Using Matching Estimators to Evaluate the Effect of Unit-Based Pricing on Municipal Solid Waste Disposal

The delivery of municipal services for the collection, transfer, and disposal of household solid waste is often provided by local governmental units; typically at the town or city level. Unit-based pricing, also known as pay-as-you-throw (PAYT), is a residential solid waste collection program requiring households to pay a fee per bag of trash disposed. Unit-based pricing represents a significant departure from the historical practice of financing solid waste service from property tax revenues in which the marginal cost to a household for disposing solid waste is effectively zero. Local governments are motivated to adopt unit-based pricing for the purpose of creating a financial incentive for households to reduce the quantity of solid waste disposed and concurrently increasing the level of recycled materials. The objective of this study is to evaluate the impact of unit-based pricing of household solid waste disposal. A counter-factual model is used to estimate the program effect. The study area for this paper consists of the 234 incorporated towns and cities in the state of New Hampshire. As of 2008, 40 towns had adopted a form of unit-based pricing of household solid waste. Results from propensity score matching suggest there is an average annual reduction of 466 pounds of household solid waste due to unit-based pricing.Propensity score matching, unit-based pricing, pay-as-you-throw, municipal solid waste, Environmental Economics and Policy,

A new approach to varietal identification in plants by microsatellite high resolution melting analysis: application to the verification of grapevine and olive cultivars

<p>Abstract</p> <p>Background</p> <p>Microsatellites are popular molecular markers in many plant species due to their stable and highly polymorphic nature. A number of analysis methods have been described but analyses of these markers are typically performed on cumbersome polyacrylamide gels or more conveniently by capillary electrophoresis on automated sequencers. However post-PCR handling steps are still required. High resolution melting can now combine detailed sequence analysis with the closed-tube benefits of real-time PCR and is described here as a novel way to verify the identity of plant varieties such as grapevine and olive.</p> <p>Results</p> <p>DNA melting profiles for various plant variety and rootstock samples were compared to profiles for certified reference samples. Two closely related grapevine rootstocks differing by as little as a single di-nucleotide repeat could be rapidly differentiated while there was high reproducibility of melting profiles for identical cultivars.</p> <p>Conclusion</p> <p>This novel microsatellite analysis method allows high sample throughput with greatly reduced time to results for varietal certification and is amenable to other microsatellite analyses.</p

Evaluation of issues for small and medium-sized enterprises in the use of advanced and green engineering materials

The aim of the research is to identify and evaluate the issues for Small and Medium-sized Enterprise's (SMEs) with the use of Advanced and Green Engineering Materials (AGEMs); determine if the issues are linked to the previous use of an AGEM, or restricting the uptake of AGEMS; and investigate the issues with 5 individual AGEMs. The research identified trends by surveying firms from the construction industry. An online survey tool, Survey Monkey, was used to distribute and collect the survey. From the survey results, the leading issues for: AGEMs in general; AGEMS previously used by SMEs; and AGEMs not previously used by SMEs, was found to be a made up of seven common issues, with the leading issues changing depending on the category examined. The leading seven issues were: 'Experience', 'Cost of Materials', 'Standards or Codes', 'Availability', 'Material Properties', 'Evaluation Methods' and 'Perception'. The assortment of issues tended to depend on whether SMEs had used an AGEM before or not; with intangible issues decreasing and tangible issues increasing with use. Experience appears to be the leading issue to restrict the uptake of AGEMs and should be the first issue Manufacturers consider correcting. Which could reduce the length of awareness time prior to use of AGEMs and decrease a number of other intangible issues. The examination of individual AGEMs agreed with the cumulative picture of issues with AGEMs and would require further research for more in depth analysis

Characterizing Sediment from Riverton, WY

Riverton, Wyoming is home to the seventh-largest Native American Reservation by area and a former uranium processing facility. Milling activities at this site have left the sediments and groundwater with elevated concentrations of uranium that occasionally disrupt water quality to the 12,000 residents of the reservation. The floodplain becomes seasonally wet and sometimes flooded from snowmelt that can be amplified by El Niño events. As a result, the sediments of this area experience periodic droughts and floods. There is concern that a decreased water stage can have major impacts on the geochemical makeup of this ecosystem as 1) a decreased water volume may result in an increase of pollutant concentrations and 2) a decreased water stage can have a significant impact the redox cycling within the subsurface and affect major biogeochemical cycles. This study addresses the need to understand current subsurface elemental distributions in Riverton, Wyoming. Overall, the project explores the sediment characteristics of several Riverton cores in response to drought and flood conditions. Samples for this study were taken over the course of twelve months - at three different time points. This summer, 105 Riverton sediment samples from August 2016 (the final time point) were geochemically characterized and compared to samples from dry conditions (August 2015) prior to the second largest flood on record at this location. We expect the sediments collected prior to the flood to vary greatly from the sediments collected after the flood because the activity of microbial communities is affected by differences in the physical structure of the soil. This data, along with an analysis of the microbial communities present in these sediments, will help the Francis Lab understand what factors shape the distribution and diversity of microbial communities present in order to better understand the subsurface biogeochemistry at Riverton

FIRE Spectroscopy of Five Late-type T Dwarfs Discovered with the Wide-field Infrared Survey Explorer

We present the discovery of five late-type T dwarfs identified with the Wide-field Infrared Survey Explorer (WISE). Low-resolution near-infrared spectroscopy obtained with the Magellan Folded-port InfraRed Echellette (FIRE) reveal strong water and methane absorption in all five sources, and spectral indices and comparison to spectral templates indicate classifications ranging from T5.5 to T8.5:. The spectrum of the latest-type source, WISE J1812+2721, is an excellent match to that of the T8.5 companion brown dwarf Wolf 940B. WISE-based spectrophotometric distance estimates place these T dwarfs at 12-13 pc from the Sun, assuming they are single. Preliminary fits of the spectral data to the atmosphere models of Saumon & Marley indicate effective temperatures ranging from 600 K to 930 K, both cloudy and cloud-free atmospheres, and a broad range of ages and masses. In particular, two sources show evidence of both low surface gravity and cloudy atmospheres, tentatively supporting a trend noted in other young brown dwarfs and exoplanets. In contrast, the high proper motion T dwarf WISE J2018-7423 exhibits a suppressed K-band peak and blue spectrophotometric J-K colors indicative of an old, massive brown dwarf; however, it lacks the broadened Y-band peak seen in metal-poor counterparts. These results illustrate the broad diversity of low-temperature brown dwarfs that will be uncovered with WISE.Comment: 19 pages, 13 figures; accepted for publication to Ap

Ghost Images in Helioseismic Holography? Toy Models in a Uniform Medium

Helioseismic holography is a powerful technique used to probe the solar interior based on estimations of the 3D wavefield. Porter--Bojarski holography, which is a well-established method used in acoustics to recover sources and scatterers in 3D, is also an estimation of the wavefield, and hence it has the potential to be applied to helioseismology. Here we present a proof of concept study, where we compare helioseismic holography and Porter--Bojarski holography under the assumption that the waves propagate in a homogeneous medium. We consider the problem of locating a point source of wave excitation inside a sphere. Under these assumptions, we find that the two imaging methods have the same capability of locating the source, with the exception that helioseismic holography suffers from "ghost images" (i.e., artificial peaks away from the source location). We conclude that Porter--Bojarski holography may improve the current method used in helioseismology.Comment: 17 pages, 8 figure

THE GIS PROFESSIONAL ETHICS PROJECT: PRACTICAL ETHICS EDUCATION FOR GIS PROS

Abstract GIS professors and GIS professionals are separate but overlapping populations, in the U.S. at least. Both communities care about the moral and ethical implications of geospatial technologies and practices. They tend to express their concerns in different ways, however. Over the past 20 years scholars (particularly those affiliated with the discipline of Geography) have contributed critiques of the instrumental nature of GIS as well as reflective case studies that seek to demonstrate how the technology can be used to promote social justice. During the same period a profession of GIS coalesced; by mid-2009 over 4,500 individuals had earned certification as GIS Professionals. Requirements for professional certification in the U.S. include practitioners&apos; commitment to comply with a formal Code of Ethics and Rules of Conduct. Meanwhile, U.S. higher education institutions have rushed to develop practice-oriented certificate and degree programs in response to the increasing demand for qualified GIS professionals in industry and government. Professional programs differ from academic degree programs in that most are designed to produce practitioners rather than scholars. In general, the rich literature in GIS and Society and Critical GIS is more useful to students and instructors in academic programs than those in professional programs. The objective of the National Science Foundation-funded GIS Professional Ethics Project is to produce open educational resources (especially formal case studies with explicit linkages to the Code and Rules) that help professional programs prepare current and future practitioners to recognize ethical problems and to act with integrity. The project (http://gisprofessionalethics.org) combines the perspectives and experience of GIS educators and applied ethicists. The goal of this ICA paper is to promote widespread use of GIS-specific case studies and to invite international perspectives on applied ethics in the GIS profession

A T8.5 Brown Dwarf Member of the Xi Ursae Majoris System

The Wide-field Infrared Survey Explorer has revealed a T8.5 brown dwarf (WISE J111838.70+312537.9) that exhibits common proper motion with a solar-neighborhood (8 pc) quadruple star system - Xi Ursae Majoris. The angular separation is 8.5 arc-min, and the projected physical separation is about 4000 AU. The sub-solar metallicity and low chromospheric activity of Xi UMa A argue that the system has an age of at least 2 Gyr. The infrared luminosity and color of the brown dwarf suggests the mass of this companion ranges between 14 and 38 Jupiter masses for system ages of 2 and 8 Gyr respectively.Comment: AJ in press, 12 pages LaTeX with 6 figures. More astrometric data and a laser guide star adaptive optics image adde