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Effects of Extracurricular Physical Activity on the Physical Fitness Levels of Youngsters in School Environments 预览
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作者 Jéssica Barbosa Fernando Vieira Marta Sousa 《运动科学:英文版》 2019年第2期46-52,共7页
Extracurricular physical activity(EPA)complements the recommendations of daily physical activity and directly influences children’s physical fitness.The main objective of this study was to understand the effect of EP... Extracurricular physical activity(EPA)complements the recommendations of daily physical activity and directly influences children’s physical fitness.The main objective of this study was to understand the effect of EPA practice on students’physical fitness.It is a sample of 51 students of the fifth year schooling(62.7%girls and 37.3%boys)with an average of 10.2 years of age.It is an observational study,with two groups,one of non-participation in EPA=17 and the other of participation in EPA=34.Data collection was performed at a public school in the Lisbon area through the Fitnessgram Test Battery and a validated questionnaire for research purposes in order to understand the sociodemographic variables and practice of EPA.The cardiorespiratory variables,BMI and muscular strength were evaluated through specific tests of each physical capacity.The data were collected at the beginning and end of the school year.Between the two moments there were significant differences in all variables,assuming a non-significant value for the right inferior flexibility p=0.149.There was improvement in all variables except the BMI,which showed an increase at the end of the year,with a mean magnitude,ES=0.49. 展开更多
关键词 PHYSICAL FITNESS PHYSICAL activity PHYSICAL EDUCATION HEALTH and CHILDREN
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Effects of an Educational Program of Physical Exercise and Nutrition in Overweight or Obese Adults Suffering from Binge Eating Disorder 预览
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作者 A. Barroco D. Collado-Mateo +2 位作者 S. Villafaina J. Bravo J. A. Parraca 《食品科学与工程:英文版(2159-5828)》 2019年第3期88-94,共7页
Objective: To determine the effects of an educational program of exercise and nutrition in overweight or obese binge eating adults on body composition, physical fitness and biochemical parameters. Being educational, t... Objective: To determine the effects of an educational program of exercise and nutrition in overweight or obese binge eating adults on body composition, physical fitness and biochemical parameters. Being educational, the program also aimed to promote learning and self-control in the practice of physical activity and in the food choices of this population. Methodology: 40 patients overweight or obese binge eating adults aged between 30 and 60 years participated in the study. Participants were assigned to an experimental group (EG)(N = 23), to which the program was applied or a control group (CG)(N = 17). The study lasted eight months, where an initial and final evaluation was carried out, in order to verify the benefits obtained through this program. The program consisted of 47 one-hour, twice-a-week group practice sessions, one weekly self-help session, and three nutritional monitoring sessions throughout the program. Results: There were significant improvements in the experimental group in the body composition, namely in the percentage of fat mass, fat free mass, fat mass in the trunk, visceral index and metabolic age. In physical fitness, improvements were also seen in the experimental group, specifically in flexibility and handgrip strength. Conclusion: A multidisciplinary program involving regular physical exercise and nutritional educationled to achieve improvements in physical fitness and body composition in overweight and obese binge-eating disorder patients. 展开更多
关键词 PHYSICAL exercise NUTRITION obesity PHYSICAL fitness body composition food COMPULSION
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Application of Grey Correlation Analysis in Physical Fitness Assessment of Higher Vocational Students 预览
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作者 Lei Wang Yinan Chen +1 位作者 Shijie Cai Xia Liu 《国际计算机前沿大会会议论文集》 2019年第2期388-389,共2页
Taking students from Sanya Aviation and Tourism College as research objects, the relationship between physical course and physical health is discussed with the method of grey relational analysis. The index with the hi... Taking students from Sanya Aviation and Tourism College as research objects, the relationship between physical course and physical health is discussed with the method of grey relational analysis. The index with the highest degree of correlation between female students and teaching assessment was the index related to the physical core competence exercise, while the indexes with the highest degree of correlation between male students and teaching assessment were the indexes related to the maintenance of strong and healthy body shape and physical core competence. Thus, in the physical education course setting of higher vocational colleges and in the process of the integrated development between their teaching and students’ physical health, their teaching mode should aim at students’ exercise needs and promoting the quality improvement of their physical education teaching. 展开更多
关键词 GREY system theory PHYSICAL EDUCATION TEACHING PHYSICAL HEALTH ASSESSMENT
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Chris Barker’s Biological and Cultural Research in Development Theories of Physical Culture at Vietnam(In the Case of Nam Huynh Dao School) 预览
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作者 Huynh Quoc Thang 《国际关系与外交:英文版》 2019年第8期370-376,共7页
In relation to human issues,the relationship between biology and culture has long been an important part of general social science research,cultural studies in particular.In which Chris Barker’s theory of biology and... In relation to human issues,the relationship between biology and culture has long been an important part of general social science research,cultural studies in particular.In which Chris Barker’s theory of biology and culture in relation to related theories can be considered as one of the noteworthy remarks about the method and methodology to pass on the actual field Nam Huynh Dao school,the article focuses on clarifying the basic content of the problem with orientation to contribute to research and development of physical culture in Vietnam at present.This article was selected to read and print in the conference proceedings of scientific conference entitled“Theory of Western Culture and Applied to Vietnamese Culture Research”organized by the University of Social Sciences and Humanities,Vietnam National University-HCM City(USSH,VNU-HCM,Vietnam)(29 November 2018). 展开更多
关键词 biology and CULTURE PHYSICAL CULTURE RESEARCH to develop PHYSICAL CULTURE SCHOOL of NAM Huynh DAO
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Associations between the physical environment and park-based physical activity:A systematic review
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作者 Ru Zhang Hagen Wulff +1 位作者 Yanping Duan Petra Wagner 《运动与健康科学:英文版》 SCIE 2019年第5期412-421,共10页
Background:With an increase in the evidence for the associations between park-based physical activity(PA)and physical environments(especially park and neighborhood environments),researchers face an important challenge... Background:With an increase in the evidence for the associations between park-based physical activity(PA)and physical environments(especially park and neighborhood environments),researchers face an important challenge in interpreting and summarizing the evidence to develop environ?mental change interventions.An updated review is needed to better inform policymaking and environmental interventions.The current study aimed to systematically review the research on the associations of park-based PA with park and neighborhood environmental characteristics.Methods:We targeted English peer-reviewed articles from 5 electronic databases using keywords related to park-based PA,park environments,and neighborhood environments.Of the 4071 identified papers,25 studies published between 2008 and 2016 met all the eligibility criteria and were included in this review.Results:The characteristics of physical environment that received consistent support included paths/trails,lighting,and incivilities(e.g.,broken glasses and litter).Mixed findings were revealed for 6 park environmental factors(unspecified active facilities,playgrounds and skating areas,fit?ness stations,picnic areas,greenness,and park size)and 2 neighborhood environmental factors(park density and park proximity).Conclusion:It can be concluded that paths/trails,lighting,and incivilities are 3 key physical environmental attributes of park-based PA.Given the inconsistent findings on park and neighborhood environmental factors,more robust designs such as prospective investigation are required. 展开更多
关键词 Neighborhood Park-based PHYSICAL activity PARK ENVIRONMENT PHYSICAL ENVIRONMENT Systematic review
Cold contact urticaria combined with cold-dependent dermographism and serum autoreactivity: what have we ignored?
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作者 Qi-Quan Chen Hua Zhong +1 位作者 Zhi-Qiang Zhong Fei Hao 《国际皮肤性病学杂志(英文)》 2019年第1期43-44,共2页
Introduction Urticaria is a common disease in dermatology.Physical urticarias are a group of urticaria that are induced by various physical stimulations,including shear force,cold,heat,pressure,and solar and vibratory... Introduction Urticaria is a common disease in dermatology.Physical urticarias are a group of urticaria that are induced by various physical stimulations,including shear force,cold,heat,pressure,and solar and vibratory stimulations.Cold contact urticaria (CCU),the second most common subtype among all physical urticarias in China,is characterized by itchy wheals and edema on skin following exposure to cold.The ice cube skin contact test is one of the most used methods by which to make the diagnosis of CCU[1]. 展开更多
关键词 PHYSICAL stimulations PHYSICAL urticarias Introduction
The relationship between transport-to-school habits and physical activity in a sample of New Zealand adolescents
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作者 Chiew Ching Kek Enrique García Bengoechea +1 位作者 John C.Spence Sandra Mandic 《运动与健康科学:英文版》 SCIE 2019年第5期463-470,共8页
Objectives:Adolescents using active transport(AT)to school have higher levels of physical activity(PA)compared with motorized transport(MT)users.This study compared school day and weekend day PA in adolescents using A... Objectives:Adolescents using active transport(AT)to school have higher levels of physical activity(PA)compared with motorized transport(MT)users.This study compared school day and weekend day PA in adolescents using AT,MT,or combined AT and MT(AT + MT)to travel to school.Methods:Adolescents(n= 314;age:14.7±1.4 years;32.8% boys)from Dunedin(New Zealand)wore an accelerometer for 7 days and completed a self-reported survey regarding mode of transport to school(73 AT,56 AT + MT,and 185 MT).Data were analyzed using t tests,analysis of variance,and χ2 tests.Results:Although the proportion of adolescents meeting PA guidelines significantly differed among transport groups(AT,47.9%;AT + MT,46.4%;MT,33.5%;p=0.048;overall,39.2%),the observed differences were due mainly to girls.Compared with MT,AT and AT+MT engaged in more moderate-to-vigorous PA(MVPA)per day(AT:61.2 ± 23.2 min;AT+MT:59.6 ± 21.7 min;MT:52.5 ± 19.6 min;p = 0.004;p<0.001,adjusted for gender),per school day and before school.Immediately after school(15:00-16:00),AT engaged in significantly more MVPA compared with AT + MT and MT.No differences in MVPA between the groups were observed in the late afternoon/early evening period during school days or on weekend days.Conclusion:Compared with MT users,adolescent girls using AT or AT + MT accumulated more MVPA during school commute time.AT + MT to school is also a plausible way to increase adolescent girls’ PA when AT only is not feasible. 展开更多
关键词 ACCELEROMETER ADOLESCENT Physical activity SCHOOLS Transportation WALKING
Kinesio tape in the treatment of postoperative lymphedema of breast cancer 预览
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作者 Fu-Yu Leng Zhu Yang +3 位作者 Feng-Xi Long Li Luo Wen-Yu Wu Dong-Xin Tang 《TMR非药物治疗》 2019年第2期36-41,共6页
The Kinesio tape was originally developed by Dr. Kenzo Kase, a Japanese chiropractor, which was used for pain of joint and muscle, the elastic tape is capable of stretching up to 130-140% of its resting static length ... The Kinesio tape was originally developed by Dr. Kenzo Kase, a Japanese chiropractor, which was used for pain of joint and muscle, the elastic tape is capable of stretching up to 130-140% of its resting static length ensuring free mobility of the applied muscle or joint. It is claimed that Kinesio tape supports injured muscles and joints and helps relieve pain by lifting the skin and allowing improved blood and lymph flow. Therefore, Kinesio Taping has become a very popular treatment for several health conditions over the last decade. Nowadays, lymphatic drainage is a new function of Kinesio taping in the field of physical therapy. This article explores the application of Kinesio tape in breast cancer-related lymphedema in order to provide a new treatment for patients with lymphedema after breast cancer surgery. 展开更多
关键词 Kinesio TAPE BREAST cancer LYMPHEDEMA PHYSICAL therapy
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Interpretation of Jadine's Identity Cognition inTar Babyfrom thePerspective of Space Theory 预览
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作者 WANG Ruofan 《国际英语教育研究:英文版》 2019年第1期43-45,共3页
According to the contemporary Western theory of Lefebvre, the space is divided into three levels: physical space, spiritual space and social space. After going through the toss of the physical space, the exile of the ... According to the contemporary Western theory of Lefebvre, the space is divided into three levels: physical space, spiritual space and social space. After going through the toss of the physical space, the exile of the spiritual spaceas well as the dilemma of social space with the journey from Paris to Isle des Chevaliers, to New York, then to Eloe, and finally to Paris, Jadine in Tar Baby had broken the restriction of "dualism" andobtained the ethical identity and culture affiliation of ,"black&white", which will create a new path for the whole African-Americans to search for their ethnic identities and culture attributions. 展开更多
关键词 physical SPACE SPIRITUAL SPACE SOCIAL SPACE IDENTITY exploration culture affiliation
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Interrelationship between soil depth and soil properties of Pieniny National Park forest(Poland)
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作者 Justyna SOKOLOWSKA Agnieszka jOZEFOWSKA +1 位作者 Karolina WOZNICA Tomasz ZALESKI 《山地科学学报:英文版》 SCIE CSCD 2019年第7期1534-1545,共12页
The purpose of this research was to investigate the relationship between soil biota such as microbial activity,soil fauna(e.g.,earthworms and enchytraeids),and soil physical and chemical properties.The study area was ... The purpose of this research was to investigate the relationship between soil biota such as microbial activity,soil fauna(e.g.,earthworms and enchytraeids),and soil physical and chemical properties.The study area was located in Pieniny National Park(PNP)in the Carpathian Mountains in southern Poland.Soil samples were collected from six forest monitoring areas of PNP from two soil layers(at 0–15 cm and 15–30 cm down,respectively).The investigated soils were classified to eutric cambisols and had silt or silt loam soil texture.Upon analysis,soil aggregate stability index was connected with other physical,chemical,and biological soil properties.It was noted that the stability index of 3 mm to 5 mm soil aggregates influenced pH and dissolved organic carbon.The stability index of 2 mm to 3 mm soil aggregates was positively correlated with dissolved organic carbon,soil moisture,microbial biomass carbon,total organic carbon,total nitrogen,and enchytraeid density,and negatively correlated with bulk density,particle density,porosity,and permanent wilting point.The stability index of 1 mm to 2 mm soil aggregates was positively correlated with total nitrogen,enchytraeid and earthworm density and negatively correlated with particle density,porosity,and permanent wilting point.The study has shown what factors create a stable soil structure in the forest soils of PNP. 展开更多
关键词 AGGREGATE stability FOREST SOILS MICROORGANISMS Earthworms ENCHYTRAEIDS Physical PROPERTIES Chemical PROPERTIES
A physical channel-potential and drain-current model for asymmetric dual-gate a-IGZO TFTs
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作者 Minxi CAI Ruohe YAO 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第6期180-182,共3页
Dear editor,A dual-gate (DG) structure demonstrably has improved the device performance and stability of amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs), making circuits faster, less powerconsuming, and more s... Dear editor,A dual-gate (DG) structure demonstrably has improved the device performance and stability of amorphous InGaZnO (a-IGZO) thin-film transistors (TFTs), making circuits faster, less powerconsuming, and more stable (1–3)Physical device modeling has thus generated much interest in circuit design. Ref. 展开更多
关键词 A physical channel-potential and drain-current model for ASYMMETRIC DUAL-GATE a-IGZO TFTS
A case report of pseudo–pseudo Meigs’ syndrome
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作者 Ting Li Qi-Bing Xie 《中华医学杂志:英文版》 SCIE CAS CSCD 2019年第12期1497-1498,共2页
A 24-year-old female patient was admitted to our department with complaints of fatigue and pedal edema. She was diagnosed with systemic lupus erythematosus (SLE) 4 years ago and thus the diagnostic criteria could not ... A 24-year-old female patient was admitted to our department with complaints of fatigue and pedal edema. She was diagnosed with systemic lupus erythematosus (SLE) 4 years ago and thus the diagnostic criteria could not be traced. She had been treated with prednisolone, hydroxychloroquine, and cyclophosphamide for 2 years, and her disease was controlled in stable condition. Occasionally, pain on her lower extremity was her only complaint, which could be relieved by prednisolone. Eight months before admission to our hospital, she got progressive abdominal distension and edema of lower extremities. Abdominal ultrasonography at the local hospital showed ascites;so the patient was treated with diuretic, which made her feel much better. But the patient presented herself with shortness of breath to the local hospital 5 months later. Computed tomography (CT) scan of the thorax showed bilateral pleural effusion. Again, she took diuretic but no significant relief was achieved. In March 2017, the patient was admitted to our department. On physical examination, she had a normal temperature and blood pressure. She was identified with diminished breath sounds, ascites, and edema of the two legs. Her ankles were swollen and tender. Laboratory findings were as follows: white blood cell (WBC) was 1340/mm3, but there was no anemia or thrombocytopenia. C-reactive protein was 14 mg/dL. The antinuclear antibody titer was 1:320 (granular type), whereas anti-double-stranded DNA antibody, anti-Sm antibody, anticardiolipin antibodies, and lupus anticoagulant were negative. Complement C3 was 45.1 mg/dL (normal range 78.5–152.0 mg/dL) and C4 was 4.84 mg/dL (normal range 14.5–36 mg/dL). Coombs test was positive. Proteinuria was quantified at 0.36 g/24 h and kidney function was normal. Albumin was 3.35 g/dL and ferritin was 42.49 ng/mL. CA125 was 949 IU/mL (normal range 0–35 IU/mL), whereas other tumor markers including alpha fetoprotein (AFP), carcino-embryonic antigen (CEA), and CA199 were normal. CT scan of the thorax showed pleuroper 展开更多
关键词 ULTRASONOGRAPHY ERYTHEMATOSUS case protein PHYSICAL was SCAN CA125
Analysis on nasal airway by using scale-adaptive simulation combined with standard κ-ω model and 3D printing modeling physical experiment 预览
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作者 Jiemin Zhan Yangyang Xi +2 位作者 Kay Lin Weiguang Yu Wenqing Hu 《力学快报:英文版》 CAS CSCD 2019年第4期215-219,I0006共6页
The physiological structure of the upper respiratory tract is complex and varies with each individual,and the circulating air has turbulent performance.In this paper,based on computed tomography(CT)medical images publ... The physiological structure of the upper respiratory tract is complex and varies with each individual,and the circulating air has turbulent performance.In this paper,based on computed tomography(CT)medical images published online and the three-dimensional(3D)printing technology,a 3D model of the human upper respiratory tract was reconstructed and an experimental device of the upper respiratory tract was made.We implemented the respiratory experiment and measured the flow rate,and a scale-adaptive κ-ω model is applied for numerical simulation,the results are in good agreement.The flow field during respiratory was analyzed by coronal velocity cross section,vortex line and particle tracks.We found that the relatively strong shear effect happens at the areas of nasal valve and nasopharynx.In the middle and upper nasal tract,vortex line separation occurs and there is significant passage effect.The results indicate that SAS method is effective in studying upper respiratory airflow. 展开更多
关键词 3D PRINTER Scale-adaptive SIMULATION Upper RESPIRATORY TRACT Physical experiment
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A new physical simulation tool to predict the interface of dissimilar aluminum to steel welds performed by friction melt bonding
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作者 T.Sapanathan N. Jimenez-Mena +5 位作者 I. Sabirov M.A. Monclus J.M. Molina-Aldaregui P. Xia L. Zhao A. Simar 《材料科学技术学报:英文版》 SCIE EI CAS CSCD 2019年第9期2048-2057,共10页
Optimization of the intermetallic layer thickness and the suppression of interfacial defects are key elements to improve the load bearing capacity of dissimilar joints. However, till date we do not have a systematic t... Optimization of the intermetallic layer thickness and the suppression of interfacial defects are key elements to improve the load bearing capacity of dissimilar joints. However, till date we do not have a systematic tool to investigate the dissimilar joints and the intermetallic properties produced by a welding condition. Friction Melt Bonding (FMB) is a recently developed technique for joining dissimilar metals that also does not exempt to these challenges. The FMB of DP980 and A16061-T6 was investigated using a new physical simulation tool, based on Gleeble thermo-mechanical simulator, to understand the effect of individual parameter on the intermetallic formation. The proposed method demonstrates its capability in reproducing the intermetallic characteristics, including the thickness of intermetallic bonding layer, the morphology and texture of its constituents (Fe2AU and Fe4Ali3), as well as their nanohardness and reduced modulus. The advantages of physical simulation tool can enable novel developing routes for the development of dissimilar metal joining processes and facilitate to reach the requiring load bearing capacity of the joints. 展开更多
关键词 PHYSICAL simulation INTERFACE INTERMETALLICS NANOINDENTATION Joining
Tribological Properties of Lubricating Oils with Triethanolamine Borate under Electromagnetic Field 预览
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作者 Wang Xin Fang Jianhua +2 位作者 Jiang Zeqi Gu Kecheng Liu Ping 《中国炼油与石油化工:英文版》 SCIE CAS 2019年第3期112-118,共7页
Tribological properties of 150SN mineral oil and lubricating oils containing triethanolamine borate(TBE)with and without electromagnetic field impact were evaluated on a modified four-ball tribo-tester.The characteris... Tribological properties of 150SN mineral oil and lubricating oils containing triethanolamine borate(TBE)with and without electromagnetic field impact were evaluated on a modified four-ball tribo-tester.The characteristics of the worn surfaces were studied by scanning electronic microscopy(SEM),energy dispersive spectrometry(EDS)and X-ray photoelectron spectroscopy(XPS).Moreover,the tribological mechanisms are discussed from the viewpoint of physical effect and chemical effect.The results indicated that the friction coefficients and wear scar diameters(WSDs)lubricated by 150SN mineral oil under electromagnetic field were higher than those without electromagnetism impact.The WSDs of steel balls lubricated by TBE-doped oils under electromagnetic field were smaller than those obtained from non-electromagnetic field,but the friction coefficients were higher than those under non-electromagnetic field.A protective coating consists of wear particles could be formed on the frictional surface due to the physical effect of electromagnetic field on wear debris.The electromagnetic field could facilitate the interaction of elemental boron and nitrogen in TBE with metal interfaces,and contributes to forming tribo-chemical reaction film to reduce friction and wear. 展开更多
关键词 ELECTROMAGNETIC field TRIETHANOLAMINE BORATE TRIBOLOGICAL properties PHYSICAL EFFECT chemical EFFECT
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The Theory of Dove-like Particles 预览
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作者 SUN Zuodong 《美中医学:英文版》 2019年第2期73-99,共27页
Objective:Alzheimer‘s disease(AD)has been reported for more than 100 years since its first discovery in 1906.There has been no significant progress in the study of its real causes and pathogenesis.The viewpoint of th... Objective:Alzheimer‘s disease(AD)has been reported for more than 100 years since its first discovery in 1906.There has been no significant progress in the study of its real causes and pathogenesis.The viewpoint of this paper is a heuristic viewpoint based on brain cell activation theory under such background.In this paper,the pathogenesis of sporadic AD is discussed at molecular level by applying the principles of cell physics and biology.The purpose of this paper is to harmonize the existing theories of etiology of AD and to solve the source problems that have plagued the research field of neurodegenerative diseases for a long time.Method:(1)Discuss the relationship with the existing hypothesis:the Aβprotein hypothesis,the tau protein hypothesis,the presenilin(PS)hypothesis,the apolipoprotein E(ApoE)hypothesis,the cholinergic hypothesis,the inflammatory hypothesis;(2)Demonstration:biophysical proof,medical pathological proof,biological model proof;(3)Interpretation:ion channel and blood-brain barrier,potassium ion and potassium channel,ion pump and epilepsy and cancer,A beta protein and spots and plaques,related AD solutions.Result:(1)Abeta is not the cause of AD,but the remains of brain cells after abnormal apoptosis;(2)The K^+concentration difference of 0.00001%which causes the great change of membrane potential is the effective concentration,which can not be neglected;(3)Abnormal impairment of potassium channels and early entry of sodium ions to occupy potassium positions are related to epilepsy,cancer and HeLa cells;(4)AD is a physical disease,especially transcranial magnetoelectricity stimulation,should be the first choice for treatment,which can activate abnormal neurons accurately without interfering with normal neurons.Conclusion:(1)Basic contents:excess cations are transferred from extracellular to intracellular.They compete position with potassium ions on the inner surface of cell membranes,thus abatementing the membrane potential,making action potential unable to activate calcium channels normally, 展开更多
关键词 Alzheimer ETIOLOGY CATIONIC PLACEMENT AMYLOID PLAQUE cell REMAINS physical mean.
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Mass transport mechanisms within pervaporation membranes
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作者 Yimeng Song Fusheng Pan +2 位作者 Ying Li Kaidong Quan Zhongyi Jiang 《化学科学与工程前沿:英文版》 EI CAS CSCD 2019年第3期458-474,共17页
Pervaporation is an energy-efficient membrane technology for separating liquid molecules of similar physical properties, which may compete or combine with distillation separation technology in a number of applications... Pervaporation is an energy-efficient membrane technology for separating liquid molecules of similar physical properties, which may compete or combine with distillation separation technology in a number of applications. With the rapid development of new membrane materials, the pervaporation performance was significantly improved. Fundamental understanding of the mass transport mechanisms is crucial for the rational design of membrane materials and efficient intensification of pervaporation process. Based on the interactions between permeate molecules and membranes, this review focuses on two categories of mass transport mechanisms within pervaporation membranes: physical mechanism (solutiondiffusion mechanism, molecular sieving mechanism) and chemical mechanism (facilitated transport mechanism). Furthermore, the optimal integration and evolution of different mass transport mechanisms are briefly introduced. Material selection and relevant applications are highlighted under the guidance of mass transport mechanisms. Finally, the current challenges and future perspectives are tentatively identified. 展开更多
关键词 PERVAPORATION MEMBRANE mass transport MECHANISMS PHYSICAL MECHANISM chemical MECHANISM
Mechanical Relaxation of a Ti36.2Zr30.3Cu8.3Fe4Be21.2 Bulk Metallic Glass:Experiments and Theoretical Analysis
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作者 J.C.Qiao Y.H.Chen +3 位作者 G.J.Lyu K.K.Song J.M.Pelletier Y.Yao 《金属学报:英文版》 SCIE EI CAS CSCD 2019年第6期726-732,共7页
The dynamic mechanical relaxation behavior of Ti36.2Zr30.3Cu8.3Fe4Be21.2 bulk metallic glass with good glass-forming ability was investigated by mechanical spectroscopy.The mechanical relaxation behavior was analyzed ... The dynamic mechanical relaxation behavior of Ti36.2Zr30.3Cu8.3Fe4Be21.2 bulk metallic glass with good glass-forming ability was investigated by mechanical spectroscopy.The mechanical relaxation behavior was analyzed in the framework of quasi-point defects model.The experimental results demonstrate that the atomic mobility of the metallic glass is closely associated with the correlation factorχ.The physical aging below the glass transition temperature T g shows a non-Debye relaxation behavior,which could be well described by stretched Kohlrausch exponential equation.The Kohlrausch exponentβaging reflects the dynamic heterogeneities of the metallic glass.Both concentration of"defects"and atomic mobility decrease caused by the in situ successive heating during the mechanical spectroscopy experiments. 展开更多
关键词 Metallic GLASSES Mechanical RELAXATION Physical AGING Quasi-point defects
A Summary of Methods for Measuring Physical Activity in Urban Planning Research 预览
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作者 XU Ke 《景观研究:英文版》 2019年第4期51-57,共7页
Research on the built environment and physical activity has become a hot topic in the field of urban planning. When discussing the relationship between the built environment and physical activity, how to measure physi... Research on the built environment and physical activity has become a hot topic in the field of urban planning. When discussing the relationship between the built environment and physical activity, how to measure physical activity reasonably and effectively is an important technical link that determines whether the research is accurate and reliable. At present, the measurement methods of physical activity in domestic and foreign research lack a systematic analysis. Based on the analysis of 27 empirical studies on the relationship between the built environment and physical activity, this paper explores the scope of application of different measurement methods of physical activity from the perspectives of economic cost, observation unit, and information collection. The research shows that:① Self-report questionnaires can provide information of built environment, but may overestimate the intensity of physical activity;② a single motion sensor can record the duration, intensity and frequency of physical activity objectively and precisely, but cannot reflect the environment information and the types of physical activity;③ the combination of two methods provide more possibilities for measuring physical activity. Currently, the relationship between the built environment and physical activity in urban China has not yet been clarified. In the future research of healthy cities, it is recommended to consider the status quo of China’s high-density urban built environment, select appropriate measurement methods and recording tools, and comprehensively record the physical activity characteristics of urban residents, so as to better reveal the influence mechanism of the built environment on physical activity. 展开更多
关键词 PHYSICAL activity Built environment HEALTHY CITY
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Superimposed characteristics and genetic mechanism of strike-slip faults in the Bohai Sea, China 预览
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作者 HU Zhiwei XU Changgui +4 位作者 WANG Deying REN Jian LIU Yubo XIAO Shuguang ZHOU Xin 《石油勘探与开发:英文版》 2019年第2期265-279,共15页
Based on the 3 D seismic structure interpretation of Bohai Sea, combined with physical modeling of structure, structural style analysis and apatite fission track simulation, the structural characteristics and genetic ... Based on the 3 D seismic structure interpretation of Bohai Sea, combined with physical modeling of structure, structural style analysis and apatite fission track simulation, the structural characteristics and genetic mechanism of the Cenozoic strike-slip faults in Bohai Sea were investigated. The results show that Tanlu strike-slip fault experienced three stages of strike-slip activities in the Cenozoic,and the transition from left-lateral strike to right-lateral strike-slip was completed at the end of the fourth member of the Shahejie Formation. The strike-slip faults in the Bohai Sea have the characteristics of multi-stage and multi-strength stress superposition. According to the superimposed forms of different strengths, different properties and different ratios, they can be divided into three major genetic types,extension and strike-slip superimposition, extension and extrusion superimposition, extrusion and strike-slip superimposition, and fifteen typical structure patterns. Affected by multiple changes in the direction and rate of subduction of the Cenozoic Pacific plate, the difference between the Cenozoic extension and the strike-slip in the Bohai Sea area leads to the diversity of the fault system and the zoning of the depression structure. According to superimposition features of faults, the Bohai Sea area can be divided into the Liaoxi S-type weak strike-slip zone, Liaodong braided strong strike-slip zone, Boxi conjugated medium strike-slip zone, Bodong brush structure medium strike-slip zone and Bonan parallel strong strike-slip zone. These zones differ in oil and gas accumulation features. 展开更多
关键词 STRIKE-SLIP FAULT SUPERIMPOSITION characteristic genetic mechanism Tanlu FAULT Bohai BAY BASIN Bohai Sea physical modeling of structure
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