Preparation for practice--developing and assessing DipSW students' pre-placement competence 1

Social work enters the twenty-first century in very different circumstances to those which have prevailed through the major period of its development. We are now in an era that has been characterised as that of 'post-welfarism'. Using recent theories that focus on the ideological and structural aspects of the social changes within which contemporary social work is developing, this article examines the impact and implications of such changes for social work education. Some conclusions are drawn for a critical approach to thinking about the content and process of professional education.     

Risk Characterization for Nanotechnology

Nanotechnology is a broad term that encompasses materials, structures, or processes that utilize engineered nanomaterials, which can be defined as materials intentionally designed to have one or more dimensions between 1 and 100 nm. Historically, risk characterization has been viewed as the final phase of a risk assessment process that integrates hazard identification, dose‐response assessment, and exposure assessment. The novelty and diversity of materials, structures, and tools that are covered by above‐defined “nanotechnology” raise substantial methodological issues and pose significant challenges for each of these phases of risk assessment. These issues and challenges culminate in the risk characterization phase of the risk assessment process, and this article discusses several of these key issues and approaches to developing risk characterization results and their implications for risk management decision making that are specific to nanotechnology.     

Forecasting the market demand for waste paper

In a recent article in this journal, Livesey and Barcena supplied an interesting but necessarily superficial analysis of the market for waste paper. Their essential conclusion was that, faced with future shortages, and hence increased prices of wood pulp, the paper and board industry would be forced to rely more heavily on secondary fibre. In turn, they felt that ‘in order to ensure an adequate supply of waste paper, governments may need to exert a greater degree of influence over the market than they do at present’.This paper seeks to provide a more rigorous analysis of the ‘waste paper problem’ in terms of future demand and fluctuations in that demand. It also corrects some misconceptions in the paper by Livesey and Barcena as to the likely sources of future supply and the economics of securing those supplies.     

Max-stable processes for modeling extremes observed in space and time

Max-stable processes have proved to be useful for the statistical modeling of spatial extremes. For statistical inference it is often assumed that there is no temporal dependence; i.e., that the observations at spatial locations are independent in time. In a first approach we construct max-stable space–time processes as limits of rescaled pointwise maxima of independent Gaussian processes, where the space–time covariance functions satisfy weak regularity conditions. This leads to so-called Brown–Resnick processes. In a second approach, we extend Smith’s storm profile model to a space–time setting. We provide explicit expressions for the bivariate distribution functions, which are equal under appropriate choice of the parameters. We also show how the space–time covariance function of the underlying Gaussian process can be interpreted in terms of the tail dependence function in the limiting max-stable space–time process.     

Book Reviews and Book Notes

The authors provide an overview of children's books published in the United States during the last decade (2000–2010) that deal with Mexico and Mexican people. Suggested guidelines for selecting quality books and a list of award-winning titles are included as resources for teaching about Mexico.