4,764 research outputs found
Electricity deregulation and the valuation of visibility loss in wilderness areas: A research note.
Visibility in most wilderness areas in the northeastern United States has declined substantially since the 1970s. As noted by Hill et al. (2000), despite the 1977 Clean Air Act and subsequent amendments, human induced smog conditions are becoming increasingly worse. Average visibility in class I airsheds, such as the Great Gulf Wilderness in New Hampshireās White Mountains, is now about one-third of natural conditions. A particular concern is that deregulation of electricity production could result in further degradation because consumers may switch to lower cost fossil fuel generation (Harper 2000). To the extent that this system reduces electricity costs, it may also affect firm location decisions (Halstead and Deller 1997). Yet, little is known about the extent to which consumers are likely to make tradeoffs between electric bills and reduced visibility in nearby wilderness areas. This applied research uses a contingent valuation approach in an empirical case study of consumersā tradeoffs between cheaper electric bills and reduced visibility in New Hampshireās White Mountains. We also examine some of the problems associated with uncertainty with this type of analysis; that is, how confident respondents are in their answers to the valuation questions. Finally, policy implications of decreased visibility due to electricity deregulation are discussed
TINKERING WITH VALUATION ESTIMATES: IS THERE A FUTURE FOR WILLINGNESS TO ACCEPT MEASURES?
This paper examines various methods proposed in the literature to calibrate welfare measures, especially willingness to accept and willingness to pay, derived from contingent valuation surveys. Through simulation and a case study, we hope to provide guidance for empirical welfare measurement in response to the theoretical dispute regarding WTA/WTP disparities.Resource /Energy Economics and Policy,
Gender Differences in Student Engagement Among African American Undergraduates at Historically Black Colleges and Universities
Differences in student engagement between women and men at historically Black colleges and universities (HBCUs) are examined in this study. Data were collected from 1,167 African American undergraduate students at 12 four-year HBCUs that participated in the National Survey of Student Engagement. Controlling for several factors that might obscure gender differences, the results counter previous research regarding gender gaps on HBCU campuses by illustrating that African American women enjoy an equally engaging experience as their same-race male counterparts
Structural imaging biomarkers of sudden unexpected death in epilepsy.
Sudden unexpected death in epilepsy is a major cause of premature death in people with epilepsy. We aimed to assess whether structural changes potentially attributable to sudden death pathogenesis were present on magnetic resonance imaging in people who subsequently died of sudden unexpected death in epilepsy. In a retrospective, voxel-based analysis of T1 volume scans, we compared grey matter volumes in 12 cases of sudden unexpected death in epilepsy (two definite, 10 probable; eight males), acquired 2 years [median, interquartile range (IQR) 2.8] before death [median (IQR) age at scanning 33.5 (22) years], with 34 people at high risk [age 30.5 (12); 19 males], 19 at low risk [age 30 (7.5); 12 males] of sudden death, and 15 healthy controls [age 37 (16); seven males]. At-risk subjects were defined based on risk factors of sudden unexpected death in epilepsy identified in a recent combined risk factor analysis. We identified increased grey matter volume in the right anterior hippocampus/amygdala and parahippocampus in sudden death cases and people at high risk, when compared to those at low risk and controls. Compared to controls, posterior thalamic grey matter volume, an area mediating oxygen regulation, was reduced in cases of sudden unexpected death in epilepsy and subjects at high risk. The extent of reduction correlated with disease duration in all subjects with epilepsy. Increased amygdalo-hippocampal grey matter volume with right-sided changes is consistent with histo-pathological findings reported in sudden infant death syndrome. We speculate that the right-sided predominance reflects asymmetric central influences on autonomic outflow, contributing to cardiac arrhythmia. Pulvinar damage may impair hypoxia regulation. The imaging findings in sudden unexpected death in epilepsy and people at high risk may be useful as a biomarker for risk-stratification in future studies
Factors Influencing Northern Bobwhite Hunter Success on a Public Wildlife Management Area in Kentucky
Hunter success is a critical measure of northern bobwhite (Colinus virginianus) restoration. Understanding the factors influencing hunter success can guide wildlife agencies in efforts to improve success and satisfaction and sustain hunter support of conservation initiatives. We compared use of vegetation types by radiomarked bobwhite (n = 30 coveys) and hunting dogs (n = 241) equipped with Global Positioning System collars during the 2014ā2015 quail hunting season on Peabody Wildlife Management Area in western Kentucky. We surveyed hunting parties (n = 252) immediately after their hunt to determine success (flushed bobwhite) and gather hunt-party characteristics. We used associated habitat metrics from the dog track, weather variables, hunter and dog characteristics (e.g., age, experience), and hunt metrics (e.g., hours hunted, no. of dogs) to determine factors that influenced hunt success. Dogs used winter wheat firebreaks more than bobwhite regardless of time of day, forested areas more than bobwhite in the morning (0700ā1000 hr) and midday (1000ā1300 hr), disked areas more than bobwhite during midday, and open herbaceous areas less than bobwhite during morning and midday. The probability of success was positively influenced by number of dogs and hours hunted and negatively influenced by proportion of the hunt track in disked areas. Also, hunter success was greater in November compared with December and January. Our results indicated some key features associated with bobwhite habitat (open areas) may be underexploited by hunters, whereas other features (disked areas, firebreaks, and forested areas) may be overexploited. However, success was influenced primarily by factors that may be related to covey avoidance behavior resulting from substantial hunting pressure rather than where hunters selected to hunt. Lower bobwhite encounter rates (coveys flushed/hour) could cause hunter support to wane and bias hunting data as an indicator of population abundance
THE POTENTIAL ECONOMIC RENT IN THE UNITED STATES FROM CO 2 ABATEMENT POLICIES
Increasingly, climate change has come to the fore as an environmental issue with nearly universal agreement that the current trend is unsustainable and must be addressed. Of particular concern is the amount of carbon dioxide (CO2) emitted into the atmosphere, the primary contributor to climate change through the combustion of fossil fuels. In the United States alone, CO2 emissions account for approximately 85% of all U.S. greenhouse gas emissions, most of which come from fossil fuels (EPA, 2008). Reducing the risk of the damage caused by climate change requires the world to substantially reduce CO2 production. In the past five to ten years several proposals to address climate change have been suggested; most prominently cap-and-trade and carbon taxes. These market-based approaches differ from the traditional command-and-control policies, such as Corporate Average Fuel Efficiency (CAFĆ) standards which mandate minimum fleet mileage standards for vehicles sold in the United States, by providing firms a cost-effective and flexible form of environmental regulation. Other benefits also exist, such as technological innovation to reduce greenhouse gas emissions and potential revenue sources for governments; the more a firm emits CO2, the more they pay, either in taxes or through purchased emission permits.
Detection of two poleroviruses infecting garlic (Allium sativum) in Australia
Two near complete polerovirus genomes were assembled using high throughput sequencing (HTS) data from two separate samples of garlic cultivar āGlenlargeā grown in Gatton, Queensland, Australia. Whole genome sequence comparisons showed that one contig shared 96.7% nucleotide identity with phasey bean mild yellows virus (MT966032.1) and the other, 99.8% nucleotide identity with turnip yellows virus (MT586581.1). Phylogenetic analyses further revealed that the isolates fell within the PBMYV group 2 and TuYV group 2 clades, respectively. This is the first report of these poleroviruses infecting garlic
Northern Bobwhite Survival Related to Movement on a Reclaimed Surface Coal Mine
Reclaimed coal mines represent opportunity to provide large tracts of early succession habitat essential to northern bobwhite (Colinus virginianus) populations. However, little research has been conducted to explore the potential of reclaimed mine sites and examine bobwhite ecology on these unique areas. Reclaimed mines in Kentucky were planted to non-native species, such as sericea lespedeza (Lespedeza cuneata) and tall fescue (Festuca arundinacea), which do not provide suitable structure for northern bobwhite brood-rearing and movement. Fallow disking (in blocks and linear firebreaks) and planting food plots are part of current management efforts to improve food availability and habitat structure for broods. We trapped and radiomarked 266 northern bobwhites between April 2010 and September 2011 on Peabody Wildlife Management Area, a 3,330-ha reclaimed coal mine in western Kentucky, USA to investigate the effects of current management practices on movement and survival. We calculated seasonal daily movement as the Euclidean distance from a location on day 1 to day 2. Breeding season (1 Apr-30 Sep) movement averaged 128 m in 2010 and 147 m in 2011. Daily movement averaged 163 m during the 2010ā2011 non-breeding (1 Oct-31 Mar) season. Multiple regression analysis indicated annual food plots, disk blocks, firebreaks, and roads did not explain variation within daily movement regardless of season (R2 0.04). Individual bird/covey, precipitation, hours between locations, and average temperature also poorly explained movement variation. We used Program MARK to model the effect of season, year, mean daily movement, mean distance to annual food plots, disk blocks, firebreaks, and roads on survival. The season (breeding/non-breeding) model explained 81% of the variation in survival, and the year model explained 13%, suggesting management was not driving survival. We do not believe disking should be discontinued, although it did not influence movement, as it can improve vegetation structure important to nest-site selection and broods
Elemental concentrations in the seed of mutants and natural variants of Arabidopsis thaliana grown under varying soil conditions
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