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Text Difficulty,Working Memory Capacity and Mind Wandering During Chinese EFL Learners’Reading
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作者 Xianli GAO Li LI 《Chinese Journal of Applied Linguistics》 2024年第3期433-449,525,共18页
This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,m... This experimental study investigated how text difficulty and different working memory capacity(WMC)affected Chinese EFL learners’reading comprehension and their tendency to engage in task-unrelated thoughts,that is,mind wandering(MW),in the course of reading.Sixty first-year university non-English majors participated in the study.A two-factor mixed experimental design of 2(text difficulty:difficult and simple)×2(WMC:high/large and low/small)was employed.Results revealed that 1)the main and interaction effects of WMC and text difficulty on voluntary MW were significant,whereas those on involuntary MW were not;2)while reading the easy texts,the involuntary MW of high-WMC individuals was less frequent than that of low-WMC ones,whereas while reading the difficult ones,the direct relationship between WMC and involuntary MW was not found;and that 3)high-WMC individuals had a lower overall rate of MW and better reading performance than low-WMC individuals did,but with increasing text difficulty,their rates of overall MW and voluntary MW were getting higher and higher,and the reading performance was getting lower and lower.These results lend support to WM theory and have pedagogical implications for the instruction of L2 reading. 展开更多
关键词 text difficulty working memory capacity reading mind wandering voluntary mind wandering involuntary mind wandering reading comprehension
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Security analysis of satellite-to-ground reference-frame-independent quantum key distribution with beam wandering
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作者 周淳 赵燕美 +11 位作者 杨晓亮 陆宜飞 周雨 姜晓磊 汪海涛 汪洋 李家骥 江木生 汪翔 张海龙 李宏伟 鲍皖苏 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第8期192-201,共10页
The reference-frame-independent(RFI)quantum key distribution(QKD)is suitable for satellite-based links by removing the active alignment on the reference frames.However,how the beam wandering influences the performance... The reference-frame-independent(RFI)quantum key distribution(QKD)is suitable for satellite-based links by removing the active alignment on the reference frames.However,how the beam wandering influences the performance of RFI-QKD remains a pending issue in satellite-to-ground links.In this paper,based on the mathematical model for characterizing beam wandering,we present the security analysis for satellite-to-ground RFI-QKD and analytically derive formulas for calculating the secret key rate with beam wandering.Our simulation results show that the performance of RFI-QKD is better than the Bennett–Brassard 1984(BB84)QKD with beam wandering in asymptotic case.Furthermore,the degree of influences of beam wandering is specifically presented for satellite-to-ground RFI-QKD when statistical fluctuations are taken into account.Our work can provide theoretical support for the realization of RFI-QKD using satellite-to-ground links and have implications for the construction of large-scale satellite-based quantum networks. 展开更多
关键词 quantum key distribution satellite-to-ground beam wandering
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一种wandering B+tree问题解决方法 被引量:1
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作者 杨勇鹏 蒋德钧 《计算机研究与发展》 EI CSCD 北大核心 2023年第3期539-554,共16页
为了应对磁盘和固态硬盘随机写和顺序写性能差异较大的问题,文件系统和块存储系统通常采用日志结构(log-structured)技术将随机写转换为顺序写.因此,对于日志结构存储系统数据和元数据的修改都以异地写的方式执行.在日志结构存储系统中,... 为了应对磁盘和固态硬盘随机写和顺序写性能差异较大的问题,文件系统和块存储系统通常采用日志结构(log-structured)技术将随机写转换为顺序写.因此,对于日志结构存储系统数据和元数据的修改都以异地写的方式执行.在日志结构存储系统中,B+tree常被用于管理元数据,这就会导致wandering B+tree问题,即树结点异地更新会导致树结构递归更新.目前,现有工作主要通过分离树结点的逻辑索引和物理地址,并使用额外的数据结构和物理设备空间存放树结点逻辑索引和物理地址的映射,从而避免递归更新树结构.但现有方法既引入额外空间开销,又存在额外物理设备空间非顺序写的问题.提出IBT B+tree,将树结点逻辑索引和物理地址均存放在树结构中.同时,基于IBT B+tree结构引入dirty链表设计,并提出了非递归更新的IBT B+tree下刷算法.IBT B+tree既解决了wandering B+tree问题,又不引入额外的数据结构和物理设备空间,消除了固定物理设备空间的非顺序写.分别实现IBT B+tree和基于F2FS中NAT设计的B+tree,在此基础上设计实现Monty-Dev块存储系统以评价2棵B+tree.实验表明,在HDD和SSD介质上,IBT B+tree在写放大和下刷效率方面均优于NAT B+tree. 展开更多
关键词 日志结构存储系统 块存储系统 wandering B+tree IBT B+tree 写放大
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Wandering spleen torsion with portal vein thrombosis:A case report
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作者 Xin-Yan Zhu Dong-Xu Ji +2 位作者 Wen-Zai Shi Yu-Wei Fu Da-Kun Zhang 《World Journal of Clinical Cases》 SCIE 2023年第28期6955-6960,共6页
BACKGROUND Wandering spleen is rare clinically.It is characterized by displacement of the spleen in the abdominal and pelvic cavities and can have congenital or acquired causes.Wandering spleen involves serious compli... BACKGROUND Wandering spleen is rare clinically.It is characterized by displacement of the spleen in the abdominal and pelvic cavities and can have congenital or acquired causes.Wandering spleen involves serious complications,such as spleen torsion.The clinical symptoms range from asymptomatic abdominal mass to acute abdominal pain.Surgery is required after diagnosis.Cases of wandering spleen torsion with portal vein thrombosis(PVT)are rare.There is no report on how to eliminate PVT in such cases.CASE SUMMARY Ultrasound and computed tomography revealed a diagnosis of wandering spleen torsion with PVT in a 31-year-old woman with a history of childbirth 16 mo previously who received emergency treatment for upper abdominal pain.She recovered well after splenectomy and portal vein thrombectomy combined with continuous anticoagulation,and the PVT disappeared.CONCLUSION Rare and nonspecific conditions,such as wandering splenic torsion with PVT,must be diagnosed and treated early.Patients with complete splenic infarction require splenectomy.Anticoagulation therapy and individualized management for PVT is feasible. 展开更多
关键词 Portal vein thrombosis Splenic torsion wandering spleen Case report
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Wandering gravel-bed rivers and high-constructive stable channel sandy fluvial systems in the Ross River area,Yukon Territory,Canada 被引量:2
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作者 Darrel G.F.Long Grant W.Lowey 《Geoscience Frontiers》 SCIE CAS 2011年第3期277-288,共12页
Mid-Cretaceous strata within the Tintina Trench, 3 km west of the community of Ross River, contain evidence of deposition in two distinct, alternating, fluvial settings. Coal-bearing, mud-dominated strata are commonly... Mid-Cretaceous strata within the Tintina Trench, 3 km west of the community of Ross River, contain evidence of deposition in two distinct, alternating, fluvial settings. Coal-bearing, mud-dominated strata are commonly associated with high-constructive sandy channel systems, with extensive overbank, levee and splay deposits. Channels are between 3 and 30 m wide and 0.4-7 m thick. They show repetitive development of side and in-channel bar-forms, as well as up-channel widening of the rivers by selective erosion of associated overbank and levee deposits. Levees extended for several hundred metres away from the channels. In this setting low-angle inclined stratification and epsilon cross stratification may reflect lateral migration of crevasse channels or small streams. The paucity of exposure prevents recognition of the channels as products of multiple channel anastomosed systems or single channel high-constructive systems. Gravel-dominated strata, inter-bedded with, and overlying coal-bearing units, are interpreted as deposits of wandering gravel-bed rivers, with sinuosity approaching 1.4. In most exposures they appear to be dominated by massive and thin planar-bedded granule to small pebble conglomerates, which would traditionally be interpreted as sheet-flood or longitudinal bar deposits of a high-gradient braided stream or alluvial fan. Architectural analysis of exposures in an open-pit shows that the predominance of flat bedding is an artefact of the geometry of the roadside exposures. In the pit the conglomerates are dominated by large scale cross stratification on a scale of 1-5.5 m. These appear to have developed as downstream and lateral accretion elements on side-bars and on in-channel bars in water depths of 2-12 m. Stacking of strata on domed 3rd order surfaces suggests development of longitudinal in-channel bar complexes similar to those observed in parts of the modern Rhone River system. Mudstone preserved in some of the channels reflects intervals of channel abandonment or avulsion. Minimum channel width is from 70 to 450 m. 展开更多
关键词 Anastomosing rivers wandering gravel-bedrivers Fluvial architecture CRETACEOUS YUKON
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LIMITING DIRECTION AND BAKER WANDERING DOMAIN OF ENTIRE SOLUTIONS OF DIFFERENTIAL EQUATIONS 被引量:2
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作者 王珺 陈宗煊 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1331-1342,共12页
In this paper, we mainly investigate entire solutions of complex differential equations with coefficients involving exponential functions, and obtain the dynamical properties of the solutions, their derivatives and pr... In this paper, we mainly investigate entire solutions of complex differential equations with coefficients involving exponential functions, and obtain the dynamical properties of the solutions, their derivatives and primitives. With some conditions on coefficients, for the solutions, their derivatives and their primitives, we consider the common limiting directions of Julia set and the existence of Baker wandering domain. 展开更多
关键词 limiting direction Baker wandering domain entire function linear differential equation
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Pigment analysis of a color-leaf mutant in Wandering Jew (Tradescantia fluminensis) irradiated by carbon ions 被引量:4
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作者 HE Jinyu LU Dong +1 位作者 YU Lixia LI Wenjian 《Nuclear Science and Techniques》 SCIE CAS CSCD 2011年第2期77-83,共7页
Many mutants of plant induced by heavy ion beam irradiation have been reported in recent years,but leaf anthocyan mutants induced by ion irradiation in evergreen were rarely found.In this study,a color-leaf mutant wit... Many mutants of plant induced by heavy ion beam irradiation have been reported in recent years,but leaf anthocyan mutants induced by ion irradiation in evergreen were rarely found.In this study,a color-leaf mutant with purple leaves,stems and petals was isolated from clones of Wandering Jew irradiated by 95.8 MeV/u carbon ion beam.The concentration and histological distribution of leaf pigment were surveyed in wild type and mutant.In mutant,contents of total chlorophylls (Chl),chlorophyll a (Chl a),chlorophyll b (Chl b) and carotenoids (Car) decreased significantly,while concentration of the anthocyanins was 6.2-fold higher than that of wild type.Further composition analysis of anthocyanins by electrospray ionization mass spectrometry (ESI-MS) indicated that the purple pigmentation of leaves in mutant was caused by accumulation of petunidin anthocyanin.Microscopic examination showed that most petunidin anthocyanin accumulated in the lower epidermis,and little in vascular parenchyma of mutant,while there was no pigment in wild type.Meanwhile,in spongy parenchyma of mutant we observed little Chl,which the wild type abounds in.In conclusion,the color-leaf mutant of Wandering Jew induced by irradiation of carbon ions was improved in ornamental value,and it could be contribute to variation in level,component and distribution of foliar pigment.The possible mutation mechanisms were discussed. 展开更多
关键词 碳离子辐照 突变体 颜料分析 犹太人 叶绿素a 彩色 叶绿素B 色素沉着
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Transcendence and Wandering
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作者 杨云 袁英 《海外英语》 2012年第11X期202-203,共2页
Shen Congwen and Thomas Hardy are both known for their regional novels,Hardy for his "Wessex" novels,and Shen Congwen for his "World of Xiangxi" .Both writers display a sense of transcendence and w... Shen Congwen and Thomas Hardy are both known for their regional novels,Hardy for his "Wessex" novels,and Shen Congwen for his "World of Xiangxi" .Both writers display a sense of transcendence and wandering in their female characters.Both Xiao Xiao in Shen Congwen' s Xiao Xiao and Eustacia in Hardy' s The Return of the Native transcend the traditions and customs of their times,and experience a consequent wandering.But the ways of the two writers in presenting their heroines is quite different.While Xiao Xiao was mentally active but did nothing except follow the traditional system,Eustacia' s thought was followed by her own words and actions. 展开更多
关键词 EUSTACIA XIAO XIAO TRANSCENDENCE wandering
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A Stylistic Appreciation of Song for the Wandering Jew
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作者 仲夏仪 《英语广场(学术研究)》 2013年第7期58-60,共3页
As an important romantic poet,William Wordsworth produced large numbers of poems known for refined rhymes,images and thoughts,which are exemplified by Song for the Wandering Jew.This paper analyzes this poem by a styl... As an important romantic poet,William Wordsworth produced large numbers of poems known for refined rhymes,images and thoughts,which are exemplified by Song for the Wandering Jew.This paper analyzes this poem by a stylistic approach which shows how sounds,images and syntax artistically made contribution to the poetic quality. 展开更多
关键词 Stylistic analysis Song of the wandering Jew poem STANZA RHYME
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Wandering crowd simulation based on space syntax theory 被引量:3
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作者 ZHENG Liping SUN Chen LIU Li WANG Lin 《Computer Aided Drafting,Design and Manufacturing》 2012年第2期68-73,共6页
Space syntax has proven there appears to be a fundamental process that informs human and social usage of an environ- ment, and the effects of spatial configuration on movement patterns are consistent with a model of i... Space syntax has proven there appears to be a fundamental process that informs human and social usage of an environ- ment, and the effects of spatial configuration on movement patterns are consistent with a model of individual decision behavior. In- troducing space syntax to crowd simulation will enable space structure guide the random movement of the crowd with no specific targets. This paper proposes a simulation method of the wandering crowd, which calculates the crowd distribution corresponding to the space through space syntax and uses a hybrid path planning algorithm to dynamically navigate the crowd to conform to the dis- tribution. Experiments show the presented method can obtain reasonable and vision-realistic simulation results. 展开更多
关键词 space syntax crowd simulation wandering path planning
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Unusual association of Axenfeld-Rieger syndrome and wandering spleen:A case report 被引量:1
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作者 Yi-Lin Chang Joseph Lin +1 位作者 Yu-Hsien Li Lien-Cheng Tsao 《World Journal of Clinical Cases》 SCIE 2020年第8期1502-1506,共5页
BACKGROUND Axenfeld-Rieger syndrome(ARS)is an autosomal dominant genetic disease characterized by ocular developmental disorders and its association with torsion of wandering spleen(WS)has not been reported to date to... BACKGROUND Axenfeld-Rieger syndrome(ARS)is an autosomal dominant genetic disease characterized by ocular developmental disorders and its association with torsion of wandering spleen(WS)has not been reported to date to the best of our knowledge.This study aimed to describe a rare case of ARS observed at our emergency department.CASE SUMMARY A 25-year-old female presented with a constant lower abdominal pain of increasing severity.Diagnostic computed tomography with intravenous contrast material showed a non-homogenously enhanced splenic parenchyma with a twisted vascular pedicle.Further,an emergent laparoscopic exploration was performed,and an ischemic spleen without its normal ligamentous attachments was noted.Notably,the spleen did not regain its normal vascularity after detorsion;thus,we performed the laparoscopic total splenectomy.The postoperative course was uneventful,and the patient was discharged on the 5th postoperative day.This case demonstrates a rare association of WS and ARS.CONCLUSION Early diagnosis of WS in the emergency department is important to prevent pedicle torsion or splenic necrosis and to avoid splenectomy. 展开更多
关键词 wandering SPLEEN Axenfeld-Rieger SYNDROME Laparoscopic SPLENECTOMY Autosomal dominant ABDOMINAL pain Emergent surgery Case report
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STUDY ON THE MATHEMATICAL MODEL FOR DRILL WANDERING MOTION
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作者 Zhou Zhixiong Lin Cheng (College of Mechanical and Automotive Engineering, Hunan University) 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2000年第1期58-63,共6页
Based on the kinematic relationship of the drill, drill point and workpiece and the coordinate systems founded,the mathematical models of the drill point wandering motion for the drill initial penetration, i. e. the f... Based on the kinematic relationship of the drill, drill point and workpiece and the coordinate systems founded,the mathematical models of the drill point wandering motion for the drill initial penetration, i. e. the formulae for the drill point center locus, hole shape and cutting edge locus, are established. According to these formulae the hole shape to be made is simulated and analyzed. It is verified that the bending chatter of the drill during the drill penetrating is the main cause to form a polygon like hole. 展开更多
关键词 Drill point Initial penetration wandering motion Mathematical model
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WANDERING SUBSPACES OF THE HARDY-SOBOLEV SPACES OVER D^n
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作者 肖杰胜 曹广福 《Acta Mathematica Scientia》 SCIE CSCD 2016年第5期1467-1473,共7页
In this paper, we show that for log(2/3)/2log2≤ β ≤1/2, suppose S is an invariant subspace of the Hardy-Sobolev spaces H_β~2(D^n) for the n-tuple of multiplication operators(M_(z_1),...,M_(z_n)). If(M_(z_1)|S,...,... In this paper, we show that for log(2/3)/2log2≤ β ≤1/2, suppose S is an invariant subspace of the Hardy-Sobolev spaces H_β~2(D^n) for the n-tuple of multiplication operators(M_(z_1),...,M_(z_n)). If(M_(z_1)|S,..., M_(z_n)|S) is doubly commuting, then for any non-empty subset α = {α_1,..., α_k} of {1,..., n}, W_α~S is a generating wandering subspace for M_α|_S =(M_(z_(α_1))|_S,..., M_(z_(α_k))|_S), that is, [W_α~S]_(M_(α |S))= S, where W_α~S=■(S ■ z_(α_i)S). 展开更多
关键词 wandering subspace invariant subspace Beurling's theorem Hardy-Sobolev space doubly commuting
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Acute Volvulus of a Wandering Spleen on Pregnancy: A Case Report
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作者 Traoré Mamadou Kouakou Kouamé Bernadin +9 位作者 Anzoua Kouakou Ibrahim Menin Messou Benié Michelle Djahan Lydie Estelle Leh Bi Kalou Ismaêl N’Dri Ahou Bernadette Ekra Amos Serges Kouakou Blaise Amos Zouan Freddy Junior Lebeau Roger Diané Bamourou 《Open Journal of Obstetrics and Gynecology》 2018年第4期300-305,共6页
Wandering or ectopic spleen is a rare congenital or acquired abnormality due to a defect in the anatomical fixity of the spleen with the surrounding organs. Pedicle twisting is its most common complication. It is an a... Wandering or ectopic spleen is a rare congenital or acquired abnormality due to a defect in the anatomical fixity of the spleen with the surrounding organs. Pedicle twisting is its most common complication. It is an anatomo-clinical entity most often described in children, but rare in adults. It is a serious condition, especially when it occurs on a pregnancy putting at stake maternal and fetal prognosis. Authors report a case of acute volvulus of wandering spleen in a 26-year-old patient admitted for abdominal pain on an active pregnancy of 15 weeks of amenorrhea. Abdominal ultrasound scan helped to set the diagnosis. At laparotomy, the enlarged spleen was in an ectopic position, in the iliac fossa with a pedicle abnormally twisted in several spiral turns. Splenectomy was performed. The post-operative period was simple and the pregnancy progressed well to term. 展开更多
关键词 wandering SPLEEN VOLVULUS PREGNANCY SPLENECTOMY
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Detecting Dementia-Related Wandering Locomotion of Elders by Leveraging Active Infrared Sensors
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作者 Qiang Lin Weichao Zhao Weilan Wang 《Journal of Computer and Communications》 2018年第5期94-105,共12页
For elders with dementia, wandering is among the most problematic, frequent and dangerous behavior. Managing wandering behavior has become increasingly imperative due to its high prevalence, negative outcomes and burd... For elders with dementia, wandering is among the most problematic, frequent and dangerous behavior. Managing wandering behavior has become increasingly imperative due to its high prevalence, negative outcomes and burden on caregivers. We study to propose an active infrared-based method to identify wandering locomotion by monitoring rhythmical repetition of an elder’s indoor motion events. Specifically, we utilize our customized active infrared sensors to collect human indoor motions that will be converted into motion events by using hardware redundancy technique. Each motion event is a directed motion obtained via introducing temporal and dimensions into the spatial motion data. Based on the most cited spatial-temporal patterns of wandering locomotion, a spatiotemporal model is then proposed to identify wandering locomotion from an ongoing sequence of motion events. Experimental evaluation on eight individuals’ real-world motion datasets has shown that our proposed method is able to effectively identify wandering locomotion from repetitive events collected from active infrared sensors with a value over 98% for both accuracy and precision based on properly chosen parameters. Wandering in elders with dementia that follow specific spatiotemporal patterns can be reliably identified by analyzing repetitive motion events collected from active infrared sensors based on the well-known spatiotemporal patterns of wandering locomotion. 展开更多
关键词 wandering Locomotion ELDERS with DEMENTIA Active INFRARED SENSORS Assisted LIVING
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Wandering small intestinal stromal tumor:A case report
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作者 Jin-Zhan Su Shu-Feng Fan +2 位作者 Xia Song Lu-Jun Cao Dong-Ying Su 《World Journal of Clinical Cases》 SCIE 2022年第29期10622-10628,共7页
BACKGROUND The occurrence of gastrointestinal stromal tumors(GISTs)in the small intestine is rare,and a case of wandering small intestinal stromal tumor has been rarely reported to date.Dissemination of this case can ... BACKGROUND The occurrence of gastrointestinal stromal tumors(GISTs)in the small intestine is rare,and a case of wandering small intestinal stromal tumor has been rarely reported to date.Dissemination of this case can help inform future diagnosis and effective treatment.CASE SUMMARY A 68-year-old patient presented to us with tarry stools.Computed tomography showed a mobile tumor moving widely within the abdominal cavity.As the laboratory data showed a low range of red blood cells and an immediate surgery was not indicated,we performed digital subtraction angiography and embolization to achieve hemostasis.Surgical resection was performed after the patient’s condition improved.The tumor was successfully removed laparoscopically.Histological examination revealed submucosal GIST with infarction,which was of intermediate-risk,with mitotic count<1 per 10 high-power field.Immunohistochemical studies revealed the following:CD117+,Dog1+,CD34+,SMA+,S100-,CK-,Des-,SOX-11-,STAT6-,Ki67 Hotspots 10%+.The patient was ultimately diagnosed with wandering small intestinal stromal tumor.CONCLUSION When a highly vascularized tumor is clinically encountered in the small intestine,the possibility of stromal tumors should be considered.However,when the tumor cannot be visualized at its original location,the possibility of tumor migration is considered. 展开更多
关键词 wandering tumor Gastrointestinal stromal tumors Small intestine MELENA Gastrointestinal hemorrhage Case report
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Technology for Elderly with Memory Impairment and Wandering Risk
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作者 Sami Perala Kari Makela +1 位作者 Anna Salmenaho Rami Latvala 《E-Health Telecommunication Systems and Networks》 2013年第1期13-22,共10页
Objective:The main objective of this project was to studyhow to secure the wandering of elderly persons diagnosed with dementia caused by Alzheimer’s disease by using healthcare technologies. Methods:The study was ca... Objective:The main objective of this project was to studyhow to secure the wandering of elderly persons diagnosed with dementia caused by Alzheimer’s disease by using healthcare technologies. Methods:The study was carried out during a three-year period (2008-2011) in the region of South Ostrobothnia, Finland. Thirty-two elderly persons living at home and diagnosed with Alzheimer’s disease participated in the study. The ages of the intervention group ranged from 66 to 90 years;the average age was 81 years. A total of 63 different home care devices including 24 location based technologies were tested during the intervention.The choice of technology used was based on the individual needs of the elderly person. Results:Participants with mild stage memory impairment were able to use and benefit from the technology installed during the intervention to live more independently.The most useful devices were those that operated within the home. Nine of ten users of door alarm systems, five of nine users of GPS systems and all users of GSM systems were satisfied with the technologies. Conclusions:Location based alarm and access control technology can have a positive impact on the lives of elderly persons suffering from dementia. When chosen appropriately, technology can help to reduce or eliminate the wandering often associated with dementia.Regardless of the technology used, it should be installed when the elderly person is at the early stages of dementia;at later stages of the disease it is usually impossible for the elderly to adequately adopt the device. 展开更多
关键词 Healthcare Technology Home Care GERONTECHNOLOGY wandering DEMENTIA Alarm Systems
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NON-WANDERING SET OF A CONTINUOUS GRAPH MAP
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作者 GuRongbao SunTaixiang ZhengTingting 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2003年第4期477-481,共5页
The non-wandering set Ω(f) for a graph map f is investigated. It is showed that Ω(f) is contained in the closure of the set ER(f) of eventually recurrent points of f and ω-limit set ω(Ω(f)) of Ω(f) is containe... The non-wandering set Ω(f) for a graph map f is investigated. It is showed that Ω(f) is contained in the closure of the set ER(f) of eventually recurrent points of f and ω-limit set ω(Ω(f)) of Ω(f) is contained in the closure of the set R(f) of recurrent points of f. 展开更多
关键词 graph map recurrent point eventually recurrent point ω-limit set non-wandering set
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小浪底水库运行以来对黄河下游河道河床演变特性的影响 被引量:1
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作者 王远见 王强 +2 位作者 刘彦晖 刘刚 江恩慧 《水利学报》 EI CSCD 北大核心 2024年第5期505-515,共11页
小浪底水库自1999年10月下闸蓄水,23年来深刻改变了进入黄河下游河道的径流泥沙过程,进而引起了下游河道的再造床。本研究以1960—2022年长序列水文泥沙、断面地形、遥感影像等多源资料为基础,从径流泥沙、冲淤演变、形态调整三个方面... 小浪底水库自1999年10月下闸蓄水,23年来深刻改变了进入黄河下游河道的径流泥沙过程,进而引起了下游河道的再造床。本研究以1960—2022年长序列水文泥沙、断面地形、遥感影像等多源资料为基础,从径流泥沙、冲淤演变、形态调整三个方面阐明了小浪底水库运行以来对下游河道河床演变特性的影响。结果表明:(1)水库拦沙效果显著,下泄水量在年内分配更加均匀、沙量则向汛期更加集中;大流量和高含沙事件的严重程度和发生频率均有所降低;悬沙调整不明显,床沙粗化显著。(2)扭转了黄河下游河道持续淤积的趋势,冲淤调整主要发生在花园口至高村的游荡性河段;冲刷效率持续下降,主槽过流能力得到显著恢复。(3)游荡性河段横断面形态向窄深发展,二级悬河发育得到有效缓解,整体河势处于相对稳定状态。研究成果丰富了多沙河流修建水库对下游河道影响的科学认识,也可为小浪底水库优化调度提供科技支撑。 展开更多
关键词 径流泥沙 冲淤演变 形态特征 游荡性河段 黄河下游
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基于中华传统文化建构的新时代科幻电影叙事路径探究——以《流浪地球》系列为例 被引量:4
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作者 徐辰 《贵州大学学报(艺术版)》 2024年第2期17-25,共9页
2019年上映的《流浪地球》和2023年上映的《流浪地球2》开创了富有中国特色的新时代科幻电影叙事路径。在涉及人类生存环境的科幻灾难片中,《流浪地球》系列呈现出与西方同类科幻片截然不同的世界观、价值观和美学风格:家国大义高于个... 2019年上映的《流浪地球》和2023年上映的《流浪地球2》开创了富有中国特色的新时代科幻电影叙事路径。在涉及人类生存环境的科幻灾难片中,《流浪地球》系列呈现出与西方同类科幻片截然不同的世界观、价值观和美学风格:家国大义高于个人诉求、坚守家园与故土、重视家庭血缘和师徒传承、不同民族国家之间求同存异、强烈的现实关怀和鲜明的中国元素。《流浪地球》系列所传达的思想与文化内涵,是对中华传统文化的创造性转化,既有东方思维的烙印,又有鲜明的时代特色。 展开更多
关键词 科幻电影 流浪地球 中华传统文化 叙事路径
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