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Dependence of Lower Molding Temperature Limit and Molding Time on Molding Mechanism in Dental Thermoforming
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作者 Mutsumi Takahashi Masatoshi Takeuchi 《Materials Sciences and Applications》 2024年第9期350-357,共8页
Effectiveness and safety of a sports mouthguard depend on its thickness and material, and the thermoforming process affects these. The purpose of this study was to clarify the effects of differences in molding mechani... Effectiveness and safety of a sports mouthguard depend on its thickness and material, and the thermoforming process affects these. The purpose of this study was to clarify the effects of differences in molding mechanisms on the lower molding temperature limit and molding time in dental thermoforming. Ethylene vinyl acetate resin mouthguard sheet and two thermoforming machines;vacuum blower molding machine and vacuum ejector/pressure molding machine were used. The molding pressures for suction molding were −0.018 MPa for vacuum blower molding and −0.090 MPa for vacuum ejector molding, and for pressure molding was set to 0.090 MPa or 0.450 MPa. Based on the manufacturer’s standard molding temperature of 95˚C, the molding temperature was lowered in 2.5˚C increments to determine the lower molding temperature limit at which no molding defects occurred. In order to investigate the difference in molding time depending on the molding mechanism, the duration of molding pressure was adjusted in each molding machine, and the molding time required to obtain a sample without molding defects was measured. The molding time of each molding machine were compared using one-way analysis of variance. The lower molding temperature limit was 90.0˚C for the vacuum blower machine, 77.5˚C for the vacuum ejector machine, 77.5˚C for the pressure molding machine at 0.090 MPa, and 67.5˚C for the pressure molding machine at 0.45 MPa. The lower molding temperature limit was higher for lower absolute values of molding pressure. The molding time was shorter for pressure molding than for suction molding. Significant differences were observed between all conditions except between the pressure molding machine at 0.090 MPa and 0.45 MPa (P < 0.01). A comparison of the differences in lower molding temperature limit and molding time due to molding mechanisms in dental thermoforming revealed that the lower molding temperature limit depends on the molding pressure and that the molding time is longer for suction molding than for pressure molding. 展开更多
关键词 THERMOFORMING Suction Molding Pressure Molding lower Molding Temperature limit Molding Time
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Quantitative prediction model for the depth limit of oil accumulation in the deep carbonate rocks:A case study of Lower Ordovician in Tazhong area of Tarim Basin
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作者 Wen-Yang Wang Xiong-Qi Pang +3 位作者 Ya-Ping Wang Zhang-Xin Chen Fu-Jie Jiang Ying Chen 《Petroleum Science》 SCIE EI CAS CSCD 2024年第1期115-124,共10页
With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration field.Hence,the extent to which oil exploration can b... With continuous hydrocarbon exploration extending to deeper basins,the deepest industrial oil accumulation was discovered below 8,200 m,revealing a new exploration field.Hence,the extent to which oil exploration can be extended,and the prediction of the depth limit of oil accumulation(DLOA),are issues that have attracted significant attention in petroleum geology.Since it is difficult to characterize the evolution of the physical properties of the marine carbonate reservoir with burial depth,and the deepest drilling still cannot reach the DLOA.Hence,the DLOA cannot be predicted by directly establishing the relationship between the ratio of drilling to the dry layer and the depth.In this study,by establishing the relationships between the porosity and the depth and dry layer ratio of the carbonate reservoir,the relationships between the depth and dry layer ratio were obtained collectively.The depth corresponding to a dry layer ratio of 100%is the DLOA.Based on this,a quantitative prediction model for the DLOA was finally built.The results indicate that the porosity of the carbonate reservoir,Lower Ordovician in Tazhong area of Tarim Basin,tends to decrease with burial depth,and manifests as an overall low porosity reservoir in deep layer.The critical porosity of the DLOA was 1.8%,which is the critical geological condition corresponding to a 100%dry layer ratio encountered in the reservoir.The depth of the DLOA was 9,000 m.This study provides a new method for DLOA prediction that is beneficial for a deeper understanding of oil accumulation,and is of great importance for scientific guidance on deep oil drilling. 展开更多
关键词 Deep layer Tarim Basin Hydrocarbon accumulation Depth limit of oil accumulation Prediction model
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Different Deficit Irrigation Lower Limits and Irrigation Quotas Affect the Yield and Water Use Efficiency of Winter Wheat by Regulating Photosynthetic Characteristics
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作者 Huiqin Li Mingzhi Zhang +1 位作者 Na Xiao Haijian Yang 《Phyton-International Journal of Experimental Botany》 SCIE 2023年第12期3211-3236,共26页
To determine suitable thresholds for deficit irrigation of winter wheat in the well-irrigated area of the Huang-Huai-Hai Plain,we investigated the effects of different deficit irrigation lower limits and quotas on the... To determine suitable thresholds for deficit irrigation of winter wheat in the well-irrigated area of the Huang-Huai-Hai Plain,we investigated the effects of different deficit irrigation lower limits and quotas on the photosynthetic characteristics and grain yield of winter wheat.Four irrigation lower limits were set for initiating irrigation(i.e.,light drought(LD,50%,55%,60%and 50%of field holding capacity(FC)at the seedling-regreening,jointing,heading and filling-ripening stages,respectively),medium drought(MD,40%,50%,55%and 45%of FC at the same stages,respectively),adequate moisture(CK1,60%,65%,70%and 60%of FC at the same stages,respectively),heavy drought(CK2,35%,40%,45%and 40%of FC at the same stages,respectively))and five irrigation quota per event(30,60,90,120 and 180 mm)were set for each lower limit.We found that the increase of drought stress is conducive to normal photosynthesis of winter wheat leaves which is supported by the following findings.First,photosynthetic rate(Pn)of LD60 treatment was higher than that of LD30,LD90,LD120,LD180,MD30,MD60,MD90,MD120 and MD180.Then,Under the 90 mm irrigation quota treatment,the yield of winter wheat basically increased with the increase of irrigation’s lower limit.Moreover,With the increase in irrigation quota,the yield of winter wheat increased,and the water use efficiency(WUE)of winter wheat increased at first and then decreased.In addition,compared with the LD30,MD30,MD60,MD90,MD120,and MD180,the yield of winter wheat in LD60 treatment increased by about 3.23%(3-year average),32.3%,19.9%,11.7%,10.1%,and 14.6%.At the same time,the WUE with LD60 treatment of winter wheat was significantly higher than LD90,LD120,LD180,MD30,MD60,MD90,MD120,MD180 treatments.There was a positive correlation between soil volumetric water content and Pn and between yield and Pn.The key period for yield formation in winter wheat is 180 days after sowing.In conclusion,to achieve the dual goals of stable winter wheat yield and efficient utilization of water resources in this region,the suitable threshold for initiating deficit irrigation of winter wheat is the LD60 treatment.This conclusion provides data support for water-saving and stable yield of winter wheat in this area. 展开更多
关键词 Irrigation lower limit irrigation quota soil volume moisture content photosynthetic rate YIELD regression analysis
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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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Lateral earth pressure of granular backfills on retaining walls with expanded polystyrene geofoam inclusions under limited surcharge loading 被引量:1
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作者 Kewei Fan Guangqing Yang +2 位作者 Weilie Zou Zhong Han Yang Shen 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第4期1388-1397,共10页
Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,t... Existing studies have focused on the behavior of the retaining wall equipped with expanded polystyrene(EPS)geofoam inclusions under semi-infinite surcharge loading rather than limited surcharge loading.In this paper,the failure mode and the earth pressure acting on the rigid retaining wall with EPS geofoam inclusions and granular backfills(henceforth referred to as EPS-wall),under limited surcharge loading are investigated through two-and three-dimensional model tests.The testing results show that different from the sliding of almost all the backfill in the EPS-wall under semi-infinite surcharge loading,only an approximately triangular backfill slides in the wall under limited surcharge loading.The distribution of the lateral earth pressure on the EPS-wall under limited surcharge loading is non-linear,and the distribution changes from the increase of the wall depth to the decrease with the increase of the limited surcharge loading.An approach based on the force equilibrium of a differential element is developed to predict the lateral earth pressure behind the EPS-wall subjected to limited surcharge loading,and its performance was fully validated by the three-dimensional model tests. 展开更多
关键词 Retaining wall Expanded polystyrene(EPS)geofoam limited surcharge loading Lateral earth pressure Model test Prediction
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Performance Limits and Advancements in Single 2D Transition Metal Dichalcogenide Transistor
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作者 Jing Chen Ming-Yuan Sun +8 位作者 Zhen-Hua Wang Zheng Zhang Kai Zhang Shuai Wang Yu Zhang Xiaoming Wu Tian-Ling Ren Hong Liu Lin Han 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第12期134-188,共55页
Two-dimensional(2D)transition metal dichalcogenides(TMDs)allow for atomic-scale manipulation,challenging the conventional limitations of semiconductor materials.This capability may overcome the short-channel effect,sp... Two-dimensional(2D)transition metal dichalcogenides(TMDs)allow for atomic-scale manipulation,challenging the conventional limitations of semiconductor materials.This capability may overcome the short-channel effect,sparking significant advancements in electronic devices that utilize 2D TMDs.Exploring the dimension and performance limits of transistors based on 2D TMDs has gained substantial importance.This review provides a comprehensive investigation into these limits of the single 2D-TMD transistor.It delves into the impacts of miniaturization,including the reduction of channel length,gate length,source/drain contact length,and dielectric thickness on transistor operation and performance.In addition,this review provides a detailed analysis of performance parameters such as source/drain contact resistance,subthreshold swing,hysteresis loop,carrier mobility,on/off ratio,and the development of p-type and single logic transistors.This review details the two logical expressions of the single 2D-TMD logic transistor,including current and voltage.It also emphasizes the role of 2D TMD-based transistors as memory devices,focusing on enhancing memory operation speed,endurance,data retention,and extinction ratio,as well as reducing energy consumption in memory devices functioning as artificial synapses.This review demonstrates the two calculating methods for dynamic energy consumption of 2D synaptic devices.This review not only summarizes the current state of the art in this field but also highlights potential future research directions and applications.It underscores the anticipated challenges,opportunities,and potential solutions in navigating the dimension and performance boundaries of 2D transistors. 展开更多
关键词 Two-dimensional transistors Dimension limits Performance limits Memory devices Artificial synapses
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A Stroke-Limitation AMD Control System with Variable Gain and Limited Area for High-Rise Buildings
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作者 Zuo-Hua Li Qing-Gui Wu +1 位作者 Jun Teng Chao-Jun Chen 《Computer Modeling in Engineering & Sciences》 SCIE EI 2024年第1期865-884,共20页
Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a ... Collisions between a moving mass and an anti-collision device increase structural responses and threaten structural safety.An active mass damper(AMD)with stroke limitations is often used to avoid collisions.However,a strokelimited AMD control system with a fixed limited area shortens the available AMD stroke and leads to significant control power.To solve this problem,the design approach with variable gain and limited area(VGLA)is proposed in this study.First,the boundary of variable-limited areas is calculated based on the real-time status of the moving mass.The variable gain(VG)expression at the variable limited area is deduced by considering the saturation of AMD stroke.Then,numerical simulations of a stroke-limited AMD control system with VGLA are conducted on a high-rise building structure.These numerical simulations show that the proposed approach has superior strokelimitation performance compared with a stroke-limited AMD control system with a fixed limited area.Finally,the proposed approach is validated through experiments on a four-story steel frame. 展开更多
关键词 High-rise buildings active control stroke limitations variable gain variable limited area
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Supplementary Information to“Balancing the quantum speed limit and instantaneous energy cost in adiabatic quantum evolution”
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作者 徐建文 张宇佳 +9 位作者 郑文 蔡浩阳 周浩宇 李先科 廖绪东 张钰 李邵雄 兰栋 谭新生 于扬 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第4期13-18,共6页
I.SUPPLEMENTARY NOTE 1:THEORETICAL MATERIALS.The quantum speed limit(QSL)is essential for quantum computing and quantum communication,referring to the minimum time required for a quantum system to evolve from one stat... I.SUPPLEMENTARY NOTE 1:THEORETICAL MATERIALS.The quantum speed limit(QSL)is essential for quantum computing and quantum communication,referring to the minimum time required for a quantum system to evolve from one state to another.Two well-known forms of the QSL are the Mandelstam-Tamm(MT)relation TqsL≥πh/2△E[S1]and the Margolus-Levitin(ML)relation TqsL≥πh/2(E)[S2]where Tqst is denoted as the QSL time,h is the reduced Planck's constant,△E is the energy uncertainty(standard deviation)of the system,and(E)is the average energy of the system above its ground state.Both of relations provide a lower bound on the evolution time. 展开更多
关键词 QUANTUM limit SYSTEM
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Cosmology-Independent Photon Mass Limits from Localized Fast Radio Bursts by Using Artificial Neural Networks
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作者 冉景遇 王宝 魏俊杰 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期177-183,共7页
A hypothetical photon mass m_(γ) can produce a frequency-dependent vacuum dispersion of light, which leads to an additional time delay between photons with different frequencies when they propagate through a fixed di... A hypothetical photon mass m_(γ) can produce a frequency-dependent vacuum dispersion of light, which leads to an additional time delay between photons with different frequencies when they propagate through a fixed distance. The dispersion measure and redshift measurements of fast radio bursts(FRBs) have been widely used to constrain the rest mass of the photon. However, all current studies analyzed the effect of the frequency-dependent dispersion for massive photons in the standard ΛCDM cosmological context. In order to alleviate the circularity problem induced by the presumption of a specific cosmological model based on the fundamental postulate of the masslessness of photons, here we employ a new model-independent smoothing technique, artificial neural network(ANN), to reconstruct the Hubble parameter H(z) function from 34 cosmic-chronometer measurements.By combining observations of 32 well-localized FRBs and the H(z) function reconstructed by ANN, we obtain an upper limit of m_(γ) ≤ 3.5 × 10^(-51)kg, or equivalently m_(γ) ≤ 2.0 × 10^(-15)eV/c^(2)(m_(γ) ≤ 6.5 × 10^(-51)kg, or equivalently m_(γ) ≤ 3.6 × 10^(-15)eV/c_(2)) at the 1σ(2σ) confidence level. This is the first cosmology-independent photon mass limit derived from extragalactic sources. 展开更多
关键词 DISPERSION limit INDEPENDENT
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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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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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Speed limit effect during lane change in a two-lane lattice model under V2X environment
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作者 金灿 彭光含 聂方彦 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第3期718-722,共5页
Speed limit measures are ubiquitous due to the complexity of the road environment,which can be supplied with the help of vehicle to everything(V2X)communication technology.Therefore,the influence of speed limit on tra... Speed limit measures are ubiquitous due to the complexity of the road environment,which can be supplied with the help of vehicle to everything(V2X)communication technology.Therefore,the influence of speed limit on traffic system will be investigated to construct a two-lane lattice model accounting for the speed limit effect during the lane change process under V2X environment.Accordingly,the stability condition and the mKdV equation are closely associated with the speed limit effect through theory analysis.Moreover,the evolution of density and hysteresis loop is simulated to demonstrate the positive role of the speed limit effect on traffic stability in the cases of strong reaction intensity and high limited speed. 展开更多
关键词 traffic flow lattice model speed limit
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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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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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Proteomic response of Phaeocystis globosa to nitrogen limitation
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作者 Haisu LIU Ruiwang WEI +2 位作者 Qiangyong LEI Lei CUI Songhui LÜ 《Journal of Oceanology and Limnology》 SCIE CAS CSCD 2024年第1期141-149,共9页
Phaeocystis globosa is an important unicellular eukaryotic alga that can also form colonies.P.globosa can cause massive harmful algal blooms and plays an important role in the global carbon or sulfur cycling.Thus far,... Phaeocystis globosa is an important unicellular eukaryotic alga that can also form colonies.P.globosa can cause massive harmful algal blooms and plays an important role in the global carbon or sulfur cycling.Thus far,the ecophysiology of P.globosa has been investigated by numerous studies.However,the proteomic response of P.globosa to nitrogen depletion remains largely unknown.We compared four protein preparation methods of P.globosa for two-dimensional electrophoresis(2-DE)(Urea/Triton X-100 with trichloroacetic acid(TCA)/acetone precipitation;TCA/acetone precipitation;Radio Immuno Precipitation Assay(RIPA)with TCA/acetone precipitation;and Tris buffer).Results show that the combination of RIPA with TCA/acetone precipitation had a clear gel background and showed the best protein spot separation effect,based on which the proteomic response to nitrogen depletion was studied using 2-DE.In addition,we identified six differentially expressed proteins whose relative abundance increased or decreased more than 1.5-fold(P<0.05).Most proteins could not be identified,which might be attributed to the lack of genomic sequences of P.globosa.Under nitrogen limitation,replication protein-like,RNA ligase,and sn-glycerol-3-phosphate dehydrogenase were reduced,which may decrease the DNA replication level and ATP production in P.globosa cells.The increase of endonucleaseⅢand transcriptional regulator enzyme may affect the metabolic and antioxidant function of P.globosa cells and induce cell apoptosis.These findings provide a basis for further proteomic study of P.globosa and the optimization of protein preparation methods of marine microalgae. 展开更多
关键词 Phaeocystis globosa nitrogen limitation proteomic response two-dimensional electrophoresis
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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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Seismic-induced surficial failure of cohesive slopes using three-dimensional limit analysis:A case study of the Wangjiayan landslide in Beichuan, China
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作者 Gao Yufeng Liu Yang +1 位作者 Geng Weijuan Zhang Fei 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2024年第3期537-545,共9页
A seismic-induced landslide is a common geological catastrophe that occurs in nature.The Wangjiayan landslide,which was triggered by the Wenchuan earthquake,is a typical case in point.The Wanjiayan landslide caused ma... A seismic-induced landslide is a common geological catastrophe that occurs in nature.The Wangjiayan landslide,which was triggered by the Wenchuan earthquake,is a typical case in point.The Wanjiayan landslide caused many casualties and resulted in enormous property loss.This study constructs a simple surficial failure model based on the upper bound approach of three-dimensional(3D)limit analysis to evaluate the slope stability of the Wangjiayan case,while a traditional two-dimensional(2D)analysis is also conducted as a reference for comparison with the results of the 3D analysis.A quasi-static calculation is used to study the effect of the earthquake in terms of horizontal ground acceleration,while a parametric study is conducted to evaluate the critical cohesion of slopes.Rather than employing a 3D analysis,using the 2D analysis yields an underestimation regarding the safety factor.In the Wangjiayan landslide,the difference in the factors of safety between the 3D and 2D analyses can reach 20%.The sliding surface morphology as determined by the 3D method is similar to actual morphology,and the parameters of both are also compared to analyze the reliability of the proposed 3D method. 展开更多
关键词 LANDSLIDE Wenchuan earthquake surficial failure limit analysis stability QUASI-STATIC
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