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In 2009, West Virginia enacted an Alternative and Renewable Portfolio Act (APRA) to broaden its energy use for electricity beyond coal. A choice experiment survey was conducted to assess West Virginians’ willingness to pay (WTP) for 10 percent of electricity generated from wind energy versus natural gas. Results showed that residential consumers preferred electricity generated from wind, with annual per-capita WTP averaging from $19.25 to $26.75. Given the subsequent repeal of the APRA in 2015, we propose implementation of a voluntary green pricing program as an alternative policy to increase the share of renewable energy in West Virginia's energy portfolio.
To assess the quality of nutrition content and the integration of user quality components and behaviour change theory relevant to food purchasing behaviour in a sample of existing mobile apps.
Descriptive comparative analysis of eleven mobile apps comprising an assessment of their alignment with existing evidence on nutrition, behaviour change and user quality, and their potential ability to support healthier food purchasing behaviour.
Mobile apps freely available for public use in GoogePlay were assessed and scored according to agreed criteria to assess nutrition content quality and integration of behaviour change theory and user quality components.
A sample of eleven mobile apps that met predefined inclusion criteria to ensure relevance and good quality.
The quality of the nutrition content varied. Improvements to the accuracy and appropriateness of nutrition content are needed to ensure mobile apps support a healthy behaviour change process and are accessible to a wider population. There appears to be a narrow focus towards behaviour change with an overemphasis on behavioural outcomes and a small number of behaviour change techniques, which may limit effectiveness. A significant effort from the user was required to use the mobile apps appropriately which may negatively influence user acceptability and subsequent utilisation.
Existing mobile apps may offer a potentially effective approach to supporting healthier food purchasing behaviour but improvements in mobile app design are required to maximise their potential effectiveness. Engagement of mobile app users and nutrition professionals is recommended to support effective design.
The East African Orogen contains a series of high-strain zones that formed as Gondwana amalgamated. The Tulu Dimtu shear belt is one of these N–S structures within the Barka–Tulu Dimtu zone in western Ethiopia, and contains ultramafic bodies of equivocal origin. Identifying the petrogenetic origin of these enigmatic rocks provides evidence for the geodynamic significance of these shear zones. Owing to their altered state, these ultramafic rocks’ well-preserved chrome spinels provide the only reliable evidence for their source and tectonic affiliation. Chrome spinels have high Cr2O3 (30.04–68.76 wt %), while recalculated Fe2O3 (< 2 %) and TiO2 (0.01–0.51 %) values are low. The Cr# (molar Cr3+/Cr3+ + Al2+) and Mg# (Mg2+/Mg2+ + Fe2+) have averages of 0.88 and 0.22, respectively. Based on olivine–spinel equilibria, the calculated fO2 values (FMQ +3.03) for the dunites reveal a highly oxidized environment. This spinel chemistry (high Cr# > 0.6 and low Ti) supports a supra-subduction origin, with an oxidized mantle source more refractory than depleted MORB mantle (DMM). These spinel compositions indicate that some ultramafic bodies in western Ethiopia, including those from Daleti, Tulu and Dimtu, are serpentinized peridotites emplaced as obducted ophiolite complexes. By contrast, the ultramafic rocks from the Yubdo locality have a different spinel chemistry, with strong affiliation with igneous spinels formed in Alaskan-style mafic intrusions. These collective results suggest that regardless of their origin as supra-subduction ophiolites or as Alaskan-type intrusions, these spinels were formed on a convergent-subduction margin.
The Omani basement is located spatially distant from the dominantly juvenile Arabian–Nubian Shield (ANS) to its west, and its relationship to the amalgamation of those arc terranes has yet to be properly constrained. The Jebel Ja'alan (NE Oman) basement inlier provides an excellent opportunity to better understand the Neoproterozoic tectonic geography of Oman and its relationship to the ANS. To understand the origin of this basement inlier, we present new radiogenic isotopic data from igneous bodies in Jebel Ja'alan. U–Pb and 40Ar/39Ar geochronological data are used to constrain the timing of magmatism and metamorphism in the jebel. Positive εHf and εNd values indicate a juvenile origin for the igneous lithologies. Phase equilibria modelling is used to constrain the metamorphic conditions recorded by basement. Pressure–temperature (P–T) pseudosections show that basement schists followed a clockwise P–T path, reaching peak metamorphic conditions of c. 650–700°C at 4–7.5 kbar, corresponding to a thermal gradient of c. 90–160°C/kbar. From the calculated thermal gradient, in conjunction with collected trace-element data, we interpret that the Jebel Ja'alan basement formed in an arc environment. Geochronological data indicate that this juvenile arc formed during Tonian time and is older than basement further west in Oman. We argue that the difference in timing is related to westwards arc accretion and migration, which implies that the Omani basement represents its own tectonic domain separate to the ANS and may be the leading edge of the Neoproterozoic accretionary margin of India.
The focus of the current study was on the market potential for grass-fed beef in the Appalachian region, given that these products embody observed, experiential, nutritional, and process attributes that may appeal to a large consumer base. An in-store variant of the Becker-DeGroot-Marschack experimental auction mechanism was employed in the region to determine consumer preferences and willingness to pay. A majority of respondents preferred the grass-fed product over conventional grain-fed samples and were willing to pay a price premium to obtain it. Preferences for grass-fed were rooted largely in the associated superior nutritional content and core observed attributes.
A mixed-integer linear programming model was formulated to minimize the cost of transport and processing of excess manure in the Chesapeake Bay watershed. The results showed that primarily poultry manure was moved out of surplus counties for land application or processing. In the base model, annual cost was more than $350 million, with the bulk of the cost arising from construction of energy facilities for poultry manure. Forestland application of poultry manure had the lowest average cost, and more forestland than agricultural land was used for manure application. The lowest cost scenario was $127 million annually when constraints were removed to expand manure application on agricultural land and allow unlimited construction of composting facilities. Such a low-cost solution could not realistically be implemented without further development of markets for compost.
Microbial fuel cells (MFCs) use microorganisms to simultaneously break down organic materials and generate electricity. One of the greatest challenges in the practical application of MFCs is to sufficiently increase their power generation. Nanomodified graphite carbon anodes were prepared for use in MFCs to enhance the electron transport from the microbes to the electrode. Nanomodification to the anodes included growth of nanoparticles and multi-walled carbon nanotubes (MWCNTs). Nanoparticles of various metals, including Au, Ni, Pd, and Fe, were synthesized through thermal annealing and Fe catalyzed MWCNTs were synthesized through chemical vapor deposition. Power density was measured in MFCs for each type of nanomodified electrodes. Significant increase in power density was observed for the MFC with anodes decorated with MWCNTs (with 50-100nm diameters).
When using a willingness-to-pay (WTP) format in contingent valuation (CV) to value watershed restoration, respondents may protest by questioning why they should pay to clean up a pollution problem that someone else created. Using a sample selection interval data model based on Bhat (1994) and Brox, Kumar, and Stollery (2003), we found that the decision to protest and WTP values were correlated. Protest sample selection bias resulted in a 300 percent overestimate of mean WTP per respondent. Using different ad hoc treatments of protesters, protest bias resulted in moderate effects (−10 percent to +14 percent) after controlling for sample selection bias.
While historians believe that preserving a historic building in its original location is important to maintain its historic integrity, the general public's opinion is unknown. Survey data were gathered from local residents regarding a proposed relocation of a historic mill in rural West Virginia. Only a minority of the sample population supported preserving the mill at its original location. Willingness to pay for preservation was estimated at $8.45 for a one-time donation for the sample and $2.29 after adjusting for non-respondents using characteristics of the local population.