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121.
Rainfall interception by Santa Monica's municipal urban forest 总被引:4,自引:2,他引:2
Effects of urban forests on rainfall interception and runoff reduction have been conceptualized, but not well quantified. In this study rainfall interception by street and park trees in Santa Monica, California is simulated. A mass and energy balance rainfall interception model is used to simulate rainfall interception processes (e.g., gross precipitation, free throughfall, canopy drip, stemflow, and evaporation). Annual rainfall interception by the 29,299 street and park trees was 193,168 m3 (6.6 m3/tree), or 1.6% of total precipitation. The annual value of avoided stormwater treatment and flood control costs associated with reduced runoff was $110,890 ($3.60/tree). Interception rate varied with tree species and sizes. Rainfall interception ranged from 15.3% (0.8 m3/tree) for a small Jacaranda mimosifolia (3.5 cm diameter at breast height) to 66.5% (20.8 m3/tree) for a mature Tristania conferta (38.1 cm). In a 25-year storm, interception by all street and park trees was 12,139.5 m3 (0.4%), each tree yielding $0.60 (0.4 m3/tree) in avoided flood control costs. Rainfall interception varied seasonally, averaging 14.8% during a 21.7 mm winter storm and 79.5% during a 20.3 mm summer storm for a large, deciduous Platanus acerifolia tree. Effects of differences in temporal precipitation patterns, tree population traits, and pruning practices on interception in Santa Monica, Modesto, and Sacramento, California are described. 相似文献
122.
Janet F. Werker Christopher T. Fennell Kathleen M. Corcoran Christine L. Stager 《Infancy》2002,3(1):1-30
What do novice word learners know about the sound of words? Word‐learning tasks suggest that young infants (14 months old) confuse similar‐sounding words, whereas mispronunciation detection tasks suggest that slightly older infants (18–24 months old) correctly distinguish similar words. Here we explore whether the difficulty at 14 months stems from infants' novice status as word learners or whether it is inherent in the task demands of learning new words. Results from 3 experiments support a developmental explanation. In Experiment 1, infants of 20 months learned to pair 2 phonetically similar words to 2 different objects under precisely the same conditions that infants of 14 months (Experiment 2) failed. In Experiment 3, infants of 17 months showed intermediate, but still successful, performance in the task. Vocabulary size predicted word‐learning performance, but only in the younger, less experienced word learners. The implications of these results for theories of word learning and lexical representation are discussed. 相似文献
123.
L. N. Choumak 《Intercultural Education》2002,13(4):451-461
In this article, we look at several issues relating to bilingual education in Latvia, as prescribed by the Latvian Ministry of Education and Science. We examine these issues from the perspective of the past and present situation in Belarus, Russia and the former Soviet Union. It is clear, in our view, that bilingual offers both advantages, but also various drawbacks if it is not implemented in an appropriate way. This applies to both the societal and the personal (cognitive level). Movement towards the dominant languages (in this case Latvian) needs to be viewed as a gradual process. Although each generation of newcomers might start with a passive knowledge of the dominant (second) language, this changes into a fluent grasp of the second language across generations. The original native language will lose its dominance in this process. 相似文献
124.
125.
Adult members of 79 Albanian families who had fled from Kosovo to Macedonia during the immediate postwar period (June–August 1999) were interviewed. In conjunction with therapeutic intervention, the Harvard Trauma Questionnaire (HTQ) and the General Health Questionnaire (GTQ) were administered. Trauma symptoms as measured by the HTQ and psychological distress as measured by the GHQ were highly correlated. The best predictor of psychological distress was severity of the trauma experienced. Refugees with high educational attainment had fewer trauma symptoms than those with lower educational attainment. Refugees who lived with host families in towns showed fewer trauma symptoms than those who lived in camps, but they were also more highly educated. The results of hierarchical multiple regression analyses suggested that educational attainment may mediate the effect of place of residence. Educational attainment may be an indicator of resourceful and effective coping strategies that ameliorate the effects of trauma. 相似文献
126.
The authors present a new conceptual framework for assessing and treating traumatized college students. The framework, constructivist self-development theory (CSDT), blends object relations, self-psychology, and social cognition theories. It is founded upon a constructivist view of trauma in which the individual's unique history shapes his or her experience of traumatic events and defines the adaptation to trauma. Within this theory, the authors suggest approaches to setting the frame for trauma therapy, including stabilizing acute symptoms and setting appropriate expectations for treatment. CSDT provides a framework for the systematic assessment and practical treatment of three aspects of the self that are affected by trauma. These include self-capacities, or the ability to tolerate strong affect and regulate self-esteem; cognitive schemas, or beliefs and expectations about self and others in the areas of frame of reference (or identity and world view), safety, trust, esteem, intimacy, power, and independence; and intrusive trauma memories and related distressing affect. Finally, the authors provide guidelines for assessing the need for longer term treatment. 相似文献
127.
128.
We analyze the wealth ejfects of the Texaco racial discrimination lawsuit both on the shareholders of Texaco and its major
U.S. competitors. Employing a comprehensive data set which included every case docket entry and every Wall Street Journal
article on the case as an experimental stimulus, our findings suggest that the overall cost of the case to Texaco shareholders
exceeded $500 million, that Texaco's tribulations had little, if any, impact on the share prices of its major competitors,
and that Wall Street Journal coverage of the case was highly correlated with significant changes in Texaco stock prices. This
last finding provides significant support for Hite 's suppostion that newspaper editors “key ” on ex post stock price changes
in selecting the events to be covered in the next day's edition.
The authors are grateful to Kee Chung for helpful comments on earlier drafts and also acknowlege the help-ful assistance of
the staff of the law library at the Cecil C. Humphreys School of Law at The University of Memphis. 相似文献
129.
This article compares in regression models the effects of occupational status of both fathers and mothers simultaneously upon the attainment of men and women in the Irish Republic. The sample matches male respondents from the 1973/1974 Irish Mobility Study with the labour active female sibling next closest in age. Since the analysis compares working siblings and each 'matched pair' shares the same family origin characteristics, the problems attendant upon using a sample originally of men only are partially avoided. The results advance beyond previous research since, rather than separate models by gender, models include parents and children of both genders, allowing direct rather than indirect evaluation of gender-based determinants of occupational attainment. Both fathers and mothers significantly affect children's attainment, in ways that vary by the child's gender. The results highlight the salience of mothers' attainment for their children and question the 'mainstream' model of equivalent mechanisms of occupational attainment for both genders. Models of social mobility that consider men and women as special instances of a general perspective provide the most fruitful approach for further development. 相似文献
130.
Sources of drug information among adolescent students 总被引:1,自引:0,他引:1
E Mirzaee P M Kingery B E Pruitt G Heuberger R S Hurley 《Journal of drug education》1991,21(2):95-106
A sample of 1023 eighth and tenth grade students in small to medium-sized central Texas school districts was assessed to determine the amount of information they receive from ten sources about six categories of drugs. The amount of information males reported receiving about each drug category was significantly greater than what females reported, and the amount of information that eighth graders reported receiving about each drug category was significantly greater than what tenth graders reported. Television was the primary source of drug information for all categories of drugs except inhalants, for which friends and television were equally important sources. Parents and printed media (magazines or newspapers) were of secondary importance, followed by friends and teachers. Adolescents were less likely to receive drug-related information from experience, siblings, church, doctors, and police. The reliance on the mass media for drug information in smaller school districts is a pattern which has been previously observed in larger urban districts. This consistency suggests that mass media approaches to drug education are likely to be as effective in rural areas and smaller towns as they are among urban adolescents. Implications for television programming are discussed. 相似文献