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Foreign Bodies in the Lower Airways: Patient Pathways and Management at the ENT Department of Donka National Hospital, Guinea
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作者 Ibrahima Diallo Mamadou Mouctar Ramata Diallo +13 位作者 Ismaël Dabo Sayon Kourouma Mamadou Aliou Diallo Alseny Camara Alseny Cissé Raphan Mady Kaba Keïta Aminata G. Diallo Mamadou Cellou Bah Youssouf Bapaté Barry Alpha Oumar Barry Abdoulaye Bayo Mohamed Casimir Kaman Abdoulaye Keita Alpha Oumar Diallo 《International Journal of Otolaryngology and Head & Neck Surgery》 2025年第1期39-46,共8页
Introduction: Foreign bodies (FB) in the lower airways (LAs) constitute a potentially life-threatening emergency requiring immediate management. The objective of our study was to describe the patient pathway and manag... Introduction: Foreign bodies (FB) in the lower airways (LAs) constitute a potentially life-threatening emergency requiring immediate management. The objective of our study was to describe the patient pathway and management of foreign bodies in the lower airways. Methodology: This was a descriptive study with retrospective data collection conducted over a 6-year period (January 1, 2014, to December 31, 2019) in the ENT and Head and Neck Surgery Department of Donka National Hospital. Results: We observed a prevalence of 1.79%. The average age was 5.71 years, with a sex ratio of 1.2. However, 82.61% of the cases originated from rural areas. We noted that 78.83% of patients were referred after visiting 1 to 2 healthcare facilities (75.36%). The consultation delay was 3 days. Penetration syndrome was present in 98.56% of cases. The foreign body incidents occurred during play in 54.84% and during meals in 29.09% of cases. Radiographs were performed in 93.9% of cases. Endoscopy was used for both diagnostic and therapeutic purposes in all patients. The foreign bodies were located in the trachea (37.68%), larynx (26.08%), and bronchi (21.73%). Non-organic foreign bodies were predominant (52.17%). Postoperative outcomes were uncomplicated in 95.98% of cases, and the lethality rate was 2.85%. Conclusion: The pathway of patients with foreign bodies in the airways remains unpredictable in our context due to parental hesitations. Early management reduces morbidity and mortality rates. 展开更多
关键词 PATHWAY Foreign Bodies lower Airways Treatment GUINEA
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Surgical Management of Varicose Veins of the Lower Limbs: Retrospective Study of 280 Patients
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作者 Papa Amath Diagne Abdoul Aziz Thiaw +14 位作者 Momar Sokhna Diop Ndeye Fatou Sow Abdoul Ahad Mbengue Papa Ousmane Ba Mory Camara Soda Mareme Mbaye Moussa Seck Diop Jean Claude Dione Abdoul Khoudoss Diallo Moussa Mareme Samba Ibrahima Wade Anta Mbaye Sall Magaye Gaye Papa Adama Dieng Amadou Gabriel Ciss 《Surgical Science》 2025年第2期110-114,共5页
Varicose veins of the lower limbs are a cosmopolitan condition, thought to be rare in Africa but widespread in Europe. The aim of this study is to analyze the indications and evaluate the results of surgical managemen... Varicose veins of the lower limbs are a cosmopolitan condition, thought to be rare in Africa but widespread in Europe. The aim of this study is to analyze the indications and evaluate the results of surgical management of varicose pathology of the IM in Dakar. We enrolled 280 patients, with a mean age of 36 and a sex ratio of 2. Factors favouring venous disease were dominated by prolonged orthostatism and multiparity. The average consultation time was 6 years. The reasons for consultation were functional manifestations, progressive complications and aesthetics. The venous trunks concerned were the great saphenous vein (GSV) in 58.9% of cases, the small saphenous vein (SSV) in 29% of cases, perforating veins and varicose veins were unsystematized in 28.5% of cases. Surgery was performed under spinal anaesthesia. Surgical procedures were dominated by stripping of the GSV, crossectomy of the SSV and staged ligations. One patient developed meningismus immediately after the operation. Average follow-up was 2 years. Mortality was null. 展开更多
关键词 Varicose Veins lower Limbs STRIPPING
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Open Lower Limb Trauma in Children
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作者 Abakar Djibrine Mahamat-Nour Olivier N’garinguem +3 位作者 Bembo Lamega Ali Haouane Nazira Kalki Djiannone Ouchemi Choua 《Open Journal of Orthopedics》 2025年第2期110-116,共7页
Purpose: To evaluate open lower limb trauma management in children. Me-thod: We conducted a twelve-month cross-sectional prospective study. Results: Open trauma of lower limb had 7.9% of hospital frequency. Mean age w... Purpose: To evaluate open lower limb trauma management in children. Me-thod: We conducted a twelve-month cross-sectional prospective study. Results: Open trauma of lower limb had 7.9% of hospital frequency. Mean age was 8 years with a sex ratio of 2.45. In 68.4% of cases, trauma occurred in road traffic accidents. Average consultation time was 2.4 hours. Trauma mainly affected the leg in 39.5% of cases, and the thigh in 34.2%. Soft tissue wounds occurred in 52.6% of cases, and open fractures in 47.4%. Average response time was one hour. Wound trimming and suturing were performed in 76.3% of cases and combined with bone nailing in 15.8%. The outcome was favorable in 92.1% of cases. Average hospital stay was 4.37 days. Conclusion: Open trauma to the lower limb is a frequent and occurs mainly in road traffic accidents. Management was early, with a favorable outcome for most patients and a short hospital stay. 展开更多
关键词 Open Trauma Open Fractures lower Limb CHILDREN CHUME CHAD
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Effects of hyperalkaline solutions on the water retention properties and microstructure of the opalinus clay from the lower sandy facies of mont terri site,Switzerland
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作者 Yara Barakat Nadia Mokni +2 位作者 Yu-Jun Cui Pierre Delage Frédéric Bernier 《Journal of Rock Mechanics and Geotechnical Engineering》 2025年第3期1723-1737,共15页
In Switzerland,the Opalinus Clay has been selected as a potential host rock for the deep geological disposal of radioactive waste due to its low hydraulic conductivity and favorable swelling properties.During the oper... In Switzerland,the Opalinus Clay has been selected as a potential host rock for the deep geological disposal of radioactive waste due to its low hydraulic conductivity and favorable swelling properties.During the operational phase of the repository,the host rock will be exposed to pH values as high as 13.5 due to concrete degradation,which will certainly affect its hydraulic properties.This study investigates the effect of pH increase on the water retention properties of Opalinus Clay.A series of samples from the lower sandy facies of the Mont Terri site in Switzerland,at initial dry state,were exposed to a hyperalkaline solution of pH=13.5 and to the synthetic water of pH=7.5 at different water contents.After equilibrium,the total suction was measured with a dew point potentiometer and microstructural analyses were conducted via mercury intrusion porosimetry(MIP)and nitrogen adsorption-desorption technique.It was found that the total suction decreased with hydration and pH increase.Since the two investigated solutions have the same osmotic suction,the decrease in total suction was attributed to the decrease in matric suction.Indeed,the total porosity increased with saturation and pH increase.This was confirmed by MIP data that evidenced an increase in the proportion of macropores,and by Barret eJoynereHalenda(BJH)data that showed mesopore generation.The specific surface area(SSA)also increased.The previous results were due to mineral hydration and,exclusively in the case of alkaline solution,to(1)the dissolution of quartz and calcite and(2)the acid-base reactions,which were concentrated at the edges of the clay particles,leading to an increase in negatively charged groups and thus to a face-to-face association of the clay particles(dispersion),causing an increase in the repulsive forces between the clay particles.In addition,the weakening of covalent bonds led to the primary dissolution of clay minerals,i.e.silicon and aluminum detachment. 展开更多
关键词 Opalinus clay lower sandy facies Water retention properties Porosity MICROSTRUCTURE DISSOLUTION
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Metastatic lymph node distribution and pathology correlations in upper and lower gastric cancer patients:A multicenter retrospective study
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作者 Xian-Bei Yuan Gang Sun +3 位作者 Jun Niu Lei Dong Yi Sui Yong-Zhu Lv 《World Journal of Gastrointestinal Oncology》 2025年第2期56-66,共11页
BACKGROUND Gastric cancer(GC)poses a significant threat to public health.However,the clinicopathological features and tumor biological behaviors vary among the GC patients,leading to individual variations in lymph nod... BACKGROUND Gastric cancer(GC)poses a significant threat to public health.However,the clinicopathological features and tumor biological behaviors vary among the GC patients,leading to individual variations in lymph node metastasis.Consequently,the stratification of lymph node dissection according to the specific type,particularly upper GC,has emerged as a prominent area of research.AIM To investigate the distribution of metastatic lymph nodes in patients with upper and lower GC and to analyze the differences in related pathological elements and prognosis.METHODS Differential analysis between upper and lower GC patients with various clinicopathological factors was performed using the chi-square test and rank-sum regression models were used to analyze risk factors affecting patient prognosis.The Kaplan-Meier method was used to construct survival curves associated with prognostic risk factors for GC.RESULTS Significant differences were observed between the two GC populations regarding tumor diameter,histological grade,pT stage,pN stage,tumor-node-metastasis(pTNM)stage,vascular invasion,and adjuvant chemotherapy usage(all P<0.05).Lymph node metastasis rates were highest for Siewert type II patients in groups Nos.1,3,2 and 7;for Siewert type III patients in groups Nos.3,1,2 and 7;and for other/unclassified patients in groups Nos.1,3,7,2.In the lower GC samples,the sequences were Nos.3,6,7,4.Pathological type,pT stage,pTNM stage,and positive vascular invasion were independent risk factors for development of lymph node metastasis.Age,pathological type,pT stage,pN stage,pTNM stage,vascular invasion,and absence of adjuvant chemotherapy were identified as independent prognostic factors.CONCLUSION Upper GC showed a significantly higher malignancy grade and different lymph node metastasis pattern than lower GC. 展开更多
关键词 Upper gastric cancer lower gastric cancer Metastatic lymph nodes Prognosis Retrospective study
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Association between serum retinol-binding protein and lower limb atherosclerosis risk in type 2 diabetes mellitus
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作者 Yu-Ling Zhang Gui-Liang Peng +6 位作者 Wei-Ling Leng Yu Lian Li-Qing Cheng Xing Li Yu-Lin Wang Ling Zhou Min Long 《World Journal of Diabetes》 2025年第3期76-88,共13页
BACKGROUND Serum retinol-binding protein(RBP)is the primary transport protein of circulating vitamin A.RBP has a crucial role in maintaining nutrient metabolism and physiologic homeostasis.Several studies have indicat... BACKGROUND Serum retinol-binding protein(RBP)is the primary transport protein of circulating vitamin A.RBP has a crucial role in maintaining nutrient metabolism and physiologic homeostasis.Several studies have indicated that serum RBP participates in the progression of diabetes and diabetes-related complications.However,the impact of serum RBP on lower limb atherosclerosis has not been determined in individuals with type 2 diabetes mellitus(T2DM).AIM To determine the association between serum RBP and lower limb atherosclerosis in individuals with T2DM.METHODS This retrospective study enrolled 4428 eligible T2DM patients and divided the patients into non-lower limb atherosclerosis(n=1913)and lower limb atherosclerosis groups(n=2515)based on lower limb arterial ultrasonography results.At hospital admission,baseline serum RBP levels were assessed,and all subjects were categorized into three groups(Q1-Q3)based on RBP tertiles.Logistic regression,restricted cubic spline regression,subgroup analysis,and machine learning were used to assess the association between RBP levels and lower limb atherosclerosis risk.RESULTS Among 4428 individuals with T2DM,2515(56.80%)had lower limb atherosclerosis.Logistic analysis showed that lower limb atherosclerosis risk increased by 1%for every 1 unit rise in serum RBP level(odds ratio=1.01,95%confidence interval:1.00-1.02,P=0.004).Patients in the highest tertile group(Q3)had a higher lower limb atherosclerosis risk compared to the lowest tertile group(Q1)(odds ratio=1.36,95%confidence interval:1.12-1.67,P=0.002).The lower limb atherosclerosis risk gradually increased with an increase in RBP tertile(P for trend=0.005).Restricted cubic spline analysis indicated a linear correlation between serum RBP levels and lower limb atherosclerosis risk(non-linear P<0.05).Machine learning demonstrated the significance and diagnostic value of serum RBP in predicting lower limb atherosclerosis risk.CONCLUSION Elevated serum RBP levels correlate with an increased lower limb atherosclerosis risk in individuals with T2DM. 展开更多
关键词 Retinol-binding protein Type 2 diabetes mellitus lower limb atherosclerosis Peripheral arterial disease BIOMARKER
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Predicting Summer Precipitation in the Middle and Lower Reaches of the Yangtze River Using Winter Sea Surface Temperature Anomalies and Trends
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作者 YANG Jian XING Wen LIU Fei 《Journal of Tropical Meteorology》 2025年第1期120-132,共13页
Studying the causes of summer(June–July–August)precipitation anomalies in the middle and lower reaches of the Yangtze River(MLYR)and accurately predicting rainy season precipitation are important to society and the ... Studying the causes of summer(June–July–August)precipitation anomalies in the middle and lower reaches of the Yangtze River(MLYR)and accurately predicting rainy season precipitation are important to society and the economy.In recent years,the sea surface temperature(SST)trend factor has been used to construct regression models for summer precipitation.In this study,through correlation analysis,winter SST anomaly predictors and the winter Central Pacific SST trend predictor(CPT)are identified as closely related to the following MLYR summer precipitation(YRSP).CPT can influence YRSP by inducing anomalous circulations over the North Pacific,guiding warm and moist air northward,and inhibiting the development of the anomalous anticyclone over the Northwest Pacific.This has improved the predictive skill of the seasonal regression model for YRSP.After incorporating the CPT,the correlation coefficient of the YRSP regression model improved by 40%,increasing from 0.45 to 0.63,and the root mean squared error decreased by 22%,from 1.15 to 0.90. 展开更多
关键词 sea surface temperature anomalies sea surface temperature variation trend middle and lower reaches of the Yangtze River seasonal prediction
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Equilibria of the Abstract Economy under Almost Lower Semi-continuous Assumption 被引量:1
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作者 张玉成 陈福川 《Northeastern Mathematical Journal》 CSCD 2003年第1期26-32,共7页
The purpose of this paper is to make a further study on the abstract economy. Here, for the constraint correspondences we assume that they are almost lower semi-continuous (n-lower semi-continuous), which is weaken th... The purpose of this paper is to make a further study on the abstract economy. Here, for the constraint correspondences we assume that they are almost lower semi-continuous (n-lower semi-continuous), which is weaken than that they are lower semi-continuous. Several equilibria existence theorems are proved. 展开更多
关键词 almost lower semi-continuity ε-approximate selection EQUILIBRIUM
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Fuzzy Semi-continuity of fuzzy number-valued function 被引量:3
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作者 Magassy OUS MANE 吴从炘 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2002年第2期139-141,共3页
In this paper we discuss the conecept and property of fuzzy semi continuous function.
关键词 FUZZY NUMBERS FUZZY number-valued FUNCTION FUZZY semi-continuOUS FUNCTION
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Sub-Differential Characterizations of Non-Smooth Lower Semi-Continuous Pseudo-Convex Functions on Real Banach Spaces
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作者 Akachukwu Offia Ugochukwu Osisiogu +4 位作者 Theresa Efor Friday Oyakhire Monday Ekhator Friday Nkume Sunday Aloke 《Open Journal of Optimization》 2023年第3期99-108,共10页
In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Su... In this paper, we characterize lower semi-continuous pseudo-convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the pseudo-monotonicity of its Clarke-Rockafellar Sub-differential. We extend the results on the characterizations of non-smooth convex functions f : X → R ∪ {+ ∞} on convex subset of real Banach spaces K  ⊂ X with respect to the monotonicity of its sub-differentials to the lower semi-continuous pseudo-convex functions on real Banach spaces. 展开更多
关键词 Real Banach Spaces Pseudo-Convex Functions Pseudo-Monotone Maps Sub-Differentials lower semi-continuous Functions and Approximate Mean Value Inequality
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Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South China 被引量:3
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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 被引量:1
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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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Upper semi-continuity of attractors for multivalued semi-flow under random perturbation
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作者 李挺 刘曾荣 《Journal of Shanghai University(English Edition)》 CAS 2006年第4期288-292,共5页
In this paper the upper semi-continuity of global attractors for multivalued semi-flows under random perturbation was studied. First, the existence of random attractors for multivalued random semi-flows was considered... In this paper the upper semi-continuity of global attractors for multivalued semi-flows under random perturbation was studied. First, the existence of random attractors for multivalued random semi-flows was considered, then it was proved that the global attractors for multivalue semi-flows are the upper semi-continuity under random perturbation. This result can be used in the numerical approximation of multivalued semi-flows and non-autonomous perturbation of multivalued semi-flows. 展开更多
关键词 random attractor upper semi-continuity absorbing set.
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Intervention Effect of Lower Limb Rehabilitation Robot with Task-Oriented Training on Stroke Patients and Its Influence on KFAROM Score 被引量:1
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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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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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Model Parameters Identification and Backstepping Control of Lower Limb Exoskeleton Based on Enhanced Whale Algorithm 被引量:1
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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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Existence and Upper Semi-Continuity of Random Attractors for Nonclassical Diffusion Equation with Multiplicative Noise on Rn
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作者 Fadlallah Mustafa Mosa Abdelmajid Ali Dafallah +2 位作者 Qiaozhen Ma Eshag Mohamed Ahmed Mohamed Y. A. Bakhet 《Journal of Applied Mathematics and Physics》 2022年第12期3898-3919,共22页
This paper is concerned with the existence and upper semi-continuity of random attractors for the nonclassical diffusion equation with arbitrary polynomial growth nonlinearity and multiplicative noise in H<sup>1... This paper is concerned with the existence and upper semi-continuity of random attractors for the nonclassical diffusion equation with arbitrary polynomial growth nonlinearity and multiplicative noise in H<sup>1</sup>(R<sup>n</sup>). First, we study the existence and uniqueness of solutions by a noise arising in a continuous random dynamical system and the asymptotic compactness is established by using uniform tail estimate technique, and then the existence of random attractors for the nonclassical diffusion equation with arbitrary polynomial growth nonlinearity. As a motivation of our results, we prove an existence and upper semi-continuity of random attractors with respect to the nonlinearity that enters the system together with the noise. 展开更多
关键词 Random Attractors Nonclassical Diffusion Equations Asymptotic Compactness Upper semi-continuity
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Research progress on semi-continuous casting of magnesium alloys under external field
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作者 Qi-yu Liao Qi-chi Le +3 位作者 Da-zhi Zhao Lei Bao Tong Wang Yong-hui Jia 《China Foundry》 SCIE EI CAS CSCD 2024年第5期516-524,共9页
High-performance magnesium alloys are moving towards a trend of being produced on a large scale and in an integrated manner.The foundational key to their successful production is the high-quality cast ingots.Magnesium... High-performance magnesium alloys are moving towards a trend of being produced on a large scale and in an integrated manner.The foundational key to their successful production is the high-quality cast ingots.Magnesium alloys produced through the conventional semi-continuous casting process inevitably contain casting defects,which makes it challenging to manufacture high-quality ingots.The integration of external field assisted controlled solidification technology,which combines physical fields such as electromagnetic and ultrasonic fields with traditional semi-continuous casting processes,enables the production of high-quality magnesium alloy ingots characterized by a homogeneous microstructure and absence of cracks.This article mainly summarizes the technical principles of those external field assisted casting process.The focus is on elaborating the refinement mechanism of different types of electromagnetic fields,ultrasonic fields,and combined physical fields during the solidification of magnesium alloys.Finally,the development prospects of producing highquality magnesium alloy ingots through semi-continuous casting under the external field were discussed. 展开更多
关键词 semi-continuous casting electromagnetic field ultrasonic field magnesium alloys refinement mechanism
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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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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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