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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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Monitoring and evaluation of the water quality of the Lower Neches River, Texas, USA 被引量:1
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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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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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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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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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Epidemiological, Clinical and Paraclinical Profile of Osteoarthritis of the Lower Limbs in Obese Patients at the Cocody University Teaching Hospital
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作者 Nzima Brice Kollo Aboubakar Bamba¹ +8 位作者 Aboubacar Sidiki Condé Nzima Hilary Ngon Kanbaye Medom Ada Nina Kpami Yaya Coulibaly Kan Joseph Enoch Koffi Ehaulier Soh Christian Louis Kouakou Mohamed Diomandé¹ Edmond Eti 《Open Journal of Rheumatology and Autoimmune Diseases》 2024年第2期69-76,共8页
Objective: To describe the epidemiological, clinical and paraclinical characteristics of osteoarthritis of the lower limbs in obese patients at the Cocody University Teaching Hospital. Methodology: This was an analyti... Objective: To describe the epidemiological, clinical and paraclinical characteristics of osteoarthritis of the lower limbs in obese patients at the Cocody University Teaching Hospital. Methodology: This was an analytical cross-sectional study carried out in the rheumatology department of the Cocody UTH in Abidjan (Ivory Coast) from March 1 to April 30 2023. Patients who came for rheumatology consultation presenting with mechanical arthralgia of the lower limbs, who were obese, had radiographic images were included. All patients without radiographic images were excluded. Obesity was defined as a body mass index (BMI) greater than or equal to 30 kg/m. The Chi<sup>2</sup> test was used to compare proportions and determine the existence of associations between osteoarthristis and obesity, obesity severity and radiographic stage of osteoarthritis as well as the functional impact. A p-value below a predefined threshold (p = 0,05) indicates a significant relationship between the variables. Result: Out of 185 patients received for osteoarthritis of the lower limbs during the study period, 136 were obese (74%). There were 115 women (84.6%) with an average age of 56.03 with a standard deviation of 12.72 years (extremes: 22 and 84 years). The main socio-professional category was the informal sector (30%). The majority of patients had a low socio-economic level (80.2%) and lived in urban areas (92.6%). The most common past medical history was hypertension (33.08%) followed by peptic ulcer disease (16.91%). Patients had a body mass index class 1 (81.6%), class 2 (15.40%) and class 3 (2.90%). The average duration of symptom progression until diagnosis was 11 months. Genu varum was the main static disorder (56.10%) and the knee joint was the dominant topography (90.4%) with a bilateral localization (80%). The average Lequesne index was greater than 8 (59.5%). The Kellgren and Lawrence radiographic stages were stage 1 (9.20%), stage 2 (46.90%), stage 3 (29.20%) and stage 4 (6.90%). The Obesity severity was significantly associated with osteoarthritis of the knee (p = 0.042). There was no statistically significant association between obesity severity and radiographic stage of osteoarthritis (p = 0.163) or functional impact (p = 0.180). Conclusion: Osteoarthritis of the lower limbs affected obese women and was dominated by stage 2 osteoarthritis of the knee (Kellgren and Lawrence). There is an association between the severity of obesity and osteoarthritis of the knee. 展开更多
关键词 OSTEOARTHRITIS lower Limbs OBESITY ABIDJAN
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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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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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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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Risk Factors for Lower Extremity Amputation among Diabetic Patients with Diabetic Foot Gangrene in ATBUTH, Bauchi
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作者 Stephen Yusuf Shaphat Shuaibu Ibrahim +3 位作者 Abubakar Musa Yusuf Aliyu Salihu Friday Titus Nyako Ngwan David Wujika 《Open Journal of Orthopedics》 2024年第9期391-403,共13页
Background: Diabetic mellitus was described as an evolving global epidemic of the twenty-first century, due to the exponential rise in the number of people with the condition. Lower extremity amputation is one of the ... Background: Diabetic mellitus was described as an evolving global epidemic of the twenty-first century, due to the exponential rise in the number of people with the condition. Lower extremity amputation is one of the common complications of diabetes. With increase in the number of people with diabetes there will also be increase in the number of diabetics going for lower extremity amputation, increasing both the financial as well as psychologic burden of treatment. Methodology: A prospective cross-sectional study of all diabetic patients going for lower extremity amputation will be done. All the patients with advanced diabetic foot syndrome needing lower extremity amputation are enrolled (Wagener stage IV and V), both through the clinic and emergency center. Informed consent is obtained from the patient after which data are collected using a structured questionnaire. All the investigation results of the patients were also documented. Data collected are analyzed using the SPSS version 29. Chi-square and student t-test were used to measure significant relationship between the variables at 95% confident interval. Results: Within the period of study, which extends from 1st January 2022 to 1st of January 2024, a total of 171 patients were recruited. All diabetic patients with diabetic foot Wagener grade IV and V who presented to the clinic or emergency department were enrolled in the study. We found a significant relationship between gender, previous procedure on the affected limb or amputation of the contralateral limb, knowledge of foot care among diabetics and risk of amputation. There was, however, no statistically significant relationship between. There is no statistically significance relationship between the level of education, occupation, presence of co-morbidity with the risk of amputation among diabetic patients with foot syndrome. Conclusion: Previous lower limb procedure/amputation, male gender, paucity of knowledge on foot care, prolonged duration of the disease and method of treatment are important risk factors for the risk of amputation among diabetic patients with diabetic foot syndrome. 展开更多
关键词 Diabetes Mellitus lower Limb AMPUTATION Risk Factors REHABILITATION
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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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Flood Risk Assessment in the Lower Valley of Ouémé, Benin
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作者 Yaovi Aymar Bossa Octave Djangni +3 位作者 Yacouba Yira Jean Hounkpè Angèle D. Avossè Luc Ollivier Sintondji 《Open Journal of Modern Hydrology》 CAS 2024年第2期130-151,共22页
In response to the increased frequency of flood events in recent years, it has become crucial to enhance preparedness and anticipation through precise flood risk assessments. To this end, this study aims to produce up... In response to the increased frequency of flood events in recent years, it has become crucial to enhance preparedness and anticipation through precise flood risk assessments. To this end, this study aims to produce updated and precise flood risk maps for the Lower Valley of Ouémé River Basin, located in the South of Benin. The methodology used consisted of a combination of geographical information systems (GIS) and multi-criteria analysis, including Analytical Hierarchy Process (AHP) methods to define and quantify criteria for flood risk assessment. Seven hydro-geomorphological indicators (elevation, rainfall, slope, distance from rivers, flow accumulation, soil type, and drainage density), four socio-economic vulnerability indicators (female population density, literacy rate, poverty index, and road network density), and two exposure indicators (population density and land use) were integrated to generate risk maps. The results indicate that approximately 21.5% of the Lower Valley is under high and very high flood risk, mainly in the south between Dangbo, So-Ava, and Aguégués. The study findings align with the historical flood pattern in the region, which confirms the suitability of the used method. The novelty of this work lies in its comprehensive approach, the incorporation of AHP for weighting factors, and the use of remote sensing data, GIS technology, and spatial analysis techniques which adds precision to the mapping process. This work advances the scientific understanding of flood risk assessment and offers practical insights and solutions for flood-prone regions. The detailed flood risk indicator maps obtained stand out from previous studies and provide valuable information for effective flood risk management and mitigation efforts in the Lower Valley of Ouémé. 展开更多
关键词 Flood Hazard Exposure VULNERABILITY Risk lower Valley of Ouémé
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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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Intervention Effect of Lower Limb Rehabilitation Robot with Task-Oriented Training on Stroke Patients and Its Influence on KFAROM Score
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作者 Maiding He Li Huang +9 位作者 Dekun Tang Mei Qin Ping Zhan Xichan Wang Xia Gao Jianzhu Wang Na Yin Hui Xu Yonghua Yang Kaihua Tang 《Journal of Biosciences and Medicines》 2024年第9期62-72,共11页
Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to o... Objective: To explore the effect of lower limb rehabilitation robot combined with task-oriented training on stroke patients and its influence on KFAROM score. Methods: 100 stroke patients with hemiplegia admitted to our hospital from January 2023 to December 2023 were randomly divided into two groups, the control group (50 cases) was given task-oriented training assisted by nurses, and the observation group (50 cases) was given lower limb rehabilitation robot with task-oriented training. Lower limb balance, lower limb muscle strength, motor function, ankle function, knee flexion range of motion and walking ability were observed. Results: After treatment, the scores of BBS, quadriceps femoris and hamstrings in the observation group were significantly higher than those in the control group (P Conclusion: In the clinical treatment of stroke patients, the combination of task-oriented training and lower limb rehabilitation robot can effectively improve the lower limb muscle strength, facilitate the recovery of balance function, and have a significant effect on the recovery of motor function, which can improve the walking ability of stroke patients and the range of motion of knee flexion, and achieve more ideal therapeutic effectiveness. 展开更多
关键词 lower Limb Rehabilitation Robot Task-Oriented Training STROKE KFAROM
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Evaluation of Agricultural Contamination Level by Heavy Metals and Pesticides in Sediments of Rivers and Water Bodies for Shrimp Fishing in the Lower Ouémé: Case of the Aguigadji, Ahlan and Sele Stations in Benin
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作者 Souradjou Orou Goura Fadéby Modeste Gouissi +3 位作者 Armelle Sabine Yélignan Hounkpatin Wakili Bolatito Yessoufou Tayéwo Sylvain Biaou Nonvignon Martial Fassinou 《Advances in Materials Physics and Chemistry》 CAS 2024年第2期25-46,共22页
This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochl... This study assessed sediment contamination by heavy metals and pesticide active ingredients linked to chemical inputs used in agricultural activities in the lower Ouémé. Pesticide residues from the organochlorine, pyrethroid and organophosphorus families were investigated by gas chromatography, and heavy metals (Cd, Pb, As, Ni, Zn, Fe, Mg, Cr and Hg) by atomic absorption spectrophotometry. The metallic pollution indices, the contamination factor (CF) and the ecological risk index were calculated. The results revealed 8 active ingredients in the rainy season and 9 in the dry season. Glyphosate was the active ingredient with the highest concentration at all stations, 9.65 ± 0.84 mg/kg recorded in the dry season at the Aguigadji station. All glyphosate values were above the EQS. DDT, Atrazine and Endosulfan also showed high concentrations in the dry and rainy seasons. Emamectin, Abamectin and Lambda Cyhalothrin also showed high concentrations in the dry season at Aguigadji, Ahlan and Sele. Only glyphosate was recorded at the control station (Toho), but in very low concentrations. Lead showed the highest concentrations at all the stations, 265.96 ± 21.02 mg/Kg in the rainy season and 255.38 ± 79.09 mg/Kg in the dry season, all detected at the Aguigadji station and above the EQS. Zn, Ni, Fe, Cu and Cr were all representative in both the dry and rainy seasons at the contaminated stations. Manganese showed high concentrations in the rainy season. Pb showed very high contamination (FC ≥ 6) at the Aguigadji and Ahlan stations and significant contamination (3 ≤ FC 6) at the Sele station in both the rainy and dry seasons. Ni, Hg and Cd, showed either moderate or significant contamination at the contaminated stations. The risk values showed a considerable ecological Ri (190 ≤ Ri < 380) in the rainy season and a moderate ecological Ri (95 ≤ Ri < 190) in the dry season at these contaminated stations. 展开更多
关键词 PESTICIDES Heavy Metals SEDIMENTS Shrimp Fishing Area lower Ouémé
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Management of Square Carcinoma of the Lower Lip Using Camille-Bernard Flap under Local Anesthesia: When Constraints Dictate Our Attitude
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作者 Silly Toure Mouhamadou Makhtar Ndiaye +3 位作者 Abibou Ndiaye Mame Sanou Diouf Birame Loum Baye Karim Diallo 《Open Journal of Stomatology》 2024年第4期191-197,共7页
Introduction: Squamous cell carcinomas of the lip essentially pose a therapeutic management problem. In the West, their treatment is done under general anesthesia and follows the classic rules of oncology. In our cont... Introduction: Squamous cell carcinomas of the lip essentially pose a therapeutic management problem. In the West, their treatment is done under general anesthesia and follows the classic rules of oncology. In our context of exercise, we sometimes have a different attitude dictated by various constraints. Observation: 55-year-old patient with no notable history, seen in consultation for a very large ulcerative-budding lesion on the right 2/3 of the lower lip with mucocutaneous involvement without lymph node findings found on examination. Faced with this suspicious lesion and the patient’s financial difficulties, we decided to operate under local anesthesia to remove this tumor. The oncological excision was followed by immediate plasty using a Camille-Bernard flap with a good immediate aesthetic and functional result and postoperative day 7. The patient was unable to take his surgical specimen to anatomy-pathology and was lost to follow-up due to lack of financial resources. On anatomo-pathological analysis of the surgical specimen, the margins were healthy with confirmation of squamous cell carcinoma (anapathological reading made for scientific interest). Discussion: The particular mentality of certain patients and their difficult financial conditions push us to have an unconventional therapeutic attitude in oncology, but which nevertheless makes it possible to resolve certain problems that we often face. Local anesthesia is possible and realistic in cases like ours and the results can be acceptable and life-saving. 展开更多
关键词 Squamous Cell Carcinoma lower Lip Camille Bernard Flap Local Anesthesia
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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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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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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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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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