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981.
How do people think about the physical setting in the world around them? Part of the answer to this question may be in terms of the behaviors that occur there. To explore people's knowledge of behavior—place associations, twenty places (shown via color photographs) were assessed in five ways: (a) ratings of the place's suitability for each of eleven behaviors, (b) ratings of the expected frequency of occurrence of the eleven behaviors, (c) free listings of reasons for going to each place, (d) free listings of activities-while-there and (e) free listings of activities associated with the place. Results showed that people can distinguish places on the basis of behaviors, that the behavioral component of place meaning is composed of distinct aspects, and that knowledge of behavior is related to a global, overall representation of a place.  相似文献   
982.
Trends in the UK consumption of 12 metallic and 19 non-metallic minerals are examined for the period 1945–1980. Comparisons are drawn between these trends and developments in per capita GDP, total world consumption and UK mineral processing capacity. Although the consumption of most minerals has shown a tendency to stagnate or decline in recent years, taking the post-war period as a whole the consumption of non-metallics has displayed a faster and more sustained growth than that of metallics; thus their share of the total value of minerals consumed in the UK has increased significantly.  相似文献   
983.
984.
Summary Lake Pontchartrain is part of a brackish coastal estuarine system which serves as an important economic and recreational resource for the New Orleans region. Seafood extraction, shell dredging and leisure time activities are the major uses occurring on Lake Pontchartrain. In the past several decades, man has severely altered this system through urbanization, industrial activity, levée construction and subsequent destruction of wetlands surrounding the lake. There is a growing awareness of the environmental crisis facing Lake Pontchartrain, advanced by recent fish kills, detection of toxic chemicals, curtailment of recreational opportunities and the report of dead zones in the lake. This study summarizes a series of international environmental management techniques and examines the utilization of a regional structure for water resources management in the Lake Pontchartrain Basin.Dr. Fritz Wagner is Director and Professor of the School of Urban and Regional Studies at the University of New Orleans and David Hart was a Research Assistant in the same school, and is now employed in a local engineering and planning company.  相似文献   
985.
Book reviews     
The Garden City Utopia

Robert Beevers. The Macmillan Press, 1988. £27.50. 206 pages.

Cost‐Benefit Analysis in Urban and Regional Planning

J. A. Schofield. Allen and Unwin, London, 1987. 249 pages. £30 hardback.

The Milton Park Affair — Canada's largest citizen‐developer confrontation

Claire Helman. Véhicule Press, Montréal, 1987. $12.95.

Regenerating the Inner City, Glasgow's Experience

Edited by David Donnison and Alan Middleton. Routledge & Kegan Paul Ltd., London, 1987. £12.95.

Community Architecture

Nick Wates and Charles Knevitt. Penguin Books, London, 1987. £4.95.  相似文献   

986.
Bark included within the trunk of a 200-year-old Japanese cedar tree harvested in Yakushima Island, Japan, a World Natural Heritage Site located 150 km south of mainland Japan and 800 km east of Shanghai, China, was analysed for trace metals by ICP-MS providing a chronology of atmospheric pollution. The concentration of V, As and Pb in decadal sections of the bark pocket increased 30 to 50 fold from 1900-09 to 1960-69, indicating increased atmospheric deposition of these metals. The trend coincided with the establishment and expansion of heavy industries in Kyushu, Japan, resulting in locally high levels of air pollution. V, As and Pb subsequently declined, reflecting lower industrial emissions following air pollution control legislation from the late 1960's and decline in heavy industries. Ni, Cu and Zn showed a relatively small, 7 to 10 fold increase over time. Lead isotope ratios in the bark pockets shifted from about 0.84 to 0.86 for 207Pb/206Pb and from 2.04 to 2.10 for 208Pb/206Pb, showing that the origin of atmospheric lead changed over time from coal to more diverse sources.  相似文献   
987.
Samples collected from rural and urban streams in the City of Denton, Texas, USA were analyzed for the organophosphorus pesticides diazinon and chlorpyrifos during the years preceding and following a United States Environmental Protection Agency ban on many chlorpyrifos uses. A network of 70 monitoring stations, based mainly on topography and hydrological considerations, were established within the three main watersheds of Denton. Monitoring stations were sampled monthly from March through August during periods of normal flow (baseflow), resulting in a total of 308 samples and 311 samples collected during 2001 and 2002, respectively. Pesticide concentrations were determined using commercially available enzyme-linked immunosorbent assays (ELISA) specific for each pesticide. Results from this temporally and spatially dense monitoring effort were used to illustrate the impacts of a ban on most chlorpyrifos sales that was imposed in December 2001. The total number of samples exhibiting concentrations above method lower limits of detection (LLD) decreased between 2001 and 2002 for both chlorpyrifos and diazinon. The total number of sites exhibiting at least one sample with concentrations above the LLD for chlorpyrifos, however, significantly decreased (Fisher's exact test, p<0.0001, n=70) when comparing 2001 (before the ban) with 2002 (after the ban). Similar analyses indicated no significant difference (Fisher's exact test, p=0.50, n=70) in the number of sites exhibiting detectable diazinon concentration between 2001 and 2002. Our results indicate that the cessation of retail chlorpyrifos sales at the end of 2001 resulted in a highly significant decrease in the surface water occurrences of this pesticide during 2002.  相似文献   
988.
This is the second update of research on graduated driver licensing (GDL) and teenage drivers. It briefly summarizes research in progress and research published since the January 2004 update (Hedlund, J. & Compton, R. [2004]. Graduated driver licensing research in 2003 and beyond. Journal of Safety Research 35(1), 5-11). Research has been very active, especially on teenage driver risk factors, GDL program evaluations, the role of parents in managing and training their teenage drivers, and driver education. Results have strengthened the case for GDL, for nighttime and passenger restrictions, and for extended supervised driving practice.  相似文献   
989.
INTRODUCTION: The purpose of this study was to examine the impact of a nationwide response to emerging airbag-related deaths among children. This response, implemented in 1996, focused on moving children to a rear seat and increasing proper restraint usage. METHOD: Fatality trends from 1992 through 1996 and from 1996 through 2003 were examined for younger children (ages 0-3) and for older children (ages 4-12). RESULTS: Prior to 1997, a steady reduction in unrestrained deaths (among younger children) was offset by increases in restrained deaths (among younger and older children), increases in rear-seat deaths (among younger children), and increases in front-seat deaths (among older children). After 1996, there were significant decreases in fatalities in both age groups, with larger and more immediate reductions among the younger children. The largest reductions were immediately after 1996, when younger-child deaths declined by 16%, and after 1999, when deaths among both age groups declined by about 16%. CONCLUSIONS: The immediate reduction in front-seat deaths among younger children, particularly infants, appears to have been closely associated with the nationwide public information efforts implemented in 1996. Later reductions in front-seat and unrestrained deaths, among both younger and older children, were likely associated with the combination of legislative, enforcement, and public information programs, which increased after 1999. IMPACT ON INDUSTRY: The findings suggest that a large expenditure of resources by public and private-sector organizations after 1996 resulted in the prevention of hundreds of deaths among young children. In addition, the results provide insights with regard to the categories of deaths most affected by such programs and issues that deserve additional attention.  相似文献   
990.
Corn distillers’ dry grain, corncob powder, hardwood powder, and sugar beet pulp were separately anionized by oxidation with sodium hypochlorite in aqueous solution. Solid reaction products instantly precipitated upon admixing each of the above-oxidized materials with soy protein isolate. Infrared spectra and differential scanning calorimetry supported the hypothesis that soy protein isolate complexed with all of the above-oxidized polysaccharides. Reaction products with either oxidized corn distillers’ dry grain or oxidized sugar beet pulp provided hard, brittle pellets with tensile strengths as high as 9.5 MPa, suggesting that these materials could be viable as biodegradable plastics.  相似文献   
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