1,477 research outputs found

    The influence of landscape context on the production of cultural ecosystem services

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    Recent efforts to apply sustainability concepts to entire landscapes have seen increasing interest in approaches that connect socioeconomic and biophysical systems. Evaluating these connections through a cultural ecosystem services lens clarifies how different spatiotemporal scales and levels of organisation influence the production of cultural benefits. Currently, however, the effects of multi-level and multi-scale ecological variation on the production of cultural benefits have not yet been disentangled. Objectives To quantify the amount of variation in cultural ecosystem service provision by birds to birders that is due to landscape-level attributes. Methods We used data from 293 birding routes and 101 different birders in South African National Parks to explore the general relationships between birder responses to bird species and environmental conditions, bird-related observations, the biophysical attributes of the landscape and their effect on bird-related cultural benefits. Results Biophysical attributes (particularly biome, vegetation type, and variance in elevation) significantly increased the percentage of variance explained in birder benefits from 57 to 65%, demonstrating that birder benefits are derived from multi-level (birds to ecosystems) and multi-scale (site to landscape) social and ecological interactions. Conclusions Landscape attributes influence people's perceptions of cultural ecosystem service provision by individual species. Recognition of the complex, localised and inextricable linkage of cultural ecosystem services to biophysical attributes can improve our understanding of the landscape characteristics that affect the supply and demand of cultural ecosystem services

    The role of socio-demographic characteristics in mediating relationships between people and nature

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    Research on ecosystem services has focused on their availability or supply and often takes a socially-aggregated approach that assumes a single human community of identical beneficiaries. However, people's ability to derive benefits from ecosystem services can differ strongly across societal groups. Access to ecosystem services can be related to socio-demographic characteristics such as material wealth, gender, education and age. Developing environmental management that does not have unequal impacts on different groups thus depends on taking a socially-disaggregated approach to assessing perceptions of ecosystem services. We explored how socio-demographic characteristics relate to cultural functional groups based on perceived bird traits. Using perception data on 491 bird species from 401 respondents along urban-rural gradients in South Africa, we found that socio-demographic characteristics are strongly associated with cultural functional groups based on perceived bird traits. Our results provide a starting point for understanding heterogeneity in the benefits from avian ecosystem services and how perceptions of cultural functional groups vary across societal groups

    Social adaptation can reduce the strength of social–ecological feedbacks from ecosystem degradation

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    Feedbacks between people and ecosystems are central to the study of social–ecological systems (SES) but remain poorly understood. It is commonly assumed that changes in ecosystems leading to a reduction in ecosystem services will trigger human responses that seek to restore service provision. Other responses are possible, however, but remain less studied. We evaluated the effect of environmental change, specifically the degradation of coral reefs, on the supply of and demand for a cultural ecosystem service (CES); that is, recreation. We found that declines in coral cover reduced demand for recreational ecosystem services but had no apparent effect on the benefits received from recreation. While this finding seems counter-intuitive given previous experimental data that suggest ecosystem quality affects people's satisfaction, our analysis suggests that social adaptation could have mediated the anticipated negative impact of environmental change on CES benefits. We propose four mechanisms that may explain this effect and that require further research: spatial diversification; (service) substitution; shifting baselines; and time-delayed effects. Our findings emphasize the importance of human culture and perception as influences on human responses to environmental change, and the relevance of the more subjective elements of social systems for understanding social–ecological feedbacks

    Measure Guideline: Buried and/or Encapsulated Ducts

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    Buried and/or encapsulated ducts (BEDs) are a class of advanced, energy-efficiency strategies intended to address the significant ductwork thermal losses associated with ducts installed in unconditioned attics. BEDs are ducts installed in unconditioned attics that are covered in loose-fill insulation and/or encapsulated in closed cell polyurethane spray foam insulation. This Measure Guideline covers the technical aspects of BEDs as well as the advantages, disadvantages, and risks of BEDs compared to other alternative strategies. This guideline also provides detailed guidance on installation of BEDs strategies in new and existing homes through step-by-step installation procedures. This Building America Measure Guideline synthesizes previously published research on BEDs and provides practical information to builders, contractors, homeowners, policy analysts, building professions, and building scientists. Some of the procedures presented here, however, require specialized equipment or expertise. In addition, some alterations to duct systems may require a specialized license. Persons implementing duct system improvements should not go beyond their expertise or qualifications. This guideline provides valuable information for a building industry that has struggled to address ductwork thermal losses in new and existing homes. As building codes strengthen requirements for duct air sealing and insulation, flexibility is needed to address energy efficiency goals. While ductwork in conditioned spaces has been promoted as the panacea for addressing ductwork thermal losses, BEDs installations approach - and sometimes exceed - the performance of ductwork in conditioned spaces

    Radiation-hard ASICs for optical data transmission in the ATLAS pixel detector

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    We have developed two radiation-hard ASICs for optical data transmission in the ATLAS pixel detector at the LHC at CERN: a driver chip for a Vertical Cavity Surface Emitting Laser (VCSEL) diode for 80 Mbit/s data transmission from the detector, and a Bi-Phase Mark decoder chip to recover the control data and 40 MHz clock received optically by a PIN diode. We have successfully implemented both ASICs in 0.25 um CMOS technology using enclosed layout transistors and guard rings for increased radiation hardness. We present results from prototype circuits and from irradiation studies with 24 GeV protons up to 57 Mrad (1.9 x 10e15 p/cm2).Comment: 8th Tropical Seminar on Innovative Particle and Radiation Detectors, Siena, Italy (2002

    Retrofitting the Southeast. The Cool Energy House

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    The Consortium for Advanced Residential Buildings has provided the technical engineering and building science support for a highly visible demonstration home in connection with the National Association of Home Builders' International Builders Show. The two previous projects, the Las Vegas net-zero ReVISION House and the 2011 VISION and ReVISION Houses in Orlando, met goals for energy efficiency, cost effectiveness, and information dissemination through multiple web-based venues. This project, which was unveiled at the 2012 International Builders Show in Orlando on February 9, is the deep energy retrofit Cool Energy House (CEH). The CEH began as a mid-1990s two-story traditional specification house of about 4,000 ft2 in the upscale Orlando suburb of Windermere

    Evaluation of the U.S. EPA/OSWER Preliminary Remediation Goal for Perchlorate in Groundwater: Focus on Exposure to Nursing Infants

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    BACKGROUND: Perchlorate is a common contaminant of drinking water and food. It competes with iodide for uptake into the thyroid, thus interfering with thyroid hormone production. The U.S. Environmental Protection Agency’s Office of Solid Waste and Emergency Response (OSWER) set a groundwater preliminary remediation goal (PRG) of 24.5 ÎŒg/L to prevent exposure of pregnant women that would affect the fetus. This does not account for the greater exposure that is possible in nursing infants or for the relative source contribution (RSC), a factor normally used to lower the PRG due to nonwater exposures. OBJECTIVES: Our goal was to assess whether the OSWER PRG protects infants against exposures from breast-feeding, and to evaluate the perchlorate RSC. METHODS: We used Monte Carlo analysis to simulate nursing infant exposures associated with the OSWER PRG when combined with background perchlorate. RESULTS: The PRG can lead to a 7-fold increase in breast milk concentration, causing 90% of nursing infants to exceed the reference dose (RfD) (average exceedance, 2.8-fold). Drinking-water perchlorate must be < 6.9 ÎŒg/L to keep the median, and < 1.3 ÎŒg/L to keep the 90th-percentile nursing infant exposure below the RfD. This is 3.6- to 19-fold below the PRG. Analysis of biomonitoring data suggests an RSC of 0.7 for pregnant women and of 0.2 for nursing infants. Recent data from the Centers for Disease Control and Prevention (CDC) suggest that the RfD itself needs to be reevaluated because of hormonal effects in the general population. CONCLUSIONS: The OSWER PRG for perchlorate can be improved by considering infant exposures, by incorporating an RSC, and by being responsive to any changes in the RfD resulting from the new CDC data

    An Animal Cell Mutant With a Deficiency in Acyl/Alkyl-Dihydroxyacetone- Phosphate Reductase Activity. Effects on the Biosynthesis of Ether-Linked and Diacyl Glycerolipids

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    In the accompanying paper (James, P. F., and Zoeller, R. A. (1997) J. Biol. Chem. 272, 23532-23539), we reported the isolation of a series of mutants from the fibroblast-like cell line, CHO-K1, that are deficient in the incorporation of the long chain fatty alcohol, hexadecanol, into complex lipids. All but one of these mutants, FAA.K1B, were deficient in long-chain- fatty alcohol oxidase (FAO) activity. We have further characterized this FAO+ isolate. FAA.K1B cells displayed a 40% decrease in [9,103H]hexadecanol uptake when compared with the parent strain. Although incorporation of hexadecanol into the phospholipid fraction was decreased by 52%, the cells accumulated label in alkylglycerol (20-fold over wild type). The increase in 1-alkylglycerol labeling corresponded to a 4-fold increase in alkylglycerol mass. Short term labeling with 32P1 showed a 45-50% decrease in overall phospholipid biosynthesis in FAA.K1B. Both diacyl- and ether-linked species were affected, suggesting a general defect in phospholipid biosynthesis. Mutant cells were able to partially compensate for the decreased biosynthesis by decreasing the turnover of the phospholipid pools. The primary lesion in FAA.K1B was identified as a 95% reduction in acyl/alkyl-dihydroxyacetone- phospbate reductase activity. Whole cell homogenates from FAA.K1B were unable to reduce either acyl-dihydroxyacetone phosphate (DHAP) or alkyl-DHAP, supporting the notion that the reduction of these two compounds is catalyzed by a single enzyme. These data suggest that the biosynthesis of diacyl phospholipids, in Chinese hamster ovary cells, begins with the acylation of dihydroxyacetone phosphate as well as glycero-3-phosphate and that the \u27DHAP pathway\u27 contributes significantly to diacyl glycerolipid biosynthesis. Also, the severe reduction in acyl/alkyl-DHAP reductase activity in FAA.K1B resulted in only a moderate decrease in ether lipid biosynthesis. These latter data together with the observed increase in alkylglycerol levels sup port the existence of a shunt pathway that is able to partially bypass the enzymatic lesion

    Insights from twenty years of comparative research in Pacific Large Ocean States

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    Under global environmental change, understanding the interactions between people and nature has become critical for human survival. Comparative research can identify trends within social-ecological systems providing key insights for both environmental and developmental research. Island systems, with clear land boundaries, have been proposed as ideal case studies for comparative research, but it is unclear to what extent their potential has been fulfilled. To summarize existing research and identify potential gaps and new directions, we reviewed comparative environmental and developmental research on Pacific Large Ocean States. A diversity of case study locations and research themes were addressed within the sample of reviewed studies. Within the reviewed literature climate change, energy infrastructure, trade and fisheries were key themes of environmental and developmental research compared between island systems. Research was biased towards wealthier Pacific Large Ocean States and those with a relatively higher degree of socio-economic development. Our review highlights the potential value of a stronger a priori inclusion of spatial scale and conceptual frameworks, such as spatial resilience, to facilitate generalization from case studies
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