995 research outputs found
PUBLIC CONSERVATION LAND AND EMPLOYMENT GROWTH IN THE NORTHERN FOREST REGION
As with many environmental issues, debates about increasing public conservation lands in the Northern Forest region frequently center on a perceived tradeoff between jobs and the environment. In particular, opponents of conservation lands often argue that employment will decline significantly when land is diverted from commodity-oriented uses such as wood products production. To evaluate this claim, we estimate a model of simultaneous employment and net migration growth using data on the 92 non-metropolitan counties comprising the region. Growth in employment and net migration are measured over the period 1990 to 1997 and the set of exogenous variables includes the 1990 share of the county land base in public conservation uses. We find that net migration rates were systematically higher in counties with more conservation lands, but the effects are relatively small. Public conservation lands were found to have no systematic effect on employment growth over the 1990 to 1997 period. Two extensions are considered. We examine the separate effects of preservationist and multiple-use lands. We also identify a "natural experiment" involving changes in national forest management that allows us to estimate the effects of diverting private forestland to public conservation uses. Our central conclusions are that existing public conservation lands have a positive, but small, effect on employment and migration in the Northern Forest region and that, over the range of our data, employment and migration are unlikely to be affected by timber harvest reductions resulting from the establishment of new conservation lands.Labor and Human Capital, Land Economics/Use,
Modelportefeuilles:performance en strategieën
Modelportefeuilles: performance en strategieë
Priority monism and essentiality of fundamentality: a reply to Steinberg
Steinberg has recently proposed an argument against Schafferâs priority monism. The argument assumes the principle of Necessity of Monism, which states that if priority monism is true, then it is necessarily true. In this paper, I argue that Steinbergâs objection can be eluded by giving up Necessity of Monism for an alternative principle, that I call Essentiality of Fundamentality, and that such a principle is to be preferred to Necessity of Monism on other grounds as well
Association between Posttraumatic Stress Disorder and Inflammation: A Twin Study
The association of posttraumatic stress disorder (PTSD) with cardiovascular disease risk may be mediated by inflammation. Our objective was to examine the association between PTSD and measures of inflammation and to determine whether these associations are due to shared familial or genetic factors. We measured lifetime history of PTSD using the Structured Clinical Interview for DSM-IV in 238 male middle-aged military veteran twin pairs (476 individuals), selected from the Vietnam Era Twins Registry, who were free of cardiovascular disease at baseline. We assessed inflammation using levels of high-sensitivity C-reactive protein (hsCRP), interleukin 6 (IL-6), fibrinogen, white blood cells, vascular cell adhesion molecule-1, and intercellular adhesion molecule-1 (ICAM-1). Geometric mean levels and percent differences by PTSD were obtained from mixed-model linear regression analyses with adjustment for potential confounders. Within-pair analysis was conducted to adjust for shared family environment and genetics (monozygotic pairs). Overall, 12.4% of participants had a lifetime history of PTSD. Adjusted mean levels of hsCRP and ICAM-1 were significantly higher among those with vs. without PTSD [hsCRP: 1.75 vs. 1.31 mg/l (33% difference); ICAM-1: 319 vs. 293 ng/ml (9% difference)]. Adjustment for depression rendered the association of PTSD with hsCRP non-statistically significant. For IL-6, no consistent association was seen. Within-pair analysis produced associations that were similar in direction for all three markers but lesser in magnitude for hsCRP and IL-6. There was no evidence of interaction by zygosity. Elevated hsCRP and ICAM-1 are associated with PTSD, and these associations may be confounded by shared non-genetic, antecedent familial and environmental factors
Economic-based projections of future land use in the conterminous United States under alternative policy scenarios
Land-use change significantly contributes to biodiversity loss, invasive species spread, changes in biogeochemical cycles, and the loss of ecosystem services. Planning for a sustainable future requires a thorough understanding of expected land use at the fine spatial scales relevant for modeling many ecological processes and at dimensions appropriate for regional or national-level policy making. Our goal was to construct and parameterize an econometric model of land-use change to project future land use to the year 2051 at a fine spatial scale across the conterminous United States under several alternative land-use policy scenarios. We parameterized the econometric model of land-use change with the National Resource Inventory (NRI) 1992 and 1997 land-use data for 844 000 sample points. Land-use transitions were estimated for five land-use classes (cropland, pasture, range, forest, and urban). We predicted land-use change under four scenarios: business-as-usual, afforestation, removal of agricultural subsidies, and increased urban rents. Our results for the business-as-usual scenario showed widespread changes in land use, affecting 36% of the land area of the conterminous United States, with large increases in urban land (79%) and forest (7%), and declines in cropland (\-16%) and pasture (\-13%). Areas with particularly high rates of land-use change included the larger Chicago area, parts of the Pacific Northwest, and the Central Valley of California. However, while land-use change was substantial, differences in results among the four scenarios were relatively minor. The only scenario that was markedly different was the afforestation scenario, which resulted in an increase of forest area that was twice as high as the business-as-usual scenario. Land-use policies can affect trends, but only so much. The basic economic and demographic factors shaping land-use changes in the United States are powerful, and even fairly dramatic policy changes, showed only moderate deviations from the business-as-usual scenario. Given the magnitude of predicted land-use change, any attempts to identify a sustainable future or to predict the effects of climate change will have to take likely land-use changes into account. Econometric models that can simulate land-use change for broad areas with fine resolution are necessary to predict trends in ecosystem service provision and biodiversity persistence. © 2012 by the Ecological Society of America
Recommended from our members
Primary care physicians' perceptions of barriers and facilitators to management of chronic kidney disease: A mixed methods study.
BackgroundGiven the high prevalence of chronic kidney disease (CKD), primary care physicians (PCPs) frequently manage early stage CKD. Nonetheless, there are challenges in providing optimal CKD care in the primary care setting. This study sought to understand PCPs' perceptions of barriers and facilitators to the optimal management of CKD.Study designMixed methods study.Settings and participantsCommunity-based PCPs in four US cities: Baltimore, MD; St. Louis, MO; Raleigh, NC and San Francisco, CA.MethodologyWe used a self-administered questionnaire and conducted 4 focus groups of PCPs (n = 8 PCPs/focus group) in each city to identify key barriers and facilitators to management of patients with CKD in primary care.Analytic approachWe conducted descriptive analyses of the survey data. Major themes were identified from audio-recorded interviews that were transcribed and coded by the research team.ResultsOf 32 participating PCPs, 31 (97%) had been in practice for >10 years, and 29 (91%) practiced in a non-academic setting. PCPs identified multiple barriers to managing CKD in primary care including at the level of the patient (e.g., low awareness of CKD, poor adherence to treatment recommendations), the provider (e.g., staying current with CKD guidelines), and the health care system (e.g., inflexible electronic medical record, limited time and resources). PCPs desired electronic prompts and lab decision support, concise guidelines, and healthcare financing reform to improve CKD care.ConclusionsPCPs face substantial but modifiable barriers in providing care to patients with CKD. Interventions that address these barriers and promote facilitative tools may improve PCPs' effectiveness and capacity to care for patients with CKD
The Virtues of Thisness Presentism
Presentists believe that only present things exist. But opponents insist this view has unacceptable implications: if only present things exist, we canât express singular propositions about the past, since the obvious propositional constituents donât exist, nor can we account for temporal passage, or the openness of the future. According to such opponents, and in spite of the apparent âcommon senseâ status of the view, presentism should be rejected on the basis of these unacceptable implications. In this paper, I present and defend a version of presentism (âThisness Presentismâ) that avoids the unacceptable implications. The basic strategy I employ is familiarâI postulate presently existing entities to serve as surrogates (or âproxiesâ) for non-present entitiesâbut some of the details of my proposal are more novel, and their application to these problems is certainly novel. One overarching thesis of this paper is that Thisness Presentism is preferable to other versions of presentism since it solves important problems facing standard iterations of the view. And I assume that this is a good positive reason in favour of the underlying thisness ontology
- âŠ