Examining the Contributions of Glacial Till Water to Storm Runoff using Two- and Three-Component Hydrograph Separations

Two- and three-component hydrograph separations based on 18O and dissolved silica are used to investigate the contributions of glacial till water to the storm runoff of a headwater stream on the Canadian Shield. Two-component isotopic hydrograph separations based on 18O indicate that the volume and flux of event water could be accounted for by direct precipitation onto saturated areas. Three-component hydrograph separations distinguish between event water, preevent soil water, and preevent till water. These results show that groundwater flow through coarse-textured glacial tills can make a significant contribution to stream discharge during runoff events (29 and 62% in this study) despite the lower hydraulic conductivities of the tills compared to the overlying soils. The three-component hydrograph separations also demonstrate that the relative contributions of preevent soil water and preevent till water changed during one runoff event such that the average water chemistry of the preevent component varied during the event. Two-component hydrograph separations using dissolved silica indicate that seasonal changes in the till water contributions also occur and are related to groundwater levels. Measurements of vertical hydraulic gradients during runoff events indicate that the increase in flow from the tills to the soils is minimal and cannot account for the large and rapid increase in till water flow into the stream. Till water that has discharged to the soils prior to the event is probably being flushed from the soils into the stream during events

Valuing National Forest Recreation Access: Using a Stratified On-Site Sample to Generate Values Across Activities for a Nationally Pooled Sample

The Forest Service controls vast quantities of natural resources including timber, wildlife, watersheds, air sheds, and ecosystems. For many of these resources, recreation is one of the primary uses of the natural asset. Recreation visits taken to National Forests are not "purchased" in the same type of market as other goods (e.g., timber, grazing, or housing). The price of, and ultimately benefit received from, recreation to National Forests cannot be estimated via traditional market prices and quantities. Alternate methods must be employed to estimate the value of recreation access. We use on-site survey data from the Forest Service's National Visitor Use Monitoring database (2000-2003) and stated preference demand estimation methods to model annual recreation trip-taking behavior to National Forests. We then use these models to derive estimates of per-visit net economic benefits across regions and activities. In 2000, the FS began conducting systematic research into recreation visitation levels on National Forest lands under the National Visitor Use Monitoring Project (NVUM). From 2000 to 2003 NVUM has collected data from 120 National Forests providing information on the number of annual visits, primary activity, local area expenditures, satisfaction with facilities, and limited demographic information. These data were collected using an on-site stratified random sampling scheme resulting in over 90,000 completed surveys. Using the NVUM data we estimate the net economic value (NEV) of recreation on National Forest lands. The dataset used to estimate these values contains 73,655 observations. Using a truncated negative binomial estimator, weighted by a composite factor that adjusts for the stratified, on-site nature of the data, we have estimated a series of pooled, multi-site recreation demand models and calculated net economic values for recreational visits to the National Forests for each of fourteen activities and four RPA regions (Pacific, Rocky Mountain, Northern, and Southern) on a per visit per individual value and for a per activity day per individual basis. Our results indicate that for most models and specifications, adjusting for the choice based sampling frame by using a truncated, weighted, stratified, negative binomial estimator, as well as accounting for regional and activity differences, reduces the estimate of the average per day and per activity day values. Forest managers and others involved in managing, planning, and administering resources used for recreation often need an estimate of the economic value of the resource. For many of these resources non-market analysis must be used to generate this information. For forest recreation, many of the values currently available come from secondary sources or from small samples. The values estimated using NVUM represent an improvement over many of the currently available forest recreation values because of the unique nature of the large-scale, stratified random sample.Resource /Energy Economics and Policy,

Accounting for Geographic Heterogeneity in Recreation Demand Models

Spatial differences in site characteristics and user populations may result in heterogeneity of recreation preferences and values across geographic regions. Non-linear mixed effects models provide a potential means of accounting for this heterogeneity. This approach was tested by estimating a national-level recreation demand model with encouraging results.Resource /Energy Economics and Policy,

Ethics in practice: the state of the debate on promoting the social value of global health research in resource poor settings particularly Africa

<p>Abstract</p> <p>Background</p> <p>Promoting the social value of global health research undertaken in resource poor settings has become a key concern in global research ethics. The consideration for benefit sharing, which concerns the elucidation of what if anything, is owed to participants, their communities and host nations that take part in such research, and the obligations of researchers involved, is one of the main strategies used for promoting social value of research. In the last decade however, there has been intense debate within academic bioethics literature seeking to define the benefits, the beneficiaries, and the scope of obligations for providing these benefits. Although this debate may be indicative of willingness at the international level to engage with the responsibilities of researchers involved in global health research, it remains unclear which forms of benefits or beneficiaries should be considered. International and local research ethics guidelines are reviewed here to delineate the guidance they provide.</p> <p>Methods</p> <p>We reviewed documents selected from the international compilation of research ethics guidelines by the Office for Human Research Protections under the US Department of Health and Human Services.</p> <p>Results</p> <p>Access to interventions being researched, the provision of unavailable health care, capacity building for individuals and institutions, support to health care systems and access to medical and public health interventions proven effective, are the commonly recommended forms of benefits. The beneficiaries are volunteers, disease or illness affected communities and the population in general. Interestingly however, there is a divide between "global opinion" and the views of particular countries within resource poor settings as made explicit by differences in emphasis regarding the potential benefits and the beneficiaries.</p> <p>Conclusion</p> <p>Although in theory benefit sharing is widely accepted as one of the means for promoting the social value of international collaborative health research, there is less agreement amongst major guidelines on the specific responsibilities of researchers over what is ethical in promoting the social value of research. Lack of consensus might have practical implications for efforts aimed at enhancing the social value of global health research undertaken in resource poor settings. Further developments in global research ethics require more reflection, paying attention to the practical realities of implementing the ethical principles in real world context.</p

Forms of benefit sharing in global health research undertaken in resource poor settings: a qualitative study of stakeholders' views in Kenya

BACKGROUND: Increase in global health research undertaken in resource poor settings in the last decade though a positive development has raised ethical concerns relating to potential for exploitation. Some of the suggested strategies to address these concerns include calls for providing universal standards of care, reasonable availability of proven interventions and more recently, promoting the overall social value of research especially in clinical research. Promoting the social value of research has been closely associated with providing fair benefits to various stakeholders involved in research. The debate over what constitutes fair benefits; whether those that addresses micro level issues of justice or those focusing on the key determinants of health at the macro level has continued. This debate has however not benefited from empirical work on what stakeholders consider fair benefits. This study explores practical experiences of stakeholders involved in global health research in Kenya, over what benefits are fair within a developing world context. METHODS AND RESULTS: We conducted in-depth interviews with key informants drawn from within the broader health research system in Kenya including researchers from the mainstream health research institutions, networks and universities, teaching hospitals, policy makers, institutional review boards, civil society organisations and community representative groups.The range of benefits articulated by stakeholders addresses both micro and macro level concerns for justice by for instance, seeking to engage with interests of those facilitating research, and the broader systemic issues that make resource poor settings vulnerable to exploitation. We interpret these views to suggest a need for global health research to engage with current crises that face people in these settings as well as the broader systemic issues that produce them. CONCLUSION: Global health research should provide benefits that address both the micro and macro level issues of justice in order to forestall exploitation. Embracing the two is however challenging in terms of how the various competing interests/needs should be balanced ethically, especially in the absence of structures to guide the process. This challenge should point to the need for greater dialogue to facilitate value clarification among stakeholders

Estimating the Net Economic Value of National Forest Recreation: An Application of the National Visitor Use Monitoring Database.

Environmental Economics and Policy, Research Methods/ Statistical Methods, Resource /Energy Economics and Policy,

Geographical Analysis of US Green Sector Industry Concentration

This paper analyzes the geographic distribution of “green energy” sector clustering in the lower 48 United States using recent developments in industry concentration analysis. Evidence suggests that the ten green energy subsectors and the aggregate of the firms comprising the green energy sector are regionally concentrated. Positive changes in industry concentration from 2002 to 2006 tended to be greatest in non-metropolitan counties, suggesting comparative advantage with respect to site location for the composite of firms making up these sectors.Agglomeration, Location Quotient, Renewable Energy, Community/Rural/Urban Development, Industrial Organization, Research and Development/Tech Change/Emerging Technologies,

Estimating Travel Cost Model: Spatial Approach

travel cost model, spatial analysis, Environmental Economics and Policy,

Characterizing Australia's east coast cyclones (1950–2019)

East coast cyclones (ECCs) provide an essential reprieve from dry periods across eastern Australia. They also deliver flood‐producing rains with significant economic, social and environmental impacts. Assessing and comparing the influence of different types of cyclones is hindered by an incomplete understanding of ECC typology, given their widely variable spatial and temporal characteristics. This study employs a track‐clustering method (probabilistic curve‐aligned regression model) to identify key cyclonic pathways for ECCs from 1950 to 2019. Six spatially independent clusters were successfully distinguished and further sub‐classified (coastal, continental and tropical) based on their genesis location. The seasonality and long‐term variability, intensity (maximum Laplacian value ± two days) and event‐based rainfall were then evaluated for each cluster to quantify the impact of these storms on Australia. The highest quantity of land‐based rainfall per event is associated with the tropical cluster (Cluster 6), whereas widespread rainfall was also found to occur in the two continental lows (Cluster 4 and 5). Cyclone tracks orientated close to the coast (clusters 1, 2 and 3) were determined to be the least impactful in terms of rainfall and intensity, despite being the most common cyclone type. In terms of interannual variability, sea surface temperature anomalies suggest an increased cyclone frequency for clusters 1 (austral winter) and 4 (austral spring) during a central Pacific El Niño. Further, cyclone incidence during IOD‐negative conditions was more pronounced in winter for clusters 1, 2, 3 – and clusters 4 and 5 in spring. All cyclones also predominantly occurred in SAM‐positive conditions. However, winter ECCs for clusters 1 and 3 had a higher frequency in SAM‐negative. This new typology of ECCs via spatial clustering provides crucial insights into the systems that produce extreme rainfall across eastern Australia and should be used to inform future hazard management of cyclone events. This article is protected by copyright. All rights reserved

An allometric scaling relationship in the brain of preterm infants

Allometry has been used to demonstrate a power–law scaling relationship in the brain of premature born infants. Forty-nine preterm infants underwent neonatal MRI scans and neurodevelopmental testing at age 2. Measures of cortical surface area and total cerebral volume demonstrated a power–law scaling relationship (α = 1.27). No associations were identified between these measures and investigated clinical variables. Term equivalent cortical surface area and total cerebral volume measures and scaling exponents were not related to outcome. These findings confirm a previously reported allometric scaling relationship in the preterm brain, and suggest that scaling is not a sensitive indicator of aberrant cortical maturation