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For the TREC 2007 conference, the CRM114 team considered three non-Bayesian methods of spam filtration in the CRM114 framework - an SVM based on the "hyperspace" feature==document paradigm, a bit-entropy matcher, and substring compression based on LZ77. As a calibration yardstick, we used the well-tested and widely used CRM114 OSB markov random field system (basically unchanged since 2003). The results show that the SVM has a spam-filtering accuracy of about a factor of two to three better accuracy than the OSB system, that substring compression is somewhat more accurate than OSB, and that bit entropy is somewhat less accurate for the TREC 2007 test sets.

The electrical properties of the mismatched interface between InP and GaP have been investigatedted. High resolution transmission electron microscopy (HRTEM) image shows the presence of strain relieving, 90° misfit dislocations at the InP/GaP interface. Electrochemical capacitance voltage (ECV) profiling indicates the presence of a high-density sheet of carriers at the interface. AFM image shows a pretty good InP epitaxial layer with surface roughness of 2.48 nm has been obtained. A model based on Fermi-level pinning in InP at the interface by misfit dislocations is proposed to account for the observed electrical behavior.

Discussions of diagnostic tools that gauge students' conceptual understanding permeate the literature. Many instructors report their class' normalized gain to characterize the change in scores from pre-test to post-test. We describe a new procedure for characterizing these changes. This procedure, which we call the normalized change, c, involves the ratio of the gain to the maximum possible gain or the loss to the maximum possible loss. We also advocate reporting the average of a class' normalized changes and utilizing a particular statistical and graphical approach for comparing average c values. © 2007 American Association of Physics Teachers.

Introduction Communication deficits are one of the core symptoms of autism spectrum disorders (ASDs). People with ASD can be slow to begin talking, or may not learn to talk at all; others may learn to produce words and sentences but have difficulty using them effectively to accomplish social interactive goals. In this chapter we will discuss the course of the development of communication in ASD and will outline how communication deficiencies in this population are identified and treated. Before we do, however, we should be clear about three important terms we will be using, which are illustrated in Figure 4.1. The term “communication” is the broadest of this trio. It refers to all forms of sending and receiving messages, not only with language, but in other ways, such as with gestures, body language, even the way we dress. Animals can also communicate by means of their vocalizations to alert others to danger, for example. That's why the largest circle in Figure 4.1 represents communication. Within the realm of communication, language represents a specific type, so it is enclosed within the larger circle of communication in the figure. Language involves the creation of a potentially infinite set of never-before-conveyed messages through the combination of words in rule-governed ways that allow the formation of sentences to express meaning to others. © Cambridge University Press, 2007 and 2009.

We develop a model of sequential responses of disaster survivors as they experience natural disaster stages. The disaster response model is based on the confluence of psychological processes with temporal environmental states that are markers of disaster periods. The study analyzes journalistic narratives taken from informants experiencing natural disasters in two culturally diverse communities. Recorded short-term vivid memory traces of survivors are assumed to accurately project their interpretations of events and experiences, reflected in their narratives. Whilst survivors share many similarities in their profiles of natural disaster response, some cultural differences in response are observed between communities, such as religiosity. Copyright © 2007 Massey University.

We have obtained and analyzed UBVRI CCD frames of the young, 4-10 Myr, open cluster NGC 3293 and the surrounding field in order to study its stellar content and determine the cluster's IMF. We found significantly fewer lower mass stars, M≤2.5M ⊙, than expected. This is particularly so if a single age for the cluster of 4.6 Myr is adopted as derived from fitting evolutionary models to the upper main sequence. Some intermediate-mass stars near the main sequence in the HR diagram imply an age for the cluster of about 10 Myr. When compared with the Scalo (The stellar initial mass function. ASP conference series, vol. 24, p. 201, 1998) IMF scaled to the cluster IMF in the intermediate mass range, 2.5≤M/M ⊙≤8.0 where there is good agreement, the high mass stars have a distinctly flatter IMF, indicating an over abundance of these stars, and there is a sharp turnover in the distribution at lower masses. The radial density distribution of cluster stars in the massive and intermediate mass regimes indicate that these stars are more concentrated to the cluster core whereas the lower-mass stars show little concentration. We suggest that this is evidence supporting the formation of massive stars through accretion and/or coagulation processes in denser cluster cores at the expense of the lower mass proto-stars. © 2007 Springer Science+Business Media B.V.

School disciplinary policies and practices are essential features of life in U.S. schools. Conventional approaches to school discipline - including conduct codes and security methods, suspension, corporal punishment, and teachers' methods of managing student behaviors - rely primarily on deterrence, control, and punishment to maintain order. However, approximately 40 years of research, chiefly in education and psychology, has demonstrated that these policies and practices are often associated with and can contribute to increased disorder in schools and behavioral and academic problems among students. Furthermore, school discipline is sometimes administered prejudicially to those students who may be the most vulnerable. School social workers and all social workers working with children and youths can help schools adopt effective and nonpunitive disciplinary approaches. Key professional actions include advocacy for schoolchildren subject to unfair and overly punitive discipline; educating teachers and administrators about the potential harm associated with conventional disciplinary practices; educating school personnel about effective, nonpunitive approaches; and creating a public campaign to generate popular support for the reform of iatrogenic school disciplinary practices. © 2006 National Association of Social Workers.

Research has identified a relationship between school disciplinary actions and poor academic and psychosocial functioning of students subjected to them. The ways in which school discipline is a direct contributor to students' academic and psychosocial difficulty needs to be further established empirically. Several theories, based in existing research and theory in sociology of education and educational psychology, have been proposed to explain the school discipline - student dysfunction relationship. They generally suggest three pathways: disciplinary actions may contribute to students' psychological problems; student misbehavior may be encouraged through ineffective and unintentionally paradoxical learning experiences; and disciplinary practices may damage students' relationship with school. School social workers and others working with children who have been disciplined at school can use these research findings and theories as an assessment framework to guide their interventions.The awareness of the iatrogenic potential of school discipline and informed assessment can support a range of evidence-based alternatives to school discipline. © 2006 National Association of Social Workers.

Growth of GaN and AlGaInN nanowires using metalorganic chemical vapor deposition (MOCVD) is investigated. It is determined that surface kinetics play an important role in non-equilibrium synthesis process such as MOCVD, in contrast to near-equilibrium synthesis by hotwall furnace reactor. Examination of crystallographic properties of GaN nanowires reveals preferential growth directions which are perpendicular to the c-axis. Such a tendency is analyzed by both thermodynamic and kinetic arguments and attributed to the minimization of (side wall) surface energy. Spontaneous formation of Al(Ga)N/GaN coaxial nanowires with distinct emission at 370 nm is observed. It is identified that the interplay between surface kinetics and thermodynamics facilitates the catalytic growth of GaN core while a limited surface diffusion of Al adatoms leads to nonselective, vapor-solid growth of Al(Ga)N sheath. The knowledge of crystallographic alignment is applied to the formation of arrayed GaN nanowires in both vertical and horizontal fashions, resulting in potentially new paradigms for creating nanoscale devices. © 2006 Materials Research Society.

Research pertaining to issues on educational services for individuals with disabilities in developing countries is scarce. The purpose of this article is to two fold: first, to contribute to the already existing literature, and, secondly, and perhaps more importantly, to provide a foundation for prospective readers to better understand literature regarding educational services for students with mental retardation. This article guides the reader to understand the perspectives towards students with mental retardation, discusses the definition and causes of this condition, and discusses issues pertaining to the identification, assessment and evaluation of these students in Kenya. The core of the article contains a discussion of the various placement options available for this population along with the curriculum in operation in the various settings. Existing barriers to effectively serving this population in Kenya and in other developing countries is also discussed.