508 research outputs found

    The Assessment of Environmental Impacts at Nuclear Power Generating Stations

    Get PDF
    The Federal actions that are required with regard to nuclear power stations are the granting of a construction permit and later the issuance of a license to operate the station. Since the Atomic Energy Commission (AEC) is responsible for these actions, the Commission is also responsible for preparation of an environmental statement on the proposed actions. The National Laboratories including the one at Oak Ridge are used as part of the staff in preparing the statements. The staff makes an independent determination of the plant effluents and their dispersions. The impact of these and plant construction on the environment are assessed by the staff. Alternatives to the proposed plant are similarly evaluated as are alternative subsystems such as the proposed waste heat removal system. Finally the environmental costs are compared with the benefits. A number of assessments have resulted in required changes in heat removal systems, chemical treatment procedures and radioactive waste systems to reduce the impacts to an acceptable level. The benefits of the modified stations have been shown to outweigh the environmental costs

    Distribution of priority grassland bird habitats in the Prairie Pothole Region of Canada

    Get PDF
    Grassland ecosystems and the species that rely on them are one of the most urgent habitat conservation concerns in North America. Fundamental to any landscape conservation efforts is the identification of priority habitats to help target management efforts. Many avian species associated with prairie ecosystems have experienced population declines along with continued loss of prairie habitats. Additionally, given the long history of research in avian systems and the close grassland associations of some species, birds are excellent candidate taxa for the identification of priority habitats and can provide an informed starting point for multispecies assessments. We used data from the North American Breeding Bird Survey (1997-2014) to develop species distribution models for 15 grassland bird species across the Prairie Pothole Region of Canada. Model performance varied widely across species. Ten species demonstrated good model performance (average Boyce Index > 0.64 across 5-fold cross validation). We used these 10 species to assess the influence of habitat covariates on the relative probability of occurrence, to compare the spatial scales of selection, and to generate multispecies habitat priority maps. Of the nine habitat covariates considered, most species predictably demonstrated positive associations with grassland habitats and avoidance of areas of high tree and shrub cover. Two covariates representing wetland abundance were also frequently included in the top models. The area covered by wetlands (w.area) was present in the top model for 5 of 10 species with a consistently estimated negative coefficient. However, a covariate, which represented the number of wetland basins (w.basins), was present in the top model for 8 of 10 species with an estimated positive coefficient for all but 1 species, representing a preference for more heterogeneous wetland landscapes. The larger spatial scales we considered tended to have greater explanatory power than smaller spatial scales and were thus more prevalent in the top models. The multispecies priority habitat maps that we produced can be used for future assessments of potential habitat management actions. Our work provides a critical foundation for the incorporation of grassland bird conservation goals into on-going landscape-planning initiatives in the Prairie Pothole Region of Canada

    A novel structure of secondary alcohol derived from (+)-&#916;<SUP>3</SUP>-carene with pseudo three-fold symmetry

    Get PDF
    The crystal structure of C12OH20 (lR-6R-4R-2 R-3,7,7-trimethyl-4-(2-hydroxyethyl) bicyclo [4.1.0] hept-2-ene) has been determined by X-ray diffraction. The compound crystallizes in space group P212121 witha = 5.893(1),b = 22.572(2), c = 26.164(3) &#197;,V = 3480.3 &#197;3, Z= 12. The structure was solved by modified direct methods and refined to anR value of 0.081 for 607 unique reflections. Each asymmetric unit has three molecules which are held together through intermolecular hydrogen bonds resulting in a novel spiral-type arrangement of molecules. The six-membered ring has a half-chair conformation

    Intermittent Hypoxia-Induced Cognitive Deficits Are Mediated by NADPH Oxidase Activity in a Murine Model of Sleep Apnea

    Get PDF
    Background: In rodents, exposure to intermittent hypoxia (IH), a hallmark of obstructive sleep apnea (OSA), is associated with neurobehavioral impairments, increased apoptosis in the hippocampus and cortex, as well as increased oxidant stress and inflammation. Excessive NADPH oxidase activity may play a role in IH-induced CNS dysfunction. Methods and Findings: The effect of IH during light period on two forms of spatial learning in the water maze and well as markers of oxidative stress was assessed in mice lacking NADPH oxidase activity (gp91phox _/Y) and wild-type littermates. On a standard place training task, gp91phox _/Y displayed normal learning, and were protected from the spatial learning deficits observed in wild-type littermates exposed to IH. Moreover, anxiety levels were increased in wild-type mice exposed to IH as compared to room air (RA) controls, while no changes emerged in gp91phox _/Y mice. Additionally, wild-type mice, but not gp91phox _/Y mice had significantly elevated levels of NADPH oxidase expression and activity, as well as MDA and 8-OHDG in cortical and hippocampal lysates following IH exposures. Conclusions: The oxidative stress responses and neurobehavioral impairments induced by IH during sleep are mediated, at least in part, by excessive NADPH oxidase activity, and thus pharmacological agents targeting NADPH oxidase may provid

    Landscape characteristics influencing the genetic structure of greater sage-grouse within the stronghold of their range: a holistic modeling approach

    Get PDF
    Given the significance of animal dispersal to population dynamics and geographic variability, understanding how dispersal is impacted by landscape patterns has major ecological and conservation importance. Speaking to the importance of dispersal, the use of linear mixed models to compare genetic differentiation with pairwise resistance derived from landscape resistance surfaces has presented new opportunities to disentangle the menagerie of factors behind effective dispersal across a given landscape. Here, we combine these approaches with novel resistance surface parameterization to determine how the distribution of high- and low-quality seasonal habitat and individual landscape components shape patterns of gene flow for the greater sage-grouse (Centrocercus urophasianus) across Wyoming. We found that pairwise resistance derived from the distribution of low-quality nesting and winter, but not summer, seasonal habitat had the strongest correlation with genetic differentiation. Although the patterns were not as strong as with habitat distribution, multivariate models with sagebrush cover and landscape ruggedness or forest cover and ruggedness similarly had a much stronger fit with genetic differentiation than an undifferentiated landscape. In most cases, landscape resistance surfaces transformed with 17.33-km-diameter moving windows were preferred, suggesting small-scale differences in habitat were unimportant at this large spatial extent. Despite the emergence of these overall patterns, there were differences in the selection of top models depending on the model selection criteria, suggesting research into the most appropriate criteria for landscape genetics is required. Overall, our results highlight the importance of differences in seasonal habitat preferences to patterns of gene flow and suggest the combination of habitat suitability modeling and linear mixed models with our resistance parameterization is a powerful approach to discerning the effects of landscape on gene flow.U.S. Bureau of Land ManagementU.S. Geological SurveyWyoming Game and Fish Departmen

    The data hungry home

    Get PDF
    It's said that the pleasure is in the giving, not the receiving. This belief is validated by how humans interact with their family, friends and society as well as their gardens, homes, and pets. Yet for ubiquitous devices, this dynamic is reversed with devices as the donors and owners as the recipients. This paper explores an alternative paradigm where these devices are elevated, becoming members of Data Hungry Homes, allowing us to build relationships with them using the principles that we apply to family, pets or houseplants. These devices are developed to fit into a new concept of the home, can symbiotically interact with us and possess needs and traits that yield unexpected positive or negative outcomes from interacting with them. Such relationships could enrich our lives through our endeavours to β€œfeed” our Data Hungry Homes, possibly leading us to explore new avenues and interactions outside and inside the home

    Designing Hybrid Gifts

    Get PDF
    Hybrid gifting combines physical artefacts and experiences with digital interactivity to generate new kinds of gifts. Our review details how gifting is a complex social phenomenon and how digital gifting is less engaging than physical gifting for both givers and receivers. Employing a Research Through Design approach, we developed a portfolio of four hybrid gifting experiences: an augmented advent calendar; edible music tracks; personalised museum tours; and a narrated city walk. Our reflection addresses three concepts: hybrid wrapping where physical gifts become wrapped in digital media and vice versa; the importance of effortful interactions that are visible and pleasurable; and the need to consider social obligation, including opportunities for acknowledgement and reciprocation, dealing with embarrassment, and recognising the distinction between giving and sharing. Our concepts provide guidance to practitioners who wish to design future gifting experiences while helping HCI researchers engage with the concept of gifting in a nuanced way

    A Global Census of Fission Yeast Deubiquitinating Enzyme Localization and Interaction Networks Reveals Distinct Compartmentalization Profiles and Overlapping Functions in Endocytosis and Polarity

    Get PDF
    Proteomic, localization, and enzymatic activity screens in fission yeast reveal how deubiquitinating enzyme localization and function are tuned
    • …
    corecore