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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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Organic Matter Accumulation in the Upper Permian Dalong Formation from the Lower Yangtze Region,South China
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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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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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Optimization of Generator Based on Gaussian Process Regression Model with Conditional Likelihood Lower Bound Search
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作者 Xiao Liu Pingting Lin +2 位作者 Fan Bu Shaoling Zhuang Shoudao Huang 《CES Transactions on Electrical Machines and Systems》 EI CSCD 2024年第1期32-42,共11页
The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regressi... The noise that comes from finite element simulation often causes the model to fall into the local optimal solution and over fitting during optimization of generator.Thus,this paper proposes a Gaussian Process Regression(GPR)model based on Conditional Likelihood Lower Bound Search(CLLBS)to optimize the design of the generator,which can filter the noise in the data and search for global optimization by combining the Conditional Likelihood Lower Bound Search method.Taking the efficiency optimization of 15 kW Permanent Magnet Synchronous Motor as an example.Firstly,this method uses the elementary effect analysis to choose the sensitive variables,combining the evolutionary algorithm to design the super Latin cube sampling plan;Then the generator-converter system is simulated by establishing a co-simulation platform to obtain data.A Gaussian process regression model combing the method of the conditional likelihood lower bound search is established,which combined the chi-square test to optimize the accuracy of the model globally.Secondly,after the model reaches the accuracy,the Pareto frontier is obtained through the NSGA-II algorithm by considering the maximum output torque as a constraint.Last,the constrained optimization is transformed into an unconstrained optimizing problem by introducing maximum constrained improvement expectation(CEI)optimization method based on the re-interpolation model,which cross-validated the optimization results of the Gaussian process regression model.The above method increase the efficiency of generator by 0.76%and 0.5%respectively;And this method can be used for rapid modeling and multi-objective optimization of generator systems. 展开更多
关键词 Generator optimization Gaussian Process Regression(GPR) Conditional Likelihood lower Bound Search(CLLBS) Constraint improvement expectation(CEI) Finite element calculation
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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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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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Spatial-temporal Variation Characteristics of Water Quality in the Lower Reaches of the Nenjiang River
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作者 Xiangzhe MENG Jing WANG +4 位作者 Yinglin XIE Fei PENG Chunsheng WEI Xin TIAN Lunwen WANG 《Meteorological and Environmental Research》 2024年第1期67-71,共5页
As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wet... As an important river in the western part of Jilin Province,the lower reach of the Nenjiang River is an important wetland water source conservation area in Jilin Province.Within the watershed,it governs the Momoge Wetland,the Xianghai Wetland,and the Danjiang Wetland in Jilin Province.The main problem in the lower reaches of the Nenjiang River is the uneven distribution of water resources in time and space,and the intensification of land salinization.Zhenlai County and Da an City in the Nenjiang River Basin have sufficient surface water resources,with surface water as the drinking water source.Baicheng City and Tongyu County have scarce surface water resources,and both use groundwater as their domestic water source.The main polluted section in the basin is the Xianghai Reservoir,and the annual water quality evaluation is Class V.However,the water quality of the Tao er River,the main stream of the Nenjiang River,is significantly better than that of the Xianghai Reservoir.In order to better study the water environmental pollution situation in the Nenjiang River basin,monitoring data from five sections of non seasonal rivers in the basin from 2012 to 2021 were selected for studying water quality.This in-depth exploration of the water pollution status and river water quality change trends in the Nenjiang River basin is of great significance for future rural development,agricultural pattern transformation,and the promotion of water ecological civilization construction. 展开更多
关键词 lower reaches of the Nenjiang River Water quality Spatial-temporal variation
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Relationships between Quadriceps:Hamstring Strength Ratio and Lower Extremity Injuries in Netball Players
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作者 Henriette Hammill 《Open Journal of Applied Sciences》 2024年第4期1022-1033,共12页
Background: Netball is a popular sport. Due to high impact and quick movement, there is an enormous load on the lower extremities which increases the risk for injury. Aim: The aim of this study was to investigate the ... Background: Netball is a popular sport. Due to high impact and quick movement, there is an enormous load on the lower extremities which increases the risk for injury. Aim: The aim of this study was to investigate the relationship between the quadricep and hamstring strength and the prevalence of lower extremity injuries in netball players. Setting: Twenty-five female netball players (age: 20.8 ± 1.4 years) voluntarily participated. Methods: The Cybex Isokinetic dynamometer was used to determine concentric knee torques. Quadriceps:hamstring strength ratio was determined. Occurrence of lower extremity injuries was documented bi-weekly. Results: Medium effect sizes were noted for flexion torque:work for the left leg and for the quadriceps:hamstring ratio (≥60%) for the right leg. All the other measured variables have a small effect size. 18.75% of lower extremity injuries and ConQ:ConH of Conclusion: Injuries to the ankle and knee are especially common among netball players. Hamstring and quadriceps muscle asymmetry (>10%) were found to be a potential indicator of lower extremity injury. Contribution: This study highlights awareness on lower extremity injuries and the strength ratio between the quadriceps and hamstrings. This can aid coaches and netball players to lower the risk for injuries and thus improve individual- and team performance. 展开更多
关键词 Netball HAMSTRINGS QUADRICEPS Strength Ratio lower Extremity Injuries
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Analysis of the Current Situation and Risk Factors of Lower Respiratory Tract Infection among ICU Patients in Guizhou,China During 2019-2022
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作者 Rong Liu Hui Zeng +7 位作者 Jing Zhou Lorna K.P.Suen Min-jiang Qian Jie Wan Sheng-shuang Long Lu-wen Luo Chuan-li Cheng Na-na Yang 《Journal of Clinical and Nursing Research》 2024年第2期76-85,共10页
Objective:This study aims to explore the prevalence,features,and risk factors of lower respiratory tract infections(LRTIs)in the intensive care unit(ICU)of a newly established hospital in Zunyi City.The goal is to dev... Objective:This study aims to explore the prevalence,features,and risk factors of lower respiratory tract infections(LRTIs)in the intensive care unit(ICU)of a newly established hospital in Zunyi City.The goal is to devise strategies for preventing LRTIs in the ICU of new hospitals,thereby mitigating the incidence of nosocomial LRTIs in ICU patients.Methods:A case-control study was conducted from March 2019 to December 2022 to investigate the incidence rate of LRTIs in the ICU of a newly constructed hospital in Zunyi City.Patients with LRTIs constituted the case group,while those without LRTIs constituted the control group,where a 1:1 matching principle was adhered to.A single-factor chi-square(χ2)test was employed to analyze the risk factors,with independent risk factors being explored using a multivariate logistic regression analysis.Results:A total of 169 strains of pathogenic bacteria were isolated,comprising 66.28%gram-negative bacteria,17.75%gram-positive bacteria,and 15.97%fungi.The most prevalent pathogens included Acinetobacter baumannii(43.20%),Candida albicans(10.65%),and Pseudomonas aeruginosa(8.88%).Of the 82 strains infected by multidrug-resistant bacteria in patients with LRTIs,81.7%were carbapenem-resistant Acinetobacter baumannii,9.8%were multidrug-resistant Pseudomonas aeruginosa,and 6.1%were carbapenem-resistant Escherichia coli.Identified risk factors included smoking history,total hospitalization days,ICU stay length,hypoproteinemia,indwelling gastric tube,intubation type,duration of mechanical ventilation,usage of antibacterial drugs,and administration of protein drugs(P<0.05).Multivariate logistic regression analysis demonstrated that these factors were independent risk factors for nosocomial LRTIs in ICU patients(P<0.05).Conclusion:ICU patients in our hospital were mainly infected by carbapenem-resistant Acinetobacter baumannii.To prevent LRTIs in patients,tailored preventive measures should be developed and the rational use of antibacterial drugs should be promoted. 展开更多
关键词 lower respiratory tract infection Risk factors New hospital Intensive care unit
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A Clinical Randomized Controlled Study of Low-Frequency rTMS Therapy on Lower Limb Motor Dysfunction after Stroke
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作者 Kaiqi Huang Xizhen Jie +1 位作者 Xiaoyan Li Zhaoming Liang 《Journal of Clinical and Nursing Research》 2024年第2期212-219,共8页
Objective:To investigate the efficacy and safety of low-frequency repetitive transcranial magnetic stimulation(rTMS)for the treatment of lower limb motor dysfunction after stroke.Methods:A total of 96 patients with st... Objective:To investigate the efficacy and safety of low-frequency repetitive transcranial magnetic stimulation(rTMS)for the treatment of lower limb motor dysfunction after stroke.Methods:A total of 96 patients with stroke and lower limb motor dysfunction were enrolled in this study,and were randomly divided into the experimental group and the sham stimulation group using the method of calculator-generated random numbers.Both groups received conventional medication and rehabilitation therapy.The experimental group received 4 weeks of 1 Hz rTMS treatment in the primary cortical motor area(M1)of the healthy side,with the treatment coil tangent to the skull surface;the sham stimulation group underwent the same procedures as the experimental group,but the treatment coil was perpendicular to the skull surface instead.Lower-extremity subscale of the Fugl-Meyer Assessment(FMA-LE),Berg Balance Scale(BBS),gait analysis,and lower-extremity surface electromyography(LESEM)were performed in both groups before and after rTMS treatment.Results:All 96 patients completed the test with no shedding and no adverse reactions.After treatment,the FMA-LE score and BBS score of the 2 groups of patients were significantly improved as compared with the pre-treatment(P<0.05),and the TUG test time was reduced as compared with the pre-treatment(P<0.05).The true stimulation group had greater improvement in all assessment indexes than that of the sham stimulation group(P<0.05).After treatment,the electromyographic activity of the tibialis anterior and rectus femoris muscles in the true simulation group improved significantly.The step length,step speed,and step frequency were also significantly improved in both groups after treatment,and the symmetrical ratio of step length and support time was reduced(P<0.05).Comparison between the groups revealed that the true simulation group significantly improved after rTMS treatment as compared to the sham stimulation group(P<0.05).Conclusion:1Hz rTMS treatment safely and effectively improved motor and balance function in patients with post-stroke lower limb motor dysfunction. 展开更多
关键词 Repetitive transcranial magnetic stimulation Three-dimensional gait analysis Electromyography stroke lower limb dysfunction rehabilitation
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Lower limb amputation rehabilitation status in India: A review
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作者 Raktim Swarnakar Shiv Lal Yadav Darshana Surendran 《World Journal of Clinical Cases》 SCIE 2023年第30期7261-7267,共7页
Rehabilitation of lower limb amputation in developing countries is quite challenging.Though there are basic to highly advanced prostheses available in India,the set-up is still facing difficulties in developing countr... Rehabilitation of lower limb amputation in developing countries is quite challenging.Though there are basic to highly advanced prostheses available in India,the set-up is still facing difficulties in developing countries.Prosthetic management is difficult due to lack of availability of prostheses and reduced affordability among low income populations.In this review we highlighted the lower limb amputation and prosthetic rehabilitation status in India.Currently,India is advancing well in the rehabilitation field,but further studies are required to provide more evidence and recommendation. 展开更多
关键词 AMPUTATION lower limb amputation PROSTHESIS REHABILITATION lower limb prosthesis Prosthetic rehabilitation
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Some Characterizations of Upper and Lower M-Asymmetric Preirresolute Multifunctions
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作者 Levy Kahyata Matindih Elijah Bwanga Mpelele +1 位作者 Jimmy Hambulo Davy Kabuswa Manyika 《Advances in Pure Mathematics》 2023年第5期267-283,共17页
In this present paper, we introduce and investigate a new form of mappings namely;upper and lower M-asymmetric preirresolute multifunctions defined between M-structural asymmetric topological spaces. The relationships... In this present paper, we introduce and investigate a new form of mappings namely;upper and lower M-asymmetric preirresolute multifunctions defined between M-structural asymmetric topological spaces. The relationships between the multifunctions in our sense and other types of precountinuous and preirresolute multifunctions defined on both symmetric and asymmetric topological structures are discussed. 展开更多
关键词 Asymmetric-Preopen Sets M-Space M-Asymmetric Preopen Sets Upper (lower) Preirresolute Multifunctions Upper (lower) M-Asymmetric Preirresolute Multifunctions
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A New Species of Jiangxialepis(Galeaspida)from the Lower Telychian(Silurian)of Jiangxi and its Biostratigraphic Significance 被引量:3
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作者 SHAN Xianren ZHAO Wenjin GAI Zhikun 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2023年第2期393-403,共11页
A new species of Shuyuidae(Eugaleaspiformes,Galeaspida),Jiangxialepis jiujiangensis sp.nov.,is described from the lower Telychian(Llandovery,Silurian)Qingshui Formation in Jiujiang,Jiangxi Province,China.The new speci... A new species of Shuyuidae(Eugaleaspiformes,Galeaspida),Jiangxialepis jiujiangensis sp.nov.,is described from the lower Telychian(Llandovery,Silurian)Qingshui Formation in Jiujiang,Jiangxi Province,China.The new species differs from the type species J.retrospina from Wuhan,Hubei Province in its sharp and posteriorly positioned median dorsal spine and narrow spine-shaped inner cornual processes.The Silurian strata in Xiushui–Wuning area has provided a standard framework for the correlation of Silurian shallow marine red beds in South China.Thus,the finding of J.jiujiangensis from the Silurian Lower Red Beds(LRBs)in Jiangxi Province bears very important biostratigraphic significance.It can directly compare to Jiangxialepis retrospina from the Fentou Formation in Wuhan,Hubei Province in the genus level.This indicates that the age of the fish-bearing strata in Wuhan is most likely to be the early Telychian rather than middle Telychian as previously assumed. 展开更多
关键词 Galeaspids Qingshui Formation lower Red Beds SILURIAN Jiangxi Province
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Lower risk of male infanticide in multilevel primate societies
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作者 Yi-Lin Xiang Yang Yu +1 位作者 Hui-Juan Pan Ming Li 《Zoological Research》 SCIE CAS CSCD 2023年第2期370-373,共4页
DEAR EDITOR,Male infanticide is considered a severe manifestation of sexual conflict in non-human primates during male takeover or male dominance changes. Males engaging in infanticide may obtain fitness benefits, but... DEAR EDITOR,Male infanticide is considered a severe manifestation of sexual conflict in non-human primates during male takeover or male dominance changes. Males engaging in infanticide may obtain fitness benefits, but at the cost of female reproductive outcomes. Consequently, females have developed various anti-infanticide counterstrategies, such as coalitions, dispersal. 展开更多
关键词 dispersal lower changes.
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Minimum-Time and Minimum-Jerk Gait Planning in Joint Space for Assistive Lower Limb Exoskeleton
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作者 Habib Mohamad Sadjaad Ozgoli Fadi Motawej 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第5期2164-2178,共15页
Assistive lower limb exoskeleton robot has been developed to help paraplegic patients walk again.A gait planning method of this robot must be able to plan a gait based on gait parameters,which can be changed during th... Assistive lower limb exoskeleton robot has been developed to help paraplegic patients walk again.A gait planning method of this robot must be able to plan a gait based on gait parameters,which can be changed during the stride according to human intention or walking conditions.The gait is usually planned in cartesian space,which has shortcomings such as singularities that may occur in inverse kinematics equations,and the angular velocity of the joints cannot be entered into the calculations.Therefore,it is vital to have a gait planning method in the joint space.In this paper,a minimum-time and minimum-jerk planner is proposed for the robot joints.To do so,a third-order system is defined,and the cost function is introduced to minimize the jerk of the joints throughout the stride.The minimum time required is calculated to keep the angular velocity trajectory within the range specified by the motor’s maximum speed.Boundary conditions of the joints are determined to secure backward balance and fulfill gait parameters.Finally,the proposed gait planning method is tested by its implementation on the Exoped®exoskeleton. 展开更多
关键词 Bionic robot Gait planning OPTIMIZATION Complete paraplegic lower limb exoskeleton
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A national survey of lower urinary tract symptoms in Jordan
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作者 Fadi Sawaqed Ibrahim Kharboush +3 位作者 Mohammed Suoub Ismail Albadawi Mohmmad Alhawatmeh Abdallah Murad 《Asian Journal of Urology》 CSCD 2023年第4期518-525,共8页
Objective To determine the prevalence of lower urinary tract symptoms(LUTS)and their severity population in Jordan.Methods This cross-sectional survey was conducted using a paper-based survey between August and Septem... Objective To determine the prevalence of lower urinary tract symptoms(LUTS)and their severity population in Jordan.Methods This cross-sectional survey was conducted using a paper-based survey between August and September in 2019.The study was carried out in the health care centers or hospitals in three different regions of Jordan:North(Irbid and Jarash),Middle(Amman,Madaba,Salt,and Zarqa),and South(Karak and Aqaba).Results To estimate the prevalence of LUTS,two definitions were used,including the first definition(presence of any LUTS regardless of the degree of severity)and the second definition(presence of any LUTS that occurs half the time or more).According to the first definition,1038(89.9%)reported LUTS(male:47.3%,female:52.7%),while 763(66.1%)reported LUTS according to the second definition(male:45.6%,female:54.4%).According to the International Prostate Symptom Score characterization,73.9%had nocturia and 62.9%reported daytime increased frequency.Conclusion LUTS are highly prevalent among the Jordanian population,and more than half of them have nocturia or daytime increased frequency as most frequently reported symptoms. 展开更多
关键词 lower urinary tract symptom VOIDING URGENCY NOCTURIA INCONTINENCE
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Combined load bearing capacity of rigid piles embedded in a crossanisotropic clay deposit using 3D finite element lower bound
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作者 Ardavan Izadi Reza Jamshidi Chenari 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2023年第3期717-737,共21页
In this study,an iterative-based three-dimensional finite element lower bound in association with the second-order cone programming method is adopted to evaluate the limit load of a single pile embedded in cross-aniso... In this study,an iterative-based three-dimensional finite element lower bound in association with the second-order cone programming method is adopted to evaluate the limit load of a single pile embedded in cross-anisotropic soils under general loading condition.The lower bound solutions of the pile embedded in an anisotropic soil deposit can be found by formulating the element equilibrium,equilibrium of shear and normal stresses along discontinuities,boundary conditions,yield function,and optimizing the objective function through the second-order cone programming method in conjunction with an iterative-based update procedure.A general loading condition is considered to profile the expansion of the safe load in the vertical-horizontal-moment(V-H-M)space.The results of this study are compared and validated against three different cases including an isotropic lateral loading,anisotropic end bearing capacity,and a pile embedded in an isotropic soil deposit under general loading condition.A parametric study is conducted to evaluate the impact of different influencing factors.It was found that the effect of anisotropy on the variation of lateral limit load of a single pile is more pronounced than the corresponding vertical and bending moment limit loads,whereas the interface properties have more significant effects on the vertical and bending moment limit loads in comparison to the lateral limit load. 展开更多
关键词 Rigid pile Cross-anisotropy CLAY Combined loading Three-dimensional finite element lower BOUND
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Systematic Review on Wearable Lower Extremity Robotic Exoskeletons for Assisted Locomotion
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作者 Shuang Qiu Zhongcai Pei +1 位作者 Chen Wang Zhiyong Tang 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第2期436-469,共34页
Lower extremity robotic exoskeletons(LEEX)can not only improve the ability of the human body but also provide healing treatment for people with lower extremity dysfunction.There are a wide range of application needs a... Lower extremity robotic exoskeletons(LEEX)can not only improve the ability of the human body but also provide healing treatment for people with lower extremity dysfunction.There are a wide range of application needs and development prospects in the military,industry,medical treatment,consumption and other felds,which has aroused widespread concern in society.This paper attempts to review LEEX technical development.First,the history of LEEX is briefy traced.Second,based on existing research,LEEX is classifed according to auxiliary body parts,structural forms,functions and felds,and typical LEEX prototypes and products are introduced.Then,the latest key technologies are analyzed and summarized,and the research contents,such as bionic structure and driving characteristics,human–robot interaction(HRI)and intentawareness,intelligent control strategy,and evaluation method of power-assisted walking efciency,are described in detail.Finally,existing LEEX problems and challenges are analyzed,a future development trend is proposed,and a multidisciplinary development direction of the key technology is provided. 展开更多
关键词 lower extremity robotic exoskeletons Bionic robot Classifcation method Human-robot interaction Biomechatronic
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Compliant Control of Lower Limb Rehabilitation Exoskeleton Robot Based on Flexible Transmission
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作者 Keping Liu Li Li +2 位作者 Wanting Li Jian Gu Zhongbo Sun 《Journal of Bionic Engineering》 SCIE EI CSCD 2023年第3期1021-1035,共15页
To ensure the safety, comfort, and effectiveness of lower limb rehabilitation exoskeleton robots in the rehabilitation training process, compliance is a prerequisite for human–machine interaction safety. First, under... To ensure the safety, comfort, and effectiveness of lower limb rehabilitation exoskeleton robots in the rehabilitation training process, compliance is a prerequisite for human–machine interaction safety. First, under the premise of considering the mechanical structure of the lower limb rehabilitation exoskeleton robot (LLRER), when conducting the dynamic transmission of the exoskeleton knee joint, the soft axis is added to ensure that the rotation motion and torque are flexibly transmitted to any position to achieve flexible force transmission. Second, to realize the active compliance control of LLRER, the sliding mode impedance closed-loop controller is developed based on the kinematics and dynamics model of LLRER, and the stability of the designed control system is verified by Lyapunov method. Then the experiment is designed to track the collected bicycle rehabilitation motion data stably, and the algorithm and dynamic model are verified to satisfy the experimental requirements. Finally, aiming at the transmission efficiency and response performance of the soft shaft in the torque transmission process of the knee joint, the soft shaft transmission performance test is carried out to test the soft shaft transmission performance and realize the compliance of the LLRER, so as to ensure that the rehabilitation training can be carried out in a safe and comfortable interactive environment. Through the design of rehabilitation exercise training, it is verified that the LLRER of flexible transmission under sliding mode impedance control has good adaptability in the actual environment, and can achieve accurate and flexible control. During the experiment, the effectiveness of monitoring rehabilitation training is brought through the respiratory belt. 展开更多
关键词 lower limb rehabilitation exoskeleton Flexible control Impedance control STABILITY
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