System size dependence of freeze-out properties at RHIC

The STAR experiment at RHIC has measured identified pi(+/-), K(+/-) and p(pbar) spectra and ratios from sqrt(s_NN) = 62.4 and 200 GeV Cu+Cu collisions. The new Cu+Cu results are studied with hydro-motivated blast-wave and statistical model frameworks in order to characterize the freeze-out properties of this system. Along with measurements from Au+Au and p+p collisions, the obtained freeze-out parameters are discussed as a function of collision energy, system size, centrality and inferred energy density. This multi-dimensional systematic study reveals the importance of the collision geometry and furthers our understanding of the QCD phases.Comment: 6 pages, 6 figures, poster proceedings for the Quark Matter 2006 Conference, Shanghai, China, 14th-20th Novermber 2006, submitted to the International Journal of Modern Physics

Radiochemical studies on free radicals

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How social science helped end the death penalty in Colorado

Last month, Colorado became the latest US state to abolish the death penalty. Hollis A. Whitson writes on how the move has been the culmination of years of work from abolitionists and social scientists who built a convincing base of evidence on the racial and geographic disparities of the death penalty in Colorado

Control valve: Hot gas fast response

The design of a warm gas control valve is reviewed outlining the problems posed by the requirement for extremely fast response combined with a severe environment and a hot, dirty, and corrosive operating fluid

Social Work in Schools in New Zealand: Indigenous Social Work Practice

Social workers have found a new professional presence in New Zealand schools since 2001 following a pilot program in a small cluster of schools in 1999. Schools that are in low socio-economic communities have been selected to engage the services of in-school social workers. These schools have a high proportion of Maori and Pacific Island children and families in a country where Maori make up 15% of the population and Pacific Island families now make up 7% of the population. Maori social service providers are keen to employ Maori social workers so that there is congruence with their clients. These workers must then manage the multiple relationships they encounter in small rural communities in New Zealand. School social work enables helping professionals to work in health and counselling teams with families, contributing to positive Maori development and empowering families

Public Perception and Influential Sources Toward Child Welfare Services

The purpose of this study is to answer the following questions: “What is the current public attitude toward public child welfare services and what sources of information have been used to formulate these attitudes?” In answering these questions, child welfare agencies would have a better understanding of what populations to promote public outreach, education, or further community involvement based on demographics and/or which venues to implement such outreach. This study provides information on previous studies where researchers have looked at the general role of social work and used the gathered information to assess public sentiment. In past research there has been discrepancy in the outcomes of this data. Past research has also incorporated news media and the portrayal of child welfare social workers, but has not attempted to measure the impacts of media and the public’s perception of the profession. With recent societal events, it has become more evident that public perception can be a driving force in policy change. The intent of this study is to identify individual demographic information (e.g., race/ethnicity, income level, household size, prior child welfare system involvement, etc.) that would show a significant relationship with a developed scale to measure participants’ attitude or sentiment toward child welfare social work. To obtain participants, a link to the developed survey was posted to multiple social media pages where the primary subject included the Victor Valley region of San Bernardino County, California. Participants were also asked to repost the link to the survey to their social media pages in order to increase participant numbers. For this project, 183 participants completed the survey to completion. Due to the level of measurement of the variables, multiple data analysis techniques were used in order to identify relationships between the independent demographic variables and the score on the sentiment scale. These techniques include t-tests, ANOVA, and correlation. Of the variables measured for statistical significance, only the participants past levels of child welfare services involvement showed significance. This was especially true for participants who had experiences both as a minor and as a parent. Income level, news sources, and other demographic identifiers did not show statistically significant differences in sentiment toward child welfare social work. With the information from this study, child welfare agencies might implement further outreach to the identified populations in order to provide further support. This information can also identify which specific factors contribute to the negative perceptions through qualitative analysis

The Oxidation Of Dilute Alloys Of Magnesium In Aluminium

The oxide layers developed during the oxidation of aluminum alloys containing 500 and 1000 PPM of magnesium at 850K were examined with the aid of electron spectroscopy for chemical analysis. The magnesium content of the oxide layers was relatively high because of the preferential depletion of the magnesium atoms from the base alloys. Near the outer surfaces of the oxide layers, spinel (MgAl2O4) was the predominant magnesium-bearing compound. At depth, MgO was more dominant. The preferential depletion of magnesium from the alloys injected vacancies into the material. This led to the formation of defect clusters. The presence of these defect clusters explains the experimental observations reported earlier by other researchers

Density Changes during Isothermal Annealing of a Quenched Pb–7.45 At% Sn Alloy

The increase in density of a Pb–7.45 at% Sn alloy annealed at 150, 165, 180, and 195 °C and quenched at 20, 21.5, 23, 25, and 30 °C is measured isothermally. This increase in density accompanies the formation of the Sn‐rich phase precipitating as a function of time at the quenching temperature. The quenching is rapid enough to retain some vacancies at equilibrium at the annealing temperature. These vacancies accelerate the early stages of precipitation. The change in density versus time obeys the kinetic law allowing the determination of the reaction rate constant for several annealing and quenching conditions. Copyright © 1994 WILEY‐VCH Verlag GmbH & Co. KGa