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Linking 24-h Movement Behavior Guidelines to Cognitive Difficulties,Internalizing and Externalizing Problems in Preterm Youth
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作者 Zhihui Cheng Ailikute Aikeremu +6 位作者 Yanping Gao Zhihao Zhang Anthony G.Delli Paoli Paolo Marcello Cunha Alyx Taylor Fabian Herold Liye Zou 《International Journal of Mental Health Promotion》 2024年第8期651-662,共12页
Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether ... Background:Given the heightened risk of developmental challenges associated with preterm birth,it is crucial to explore interventions that may ameliorate potential adverse outcomes.This study aimed to examine whether meeting the 24-h movement behavior(24-HMB)guidelines,which include recommendations on physical activity(PA),screen time(ST),and sleep(SL),is related to indicators of cognitive difficulties,internalizing problems(e.g.,depression and anxiety),and externalizing problems(e.g.,difficulties in making friends and arguing)in a sample of preterm youth(children and adolescents born preterm).Methods:In this cross-sectional study,data from 3410 preterm youth(aged 6 to 17 years)were included for data analyses.Multivariable logistic regression was used to investigate associations between meeting the 24-HMB guidelines and the above-mentioned health outcomes,while controlling for sociodemographic and health-related factors.Results:The prevalence of meeting 24-HMB guidelines varied across independent and integrated components of the 24-HMB guidelines.Meeting the ST guideline alone(p<0.05)and integrated guidelines(i.e.,ST+SL and ST+SL+PA)were associated with fewer cognitive difficulties and reduced internalizing and externalizing problems(p<0.05).Specifically,meeting the SL guideline alone and integrated guidelines(i.e.,SL+ST)were associated with lower odds of depression and anxiety(p<0.01).Additionally,meeting independent,and integrated(PA and/or ST)guidelines were associated with less pronounced difficulties in making friends and arguing(p<0.05).Meeting 24-HMB guidelines in an isolated and integrated manner are linked to better cognitive performance and fewer internalizing and externalizing problems in preterm youth.Conclusion:Results suggest that advocating for the implementation of the 24-HMB guidelines may reduce cognitive challenges and behavioral issues,which is of high relevance for improving public health.Future longitudinal studies in preterm youth should investigate how modifying specific 24-HMB behaviors,especially ST,influence cognitive difficulties,internalizing and externalizing problems in this vulnerable population. 展开更多
关键词 Cognitive difficulties externalizing problems internalizing problems physical activity preterm youth
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Evidence for the Reliability and Validity of the Arabic Version of the Student Risk Screening Scale for Internalizing and Externalizing Behaviors (SRSS-IE)
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作者 Sumayah A. Alrubayie Keetam D. F. Alkahtani 《Journal of Behavioral and Brain Science》 2024年第1期32-45,共14页
School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric proper... School-based universal screening for behavioral/emotional risk is a necessary first step to providing services in an educational setting for students with emotional and behavioral disorders (EBDs). Psychometric properties are critical to making decisions about choosing a screening instrument. The purpose of the present study was to examine the psychometric properties of the student risk screening scale for internalizing and externalizing behaviors (SRSS-IE). Participants included 3145 students and their teachers. Item-level analyses of the current sample supported the retention of all items. The internal consistency of the SRSS items ranged from 0.83 to 0.85. Convergent validity between the SRSS-IE and a well-established screening tool, the strength and difficulties questionnaire (SDQ), was found for the total score (r = 0.70). Additionally, the results of this study demonstrate strong social validity, suggesting the SRSS-IE to be a useful and functional screening tool. We conclude that the SRSS-IE is a valid and reliable instrument for assessing the level of emotional and behavioral difficulties among elementary students. 展开更多
关键词 the Student Risk Screening Scale for internalizing and externalizing Behaviors (SRSS-IE) Strength and Difficulties Questionnaire (SDQ) Emotional and Behavioral Difficulties Screening tools Systematic Screening
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Effect of external and internal cues on core muscle activation during the Sahrmann five-level core stability test
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作者 Skyla Stifter Jessie McCaffrey +2 位作者 Tyler Nichols Ayse Ozcan Edeer Justine Ward 《World Journal of Methodology》 2025年第1期95-104,共10页
BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of cor... BACKGROUND Pain in the back or pelvis or fear of back pain may affect the timing or cocontraction of the core muscles.In both static and dynamic movements,the Sahrmann core stability test provides an assessment of core muscle activation and a person's ability to stabilize the lumbopelvic complex.Preparatory cues and images can be used to increase the activation of these muscles.To attain optimal movement patterns,it will be necessary to determine what cueing will give the most effective results for core stability.AIM To investigate the effects of external and internal cues on core muscle activation during the Sahrmann five-level core stability test.METHODS Total 68 participants(21.83±3.47 years)were randomly allocated to an external(n=35)or internal cue group(n=33).Participants performed the Sahrmann fivelevel core stability test without a cue as baseline and the five-level stability exercises with an internal or external cue.External cue group received a pressure biofeedback unit(PBU),and the internal cue group received an audio cue.A Delsys Trigno^(TM)surface electromyography unit was used for muscle activation from the rectus abdominis,external oblique,and transverse abdominis/internal oblique muscles.RESULTS Linear mixed effects model analysis showed that cueing had a significant effect on core muscle activation(P=0.001);however,there was no significant difference between cue types(internal or external)(P=0.130).CONCLUSION Both external and internal cueing have significant effects on core muscle activation during the Sahrmann five-level core stability test and the PBU does not create higher muscle activation than internal cueing. 展开更多
关键词 external cue internal cue Muscle activation Core muscles Lumbopelvic stability Pressure biofeedback unit
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Internal fixator vs external fixator in the management of unstable pelvic ring injuries:A prospective comparative cohort study 被引量:1
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作者 Mohamed Abo-Elsoud Mostafa I Awad +2 位作者 Mahmoud Abdel Karim Sherif Khaled Mohamed Abdelmoneim 《World Journal of Orthopedics》 2023年第7期562-571,共10页
BACKGROUND Reconstruction of the pelvic ring anatomy in unstable anterior pelvic ring injuries is a significant step to reduce the mortality rate associated with these injuries efficiently.There is a debate on using e... BACKGROUND Reconstruction of the pelvic ring anatomy in unstable anterior pelvic ring injuries is a significant step to reduce the mortality rate associated with these injuries efficiently.There is a debate on using either an anterior subcutaneous pelvis internal fixator(INFIX)or an anterior supra-acetabular external fixator(EXFIX)to manage an unstable anterior pelvic ring fracture.AIM To compare the functional and radiological outcomes and complications of INFIX vs EXFIX in managing unstable pelvic ring injuries.METHODS A prospective cohort study included 54 patients with unstable pelvic ring fractures.The patients were divided into two groups;the INFIX group,in which 30 cases were fixed by INFIX,and the EXFIX group,in which 24 patients were treated by EXFIX.The average age in the EXFIX group was 31.17 years(16-57 years),while in the INFIX group,it was 34.5 years(17-53 years).The study included 20(66.7%)males and 10(33.3%)females in the INFIX group and 10(41.7%)males and 14(58.3%)females in the EXFIX group.The radiological outcomes were evaluated using Matta and Tornetta's score,and the functional outcomes using the Majeed score.RESULTS The results revealed a statistically significant difference between both groups(P=0.013)regarding radiological outcomes,according to Matta and Tornetta's score in favor of the INFIX group.Sitting,standing,and walking abilities were measured at a 3-mo follow-up visit using Majeed score modules.It was significantly better among the INFIX group than the EXFIX group in all three modules.At the final follow-up,both groups had no statistically significant difference according to the Majeed score;92.35 in the INFIX group and 90.99 in the EXFIX group(P=0.513).A lower surgical site infection rate was noticed in the INFIX group(P=0.007).CONCLUSION Anterior subcutaneous pelvis INFIX is associated with better radiological outcomes and a lower infection rate than anterior supra-acetabular EXFIX in managing patients with unstable anterior pelvic ring fractures. 展开更多
关键词 internal fixator external fixator UNSTABLE ANTERIOR PELVIC INJURIES
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Meta-analysis of the efficacy of volar plate internal fixation versus closed reduction and external fixation in the treatment of adult distal radius fractures
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作者 CHEN Jian-ge ZHANG Hai-ning +4 位作者 ZHAO Hong-zhou LIU Ming-jun XING Jia-hui WANG Ping WANG Wei-min 《Journal of Hainan Medical University》 CAS 2023年第19期44-56,共13页
Objective:To compare the efficacy of open reduction and volar locking plate internal fixation with closed reduction and external fixation in the treatment of distal radius fractures by using meta analysis.Methods:The ... Objective:To compare the efficacy of open reduction and volar locking plate internal fixation with closed reduction and external fixation in the treatment of distal radius fractures by using meta analysis.Methods:The databases of CNKI,Wanfang,Weipu,Chinese biomedical literature,Pubmed,Embase,and Cochrane Library were retrieved,and the randomized controlled studies that directly compared the efficacy of plate internal fixation and closed reduction external fixation in the treatment of distal radius fractures published publicly from the establishment of the database to April 2023 were collected.The two researchers independently screened the retrieved literature according to the inclusion and exclusion criteria,extracted data,used Cochrane risk bias assessment tool for quality assessment,and used RevMan 5.4 software for meta analysis.Results:A total of 10 randomized controlled trials were included,all of which were in English.There were 1042 patients in total,and 9 of them were rated as low risk.Meta analysis results showed that one year after the treatment of distal radius fracture with volar locking plate internal fixation,DASH score[MD=-5.64,95%CI(-7.21,-4.06),P<0.00001];One year later,PRWE score[MD=-5.90,95%CI(-8.88,-2.92),P=0.001];Palm flexion[MD=5.92,95%CI(1.29,10.55),P=0.01];Pronation[MD=2.48,95%CI(0.59,4.36),P=0.01];Postrotation[MD=4.73,95%CI(2.15,7.31),P=0.0003];Grip strength[MD=0.61,95%CI(0.12,1.10),P=0.02];palmar tilt angle[MD=9.84,95%CI(5.66,14.02),P<0.00001];Radial inclination[MD=4.33,95%CI(2.97,5.69),P<0.00001]was superior to closed reduction plaster or splint external fixation.One year later,the European Five dimensional Health Scale(EQ-5D-5L)score[MD=0.02,95%CI(-0.01,0.05),P=0.27];Back extension[MD=2.22,95%CI(-4.15,8.59),P=0.49];Ulnar deviation[MD=3.49,95%CI(-0.80,7.78),P=0.11];Radial deviation[MD=2.05,95%CI(-2.39,6.50),P=0.37];Ulnar variance[MD=-1.14,95%CI(-3.16,0.88),P=0.27];There was no significant difference in complications[MD=0.77,95%CI(0.54,1.10),P=0.16](P>0.05).Conclusion:Based on the current clinical data,internal fixation with volar locking plate is more conducive to mid-term DASH score and grip strength recovery than closed reduction plaster or splint external fixation,but there is no significant difference in the quality of life and complications of patients.For adult distal radius fractures,surgical indications should be carefully grasped,and non operative treatment should be given priority. 展开更多
关键词 Volar plate internal fixation Closed reduction external fixation PLASTER SPLINT Distal radius fracture Meta analysis
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Analysis of the Internal and External Factors Involved in Second Language Acquisition
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作者 蒲艳春 《科技信息》 2009年第20期I0079-I0080,共2页
Materialist dialectics holds that internal causes are the basis of change and the external causes are the condition of change, and that external causes become operative through internal causes. This law can be applied... Materialist dialectics holds that internal causes are the basis of change and the external causes are the condition of change, and that external causes become operative through internal causes. This law can be applied into SLA. The internal causes and external causes influence SLA greatly. This paper mainly discusses the factors involved in SLA process. 展开更多
关键词 唯物辩证法 历史 苏丹 英语 课外阅读
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Nonlinear Dynamic Analysis of Coupled Gear-Rotor-Bearing System with the Effect of Internal and External Excitations 被引量:11
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作者 ZHOU Shihua SONG Guiqiu +1 位作者 REN Zhaohui WEN Bangchun 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2016年第2期281-292,共12页
Extensive studies on nonlinear dynamics of gear systems with internal excitation or external excitation respectively have been carried out. However, the nonlinear characteristics of gear systems under combined interna... Extensive studies on nonlinear dynamics of gear systems with internal excitation or external excitation respectively have been carried out. However, the nonlinear characteristics of gear systems under combined internal and external excitations are scarcely investigated. An eight-degree-of-freedom(8-DOF) nonlinear spur gear-rotor-bearing model, which contains backlash, transmission error, eccentricity, gravity and input/output torque, is established, and the coupled lateral-torsional vibration characteristics are studied. Based on the equations of motion, the coupled spur gear-rotor-bearing system(SGRBS) is investigated using the Runge-Kutta numerical method, and the effects of rotational speed, error fluctuation and load fluctuation on the dynamic responses are explored. The results show that a diverse range of nonlinear dynamic characteristics such as periodic motion, quasi-periodic motion, chaotic behaviors and impacts exhibited in the system are strongly attributed to the interaction between internal and external excitations. Significantly, the changing rotational speed could effectively control the vibration of the system. Vibration level increases with the increasing error fluctuation. Whereas the load fluctuation has an influence on the nonlinear dynamic characteristics and the increasing excitation force amplitude makes the vibration amplitude increase, the chaotic motion may be restricted. The proposed model and numerical results can be used for diagnosis of faults and vibration control of practical SGRBS. 展开更多
关键词 spur gear-rotor-bearing system(SGRBS) backlash eccentricity internal and external excitations coupled lateral-torsional vibration
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EXTERNALIZATION AND INTERNALIZATION OF CARDIAC ENDOTHELIN RECEPTORS DURING DIFFERENT PHASES OF SEPSIS IN RAT 被引量:1
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作者 王晓红 杨军 +4 位作者 董林旺 庞永政 苏静怡 唐朝枢 刘乃奎 《Chinese Medical Sciences Journal》 CAS CSCD 2001年第1期10-14,共5页
To study the redistribution of endothelin- 1 (ET- 1) receptors in two subcellular organelles , the sarcolemmal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced... To study the redistribution of endothelin- 1 (ET- 1) receptors in two subcellular organelles , the sarcolemmal membrane and the light vesicle, of rat heart during the progression of sepsis. Methods. Sepsis was induced by cecal ligation and puncture (CLP). ET1 receptor was assayed by using [125I]- ET1 binding. Marker enzyme activities, protein yield, and dry- to- wet weight ratio of cardiac membranes were measured. Results. Septic rat heart exhibited two distinct phases: an initial hyperdynamic phase( 9h after CLP; early stage of sepsis) followed by a hypodynamic (18h after CLP, late stage of sepsis) phase. [125I]- ET1 binding study showed that during early stage of sepsis, the Bmax of ET1 receptors was increased by 30% in sarcolemma but decreased by 19% in light vesicles, while during late stage of sepsis, the Bmax was decreased by 24% in sarcolemma but increased by 38% in light vesicles.The total binding of sarcolemma and light vesicles was increased by 25% during early stage of sepsis but decreased by 17% during late stage of sepsis. Conclusions. These data indicated that ET1 receptors in the rat heart were externalized from light vesicles to sarcolemmal membranes during early hyperdynamic phase while internalized from surface membranes to intracellular compartment during late hypodynamic phase of sepsis. 展开更多
关键词 endothelial receptor SEPSIS externalIZATION internalIZATION
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The Internal and External Factors That Help to Push English into a Popular World Language
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作者 顾欢欢 《英语广场(学术研究)》 2012年第1期64-64,59,共2页
It is well known that English is the world language nowadays, and it is an official language in most countries. It is also currently the language most often taught as a foreign language. The reasons of the popularity ... It is well known that English is the world language nowadays, and it is an official language in most countries. It is also currently the language most often taught as a foreign language. The reasons of the popularity lie in both internal factors and external factors. In this paper, the author will analyze the factors that help to push English into a popular world language. 展开更多
关键词 world language official language internal factors external factors
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Exploring the Internal and External Factors that Influence Chinese EFL Students' Speaking Performance: A Case Study
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作者 陈思 《海外英语》 2017年第19期238-240,共3页
This case study on one Chinese EFL learner examined both the internal and external factors that affect Chinese EFL learner's speaking performance. Three interviews and three tests have been conducted in the whole ... This case study on one Chinese EFL learner examined both the internal and external factors that affect Chinese EFL learner's speaking performance. Three interviews and three tests have been conducted in the whole process, and the findings revealed:(1) interference from first language is the most influential factor that hinders speaking performance;(2) learner attitude significantly affects speaking performance;(3) learning strategies and practicing help improving performance. 展开更多
关键词 internal factors external factors EFL students speaking performance
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District Policy---Social Practice Through Internal and External Discourses: How the Implementation of a Single Regional Political Instrument Is Perceived, Understood and Communicated
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作者 Heidi Engesbak Christin Tcnseth 《Sociology Study》 2012年第1期68-82,共15页
This paper focuses on how the implementation of a single regional political instrument is perceived, understood and communicated. Designed as a regional political instrument, the Norwegian Ministry of Transport and Co... This paper focuses on how the implementation of a single regional political instrument is perceived, understood and communicated. Designed as a regional political instrument, the Norwegian Ministry of Transport and Communications started a pilot project: "Driver education as a part of upper secondary school in district Norway". The focal point in this paper is to explore how the professional participants understand and interpret the project as a regional political instrument in order to maintain the local community, identity and local belonging. The theoretical approach is based on Giddens's actor/structure theory, while the analysis based on discourse analysis, in the analysis we separated the arguments used in the professional discourse. We detected different categories of argument in the discourses among the professionals. In addition to the professional discourse, we became aware of a personal discourse. In both discourses the political instrument was perceived to be important in order to maintain the local community, create equality and maintain local identity and a sense of belonging. 展开更多
关键词 internal and external discourses local community and identity regional policy driver education
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The Internal and External Factors That Help to Push English into a Popular World Language
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作者 廖春玫 《海外英语》 2013年第24期221-223,共3页
At the present times, English is an important language tool for communication in the international affairs. More than two hundred years ago, to foresee the international economic and cultural life in the future, moder... At the present times, English is an important language tool for communication in the international affairs. More than two hundred years ago, to foresee the international economic and cultural life in the future, modern German philosopher Leibniz have insightfully pointed out that mutual exchanges among the countries need a universal language for communication. The Unit?ed States and Britain, on the other hand, have the dominant position in international affairs, which makes English become a domi?nant language in the world. This paper tries to figure out the internal and external factors that help to push English into a popular world language basing on the process of the English language's development. 展开更多
关键词 internal FACtoRS external FACtoRS world LANGUAGE
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Current status of laparoscopic and robotic ventral mesh rectopexy for external and internal rectal prolapse 被引量:21
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作者 Jan J van Iersel Tim JC Paulides +3 位作者 Paul M Verheijen John W Lumley Ivo AMJ Broeders Esther CJ Consten 《World Journal of Gastroenterology》 SCIE CAS 2016年第21期4977-4987,共11页
External and internal rectal prolapse with their affiliated rectocele and enterocele, are associated with debilitating symptoms such as obstructed defecation, pelvic pain and faecal incontinence. Since perineal proced... External and internal rectal prolapse with their affiliated rectocele and enterocele, are associated with debilitating symptoms such as obstructed defecation, pelvic pain and faecal incontinence. Since perineal procedures are associated with a higher recurrence rate, an abdominal approach is commonly preferred. Despite the description of greater than three hundred different procedures, thus far no clear superiority of one surgical technique has been demonstrated. Ventral mesh rectopexy(VMR) is a relatively new and promising technique to correct rectal prolapse. In contrast to the abdominal procedures of past decades, VMR avoids posterolateral rectal mobilisation and thereby minimizes the risk of postoperative constipation. Because of a perceived acceptable recurrence rate, good functional results and low mesh-related morbidity in the short to medium term, VMR has been popularized in the past decade. Laparoscopic or robotic-assisted VMR is now being progressively performed internationally and several articles and guidelines propose the procedure as the treatment of choice for rectal prolapse. In this article, an outline of the current status of laparoscopic and robotic ventral mesh rectopexy for the treatment of internal and external rectal prolapse is presented. 展开更多
关键词 Laparoscopic ventral mesh rectopexy Robot Rectal prolapse external rectal prolapse internal rectal prolapse RECtoCELE Mesh erosion Obstructed defecation Faecal incontinence Biological mesh
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An isopycnic-coordinate internal tide model and its application to the South China Sea 被引量:6
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作者 苗春葆 陈海波 吕咸青 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 2011年第6期1339-1356,共18页
A three-dimensional isopycnic-coordinate ocean model for the study of internal tides is presented. In this model, the ocean interior is viewed as a stack of isopycnic layers, each characterized by a constant density. ... A three-dimensional isopycnic-coordinate ocean model for the study of internal tides is presented. In this model, the ocean interior is viewed as a stack of isopycnic layers, each characterized by a constant density. The isopycnic coordinate performs well at tracking the depth variance of the thermocline, and is suitable for simulation of internal tides. This model consists of external and internal modes, and barotropic and baroclinic motions are calculated in the two modes, respectively. The capability of simulating internal tides was verified by comparing model results with an analytical solution. The model was then applied to the simulation of internal tides in the South China Sea (SCS) with the forcing of M2 and K1 tidal constituents. The results show that internal tides in the SCS are mainly generated in the Luzon Strait. The generated M2 internal tides propagate away in three different directions (branches). The branch with the widest tidal beam propagates eastward into the Pacific Ocean, the most energetic branch propagates westward toward Dongsha Island, and the least energetic branch propagates southwestward into the basin of the SCS. The generated KI internal tides propagate in two different directions (branches). One branch propagates eastward into the Pacific Ocean, and the other branch propagates southwestward into the SCS basin. The steepening process of internal tides due to shoaling effects is described briefly. Meridionally integrated westward energy fluxes into the SCS are comparable to the meridionally integrated eastward energy fluxes into the Pacific Ocean. 展开更多
关键词 internal tides isopycnic coordinate numerical simulation South China Sea (SCS)
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A STUDY ON THE CHARACTERISTICS OF INTERNAL ANDEXTERNAL WALL SURFACE TEMPERATUREIN THE URBAN AREA 被引量:2
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作者 何云玲 张一平 +4 位作者 刘玉洪 马友鑫 李佑荣 窦军霞 郭萍 《Journal of Tropical Meteorology》 SCIE 2004年第2期216-224,共9页
Internal and external wall surface temperatures (Tws) in April, August and December in Kunming, a city in low latitude plateau, were investigated. Results showed that the Tws in April were of the highest among the thr... Internal and external wall surface temperatures (Tws) in April, August and December in Kunming, a city in low latitude plateau, were investigated. Results showed that the Tws in April were of the highest among the three, followed by August and December. The Tws differences among walls with different orientation were higher in April and December when the weather tends to be sunny, and lower in August with more cloudy days in the time. In April and August, Tws of E-wall was the highest, followed by S- and N-wall. But in December Tws of S-wall might be sometimes higher than E one. Diurnal range of internal Tws was usually smaller than that of the external, with also a time lag for the occurrence of its maximum and minimum. The results can serve as a basis for further research on building microclimate and urban architecture designs. It also gives suggestions for similar studies in other areas. 展开更多
关键词 WALL internal and external surface surface temperature heat flux
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Natural radioactivity and the resulting radiation doses in some kinds of commercially marble collected from different quarries and factories in Egypt 被引量:2
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作者 S. Fares Ali.A.M. Yassene +2 位作者 A. Ashour M.K. Abu-Assy M .Abd El-Rahman 《Natural Science》 2011年第10期895-905,共11页
Fourteen samples of marble were collected from different factories in Egypt. The samples were crushed, dried in controlled furnace for around twenty four hours, and then stored for five weeks in plastic Marinelli beak... Fourteen samples of marble were collected from different factories in Egypt. The samples were crushed, dried in controlled furnace for around twenty four hours, and then stored for five weeks in plastic Marinelli beakers. Concentrations and the U- and Th-bearing minerals were studied by scanning electron microscopy (SEM) and energy dispersive X-ray spectrometry (EDS).The gamma radiation of the samples was measured, employing high resolution γ-ray spectroscopy with an accumulating time for about 80000 sec. each. From the measured γ -ray spectra, activity concentrations were determined for marble samples 226Ra (37. 6 ± 1.7 - 100.54 ± 3.2 Bq/kg), 232Th (3.57 ± 0.64 - 9.37 ± 1.80 Bq/kg) and 40K (30.68 ± 1.1 – 1196 ± 4.9 Bq/kg). The absorbed dose rates, annual effective dose rates, radium equivalent activities as well as the radiation hazard indices were estimated. The radium equivalent activities (Raeq) are lower than the limit of 370 Bq kg?1 set by the Organization for Economic Cooperation and Development (Exposure to radiation from the natural radioactivity in building materials. Report by a Group of Experts of the OECD, Nuclear Energy Agency, OECD, Paris, 1979) [1]. All obtained results referred to the fact that all the concentrations were within the allowed limits to domestic use. Comparing the results in this work with those published by International Atomic Energy Agency and local and universal researches, it was found that these concentrations were within the allowed limits for agricultural and domestic uses. 展开更多
关键词 MARBLE Effective Dose external and internal HAZARD Indexes NORMS Gamma SPECTROMETRY RADIUM Equivalent
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Influence of external circulation on sludge characteristics during start-up of internal circulation reactor 被引量:4
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作者 丁建南 王淀佐 《Journal of Central South University of Technology》 EI 2005年第4期425-429,共5页
The start-up of external circulationadded internal circulation(IC) reactor was finished in 26 d, 32 d fewer than that of IC reactor. To evaluate the influence of the added external circulation on the development of gr... The start-up of external circulationadded internal circulation(IC) reactor was finished in 26 d, 32 d fewer than that of IC reactor. To evaluate the influence of the added external circulation on the development of granular sludge, the characteristics of the granular sludge taken from the two tested laboratory-scale reactors during start-up were studied. The results show that the added external circulation can enhance biomass granulation, accelerate granule development and improve sludge characteristics. At the end of start-up, the granular size of sludge in external circulation-added IC reactor greatly increases with a size distribution much better than that of sludge in IC reactor. The granular sludge originated from external circulationadded IC reactor contains more extracellular polymers and has a greater settling velocity than that from IC reactor. Methanogenic activity of the granular sludge from the external circulationadded IC reactor started 26 d ago reaches 358.23mL·g -1 ·d -1 , 1.66 and 1.20 times as great as that of the sludge from the IC reactor started 26 d and 58 d ago respectively. 展开更多
关键词 external circulation internal circulation reactor characteristics of granular sludge
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Explore the Factors Hindering Women's Development from Various Dimensions
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作者 王文静 《海外英语》 2010年第5X期282-282,共1页
The objective of this paper is to pave the way for better development of women's roles in current society.As known to all,in all fields,politics,business or science,rarely there're women who make it to the top... The objective of this paper is to pave the way for better development of women's roles in current society.As known to all,in all fields,politics,business or science,rarely there're women who make it to the top.Subjectively,women themselves are to blame for their lack of confidence and perseverance.It's the internal and also significant reason.Objectively,gender discrimination should shoulder a substantial measure of responsibility.This point constitutes the external reason which cannot be overlooked. 展开更多
关键词 WOMEN development internal external
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Quasi-plane-hypothesis of strain coordination for RC beams seismically strengthened with externally-bonded or near-surface mounted fiber reinforced plastic 被引量:3
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作者 Ren Zhenhua Zeng Xiantao +1 位作者 Liu Hanlong Zhou Fengjun 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2013年第1期67-76,共10页
The application of fiber reinforced plastic(FRP),including carbon FRP and glass FRP,for structural repair and strengthening has grown due to their numerous advantages over conventional materials such as externally b... The application of fiber reinforced plastic(FRP),including carbon FRP and glass FRP,for structural repair and strengthening has grown due to their numerous advantages over conventional materials such as externally bonded reinforcement(EBR) and near-surface mounted(NSM) strengthening techniques.This paper summarizes the results from 21 reinforced concrete beams strengthened with different methods,including externally-bonded and near-surface mounted FRP,to study the strain coordination of the FRP and steel rebar of the RC beam.Since there is relative slipping between the RC beam and the FRP,the strain of the FRP and steel rebar of the RC beam satisfy the quasi-plane-hypothesis;that is,the strain of the longitudinal fiber that parallels the neutral axis of the plated beam within the scope of the effective height(h 0) of the cross section is in direct proportion to the distance from the fiber to the neutral axis.The strain of the FRP and steel rebar satisfies the equation:ε FRP =βε steel,and the value of β is equal to 1.1-1.3 according to the test results. 展开更多
关键词 strain coordination quasi-plane-hypothesis external-bonded near-surface mounted fiber reinforced plastic strengthening concrete beam
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Is the Long-term Economic Decline of the Philippines Unstoppable? Trends, Reasons, Outlook
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作者 Peter Richter 《Journal of Sustainable Business and Economics》 2023年第4期1-19,共19页
The Philippines was in the 1960s a model of development in Asia and second to Japan,but occupies presently only the 11th position under South-East and East Asian countries in terms of GDP-per capita.The article explor... The Philippines was in the 1960s a model of development in Asia and second to Japan,but occupies presently only the 11th position under South-East and East Asian countries in terms of GDP-per capita.The article explores why this important Asian country with a long colonial past and enormous economic potential still ranks under lower-income countries and has in the last decades let pass by many other Asian countries.In answering this question,the approach of external triggers for accelerated development is being applied.In stark contrast to the success stories of the strongly outward-looking Asian countries like the four Tigers,later of Thailand and Vietnam the Philippines never developed a vision of an open economy connecting pro-actively to the world markets.Trade is hampered by a non-competitive and highly protected national economy.The existing FDI is more oriented to the profitable local markets.Foreign debts were never effectively used and international tourism was never well promoted.Linking these failures to the existing power structures in the country,it seems very much that the backward forces like the big landowners,the local producers and industrialists never wanted and continue not to want to open up the economy to international competition and governments are complacent with these groups.Various indicators demonstrate the long-term decline of the Philippines:Among them the slow growth of the GDP and the continuously high poverty rates.As the alliance of big business and policy holds firm no change in the failing nationalistic economic model can be detected leaving the bleak outlook that the economic decline will continue. 展开更多
关键词 external triggers of accelerated development strategies Promotion of exports Protection of local industries Foreign direct investments Foreign indebting International tourism Concentration of the national economy Failures of the development model
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