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131.
Noise emanating from human activity has become a common addition to natural soundscapes and has the potential to harm wildlife and erode human enjoyment of nature. In particular, motor vehicles traveling along roads and trails produce high levels of both chronic and intermittent noise, eliciting varied responses from a wide range of animal species. Anthropogenic noise is especially conspicuous in natural areas where ambient background sound levels are low. In this article, we present an acoustic method to detect and analyze motor vehicle noise. Our approach uses inexpensive consumer products to record sound, sound analysis software to automatically detect sound events within continuous recordings and measure their acoustic properties, and statistical classification methods to categorize sound events. We describe an application of this approach to detect motor vehicle noise on paved, gravel, and natural-surface roads, and off-road vehicle trails in 36 sites distributed throughout a national forest in the Sierra Nevada, CA, USA. These low-cost, unobtrusive methods can be used by scientists and managers to detect anthropogenic noise events for many potential applications, including ecological research, transportation and recreation planning, and natural resource management.  相似文献   
132.
A model of resource evaluation incorporating reversibility of actions and substitutability for resource services is presented, along with associated decision criteria. The model extends and generalizes the Krutilla—Fisher procedure for evaluating unique resources. The more general technique is used to assess the official analysis of the Tellico Dam project in eastern Tennessee. In terms of measured values, the preservation option is shown to be superior to development only under extreme assumptions. The existence of substantial unmeasured preservation values in the Tellico case strengthens the environmentalist position, however, particularly since net benefits of development are apparently negative.  相似文献   
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INTRODUCTION: Many injury prevention interventions require changes in human behavior to reduce self-risk or risk to others. Promising injury prevention interventions may be discarded if they lack power to create a significant difference in outcomes when judging their ability to "move a person from nonaction or negative action to positive action (safety)." The transtheoretical model of change (TMC) allows greater sensitivity in detecting along the change process where an intervention may be effective. The stages of change consist of precontemplation, contemplation, preparation, action, maintenance, and termination. Change is not viewed as an "all or none phenomenon." METHOD: Use of the TMC was examined using a quasiexperimental, cross-over design involving high school agriculture students enrolled in 21 schools in Kentucky (n=9), Iowa (n=7), and Mississippi (n=5). A series of physical and narrative simulations (safety training exercises) were developed with a focus on preventing amputation, spinal cord injury, hypersensitivity pneumonitis, and noise-induced hearing loss. Contemplation and action, as part of the TMC, were measured using a 10-item, Likert-type, stages of change (SOC) instrument comprised of two subscales (reliability coefficients were.88 and.81, respectively). The final sample consisted of 790 students (373 treatment and 417 control). RESULTS: There was a significant group effect for both contemplation, F(1,732)=197.4; p<.0001, and action, F(1,730)=106.1; p<.0001. A convenience sample of 29 of the participating students was selected for follow-up farm visits 1 year postparticipation. Of these students, 25 (86%) had made safety behavior changes in their farm work. IMPACT ON INDUSTRY: The use of the TMC model can provide researchers with greater precision in examining intervention effectiveness in promoting change.  相似文献   
136.
Objective: Although advanced restraint systems, such as seat belt pretensioners and load limiters, can provide improved occupant protection in crashes, such technologies are currently not utilized in military vehicles. The design and use of military vehicles presents unique challenges to occupant safety—including differences in compartment geometry and occupant clothing and gear—that make direct application of optimal civilian restraint systems to military vehicles inappropriate. For military vehicle environments, finite element (FE) modeling can be used to assess various configurations of restraint systems and determine the optimal configuration that minimizes injury risk to the occupant. The models must, however, be validated against physical tests before implementation. The objective of this study was therefore to provide the data necessary for FE model validation by conducting sled tests using anthropomorphic test devices (ATDs). A secondary objective of this test series was to examine the influence of occupant body size (5th percentile female, 50th percentile male, and 95th percentile male), military gear (helmet/vest/tactical assault panels), seat belt type (3-point and 5-point), and advanced seat belt technologies (pretensioner and load limiter) on occupant kinematics and injury risk in frontal crashes.

Methods: In total, 20 frontal sled tests were conducted using a custom sled buck that was reconfigurable to represent both the driver and passenger compartments of a light tactical military vehicle. Tests were performed at a delta-V of 30 mph and a peak acceleration of 25 g. The sled tests used the Hybrid III 5th percentile female, 50th percentile male, and 95th percentile male ATDs outfitted with standard combat boots and advanced combat helmets. In some tests, the ATDs were outfitted with additional military gear, which included an improved outer tactical vest (IOTV), IOTV and squad automatic weapon (SAW) gunner with a tactical assault panel (TAP), or IOTV and rifleman with TAP. ATD kinematics and injury outcomes were determined for each test.

Results: Maximum excursions were generally greater in the 95th percentile male compared to the 50th percentile male ATD and in ATDs wearing TAP compared to ATDs without TAP. Pretensioners and load limiters were effective in decreasing excursions and injury measures, even when the ATD was outfitted in military gear.

Conclusions: ATD injury response and kinematics are influenced by the size of the ATD, military gear, and restraint system. This study has provided important data for validating FE models of military occupants, which can be used for design optimization of military vehicle restraint systems.  相似文献   

137.
Infants, children, adolescents, and pregnant and lactating women have been described as groups with special needs. Regardless of diet chosen, these groups are at higher risk for nutritional deficiencies than adult males. Vegan diets can be safely used by these groups if foods, and in some instances supplements, are selected which provide a healthful and nutritionally adequate diet. Guidelines have been developed for those choosing to follow vegan diets. In many instances vegan diets offer health benefits. Studies of vegans are limited by factors such as heterogeneity of diets, the size and extent of this type of study, and difficulty in subject identification. There is a scarcity of studies of newer vegetarians who are often more mainstream than the vegetarians of the 1960s and 1970s. In some instances this has led to assumptions about today's vegans which are based on out-dated information. Thorough scientific studies of today's vegetarians, especially of those in groups with special needs, are needed.  相似文献   
138.
As human influences fragment native communities and ecosystems, remaining land must be better managed to conserve many elements of biodiversity. Much of this land is privately held, yet traditional private land-use management practices often further diminish biodiversity by promoting favored or edge-adapted species. Today, private land stewards are increasingly aware of and concerned about biodiversity, but little guidance exists for them to make land-use decisions incorporating principles and knowledge from conservation biology. Consequently, most management strategies are highly subjective. This article addresses that problem by introducing current conservation wisdom to management and use of private lands. The result is a model program for developing land management plans, with the goal of maintaining viable populations and natural distributions of native species and communities from a landscape perspective. The program establishes a protocol for classifying sites according to the importance of their species, communities, and other elements to global and regional biodiversity. These site classifications are based on the management objectives necessary to maintain important elements. Once managers classify a site, the program provides management standards, general stewardship principles, examples of land management strategies, and basic monitoring and evaluation procedures.  相似文献   
139.
A computer model called the Ozone Risk Assessment Model (ORAM) was developed to evaluate the health effects caused by ground-level ozone (O3) exposure. ORAM was coupled with the U.S. Environmental Protection Agency's (EPA) Third-Generation Community Multiscale Air Quality model (Models-3/CMAQ), the state-of-the-art air quality model that predicts O3 concentration and allows the examination of various scenarios in which emission rates of O3 precursors (basically, oxides of nitrogen [NOx] and volatile organic compounds) are varied. The principal analyses in ORAM are exposure model performance evaluation, health-effects calculations (expected number of respiratory hospital admissions), economic valuation, and sensitivity and uncertainty analysis through a Monte Carlo simulation. As a demonstration of the system, ORAM was applied to the eastern Tennessee region, and the entire O3 season was simulated for a base case (typical emissions) and three different emission scenarios. The results indicated that a synergism occurs when reductions in NOx emissions from mobile and point sources were applied simultaneously. A 12.9% reduction in asthma hospital admissions is expected when both mobile and point source NOx emissions are reduced (50 and 70%, respectively) versus a 5.8% reduction caused by mobile source and a 3.5% reduction caused by point sources when these emission sources are reduced individually.  相似文献   
140.
Octocorals are diverse and abundant on many marine hard substrates, and, within this group, members of the family Plexauridae are an important component of tropical reef assemblages, especially in the Caribbean. To understand historical relationships within this large and diverse assemblage, and to test the monophyly of the family and some of its genera, DNA sequences of two mitochondrial loci (msh1 and ND2, ~1,185 bp) were analyzed from 46 species in 21 genera from deep and shallow waters in the tropical western Atlantic and in the tropical western and eastern Pacific (plus 9 taxa in the closely related Gorgoniidae and 1 species of the more distantly related Alcyoniidae). Five strongly supported clades were recovered. Three large clades correspond roughly to the Plexauridae, Paramuriceidae, and Gorgoniidae, and two smaller clades were comprised of taxa previously assigned to several families. Astrogorgia sp. did not group with any of the clades. The mutual relationships among the five clades remain unclear. Several genera previously regarded as unrelated appear to be grouped among the three families; e.g. Hypnogorgia sp. (Paramuriceidae) falls within a clade consisting of both Pacific and Atlantic Muricea spp. (Plexauridae), while Swiftia sp., Scleracis sp., and an Atlantic Thesea sp. (all Paramuriceidae) group with the gorgoniids. In several instances, genera containing Atlantic and Pacific species were recovered as monophyletic (Muricea spp., Bebryce spp.). However, in at least three cases (Echinomuricea spp., Thesea spp., Villogorgia spp.), placement of Atlantic and Pacific species in the same genus may reflect convergence of sclerite morphology. The results indicate a strong need for reexamination of octocoral taxonomy using a combination of molecular, morphological, and chemical evidence.Electronic Supplementary Material Supplementary material is available in the online version of this article at http://dx.doi.org/10.1007/s00227-005-1592-y.Communicated by J.P. Grassle, New Brunswick  相似文献   
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