Subjective Difficulty of Movements With Ongoing Visual Control

Objective difficulty of a single-component visually controlled movement may be defined by Fitts's (1954) Index of Difficulty, which is a measure of difficulty in the sense that movement time is linearly related to the objective measure. For movements that have multiple components, it becomes difficult to determine an objective measure of task difficulty due to unknown interactions between components of the movement and interactions with other factors. Thus, it may be necessary to use indirect methods for allocating a measure of task difficulty. The purpose of the study was to determine whether participants could validly construct a subjective measure of the movement difficulty and whether this measure was related to the known objective measure of difficulty. Experiments showed that for single-component movements, there was a close relationship between measures of subjective and objective difficulty. With two-component visually controlled movements it was found that subjective difficulty could be related to objective difficulty, but not as simply as for single-component tasks.     

Effect of Instructions Prioritizing Speed or Accuracy on Kinematics and Kicking Performance in Football Players

The authors' purpose was to investigate if there is a speed accuracy trade-off in soccer kicking by using instructions prioritizing velocity, accuracy, or both upon soccer kicking performance and kicking direction in experienced soccer players. In addition, kinematics were measured to investigate the eventual differences in performance. Thirteen experienced male footballers performed penalty kicks with different instructions prioritizing velocity, accuracy or both. Three-dimensional kinematics, together with maximal ball velocity and hitting accuracy, were measured on all kicks. The main findings were that when the main aim was accuracy, accuracy increased, while the velocity reduced, which supports Fitts' law (Fitts, 1954 Fitts, P. M. (1954). The information capacity of the human motor system in controlling the amplitude of movement. Journal of Experimental Psychology, 47, 381–391.[Crossref], [PubMed] , [Google Scholar]). In addition, kicking accuracy was higher when kicking to the contralateral side. The slower ball velocity was caused by lower segmental and in run velocities. These lower segmental velocities were mainly caused by the lower maximal knee extension and pelvis rotation during the accuracy priority kicks.     

The Cascade Neural Network Model and a Speed-Accuracy Trade-Off of Arm Movement

We propose a hybrid neural network model of aimed arm movements that consists of a feedforward controller and a postural controller. The cascade neural network of Kawato, Maeda, Uno, and Suzuki (1990) was employed as a computational implementation of the feedforward controller. This network computes feedforward motor commands based on a minimum torque-change criterion. If the weighting parameter of the smoothness criterion is fixed and the number of relaxation iterations is rather small, the cascade model cannot calculate the exact torque, and the hand does not reach the desired target by using the feedforward control alone. Thus, one observes an error between the final position and the desired target location. By using a fixed weighting parameter value and a limited iteration number to simulate target-directed arm movements, we found that the cascade model generated a planning time–accuracy trade-off, and a quasi–power-law type of speed–accuracy trade-off. The model provides a candidate neural mechanism to explain the stochastic variability of the time course of the feedforward motor command. Our approach also accounts for several invariant features of multijoint arm trajectories, such as roughly straight hand paths and bell-shaped speed profiles.     

Identical Twins,Deduction Theorems,and Pattern Functions: Exploring the Implicative BCSK Fragment of S5

We recapitulate (Section 1) some basic details of the system of implicative BCSK logic, which has two primitive binary implicational connectives, and which can be viewed as a certain fragment of the modal logic S5. From this modal perspective we review (Section 2) some results according to which the pure sublogic in either of these connectives (i.e., each considered without the other) is an exact replica of the material implication fragment of classical propositional logic. In Sections 3 and 5 we show that for the pure logic of one of these implicational connectives two – in general distinct – consequence relations (global and local) definable in the Kripke semantics for modal logic turn out to coincide, though this is not so for the pure logic of the other connective, and that there is an intimate relation between formulas constructed by means of the former connective and the local consequence relation. (Corollary 5.8. This, as we show in an Appendix, is connected to the fact that the ‘propositional operations’ associated with both of our implicational connectives are close to being what R. Quackenbush has called pattern functions.) Between these discussions Section 4 examines some of the replacement-of-equivalents properties of the two connectives, relative to these consequence relations, and Section 6 closes with some observations about the metaphor of identical twins as applied to such pairs of connectives.     

Distress,Loss, and Adjustment Following the Birth of a Baby: A Qualitative Exploration of One New Father's Experiences

In contrast with the vast literature on the postnatal psychological difficulties experienced by some mothers, there have been few attempts to study the mental health of fathers in and around the time of the birth of a baby. Using an interpretive phenomenological analysis, this study attempts to map the experience of fathers following the birth of a child. A male consultation group was employed to guide the study, and the results feature an in-depth analysis of one new father. The findings were consistent with Kelly's notion of constructs of transition in revealing powerful emotional themes regarding loss and difficulties with adjustment. These are explored within the context of contemporary fathering, relational patterns, and male identity. The findings suggest that men's experience of distress may be linked to prevalent yet contradictory discourse directly linked to expectations about their roles following childbirth. They also suggest the clinical importance of this area, as men's well-being appears to impact that of the mother and baby.     

Mental Health, Social Environment and Sexual Risk Behaviors of Adolescent Service Users: A Gender Comparison

We examined individual mental health problems (depression, conduct disorder, and substance abuse) and social environment (family, peer, and neighborhood) factors associated with the sexual risk behaviors of male and female adolescents. Interviews with 778 adolescents, aged 14 to 18, showed that both mental health problems and social environment were related to adolescents' involvement in sexual risk behaviors. Conduct disorder symptoms, substance abuse or dependence symptoms, and the interaction between peer misbehavior and neighborhood problems were significantly associated with risky sexual behaviors. Peer misbehavior was a particularly strong factor related to sexual risk behaviors for youths who lived in neighborhoods with multiple problems. The only gender differences were found in age, with older males more likely to report engaging in high risk sexual behaviors. This study suggests the utility of multidimensional intervention strategies to deal with various adolescent problem behaviors, including risky sexual behaviors, within the context of their social environment.     

The Dimensional Nature of Externalizing Behaviors in Adolescence: Evidence from a Direct Comparison of Categorical,Dimensional, and Hybrid Models

Researchers have recognized the importance of developing an accurate classification system for externalizing disorders, though much of this work has been framed by a priori preferences for categorical vs. dimensional constructs. Newer statistical technologies now allow categorical and dimensional models of psychopathology to be compared empirically. In this study, we directly compared the fit of categorical and dimensional models of externalizing behaviors in a large and representative community sample of adolescents at two time points separated by nearly 2.5 years (N = 2027; mean age at Time 1 = 11.09 years; 50.8% female). Delinquent and aggressive behaviors were assessed with child and parent Child Behavior Checklist reports. Latent trait, latent class, and factor mixture models were fit to the data, and at both time points, the latent trait model provided the best fit to the data. The item parameters were inspected and interpreted, and it was determined that the items were differentially sensitive across all regions of the dimension. We conclude that classification models can be based on empirical evidence rather than a priori preferences, and while current classification systems conceptualize externalizing problems in terms of discrete groups, they can be better conceptualized as dimensions.     

The Development of Prosocial Behaviors in Young Children: A Prospective Population-Based Cohort Study

Researchers know relatively little about the normative development of children's behaviors aimed at alleviating distress or discomfort in others. In this article, the authors aim to describe the continuity and discontinuity in the degree to which young children in the general population are reported to exhibit specific prosocial behaviors. Data came from the Québec Longitudinal Study of Child Development. Consistent with Hay's model of prosocial development, the results show that there were about as many children who stopped exhibiting prosocial behaviors between 29 and 41 months of age as there were children who started doing so during this period. Further, gender differences (girls > boys) in prosocial behaviors are either emerging or at least increasing in magnitude, with girls being more likely to start and boys being more likely to stop exhibiting these behaviors between 29 and 41 months of age. Consistent with the early-onset hypothesis, children who exhibit prosocial behaviors at 17 months of age are less likely to stop exhibiting the same behaviors between 29 and 41 months of age. Otherwise, if they did not exhibit prosocial behaviors at 29 months of age, they are also more likely to start doing so in the following year.     

盲人的时间水平方向隐喻的通道特异性

通过2个实验, 考察了感觉通道对盲人的时间水平方向隐喻的影响。实验1发现, 盲人只在动作水平上存在同阅读方向一致的时间水平方向隐喻, 对表征过去的词或句子按左键反应和对表征将来的词或句子按右键反应时更快, 表明盲人用于隐喻时间的空间信息是知觉性的。实验2比较了明眼人可视组被试和明眼人遮眼组被试的时间空间隐喻, 发现明眼人可视组被试只在动作水平上存在时间水平方向隐喻, 明眼人遮眼组被试只在刺激在右侧时呈现才出现动作水平的时间水平方向隐喻。综合分析表明, 盲人和明眼人可视组被试的反应更为接近, 表明盲人的时间空间隐喻未受听觉信息的影响。盲人通过运动通道获得的空间认知代偿了视觉通道信息的缺失。     

透析器复用的医学、经济与法制思考

回顾透析器复用的历史并分析其复用现状,医学原因和经济学原因是透析器复用的基础,复用存在的医学和法律相矛盾问题,并分析透析器复用的标准和效果评价.从医学、法律、社会三个方面分析透析嚣复用的前景,认为透析器复用有利于患者和减轻社会压力,但是存在医疗风险,透析器的"单用比复用好,而复用比不用好".     

从母亲的敏感性到学步儿的依恋安全性：内部工作模式的桥梁作用

采用视觉习惯化实验程序、陌生情境技术及母亲行为Q分类方法对41名14个月的学步儿及其母亲进行了学步儿内部工作模式、学步儿在陌生情境中的依恋类型以及母亲在母婴互动中的敏感性的评估。结果发现：(1)不安全型的学步儿预期看护者对他们痛苦的信号是无回应的。(2)以自身为中心的母亲的学步儿预期看护者是无回应的。(3)潜类别分析的结果发现母亲敏感性影响学步儿依恋行为的2种关系模式：类别1, 以孩子为中心的母亲的学步儿更容易形成看护者是有回应的预期, 持这种预期的学步儿在陌生情境程序中表现出安全依恋行为; 类别2, 以自身为中心的母亲养育出的学步儿更容易对看护者形成无回应的预期, 并在陌生情境中表现出不安全依恋行为。研究表明：内部工作模式在母亲的敏感性和学步儿的依恋安全性之间起着重要的内部机制作用—— 母亲的敏感性行为的累积促进了学步儿内部工作模式关于母亲的预期, 这种预期又进一步引导着学步儿的依恋行为。     

互联网使用动机、行为与其社会-心理健康的模型构建

以581名大学生为被试,采用结构方程模型技术构建了互联网使用动机、病理性互联网使用行为与其相关社会-心理健康的关系模型。其中,互联网使用动机包括信息获取性动机和人际情感性动机两种模式;病理性互联网使用行为包括上网冲动性、分离/逃避和网上优越感三个初级因素;互联网相关社会-心理健康包括孤独感、社会参与度、一般抑郁、生活幸福感和生活满意度五个初级因素,并进一步概括为社会健康和心理健康两个维度。研究结果表明,基于信息获取性动机而使用互联网有助于相关社会-心理健康水平的提高;基于人际情感性动机而使用互联网更容易导致病理性互联网使用行为,并由此对使用者的社会-心理健康产生负面影响;大学生使用互联网的积极效应大于消极效应,且信息获取性动机对社会健康具有更大的积极效应,而人际情感性动机对对心理健康具有更大的消极效应     

Quantum Paradoxes, Time, and Derivation of Thermodynamic Law: Opportunities from Change of Energy Paradigm

Summary  Well known quantum and time paradoxes, and the difficulty to derive the second law of thermodynamics, are proposed to be the result of our historically grown paradigm for energy: it is just there, the capacity to do work, not directly related to change. When the asymmetric nature of energy is considered, as well as the involvement of energy turnover in any change, so that energy can be understood as fundamentally “dynamic”, and time-oriented (new paradigm), these paradoxes and problems dissolve. The most basic consequence concerns the particle-wave dualism. For a reversible inter-conversion of a particle into a wave, subject to a dynamic energy, a self-image of information has to be generated: quantum theory has to be complemented by a theory of information. Then, quantum processes can be derived from classical ones and the second law of thermodynamics with the tendency of increasing entropy follows in a straightforward way.     

临床护理人员的护理伦理知信行素养调查研究——以某三甲医院为例

为了解临床护理人员的护理伦理知识、信念、行为等素养的现状、存在的主要问题及其主要影响因素,问卷调查了某三级甲等医院的1147名护理人员,同时对16名资深护理人员和护理工作管理者进行深入访谈。调查结果显示,尽管多数护理人员在工作实践中能正确践行护理伦理行为,但护理人员的护理伦理知识欠缺,护理伦理教育有待加强;部分护理人员的基本护理（医学）伦理理念尚未建立;“重技术轻人文”的护理理念仍然是影响护理伦理践行的主要因素。临床护理人员普遍有接受有关护理伦理知识和技能培训的需求和愿望。

     

Natural Mentors, Mental Health, and Risk Behaviors: A Longitudinal Analysis of African American Adolescents Transitioning into Adulthood

Patterns of substance use are examined in a sample of over 1,200 youth in a non-metropolitan region of New England. Self-reported history and frequency of alcohol, tobacco, marijuana, inhalants, pain medications, and other hard drug use was assessed for 9th and 10th grade students. Latent class analyses identified four patterns of substance use: non-users (22%), alcohol experimenters (38%), occasional polysubstance users (29%), and frequent polysubstance users (10%). Contextual risk and protective factors in the individual, family, peer, and community domains predicted substance use patterns. Youth report of peer substance use had the largest effects on substance use class membership. Other individual characteristics (e.g., gender, antisocial behavior, academic performance, perceived harm from use), family characteristics (e.g., parental drinking, parental disapproval of youth use), and community characteristics (e.g., availability of substances) demonstrated consistent effects on substance use classes. Implications for prevention are discussed from a social-ecological perspective.     

孔、孟与管子德治思想之比较

孔子和孟子是先秦儒家最重要的代表人物,他们的思想中都有着丰富的德治内容。管子虽是早期法家的代表,但思想中同样具有德治的内容。孔、孟与管子在德治思想上有着很大的相似性,在惠民爱民、正名、正身率下、以民为本、善政措施、选贤任能等方面有着诸多的一致之处。但出于各自学派的立场,孔、孟与管子在德治与法治的关系、德治的目标与特征、德治的人性论的出发点等方面也存在着差异。     

5·12地震灾后四川和北京大学生价值观类型的对比

价值观作为社会意识形态的反映,会受到重大社会事件的影响。5·12汶川大地震以其突发性和巨大的破坏性特征成为影响价值观的可能因素之一。该研究以青年大学生为对象,以“价值观类型量表”为工具,关注地震后大学生价值观的变化特点,并对比北京、四川两地大学生价值观特点的异同。结果发现：1）灾后北京和四川两地大学生的价值观整体排住从高到低依次是：社会型、实用型、信仰型、科学型、政治型、审美型。2）社会型价值观已经成为大学生的主导价值观,且四川大学生更为重视。3）北京和四川大学生在震后的价值观系统均包含四个层次,其中在北京大学生的价值系统中,社会型是第一层次,实用型是第二层次,信仰型是第三层次,审美型、政治型和科学型合并为第四层次;而在四川大学生的价值系统中,社会型是第一层次,实用型和信仰型合并为第二层次,科学型是第三层次,政治型和审美型合并为第四层次。     

汉、蒙、哈民族初中生早期问题行为研究

本研究采用问卷法,以甘肃省652名汉族、蒙古族、哈萨克族初中生为样本,考察了民族初中生早期问题行为的特点及其与家庭教育的关系。结果显示,汉族聚居区的汉族初中生在早期问题行为的6个因子上均值均接近或超过"稍有问题"的临界值,为本研究中的各民族之首。与哈族、蒙族相比,汉族家教方式中存在的问题更多、更严重;与同少数民族杂居在一起的汉族比,汉族聚居区家长的家教方式中存在的问题更为严重。相关不当家教方式对初中生早期问题行为的影响效应非常显著。