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Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South China 被引量:1
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作者 FANG Chaogang ZHANG Chengcheng +5 位作者 MENG Guixi XU Jinlong XU Naicen LI Hualing LIU Mu LIU Bo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第1期150-167,共18页
The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic m... The Late Permian was marked by a series of important geological events and widespread organic-rich black shale depositions,acting as important unconventional hydrocarbon source rocks.However,the mechanism of organic matter(OM)enrichment throughout this period is still controversial.Based on geochemical data,the marine redox conditions,paleogeographic and hydrographic environment,primary productivity,volcanism,and terrigenous input during the Late Permian in the Lower Yangtze region have been studied from the Putaoling section,Chaohu,to provide new insights into OM accumulation.Five Phases are distinguished based on the TOC and environmental variations.In Phase I,anoxic conditions driven by water restriction enhanced OM preservation.In Phase II,euxinic and cycling hydrological environments were the two most substantial controlling factors for the massive OM deposition.During Phase III,intensified terrestrial input potentially diluted the OM in sediment and the presence of oxygen in bottom water weakened the preservation condition.Phase IV was characterized by a relatively higher abundance of mercury(Hg)and TOC(peak at 16.98 wt%),indicating that enhanced volcanism potentially stimulated higher productivity and a euxinic environment.In Phase V,extremely lean OM was preserved as a result of terrestrial dilutions and decreasing primary productivity.Phases I,II and IV are characterized as the most prominent OM-rich zones due to the effective interactions of the controlling factors,namely paleogeographic,hydrographic environment,volcanism,and redox conditions. 展开更多
关键词 GEOCHEMISTRY redox condition primary productivity OM accumulation Lopingian/Changhsingian lower Yangtze region
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Early-diverging Titanosauriform(Dinosauria,Sauropoda)Teeth from the Lower Cretaceous Yixian Formation of Southeastern Inner Mongolia,Northeast China
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作者 ZHANG Honggang YIN Yalei +1 位作者 PEI Rui ZHOU Changfu 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第2期303-310,共8页
Three eusauropod teeth(SDUST-V1064,PMOL-AD00176,PMOL-ADt0005)are reported from the Lower Cretaceous Yixian Formation of Ningcheng,southeastern Inner Mongolia,China.Two of them(SDUST-V1064,PMOL-AD00176)are assigned to ... Three eusauropod teeth(SDUST-V1064,PMOL-AD00176,PMOL-ADt0005)are reported from the Lower Cretaceous Yixian Formation of Ningcheng,southeastern Inner Mongolia,China.Two of them(SDUST-V1064,PMOL-AD00176)are assigned to early-diverging titanosauriforms in having slightly mesiodistal expansion at the base of the tooth crown,a slenderness index value>2.0 and<4.0,and D-shaped cross section.Furthermore,SDUST-V1064 and PMOL-AD00176 are referred as an Euhelopus-like titanosauriform on the basis of having a sub-circular boss on the lingual surface and an asymmetrical crown-root margin which slants apically,respectively.CT scan data of SDUST-V1064 reveals new dental information of early-diverging titanosauriforms,for example,the enamel on the labial side thicker than that on the lingual side,an enamel/dentine ratio of 0.26 and a boss present on the lingual side of the dentine of the crown. 展开更多
关键词 teeth TITANOSAURIFORMES lower Cretaceous Yixian Formation Ningcheng
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Surface and Deep Structure of the Hanshan-Wuwei Basins in the Lower Yangtze Region:Implications for Mesozoic Tectonic Evolution of the South China Block
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作者 KAN Tianxiang LI Longming +3 位作者 ZHENG Hongjun LI Jiahao ZHAO Xilin CHEN Mo 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2024年第5期1154-1170,共17页
Indicating the tectonic features of the Hanshan-Wuwei basin can reconstruct the framework of the basins formed in Mesozoic and further understand the Mesozoic tectonic evolution of the South China Block.Studies on sur... Indicating the tectonic features of the Hanshan-Wuwei basin can reconstruct the framework of the basins formed in Mesozoic and further understand the Mesozoic tectonic evolution of the South China Block.Studies on surface structure,regional stress field and deep geophysical characteristics of the Mesozoic Hanshan-Wuwei basin in Lower Yangtze region were carried out.NE-NNE trending folds and faults developed in the northern margin of the basins.The reconstruction of tectonic stress fields indicates four stress stages dominating the basins'evolution including NW-SE compression,N-S compression,NW-SE extension and NWW-SEE compression.2D seismic profiles reveal coexistence of thrust,strike-slip and normal faults in the basin.Combined with regional geological studies,the geodynamic processes for the formation of the Hanshan-Wuwei basin can be divided into five stages:1)During the Late Triassic,EW trending foreland basin was formed by N-S compression;2)From Mid-Jurassic to Late Jurassic,continuous compression strengthened the foreland deformation and formed thrust nappes.In this stage,the integrated foreland basin was compartmentalized or fragmented,and transferred to the broken foreland basin;3)NE-trending sinistral strike-slip movement at the beginning of the Early Cretaceous;4)Regional extension resulted in normal faults and rift basins developing in the Late Cretaceous;5)The NWW-SEE compression at the end of the Late Cretaceous caused NW sinistral strike-slip faults to form,which partly transformed the rift basin. 展开更多
关键词 structure seismic profile MESOZOIC Hanshan-Wuwei basins lower Yangtze region
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Neural Network Robust Control Based on Computed Torque for Lower Limb Exoskeleton
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作者 Yibo Han Hongtao Ma +6 位作者 Yapeng Wang Di Shi Yanggang Feng Xianzhong Li Yanjun Shi Xilun Ding Wuxiang Zhang 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期83-99,共17页
The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial settings.Complex modeling errors of the exoskeleton in different application scenarios pose challenges to the ... The lower limb exoskeletons are used to assist wearers in various scenarios such as medical and industrial settings.Complex modeling errors of the exoskeleton in different application scenarios pose challenges to the robustness and stability of its control algorithm.The Radial Basis Function(RBF)neural network is used widely to compensate for modeling errors.In order to solve the problem that the current RBF neural network controllers cannot guarantee the asymptotic stability,a neural network robust control algorithm based on computed torque method is proposed in this paper,focusing on trajectory tracking.It innovatively incorporates the robust adaptive term while introducing the RBF neural network term,improving the compensation ability for modeling errors.The stability of the algorithm is proved by Lyapunov method,and the effectiveness of the robust adaptive term is verified by the simulation.Experiments wearing the exoskeleton under different walking speeds and scenarios were carried out,and the results show that the absolute value of tracking errors of the hip and knee joints of the exoskeleton are consistently less than 1.5°and 2.5°,respectively.The proposed control algorithm effectively compensates for modeling errors and exhibits high robustness. 展开更多
关键词 lower limb exoskeleton Model compensation RBF neural network Computed torque method
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Establishing the relationship between land use land cover,normalized difference vegetation index and land surface temperature:A case of Lower Son River Basin,India
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作者 Shipra Singh Pankaj Kumar +2 位作者 Rakhi Parijat Barbaros Gonengcil Abhinav Rai 《Geography and Sustainability》 CSCD 2024年第2期265-275,共11页
The study explores the intricate interplay between land use land cover(LULC),normalized difference vegetation index(NDVI),and land surface temperature(LST)within the Lower Son River Basin in India from 1991 to 2020.Th... The study explores the intricate interplay between land use land cover(LULC),normalized difference vegetation index(NDVI),and land surface temperature(LST)within the Lower Son River Basin in India from 1991 to 2020.The region’s ecological balance has been increasingly strained due to rapid urbanization and changing land use patterns.Through a combination of Landsat TM&OLI/TIRS satellite imageries and geospatial analysis techniques,this study unveils the intricate connection between land use and land cover changes,vegetation,and land surface temperature variations.The study area is classified into three altitudinal zones(Zone Ⅰ:39–300 m,Zone Ⅱ:301–600 m and Zone Ⅲ:601–1,247 m)to examine the changes in depth.The area has seen significant changes in LULC,vegetation and LST in all the three altitudinal zones.The findings hold significant implications for sustainable land management and environmental conservation strategies in the Lower Son River Basin.As per the result,103,438 ha of vegetation was converted into agriculture land and 82,572 ha of agricultural land was transformed into settlements from 1991 to 2020.This trend shows human pressure on the land resource in the study area.Minor increase in water body is seen which is attributed to commissioning of Bansagar dam.Zone Ⅰ has seen highest settlement growth while Zone Ⅲ experienced severe deforestation of around 15%.Zone Ⅱ and Ⅲ needs attention for holistic sustenance.Analysis of LST shows that it has increased by 0.82℃ from 1991 to 2020 which is a red flag.The study underscores the critical importance of balanced land use practices to preserve ecological integrity and mitigate the adverse effects of urbanization and climate change. 展开更多
关键词 lower Son River Basin LULC LST NDVI Correlation
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Model Parameters Identification and Backstepping Control of Lower Limb Exoskeleton Based on Enhanced Whale Algorithm
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作者 Yan Shi Jiange Kou +2 位作者 Zhenlei Chen Yixuan Wang Qing Guo 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第2期100-114,共15页
Exoskeletons generally require accurate dynamic models to design the model-based controller conveniently under the human-robot interaction condition.However,due to unknown model parameters such as the mass,moment of i... Exoskeletons generally require accurate dynamic models to design the model-based controller conveniently under the human-robot interaction condition.However,due to unknown model parameters such as the mass,moment of inertia and mechanical size,the dynamic model of exoskeletons is difficult to construct.Hence,an enhanced whale optimization algorithm(EWOA)is proposed to identify the exoskeleton model parameters.Meanwhile,the periodic excitation trajectories are designed by finite Fourier series to input the desired position demand of exoskeletons with mechanical physical constraints.Then a backstepping controller based on the identified model is adopted to improve the human-robot wearable comfortable performance under cooperative motion.Finally,the proposed Model parameters identification and control are verified by a two-DOF exoskeletons platform.The knee joint motion achieves a steady-state response after 0.5 s.Meanwhile,the position error of hip joint response is less than 0.03 rad after 0.9 s.In addition,the steady-state human-robot interaction torque of the two joints is constrained within 15 N·m.This research proposes a whale optimization algorithm to optimize the excitation trajectory and identify model parameters.Furthermore,an enhanced mutation strategy is adopted to avoid whale evolution’s unsatisfactory local optimal value. 展开更多
关键词 Parameter identification Enhanced whale optimization algorithm(EWOA) BACKSTEPPING Human-robot interaction lower limb exoskeleton
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Main controlling factor and mechanism of gas-in-place content of the Lower Cambrian shale from different sedimentary facies in the western Hubei area, South China
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作者 Gang Li Xian-Ming Xiao +3 位作者 Bo-Wei Cheng Chen-Gang Lu Yue Feng Dong-Sheng Li 《Petroleum Science》 SCIE EI CAS CSCD 2024年第3期1488-1507,共20页
The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not w... The Lower Cambrian shale gas in the western Hubei area,South China has a great resource prospect,but the gas-in-place(GIP)content in different sedimentary facies varies widely,and the relevant mechanism has been not well understood.In the present study,two sets of the Lower Cambrian shale samples from the Wells YD4 and YD5 in the western Hubei area,representing the deep-water shelf facies and shallowwater platform facies,respectively,were investigated on the differences of pore types,pore structure and methane adsorption capacity between them,and the main controlling factor and mechanism of their methane adsorption capacities and GIP contents were discussed.The results show that the organic matter(OM)pores in the YD4 shale samples are dominant,while the inorganic mineral(IM)pores in the YD5 shale samples are primary,with underdeveloped OM pores.The pore specific surface area(SSA)and pore volume(PV)of the YD4 shale samples are mainly from micropores and mesopores,respectively,while those of the YD5 shale samples are mainly from micropores and macropores,respectively.The methane adsorption capacity of the YD4 shale samples is significantly higher than that of the YD5 shale samples,with a maximum absolute adsorption capacity of 3.13 cm^(3)/g and 1.31 cm^(3)/g in average,respectively.Compared with the shallow-water platform shale,the deep-water shelf shale has a higher TOC content,a better kerogen type and more developed OM pores,which is the main mechanism for its higher adsorption capacity.The GIP content models based on two samples with a similar TOC content selected respectively from the Wells YD4 and YD5 further indicate that the GIP content of the deep-water shelf shale is mainly 34 m^(3)/t within a depth range of 1000—4000 m,with shale gas exploration and development potential,while the shallow-water platform shale has normally a GIP content of<1 m^(3)/t,with little shale gas potential.Considering the geological and geochemical conditions of shale gas formation and preservation,the deep-water shelf facies is the most favorable target for the Lower Cambrian shale gas exploration and development in the western Hubei area,South China. 展开更多
关键词 lower Cambrian shale Deep-water shelf facies Shallow-waterplat form facies Pore structure Methane adsorption Gas-in-place content Controlling factor
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Kinematics ofmandibular advancement devices(MADs):Why do some MADs move the lower jaw backward duringmouth opening?
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作者 Juan A.Cabrera Alex Bataller +1 位作者 Sergio Postigo Marcos García 《Bio-Design and Manufacturing》 SCIE EI CAS CSCD 2024年第5期637-650,共14页
Mandibular advancement devices(MADs)are widely used treatments for obstructive sleep apnea.MADs function by advancing the lower jaw to open the upper airway.To increase patient comfort,most patients allow the mouth to... Mandibular advancement devices(MADs)are widely used treatments for obstructive sleep apnea.MADs function by advancing the lower jaw to open the upper airway.To increase patient comfort,most patients allow the mouth to be opened.However,not all systems maintain the lower jaw in a forward position during mouth opening,which results in the production of a retrusion that favors the collapse of the upper airway.Furthermore,the kinematic behavior of the mechanism formed by the mandible-device assembly depends on jaw morphology.This means that,during mouth opening,some devices cause lower jaw protrusion in some patients,but cause its retraction in others.In this study,we report the behavior of well-known devices currently on themarket.To do so,we developed a kinematic model of the lower jawdevice assembly.Thismodelwas validated for all devices analyzed using a high-resolution camera system.Our results show that some of the devices analyzed here did not produce the correct behavior during patient mouth opening. 展开更多
关键词 Mandibular advancement devices lower jaw kinematics Sleep apnea
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Lower synaptic density and its association with cognitive dysfunction in patients with obsessive-compulsive disorder
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作者 Qian Xiao Jiale Hou +4 位作者 Ling Xiao Ming Zhou Zhiyou He Huixi Dong Shuo Hu 《General Psychiatry》 CSCD 2024年第3期422-430,共9页
Background Understanding synaptic alteration in obsessive-compulsive disorder(OCD)is crucial for elucidating its pathological mechanisms,but in vivo research on this topic remains limited.Aims This study aimed to iden... Background Understanding synaptic alteration in obsessive-compulsive disorder(OCD)is crucial for elucidating its pathological mechanisms,but in vivo research on this topic remains limited.Aims This study aimed to identify the synaptic density indicators in OCD and explore the relationship between cognitive dysfunction and synaptic density changes in OCD.Methods This study enrolled 28 drug-naive adults with OCD aged 18-40 years and 16 healthy controls(HCs).Three-dimensional T1-weighted structural magnetic resonance imaging and 18F-SynVesT-1 positron emission tomography were conducted.Cognitive function was assessed using the Wisconsin Cart Sorting Test(WCST)in patients with OCD and HCs.Correlative analysis was performed to examine the association between synaptic density reduction and cognitive dysfunction.Results Compared with HCs,patients with OCD showed reduced synaptic density in regions of the cortico-striatothalamo-cortical circuit such as the bilateral putamen,left caudate,left parahippocampal gyrus,left insula,left parahippocampal gyrus and left middle occipital lobe(voxel p<0.001,uncorrected,with cluster level above 50 contiguous voxels).The per cent conceptual-level responses of WCST were positively associated with the synaptic density reduction in the left middle occipital gyrus(R^(2)=0.1690,p=0.030),left parahippocampal gyrus(R^(2)=0.1464,p=0.045)and left putamen(R^(2)=0.1967,p=0.018)in patients with OCD.Conclusions Adults with OCD demonstrated lower 18Flabelled difluoro analogue of 18F-SynVesT-1 compared with HCs,indicating potentially lower synaptic density.This is the first study to explore the synaptic density in patients with OCD and provides insights into potential biological targets for cognitive dysfunctions in OCD. 展开更多
关键词 PATIENTS DYSFUNCTION lower
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Monitoring and evaluation of the water quality of the Lower Neches River, Texas, USA
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作者 Qin Qian Mengjie He +1 位作者 Frank Sun Xinyu Liu 《Water Science and Engineering》 EI CAS CSCD 2024年第1期21-32,共12页
Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collec... Increasing bacteria levels in the Lower Neches River caused by Hurricane Harvey has been of a serious concern.This study is to analyze the historical water sampling measurements and real-time water quality data collected with wireless sensors to monitor and evaluate water quality under different hydrological and hydraulic conditions.The statistical and Pearson correlation analysis on historical water samples determines that alkalinity,chloride,hardness,conductivity,and pH are highly correlated,and they decrease with increasing flow rate due to dilution.The flow rate has positive correlations with Escherichia coli,total suspended solids,and turbidity,which demonstrates that runoff is one of the causes of the elevated bacteria and sediment loadings in the river.The correlation between E.coli and turbidity indicates that turbidity greater than 45 nephelometric turbidity units in the Neches River can serve as a proxy for E.coli to indicate the bacterial outbreak.A series of statistical tools and an innovative two-layer data smoothing filter are developed to detect outliers,fill missing values,and filter spikes of the sensor measurements.The correlation analysis on the sensor data illustrates that the elevated sediment/bacteria/algae in the river is either caused by the first flush rain and heavy rain events in December to March or practices of land use and land cover.Therefore,utilizing sensor measurements along with rainfall and discharge data is recommended to monitor and evaluate water quality,then in turn to provide early alerts on water resources management decisions. 展开更多
关键词 Water quality Pearson correlation analysis lower Neches River YSI wireless sensors Non-point pollution
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Hydrocarbon accumulation history in Lower Cretaceous in northern slope of Bongor Basin in Chad,Central Africa
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作者 WANG Li NIE Zhiquan +5 位作者 DU Yebo WANG Lin MENG Fanchao CHEN Yuliu HU Jie DING Ruxin 《Petroleum Exploration and Development》 SCIE 2024年第1期141-151,共11页
Based on the analysis of the fluid inclusion homogenization temperature and apatite fission track on the northern slope zone of the Bongor Basin in Chad,this paper studied the time and stages of hydrocarbon accumulati... Based on the analysis of the fluid inclusion homogenization temperature and apatite fission track on the northern slope zone of the Bongor Basin in Chad,this paper studied the time and stages of hydrocarbon accumulation in the study area.The results show that:(1)The brine inclusions of the samples from the Kubla and Prosopis formations in the Lower Cretaceous coexisting with the hydrocarbon generally present two sets of peak ranges of homogenization temperature,with the peak ranges of low temperature and high temperature being 75–105℃ and 115–135℃,respectively;(2)The samples from the Kubla and Prosopis formations have experienced five tectonic evolution stages,i.e.,rapid subsidence in the Early Cretaceous,tectonic inversion in the Late Cretaceous,small subsidence in the Paleogene,uplift at the turn of the Paleogene and Neogene,and subsidence since the Miocene,in which the denudation thickness of the Late Cretaceous and after the turn of the Paleogene and Neogene are~1.8 km and~0.5 km,respectively.The cumulative denudation thickness of the two periods is about 2.3 km;(3)Using the brine inclusion homogenization temperature coexisting with the hydrocarbon as the capture temperature of the hydrocarbon,and combining with the apatite fission track thermal history modeling,the result shows that the Kubla and Prosopis formations in the Lower Cretaceous on the northern slope of the Bongor Basin have the same hydrocarbon accumulation time and stages,both of which have undergone two stages of hydrocarbon charging at 80–95 Ma and 65–80 Ma.The first stage of charging corresponds to the initial migration of hydrocarbon at the end of the Early Cretaceous rapid sedimentation,while the second stage of charging is in the stage of intense tectonic inversion in the Late Cretaceous. 展开更多
关键词 Central Africa CHAD Bongor Basin lower Cretaceous hydrocarbon accumulation stages fluid inclusions apatite fission track
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Protocol for lower back pain management: Insights from the French healthcare system
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作者 Lea Evangeline Boyer Mathieu Boudier-Revéret Min Cheol Chang 《World Journal of Clinical Cases》 SCIE 2024年第11期1875-1880,共6页
In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with ... In this editorial we comment on the article published in a recent issue of the World Journal of Clinical Cases.This article described a novel ultrasound-guided lateral recess block approach in treating a patient with lateral recess stenosis.The impact of spinal pain-related disability extends significantly,causing substantial human suffering and medical costs.Each county has its preferred treatment strategies for spinal pain.Here,we explore the lower back pain(LBP)treatment algorithm recommended in France.The treatment algorithm for LBP recommended by the French National Authority for Health emphasizes early patient activity and minimal medication use.It encourages the continuation of daily activities,limits excessive medication and spinal injections,and incorporates psychological assessments and non-pharmacological therapies for chronic cases.However,the algorithm may not aggressively address acute pain in the early stages,potentially delaying relief and increasing the risk of chronicity.Additionally,the recommended infiltrations primarily involve caudal epidural steroid injections,with limited consideration for other injection procedures,such as transforaminal or interlaminar epidural steroid injections.The fixed follow-up timeline may not accommodate patients who do not respond to initial treatment or experience intense pain,potentially delaying the exploration of alternative therapies.Despite these limitations,understanding the strengths and weaknesses of the French approach could inform adaptations in LBP treatment strategies globally,potentially enhancing patient outcomes and satisfaction across diverse healthcare systems. 展开更多
关键词 lower back pain PROTOCOL FRANCE TREATMENT Chronic pain
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Th17/Treg balance and macrophage polarization ratio in lower extremity arteriosclerosis obliterans
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作者 Zhen-Zhen Li Min Liu +5 位作者 Xiong-Hui He Zhen-Dong Liu Zhan-Xiang Xiao Hao Qian You-Fei Qi Cun-Chuan Wang 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2024年第3期127-136,I0006-I0009,共14页
Objective:To explore the balance of peripheral blood T helper 17 cells/regulatory T cell(Th17/Treg)ratio and the polarization ratio of M1 and M2 macrophages in lower extremity arteriosclerosis obliterans(ASO).Methods:... Objective:To explore the balance of peripheral blood T helper 17 cells/regulatory T cell(Th17/Treg)ratio and the polarization ratio of M1 and M2 macrophages in lower extremity arteriosclerosis obliterans(ASO).Methods:A rat model of lower extremity ASO was established,and blood samples from patients with lower extremity ASO before and after surgery were obtained.ELISA was used to detect interleukin 6(IL-6),IL-10,and IL-17.Real-time RCR and Western blot analyses were used to detect Foxp3,IL-6,IL-10,and IL-17 expression.Moreover,flow cytometry was applied to detect the Th17/Treg ratio and M1/M2 ratio.Results:Compared with the control group,the iliac artery wall of ASO rats showed significant hyperplasia,and the concentrations of cholesterol and triglyceride were significantly increased(P<0.01),indicating the successful establishment of ASO.Moreover,the levels of IL-6 and IL-17 in ASO rats were pronouncedly increased(P<0.05),while the IL-10 level was significantly decreased(P<0.05).In addition to increased IL-6 and IL-17 levels,the mRNA and protein levels of Foxp3 and IL-10 in ASO rats were significantly decreased compared with the control group.The Th17/Treg and M1/M2 ratios in the ASO group were markedly increased(P<0.05).These alternations were also observed in ASO patients.After endovascular surgery(such as percutaneous transluminal angioplasty and arterial stenting),all these changes were significantly improved(P<0.05).Conclusions:The Th17/Treg and M1/M2 ratios were significantly increased in ASO,and surgery can effectively improve the balance of Th17/Treg,and reduce the ratio of M1/M2,and the expression of inflammatory factors. 展开更多
关键词 lower extremity arteriosclerosis Regulatory T cells Regulatory B cells Inflammatory factors M1 macrophages M2 macrophages
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Personalized Lower Limb Gait Reconstruction Modeling Based on RFA-ProMP
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作者 Chunhong Zeng Kang Lu +1 位作者 Zhiqin He Qinmu Wu 《Computers, Materials & Continua》 SCIE EI 2024年第7期1441-1456,共16页
Personalized gait curves are generated to enhance patient adaptability to gait trajectories used for passive training in the early stage of rehabilitation for hemiplegic patients.The article utilizes the random forest... Personalized gait curves are generated to enhance patient adaptability to gait trajectories used for passive training in the early stage of rehabilitation for hemiplegic patients.The article utilizes the random forest algorithm to construct a gait parameter model,which maps the relationship between parameters such as height,weight,age,gender,and gait speed,achieving prediction of key points on the gait curve.To enhance prediction accuracy,an attention mechanism is introduced into the algorithm to focus more on the main features.Meanwhile,to ensure high similarity between the reconstructed gait curve and the normal one,probabilistic motion primitives(ProMP)are used to learn the probability distribution of normal gait data and construct a gait trajectorymodel.Finally,using the specified step speed as input,select a reference gait trajectory from the learned trajectory,and reconstruct the curve of the reference trajectoryusing the gait keypoints predictedby the parametermodel toobtain the final curve.Simulation results demonstrate that the method proposed in this paper achieves 98%and 96%curve correlations when generating personalized lower limb gait curves for different patients,respectively,indicating its suitability for such tasks. 展开更多
关键词 Personalized lower limb gait prediction random forest probabilistic movement primitives
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Enrichment model and major controlling factors of below-source tight oil in Lower Cretaceous Fuyu reservoirs in northern Songliao Basin,NE China
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作者 WANG Xiaojun BAI Xuefeng +9 位作者 LI Junhui JIN Zhijun WANG Guiwen CHEN Fangju ZHENG Qiang HOU Yanping YANG Qingjie LI Jie LI Junwen CAI Yu 《Petroleum Exploration and Development》 SCIE 2024年第2期279-291,共13页
Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics... Based on the geochemical,seismic,logging and drilling data,the Fuyu reservoirs of the Lower Cretaceous Quantou Formation in northern Songliao Basin are systematically studied in terms of the geological characteristics,the tight oil enrichment model and its major controlling factors.First,the Quantou Formation is overlaid by high-quality source rocks of the Upper Cretaceous Qingshankou Formation,with the development of nose structure around sag and the broad and continuous distribution of sand bodies.The reservoirs are tight on the whole.Second,the configuration of multiple elements,such as high-quality source rocks,reservoir rocks,fault,overpressure and structure,controls the tight oil enrichment in the Fuyu reservoirs.The source-reservoir combination controls the tight oil distribution pattern.The pressure difference between source and reservoir drives the charging of tight oil.The fault-sandbody transport system determines the migration and accumulation of oil and gas.The positive structure is the favorable place for tight oil enrichment,and the fault-horst zone is the key part of syncline area for tight oil exploration.Third,based on the source-reservoir relationship,transport mode,accumulation dynamics and other elements,three tight oil enrichment models are recognized in the Fuyu reservoirs:(1)vertical or lateral migration of hydrocarbon from source rocks to adjacent reservoir rocks,that is,driven by overpressure,hydrocarbon generated is migrated vertically or laterally to and accumulates in the adjacent reservoir rocks;(2)transport of hydrocarbon through faults between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downward through faults to the sandbodies that are separated from the source rocks;and(3)migration of hydrocarbon through faults and sandbodies between separated source and reservoirs,that is,driven by overpressure,hydrocarbon migrates downwards through faults to the reservoir rocks that are separated from the source rocks,and then migrates laterally through sandbodies.Fourth,the differences in oil source conditions,charging drive,fault distribution,sandbody and reservoir physical properties cause the differential enrichment of tight oil in the Fuyu reservoirs.Comprehensive analysis suggests that the Fuyu reservoir in the Qijia-Gulong Sag has good conditions for tight oil enrichment and has been less explored,and it is an important new zone for tight oil exploration in the future. 展开更多
关键词 northern Songliao Basin Cretaceous Quantou Formation Qingshankou Formation upper generation and lower storage Fuyu reservoir tight oil main control factor enrichment model
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Influences of burial process on diagenesis and high-quality reservoir development of deep-ultra-deep clastic rocks:A case study of Lower Cretaceous Qingshuihe Formation in southern margin of Junggar Basin,NW China
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作者 CHEN Sirui XIAN Benzhong +4 位作者 JI Youliang LI Jiaqi TIAN Rongheng WANG Pengyu TANG Heyuan 《Petroleum Exploration and Development》 SCIE 2024年第2期364-379,共16页
Taking the Lower Cretaceous Qingshuihe Formation in the southern margin of Junggar Basin as an example,the influences of the burial process in a foreland basin on the diagenesis and the development of high-quality res... Taking the Lower Cretaceous Qingshuihe Formation in the southern margin of Junggar Basin as an example,the influences of the burial process in a foreland basin on the diagenesis and the development of high-quality reservoirs of deep and ultra-deep clastic rocks were investigated using thin section,scanning electron microscope,electron probe,stable isotopic composition and fluid inclusion data.The Qingshuihe Formation went through four burial stages of slow shallow burial,tectonic uplift,progressive deep burial and rapid deep burial successively.The stages of slow shallow burial and tectonic uplift not only can alleviate the mechanical compaction of grains,but also can maintain an open diagenetic system in the reservoirs for a long time,which promotes the dissolution of soluble components by meteoric freshwater and inhibits the precipitation of dissolution products in the reservoirs.The late rapid deep burial process contributed to the development of fluid overpressure,which effectively inhibits the destruction of primary pores by compaction and cementation.The fluid overpressure promotes the development of microfractures in the reservoir,which enhances the dissolution effect of organic acids.Based on the quantitative reconstruction of porosity evolution history,it is found that the long-term slow shallow burial and tectonic uplift processes make the greatest contribution to the development of deep-ultra-deep high-quality clastic rock reservoirs,followed by the late rapid deep burial process,and the progressive deep burial process has little contribution. 展开更多
关键词 deep-ultra-deep layer clastic rock reservoir DIAGENESIS burial process lower Cretaceous Qingshuihe Formation southern margin of Junggar Basin
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Lower Extremity Arterial Disease in Patients with Type 2 Diabetes: Prevalence and Associated Factors at the Libreville University Hospital Center
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作者 Allognon Mahutondji Christian Ayo Bivigou Elsa +13 位作者 Ntoutoume Mvé Dylan Anthony N’nang Jean-Fidel Kinga Armel Mpori Jamila Myrtille Akagah Kondé Christelle Ndoume Obiang Francis Yékini Carole Fadylath Ndjibah Alakoua Cajole Ludvine Babongui Boussougou Latifah Mipinda Jean-Bruno Moubamba Franck Ecke Nzengue Jean-Emmanuel Houenassi Dèdonougbo Martin Boguikouma Jean-Bruno 《World Journal of Cardiovascular Diseases》 CAS 2024年第5期295-308,共14页
Introduction: Lower extremity arterial disease in diabetic patients has distinct characteristics. Objectives: To study the hospital frequency of lower extremity arterial disease and identify associated factors in diab... Introduction: Lower extremity arterial disease in diabetic patients has distinct characteristics. Objectives: To study the hospital frequency of lower extremity arterial disease and identify associated factors in diabetic patients at the Libreville University Hospital Center (CHUL). Materials and Methods: This was a cross-sectional study conducted from July 1, 2023, to January 31, 2024, in the endocrinology department of the CHUL. All patients with type 2 diabetes over the age of 18 admitted to this department, regardless of the reason for hospitalization, who provided informed consent, were included. Socio-demographic data and cardiovascular risk factors were recorded. Personal and family cardiovascular history and functional symptoms were investigated. The physical examination included measuring blood pressure, heart rate, and the ankle-brachial index in all patients. Results: A total of 219 patients were included, of whom 75 had lower extremity arterial disease, representing a prevalence of 34.24%. It was compensated in 28 cases (37.33%) and decompensated in 39 patients (52%). In eight cases (10.67%), there was critical chronic ischemia. Cardiovascular risk factors associated with diabetes were physical inactivity (89.5%), hypertension (55.25%), overweight (49.77%), obesity (22.84%), and smoking (10.04%). In multivariate analysis, only hypertension (OR = 2.09;95% CI: 1.05 - 4.17;p = 0.035) and LDL cholesterol (OR = 2.75;95% CI: 1.10 - 6.85;p = 0.03) were significantly associated with lower extremity arterial disease in diabetics at the University Hospital of Libreville. Conclusion: Lower extremity arterial disease is common in diabetic patients at the University Hospital of Libreville. It is often asymptomatic, thus requiring systematic screening.[-rId11-] 展开更多
关键词 lower Extremity Arterial Disease DIABETES HYPERTENSION Ankle-Brachial Index GABON
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The dawn−dusk asymmetry in mesosphere and lower thermosphere temperature disturbances during geomagnetic storms at high latitude
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作者 GuanChun Wei JianYong Lu +2 位作者 Fen Tang JingYuan Li Meng Sun 《Earth and Planetary Physics》 EI CAS CSCD 2024年第2期356-367,共12页
Utilizing observations by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument,we quantitatively assessed the dawn-dusk asymmetry in temperature disturbances within the high-latitude mes... Utilizing observations by the Sounding of the Atmosphere using Broadband Emission Radiometry(SABER)instrument,we quantitatively assessed the dawn-dusk asymmetry in temperature disturbances within the high-latitude mesosphere and lower thermosphere(MLT)during the main phase of geomagnetic storms in this study.An analysis of five geomagnetic superstorm events indicated that during the main phase,negative temperature disturbances were more prevalent on the dawn side than on the dusk side in the high-latitude MLT region.Results of a statistical analysis of 54 geomagnetic storm events also revealed a notable disparity in temperature disturbances between the dawn and dusk sides.At high latitudes,38.2%of the observational points on the dawn side exhibited negative temperature disturbances(less than−5 K),whereas on the dusk side,this percentage was only 29.5%.In contrast,at mid-latitudes,these proportions were 34.1%and 36.5%,respectively,showing no significant difference.We also conducted a statistical analysis of temperature disturbances at different altitudes,which revealed an increase in the proportion of warming disturbances with altitude.Conversely,the proportion of cooling disturbances initially rose with altitude,reaching a peak around 105 km,and subsequently decreased.These temperature disturbance differences could be explained by the day-night asymmetry in vertical wind disturbances during storm conditions. 展开更多
关键词 DAWN dusk asymmetry SABER(Sounding of the Atmosphere using Broadband Emission Radiometry) geomagnetic storms mesosphere and lower thermosphere
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Advances in the management of arteriosclerosis of the lower extremity:Integrating Western and Chinese medicine approaches
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作者 Sha Cheng Jia-Xin Xu Wen-Jie Long 《World Journal of Clinical Cases》 SCIE 2024年第36期6871-6876,共6页
This editorial provides a commentary on the recent article.The paper reviews current literature and explores innovative treatment strategies for lower extremity arteriosclerosis obliterans(LEASO)through an integrative... This editorial provides a commentary on the recent article.The paper reviews current literature and explores innovative treatment strategies for lower extremity arteriosclerosis obliterans(LEASO)through an integrative approach.It highlights the effectiveness of combination therapies that merge traditional Chinese medicine(TCM)with Western medical practices,suggesting that such integrative methods may improve patient compliance and outcomes through personalized care.This paper stresses the importance of rigorous clinical trials to evaluate the efficacy and safety of TCM interventions within LEASO treatment protocols,advocating for evidence-based validation of these combined therapies.Our recommendations emphasize accurate diagnosis,appropriate pharmacological in-terventions,the use of advanced surgical and endovascular techniques,and the inclusion of TCM to address underlying dysfunctions.Additionally,continuous monitoring,patient education,and lifestyle modifications are essential to slow disease progression and achieve optimal patient outcomes.The paper concludes by calling for further research to develop standardized treatment protocols that effectively integrate both Western and Chinese medical approaches in managing LEASO. 展开更多
关键词 lower extremity arteriosclerosis obliterans Traditional Chinese medicine Integrative healthcare Vascular therapy Combination therapies
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Efficacy of percutaneous mechanical thrombus removal in acute lower extremity deep venous thrombosis
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作者 Jun-Qiang Xue Ping Yin +3 位作者 Jian-Ping He Hui Wei Cui-Jie Geng Yu-Xian Luo 《World Journal of Clinical Cases》 SCIE 2024年第21期4590-4600,共11页
BACKGROUND Acute lower extremity deep venous thrombosis(LEDVT)is a common vascular emergency with significant morbidity risks,including post-thrombotic syndrome(PTS)and pulmonary embolism.Traditional treatments like c... BACKGROUND Acute lower extremity deep venous thrombosis(LEDVT)is a common vascular emergency with significant morbidity risks,including post-thrombotic syndrome(PTS)and pulmonary embolism.Traditional treatments like catheter-directed thrombolysis(CDT)often result in variable success rates and complications.AIM To investigate the therapeutic efficacy of percutaneous mechanical thrombus removal in acute LEDVT.METHODS A retrospective analysis was performed to examine 58 hospitalised patients with acute LEDVT between August 2019 and August 2022.The patients were categorised into the percutaneous mechanical thrombectomy(PMT)group(n=24)and CDT group(n=32).The follow-up,safety and treatment outcomes were compared between the two groups.The main observational indexes were venous patency score,thrombus removal effect,complications,hospitalisation duration and PTS.RESULTS The venous patency score was 9.04±1.40 in the PMT group and 8.81±1.60 in the CDT group,and the thrombus clearance rate was 100%in both groups.The complication rate was 8.33%in the PMT group and 34.84%in the CDT group,and the difference was statistically significant(P<0.05).The average hospitalisation duration was 6.54±2.48 days in the PMT group and 8.14±3.56 days in the CDT group.The incidence of PTS was lower in the PMT group than in the CDT group;however,the difference was not statistically significant(P<0.05).CONCLUSION Compared with CDT,treatment of LEDVT via PMT was associated with a better thrombus clearance rate,clinical therapeutic effect and PTS prevention function,but the difference was not statistically significant.Moreover,PMT was associated with a reduced urokinase dosage,shortened hospitalisation duration and reduced incidence of complications,such as infections and small haemorrhages.These results indicate that PMT has substantial beneficial effects in the treatment of LEDVT. 展开更多
关键词 Post-thrombotic syndrome Catheter-directed thrombolysis Percutaneous mechanical thrombectomy Acute lower extremity deep venous thrombosis
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