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Crohn’s disease of esophagus,stomach and duodenum 预览
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作者 Andréa Maia Pimentel Raquel Rocha Genoile Oliveira Santana 《世界胃肠药理与治疗学杂志:英文版(电子版)》 2019年第2期35-49,共15页
Crohn’s disease with involvement of the esophagus,stomach and duodenum has a prevalence of 0.5%to 4%in symptomatic adult patients,but some studies have shown that these results may be underestimated,since upper gastr... Crohn’s disease with involvement of the esophagus,stomach and duodenum has a prevalence of 0.5%to 4%in symptomatic adult patients,but some studies have shown that these results may be underestimated,since upper gastrointestinal endoscopy is not performed routinely in the initial evaluation of the disease in adult patients,as it is in the pediatric population.In general,involvement of the upper gastrointestinal tract in Crohn’s disease occurs concomitantly with involvement of the lower gastrointestinal tract.The diagnosis depends on clinical,endoscopic,histological and radiological evaluation.The presence of aphthoid ulcers,longitudinal ulcers,bamboo-joint-like appearance,stenoses and fistulas are endoscopic findings suggestive of the disease,and it is important to exclude the presence of Helicobacter pylori infection.The primary histological findings,which facilitate the diagnosis,are the presence of a chronic inflammatory process with a predominance of lymphoplasmacytic cells and active focal gastritis.The presence of epithelioid granuloma,although less frequent,is highly suggestive of the disease in the absence of chronic granulomatous disease.Treatment should include the use of proton pump inhibitors associated with corticosteroids,immunomodulators and biological therapy according to the severity of the disease. 展开更多
关键词 Crohn’s disease UPPER gastrointestinal tract UPPER digestive endoscopy ESOPHAGUS STOMACH DUODENUM Chronic GASTRITIS Focal GASTRITIS EPITHELIOID granuloma
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Successful endoscopic extraction of a proximal esophageal foreign body following accurate localization using endoscopic ultrasound:A case report 预览
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作者 Xiao-Ming Wang Shan Yu Xin Chen 《世界临床病例杂志》 2019年第10期1230-1233,共4页
BACKGROUND It is rare to find fish bones completely embedded in the wall of the esophagus with endoscopic findings similar to those of submucosal tumors.Most of the patients had the foreign body removed by thoracotomy... BACKGROUND It is rare to find fish bones completely embedded in the wall of the esophagus with endoscopic findings similar to those of submucosal tumors.Most of the patients had the foreign body removed by thoracotomy or thoracoscopy in the past,which resulted in great trauma.CASE SUMMARY We report a 58-year-old woman who experienced dysphagia for 6 d after eating fish.Cervical computed tomography(CT)and endoscopic ultrasonography(EUS)indicated a fish bone completely embedded in the wall of the esophagus with endoscopic findings similar to those of submucosal tumors.The results of CT reconstruction and EUS suggested that the fish bone was parallel to the longitudinal axis of the esophagus.We performed a longitudinal mucosal incision from the highest point of the uplift by using an Olympus dual knife to find the fish bone.Unfortunately,no fish bone was found,so we extended the incision and endoscopic submucosal dissection(ESD)technique was used to detect and remove the fish bone entirety.CONCLUSION The extraction of fish bone via ESD immediately after the injection of methylene blue into the submucous membrane under EUS guidance to obtain accurate localization of the foreign body may be the best treatment for such patients. 展开更多
关键词 Fish bone ENDOSCOPIC MUCOSAL DISSECTION Upper ESOPHAGEAL wall Case report
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应用上唇人中区皮瓣联合下唇Abbe瓣修复双侧唇裂继发鼻唇畸形 预览
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作者 林广民 游彩莲 +3 位作者 曹宁 郑美莲 汤逸颜 吴锦鸿 《中国整形与重建外科(英文)》 2019年第1期10-13,共4页
Objective To explore an ideal method for the correction of the secondary nasolabial deformities of bilateral cleft lip. Methods From January 2013 to December 2018 ,repairing nose and lip in median of the median upper ... Objective To explore an ideal method for the correction of the secondary nasolabial deformities of bilateral cleft lip. Methods From January 2013 to December 2018 ,repairing nose and lip in median of the median upper lip flap and lower lip Abbe flap in 13 patients with secondary nasolabial deformity of cleft lip, implanting artificial nose prosthesis when necessary. Results All the flaps were survived and nose appearance was greatly improved. The shape of the upper lip turned more similar to normal. Coordination between upper lip and lower lip was appropriate. Conclusion The median upper lip flap combined with lower lip Abbe flap to repair the secondary nasolabial deformities of bilateral cleft lip is effective . Goo d cosmetic results can be obtained. 展开更多
关键词 Bilateral CLEFT LIP Nasolabial DEFORMITY The median upper LIP FLAP Abbe FLAP
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Control factors of reservoir oil-bearing difference of Cretaceous Mishrif Formation in the H oilfield, Iraq 预览
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作者 ZHAO Limin ZHOU Wen +3 位作者 ZHONG Yuan GUO Rui JIN Zhimin CHEN Yantao 《石油勘探与开发:英文版》 2019年第2期314-323,共10页
To reveal the law of oiliness of the Upper Cretaceous carbonate reservoirs in the Middle East and factors controlling the oiliness, the Mishrif Formation of the H oilfield in Iraq was examined comprehensively. Based o... To reveal the law of oiliness of the Upper Cretaceous carbonate reservoirs in the Middle East and factors controlling the oiliness, the Mishrif Formation of the H oilfield in Iraq was examined comprehensively. Based on core observation and description, casting thin section analysis, and statistics of physical property and pore-throat structure parameter, etc., in combination with previous achievements and understanding, it is pointed out that the coring interval of Mishrif Formation has strong oiliness heterogeneity, and can be divided into 4 grades, oil rich, oil immersed, oil spot, and oil trace;the oil-bearing grade has obvious facies-controlled characteristic in macroscopic view;and in different oil-bearing grades, relatively oil-rich sections present higher karst development intensity, better physical properties and pore-throat structure characteristics. It is concluded through the study that the sedimentary microenvironment and eogenetic karstification determine the macroscopic oiliness of the reservoir in Mishrif Formation of H Oilfield, and the improvement of pore-throat structure caused by eogenetic karstification is the decisive factor of the micro oil-bearing difference of the reservoir. Finally,the genetic model of reservoir development and oil-bearing difference was established. 展开更多
关键词 carbonate RESERVOIRS eogenetic KARSTIFICATION RESERVOIR oiliness Mishrif FORMATION Upper CRETACEOUS Iraq
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Crude oil mobility and its controlling factors in tight sand reservoirs in northern Songliao Basin, East China 预览
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作者 FENG Jun ZHANG Bowei +9 位作者 FENG Zihui WANG Yachun ZHANG Juhe FU Xiaofei SUN Yonghe HUO Qiuli SHAO Hongmei ZENG Huasen QU Bin CHI Huanyuan 《石油勘探与开发:英文版》 2019年第2期324-334,共11页
Taking tight oil in Gaotaizi and Fuyu oil layers of the Upper Cretaceous Qingshankou Formation in northern Songliao Basin as an example, based on analyses of nuclear magnetic resonance and high pressure mercury inject... Taking tight oil in Gaotaizi and Fuyu oil layers of the Upper Cretaceous Qingshankou Formation in northern Songliao Basin as an example, based on analyses of nuclear magnetic resonance and high pressure mercury injection, experiment methods of supercritical carbon dioxide displacement and extraction are firstly employed to quantify crude oil mobility in tight sand reservoirs with different lithologies and oil contents. The results show that, under the conditions of simulating the Cretaceous Qingshankou Formation in the northern Songliao Basin at a temperature of 76-89 °C and a pressure of 35-42 MPa, the lower limit of the porosity of the movable oil is4.4%, and the lower limit of the permeability is 0.015′10^-3 mm^2. The lower limit of the average pore throat radius is 21 nm. On this basis,a classification standard for three types of tight sand reservoirs is proposed. Type I reservoirs are characterized by the movable fluid saturation larger than 40%, the movable oil ratio(ratio of movable oil to total oil) greater than 30% and the starting pressure gradient in the range of 0.3-0.6 MPa/m;Type II reservoirs are characterized by the movable fluid saturation in the range of 10%–40%, the movable oil ratio in the range of 5%–30% and the starting pressure gradient in the range of 0.6–1.0 MPa/m;Type III reservoirs are characterized by the movable fluid saturation less than 10% in general, the movable oil ratio less than 5%, and the starting pressure gradient greater than1.0 MPa/m. The fluid mobility in tight sand reservoirs is mainly affected by diagenesis and sedimentary environment. Reservoirs with depth lower than 2000 m are dominated by type I reservoir, whereas those with greater depth are dominated by type I and II reservoirs.Reservoirs in inner delta-front facies are dominated by type I reservoir, whereas those in outer delta-front facies and shore-shallow lacustrine facies are dominated by type II and III reservoirs. 展开更多
关键词 northern Songliao Basin TIGHT OIL pore structure crude OIL MOBILITY displacement experiment movable OIL ratio Upper Cretaceous Qingshankou Formation
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Fatal risk factors for cirrhosis complicated with the first upper gastrointestinal bleeding
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作者 Liu-Qing Wang Sheng-Nan Li Guo-Shun Zhang 《海南医科大学学报(英文版)》 2019年第6期51-54,共4页
Objective: To explore the fatal risk factors of liver cirrhosis complicated with the first upper gastrointestinal bleeding, so as to provide reference for clinical prevention and treatment. Methods: 572 patients with ... Objective: To explore the fatal risk factors of liver cirrhosis complicated with the first upper gastrointestinal bleeding, so as to provide reference for clinical prevention and treatment. Methods: 572 patients with cirrhosis admitted to North China University of Science and Technology and Tangshan Infectious Diseases Hospital from January 2014 to January 2018 were selected. According to whether there is concurrent upper gastrointestinal bleeding, it is divided into 163 cases of hemorrhage group and 409 cases of non-bleeding group. The patients in the hemorrhagic group were divided into case group (65 cases died of first upper gastrointestinal bleeding) and control group (98 cases died of non-first upper gastrointestinal bleeding). The general clinical data, laboratory and imaging data of the patients were analyzed. The risk factors of upper gastrointestinal bleeding in cirrhosis and the independent risk factors of the first upper gastrointestinal bleeding in cirrhosis were analyzed. Results: (1) Univariate analysis showed that: there were significant differences in Hb, PLT, CHE, ALB, TBIL, PT, left gastric vein diameter, portal vein diameter, course of cirrhosis, family history of cirrhosis, Child classification of liver function, esophagogastric varices, ascites, hepatic encephalopathy and portal vein thrombosis between hemorrhagic and non-hemorrhagic groups (P<0.05). The difference was statistically significant;(2) Multivariate logistic regression analysis showed that the diameter of left gastric vein, esophageal varices, ascites, Child C grade of liver function and portal vein thrombosis were risk factors for upper gastrointestinal bleeding in patients with cirrhosis. Left gastric vein diameter, esophagogastric varices and portal vein thrombosis are independent risk factors for first upper gastrointestinal bleeding in cirrhosis. Conclusion:Wider internal diameter of left gastric vein, severe esophagogastric varices and portal vein thrombosis are independent risk factors for fatal upper gastrointestinal bleed 展开更多
关键词 Liver CIRRHOSIS Upper GASTROINTESTINAL BLEEDING Risk factors.
精神分裂症伴下肢骨折非手术患者的护理研究
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作者 连云玲 辛翠玉 《双足与保健》 2019年第5期5-6,共2页
目的研究并探讨精神分裂症伴下肢骨折非手术患者的护理方法,并对其应用效果进行评价。方法将该院在2016年1月—2018年12月之间收治的110例精神分裂症伴下肢骨折非手术患者作为临床观察对象,随机分为两组。对照组患者予以常规护理措施,... 目的研究并探讨精神分裂症伴下肢骨折非手术患者的护理方法,并对其应用效果进行评价。方法将该院在2016年1月—2018年12月之间收治的110例精神分裂症伴下肢骨折非手术患者作为临床观察对象,随机分为两组。对照组患者予以常规护理措施,护理组患者予以康复护理措施,比较两组患者的护理效果。结果护理组患者精神病量表评分显著低于对照组,差异有统计学意义(P<0.05);护理组患者生活质量评分显著高于对照组,差异有统计学意义(P<0.05);护理组患者各项并发症发生率均显著低于对照组,差异有统计学意义(P<0.05)。结论精神分裂症伴下肢骨折非手术患者护理过程中,在常规基础护理方法上予以康复护理,可以有效提高患者生活质量,缓解患者临床症状,降低并发症发生率,值得在临床中推广。 展开更多
关键词 精神分裂症 下肢骨 护理方法
Direct visualizations of air flow in the human upper airway using in-vitro models
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作者 Haijun Wu Mengmeng Wang +3 位作者 Jianxia Wang Yunqiang An Hui Wang Yaqi Huang 《中国科学:生命科学英文版》 SCIE CAS CSCD 2019年第2期235-243,共9页
A better understanding of airflow characteristics in the upper airway(UA) is crucial in investigating obstructive sleep apnea(OSA), particle sedimentation, drug delivery, and many biomedical problems. Direct visualiza... A better understanding of airflow characteristics in the upper airway(UA) is crucial in investigating obstructive sleep apnea(OSA), particle sedimentation, drug delivery, and many biomedical problems. Direct visualization of air flow patterns in in-vitro models with realistic anatomical structures is a big challenge. In this study, we constructed unique half-side transparent physical models of normal UA based on realistic anatomical structures. A smoke-wire method was developed to visualize the air flow in UA models directly. The results revealed that the airflow through the pharynx was laminar but not turbulent under normal inspiration, which suggested that compared with turbulent models, a laminar model should be more suitable in numerical simulations. The flow predicted numerically using the laminar model was consistent with the observations in the physical models. The comparison of the velocity fields predicted numerically using the half-side and complete models confirmed that it was reasonable to investigate the flow behaviors in UA using the half-side model. Using the laminar model, we simulated the flow and evaluated the effects of UA narrowing caused by rostral fluid shift on pharyngeal resistance. The results suggested that fluid shift could play an important role in the formation of hypopnea or OSA during sleep. 展开更多
关键词 air FLOW VISUALIZATION UPPER AIRWAY model FLOW characteristic smoke-wire method FLOW simulation fluid SHIFT
Theoretical Analysis of Bearing Capacity of Shallowly Embeded Rectangular Footing of Marine Structures 预览
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作者 ZHANG Qiyi WU Shaoxuan +1 位作者 WU Liangpeng LIU Zhijie 《中国海洋大学学报:英文版》 SCIE CAS CSCD 2019年第1期123-132,共10页
In this paper,the finite element analysis software ABAQUS is used to analyze the ultimate bearing capacity of three-dimensional rectangular footing of marine structures.The deformation law and the failure mode of homo... In this paper,the finite element analysis software ABAQUS is used to analyze the ultimate bearing capacity of three-dimensional rectangular footing of marine structures.The deformation law and the failure mode of homogeneous seabed soil beneath the rectangular footing are analyzed in detail.According to the equivalent plastic strain of soil under rectangular footing,an allowable velocity field of homogeneous seabed soil is reasonably constructed.Based on the plastic limit analysis theory of soil mass and by using the Mohr-Coulomb yield criterion,an upper bound solution of the ultimate bearing capacity of three-dimensional rectangular footing on general homogeneous seabed soil is derived,and a correction factor of ultimate bearing capacity of three-dimensional rectangular footing is given.To verify the rationality and applicability of this theoretical solution,some numerical solutions are achieved using the general-purpose FEM analysis package ABAQUS,and comparisons are made among the derived upper bound solution,the solution of Vesic,and the solution of Salgado et al.The results indicate that the upper bound solution of the three-dimensional shallowly embedded rectangular footing proposed in this paper is accurate in calculating the bearing capacity of homogeneous seabed soil.For undrained saturated clay foundation and sandy foundation with smaller internal friction angle,this upper bound solution can evaluate the ultimate bearing capacity of rectangular footing;with the gradual increase of the internal friction angle of the soil,the ultimate bearing capacity of the proposed upper bound solution is slightly higher than that of the rectangular footing. 展开更多
关键词 upper BOUND analysis velocity field ULTIMATE bearing capacity RECTANGULAR FOOTING ABAQUS
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Water in the upper mantle and deep crust of eastern China: concentration, distribution and implications
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作者 Qun-Ke Xia Jia Liu +5 位作者 István Kovács Yan-Tao Hao Pei Li Xiao-Zhi Yang Huan Chen Ying-Ming Sheng 《国家科学评论:英文版》 CSCD 2019年第1期125-144,共20页
Understanding the concentration and distribution of water in the Earth’s mantle plays a substantial role in studying its chemical, physical and dynamic processes. After a decade of research, a comprehensive dataset o... Understanding the concentration and distribution of water in the Earth’s mantle plays a substantial role in studying its chemical, physical and dynamic processes. After a decade of research, a comprehensive dataset of water content in upper-mantle samples has been built for eastern China, which is now the only place with water-content data from such diverse types of natural samples, and provides an integrated picture of the water content and its distribution in the upper mantle at a continental scale. The main findings include the following:(i) the temporal heterogeneity of the water content in the lithospheric mantle from early Cretaceous(~120 Ma) to Cenozoic(<40 Ma) was tightly connected with the stability of the North China Craton(from its destruction to its consolidation);(ii) the heterogeneous water content in the Cenozoic lithospheric mantle beneath different blocks of eastern China was not only inherited from tectonic settings from which they came, but was also affected later by geological processes they experienced;(iii) the distinct water content between the lowermost crust and lithospheric mantle of eastern China and its induced rheological contrast at the base of the crust indicate that the continental crust–mantle boundary could behave either in a coupled or decoupled manner beneath different areas and/or at different stages;(iv) the alkali basalts of eastern China demonstrate a heterogeneous distribution of water content in the mantle;local and regional comparisons of the water content between the lithospheric mantle and basalts’ source indicate that the Cenozoic alkali basalts in eastern China were not sourced from the lithospheric mantle.Instead, the inferred high water contents in the mantle sources suggest that the Cenozoic eastern China basalts were likely sourced from the mantle transition zone(MTZ);and(v) both oceanic and continental crusts may carry a certain amount of water back into the deep mantle of eastern China by plate subduction.Such recycled crustal materials have not only crea 展开更多
关键词 WATER upper MANTLE and deep CRUST CONTINENTAL stability BASALT genesis eastern China
Asymptotic behavior for sums of non-identically distributed random variables 预览
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作者 YU Chang-jun CHENG Dong-ya 《高校应用数学学报:英文版(B辑)》 SCIE CSCD 2019年第1期45-54,共10页
For any given positive integer m,let Xi,1≤i≤m be m independent random variables with distributions Fi,1≤i≤m.When all the summands are nonnegative and at least one of them is heavy-tailed,we prove that the lower li... For any given positive integer m,let Xi,1≤i≤m be m independent random variables with distributions Fi,1≤i≤m.When all the summands are nonnegative and at least one of them is heavy-tailed,we prove that the lower limit of the ratio P(∑i=1^mXi>x)/∑i=1^mFi(x)equals 1 as x→∞.When the summands are real-valued,we also obtain some asymptotic results for the tail probability of the sums.Besides,a local version as well as a density version of the above results is also presented. 展开更多
关键词 lower limits UPPER limits heavy-tailed DISTRIBUTIONS local DISTRIBUTIONS DENSITIES
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Floristic Study of Vascular Plants in Typical Plant Communities in the Middle and Upper Reaches of the Yarlung Zangbo River 预览
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作者 GE Qingsong QU Xingle +2 位作者 LUO Daqing ZHENG Weilie FANG Jiangping 《景观研究:英文版》 2019年第5期123-129,134共8页
[Objective] Species composition and flora of vascular plants in the middle and upper reaches of the Yarlung Zangbo River were analyzed,to provide scientific basis for the estimation and protection of plant diversity,c... [Objective] Species composition and flora of vascular plants in the middle and upper reaches of the Yarlung Zangbo River were analyzed,to provide scientific basis for the estimation and protection of plant diversity,construction of ecological security shelter for the Tibetan Plateau.[Methods] In the middle and upper reaches of the Yarlung Zangbo River,quadrat (line transect) method was applied to investigate the phytocoenoses in sample plots,and relative literature was used to analyze the floristic composition and floristic element of vascular plants in the middle and upper reaches of the Yarlung Zangbo River.[Results]① There are 96 species (including subspecies and variations),69 genera of 35 vascular plant families,accounting for 16.83%,5.48%,1.66% and 11.63%,2.02%,0.31% of total vascular plant families,genera and species in Tibet and China.② There are 24 monotypic-genus families,accounting for 68.57% of the total family number in the local area;22 monotypic-species families,accounting for 62.86% of the total family number in the local area.Local flora shows the characteristics of ancient relict,such as Euphorbiaceae,Rubiaceae,Liliaceae and Ranunculaceae,they are all ancient primitive groups of the third flora and the fourth flora.③ Local vascular plant genera fall into 10 areal types and 8 variations.④ Temperate elements are much more than tropical elements,R/T is 0.19,indicating that vascular plants have typical temperate nature and residual tropical nature.There are only a few endemic genera,but more endemic species to the local area,and these species are closely related,of which there are some transitional species,indicating that local flora is too young to experience more differentiation and specialization.⑤ There are 24 Chinese endemic species,accounting for 25% of total number of species in the local area;among which there are 12 endemic species to Tibet,accounting for 50% of endemic species to China,12.5% of total number of species in the local area.Four key wild plant species are included in 展开更多
关键词 The middle and UPPER reaches of the Yarlung Zangbo RIVER TYPICAL plant community Vascular plants FLORA
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Using remotely sensed and climate data to predict the current and potential future geographic distribution of a bird at multiple scales:the case of Agelastes meleagrides,a western African forest endemic 预览
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作者 Benedictus Freeman Daniel Jiménez-García +1 位作者 Benjamin Barca Matthew Grainger 《鸟类学研究:英文版》 CSCD 2019年第3期262-270,共9页
Background:Understanding geographic distributions of species is a crucial step in spatial planning for biodiversity conservation, particularly as regards changes in response to global climate change.This information i... Background:Understanding geographic distributions of species is a crucial step in spatial planning for biodiversity conservation, particularly as regards changes in response to global climate change.This information is especially important for species of global conservation concern that are susceptible to the effects of habitat loss and climate change. In this study, we used ecological niche modeling to assess the current and future geographic distributional potential of White.breasted Guineafowl (Agelastes meleagrides)(Vulnerable) across West Africa. Methods:We used primary occurrence data obtained from the Global Biodiversity Information Facility and national parks in Liberia and Sierra Leone, and two independent environmental datasets (Moderate Resolution Imaging Spectroradiometer normalized difference vegetation index at 250 m spatial resolution, and Worldclim climate data at 2.5' spatial resolution for two representative concentration pathway emissions scenarios and 27 general circulation models for 2050) to build ecological niche models in Maxent. Results: From the projections, White.breasted Guineafowl showed a broader potential distribution across the region compared to the current IUCN range estimate for the species. Suitable areas were concentrated in the Gola rainforests in northwestern Liberia and southeastern Sierra Leone, the Tai.Sapo corridor in southeastern Liberia and southwestern Cote d'lvoire, and the Nimba Mountains in northern Liberia, southeastern Guinea, and northwestern Cote d'lvoire.Future climate.driven projections anticipated minimal range shifts in response to climate change. Conclusions: By combining remotely sensed data and climatic data, our results suggest that forest cover, rather than climate is the major driver of the species' current distribution. Thus, conservation efforts should prioritize forest protection and mitigation of other anthropogenic threats (e.g.hunting pressure) affecting the species. 展开更多
关键词 Climate change CONSERVATION CONSERVATION planning Ecological NICHE modeling Species distribution Upper GUINEA FOREST White-breasted Guineafowl
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The smoothed finite element method (S-FEM):A framework for the design of numerical models for desired solutions
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作者 Gui-Rong Liu 《结构与土木工程前沿:英文版》 EI CSCD 2019年第2期456-477,共22页
The smoothed finite element method (S-FEM) was originated by G R Liu by combining some meshfree techniques with the well-established standard finite element method (FEM). It has a family of models carefully designed w... The smoothed finite element method (S-FEM) was originated by G R Liu by combining some meshfree techniques with the well-established standard finite element method (FEM). It has a family of models carefully designed with innovative types of smoothing domains. These models are found having a number of important and theoretically profound properties. This article first provides a concise and easy-to-follow presentation of key formulations used in the S-FEM. A number of important properties and unique features of S-FEM models are discussed in detail, including 1) theoretically proven softening effects;2) upper-bound solutions;3) accurate solutions and higher convergence rates;4) insensitivity to mesh distortion;5) Jacobian?free;6) volumetric-locking-free;and most importantly 7) working well with triangular and tetrahedral meshes that can be automatically generated. The S-FEM is thus ideal for automation in computations and adaptive analyses, and hence has profound impact on Al-assisted modeling and simulation. Most importantly, one can now purposely design an S-FEM model to obtain solutions with special properties as wish, meaning that S-FEM offers a framework for design numerical models with desired properties. This novel concept of numerical model demand may drastically change the landscape of modeling and simulation. Future directions of research are also provided. 展开更多
关键词 computational METHOD FINITE ELEMENT METHOD smoothed FINITE ELEMENT METHOD strain SMOOTHING technique SMOOTHING domain weakened weak form solid mechanics SOFTENING effect upper bound solution
Kinematic improvement after the external-application herbs combine rehabilitation in upper-limb spasticity due to stroke 预览
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作者 Xiao Ding Zhen-Yao Wang +3 位作者 Hu Zhang Xin-wei Wang Wei-Hao Fang Da-Wei Zhan 《TMR非药物治疗》 2019年第2期48-54,共7页
Background: Spasm is one of the most serious physical impairment after stroke. the external-application herbs have showed some effects on the spasm. This study was conducted to evaluate the comparative effectiveness o... Background: Spasm is one of the most serious physical impairment after stroke. the external-application herbs have showed some effects on the spasm. This study was conducted to evaluate the comparative effectiveness of the external-application herbs and physical therapy in upper limb spasticity after stroke. Methods: A total of 100 patients with upper limb spasm after stroke (stroke time less than 1 month), have been recruited in Shun-yi Hospital of Beijing Traditional Chinese Medicine Hospital. Patients will be randomly allotted to one of two groups (N = 50, respectively): the TCM external application group, and the usual rehab (conventional physical therapy and medication treatment) group. The two groups will be administered once a month for three months. The primary outcome will be Modified Athworth Scale (MAS) and the simplified scale (Fugl-Meyer assessment, FMA) for upper limb. Results: Muscle tension and motor function were evaluated before and 4 weeks after treatments. There was a significant improvement in muscle tension and motor function in patients with stroke after the external-application herbs and physical therapy (P < 0.05). Conclusion: There was a significant improvement in kinematics in patients with stroke. 展开更多
关键词 EXTERNAL APPLICATION of Chinese HERBS TCM Anti-spastic Position UPPER LIMB
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Tail asymptotic for discounted aggregate claims with one-sided linear dependence and general investment return
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作者 Fenglong Guo Dingcheng Wang 《中国科学:数学英文版》 SCIE CSCD 2019年第4期735-750,共16页
In this study, we investigate the tail probability of the discounted aggregate claim sizes in a dependent risk model. In this model, the claim sizes are observed to follow a one-sided linear process with independent a... In this study, we investigate the tail probability of the discounted aggregate claim sizes in a dependent risk model. In this model, the claim sizes are observed to follow a one-sided linear process with independent and identically distributed innovations. Investment return is described as a general stochastic process with cadlag paths. In the case of heavy-tailed innovation distributions, we are able to derive some asymptotic estimates for tail probability and to provide some asymptotic upper bounds to improve the applicability of our study. 展开更多
关键词 POISSON risk model TAIL probability ONE-SIDED linear process heavy-tailed distribution ASYMPTOTIC upper BOUND investment RETURN
Quantitative analysis of planation surfaces of the upper Yangtze River in the Sichuan-Yunnan Region, Southwest China
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作者 Fenliang LIU Hongshan GAO +2 位作者 Baotian PAN Zongmeng LI Huai SU 《地球科学前沿:英文版》 SCIE CAS CSCD 2019年第1期55-74,共20页
Identification of the planation surfaces (PSs)is key for utilizing them as a reference in studying the long- term geomorphological evolution of the Upper Yangtze River Basin in the Sichuan-Yurman region,Southwest Chin... Identification of the planation surfaces (PSs)is key for utilizing them as a reference in studying the long- term geomorphological evolution of the Upper Yangtze River Basin in the Sichuan-Yurman region,Southwest China.Using a combined method of DEM-based fuzzy logic and topographic and fiver profiles analysis and based on a comprehensive analysis of four morphometfic parameters:slope,curvature,terrain raggedness index, and relative height,we established the relevant fuzzy membership functions,and then calculated the membership degree (MD)of the study area.Results show that patches with a MD>80% and an area>0.4 km^2 correspond well to the results of Google Earth and field investigation,representing the PS remnants.They consist of 1764 patches with an altitude,area,mean slope,and relief of mostly 2000-2500 m above sea level (asl),0-10 km^2,4°-9°,0-500 m,respectively,covering 9.2% of the study area's landscape,dipping to southeast,decreasing progressively from northwest to southeast in altitude,and with no clear relation between each patch's altitude and slope,or relief.All these results indicate that they are remnants of once regionally continuous PSs which were deformed by both the lower crust flow and the faults in upper crust,and dissected by the network of Upper Yangtze River.Additionally,topographic and river profiles analysis show that three PSs (PS1-PS3)well developed along the main valleys in the Yongren-Huili region, indicating several phases of uplift then planation during the Late Cenozoic era.Based on the incision amount deduced from projection of relict river profiles on PSs, together with erosion rates,breakup times of the PS 1,PS2,and PS3 were estimated to be 3.47 Ma,2.19 Ma,and 1.45 Ma,respectively,indicating appearance of modem Upper Yangtze River valley started between the Pliocene to early Pleistocene. 展开更多
关键词 planation surface fuzzy logic topographic ANALYSIS RIVER profile ANALYSIS Upper YANGTZE RIVER SOUTHWEST China
论低帮鞋中楦型结构与鞋靴款式设计之间的关系
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作者 潘美丽 费锐 《中国皮革》 CAS 2019年第2期61-65,共5页
鞋楦是鞋子设计与制作的依据,分别从长度、围度、线条以及凹凸度等方面细致全面地分析了鞋楦的结构特征,并选取了15码的婴童楦和36码的成人女楦作为试验对象,以数据对比的形式,详细分析了两款鞋楦的楦型结构与跟高、鞋头造型、帮面分割... 鞋楦是鞋子设计与制作的依据,分别从长度、围度、线条以及凹凸度等方面细致全面地分析了鞋楦的结构特征,并选取了15码的婴童楦和36码的成人女楦作为试验对象,以数据对比的形式,详细分析了两款鞋楦的楦型结构与跟高、鞋头造型、帮面分割、开关方式等之间的关系,为设计师提供理论支撑。 展开更多
关键词 鞋楦 脚长 跖围 鞋帮面 楦底样
Influence of non-dimensional strength parameters on the seismic stability of cracked slopes
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作者 ZHAO Lian-heng CHENG Xiao +1 位作者 LI De-jian ZHANG Ying-bin 《山地科学学报:英文版》 SCIE CSCD 2019年第1期153-167,共15页
Cracks in rock or soil slopes influence the stability and durability of the slopes.Seismic forces can trigger slope disasters,particularly in the cracked slopes.Considering the nonlinear characteristics of materials,t... Cracks in rock or soil slopes influence the stability and durability of the slopes.Seismic forces can trigger slope disasters,particularly in the cracked slopes.Considering the nonlinear characteristics of materials,the more generalized nonlinear failure criterion proposed by Baker is adopted.The influence of non-dimensional strength parameters on the stability of cracked slopes under earthquakes is performed using the upper bound limit analysis.The seismic displacement is calculated by adopting the logarithmic spiral failure surface according to the sliding rigid block model.Based on the existing studies,two methods for the stability analysis of cracked slopes under earthquakes are introduced:the pseudo-static method(with the factor of safety(Fs)as an evaluation index),and the displacement-based method(with the seismic displacement as an evaluation index).The pseudo-static method can only determine the instantaneous stability state of the cracked slope,yet the displacement-based methodreflects the stability variation of cracked slopes during earthquakes.The results indicate that the nondimensional strength parameters affect the factor of safety and seismic displacement of slopes significantly.The non-dimensional strength parameter(n)controlling the curvature of strength function shapes on the slope stability is affected by other parameters.Owing to cracks,the effect of non-dimensional strength parameters on seismic displacement becomes more significant. 展开更多
关键词 Cracked SLOPES Upper BOUND LIMIT analysis(UBLA) Generalized nonlinear failure CRITERION PSEUDO-STATIC METHOD Displacement-based METHOD
Upper cluster algebras and choice of ground ring
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作者 Eric Bucher John Machacek Michael Shapiro 《中国科学:数学英文版》 SCIE CSCD 2019年第7期1257-1266,共10页
We initiate a study of the dependence of the choice of ground ring on the problem on whether a cluster algebra is equal to its upper cluster algebra. A condition for when there is equality of the cluster algebra and u... We initiate a study of the dependence of the choice of ground ring on the problem on whether a cluster algebra is equal to its upper cluster algebra. A condition for when there is equality of the cluster algebra and upper cluster algebra is given by using a variation of Muller's theory of cluster localization. An explicit example exhibiting dependence on the ground ring is provided. We also present a maximal green sequence for this example. 展开更多
关键词 CLUSTER ALGEBRAS UPPER CLUSTER ALGEBRAS LOCALLY ACYCLIC CLUSTER ALGEBRAS
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