should be considered to identify individuals at high risk of developing TdP. 展开更多
关键词 Torsades de pointes Long QT syndrome Adult-onset Still’s disease Antibiotics Inflammation Case report
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Torsades de Pointes Secondary to Excessive Loperamide Use
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作者 Joseph S. Van Tuylt Gail Brock +1 位作者 Kristen Bova Campbell Sana M. Al-Khatib 《Journal of Pharmacy and Pharmacology》 2016年第7期322-327,共6页
Abstract: Loperamide is a common, over-the-counter, antidiarrheal medication that has been implicated in cases of ventricular tachycardia. A 32 year-old female patient with a history of opioid abuse and no prior hist... Abstract: Loperamide is a common, over-the-counter, antidiarrheal medication that has been implicated in cases of ventricular tachycardia. A 32 year-old female patient with a history of opioid abuse and no prior history of cardiovascular disease experienced Torsades de pointes. An electrocardiogram at the time of hospital presentation revealed a prolonged QT interval at 636 msec. Diagnostic evaluation was unremarkable for any underlying cardiovascular pathology. Further investigation revealed the patient had been taking 30-40 loperamide 2 mg tablets oral daily for 2 weeks prior to the onset of Torsades de pointes. At high doses, loperamide may prolong the QT interval through antagonism of the human ether-a-go-go potassium current, thus increasing the risk of ventricular arrhythmias. Clinicians should be cautious with administration of high doses of loperamide to all patients, especially patients at high risk for QT interval prolongation. 展开更多
关键词 Torsades de pointes LOPERAMIDE QT prolongation.
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Experimental study on the mechanism of sex difference in the risk of torsade de pointes 被引量:7
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作者 阮燕菲 刘念 +2 位作者 周强 李泱 王琳 《Chinese Medical Journal》 SCIE CAS CSCD 2004年第4期538-541,共4页
Background Torsade de pointes (TdP) is a form of polymorphic ventricular tachycardia featuring prolonged QT intervals. Female gender is associated with an increased risk of TdP. However, the causes of the sex differe... Background Torsade de pointes (TdP) is a form of polymorphic ventricular tachycardia featuring prolonged QT intervals. Female gender is associated with an increased risk of TdP. However, the causes of the sex difference in risk are poorly understood. Recently, transmural dispersion of repolarization (TDR) has been implicated in the genesis of TdP. Consequently, we compared TdP incidence and TDR between male and female rabbit hearts in order to investigate the mechanism of sex difference in TdP risk in rabbits in vitro. Methods By means of monophasic action potential recording techniques, the monophasic action potential of the epicardium, midmyocardium, and endocardium were simultaneously recorded using specially designed plunge-needle electrodes placed across the left ventricular free wall of both female (n=8) and male (n=8) rabbit hearts purfused by the Langendorff method. TdP was induced by bradycardia, d-sotalol, and low-K +, Mg 2+ Tyrode solution. Results TDR measurements in all three myocardial layers of male and female rabbit hearts were (18±2) ms and (21±2) ms, respectively (n=8, P>0.05). After perfusion with d-sotalol, the 90% monophasic action potential duration was prolonged in both male and femlae rabbits. TDR in male and female rabbit hearts increased to (29±2) ms and (61±2) ms, respectively, a difference that is significant. Eight female rabbit hearts had early afterdepolarization and 7 of them developed TdP. Seven male rabbit hearts had early after depolarization, but only one of these hearts developed TdP.Conclusion Greater TDR may play an important role in the higher incidence of TdP in female rabbit hearts. 展开更多
关键词 action potentials torsade de pointes sex characteristics animal experimentation
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PT-MFR:一种基于Point Transformer的CAD模型加工特征识别方法
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作者 何皓辰 方正 +2 位作者 卢政达 肖俊 王颖 《中国科学院大学学报(中英文)》 北大核心 2026年第1期115-124,共10页
加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不... 加工特征识别在计算机辅助设计(CAD)和制造(CAM)中至关重要,是连接CAD和CAM系统的重要环节。研究者们提出了基于规则和基于学习的2类加工特征识别方法,其中基于学习的方法表现更出色且备受关注。然而,现有识别方法面临着几何信息利用不足、加工特征定位不精准、实例分割过程复杂等挑战。针对这些问题,提出PT-MFR,一种基于Point Transformer的CAD模型加工特征识别方法,它执行语义分割和实例分割2个任务,分别预测模型每个面的加工特征语义类别并计算面相似度以分割加工特征实例,综合2个任务得到加工特征识别结果。实验结果表明,提出的方法性能优于现有的其他方法。 展开更多
关键词 加工特征识别 点云 神经网络 Point Transformer
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Neuromodulation techniques for modulating cognitive function:Enhancing stimulation precision and intervention effects
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作者 Hanwen Cao Li Shang +9 位作者 Deheng Hu Jianbing Huang Yu Wang Ming Li Yilin Song Qianzi Yang Yan Luo Ying Wang Xinxia Cai Juntao Liu 《Neural Regeneration Research》 2026年第2期491-501,共11页
Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize... Neuromodulation techniques effectively intervene in cognitive function,holding considerable scientific and practical value in fields such as aerospace,medicine,life sciences,and brain research.These techniques utilize electrical stimulation to directly or indirectly target specific brain regions,modulating neural activity and influencing broader brain networks,thereby regulating cognitive function.Regulating cognitive function involves an understanding of aspects such as perception,learning and memory,attention,spatial cognition,and physical function.To enhance the application of cognitive regulation in the general population,this paper reviews recent publications from the Web of Science to assess the advancements and challenges of invasive and non-invasive stimulation methods in modulating cognitive functions.This review covers various neuromodulation techniques for cognitive intervention,including deep brain stimulation,vagus nerve stimulation,and invasive methods using microelectrode arrays.The non-invasive techniques discussed include transcranial magnetic stimulation,transcranial direct current stimulation,transcranial alternating current stimulation,transcutaneous electrical acupoint stimulation,and time interference stimulation for activating deep targets.Invasive stimulation methods,which are ideal for studying the pathogenesis of neurological diseases,tend to cause greater trauma and have been less researched in the context of cognitive function regulation.Non-invasive methods,particularly newer transcranial stimulation techniques,are gentler and more appropriate for regulating cognitive functions in the general population.These include transcutaneous acupoint electrical stimulation using acupoints and time interference methods for activating deep targets.This paper also discusses current technical challenges and potential future breakthroughs in neuromodulation technology.It is recommended that neuromodulation techniques be combined with neural detection methods to better assess their effects and improve the accuracy of non-invasive neuromodulation.Additionally,researching closed-loop feedback neuromodulation methods is identified as a promising direction for future development. 展开更多
关键词 acupuncture points ATTENTION brain COGNITION efficiency electrical stimulation MICROELECTRODES movement disorders nervous system PERCEPTION
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Home,Sweet Home:A young returnee is breathing new life into a Chinese village-and finding purpose
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作者 ANTONY HARDI 《ChinAfrica》 2026年第2期28-30,共3页
History has never been driven by comfort,nor shaped solely by inheritance.Its most significant turning points have emerged from those with youth,conviction and courage ingrained in them.Progress starts when young peop... History has never been driven by comfort,nor shaped solely by inheritance.Its most significant turning points have emerged from those with youth,conviction and courage ingrained in them.Progress starts when young people not only dream but also take action.Sometimes,the boldest move is not to run towards the glow of cities,but to turn back-to one’s soil,roots and forgotten home-and help it to flourish. 展开更多
关键词 new life city glow historical turning points action CONVICTION Chinese village youth courage
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Storied Street,Fresh Faces
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作者 XIA YUANYUAN 《ChinAfrica》 2026年第3期31-33,共3页
Local residents,international artists and entrepreneurs are converging on Haikou’s historical Qilou Street,writing a new chapter of openness in Hainan More than 100 years ago,the area along Qilou(Sotto Portico)Street... Local residents,international artists and entrepreneurs are converging on Haikou’s historical Qilou Street,writing a new chapter of openness in Hainan More than 100 years ago,the area along Qilou(Sotto Portico)Street in Haikou,the capital of Hainan Province,served as the embarkation point for Hainanese setting out on their maritime voyages to seek greener pastures. 展开更多
关键词 OPENNESS international artists ENTREPRENEURS Haikou historical Qilou Street maritime voyages embarkation point Hainanprovince
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Ultrastructure and key identification points of fossilized Os Draconis in traditional Chinese medicine
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作者 Dong-Han Bai Zi Xing +5 位作者 Zi-Hao Zhang Zhi-Jie Zhang Da-Jun Lu Nan-Xi Huang Qiao-Chu Wang Lu Luo 《Traditional Medicine Research》 2026年第1期39-46,共8页
Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewa... Background:The medicinal material known as Os Draconis(Longgu)originates from fossilized remains of ancient mammals and is widely used in treating emotional and mental conditions.However,fossil resources are nonrenewable,and clinical demand is increasingly difficult to meet,leading to a proliferation of counterfeit products.During prolonged geological burial,static pressure from the surrounding strata severely compromises the microstructural integrity of osteons in Os Draconis,but Os Draconis still largely retains the structural features of mammalian bone.Methods:Using verified authentic Os Draconis samples over 10,000 years old as a baseline,this study summarizes the ultrastructural characteristics of genuine Os Draconis.Employing electron probe microanalysis and optical polarized light microscopy,we examined 28 batches of authentic Os Draconis and 31 batches of counterfeits to identify their ultrastructural differences.Key points for ultrastructural identification of Os Draconis were compiled,and a new identification approach was proposed based on these differences.Results:Authentic Os Draconis exhibited distinct ultrastructural markers:irregularly shaped osteons with traversing fissures,deformed/displaced Haversian canals,and secondary mineral infill(predominantly calcium carbonate).Counterfeits showed regular osteon arrangements,absent traversal fissures,and homogeneous hydroxyapatite composition.Lab-simulated samples lacked structural degradation features.EPMA confirmed calcium carbonate infill in fossilized Haversian canals,while elemental profiles differentiated lacunae types(void vs.mineral-packed).Conclusion:The study established ultrastructural criteria for authentic Os Draconis identification:osteon deformation,geological fissures penetrating bone units,and heterogenous mineral deposition.These features,unattainable in counterfeits or modern processed bones,provide a cost-effective,accurate identification method.This approach bridges gaps in TCM material standardization and supports quality control for clinical applications. 展开更多
关键词 Os Draconis ULTRASTRUCTURE identification points electron probe polarized light microscope
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Process analysis of columnar dangerous rock mass collapse in the Three Gorges Reservoir Area based on 3D MPM
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作者 CHENG Shulou HUANG Bolin +3 位作者 ZHANG Peng LI Qiuwang DONG Xingchen Qin Panpan 《Journal of Mountain Science》 2026年第1期237-253,共17页
The Three Gorges Reservoir area hosts numerous high-risk columnar rock masses,but predicting their full-process of collapse dynamics in narrow-deep terrains remains challenging.This study investigated the Changdongzi ... The Three Gorges Reservoir area hosts numerous high-risk columnar rock masses,but predicting their full-process of collapse dynamics in narrow-deep terrains remains challenging.This study investigated the Changdongzi columnar dangerous rock mass(CCDRM)through field surveys and simulated its collapse dynamics with Material Point Method(MPM),and analyzed the collapse-diffusionsurge generation mechanisms.Field investigations revealed a 0.8 m-thick lotus-like extrusion structure at the base,severely degraded by cyclic water fluctuations,predisposing the rock mass to base-crushing failure.Numerical simulations indicate collapse velocities up to 42 m/s,amplified spreading with a 318 m deposition range and 11 m maximum thickness,and two major collisions causing 50%-60%velocity reduction.Gully topography buffers kinetic energy,retaining 5%debris on slopes and channeling 7%into the river.High-speed river impact generates a 20 m-diameter cavity,producing an 11 m surge,identifying the Guandukou Town waterfront 1.2 km downstream as a high-risk zone.These results clarify the collapse mechanisms of columnar dangerous rock mass and inform its hazard mitigation strategies. 展开更多
关键词 Dangerous rock mass Material Point Method Three-dimensional numerical simulation Disaster chain SURGE
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A Case of Severe Trauma with Iliac Vascular Injury was Treated using a Time-Based Chain Approach
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作者 Yazheng Shen Lining He +3 位作者 Huifeng Tang Zhiyong Shi Zhen He Ke Guo 《Journal of Clinical and Nursing Research》 2026年第1期380-386,共7页
Severe trauma often involves complex injuries,leading to high disability and fatality rates.Effective treatment requires prompt and coordinated efforts across multiple disciplines to enhance success rates.Time-based c... Severe trauma often involves complex injuries,leading to high disability and fatality rates.Effective treatment requires prompt and coordinated efforts across multiple disciplines to enhance success rates.Time-based chain rescue is crucial in managing severe trauma.A patient with chest and abdominal injuries and hemorrhagic shock was transferred from an ambulance to our hospital.Our trauma team-initiated pre-hospital first aid,utilized an emergency green channel,and conducted rapid ultrasound,collaborating across disciplines.The patient eventually recovered and was discharged. 展开更多
关键词 Severe trauma Hemorrhagic shock Time point of trauma Chain-type treatment
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Structural Reliability Analysis Based on Differential Evolution Algorithm and Hypersphere Integration
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作者 CHEN Zhenzhong HAN Zhuo +4 位作者 WANG Peiyu PAN Qianghua LI Xiaoke GAN Xuehui CHEN Ge 《Journal of Donghua University(English Edition)》 2026年第1期118-130,共13页
In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order relia... In reliability analyses,the absence of a priori information on the most probable point of failure(MPP)may result in overlooking critical points,thereby leading to biased assessment outcomes.Moreover,second-order reliability methods exhibit limited accuracy in highly nonlinear scenarios.To overcome these challenges,a novel reliability analysis strategy based on a multimodal differential evolution algorithm and a hypersphere integration method is proposed.Initially,the penalty function method is employed to reformulate the MPP search problem as a conditionally constrained optimization task.Subsequently,a differential evolution algorithm incorporating a population delineation strategy is utilized to identify all MPPs.Finally,a paraboloid equation is constructed based on the curvature of the limit-state function at the MPPs,and the failure probability of the structure is calculated by using the hypersphere integration method.The localization effectiveness of the MPPs is compared through multiple numerical cases and two engineering examples,with accuracy comparisons of failure probabilities against the first-order reliability method(FORM)and the secondorder reliability method(SORM).The results indicate that the method effectively identifies existing MPPs and achieves higher solution precision. 展开更多
关键词 reliability analysis design point positioning differential evolution algorithm hypersphere integration
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Automated recognition of rock discontinuity in underground engineering using geometric feature analysis
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作者 Adili Rusuli Xiaojun Li +1 位作者 Yuyun Wang Yi Rui 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1016-1033,共18页
Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,su... Discontinuities in rock masses critically impact the stability and safety of underground engineering.Mainstream discontinuities identificationmethods,which rely on normal vector estimation and clustering algorithms,suffer from accuracy degradation,omission of critical discontinuities when orientation density is unevenly distributed,and need manual intervention.To overcome these limitations,this paper introduces a novel discontinuities identificationmethod based on geometric feature analysis of rock mass.By analyzing spatial distribution variability of point cloud and integrating an adaptive region growing algorithm,the method accurately detects independent discontinuities under complex geological conditions.Given that rock mass orientations typically follow a Fisher distribution,an adaptive hierarchical clustering algorithm based on statistical analysis is employed to automatically determine the optimal number of structural sets,eliminating the need for preset clusters or thresholds inherent in traditional methods.The proposed approach effectively handles diverse rock mass shapes and sizes,leveraging both local and global geometric features to minimize noise interference.Experimental validation on three real-world rock mass models,alongside comparisons with three conventional directional clustering algorithms,demonstrates superior accuracy and robustness in identifying optimal discontinuity sets.The proposed method offers a reliable and efficienttool for discontinuities detection and grouping in underground engineering,significantlyenhancing design and construction outcomes. 展开更多
关键词 Underground engineering Rock mass discontinuity Orientation grouping Fisher distribution 3D point cloud Automated recognition
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Modeling Liquid Loading Behavior in Coalbed Methane Gathering Pipelines
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作者 Yonghong Deng Ming Yang +8 位作者 Liqiong Chen Hongwei Rao Shengguang Li Changhui Zhou Yangyang Huang Zizheng Kong Xicheng Gao Chong Di Ting He 《Fluid Dynamics & Materials Processing》 2026年第2期158-178,共21页
With the maturation of coalbed methane(CBM)exploitation and the transition into the late stages of dewatering and gas production,liquid loading in gathering pipelines has emerged as a major constraint on productivity ... With the maturation of coalbed methane(CBM)exploitation and the transition into the late stages of dewatering and gas production,liquid loading in gathering pipelines has emerged as a major constraint on productivity and operational stability.Based on real-time field data and gas-liquid physicochemical analyses,this study elucidates the mechanisms governing liquid loading formation under varying temperature,pressure,and water saturation conditions.An HYSYS model is employed to determine the water dew point,while the Turner model is used to evaluate the critical conditions for liquid holdup.The results indicate that gas water saturation exerts the dominant influence on liquid loading risk,followed by pressure,whereas temperature plays a comparatively minor role.When water saturation exceeds 2%and the operating temperature falls below the dew point,condensation-driven liquid loading increases sharply.To further characterize the spatial distribution of liquid accumulation,a steady-state OLGA model of a DN100 gathering pipeline network is developed to examine the effects of pipe diameter,water saturation,and soil temperature.The simulations show that larger pipe diameters and higher water saturation significantly aggravate liquid holdup,while elevated soil temperature mitigates liquid accumulation.Moreover,the liquid holdup ratio is found to correlate closely with flow regime transitions,confirming its suitability as a key indicator of liquid loading risk.Based on these findings,optimization strategies for pipeline design and operation are proposed.To mitigate liquid loading,the gathering pipeline velocity should be maintained above the critical value of 1.63 m/s,and the gas water content should be strictly controlled below 2%.Under operating conditions representative of the Hancheng block,it is recommended to reduce the pipeline diameter from DN130 to DN100 to enhance self-cleaning capacity.In addition,thermal insulation should be applied during winter operation to maintain the pipe wall temperature above 10◦C,thereby suppressing condensation-induced liquid accumulation. 展开更多
关键词 Coalbed methane gathering pipeline network liquid loading mechanism water dew point OLGA numerical simulation
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An enhanced segmentation method for 3D point cloud of tunnel support system using PointNet++t and coverage-voted strategy algorithms
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作者 Wenju Liu Fuqiang Gao +4 位作者 Shuangyong Dong Xiaoqing Wang Shuwen Cao Wanjie Wang Xiaomin Liu 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1653-1660,共8页
3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with m... 3D laser scanning technology is widely used in underground openings for high-precision,rapid,and nondestructive structural evaluations.Segmenting large 3D point cloud datasets,particularly in coal mine roadways with multi-scale targets,remains challenging.This paper proposes an enhanced segmentation method integrating improved PointNet++with a coverage-voted strategy.The coverage-voted strategy reduces data while preserving multi-scale target topology.The segmentation is achieved using an enhanced PointNet++algorithm with a normalization preprocessing head,resulting in a 94%accuracy for common supporting components.Ablation experiments show that the preprocessing head and coverage strategies increase segmentation accuracy by 20%and 2%,respectively,and improve Intersection over Union(IoU)for bearing plate segmentation by 58%and 20%.The accuracy of the current pretraining segmentation model may be affected by variations in surface support components,but it can be readily enhanced through re-optimization with additional labeled point cloud data.This proposed method,combined with a previously developed machine learning model that links rock bolt load and the deformation field of its bearing plate,provides a robust technique for simultaneously measuring the load of multiple rock bolts in a single laser scan. 展开更多
关键词 Point cloud segmentation Improved PointNet++ Tunnel laser scanning Rock bolt automatic recognition
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Comparison of binocular vision indices in Parkinson’s disease patients vs age-sex-matched healthy controls
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作者 Reyhaneh Shariati-Moghaddam Ali Shoeibi +6 位作者 Morad Amir Ahmad Hadi Ostadimoghaddam Hassan Hashemi Akbar Derakhshan Zahra Hemmatian Abbasali Yekta Mehdi Khabazkhoob 《International Journal of Ophthalmology(English edition)》 2026年第3期549-555,共7页
AIM:To evaluate the differences in near point of convergence(NPC),fusional vergence,saccadic eye movements,versional eye movements,and heterophoria between patients diagnosed with Parkinson’s disease(PD)and healthy s... AIM:To evaluate the differences in near point of convergence(NPC),fusional vergence,saccadic eye movements,versional eye movements,and heterophoria between patients diagnosed with Parkinson’s disease(PD)and healthy subjects.METHODS:A cross-sectional comparative study was conducted,enrolling two cohorts:a PD group and a healthy control group.The PD group was recruited via non-random convenience sampling,while the control group was selected randomly from individuals without PD.All participants were screened according to predefined inclusion and exclusion criteria before undergoing a comprehensive optometric assessment,which included measurements of uncorrected visual acuity,corrected visual acuity,and objective and subjective refraction.Subsequently,binocular vision function evaluations were performed,covering NPC measurement,fusional vergence reserve assessment at both distance and near,saccadic eye movement testing,and versional eye movement and heterophoria assessment.RESULTS:A total of 42 PD patients and 41 healthy controls were included in the final analysis.The two groups were well-matched in terms of sex distribution[29 males(69.0%)in the PD group vs 29 males(70.7%)in the control group,P=0.867]and mean age(55.3±9.6y in the PD group vs 54.9±9.8y in the control group,P=0.866).The prevalence of abnormal versional eye movements was significantly higher in the PD group than in the control group(23.81%,95%CI:12.05%-39.45%vs 7.32%,95%CI:1.54%-19.92%;P=0.025).Near exophoria was more prevalent in PD patients(61.90%,95%CI:45.64%-76.43%)than in controls(17.07%,95%CI:7.15%-32.06%),with a significant difference[odds ratio(OR)=7.99;95%CI:2.83-21.99;P<0.001].The mean NPC was significantly greater(more receded)in the PD group than in the control group(9.01±3.74 cm vs 7.20±2.15 cm;P=0.007).A statistically significant positive correlation was observed between PD severity and NPC values(Pearson’s correlation coefficient=0.309;P=0.046).Except for distance baseout break and distance base-out recovery values,all other fusional vergence parameters were significantly lower in the PD group than in the control group(P<0.05).The mean saccadic test score was significantly lower in PD patients than in controls(3.29±0.57 vs 3.78±0.42;P<0.001).Among all fusional vergence indices,near base-in blur yielded the highest area under the curve(AUC=0.877),with a sensitivity of 69%and specificity of 90%,followed by distance base-out blur(AUC=0.824,sensitivity=97.6%,specificity=66.7%),near base-out blur(AUC=0.814,sensitivity=76.2%,specificity=72.7%),near base-out break(AUC=0.749,sensitivity=78.6%,specificity=67.6%),and near base-out recovery(AUC=0.749,sensitivity=95.2%,specificity=50%).CONCLUSION:PD is associated with significant binocular vision function impairment,with receded NPC and reduced near fusional vergence reserves being the most prominent disorders.These findings highlight the potential value of binocular vision assessment as a non-invasive biomarker for the early detection and clinical monitoring of PD. 展开更多
关键词 Parkinson’s disease binocular vision near point of convergence fusional vergence saccadic eye movement HETEROPHORIA
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Transformer-Driven Multimodal for Human-Object Detection and Recognition for Intelligent Robotic Surveillance
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作者 Aman Aman Ullah Yanfeng Wu +3 位作者 Shaheryar Najam Nouf Abdullah Almujally Ahmad Jalal Hui Liu 《Computers, Materials & Continua》 2026年第4期1364-1383,共20页
Human object detection and recognition is essential for elderly monitoring and assisted living however,models relying solely on pose or scene context often struggle in cluttered or visually ambiguous settings.To addre... Human object detection and recognition is essential for elderly monitoring and assisted living however,models relying solely on pose or scene context often struggle in cluttered or visually ambiguous settings.To address this,we present SCENET-3D,a transformer-drivenmultimodal framework that unifies human-centric skeleton features with scene-object semantics for intelligent robotic vision through a three-stage pipeline.In the first stage,scene analysis,rich geometric and texture descriptors are extracted from RGB frames,including surface-normal histograms,angles between neighboring normals,Zernike moments,directional standard deviation,and Gabor-filter responses.In the second stage,scene-object analysis,non-human objects are segmented and represented using local feature descriptors and complementary surface-normal information.In the third stage,human-pose estimation,silhouettes are processed through an enhanced MoveNet to obtain 2D anatomical keypoints,which are fused with depth information and converted into RGB-based point clouds to construct pseudo-3D skeletons.Features from all three stages are fused and fed in a transformer encoder with multi-head attention to resolve visually similar activities.Experiments on UCLA(95.8%),ETRI-Activity3D(89.4%),andCAD-120(91.2%)demonstrate that combining pseudo-3D skeletonswith rich scene-object fusion significantly improves generalizable activity recognition,enabling safer elderly care,natural human–robot interaction,and robust context-aware robotic perception in real-world environments. 展开更多
关键词 Human object detection elderly care RGB-based pose estimation scene context analysis object recognition Gabor features point cloud reconstruction
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Point-of-care antigen detection for porcine deltacoronavirus:Colloidal gold and fluorescent immunochromatographic test strips
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作者 Zezhao Cao Junchao Shi +9 位作者 Ruijie Hu Jun Xue Gaili Wang Zi Li Huabo Yu Wei Liu Wenqi He Hualei Wang Haili Zhang Yungang Lan 《Journal of Integrative Agriculture》 2026年第1期394-397,共4页
Highlights By conjugating the same anti-N monoclonal antibody(mAb4-mAb1)with colloidal gold or fluorescent microspheres,this study developed two rapid point-of-care antigen immunochromatographic strips for the detecti... Highlights By conjugating the same anti-N monoclonal antibody(mAb4-mAb1)with colloidal gold or fluorescent microspheres,this study developed two rapid point-of-care antigen immunochromatographic strips for the detection of porcine deltacoronavirus.The fluorescent microsphere-based lateral flow test strip demonstrated a sensitivity of 10^(1.7)TCID_(50)/0.1 mL,which is fourfold higher than that of the colloidal gold-based assay.Porcine deltacoronavirus(PDCoV)is a recently identified enteric coronavirus that causes an acute infectious disease in piglets,leading to diarrhea,vomiting,dehydration,and mortality(Hu et al.2015). 展开更多
关键词 enteric coronavirus point care antigen detection fluorescent microspheresthis immunochromatographic strips porcine deltacoronavirusthe fluorescent immunochromatographic test strips colloidal gold porcine deltacoronavirus
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Kibble–Zurek Meets Tricriticality:Breakdown of Adiabatic-Impulse and New Scaling Forms
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作者 Chengshu Li 《Chinese Physics Letters》 2026年第1期1-2,共2页
The Kibble-Zurek (KZ) effect offers an overarching description of dynamical scaling behavior near a critical point.[1,2] Originally proposed in a classical setup,the KZ effect has been generalized to quantum phase tra... The Kibble-Zurek (KZ) effect offers an overarching description of dynamical scaling behavior near a critical point.[1,2] Originally proposed in a classical setup,the KZ effect has been generalized to quantum phase transitions[3-5] and is actively explored on quantum simulation platforms.[6-9] Exploring how the KZ effect fares across different criticalities has proven to be a rewarding pursuit,significantly enriching our understanding of nonequilibrium quantum dynamics.[3-5,10-23] 展开更多
关键词 quantum phase transitions dynamical scaling behavior kz effect kibble zurek effect tricriticality quantum simulation platforms nonequilibrium quantum dynamics critical point
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