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191.
Research on effects of wind turbines on bats has increased dramatically in recent years because of significant numbers of bats killed by rotating wind turbine blades. Whereas most research has focused on the Midwest and inland portions of eastern North America, bat activity and migration on the Atlantic Coast has largely been unexamined. We used three long-term acoustic monitoring stations to determine seasonal bat activity patterns on the Assateague Island National Seashore, a barrier island off the coast of Maryland, from 2005 to 2006. We recorded five species, including eastern red bats (Lasiurus borealis), big brown bats (Eptesicus fuscus), hoary bats (Lasiurus cinereus), tri-colored bats (Perimyotis subflavus), and silver-haired bats (Lasionycteris noctivagans). Seasonal bat activity (number of bat passes recorded) followed a cosine function and gradually increased beginning in April, peaked in August, and declined gradually until cessation in December. Based on autoregressive models, inter-night bat activity was autocorrelated for lags of seven nights or fewer but varied among acoustic monitoring stations. Higher nightly temperatures and lower wind speeds positively affected bat activity. When autoregressive model predictions were fitted to the observed nightly bat pass totals, model residuals >2 standard deviations from the mean existed only during migration periods, indicating that periodic increases in bat activity could not be accounted for by seasonal trends and weather variables alone. Rather, the additional bat passes were attributable to migrating bats. We conclude that bats, specifically eastern red, hoary, and silver-haired bats, use this barrier island during migration and that this phenomenon may have implications for the development of near and offshore wind energy.  相似文献   
192.

Objectives

To define the prognostic markers of fetal dilated bowel loops.

Methods

National non-interventional study of 133 consecutive prenatal observations of dilated loops including ultrasound examinations, complementary laboratory tests, magnetic resonance imaging (MRI), outcomes, and postnatal diagnosis.

Results

One hundred twenty seven cases were classified according to outcome: Group 1, very severe (n = 43), Group 2, children needing specific care (n = 39), and Group 3, healthy children (n = 45). Prenatal ultrasound scan suggested duodenal obstruction in 30 cases, small bowel obstruction in 81, colonic obstruction in 11, and diffuse dilatation in 5. Diameter of dilated loops did not significantly differ between the groups. A poor prognosis was significantly associated with duodenal obstruction, genetic anomalies (53% vs. 21.8%), including aneuploidies or CFTR gene mutations and abnormal amniotic fluid biochemistry (86.4% vs. 38.7%). A good prognosis was associated with regression of dilatation and normal MRI.

Conclusion

In this study, postnatal outcomes for fetuses with intestinal dilatation were best predicted by assessing the level of obstruction with prenatal ultrasound and MRI, determining the presence of associated malformations, amniotic fluid biochemical and genetic testing, and monitoring for regression of bowel dilatation. These results should help inform future guidelines on the prenatal and neonatal management of congenital intestinal obstruction.  相似文献   
193.
We study the question of environmental equity via generalized linear modeling for the metropolitan New York City region and ask whether, after accounting for socioeconomic status, particular racial/ethnic populations bear a disproportionate burden of hosting environmentally undesirable sites. Our data consist of population demographics for 2216 census tracts linked to 354 environmentally undesirable facilities, including toxic release inventory sites, hazardous waste treatment, storage, and disposal facilities, and other common urban problem sites such as landfills, incinerators, bus garages and sewage treatment plants. Using generalized linear and additive modeling techniques, we find that racial/ethnic demographics, in particular the Hispanic percentage of a tract's population, are significantly associated with the presence of potentially environmentally adverse sites. This leads us to the conclusion that, over the whole metropolitan New York City area, the Hispanic population is proximate to more sites than other populations. At the same time, we find that both Hispanics and African-Americans are more proximate to these sites in the Bronx and Queens. However, we also find indications that Hispanics and African-Americans are less likely to be proximate to the sites in Manhattan. We establish an empirical relationship that warrants additional study in order to establish the causes for the population distribution and whether a basis for a claim of discrimination exists.  相似文献   
194.
The food and feeding ecology of the poorly known southern long-finned pilot whale (Globicephala melas edwardii) was investigated using ecological tracers (muscle and skin δ13C and δ15N, and total mercury, Hg) on individuals from two mass strandings together with at-sea observations of live animals in Kerguelen waters, southern Indian Ocean. Sightings of cetaceans from longliners over 9 years (2003–2012) emphasized the regular occurrence of pilot whales in slope waters surrounding the archipelago. Tissue δ13C values (a proxy of consumer foraging habitat) suggest that pilot whales fed in slope waters and in oceanic subantarctic waters over the last months preceding stranding. Tissue δ15N values and Hg concentration (dietary proxies) indicate a high trophic position (~4.7) for the pilot whales, likely corresponding to a mixed diet of fish and squid (not crustaceans) of undetermined species. Both skin and muscle Hg concentrations were positively and linearly correlated to individual size with no concomitant δ15N changes, which can be interpreted as a progressive Hg accumulation in tissues of individuals throughout life with no parallel dietary shift. Skin and muscle Hg concentrations were linearly and positively related; hence, Hg skin could be used as a proxy of Hg concentration in muscle (a main Hg reservoir of the body). Kerguelen southern long-finned pilot whales were less Hg contaminated than most pilot whale populations studied so far, thus suggesting that they are not at a high risk to Hg-induced damages in the remote islands of the Southern Ocean.  相似文献   
195.
Environmental Science and Pollution Research - To date, no study has linked the environmental and the ecogenotoxicological bioavailability of contaminants to land snails. Yet, understanding the...  相似文献   
196.
Flame retardants in commercial products eventually make their way into the waste stream.Herein the presence of flame retardants in Norwegian landfills, incineration facilities and recycling sorting/defragmenting facilities is investigated. These facilities handled waste electrical and electronic equipment(WEEE), vehicles, digestate, glass, combustibles, bottom ash and fly ash. The flame retardants considered included polybrominated diphenyl ethers(∑BDE-10) as well as dechlorane plus, polybrominated biphenyls, hexabromobenzene,pentabromotoluene and pentabromoethylbenzene(collectively referred to as ∑FR-7). Plastic,WEEE and vehicles contained the largest amount of flame retardants(∑BDE-10: 45,000–210,000 μg/kg; ∑FR-7: 300–13,000 μg/kg). It was hypothesized leachate and air concentrations from facilities that sort/defragment WEEE and vehicles would be the highest. This was supported for total air phase concentrations(∑BDE-10: 9000–195,000 pg/m~3 WEEE/vehicle facilities, 80–900 pg/m~3 in incineration/sorting and landfill sites), but not for water leachate concentrations(e.g., ∑BDE-10: 15–3500 ng/L in WEEE/Vehicle facilities and 1–250 ng/L in landfill sites). Landfill leachate exhibited similar concentrations as WEEE/vehicle sorting and defragmenting facility leachate. To better account for concentrations in leachates at the different facilities, waste-water partitioning coefficients, Kwastewere measured(for the first time to our knowledge for flame retardants). WEEE and plastic waste had elevated Kwastecompared to other wastes, likely because flame retardants are directly added to these materials. The results of this study have implications for the development of strategies to reduce exposure and environmental emissions of flame retardants in waste and recycled products through improved waste management practices.  相似文献   
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