A Utility-Theoretic Approach to Measuring Changes in US Rural Residents' Access to Hospital Services from 1980 to 1999

Questions of access to hospital services figure centrally in rural-health policy debates, yet few analyses exist that measure the importance of changes in hospital access in rural areas of the US. Of the studies that measure changes in access to hospital services over time in the literature, none use economic theory as the framework for the analysis. This paper proposes an economic approach based upon revealed preferences to measuring access to hospital services and quantifies the value of changes in hospital access over the period 1980 to 1999 for residents in rural counties in the US. Welfare measures are constructed for the years 1980 and 1999 for rural residents in all the rural counties of the US. On average the lowest levels of hospital access are found in the counties of the West, while Eastern US counties have better access to hospitals in comparison. The changes in hospital-consumer welfare indicate that over the period 1980 to 1999, access to hospital services has declined for rural US residents.Health Economics and Policy,

Active galactic nucleus feedback in clusters of galaxies

Observations made during the last ten years with the Chandra X-ray Observatory have shed much light on the cooling gas in the centers of clusters of galaxies and the role of active galactic nucleus (AGN) heating. Cooling of the hot intracluster medium in cluster centers can feed the supermassive black holes found in the nuclei of the dominant cluster galaxies leading to AGN outbursts which can reheat the gas, suppressing cooling and large amounts of star formation. AGN heating can come in the form of shocks, buoyantly rising bubbles that have been inflated by radio lobes, and the dissipation of sound waves.Comment: Refereed review article published in Chandra's First Decade of Discovery Special Feature edition of the Proceedings of the National Academy of Science

Quantifying the influence of sea ice on ocean microseism using observations from the Bering Sea, Alaska

Microseism is potentially affected by all processes that alter ocean wave heights. Because strong sea ice prevents large ocean waves from forming, sea ice can therefore significantly affect microseism amplitudes. Here we show that this link between sea ice and microseism is not only a robust one but can be quantified. In particular, we show that 75–90% of the variability in microseism power in the Bering Sea can be predicted using a fairly crude model of microseism damping by sea ice. The success of this simple parameterization suggests that an even stronger link can be established between the mechanical strength of sea ice and microseism power, and that microseism can eventually be used to monitor the strength of sea ice, a quantity that is not as easily observed through other means

The Impact of Triclosan on the Spread of Antibiotic Resistance in the Environment

Triclosan (TCS) is a commonly used antimicrobial agent that enters wastewater treatment plants (WWTPs) and the environment. An estimated 1.1 × 105 to 4.2 × 105 kg of TCS are discharged from these WWTPs per year in the United States. The abundance of TCS along with its antimicrobial properties have given rise to concern regarding its impact on antibiotic resistance in the environment. The objective of this review is to assess the state of knowledge regarding the impact of TCS on multidrug resistance in environmental settings, including engineered environments such as anaerobic digesters. Pure culture studies are reviewed in this paper to gain insight into the substantially smaller body of research surrounding the impacts of TCS on environmental microbial communities. Pure culture studies, mainly on pathogenic strains of bacteria, demonstrate that TCS is often associated with multidrug resistance. Research is lacking to quantify the current impacts of TCS discharge to the environment, but it is known that resistance to TCS and multidrug resistance can increase in environmental microbial communities exposed to TCS. Research plans are proposed to quantitatively define the conditions under which TCS selects for multidrug resistance in the environment

Current Status of Lay Share Wage Claims in Admiralty Law

This Article explores the parameters of claims under oral lay share agreements in the commercial fishing industry. The Article analyzes such agreements by exploring the rationale used in the four principal lay share cases in the geographic area of the U.S. Court of Appeals for the Ninth Circuit. Additionally, this Article considers the historical development of, and policies behind, maritime laws favoring able seamen, and how these laws have contributed to oral lay share agreements as those agreements affect the rights of commercial fishermen

Hot Atmospheres, Cold Gas, AGN Feedback and the Evolution of Early Type Galaxies: a Topical Perspective

Most galaxies comparable to or larger than the mass of the Milky Way host hot, X-ray emitting atmospheres, and many such galaxies are radio sources. Hot atmospheres and radio jets and lobes are the ingredients of radio-mechanical active galactic nucleus (AGN) feedback. While a consensus has emerged that such feedback suppresses cooling of hot cluster atmospheres, less attention has been paid to massive galaxies where similar mechanisms are at play. Observation indicates that the atmospheres of elliptical and S0 galaxies were accreted externally during the process of galaxy assembly and augmented significantly by stellar mass loss. Their atmospheres have entropy and cooling time profiles that are remarkably similar to those of central cluster galaxies. About half display filamentary or disky nebulae of cool and cold gas, much of which has likely cooled from the hot atmospheres. We review the observational and theoretical perspectives on thermal instabilities in galactic atmospheres and the evidence that AGN heating is able to roughly balance the atmospheric cooling. Such heating and cooling may be regulating star formation in all massive spheroids at late times.Comment: Final versio

Effects of Impulsivity and Self-control on Calorie Intake

Neoclassical economic theory models individuals as making consistent choices over time and it assumes these choices are the outcome of rational utility maximization. Recent theoretical developments in the theory of consumer decision-making have drawn evidence from other disciplines such as, neuroscience (McClure et al, 2004) and psychology, and proposed more generalized models in a dual-self framework explicitly accounting for self-control or impulsivity (Gul and Pesendorfer, 2004; Fudenberg and Levine, 2006; and Brocas and Carillo, 2008). This study attempts to understand the dietary choices in a dual-self framework while explicitly identifying calorie intake owing to impulsivity and self-control. We construct standard psychological measures using the responses to the Dutch Eating Behavioral Questionnaire (DEBQ) filled by the respondents of the UK Diet and Nutrition Survey. These measures have been tested for their validity and apply to a broad range of population: of different weights, across gender, ethnicity (Bardone-Cone, and Boyd, 2007) and are used in experiments (Ouwens, 2005).Using panel data methods, we find that impulsivity increases calorie intake and self-control decreases calorie intake. Further, caloric intake is larger than one can restrain and therefore the result of the intrapersonal conflict is positive calories intake on average.Self-control, Nutrition, diet, health, impulsivity, BMI, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety, Health Economics and Policy, Institutional and Behavioral Economics, D12, D03, I00,

The M\"obius function of generalized subword order

Let P be a poset and let P* be the set of all finite length words over P. Generalized subword order is the partial order on P* obtained by letting u \leq w if and only if there is a subword u' of w having the same length as u such that each element of u is less than or equal to the corresponding element of u' in the partial order on P. Classical subword order arises when P is an antichain, while letting P be a chain gives an order on compositions. For any finite poset P, we give a simple formula for the Mobius function of P* in terms of the Mobius function of P. This permits us to rederive in a easy and uniform manner previous results of Bjorner, Sagan and Vatter, and Tomie. We are also able to determine the homotopy type of all intervals in P* for any finite P of rank at most 1.Comment: 29 pages, 4 figures. Incorporates referees' suggestions; to appear in Advances in Mathematic

Mechanical Feedback from Active Galactic Nuclei in Galaxies, Groups, and Clusters

The radiative cooling timescales at the centers of hot atmospheres surrounding elliptical galaxies, groups, and clusters are much shorter than their ages. Therefore, hot atmospheres are expected to cool and to form stars. Cold gas and star formation are observed in central cluster galaxies but at levels below those expected from an unimpeded cooling flow. X-ray observations have shown that wholesale cooling is being offset by mechanical heating from radio active galactic nuclei. Feedback is widely considered to be an important and perhaps unavoidable consequence of the evolution of galaxies and supermassive black holes. We show that cooling X-ray atmospheres and the ensuing star formation and nuclear activity are probably coupled to a self-regulated feedback loop. While the energetics are now reasonably well understood, other aspects of feedback are not. We highlight the problems of atmospheric heating and transport processes, accretion, and nuclear activity, and we discuss the potential role of black hole spin. We discuss X-ray imagery showing that the chemical elements produced by central galaxies are being dispersed on large scales by outflows launched from the vicinity of supermassive black holes. Finally, we comment on the growing evidence for mechanical heating of distant cluster atmospheres by radio jets and its potential consequences for the excess entropy in hot halos and a possible decline in the number of distant cooling flows.Comment: Accepted for publication in New Journal of Physics Focus Issue on Clusters of Galaxie