On the Number of Cycles in Randomly Selected Permutations

In this article we derive the distribution, mean and variance of the number of cycles in a randomly selected permutation of the first n integers.     

Learning organic chemistry through natural products

Chemical methods to determine the conformations and absolute configurations of menthol, a cyclohexane derivative with 3 chiral centres, are described.     

Learning organic chemistry through natural products

Some interesting examples of the linkage between the structure and biological function of secondary metabolites in plants and animals are described.     

Reclaiming Kindergarten: Part II: Questions About Policy

Part II of “Reclaiming Kindergarten” continues the discussion related to responding to the crisis in today’s kindergarten. In Part II, two policy questions are posed, the answers to which seek to respond to this continuing crisis. The questions center on issues related to engaging families in kindergarten and the need to consider a new early childhood paradigm where kindergarten is part of a continuous and seamless educational experience spanning prekindergarten through third grade. As in Part I, examples of classroom practice are used to illustrate the effective implementation of these principles in a kindergarten classroom.     

Classroom behavior of children and adolescents with learning disabilities: a meta-analysis

Meta-analysis was used to review the results of 25 studies that compared the classroom behavior of children and adolescents with learning disabilities (LD) to children without learning disabilities. The data were analyzed from several different methodological perspectives. Results showed that both methodologically strong and weak studies demonstrated significant behavioral deficits of children with learning disabilities compared to their nondisabled peers in each of five overall areas: on-task behavior, off-task behavior, conduct disorders, distractibility, and shy/withdrawn behavior. Both observational and teacher rating data demonstrated these differences. Effect sizes for both groups of studies seemed to cluster around 1 standard deviation, suggesting noticeable and educationally significant impairment in the behavior of children with disabilities. Analysis of grade-level effect sizes suggests some explanation for the large number of referrals often witnessed during the elementary school years. Educational implications of these behavioral differences in terms of implications for mainstreaming are discussed.     

The expert witness in child abuse and neglect: An interdisciplinary process

The legal system is an important part of a society's response to child abuse and child neglect. Courts need to be guided in their deliberations by experts from many different professions. Consultation and in-court expert testimony is necessary from medicine, psychology, psychiatry, social work and other professions both to prove child abuse and neglect and establish the power of the court to act on behalf of a child but also to guide the court in the intervention strategy most suited to the needs of the child and his family. Non-lawyers often feel uncomfortable in the legal setting. The adversary process is foreign to their training and professional experience. Collaboration with a lawyer greatly improves their effectiveness in court. Lawyers, on the other hand, need to make maximum use of medical and social-psychological experts in the court process in the interests of their clients; but to do so lawyers need a basic understanding of the other professions. With an emphasis on a process of mutual education, the paper presents a framework for collaboration between lawyers and expert witnesses in child abuse and neglect cases. “Expert witness” is defined; informal consultation is encouraged; suggestions for selecting a collaborator are made; initial contracts between lawyer and expert, case conferencing and preparation for trial are discussed; specific advice on direct and cross examination is provided.     

Preservice teachers’ use of contrasting cases in mathematics instruction

Drawing comparisons between students’ alternative solution strategies to a single mathematics problem is a powerful yet challenging instructional practice. We examined 80 preservice teachers’ when asked to design a short lesson when given a problem and two student solutions—one correct and one incorrect. These micro-teaching events were videotaped and coded, revealing that fewer than half of participants (43%) made any explicit comparison or contrasts between the two solution strategies. Those who did were still not likely to use additional support strategies to draw students’ attention to key elements of the comparison. Further, correlations suggest that participants’ mathematical content knowledge may be related to whether participants’ showed contrasting cases but not to whether they used specific pedagogical cues to support those comparisons. While these micro-teaching events differ from the interactive constraints of a classroom, they reveal that participants did not immediately orient toward differing student solutions as a discussion opportunity, and that future instruction on contrasting cases must highlight the utility of this practice.     

A review of social interventions for students with learning disabilities

Twenty-two studies are reviewed that report the effects of social skills training and intervention with 572 children identified as learning disabled between 5 and 19 years of age. These studies are reviewed to examine characteristics and components of intervention effectiveness. Age and sex of subjects, grade grouping, group size, intervention duration, intervention procedures, subject selection, and type of interventional model are examined to find patterns that reflect intervention success. Several intervention characteristics and components are associated with social intervention effectiveness: selecting subjects who had social skills difficulties or low peer acceptance, using cognitive-behavioral intervention procedures, providing individual or small group instruction, and applying long-term intervention and training. Discussion focuses on difficulties in comparing studies to determine intervention effectiveness through the examination of outcome measures, a call for revisions in future reporting of social interventions in the literature, and those intervention factors that relate to increases in peer acceptance.     

Photoresists for microlithography

Photoresist technology, which is used for micro-patterning exploits changes in properties of polymeric materials, such as their solubility or volatility, upon photo-irradiation. This process has greatly benefitted from the knowledge base of organic chemistry and photo-induced organic transformations. The role of chemistry in the development of photoresists is described in this article.