Time-on-task, technology and mathematics achievement

Information and communication technologies hold much promise for use in education in developing countries. This study reports on an evaluation conducted on the introduction of computers in the delivery of the mathematics curriculum in one of the provinces of South Africa. Although the request was for an outcome evaluation very early in the implementation of the program, it was tailored in such a way as to fulfill a more formative role. Despite substantial variability in implementation, and in most cases with very weak exposure of the learners to the intervention, sufficient evidence emerged to indicate that this mode of curriculum delivery may be effective. Improvement in mathematics performance was related to a range of variables: some concerned classroom teaching practices, some referred to social differences between the learners, and some to the specific intervention. The strongest of these predictors in the sample was the strength of the intervention: the more time learners spent on using the software to study mathematics, the more improvement they showed from 1 year to the next in their performance in the subject.     

Men's sexual health and the metabolic syndrome

The aim of this article is to provide an overview of the current literature on the impact of the metabolic syndrome on male sexual health and current developments in the management of sexually dysfunctional men with a metabolic syndrome. The increasing prevalence across the world of the metabolic syndrome-a cluster of cardiovascular disease risk factors-causes the metabolic syndrome to be considered the most important threat to male sexual health of the 21st century. It has been shown to have a negative impact on male sexual function through its relationship with cardiovascular disease risk, its association with hypogonadism, and associated psychosocial factors. Besides established pharmacological and hormonal interventions, lifestyle modification programs are considered important therapeutic tools.     

Family Loyalty and Adolescent Problem Behavior: The Validity of the Family Group Effect

Erratum . Journal of Law and Society Volume 32 Issue 3 The present study examined the relation between perceived justice and trust within family relationships and adolescent internalizing and externalizing problem behavior. Data were gathered from the father, the mother, and two of their adolescent children in 288 families. The social relations model was used to assess perceived justice and trust at the family level and the individual level. Adolescent internalizing and externalizing problem behavior turned out to be best predicted at the family level. Adolescents from families with less just or trustworthy climates showed more of these problem behaviors. Also associations between adolescent problem behavior and individual characteristics of the adolescents were found: adolescents who were generally viewed as less just/trustworthy were reported to have more problems. Our findings suggest that processes at different levels of family functioning (i.e., individual, whole‐family) should be taken into account when investigating associations between family characteristics and children's outcomes.     

A neural' network applied to tlie calculation of lyapunov exponents

Chaotic deterministics systems are characterised by the instability of orbits on an attractor. The largest Lyapunov exponent measures on average the exponential growth rate of small deviations along an orbit and gives as such an indication whether or not the dynamic generating process is unstable. The direct method for calculation of the Lyapunov exponent, based on finite differences as formulated by the so-called Wolf-algorithm,fails on medium sized data sets. Alternatively, one can use a neural network with backpropagation to estimate a data generating function. This so-calletl indirect method enables us to recover the theoretical value of the largest Lyapunov exponent in several examples.     

Gender differences in entrepreneurial intentions: A TPB multi-group analysis at factor and indicator level

Previous research suggests that diverse factors predict gender differences in entrepreneurial intent. Our paper integrates and expands on previous findings using the Theory of Planned Behavior (TPB), including the deeper-level measurement model, allowing for a better understanding of the origin of differences. The results of a survey with business students indicate that the effect of gender on entrepreneurial intentions is mediated via personal attitudes and perceived behavioral control but not social norms. More precisely, vis-à-vis their male counterparts, women are more driven toward entrepreneurship by motives to ‘get organized’ (balance) that are less dominant in predicting personal attitude. Moreover, female students are somewhat less driven toward entrepreneurship by beliefs of internal control that are more dominant in predicting perceived control. Finally, while female students are also more motivated to comply with normative role models, this did not influence their entrepreneurial intentions over and above perceived behavioral control and personal attitude. We discuss both practical and theoretical implications of our findings.     

From knowledge to decision – a case study of sales and operations planning in health care

One of the most important challenges in health care management is balancing resources with fluctuating and uncertain demand. This study examines whether introducing a standardised process for sales and operations planning at a large university hospital improved specialty department managers’ knowledge of planning conditions and if so, whether decisions were made based on this knowledge. Using responses from a survey of 30 specialty department managers at Sahlgrenska University Hospital in Sweden, the analyses indicate that operational knowledge strengthens insights about the needs for strategic decisions, and vice versa. Moreover, knowledge is a necessary, but not sufficient, condition for making decisions at the department level. An overall planning and decision structure is required and should be implemented first at the hospital level to effectively allocate resources.     

“如实述说”：逻辑中的信息流动

本文把逻辑表述为关于信息流动的一般理论，它涉及推理、观察和社会交往等人类能力。由此导致的多主体动力学可以用关于信息更新的动态认知逻辑系统来加以研究，后者也能够处理信念更新和学习问题；可以把这种语义动态学与作为信息阐明的推理的语法过程相结合：本文最后讨论了如何（将已有结果）扩展到主体之间的长期互动，并描述了（主体的）偏好和目标，以及由此导致的逻辑、博弈论和社会选择理论之间的相互作用。     

Worlds apart,worlds together: converging and diverging frames in climate and energy governance

This paper argues that past research has overlooked how the way problems and solutions are framed contribute to a prevailing gap in the global governance of climate and energy. Empirically, this paper investigates the frames of energy and climate change as expressed in key documents from the International Panel on Climate Change (IPCC) and International Energy Agency (IEA). Partly in contrast to past research, this paper finds (1) that there is a growing similarity in how the IPCC and IEA frame climate and energy; (2) that the IEA has gone from ignoring to acknowledging climate change and the transformation to a low-carbon energy system; and (3) that there is a prevailing difference in emphasis, whereas the IPCC only marginally discuss energy, while the IEA is still mainly talking about energy needs and fossil fuels even if climate change and renewables have entered their agenda.