7,581 research outputs found
Health Risks From Mercury-Contaminated Fish: A Reassessment
Several Congressional bills and a pending EPA regulation would significantly cut mercury emissions from power plants, so as to reduce mercury-related neurological effects among children. There is, however, no estimate of the number of cases of neurological deficiencies that might be avoided by such emissions cuts. To inform policymakers, we develop estimates of the annual number of cases of neurodevelopmental effects among children in the United States, based on existing estimates of the exposure and dose-response relationships for prenatal exposure to methylmercury. Using data on emissions and deposition, we show that eliminating mercury emissions from U.S. power plants would prevent on the order of 10,000 cases of subtle neurological deficiencies per year. For a related paper, see Regulating Mercury Emissions: What Do We Know About Costs and Benefits?Environment, Health and Safety, Regulatory Reform
Litigating Lead-Based Paint Hazards: Is It a Solution?
None.Environment, Health and Safety, Regulatory Reform
Analysis of sorbents and catalysts used during a 90-day manned test
Chemical analysis of organic trace contaminants in simulated space station atmospheres desorbed from molecular sieve, silicon gel, and catalyst bed
Timed Analysis of Security Protocols
We propose a method for engineering security protocols that are aware of
timing aspects. We study a simplified version of the well-known Needham
Schroeder protocol and the complete Yahalom protocol, where timing information
allows the study of different attack scenarios. We model check the protocols
using UPPAAL. Further, a taxonomy is obtained by studying and categorising
protocols from the well known Clark Jacob library and the Security Protocol
Open Repository (SPORE) library. Finally, we present some new challenges and
threats that arise when considering time in the analysis, by providing a novel
protocol that uses time challenges and exposing a timing attack over an
implementation of an existing security protocol
Optical Photometry and Spectroscopy of the Suspected Cool Algol AV Delphini: Determination of the Physical Properties
We present new spectroscopic and BVRI photometric observations of the double-lined eclipsing binary AV Del ( period = 3:85 days) conducted over six observing seasons. A detailed radial velocity and light-curve analysis of the optical data shows the system to be most likely semidetached, with the less massive and cooler star filling its Roche lobe. The system is probably a member of the rare class of ââcool Algolââ systems, which are distinguished from the ââclassicalââ Algol systems in that the mass-gaining component is also a late-type star rather than a B- or A-type star. By combining the spectroscopic and photometric analyses, we derive accurate absolute masses for the components of M1 = 1.453 + 0.028 M and M2 = 0.705 + 0.014 M and radii of R1 = 2.632 + 0.030 R and R2 = 4.233 + 0.060 R, as well as effective temperatures of 6000 + 200 and 4275 + 150 K for the primary and secondary, respectively. There are no obvious signs of activity (spottedness) in the optical light curve of the binary
Regulating Mercury Emissions: What Do We Know About Costs and Benefits?
United States policymakers are concerned with mercury emissions because mercury has potentially adverse effects on children whose mothers consumed contaminated fish while pregnant. Congress and the Environmental Protection Agency are considering different proposals to cut or even eliminate mercury emissions from oil and coal-fired power plants. We compare the cost of cutting power plants' mercury emissions with the likely reductions in the number of cases of subtle neurological effects. Given current scientific understanding, the health and environmental improvements are very unlikely to provide an economic justification for the costs of stringent controls on mercury emissions. In addition, if Congress or EPA were to regulate mercury emissions from power plants, an approach that used prices would be more efficient than one that limited the quantity of mercury emissions. For a related paper, see Health Risks From Mercury-Contaminated Fish: A Reassessment.
Winning Cores in Parity Games
We introduce the novel notion of winning cores in parity games and develop a
deterministic polynomial-time under-approximation algorithm for solving parity
games based on winning core approximation. Underlying this algorithm are a
number properties about winning cores which are interesting in their own right.
In particular, we show that the winning core and the winning region for a
player in a parity game are equivalently empty. Moreover, the winning core
contains all fatal attractors but is not necessarily a dominion itself.
Experimental results are very positive both with respect to quality of
approximation and running time. It outperforms existing state-of-the-art
algorithms significantly on most benchmarks
An Examination of Selected Ethnic Foodways in the Upper Midwest
Many geographers recognize regional studies as a guidepost of geography. Cultural geographers have long identified the significance of ethnic regions and the differences between various ethnic groups in matters of housing, work, agriculture and diet. In many cases foodways and regional cuisine are distinct enough to act as a key identifier of a cultural region. This thesis uses church and other local cookbooks to identify specific ethnic and non - ethnic foods eaten by the Dutch of Northwestern Iowa, the Norwegians of the North Dakota-Minnesota border area, and the German-Russians of Southern North Dakota. From this source of information, patterns of food use offer insight into diffusion and persistence of these folk cultures
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