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Association of daily sitting time and leisure-time physical activity with body fat among U.S.adults 被引量:1
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作者 Jingwen Liao Min Hu +4 位作者 Kellie Imm Clifton J.Holmes Jie Zhu Chao Cao Lin Yang 《Journal of Sport and Health Science》 SCIE CAS CSCD 2024年第2期195-203,共9页
Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investi... Background:Prolonged sitting and reduced physical activity lead to low energy expenditures.However,little is known about the joint impact of daily sitting time and physical activity on body fat distribution.We investigated the independent and joint associations of daily sitting time and physical activity with body fat among adults.Methods:This was a cross-sectional analysis of U.S.nationally representative data from the National Health and Nutrition Examination Survey2011-2018 among adults aged 20 years or older.Daily sitting time and leisure-time physical activity(LTPA)were self-reported using the Global Physical Activity Questionnaire.Body fat(total and trunk fat percentage)was determined via dual X-ray absorptiometry.Results:Among 10,808 adults,about 54.6%spent 6 h/day or more sitting;more than one-half reported no LTPA(inactive)or less than 150 min/week LTPA(insufficiently active)with only 43.3%reported 150 min/week or more LTPA(active)in the past week.After fully adjusting for sociodemographic data,lifestyle behaviors,and chronic conditions,prolonged sitting time and low levels of LTPA were associated with higher total and trunk fat percentages in both sexes.When stratifying by LTPA,the association between daily sitting time and body fat appeared to be stronger in those who were inactive/insuufficiently active.In the joint analyses,inactive/insuufficiently active adults who reported sitting more than 8 h/day had the highest total(female:3.99%(95%confidence interval(95%CI):3.09%-4.88%);male:3.79%(95%CI:2.75%-4.82%))and trunk body fat percentages(female:4.21%(95%CI:3.09%-5.32%);male:4.07%(95%CI:2.95%-5.19%))when compared with those who were active and sitting less than 4 h/day.Conclusion:Prolonged daily sitting time was associated with increased body fat among U.S.adults.The higher body fat associated with 6 h/day sitting may not be offset by achieving recommended levels of physical activity. 展开更多
关键词 ADULTS Body fat distribution Physical activity sitting time
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Effect of PKD1L1 Mutation on its Interaction with PKD2 to Cause Situs Inversus Totalis
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作者 Fatima Haroon Salma Saeed Khan Assad Ullah 《Journal of Clinical and Nursing Research》 2024年第8期183-206,共24页
Situs inversus totalis(SIT)is a rare homozygous recessive disease caused by the mutation in PKD1L1,which is required for normal interaction with PKD2 and leads to different complications such as respiratory disorders,... Situs inversus totalis(SIT)is a rare homozygous recessive disease caused by the mutation in PKD1L1,which is required for normal interaction with PKD2 and leads to different complications such as respiratory disorders,brain disorders and even obesity.The present study was designed to find out the mutational effect on the binding of PKD2 with mutated PKD1L1,which leads to SIT.The three-dimensional(3D)structure of wild type and mutated PKD1L1 was predicted with>90%confidence using different online tools.The different online tools that were employed were SWISS-MODEL,Phyre2(normal&intensive)and i-TASSER.To compute the physiochemical properties of PKD1L1(wild&mutated)and PKD2 in silico approaches were employed using the ExPASy ProtParam tool.Physicochemical properties such as molecular weight,isoelectric point,the total number of negatively and positively charged residues,extinction coefficient,half-life,instability and aliphatic index,grand average of hydropathicity,and amino acid percentage were calculated.A lot of variability was observed in these parameters among PKD1L1 and PKD2,which accounted for diversification in their functional properties.The theoretical pI points showed that PKD1L1(whole)is more basic with 6.64 pI compared to its first chain TOPO_DOM(amino acids from 1–1748)has a pI of 5.62 which means it is basic while PKD2 have the lowest pI point of 5.34.Docking was performed using the PatchDock and ClusPro online tools. 展开更多
关键词 sit PKD1L1 PKD2 SWISS-MODEL ClusPro
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Too Much Sitting
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《空中英语教室(初级版.大家说英语)》 2024年第9期1-1,共1页
Do you spend many hours of the day siting?When you sit,you use less energy than you do when you are active.Siting toomuch hurts yourback,and it's bad for your heart it causes you to gain weight and may even increa... Do you spend many hours of the day siting?When you sit,you use less energy than you do when you are active.Siting toomuch hurts yourback,and it's bad for your heart it causes you to gain weight and may even increase your risk of cancer.How can you avoid siting too much?Every 30minutes,move and stretch.Better on thephone orwatch TV. 展开更多
关键词 cancer. SPEND sit
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基于SIT理论的高校体育课程思政教学互动策略探究 被引量:5
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作者 王爱萍 祝安凤 《广州体育学院学报》 北大核心 2023年第6期44-51,共8页
以社会学符号互动理论(SIT)为基础,围绕体育课程思政这一时代命题,运用文献资料法、观察法等研究方法,探讨高校体育课程思政教学互动问题与策略。研究认为,当前我国高校体育课程思政教学存在互动主体分散、互动模式单一、互动内容分化... 以社会学符号互动理论(SIT)为基础,围绕体育课程思政这一时代命题,运用文献资料法、观察法等研究方法,探讨高校体育课程思政教学互动问题与策略。研究认为,当前我国高校体育课程思政教学存在互动主体分散、互动模式单一、互动内容分化等不足,认为应引导教师采取主体协同、符号融合、多维表达等策略,灵活运用相关符号,实现良好的教学互动。 展开更多
关键词 体育课程思政 符号互动理论(sit) 体育教学 教学互动
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The impact of height-adjustable desks and classroom prompts on classroom sitting time,social,and motivational factors among adolescents
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作者 Bronwyn Sudholz Ana Marıa Contardo Ayala +6 位作者 Anna Timperio David W.Dunstan David E.Conroy Gavin Abbott Bernie Holland Lauren Arundell Jo Salmon 《Journal of Sport and Health Science》 SCIE CSCD 2023年第1期97-105,共9页
Purpose:This quasi-experimental study examined the impact of height-adjustable desks in combination with prompts to break up prolonged sitting time during class time and identified social and motivational factors asso... Purpose:This quasi-experimental study examined the impact of height-adjustable desks in combination with prompts to break up prolonged sitting time during class time and identified social and motivational factors associated with breaking up sitting time among adolescents.Teachers’perceptions of strategies were also examined.Methods:Over 17 weeks,1 classroom in a government secondary school in Melbourne,Australia,was equipped with 27 height-adjustable desks and prompts(posters and desk stickers)to break up classroom sitting time.Teachers received professional development in the use of the desks and prompts.One group of adolescents(n=55)had 2-5 lessons/week using the height-adjustable desks in an intervention classroom,and a comparison group matched by year level and subject(n=50)was taught in traditional“seated”classrooms.Adolescents wore an activPAL monitor at baseline(T0),4 weeks(T1),and 17 weeks(T2)and completed a survey at T0 and T2.Six teachers participated in interviews at T2.Effect sizes were calculated(d).Results:Linear mixed models found that,compared to the traditional“seated”classrooms,the adolescents in the intervention classroom had significantly lower sitting time(T1:-9.7 min/lesson,d=-0.96;T2:-6.7 min/lesson,d=-0.70)and time spent in sitting bouts>15 min(T2:-11.2 min/lesson,d=-0.62),and had significantly higher standing time(T1:7.3 min/lesson,d=0.84;T2:5.8 min/lesson,d=0.91),number of breaks from sitting(T1:1.3 breaks/lesson,d=0.49;T2:1.8 breaks/lesson,d=0.67),and stepping time(T1:2.5 min/lesson,d=0.66).Intervention classroom adolescents reported greater habit strength(d=0.58),self-efficacy for breaking up sitting time(d=0.75),and indicated that having a teacher/classmate remind them to stand as helpful(d=0.50).Conclusion:This intervention shows promise for targeting sitting behaviors in the classroom and indicates that incorporating social and motivational strategies may further enhance outcomes. 展开更多
关键词 ADOLESCENT School Sedentary behavior sitTING STANDING
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基于ULCIZ和SIT的罗非鱼耐寒性能测定模型 被引量:2
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作者 杜雪松 宾石玉 +5 位作者 林勇 唐章生 张永德 曾兰 杨慧赞 陈忠 《广西师范大学学报(自然科学版)》 CAS 北大核心 2013年第4期134-139,共6页
本文针对单一Logistic模型的不足之处,分析冷伤害上限温度(ULCIZ)、伤害低温总和(SIT)和双变量Logistic回归模型在罗非鱼低温耐寒性能研究中应用的可能性和优点,并根据罗非鱼低温胁迫试验的本身特点对其进行了改进。
关键词 冷伤害上限温度(ULCIZ) 伤害低温总和(sit) 双变量Logistic回归 罗非鱼 耐寒性能 UPPER limit of CHILL injuryzone (ULCIZ) SUM of injurious temperature (sit)
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Effect of Lumbar Spinal Point Injection on Sitting Function in Children with Cerebral Palsy
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作者 Tian Ma Ceng Li Yabo Liu 《Yangtze Medicine》 2023年第3期171-176,共6页
Objective: To observe the effect of lumbar spinal point injection on sitting function in children with cerebral palsy. Method: Sixty-two children with post-confirmed cerebral palsy were randomly divided into control g... Objective: To observe the effect of lumbar spinal point injection on sitting function in children with cerebral palsy. Method: Sixty-two children with post-confirmed cerebral palsy were randomly divided into control group and treatment group, 31 each. The control group was given conventional rehabilitation treatment, and the treatment group was given lumbar chiropspinal acupoint injection on the basis of the treatment method of the control group. After 3 consecutive courses of treatment, the sitting score of the two groups before and after treatment (GMFM88) was used to evaluate the sitting score before and after treatment. Outcome: Before treatment, the two groups were evaluated and the differences were not statistically significant (p > 0.05), which was comparable. The two groups (GMFM88) after treatment had significantly increased the differential values, and the difference was statistically significant compared with the same group before treatment (p Conclusion: Conventional rehabilitation combined with lumbar spinal point injection can effectively improve the sitting motor function of children with cerebral palsy. 展开更多
关键词 Children with Cerebral Palsy Lumbar Segmentation of Spinal Points Acupuncture Point Injection Gross Motor Function (sitting Area)
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基于LabVIEWSIT的过程控制系统仿真 被引量:12
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作者 向学军 刘平 杨盛 《三峡大学学报(自然科学版)》 CAS 2006年第4期328-330,共3页
首先介绍了虚拟仪器软件LabVIEW及simulation interface toolkit(SIT),利用LabVIEW的可视化技术,直观、生动地模拟工业系统的运行状况,可以使仿真具有更好的效果.LabVIEWSIT可以快速地将LabVIEW与Matlab/Simulink结合进行系统的仿真.以... 首先介绍了虚拟仪器软件LabVIEW及simulation interface toolkit(SIT),利用LabVIEW的可视化技术,直观、生动地模拟工业系统的运行状况,可以使仿真具有更好的效果.LabVIEWSIT可以快速地将LabVIEW与Matlab/Simulink结合进行系统的仿真.以一个二阶液位过程控制系统为例介绍了基于LabVIEW SIT的过程控制系统仿真的设计. 展开更多
关键词 LABVIEW simulation INTERFACE toolkit(sit) 过程控制
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SIT耐压容量的控制和工艺调节 被引量:4
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作者 刘瑞喜 李思渊 何山虎 《半导体技术》 CAS CSCD 北大核心 1998年第4期19-22,共4页
对静电感应晶体管(SIT)栅-漏、栅-源击穿电压的控制和工艺调节方法进行了探讨,对栅-源连通和栅-漏耐压的钳位问题进行了分析。
关键词 sit 耐压 静电感应晶体管 制造工艺
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桔小实蝇及其SIT防治技术应用研究进展 被引量:5
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作者 李姣 肖铁光 周社文 《作物研究》 2007年第2期145-148,共4页
桔小实蝇Bactrocera dorsalis原产于东南亚,是我国重要的检疫性有害生物。综述了桔小实蝇各虫态发育特性及行为偏好特性,并对SIT防治技术的应用进行了概括,为更好地防治桔小实蝇和应用SIT防治技术提供参考。
关键词 桔小实蝇 发育特性 sit 防治
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特异性免疫疗法(SIT)与卡介苗多糖核酸联合治疗花粉症的临床研究 被引量:3
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作者 魏庆宇 朱晓明 +1 位作者 叶晶 谭雯 《辽宁医学杂志》 2005年第6期293-295,共3页
目的探讨卡介苗多糖核酸(BCG-PSN)在花粉症特异性免疫治疗中的作用。方法对比卡介苗多糖核酸与SIT联合治疗花粉症和单用SIT治疗花粉症的临床疗效,并比较治疗前后血清中IFN-γ、IL-4和ICAM-1含量的变化。结果联合治疗组总有效率为89.1%。... 目的探讨卡介苗多糖核酸(BCG-PSN)在花粉症特异性免疫治疗中的作用。方法对比卡介苗多糖核酸与SIT联合治疗花粉症和单用SIT治疗花粉症的临床疗效,并比较治疗前后血清中IFN-γ、IL-4和ICAM-1含量的变化。结果联合治疗组总有效率为89.1%。SIT组总有效率为76.4%,联合治疗组血清中三种细胞因子水平的变化更明显。结论联合治疗组的有效率明显优于SIT组,卡介苗多糖核酸与SIT合用能够明显提高花粉症SIT疗效。 展开更多
关键词 花粉症 特异性免疫治疗(sit) 卡介苗多糖核酸(BCG-PSN) 细胞因子
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桉树焦枯病菌SIT转运蛋白的鉴定与表达
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作者 刘宏毅 陈慧洁 +3 位作者 李慧敏 叶小真 冯丽贞 郭朦朦 《西北农林科技大学学报(自然科学版)》 CSCD 北大核心 2018年第11期18-24,共7页
【目的】揭示SIT转运蛋白家族在焦枯病菌铁元素摄入机制,以及铁载体-铁转运蛋白在焦枯病菌侵染桉树过程中所扮演的角色。【方法】采用HMMER软件对焦枯病菌SIT转运蛋白进行鉴定,并用InterPro、TMHMM、TCDB数据库等的在线服务对焦枯病菌SI... 【目的】揭示SIT转运蛋白家族在焦枯病菌铁元素摄入机制,以及铁载体-铁转运蛋白在焦枯病菌侵染桉树过程中所扮演的角色。【方法】采用HMMER软件对焦枯病菌SIT转运蛋白进行鉴定,并用InterPro、TMHMM、TCDB数据库等的在线服务对焦枯病菌SIT转运蛋白的结构域、跨膜螺旋和功能进行预测,用MEGA7.0软件进行多菌种比较分析,最后采用qPCR对焦枯病菌侵染桉树48h时SIT基因的转录表达情况进行验证。【结果】桉树焦枯病菌共含有16个SIT转运蛋白,约占总编码蛋白的0.11%,主要分为铁-铁载体转运蛋白、铁载体-铁:H+同向转运蛋白和铁载体-铁转运蛋白;亚细胞定位预测结果显示,除预测CpSit13转运蛋白位于内质网上外,其余均在细胞膜上。桉树焦枯病菌SIT转运蛋白的序列长度为400~603aa,其结构域均为MFS结构域,跨膜螺旋为10~14个。基因表达谱分析显示,有10个SIT基因上调表达,有2个下调表达,有4个表达不显著。其中CpSit1、CpSit5、CpSit8、CpSit14和CpSit16相对分支中其他基因具有较高的转录量。qPCR验证结果与基因表达谱具有较高的一致性。【结论】CpSit1、CpSit5、CpSit8、CpSit14和CpSit16基因在焦枯病菌侵染桉树过程中具有较为重要的作用。 展开更多
关键词 桉树 焦枯病菌 sit蛋白 生物信息学 转录表达
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高增益硅超高频功率SIT 被引量:1
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作者 梁法国 夏曼 刘红兵 《半导体情报》 1996年第4期24-27,共4页
采用全自对准介质盖栅工艺,通过合理设计,研制成功一种高增益硅超高频功率SIT。在400MHz工作频率、50V工作电压下,其输出功率Po为40W,漏极效率η_D接近60%,功率增益Gp高达16dB。Po=25W时,三阶... 采用全自对准介质盖栅工艺,通过合理设计,研制成功一种高增益硅超高频功率SIT。在400MHz工作频率、50V工作电压下,其输出功率Po为40W,漏极效率η_D接近60%,功率增益Gp高达16dB。Po=25W时,三阶交调3IM为-16dB;Po=2.5W时,3IM为-50dB。 展开更多
关键词 高增益 sit 半导体器件 制造工艺
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Does light-intensity physical activity moderate the relationship between sitting time and adiposity markers in adolescents? 被引量:1
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作者 Ana María Contardo Ayala Jo Salmon +2 位作者 David W.Dunstan Lauren Arundell Anna Timperio 《Journal of Sport and Health Science》 SCIE 2022年第5期613-619,共7页
Background:While the relationship between sedentary time and adiposity markers may be independent of moderate-to-vigorous intensity physical activity(MVPA) among adolescents,little is known about the role of light-int... Background:While the relationship between sedentary time and adiposity markers may be independent of moderate-to-vigorous intensity physical activity(MVPA) among adolescents,little is known about the role of light-intensity physical activity(LIPA) in this relationship.The aim of this cross-sectional study was to examine whether device-measured LIPA and MVPA moderate the associations between objectively measured sitting time and adiposity markers(body mass index(BMI)) and waist circumference(WC)) among adolescents.Methods:This study included accelerometer and inclinometer data obtained from 219 adolescents(age=14.9±1.6 years,mean± SD),collected during 2014 and 2015 in Melbourne,Australia.ActiGraph GT3 X accelerometers were used to determine time spent in total-LIPA(101 counts/min to 3.99 metabolic equivalents(METs)) was dichotomized into low-LIPA(101-799 counts/min) and high LIPA(800 counts/min to 3.99 METs),and MVPA(> 4 METs).The average time spent sitting was obtained from activPAL inclinometers.Anthropometric measures were assessed by trained staff.Interactions between sitting and total-LIPA,low-LIPA,high-LIPA,and MVPA on BMI z-score(zBMI) and WC z-score(zWC),respectively,were examined using linear regression,adjusting for age and sex;and moderation by total-LIPA,low-LIPA,high-LIPA,and MVPA were examined by adding interaction terms.Significant interaction effects were probed by comparing associations at the mean and at 1 SD below and above the mean.Results:Total-LIPA significantly moderated the association between sitting time and zBMI,and low-LIPA significantly moderated the association between sitting time and zBMI and zWC.No other associations were found for total-LIPA,high-LIPA,or MVPA.Specifically,at high levels of total-LIPA(+1 SD),there is a negative association between sitting time and zBMI.In addition,at high levels of low-LIPA(+1 SD),there is a negative association between sitting time and zBMI and zWC.Conclusion:Associations between sitting and adiposity depended on time spent in total-LIPA and low-LIPA,but not high-LIPA or MVPA.Results suggest that increasing time spent in LIP A may provide protection from the deleterious effects of sitting on adiposity markers among adolescents.Experimental evidence is needed to support these conclusions. 展开更多
关键词 Adolescents Anthropometric measures OBEsitY Physical activity Sedentary behavior sitting time
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静电感应晶体管(SIT)电性能的控制 被引量:1
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作者 李思渊 刘瑞喜 李海蓉 《甘肃教育学院学报(自然科学版)》 1998年第1期32-39,共8页
静电感应晶体管(SIT)的I-V特性(包括类三极管、类五极管以及三一五极管的混合特性)与器件的结构密切相关.沟道长度lc、沟道宽度dc、比值lc/dc以及沟道掺杂浓度ND等均为确定SIT运用方式的重要参数.如何控制这些参数并达到最佳匹... 静电感应晶体管(SIT)的I-V特性(包括类三极管、类五极管以及三一五极管的混合特性)与器件的结构密切相关.沟道长度lc、沟道宽度dc、比值lc/dc以及沟道掺杂浓度ND等均为确定SIT运用方式的重要参数.如何控制这些参数并达到最佳匹配进而实现优良的I-V特性,是个关键而且困难的问题.本文给出了上述参数控制的一般原则、方法,还给出了控制的判据,引人了一个控制因子β,特别是对混合特性的控制问题进行了详细的讨论.由于混合特性低的通态电阻和高的AC功率效率,它更为适于低阻负载直接驱动电路. 展开更多
关键词 静电感应晶体管 电性能 sit 沟道长度 沟道宽度
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从SIT学习项目看对外汉语教学速成教材的编写 被引量:1
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作者 杨丽姣 《云南师范大学学报(教育科学版)》 2001年第1期38-41,共4页
本文从最近十年间出版的对外汉语教学速成教材中选取了六本较有代表性的教材,根据六本教材的课文数、词汇量、语音、语法点、功能项目、汉字词汇知识点、练习种类七个方面在SIT学习项目中的适应情况作出分析与比较。以期对新的对外汉语... 本文从最近十年间出版的对外汉语教学速成教材中选取了六本较有代表性的教材,根据六本教材的课文数、词汇量、语音、语法点、功能项目、汉字词汇知识点、练习种类七个方面在SIT学习项目中的适应情况作出分析与比较。以期对新的对外汉语教学速成教材的编写提供借鉴。 展开更多
关键词 sit学习项目 对外汉语教学 速成教材 词汇 语法 语音
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基于SIT引力评价的多核中心区半极化结构研究
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作者 史北祥 杨俊宴 谈力 《现代城市研究》 北大核心 2021年第1期66-71,共6页
随着城市中心区规模尺度的不断扩展,在公共服务设施持续集聚及空间不平衡机制作用下,中心区内部会形成多个不同规模、功能及区位特征的硬核,而多硬核的格局一旦形成,便会存在相互间的作用力与竞争关系。这一作用力受空间、业态及交通条... 随着城市中心区规模尺度的不断扩展,在公共服务设施持续集聚及空间不平衡机制作用下,中心区内部会形成多个不同规模、功能及区位特征的硬核,而多硬核的格局一旦形成,便会存在相互间的作用力与竞争关系。这一作用力受空间、业态及交通条件的影响与制约,并具有动态性的特征,使得中心区始终处于整体上极化集聚,而内部结构不断变化的半极化结构状态。文章在深入剖析空间、业态及交通3个因素作用机制的基础上,构建了SIT引力评价模型,对中心区硬核间的结构关系进行评价。评价结果可以直接反映出中心区硬核间的功能结构关系,并对硬核未来的功能结构演替进行预测在此基础上,以南京市新街口中心区为例进行了研究,应用SIT引力评价模型对其功能结构现状及发展进行了评判。 展开更多
关键词 中心区 半极化结构 sit 引力评价 多核
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基于SIT与Duffing振子的微弱信号混沌检测
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作者 谢永兴 林涛 +1 位作者 胡云安 秦亮 《计算机与数字工程》 2014年第10期1875-1878,共4页
利用Duffing振子对特定微弱正弦信号极其敏感以及对噪声免疫的特性,可以将微弱正弦信号引入系统中,根据混沌系统相轨迹的变化将噪声覆盖的微弱正弦信号检测出来。而通过LabVIEW与Matlab/Simulink混合编程,则能实现两者相互通讯、优势互... 利用Duffing振子对特定微弱正弦信号极其敏感以及对噪声免疫的特性,可以将微弱正弦信号引入系统中,根据混沌系统相轨迹的变化将噪声覆盖的微弱正弦信号检测出来。而通过LabVIEW与Matlab/Simulink混合编程,则能实现两者相互通讯、优势互补。利用LabVIEW仿真接口工具包SIT实现混沌微弱信号的检测,检测精度高达-143dB,交互界面更加友好,操作简单易行。 展开更多
关键词 LABVIEW sit DUFFING振子 混合编程 微弱信号检测
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SITS在实验性心肌细胞缺氧/复氧损伤中的作用
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作者 彭少君 晏渠如 《时珍国医国药》 CAS CSCD 北大核心 2008年第8期1984-1985,共2页
目的阐明SITS所产生的心肌保护作用。方法建立缺氧/复氧损伤(A/R)模型及SITS预适应模型,测定心肌细胞的搏动频率、细胞存活率以及细胞培养液中LDH的变化。结果SITS预处理能明显提高A/R损伤后细胞存活率,减少LDH的漏出,与A/R组相比均有... 目的阐明SITS所产生的心肌保护作用。方法建立缺氧/复氧损伤(A/R)模型及SITS预适应模型,测定心肌细胞的搏动频率、细胞存活率以及细胞培养液中LDH的变化。结果SITS预处理能明显提高A/R损伤后细胞存活率,减少LDH的漏出,与A/R组相比均有显著性差异(P<0.01)。结论SITS预处理对心肌细胞A/R具有保护作用。此研究为寻找特异性阻断剂,探讨心肌保护药物的新靶点提供理论与实验依据。 展开更多
关键词 sitS 缺氧/复氧损伤 预处理 心肌细胞
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Temporal Optimality of a Via-Posture on Trajectory during Sit-to-Stand and Back-to-Sit Movements 被引量:1
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作者 Hiroshi R. Yamasaki Urara Nakamura Hiroshi Nagasaki 《Journal of Biomedical Science and Engineering》 2014年第7期387-396,共10页
The purpose of this study was to examine the hypothesis that the minimum angle-jerk with via-point model could account for the temporal consistency of kinematics in sit-to-stand (STS) and back-to-sit (BTS) movements. ... The purpose of this study was to examine the hypothesis that the minimum angle-jerk with via-point model could account for the temporal consistency of kinematics in sit-to-stand (STS) and back-to-sit (BTS) movements. The positions of bony landmarks on the subjects during the tasks were recorded using a Vicon motion analysis system to yield the angular displacement and position of the center of mass (COM) of a three-link rigid body model in the sagittal plane. Minimum angle-jerk and minimum jerk trajectories with a via-point were computed for joint angle and COM, respectively. Five to six candidate points were selected as the via-point from the measured trajectory based on the separate kinematic events. The results show the optimal angular trajectories using the via-points (via-angles) before the seat-off for STS, and at around the seat-contact for BTS resembles the measured angular trajectories well, indicating that the posture at the via-point was temporally optimal to produce the minimum angle-jerk trajectory for both movements. It is hypothesized that the multi-joint angular patterns during STS and BTS movements were organized to pass through the via-point, namely the via-posture along the minimum angle-jerk trajectory. 展开更多
关键词 Temporal OPTIMALITY Via-Posture TRAJECTORY sit-TO-STAND Back-to-sit
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