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101.
The “triple bottom line” approach emphasizes not only economic goals, but social and environmental objectives as well. The “telework” option—in which employees work from home or a satellite office rather than from a central location—would appear to advance all three of these aims. But a close look at the specifics of teleworking makes clear that more data are needed to determine its ultimate impact. Moreover, despite its apparent advantages, teleworking is gaining acceptance less quickly than might be expected. For these reasons, telework offers a fascinating case study in the difficulties of applying the triple bottom line concept.© 1999 John Wiley & Sons, Inc.  相似文献   
102.
Total mercury concentration was analyzed in 171 lakes from pre-industrial (>30 cm depth; Hgpre-industrial) and present-day sediments (0.5–1 cm; Hgpresent-day). Numerous hot or cold spots of sediment mercury enrichment (Hg EF; Hgpre-industrial/Hgpresent-day) were evident as determined by local tests of autocorrelation, although in most cases, the maximum correlation among sites was not the nearest neighbor, indicating a strong influence of watershed characteristics. Hg EF was correlated with the area of open water (ha) (r = 0.91, p = 0.035), mine tailings (r = 0.94, p = 0.019), and organic deposits in surficial geology of the watershed (r = −0.91, p = 0.034). Through use of local rather than global regression coefficients, R2 increased from 0.20 (p = 0.005) to 0.60 (p = 0.013). A broad spatial pattern (>500 km) observed only in Hgpre-industrial was best explained by mean annual precipitation (shared variance = 3.5%), while finer spatial patterns only observed in Hgpresent-day and Hg EF were best explained by pH (average shared variance = 10.8%).  相似文献   
103.
Redevelopment and reuse plans are often based upon an expedited delineation and remediation life cycle, since delayed reuse usually has economic consequences. It has also become increasingly important to utilize sustainable practices to achieve investigation and remediation goals. In this article, the Triad approach is used to expedite the delineation of a source area within a municipal landfill to complete the remedial effort prior to construction of an urban civic center. The Triad approach uses the three elements of systematic project planning, dynamic work strategy, and real‐time measurement to expedite site characterization (Interstate Technology and Regulatory Council, 2003). In this article, the Triad sampling strategy consisted of two phases. The first phase included in situ screening of soil and groundwater using the membrane interface probe (MIP), and the second phase included confirmatory sampling via vertical profiles in the soil and groundwater. This study found that, using the MIP in a dynamic sampling strategy, a critical element of the Triad approach, combined with the proper placement of confirmatory samples, significantly reduced overall project cost and will expedite the site redevelopment. The use of the Triad approach also contributed to the integration of green and sustainable practices into the project. © 2010 Wiley Periodicals, Inc.  相似文献   
104.
An explosive growth in natural gas production within the last decade has fueled concern over the public health impacts of air pollutant emissions from oil and gas sites in the Barnett and Eagle Ford shale regions of Texas. Commonly acknowledged sources of uncertainty are the lack of sustained monitoring of ambient concentrations of pollutants associated with gas mining, poor quantification of their emissions, and inability to correlate health symptoms with specific emission events. These uncertainties are best addressed not by conventional monitoring and modeling technology, but by increasingly available advanced techniques for real-time mobile monitoring, microscale modeling and source attribution, and real-time broadcasting of air quality and human health data over the World Wide Web. The combination of contemporary scientific and social media approaches can be used to develop a strategy to detect and quantify emission events from oil and gas facilities, alert nearby residents of these events, and collect associated human health data, all in real time or near-real time. The various technical elements of this strategy are demonstrated based on the results of past, current, and planned future monitoring studies in the Barnett and Eagle Ford shale regions.

Implications: Resources should not be invested in expanding the conventional air quality monitoring network in the vicinity of oil and gas exploration and production sites. Rather, more contemporary monitoring and data analysis techniques should take the place of older methods to better protect the health of nearby residents and maintain the integrity of the surrounding environment.  相似文献   

105.
Abstract

In-service diesel engines are a significant source of particulate matter (PM) emissions, and they have been subjected to increasingly strict emissions standards. Consequently, the wide-scale use of some type of particulate filter is expected. This study evaluated the effect of an Engelhard catalyzed soot filter (CSF) and a Rypos electrically heated soot filter on the emissions from in-service diesel engines in terms of PM mass, black carbon concentration, particle-bound polycyclic aromatic hydrocarbon concentration, and size distribution. Both filters capture PM. The CSF relies on the engine's exhaust to reach the catalyst regeneration temperature and oxidize soot, whereas the electrically heated filter contains a heating element to oxidize soot. The filters were installed on several military diesel engines. Particle concentrations and compositions were measured before and after installation of the filter and again after several months of operation. Generally, the CSF removed at least 90% of total PM, and the removal efficiency improved or remained constant after several months of operation. In contrast, the electrical filters removed 44-69% of PM mass. In addition to evaluating the soot filters, the sampling team also compared the results of several real-time particle measurement instruments to traditional filter measurements of total mass.  相似文献   
106.
Holling proposed a four-phase conceptual model of ecosystem dynamics that includes exploitation, conservation, and destructive and renewal components to explain the failure of many natural resource management schemes. The model is drawn as a sideways figure-eight i.e. . There are two dimensions in this model, connectivity (abscissa) and the amount of capital stored in the system (ordinate). This conceptual model has been suggested as a guide to thinking about the impact of climate change on biodiversity, but the two dimensions are insufficient and the alignment of the figure-eight model is problematic when compared with actual data. Kay has adjusted the dimensions of the figure-eight model and renamed the abscissa as exergy stored and the ordinate as exergy consumed. We realign the original figure-eight model, labeling the abscissa as carbon stored and the ordinate as nutrients, such that the relative values of both axes are in qualitative agreement with data from four different studies. This new alignment is then shown to fit relatively well with Holling's original labels. This revision of the figure-eight model brings Holling's model into agreement with observations and provides insight into the linkages between biodiversity and climate change.  相似文献   
107.

Background

Disease severity is important when considering genes for inclusion on reproductive expanded carrier screening (ECS) panels. We applied a validated and previously published algorithm that classifies diseases into four severity categories (mild, moderate, severe, and profound) to 176 genes screened by ECS. Disease traits defining severity categories in the algorithm were then mapped to four severity-related ECS panel design criteria cited by the American College of Obstetricians and Gynecologists (ACOG).

Methods

Eight genetic counselors (GCs) and four medical geneticists (MDs) applied the severity algorithm to subsets of 176 genes. MDs and GCs then determined by group consensus how each of these disease traits mapped to ACOG severity criteria, enabling determination of the number of ACOG severity criteria met by each gene.

Results

Upon consensus GC and MD application of the severity algorithm, 68 (39%) genes were classified as profound, 71 (40%) as severe, 36 (20%) as moderate, and one (1%) as mild. After mapping of disease traits to ACOG severity criteria, 170 out of 176 genes (96.6%) were found to meet at least one of the four criteria, 129 genes (73.3%) met at least two, 73 genes (41.5%) met at least three, and 17 genes (9.7%) met all four.

Conclusion

This study classified the severity of a large set of Mendelian genes by collaborative clinical expert application of a trait-based algorithm. Further, it operationalized difficult to interpret ACOG severity criteria via mapping of disease traits, thereby promoting consistency of ACOG criteria interpretation.
  相似文献   
108.
We documented the spawning patterns of the leopard grouper, Mycteroperca rosacea, from April to June 2005 in the central Gulf of California, Mexico to draw comparisons with other aggregate-spawning groupers and provide information useful for management of their fishery. Adults formed spawning aggregations of 150 to >700 individuals at specific sites, and spawning occurred daily at these sites from late April through early June. Courtship occurred throughout the day, but spawning was restricted to the evening hours. Adults spawned in groups of 6–40 fish, and pair-spawning was not observed. The group-spawning behavior of adults and the gonosomatic indices of mature males (maximum = 7.2%) suggest that sperm competition was present. The site-specificity of leopard grouper spawning aggregations and diel spawning period were typical of most aggregating groupers, and the size and structure of these aggregations was similar to other species in the genus Mycteroperca. Leopard grouper behavior patterns were unusual in that spawning aggregations persisted for extended periods, spawning was not synchronized with the lunar cycle, and adults aggregated during non-spawning periods. The extensive duration and site-specificity of spawning aggregations and the propensity of M. rosacea to form aggregations year-round increases the vulnerability of the species to overfishing. Policies that limit harvest from these aggregations are needed to improve the management of leopard grouper fisheries in the Gulf of California.  相似文献   
109.
Many pteropod species in the eastern tropical North Pacific Ocean migrate vertically each day, transporting organic matter and respiratory carbon below the thermocline. These migrations take species into cold (15–10°?C) hypoxic water (<20?μmol O2 kg?1) at depth. We measured the vertical distribution, oxygen consumption and ammonia excretion for seven species of pteropod, some of which migrate and some which remain in oxygenated surface waters throughout the day. Within the upper 200?m of the water column, changes in water temperature result in a?~60–75?% reduction in respiration for most species. All three species tested under hypoxic conditions responded to low O2 with an additional?~35–50?% reduction in respiratory rate. Combined, low temperature and hypoxia suppress the metabolic rate of pteropods by?~80–90?%. These results shed light on the ways in which expanding regions of hypoxia and surface ocean warming may impact pelagic ecology.  相似文献   
110.
Declining sulphur deposition since the late 1970s has led to increases in pH in lakes and streams of the English Lake District (Cumbria, UK). To determine whether there have been biological responses to the chemical changes, we carried out surveys of stream macroinvertebrates and lake surface sediment diatoms, and compared the results with those from earlier surveys. Macroinvertebrate taxa in five streams (current average pH range 5.1-7.0) sampled in 1999 showed clear changes from those found during 1965/1966 and 1972. For three of the streams, more taxa were present in 1999 than recorded using comparable sampling methods in the 1960s and 1970s, despite lower numbers of individuals being recovered in 1999. Values of the Margalef diversity index could be calculated for both 1965-1972 and 1999 for four of the streams; the index was significantly greater in 1999 (P < 0.001) in three streams, and unchanged in one stream (the most acid). The 1999 survey revealed the presence of acid-sensitive taxa that had been absent in the earlier surveys, notably the three stoneflies Leuctra fusca, L. moselyi and Chloroperla tripunctata. Some taxa that had been present during 1965-1972 were absent in 1999, but few of these were acid-sensitive. Diatoms from the surface sediments of six lakes were classified according to their acid sensitivities. In three of the lakes sampled in 1999 there were more diatoms characteristic of circumneutral waters, and less acidophilic species than had been found in 1983-1985. In the remaining three lakes, no noticeable changes had occurred. Overall, the observed biological changes are qualitatively as expected for the observed increases in pH, and there have been no instances of biological change in the opposite direction. The results support the expectation that changes in freshwater ecological status can be reversed by decreasing the remote emissions of acidifying pollutants.  相似文献   
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