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921.
922.
James C. McDavid Annette E. Mueller 《Canadian public administration. Administration publique du Canada》2008,51(4):589-615
Abstract: The primary purpose of this article is to investigate the factors that predict the efficiency of residential recycling collection services in Canadian local governments. The findings are based on a survey of 128 residential recycling producers from all regions of Canada. One of the most significant findings is the lack of a relationship between private‐sector companies collecting recyclables and the overall efficiency of collection operations. The dominance of the private‐sector collection of recyclables (over seventy‐seven per cent of all producers were contracted companies) does not translate into greater efficiencies. The most important variables in the model are amenable to local control. They include tonnes collected per vehicle per year, requiring full bins, inclusion of composting operations in the overall recycling program, the number of different kinds of materials recycled, participation rate, and reliance on side‐loading collection vehicles. Among the direct predictors of unit costs, the key underlying factor is the productivity of residential recycling operations. Because recyclables are marketed, handling them takes time, reduces the weights that collection vehicles can carry, and generally reduces productivity. Even diligent efforts to improve productivity will not bring recycling costs down to the levels for residential solid‐waste collection. Sommaire: L'objectif principal du présent article est d'examiner les facteurs qui prévoient l'efficacité des services de collecte de produits recyclables résidentiels dans les municipalités canadiennes. Les résultats reposent sur un sondage réalisé auprès de 128 producteurs de collecte de produits recyclables résidentiels opérant dans toutes les régions du Canada. L'un des résultats les plus notoires est le manque de relations entre les sociétés du secteur privé qui récupèrent les produits recyclables et l'efficacité d'ensemble des opérations de collecte. La prédominance de la collecte de produits recyclables par le secteur privé (plus de soixante‐dix‐sept pour cent de tous les producteurs étaient des sociétés contractuelles) ne se traduit pas par une plus grande efficacité. Les variables les plus importantes du modèle peuvent faire l'objet d'un contrôle local. Elles comprennent les tonnes récupérées par véhicule par an, l'exigence de poubelles pleines, l'inclusion d'opérations de compostage au programme général de recyclage, le nombre de différentes sortes de matériaux recyclés, le taux de participation, et le recours à des camions de collecte à chargement latéral. Parmi les variables explicatives directes des coûts unitaires, le principal facteur sous‐jacent est la productivité des opérations de recyclage résidentiel. Comme les produits recyclables sont commercialisés, leur manutention prend du temps, réduit le poids que les camions de collecte peuvent transporter, et réduit d'une manière générale la productivité. Même des efforts diligents pour améliorer la productivité ne feront pas baisser les coûts du recyclage aux niveaux de ceux de la collecte des déchets solides résidentiels. 相似文献
923.
Petra M. van de Looij-Jansen Judith E. J. Goldschmeding Erik Jan de Wilde 《Journal of youth and adolescence》2006,35(4):652-658
Self-report questionnaires are frequently used in youth research, but doubt remains whether total anonymity affects the results. This study compared the responses of 704 mainly 16–17-year-old adolescents to self-report measures of various health indicators in 2 groups: anonymous and confidential collection. For most health indicators no significant differences were found. Perceived health, use of alcohol, and aggressive behavior (for boys) were reported significantly less frequently in the confidential group (small effect size). It appeared that pupils with high scores on social desirability do not respond differently at most health indicators in the 2 conditions. For most health characteristics, epidemiologically useful outcomes may be derived from confidential self-report measures, which are also valuable for detecting individual at-risk children. Similar studies in lower grades and other types of education should confirm the results.Youth Department, Municipal Health Service Rotterdam area. Main research interests are emotional and behavioral problems of adolescents, youth health care, monitoring.Youth Department, Municipal Health Service Rotterdam area. Main research interests are emotional and behavioral problems of adolescents, youth health care, monitoring.Research Department, Municipal Health Service Rotterdam area. Major research interests include emotional and behavioral problems of adolescents, suicidal behavior, youth health care, monitoring. 相似文献
924.
Christopher A. Thurber Marge M. Scanlin Leslie Scheuler Karla A. Henderson 《Journal of youth and adolescence》2007,36(3):241-254
Three thousand, three hundred and ninety-five families, whose child attended one of 80 different day or resident summer camps
for at least one week, completed customized questionnaires that measured growth from precamp to postcamp in four domains:
Positive Identity, Social Skills, Physical & Thinking Skills, and Positive Values & Spirituality. Parents, children, and camp
staff reported significant positive change in these four domains; more than would be expected by maturation alone. Most gains
were maintained or showed additional growth six months later. Few of the camp's structural elements correlated with growth,
nor did striking gender, age, or ethnicity differences emerge. The study highlights the particular strengths of camp as an
educational institution and social movement and suggests that different variations of summer camp can provide potent developmental
experiences.
Christopher A. Thurber is full-time faculty at Phillips Exeter Academy in Exeter, New
Hampshire. He received his PhD in clinical psychology from the University of California, Los
Angeles, in 1997. His major research interests include homesickness, youth camping, and
developmental psychopathology.
Margery M. Scanlin is the Executive Officer for Research at the American Camp Association in
Martinsville, Indiana. She received her EdD from Temple University in Philadelphia, PA, in
1982. Her major research interests include youth development outcomes, program improvement
in youth organizations, and organizational aspects of effective camps.
Leslie Scheuler Whitaker is a Senior Associate with Philliber Research Associates in St. Louis,
Missouri. She received her PhD in social science research from Washington University in St.
Louis in 2000. Her primary research areas include youth development, arts education, and
program evaluation.
Karla A. Henderson is a professor in the Department of Parks, Recreation, and Tourism at North
Carolina State University. She received her PhD in education from the University of Minnesota
in 1979 and is currently a member of the American Camp Association Board of Directors. Her
research interests include leisure behavior theory, camping and outdoor education, and gender
and diversity issues. 相似文献
925.
Unmet mental health need is a significant problem for adolescents. Although stigma is identified as a major barrier to the
use of mental health services among youth, there is limited research on this topic. In-depth interviews (n=57) among a sample of 8th grade students in a suburban, mid-Atlantic community portray adolescent mental health attitudes
and how these views are shaped. Satisfactory personal experiences with mental health services as well as accurate mental health
knowledge contribute to positive mental health attitudes among teens. The anticipation of negative responses towards mental
health care-seeking from family members, peers, and school staff are key factors in teens’ comfort and willingness to address
mental health concerns. The research provides critical information on the factors that contribute to the development of stigma
and emphasizes the need to address stigma in youth mental health education, programs, and treatment plans.
Authors are affiliated with the Johns Hopkins Bloomberg School of Public Health, Department of Population and Family Health
Sciences. Dr. Chandra has a background in adolescent health, and is particularly interested in improving the accessibility
and appropriateness of youth mental health services and involving young people in the translation of research into practice.
Dr. Minkovitz is interested in improving preventive service delivery, enhancing quality of care, and understanding maternal
factors that influence children’s receipt of health care 相似文献
926.
David B. Estell Thomas W. Farmer Matthew J. Irvin Jana H. Thompson Bryan C. Hutchins Erin M. McDonough 《Journal of youth and adolescence》2007,36(4):477-487
The transition to high school has been identified as a potentially difficult time in adolescents’ lives. Reductions in both
academic and social functioning often accompany this transition. While these effects have been documented in urban youth,
the move to high school has not been extensively studied in rural minority youth. Toward that end, the academic grades and
substance use in ninth grade of 447 (184 male and 263 female) African-American adolescents from two rural counties in a state
in the deep South were examined in relation to configurations of adaptation from sixth through eighth grade. Results indicate
that individual with consistently positive patterns across middle school had higher grades and lower rates of substance use
compared to individuals with persistent difficulties or those that transitioned to problem behavior. Many individuals who
improved in their patterns of adaptation had relatively high grades, but also rather high rates of substance use in the ninth
grade.
David B. Estell is an assistant professor of educational psychology at Indiana University Bloomington. He received his PhD
in Developmental Psychology from the University of North Carolina at Chapel Hill. His major research interests include peer
relations and the development of aggression.
Thomas W. Farmer is an associate professor of education at Pennsylvania State University and director of the National Research
Center on Rural Education Support. He received his PhD in Special Education from University of North Carolina at Chapel Hill.
His major research interests include peer relations and the development of aggression in students with and without special
needs.
Matthew J. Irvin is a research scientist at the Center for Developmental Science at the University of North Carolina at Chapel
Hill. He received his PhD in Educational Psychology from the University of North Carolina at Chapel Hill. His major research
interests include resilience and student engagement.
Jana H. Thompson is a research associate at the Center for Developmental Science at the University of North Carolina at Chapel
Hill. Her research interests include peer social relations and developmental transitions into early adolescence.
Bryan C. Hutchins is a research assistant at the Center for Developmental Science at the University of North Carolina at Chapel
Hill. He is also a graduate student in the Educational Psychology, Measurement, and Evaluation Program at UNC. His research
interests include child and adolescent social development and school based emotional and behavioral interventions and prevention
programs.
Erin M. McDonough is currently a doctoral candidate in School Psychology at the University of North Carolina at Chapel Hill.
She received her Bachelor of Arts degree in Psychology from Emory University. As a research assistant at the Center for Developmental
Science, she has been able to explore her interests in student achievement as well as rural education. Another major research
interest of hers is school-based mental health. 相似文献
927.
Gender Differences in the Educational Expectations of Urban,Low-Income African American Youth: The Role of Parents and the School 总被引:1,自引:1,他引:1
This study examined how youths’ gender is related to the educational expectations of urban, low-income African American youth,
their parents, and their teachers. As predicted, African American boys (ages 9–16) reported lower expectations for future
educational attainment than did their female counterparts. Parents and teachers also reported lower expectations for African
American boys (ages 6–16) than for girls. These findings held even when controlling for academic achievement. Contrary to
predictions, the magnitude of the difference in expectations for males vs. females did not increase as a function of youths’
age. In keeping with our hypotheses, parental expectations fully mediated the relation between youths’ gender and youths’
expectations. Finally, certain school-based factors (i.e., positive teacher expectations and positive youth perceptions of
the school environment) appeared to protect youths’ expectations from the deleterious impact of low parental expectations.
相似文献
Dana WoodEmail: |
928.
929.
930.