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971.
Based on intergroup theory, this study examined relationships among group characteristics (racioethnicity, gender, and level), contextual organizational unit characteristics (gender and racioethnic heterogeneity, resource support for women and racioethnic minorities) and perceptions of diversity climate by faculty at a large university. Compared to white men, white women and racioethnic minorities placed greater value on employer efforts to promote diversity, and held more favorable attitudes about the qualifications of women and racioethnic minorities. The study found that group rather than contextual organizational unit characteristics were more strongly related to diversity climate. However, the organizational unit characteristic, gender heterogeneity, was significantly related to valuing diversity. The greater the ratio of women in a unit, regardless of the respondents' gender, racioethnicity or level, the more favorable diversity activities were viewed. In addition, units whose allocation of resources to racioethnic minorities were perceived as insufficient by respondents were more likely to have members who valued diversity and held favorable perceptions toward the qualifications of racioethnic minorities. Implications for organizations and future research are offered.  相似文献   
972.
Sixteen and 17 year-olds were surveyed at motor-vehicle offices in Tennessee after qualifying for their first driver's license. When the survey was conducted during October and November 1995, neither a learner's permit nor completion of a driver education course was required to obtain a license at age 16 or 17. The survey was repeated during December and January 1996–97, approximately one year after a requirement to hold a learner's permit for 90 days or complete a driver education course was implemented. Results from the 1991 drivers (ages 16 and 17) surveyed indicated Tennessee's licensing law change was associated with approximately 100 additional miles and 8 additional hours of practice driving prior to licensure for the typical 16 or 17 year-old, most often while supervised by a parent or guardian. Results are discussed in relation to the prelicense practice driving requirements of graduated licensing systems.  相似文献   
973.

Problem

Falling is a leading cause of serious injury, loss of independence, and nursing-home admission in older adults. Impaired balance control is a major contributing factor.

Methods

Results from our balance-control studies have been applied in the development of new and improved interventions and assessment tools. Initiatives to facilitate knowledge-translation of this work include setting up a new network of balance clinics, a research-user network and a research-user advisory board.

Results

Our findings support the efficacy of the developed balance-training methods, balance-enhancing footwear, neuro-prosthesis, walker design, handrail-cueing system, and handrail-design recommendations in improving specific aspects of balance control.

Impact on Knowledge Users

A new balance-assessment tool has been implemented in the first new balance clinic, a new balance-enhancing insole is available through pharmacies and other commercial outlets, and handrail design recommendations have been incorporated into 10 Canadian and American building codes. Work in progress is expected to have further impact.  相似文献   
974.
As more people visit natural areas for tourism and recreation purposes, it is becoming increasingly important to understand the value they place on these natural resources. Specifically, tourists to Florida have been increasingly interested in visiting natural areas, forests, parks, and preserves-highlighting the importance of this new and growing phenomenon. We analyze visitors' demand for nature-based recreation in the Apalachicola River region of Florida using the travel cost method. The results from a count data regression model reveal that on average visitors would pay 74.18 dollars per visit-day for nature-based recreation resulting in a total economic value of 484.56 million dollars attributable to nature-based recreation in the Apalachicola River region. Results of this study provide useful information for natural resources management in the region and a rationale to preserve Florida's unique ecosystems.  相似文献   
975.
Depth and area of rooting are important to long-term survival of plants on metal-contaminated, steep-slope soils. We evaluated shoot and root growth and metal uptake of four cool-season grasses grown on a high-Zn soil in a greenhouse. A mixture of biosolids, fly ash, and burnt lime was placed either directly over a Zn-contaminated soil or over a clean, fine-grained topsoil and then the Zn-contaminated soil; the control was the clean topsoil. The grasses were 'Reliant' hard fescue (Festuca brevipila R. Tracey), 'Oahe' intermediate wheatgrass [Elytrigia intermedia (Host) Nevski subsp. intermedia], 'Ruebens' Canada bluegrass (Poa compressa L.), and 'K-31' tall fescue (Festuca arundinacea Schreb.). Root growth in the clean soil and biosolids corresponded to the characteristic rooting ability of each species, while rooting into the Zn-contaminated soil was related to the species' tolerance to Zn. While wheatgrass and tall fescue had the strongest root growth in the surface layers (0-5 cm) of clean soil or biosolids, wheatgrass roots were at least two times more dense than those of the other grasses in the second layer (5-27 cm) of Zn-contaminated soil. When grown over Zn-contaminated soil in the second layer, hard fescue (with 422 mg/kg Zn) was the only species not to have phytotoxic levels of Zn in shoots; tall fescue had the highest Zn uptake (1553 mg/kg). Thus, the best long-term survivors in high-Zn soils should be wheatgrass, due to its ability to root deeply into Zn-contaminated soils, and hard fescue, with its ability to effectively exclude toxic Zn uptake.  相似文献   
976.
This article summarizes a research project that investigated the use, performance, cost, and evaluation of nonstructural measures to improve urban stormwater quality. A survey of urban stormwater managers from Australia, New Zealand, and the United States revealed a widespread trend of increasing use of nonstructural measures among leading stormwater management agencies, with at least 76% of 41 types of nonstructural measures being found to be increasing in use. Data gathered from the survey, an international literature review, and a multicriteria analysis highlighted four nonstructural measures of greatest potential value: mandatory town planning controls that promote the adoption of low-impact development principles and techniques; development of strategic urban stormwater management plans for a city, shire, or catchment; stormwater management measures and programs for construction/building sites; and stormwater management activities related to municipal maintenance operations such as maintenance of the stormwater drainage network and manual litter collections. Knowledge gained on the use and performance of nonstructural measures from the survey, literature review, and three trial evaluation projects was used to develop tailored monitoring and evaluation guidelines for these types of measure. These guidelines incorporate a new evaluation framework based on seven alternative styles of evaluation that range from simply monitoring whether a nonstructural measure has been fully implemented to monitoring its impact on waterway health. This research helps to build the stormwater management industry’s knowledge base concerning nonstructural measures and provides a practical tool to address common impediments associated with monitoring and evaluating the performance and cost of these measures.  相似文献   
977.
ABSTRACT: As part of the Gulf Coast Regional Aquifer System Analysis (GC RASA) study, data from 184 geophysical well logs were used to define the geohydrologic framework of the Mississippi embayment aquifer system in Mississippi for flow model simulation. Five major aquifers of Eocene and Paleocene age were defined within this aquifer system in Mississippi. A computer data storage system was established to assimilate the information obtained from the geophysical logs. Computer programs were developed to manipulate the data to construct geologic sections and structure maps. Data from the storage system will be input to a five-layer, three-dimensional, finite-difference digital computer model that is used to simulate the flow dynamics in the five major aquifers of the Mississippi embayment aquifer system.  相似文献   
978.
Evaluation of conservation education programs can: (1) provide accountability in demonstrating a program's worth, (2) offer an opportunity for receiving feedback and improving programs, (3) further our understanding of the process of program development, and (4) promote conservation education by substantiating claims about its benefits. The Planning-Process-Product systems evaluation model provides feedback needed for making decisions about the development, implementation, and outcome of a program. Planning evaluation was useful in assessing the needs, goals, opportunities, and constraints of a number of programs in Costa Rica and Belize, such as a forestry education project and a zoo outreach program. It provided a basis for making planning decisions incorporating specific objectives, such as the reforestation of a region or a change in knowledge and attitudes in program participants. Process evaluation provided a Costa Rican sustainable development program with feedback during its implementation and enabled it to modify and improve its newsletter for local farmers and its ecology classes for school children. Product evaluation assessed project accomplishments, such as the $700,000 raised by the Children's Rainforest group and the 20 miles of riparian land under conservation management as part of the Belize Community Baboon Sanctuary project. Outcomes are compared with the programs original monetary or land management objectives to determine the success of the programs and to provide feedback for improvement.  相似文献   
979.
The potential impacts of land use on large woody debris (LWD) were examined in Sourdough Creek Watershed, a rapidly growing area encompassing Bozeman, Montana, USA. We identified six land classes within a 250 m buffer extending on either side of Sourdough Creek and assessed aquatic habitat and geomorphologic variables within each class. All LWD pieces were counted, and we examined 14 other variables, including undercut bank, sinuosity, and substrate composition. LWD numbers were generally low and ranged from 0 to 8.2 pieces per 50 m of stream. Linear regression showed that LWD increased with distance from headwaters, riparian forest width, and sinuosity in four of the six land classes. Statistically significant differences between land classes for many aquatic habitat and geomorphologic variables indicated the impacts of different land uses on stream structure. We also found that practices such as active wood removal played a key role in LWD abundance. This finding suggests that managers should prioritize public education and outreach concerning the importance of in-stream wood, especially in mixed-use watersheds where wood is removed for either aesthetic reasons or to prevent stream flooding.  相似文献   
980.
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