17,065 research outputs found
Four new Aphodius Illiger from pocket gopher burrows in Arizona, Utah, Kansas and Nebraska (Coleoptera: Scarabaeidae: Aphodiinae)
We describe four new species of winter-active Aphodius (sensu lato) from pocket gopher burrows in Arizona, Utah, Kansas, and Nebraska: A. cacabatus, A. paulseni, A. skillmani, and A. utopensis. Diagnostic characters of all four species are illustrated
Food Risks and Type I & II Errors
The IFAMR is published by (IFAMA) the International Food and Agribusiness Management Review. www.ifama.orgFood safety, food defense, error based disruption, control oriented supply networks, Agribusiness, Food Consumption/Nutrition/Food Safety, Food Security and Poverty, Risk and Uncertainty, Q130,
Zero temperature black holes in semiclassical gravity
The semiclassical Einstein equations are solved to first order in for the case of an extreme or nearly extreme Reissner-Nordstr\"{o}m
black hole perturbed by the vacuum stress-energy of quantized free fields. It
is shown that, for realistic fields of spin 0, 1/2, or 1, any zero temperature
black hole solution to the equations must have an event horizon at ,
with the charge of the black hole. It is further shown that no black hole
solutions with can be obtained by solving the semiclassical
Einstein equations perturbatively.Comment: 7 pages, to appear in the Proceedings of the Ninth Marcel Grossmann
Meeting, change in titl
Inside the Economist's Mind: The History of Modern Economic Thought, as Explained by Those Who Produced It
This is the front matter from a book of interviews to be published by Blackwell. The book is coedited by W. A. Barnett and P. A. Samuelson. The front matter includes the Table of Contents, Coeditor Preface by W. A. Barnett, Coeditor Foreword by Paul A. Samuelson, and History of Thought Introduction by E. Roy Weintraub. The front matter highlights some of the more startling and controversial statements contained in the interviews and puts the interviews into context relative to the history of modern economic thought. The interviews reprinted in this book include: (1) Wassily Leontief interviewed by Duncan Foley. (2) David Cass interviewed jointly by Steven Spear and Randall Wright. (3) Robert E. Lucas interviewed by Bennett T. McCallum. (4) Janos Kornai interviewed by Olivier Blanchard. (5) Franco Modigliani interviewed by William Barnett and Robert Solow. (6) Milton Friedman interviewed by John Taylor. (7) Paul A. Samuelson interviewed by William A. Barnett. (8) Paul Volcker interviewed by Perry Mehrling. (9) Martin Feldstein interviewed by James Poterba. (10) Christopher Sims interviewed by Lars Peter Hansen. (11) Robert Shiller interviewed by John Campbell. (12) Stanley Fischer interviewed by Olivier Blanchard. (13) Jacques Drèze interviewed by Pierre Dehez and Omar Licandro. (14) Tom Sargent interviewed by George Evans and Seppo Honkapohja. (15) Robert Aumann interviewed by Sergiu Hart. (16) James Tobin and Robert Shiller interviewed by David Colander.history of economic thought, Samuelson, macroeconomics, microeconomics, policy, interviews
H-alpha Activity of Old M Dwarfs: Stellar Cycles and Mean Activity Levels For 93 Low-Mass Stars in the Solar Neighborhood
Through the McDonald Observatory M Dwarf Planet Search, we have acquired
nearly 3,000 high-resolution spectra of 93 late-type (K5-M5) stars over more
than a decade using HET/HRS. This sample provides a unique opportunity to
investigate the occurrence of long-term stellar activity cycles for low-mass
stars. In this paper, we examine the stellar activity of our targets as
reflected in the H-alpha feature. We have identified periodic signals for 6
stars, with periods ranging from days to more than 10 years, and find long-term
trends for 7 others. Stellar cycles with P > 1 year are present for at least 5%
of our targets. Additionally, we present an analysis of the time-averaged
activity levels of our sample, and search for correlations with other stellar
properties. In particular, we find that more massive, earlier type (M0-M2)
stars tend to be more active than later type dwarfs. Furthermore,
high-metallicity stars tend to be more active at a given stellar mass. We also
evaluate H-alpha variability as a tracer of activity-induced radial velocity
(RV) variation. For the M dwarf GJ 1170, H-alpha variation reveals stellar
activity patterns matching those seen in the RVs, mimicking the signal of a
giant planet, and we find evidence that the previously identified stellar
activity cycle of GJ 581 may be responsible for the recently retracted planet f
(Vogt et al. 2012) in that system. In general, though, we find that H-alpha is
not frequently correlated with RV at the precision (typically 6-7 m/s) of our
measurements.Comment: Submitted to ApJ. Reflects comments from a positive refere
Composite Flexible Blanket Insulation
Composite flexible multilayer insulation systems (MLI) were evaluated for thermal performance and compared with the currently used fibrous silica (baseline) insulation system. The systems described are multilayer insulations consisting of alternating layers of metal foil and scrim ceramic cloth or vacuum metallized polymeric films quilted together using ceramic thread. A silicon carbide thread for use in the quilting and the method of making it are also described. These systems are useful in providing lightweight insulation for a variety of uses, particularly on the surface of aerospace vehicles subject to very high temperatures during flight
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Beach impact study, Padre Island National Seashore
Prepared for Office of Natural Science, Southwest Region, National Park Service, under contract CX70005044830 April 1976Vegetative differences between heavily and very lightly trafficked beaches show that more beach traffic correlates with quantitative decreases in variety and density of plants and with declines of grasses relative to forbs. The vegetated portions of all beaches continue to grow in volume. However, this is at the expense of the more seaward (more trafficked) parts of the beaches and has lead to overall loss of total beach volume except where vehicular traffic is prohibited. The very lightly trafficked beach is the only study site wherein the entire beach to mean sea level has grown. The effect of these trends on resistance to storm surge erosion remains to be tested.Marine Scienc
Traceability in Food Systems: An Economic Analysis of LGMA and the 2006 Spinach Outbreak
This case study presents an in-depth review of network structures and costs associated with the implementation of traceability systems in California leafy green production, distribution, and retailing. The 2006 spinach outbreak is used to assess the economic impact of trace back/forward response time of the LGMA system, an example of a tightly coupled, linear supply network. Results suggest that the benefits of traceability systems may far outweigh the costs and that costs vary significantly by technology used and by grower size. Implications are derived for cost-effectiveness of rapid response, targeted trace back/forward systems in other types of supply networks.traceability, produce, supply networks, cost-effectiveness, Food Consumption/Nutrition/Food Safety, Production Economics, Q18, I18, L51,
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