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271.
Males discriminate between the single most important individual component of the sex pheromone of the female cabbage looper, Trichoplusia ni (Hübner), (Z)-7-dodecenyl acetate (Z7-12:Ac), and a mixture containing Z7-12:Ac and the other five putative components. The manifestation of discrimination is not an enhancement of captures by the mixture, rather, it is a reduction of captures in a paired trap baited with Z7-12:Ac by itself. Previous experiments showed that either or both of (Z)-7-tetradecenyl acetate (Z7-14:Ac) and (Z)-9-tetradecenyl acetate (Z9-14:Ac) were responsible for this discrimination. This report provides evidence that Z7-14:Ac is more active than Z9-14:Ac, which appears to have no demonstrable effect on behavior. The results are discussed with reference to the behavior that is effected by the above three components, the composition of the native sex pheromone, and whether or not Z7-12:Ac might be a supernormal releaser of behavior.  相似文献   
272.
The Abbotsford-Sumas Aquifer is a shallow, predominantly unconfined aquifer that spans regions in southwestern British Columbia, Canada and northwestern Washington, USA. The aquifer is prone to nitrate contamination because of extensive regional agricultural practices. A 22-month ground water nitrate assessment was performed in a 10-km2 study area adjacent to the international boundary in northwestern Washington to examine nitrate concentrations and nitrogen isotope ratios to characterize local source contributions from up-gradient sources in Canada. Nitrate concentrations in excess of 10 mg nitrate as nitrogen per liter (mg N L(-1)) were observed in ground water from most of the 26 domestic wells sampled in the study area, and in a creek that dissects the study area. The nitrate distribution was characteristic of nonpoint agricultural sources and consistent with the historical documentation of agriculturally related nitrate contamination in many parts of the aquifer. Hydrogeologic information, nitrogen isotope values, and statistical analyses indicated a nitrate concentration stratification in the study area. The highest concentrations (> 20 mg N L(-1)) occurred in shallow regions of the aquifer and were linked to local agricultural practices in northwestern Washington. Nitrate concentrations in excess of 10 mg N L(-1) deeper in the aquifer (> 10 m) were related to agricultural sources in Canada. The identification of two possible sources of ground water nitrate in northwestern Washington adds to the difficulty in assessing and implementing local nutrient management plans for protecting drinking water in the region.  相似文献   
273.
ABSTRACT The movement of fallout 137Cs carried by soil particles was studied as an indicator of erosion and sedimentation in the Allerton watersheds and 4-H Memorial Lake located near Monticello, Illinois. Sediment deposition was greater in the waterway draining from watershed IB than in the waterway from watershed IA. At the average rate of 2.3 cm/yr of sediment deposition in the lake (from 1954 to 1979), there will be a loss of over 2 meters of water depth in the next century. However, there appears to be a decreasing rate of sediment deposition in the 4-H Memorial Lake as a result of improved conservation practices on the watersheds and the increased effectiveness of vegetated waterways and buffers for retaining sediment.  相似文献   
274.

Introduction

Information from hospital trauma registries is increasingly being used to support injury surveillance efforts. This research examines the potential of using trauma registry data for road traffic injury surveillance for different types of road users in terms of both the information collected and how representative trauma data are compared to two population-based road traffic injury data collections.

Methods

The three data collections were assessed against recommended variables to be collected for injury surveillance purposes and the representativeness of the distribution of road traffic-related injury data from the trauma registry was compared to hospital admission and road traffic authority data collections.

Results

Data from the trauma registry was largely not representative of the distribution of age groups or activities compared to the two population-based collections, but was representative for gender for some road user groups to at least one population-based data collection.

Conclusions

Trauma data could be used to supplement information from population-based data collections to inform road safety efforts.

Impact on Industry

Road safety policy makers should be aware of the potential and the limitations of using trauma registry data for road traffic injury surveillance.  相似文献   
275.
Abstract

This paper presents an evaluation framework that aims to improve the outcomes of triple bottom line (TBL) reporting. Currently, most assessments of TBL reporting focus on report content. Our view is that effective evaluation of TBL reporting should go beyond reports as the outputs of a process and focus on what is being learned through the process, the capacity- and relationship-building that might eventuate, and how this impacts on the development of sustainability. To enable more effective reflection of TBL reporting processes, we developed a set of evaluation criteria focused on the process of reporting. These criteria were identified from case studies of social, environmental and/or sustainability reporting processes documented in the literature. A large number of potential criteria were synthesised into three desired outcomes of TBL reporting and 10 prompts for discussion and reflection during evaluation. This evaluation framework should assist those dedicated to challenging assumptions that inhibit progress towards a sustainable future for society.  相似文献   
276.
Background: There is a need for routine estimates of injury recovery costs from pedestrian collisions using hospital separation records for economic evaluations.

Objective: To estimate the cost of injury recovery following pedestrian–vehicle collisions using the personal injury recover cost (PIRC) equation using key demographic and injury characteristics.

Method: An estimation of the costs of on-road pedestrian–vehicle collisions involving individuals who were injured and hospitalized in New South Wales (NSW), Australia, from 2002 to 2011 using the PIRC equation. The PIRC estimates individual injury recovery costs and does not include costs associated with property damage, vehicle repair, or rescue services. Individual recovery costs associated with severe traumatic brain injury (TBI) were estimated. The injured individual's mean, median, and total injury recovery costs are described for key demographic, injury, and crash characteristics.

Results: There were 9,781 pedestrians who were injured, costing an estimated total of $2.4 billion in personal injury recovery costs, an annual cost of $243 million. Males had a total injury recovery cost 1.7 times higher than females. The median injury recovery cost decreased with increasing age. TBI ($248,491) and spinal cord and vertebral column injuries ($264,103) had the highest median injury recovery costs for the body region of the most severe injury. TBI accounted for 22.6% of the total injury recovery costs for the most severe injury sustained. Just over one third of pedestrians sustained 4 or more injuries, with a median cost of $243,992, which was 1.6 times higher than the cost for a pedestrian who sustained a single injury ($153,682).

Conclusions: Personal injury recovery costs following pedestrian–vehicle collisions where a pedestrian is injured are substantial in NSW. The PIRC equation enables the economic cost burden of road traffic injury to be calculated using hospital separation data. The PIRC enables comprehensive personal injury recovery costs to be estimated and would aid in economic evaluations of preventive strategies in road safety.  相似文献   

277.
Mercury, a toxic metal known to have several deleterious affects on human health, has been one of the principal contaminants of concern in the Great Lakes basin. There are numerous anthropogenic sources of mercury to the Great Lakes area. Combustion of coal, smelting of non ferrous metals, and incineration of municipal and medical waste are major sources of mercury emissions in the region. In addition to North American anthropogenic emissions, global atmospheric emissions also significantly contribute to the deposition of mercury in the Great Lakes basin. Both the USA and Canada have agreed to reduce human exposure to mercury in the Great Lakes basin and have significantly curtailed mercury load to this region through individual and joint efforts. However, many important mercury sources, such as coal-fired power plants, still exist in the vicinity of the Great Lakes. More serious actions to drastically reduce mercury sources by employing alternative energy sources, restricting mercury trade and banning various mercury containing consumer products, such as dental amalgam are as essential as cleaning up the historical deposits of mercury in the basin. A strong political will and mass momentum are crucial for efficient mercury management. International cooperation is equally important. In the present paper, we have analyzed existing policies in respective jurisdictions to reduce mercury concentration in the Great Lakes environment. A brief review of the sources, occurrence in the Great Lakes, and the health effects of mercury is also included.  相似文献   
278.
Spring snowmelt is an important period of mercury (Hg) export from watersheds. Limited research has investigated the potential effects of climate variability on hydrologic and Hg fluxes during spring snowmelt. The purpose of this research was to assess the potential impacts of inter-annual climate variability on Hg mobility in forested uplands, as well as spatial variability in hillslope hydrology and Hg fluxes. We compared hydrological flows, Hg and solute mobility from three adjacent hillslopes in the S7 watershed of the Marcell Experimental Forest, Minnesota during two very different spring snowmelt periods: one following a winter (2009-2010) with severely diminished snow accumulation (snow water equivalent (SWE) = 48 mm) with an early melt, and a second (2010-2011) with significantly greater winter snow accumulation (SWE = 98 mm) with average to late melt timing. Observed inter-annual differences in total Hg (THg) and dissolved organic carbon (DOC) yields were predominantly flow-driven, as the proportion by which solute yields increased was the same as the increase in runoff. Accounting for inter-annual differences in flow, there was no significant difference in THg and DOC export between the two snowmelt periods. The spring 2010 snowmelt highlighted the important contribution of melting soil frost in the timing of a considerable portion of THg exported from the hillslope, accounting for nearly 30% of the THg mobilized. Differences in slope morphology and soil depths to the confining till layer were important in controlling the large observed spatial variability in hydrological flowpaths, transmissivity feedback responses, and Hg flux trends across the adjacent hillslopes.  相似文献   
279.
Brushland wildlife within the Lower Rio Grande Valley of south Texas were studied following applications of eleven insecticides to nearby sugarcane or cotton fields. During the study no wildlife were found dead. Mean brain acetylcholinesterase (AChE) activity of great-tailed grackles (Quiscalus mexicanus) and mourning doves (Zenaida macroura) was significantly lower than controls following application of some organophosphorous insecticides. Brain AChE activity varied significantly among chemicals, days after exposure and application rates. Mean brain AChE activity of white-winged doves (Zenaida asiatica) and three small mammal species was not significantly different than their respective controls following application of insecticides. Mean brain AChE activity of grackles was inhibited significantly more than white-winged doves after application of Bolstar, EPN-methyl parathion, and Azodrin and significantly more than that of mourning doves after applications of Bolstar and EPN-methyl parathion. Our data indicate that there were no adverse effects on most brushland wildlife. Exposure was probably dependent upon use of the agricultural fields as feeding or resting sites and only grackles and mourning doves were regularly present in the fields.  相似文献   
280.
Agriculture is a major nonpoint source of phosphorus (P) in the Midwest, but how surface runoff and tile drainage interact to affect temporal concentrations and fluxes of both dissolved and particulate P remains unclear. Our objective was to determine the dominant form of P in streams (dissolved or particulate) and identify the mode of transport of this P from fields to streams in tile-drained agricultural watersheds. We measured dissolved reactive P (DRP) and total P (TP) concentrations and loads in stream and tile water in the upper reaches of three watersheds in east-central Illinois (Embarras River, Lake Fork of the Kaskaskia River, and Big Ditch of the Sangamon River). For all 16 water year by watershed combinations examined, annual flow-weighted mean TP concentrations were >0.1 mg L(-1), and seven water year by watershed combinations exceeded 0.2 mg L(-1). Concentrations of DRP and particulate P (PP) increased with stream discharge; however, particulate P was the dominant form during overland runoff events, which greatly affected annual TP loads. Concentrations of DRP and PP in tiles increased with discharge, indicating tiles were a source of P to streams. Across watersheds, the greatest DRP concentrations (as high as 1.25 mg L(-1)) were associated with a precipitation event that followed widespread application of P fertilizer on frozen soils. Although eliminating this practice would reduce the potential for overland runoff of P, soil erosion and tile drainage would continue to be important transport pathways of P to streams in east-central Illinois.  相似文献   
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