Accelerometer data requirements for reliable estimation of habitual physical activity and sedentary time of children during the early years - a worked example following a stepped approach

This study presents a worked example of a stepped process to reliably estimate the habitual physical activity and sedentary time of a sample of young children. A total of 299 children (2.9 ± 0.6 years) were recruited. Outcome variables were daily minutes of total physical activity, sedentary time, moderate to vigorous physical activity and proportional values of each variable. In total, 282 (94%) provided 3 h of accelerometer data on ≥1 day and were included in a 6-step process: Step-1: determine minimum wear-time; Step-2: process 7-day-data; Step-3: determine the inclusion of a weekend day; Step-4: examine day-to-day variability; Step-5: calculate single day intraclass correlation (ICC) (2,1); Step-6: calculate number of days required to reach reliability. Following the process the results were, Step-1: 6 h was estimated as minimum wear-time of a standard day. Step-2: 98 (32%) children had ≥6 h wear on 7 days. Step-3: no differences were found between weekdays and weekend days (P ≥ 0.05). Step-4: no differences were found between day-to-day variability (P ≥ 0.05). Step-5: single day ICC’s (2,1) ranged from 0.48 (total physical activity and sedentary time) to 0.53 (proportion of moderate to vigorous physical activity). Step-6: to reach reliability (ICC = 0.7), 3 days were required for all outcomes. In conclusion following a 7 day wear protocol, ≥6 h on any 3 days was found to have acceptable reliability. The stepped-process offers researchers a method to derive sample-specific wear-time criterion.     

单片机延时方法的分析及应用

单片机开发应用中经常用到延时控制，延时控制的基本方法有纯软件、纯硬件及软硬件结合方法，它们都有各自的特点及应用范围，以1秒延时为例给出用三种方法实现的过程，并介绍了软硬件结合延时的应用实例。     

《文馆词林》残篇二考

文章通过对《文馆词林》所存两篇残敕的文本进行分析,并将其与历史资料对照验证,得出此二敕的作者均为唐太宗,此二敕的写作时间分别为贞观二年(528)正月、三月。     

农村小学英语Story time板块教学常见问题及对策

译林版英语教材中的Story time板块是各个单元的核心板块。教师分析了农村小学英语Story time板块教学存在的几个问题,并针对问题提出了解决策略,以期提高英语教学效率。     

论网络时代高校思想政治工作

网络时代,高校师生的学习方式和生活方式发生了深刻变化。互联网在促进教育发展和人才培养的同时,对学生的消极影响不容忽视。要多方面加强思想政治工作,如开辟网上“思想政治教育课堂”、设置“网上德育阵地”、建立信息监控等。     

中国古代职业技术教育之方法

艺徒训练制贯穿中国古代职业教育历史进程，无论是世承制、官工作坊制，还是官工业制、民间师承制，都倡导或坚持了技艺、规范和就业道德融为一体，注重示范与模仿、总结与交流。案例教育方法不仅体现在职医、职官教育之中，也体现在吏员训练和艺徒训练等方面。算学教育渗透于天文历算、冶炼铸造、纺织制器、赋税徭役、商贾买卖等职业技术教育之中，坚持联系生产、生活实际于始终。     

互相关测速虚拟仿真的实验方法

介绍利用相关技术对运动物体速度进行测量的原理和实验方法,通过相关测速实验装置及其软件操作界面的介绍,进一步阐明“软件即仪器”的思想。     

Outside school time: an examination of science achievement and non-cognitive characteristics of 15-year olds in several countries

Elementary and secondary students spend more hours outside of class than in formal school and thus have more time for interaction with everyday science. However, evidence from a large international survey, Program of International Student Assessment (PISA) (OECD 2012), found a negative relationship between number of hours attending after-school science and science assessment scores in many countries, raising questions about why. The secondary analysis of the 2006, 2009, and 2012 PISA surveys found that in most Western countries the longer students attended after-school science programs (in a typical week), the lower their PISA standardized science test score, but the higher their positive attitudes toward future science careers, interest in science, and self-confidence in science. Several potential hypotheses for this relationship are examined and rejected. Further analysis of a causal relationship between frequent attendance in after-school programs and student achievement and attitudes should clearly identify the content of the program so that the analysis could distinguish experiences closely related to regular school curricula from the informal science activities that are not. A new analysis also should include carefully designed longitudinal surveys to test the effectiveness of informal experiences on later life choices in career and study.     

浅析偷税的认定

偷税是当前普遍存在的一种税务违法行为,应当具备主体、客体、主观和客观四要件,其中主观要件在理论和执法实践中最具争议性。依据偷税概念进行分析,从行为方式上讲,偷税本身均有主观故意的成分,因此,其主观方面也是故意的。从时间界限上看,认定偷税的时间界定应当是法律规定的申报期限。自查补报、虚开发票和认定偷税的时间界限等是执法工作中分歧较大的几个具体问题,研究认定自查补报是一种偷税行为,对虚开发票的行为人,只能按发票违法进行处罚,核定征收不能认定为偷税行为。     

无声语言在体育教学中的作用

根据以往的教学经验,对无声语言的特点,以及无声语言如何在体育教学中运用进行了分析。重点剖析了在体育教学中时空感、眼神、目光、表情、站立姿势和手势等几种无声语言的巧妙运用,从而加强教师和学生之间的交往,提高教学效果。