State laws governing school physical education in relation to attendance and physical activity among students in the USA: A systematic review and meta-analysis

Background:This study systematically synthesized and quantified the relationship linking state laws governing school physical education(PE)to PE attendance and physical activity(PA)in class and throughout the day and week among students in the USA.Methods:A keyword search was performed in PubMed,Web of Science,Cumulative Index to Nursing and Allied Health Literature(CINAHL),Academic Search Complete,and EconLit.Meta-analyses were performed to estimate the effects of state PE laws.Results:A total of 17 studies were included in the review,and five contributed to the meta-analyses.A total of 8 studies used nationally representative school-or student-level data,three focused on multiple states,and the remaining six examined the PE laws of a single state.The presence and strength of state PE laws were positively associated with PE attendance and the frequency and duration of PA during PE classes and throughout the school day.Compared to those residing in states with weak or no PE laws,students in states with strong PE laws had an additional 0.2 days(95%confidence interval(95%CI):0.10.4)of PE attendance per week and spent an additional 33.9 min(95%CI:22.745.0)participating PE classes per week.State PE laws affected girls’PA more than boys’.Different aspects of state PE laws tended to affect students’PE attendance differently.Disparities in the implementation of state PE laws existed across schools.Conclusion:Future studies should adopt objective measures on PE and PA participation and examine the roles schools and districts play in mediating the effect of state PE laws on students’PE attendance and PA.

A numerical study of comparison of two one-state-variable,rate-and state-dependent friction evolution laws

The two one-state-variable, rate- and state-dependent friction laws, i.e., the slip and slowness laws, are com- pared on the basis of dynamical behavior of a one-degree-of-freedom spring-slider model through numerical simulations. Results show that two （normalized） model parameters, i.e., A （the normalized characteristic slip distance） and β-α （the difference in two normalized parameters of friction laws）, control the solutions. From given values of △, β, and α, for the slowness laws, the solution exists and the unique non-zero fixed point is stable when △〉（β-α）, yet not when △ 〈（β-α）. For the slip law, the solution exists for large ranges of model parameters and the number and stability of the non-zero fixed points change from one case to another. Results suggest that the slip law is more appropriate for controlling earthquake dynamics than the slowness law.

United States Law on the Protection of Abused and Neglected Children

I. Introduction This paper discusses child protection in the United States. I will discuss four general topics. The first topic is United States laws on the protection of children from child abuse and neglect. The second topic is providing care for children who must be removed from their homes. The third is the role of courts in child protection in the United States.

Perception of Abortion and Abortion Laws by Lawyers in Anambra State Nigeria

Abortion is the knowing destruction of the life of an unborn child in the womb other than for the principal purpose of producing a life birth or removal of a dead tissue. The Nigeria law stipulates that abortion is allowed only where there is risk to the life of the woman and or to her physical or mental health. This study is aimed at determining the perception of abortion and the relevant laws by lawyers in Anambra State, Nigeria. It is a descriptive cross sectional study carried out between May-June 2010 using pre-tested self administered questionnaires to collect data from consenting 200 lawyers in the 3 major towns of Anambra State. All the respondents knew about abortion, recognized health hazards associated with it and mentioned infertility as the major complication of abortion (53%) followed by death (52.5%) and bleeding (42.5%). About 80% of respondents said abortion should be allowed in cases of danger to woman’s life, rape or incest. Eighty-five percent of the lawyers were aware of the existing abortion law in Nigeria and 76.5% of this knew abortion was legal only to save the life of the woman. Only 26% were in support of legalization of abortion. The Lawyers recommended health education and family planning, among others as means of preventing abortion and its complications. Stigma associated with abortion should be removed to improve free reporting of abortion cases for legal actions. Further research should involve other stakeholders on abortion to make for a holistic approach to the problem.

The Natural Law of Transition of a Charged Particle into a Compound State under the Action of an Electroscalar Field

This article is the continuation of article [1] where the experimental facts of observation of the electroscalar radiation in the spectrum of the Sun have been presented [2]. This radiation comes into the world having a long wavelength, being longitudinal and extraordinarily penetrating. In accordance with the principle of least action, the Lagrangian of the electroscalar field and the tensor of energy-moment are determined using the variation the potential and coordinates. The equation of motion the charged particle in electroscalar field is determined and the energy of particle has the negative sign with respect to the mechanical energy of particle and the energy of electromagnetic field. So, this is decreasing the electrical potential of particle during the propagation. The electroscalar energy of charged particle and field’s force acting on the particle during their motion change the particle’s electrical status which, in its turn, may trigger the transition of the particle into a compound state during interaction with any object. Due to the continuity this process can lead the particle to the state which enters into a compound state with a negative energy for a different particle’s velocity. This state is the physical vacuum’s state. Analysis of the solar spectrum demonstrates that scattering and absorption of electroscalar wave go on the cavities of solids. The spreading out of electroscalar field obeys to the law of plane wave and the transfer the energy and information can occur in vacuum and any medium.

一体化与统纪化:“儒法国家”,抑或大国礼治?

“儒法国家”作为概括中国秦汉以后政治系统特质的既有模式,没有充分估量礼治对于中国国家结构的奠基意义,易于呈现为古今断裂的历史政治叙事。周礼所开启的中心统合主义原理展现为一体化与统纪化。一体化包含了统治权力一体化、族群伦理一体化、家国经济一体化,由周礼中的分封、宗法和井田开其端,深刻影响了郡县大一统的制度体系。统纪化是指礼治秩序精神的历史性延续,分别呈现为生统、宗统和治统,三统相系相维而不断推进一体化进程。正是大国礼治所展现出的一体化和统纪化,使我们在面临秩序危机的时候赓续了大一统国家的基本结构,在进一步推进族群、经济和治理层级深度融合的进程中完成了文明古国的现代转化。

湖北宜昌磷矿伴生稀土元素分布规律、赋存状态及其开发利用前景分析

【研究目的】湖北省宜昌磷矿中伴生有稀土元素,研究其分布规律及赋存状态,对稀土元素的回收利用具有重要意义,其作为伴生矿产的综合利用将成为未来稀土矿的重要来源。【研究方法】本文以含稀土磷块岩为主要研究对象,在系统取样的基础上,开展岩矿鉴定、全岩地球化学分析、XRD衍射分析、SEM观察、LA-ICP-MS测试等工作。【研究结果】磷块岩中稀土元素总量ΣREE+Y为63.5×10^(-6)~271.8×10^(-6),不同层位或不同岩性的磷块岩中稀土元素含量有所差异。【结论】稀土元素含量受岩性控制明显,由白云岩→白云质磷块岩→致密块状磷矿石→泥质条带磷块岩→泥岩,含量逐渐升高。微量元素反映出宜昌磷矿的古气候以干热为主,西北部略表现出温暖湿润特点;Ce异常、V/Ni和Y/Ho比值反映海水中EH条件从底部到顶部,即从Ph22成磷期到Ph13成磷期,形成水体环境逐渐氧化。宜昌磷矿中稀土元素总量整体较低,且泥岩较磷块岩中含量高,表明吸附态稀土较类质同象稀土含量高。宜昌伴生稀土磷矿资源丰富,利用合理的技术对稀土元素进行综合回收,对宜昌磷矿资源的合理利用和经济发展有重要意义。

一类不确定切换模糊系统的记忆保成本控制

针对一类具有状态时滞和不确定性的切换模糊系统,提出了该类系统的记忆保成本控制问题。利用引入系统过去的状态信息,构造有记忆状态反馈控制器,以消除系统时滞对于系统稳定性产生的不良影响。在保证成本函数指标小于某个上界及允许的不确定性条件下,结合多Lyapunov函数方法和线性矩阵不等式(linear matrix inequality,LMI)处理方法得到最终的充分条件,保证闭环系统能够渐近稳定;且得到满足设计的切换律的记忆状态反馈控制器增益。最后通过Simulink仿真验证了所提方法的正确性。

论经济法中的国家主体

经济法中的国家主体,具有不同于政府等主体的特殊性。基于经济宪法和经济法的相关规定,国家主体在经济法中具有独立地位,其经济职能的履行和经济职权的行使,应受经济宪法和经济法的约束,以体现国家理性的要求。此外,经济法中的国家主体在总体上是“现代国家”“经济国家”,并在经济法的各个部门法中具体体现为预算国家、税收国家、债务国家、规制国家等多种国家形态。研究经济法中的国家主体,应结合国家目的或国家目标、国家任务、国家职能、国家理性或国家理由等影响因素,分析具体的国家形态,由此有助于审视法律规定背后的法治原理和法治问题,揭示经济法制度中国家主体存续和发展的内在逻辑,并在法治框架下解决国家调制行为的合宪性、合法性问题,切实保障市场主体的合法权益。依循上述研究路径,有助于提炼经济法中的国家理论或国家主体理论,深化经济法学主体理论乃至整体总论的研究,推动经济法治和国家治理体系的完善。

违法建筑上合法权益的行政赔偿研究

违法建筑不为我国法律所认可,但其在强制拆除过程中存在部分符合我国法律规定的合法权益。违法强拆侵害行政相对人合法权益应予行政赔偿,赔偿范围包括可回收利用建筑材料、建筑材料的损失扩大、室内物品及行政相对人信赖利益损失。违法强拆侵害合法权益应予行政赔偿具有法理支撑,具体可从行政赔偿功能、以人为本的执法理念、行政赔偿归责原则及职务侵权行为的应责性四个方面证成。违法建筑认定绝对化、贵重物品举证难、赔偿惩戒性不足及赔偿执行难度大成为违法强拆行政赔偿的实践难题。为充分保障行政相对人合法权益,可从综合考虑认定违法建筑、做好拆除证据收集、增强赔偿惩戒性及对赔偿义务机关依法强制执行等方面探索完善行政赔偿的路径。

美国“犯罪”观念对英国普通法的传承与超越

犯罪观念不仅是刑法学科的问题,也是国家历史的一个组成部分。英美法系以判例法为主,重视经验和实用,因此两国至今未能颁布一部成文且统一的刑法典而对“犯罪”作出一致表述。美国作为英国的前殖民附属地,自然继承了普通法上的“犯罪”观念,这在犯罪的分类、构成要件和影响因素等方面均有所体现。而美国自独立战争胜利后制定的联邦宪法,助力其在刑法领域的改革与发展。从历史的角度来分析社会现象之一的犯罪,有助于我们把握美国各历史阶段下犯罪与宗教、道德、政权、经济之间的互动关系,探究美国独立后区别于英国普通法下犯罪观念的成果。

论公司法规制国家出资公司的口径与路径

新修订的公司法增加了第七章“国家出资公司组织机构的特别规定”,实现公司法对国家出资公司的规制体例编排“从节到章”、条款数量“从少到多”以及适用范围“从国有独资到国家出资”的重要进步,相当程度上克服了原公司法中存在的规制理念陈旧、口径局限、路径紊乱等缺陷。但新公司法仍存在规制口径模糊、组织规范制度供给不足等痼疾,需要进一步校准国家出资公司的规制口径,将国有独资公司的全资子公司纳入其中,保证规制逻辑的周延性;继续改进规制路径与立法技术,通过引致技术简化关联部门法的重复性规定,增加具有制度特色的治理规则供给,包括完善党组织条款,细化外部董事条款,鼓励并引导国有控股公司章程设置赋权性的差异化治理条款,以提升公司法的适应性品格。

个人信息出境的国内法规制路径及体系化完善

数字化个人信息的大规模跨境传输使得个人权益、公共利益和国家安全利益受损的风险加剧,国际社会尚未达成统一法律规范予以应对。为维护国家数据主权、促进数据产业发展与保障个人信息安全,各国选择以国内法规制的方式对个人信息出境予以监管,具体表现为国家专门立法、联盟统一立法与国家分散立法。我国通过专门立法规制个人信息出境,形成了“硬性”与“软性”两轨监管机制,但存在分轨监管内容交叉、公私共治监管尚未形成的问题,阻碍个人信息的安全出境。在统筹推进国内法治和涉外法治的背景下,我国应以系统观念加强个人信息出境监管建设,从主体上发挥公私体系的协同性,从规范上强化攻防体系的均衡性,从空间上增进内外体系的互动性,为促成个人信息跨境规制的多边共识贡献中国智慧。

非理想炸药水中爆炸载荷相似律数值仿真

为研究不同尺度非理想炸药水中爆炸载荷的相似性,采用LS-DYNA软件的S-ALE算法,构建了基于JWL-Miller状态方程描述的非理想炸药水中爆炸载荷数值计算模型;利用典型试验数据对计算模型参数进行了标定,匹配设置了典型RDX基非理想炸药的JWL-Miller状态方程参数;通过不同尺度炸药在不同水域环境条件下的爆炸过程模拟,分析了爆炸载荷特征参数的相似性。结果表明,影响非理想炸药水中爆炸冲击波压力峰值相似律的主要因素是其自身的非理想特性;水域环境因素(如自由面及静水压力梯度等)会对气泡脉动周期与半径的相似律产生较大影响。对于15%允许误差范围的工程仿真而言,0.53~5.30 m/kg 1/3比例距离(约10~100倍炸药半径)范围内,非理想炸药自由场水中爆炸载荷参数相似律可近似满足,与理想炸药的相似律特征基本一致,工程可用。基于JWL-Miller状态方程统一参数描述的非理想炸药默认其后燃反应是稳定且完全的。在实际中,由于水下非理想炸药受到复杂的化学反应动力学的控制,几何尺寸效应仍有可能导致非理想成分释能过程的较大差异,因此,精细化数值仿真需要针对不同比例距离或不同尺度模型来匹配不同的Miller模型参数,爆炸载荷相似律也可能在更有限的尺度范围内成立。

理想气体焦耳定律与物态方程的关系

焦耳定律作为理想气体的能态方程,是热力学一般能态方程在理想气体物态方程约束下的特殊解,本质上不独立于物态方程.但焦耳定律却是理想气体温标等于热力学温标的充分必要条件,以理想气体温标表述理想气体定义时,物态方程和焦耳定律缺一不可.

基于对数型障碍Lyapunov函数的俯仰驾驶仪设计

相控阵雷达制导拦截弹在拦截高速大机动目标时,弹体气动参数剧烈非线性变化影响控制系统对大攻角的响应效果,应设计考虑攻角指令跟踪误差约束的鲁棒自动驾驶仪控制律。基于双幂次趋近律和对数型障碍李雅普诺夫函数设计了鲁棒非线性自动驾驶仪控制律,可将攻角指令的跟踪误差快速收敛于约束范围内。通过降阶扩张状态观测器对系统中存在的气动参数不确定性和系统外部扰动进行在线估计和补偿。稳定性分析和数值仿真表明,攻角可在1 s内达到稳态且攻角响应的稳态误差<10-4°,所提出的自动驾驶仪控制律具有较强的鲁棒性,能够准确稳定地跟踪攻角指令,控制导弹产生所需过载进而精准拦截目标。

临界状态土的物理标度律

土的临界状态理论描述了土有效应力、抗剪强度与土密实度之间的对应关系,大量土力学试验还揭示了土体强度与加载速率存在相关性。考虑到颗粒物质是自然土体的实际载体,从颗粒物理本源出发,将流态颗粒惯性数I发展为考虑砂土密实程度(即初始颗粒体积分数Ф0)的准静态颗粒物理惯性数Q=Ф0[ln(I)+α]。以砂土的经典三轴试验数据为基础,探究了处于临界状态土的颗粒物理标度律,发现颗粒的摩擦系数μ与准静态颗粒惯性数Q之间满足简单的μ=ξQ线性关系。新建立的简单物理标度律能够统一刻画处于临界状态砂土的密实状态、剪切速率、围压和粒径等因素与土内摩擦角间复杂的经验关系。为描述受剪颗粒准静态变形的体变规律,进一步探索了临界状态下土颗粒体积分数与准静态颗粒惯性数间的相关性。对三维应力状态情况,引入一个新的无量纲量“中主应力数”对标度律进行拓展,可揭示中主应力对临界状态砂土摩擦特性的影响。

晚清国家翻译的海外实践——以“法政丛编”编译为例

晚清留日学生组织湖北法政编辑社编译出版了中国近代第一套大型法政丛书——“法政丛编”。本文基于国家翻译理论,对“法政丛编”的编译动因、文本特点和实践特征进行了研究。研究发现,“法政丛编”编译受晚清改良法律、营办新学、奖励游学等因素的驱动,呈现出翻译环境优越、译者资源集聚、语言文化邻近等特征,但同时也存在翻译组织具有临时性、管理体系较为松散、资源配备有限等局限性。“法政丛编”丰富了我国国家翻译实践的类型,对之加以深入探究有助于推动新时代国家翻译理论和实践的发展。

基于自适应H_(∞)观测器的锂电池SOC与容量联合估计

为了提高锂电池SOC的估计精度,提出了一种基于自适应H_(∞)观测器的锂电池SOC与容量联合估计方法。基于锂电池的二阶RC等效电路模型,并考虑SOC和容量的耦合关系,将容量也作为系统的状态变量进行观测。设计了一种自适应H_(∞)观测器,其参数可随锂电池状态的变化自适应调整。由于在SOC估算时考虑了容量的影响,实现了SOC和容量的同时准确估计。实验结果表明:自适应H_(∞)观测器的估计精度高且鲁棒性强,电池的SOC平均估计误差始终保持在±0.43%以内,相比于EKF和H_(∞)观测器有更高的估计精度与稳定性。

基于TNESO的PMSLM分数阶自抗扰控制

线性自抗扰控制(LADRC)以结构简单、易于实现且抗干扰能力强的特点在永磁同步直线电机(PMSLM)中得到广泛应用,但电机启动和负载突变会导致LADRC系统中的线性扩张状态观测器(LESO)扰动估计精度下降。为此,提出一种基于时变增益非线性扩张状态观测器(TNESO)的PMSLM分数阶自抗扰控制策略。结合LESO和非线性扰动观测器(NDOB),并根据误差与增益的关系构建动态增益函数,设计新型状态观测器TNESO;在此基础上,以分数阶PDμ控制律代替线性状态误差反馈控制律(LSEF),建立改进型自抗扰速度控制系统,以进一步提高电机控制的实时性和鲁棒性。仿真与实验结果表明:所设计的速度控制系统可以有效减少直线电机启动、负载突变时的观测响应时间,抑制观测初始时刻扰动峰值,从而满足高性能的PMSLM速度控制要求。