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61.
The juxtaposition of oil and gas wells against the Rocky Mountains on Colorado's Front Range provides a picture of the complicated interaction between Colorado's natural resources above and below ground. As hydraulic fracturing has increased oil and gas development—bringing jobs and money to an already highly sought after amenity‐rich area—it has also increased concerns about the impact on natural amenities, such as water quality and mountain views. Using data on housing sales between 2006 and 2014, we estimate how shale development is capitalized into housing prices in a booming market when households are in close proximity to other natural amenities. We find that shale development negatively impacts house prices, more so for houses with private water and houses that are closer to the mountains, but that competition for land along the Front Range has driven up house prices overall in the region. Our results also suggest the policy responses to shale development may differ for growing, amenity‐rich regions. 相似文献
62.
Woodbury P. B. Arthur M. A. Rubin G. Weinstein L. H. McCune D. C. 《Water, air, and soil pollution》1999,110(3-4):421-432
Selenium, a potentially toxic trace element, is present in coal fly ash and is accumulated by plants growing on ash landfills. Application of gypsum (CaSO4·2H2O) can reduce Se accumulation. The persistence of this effect and the efficacy of repeated gypsum applications were investigated in forbs and grasses on a soil-capped, fly ash landfill near Lansing, New York. Gypsum was applied as a top-dressing at a rate of 0 or 11.2 t ha-1 in 1990 to three plots, and one-half of each of these plots received an additional top dressing of gypsum at 11.2 t ha-1 in 1991, producing four treatments – no gypsum, gypsum only in 1990, gypsum only in 1991, and gypsum in both years. Vegetation was harvested in July and October of 1991 and in July of 1992 and analyzed for Se, S, and Ca. Application of gypsum: (1) decreased Se accumulation by forbs and grasses harvested later in the season; (2) decreased Se accumulation in a subsequent year; (3) produced no further decrease when reapplied in a second year; and (4) did not decrease Se accumulation two years after a single application. The decrease in Se accumulation was not due to dilution caused by S fertilization. Variation in Se accumulation was not explained by variation in the pH and Se concentration of the soil and ash. 相似文献
63.
The investigation was carried out in the Qeren haCarmel forest (35°05′E, 32° 41′N) on Mt. Carmel, in a typical maquis of the Quercus calliprinos—Pistacia palaestina association. Microclimatic measurements were made on five selected sites with western and eastern exposures. The calculation of the index of thermal stress (ITS), expressing the required sweat rate to keep the body temperature constant, and of the thermal sensation (TS), i.e. the feelings of heat or cold, were based on black-body temperatures. Results of ITS and TS for given microclimatic conditions are discussed with a view to the planning and management of maquis for recreation including picnicking, walking in the woods and playing. Silvicultural treatments should create and maintain stands with a crown cover of 70 to 100%, to provide microclimates suitable for recreation all the year round. 相似文献
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The refinement of the product liability litigation process requires a continuing substantive dialogue between the legal and technical communities. The common problem-solving orientation of the two disciplines bodes well for such interaction. We have shared in the exciting beginnings of this legaltechnical interaction (7) and hope that in the field of product liability such joint efforts will lead to a more sophisticated and technologically sound litigation process, one in which the technologist can be true to himself while operating within a strong and responsive adversary system. 相似文献
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External coaptation includes the use of casts, splints, bandages, or slings to help stabilize fractures or luxations, reduce postoperative swelling, or help to protect wounds. Although each of these can be highly effective, it is very important to understand the various types of devices available and the indications for each. Inappropriate use of an external coaptation device can lead to unsatisfactory results. 相似文献
69.
Weinstein NM Blais MC Harris K Oakley DA Aronson LR Giger U 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2007,21(2):287-292
BACKGROUND: Naturally occurring alloantibodies produced against A and B red cell antigens in cats can cause acute hemolytic transfusion reactions. Blood incompatibilities, unrelated to the AB blood group system, have also been suspected after blood transfusions through routine crossmatch testing or as a result of hemolytic transfusion reactions. HYPOTHESIS: Incompatible crossmatch results among AB compatible cats signify the presence of a naturally occurring alloantibody against a newly identified blood antigen in a group of previously never transfused blood donor cats. The associated alloantibody is clinically important based upon a hemolytic transfusion reaction after inadvertent transfusion of red cells expressing this red cell antigen in a feline renal transplant recipient that lacks this red cell antigen. METHODS: Blood donor and nonblood donor cats were evaluated for the presence of auto- and alloantibodies using direct antiglobulin and crossmatch tests, respectively, and were blood typed for AB blood group status. Both standard tube and novel gel column techniques were used. RESULTS: Plasma from 3 of 65 cats and 1 feline renal transplant recipient caused incompatible crossmatch test results with AB compatible erythrocytes indicating these cats formed an alloantibody against a red cell antigen they lack, termed Mik. The 3 donors and the renal transplant recipient were crossmatch-compatible with one another. Tube and gel column crossmatch test results were similar. CONCLUSIONS AND CLINICAL IMPORTANCE: The absence of this novel Mik red cell antigen can be associated with naturally occurring anti-Mik alloantibodies and can elicit an acute hemolytic transfusion reaction after an AB-matched blood transfusion. 相似文献
70.
Ziolo RF Giannelis EP Weinstein BA O'horo MP Ganguly BN Mehrotra V Russell MW Huffman DR 《Science (New York, N.Y.)》1992,257(5067):219-223
A new magnetic material with appreciable optical transmission in the visible region at room temperature has been isolated as a gamma-Fe(2)O(3)/polymer nanocomposite. The synthesis is carried out in an ion-exchange resin at 60 degrees C. Magnetization and susceptibility data demonstrate loading-dependent saturation moments as high as 46 electromagnetic units per gram and superparamagnetism for lower loadings where particle sizes are less than 100 angstroms. Optical absorption studies show that the small-particle form of gamma-Fe(2)O(3) is considerably more transparent to visible light than the single-crystal form. The difference in absorption ranges from nearly an order of magnitude in the "red" spectral region to a factor of 3 at 5400 angstroms. The magnetization of the nanocomposite is greater by more than an order of magnitude than those of the strongest room-temperature transparent magnets, FeBO(3) and FeF(3). 相似文献