Viking planetary quarantine procedures and implementation

Some of the techniques and methodology that were used on Viking to implement planetary quarantine requirements are reported. Special attention was given to techniques and approaches used to implement sterilization of the Viking probe. Quarantine procedures for unmanned planetary missions and procedures for microbiological contamination of space hardware are included. A probability of contamination of the biological instruments onboard by terrestrial organisms was examined

Do Surges in Less-Skilled Immigration Have Important Wage Effects? A Review of the U.S. Evidence

This paper reviews a small part of a vast professional literature on the labor market effects of new immigrants. It focuses on recent studies that have employed econometric techniques to estimate wage effects of less-skilled immigrants during the two great American immigration surges (roughly 1870-1914 and 1980 to the present). � The literature is fairly consistent in finding that large long-term immigrant surges have at least small negative wage effects for less-advantaged members of the labor force, and that these are likely to be largest for foreign-born workers and less-educated African-Americans in major immigrant-receiving regions. While this is consistent with the simple textbook prediction in a largely deregulated labor market, we might have expected more robust negative effects. The explanation may be that these effects are inherently difficult to isolate, especially given the quality of the data. Many less-skilled new immigrants are undocumented workers who are employed by individuals or small family businesses under-the-table and are either not counted or counted poorly. � The paper concludes that, while all consumers and many employers (both as households and as firms) have undoubtedly benefited substantially from the surge in undocumented low-skilled workers since the early 1980s, there are also some losers, and there is consequently a need for policy interventions designed to ensure that socially-acceptable wage levels, employment opportunities, and working conditions are maintained for our least advantaged workers, native- and foreign-born alike.�� David Howell is�a professor at Milano The New School for Management & Urban Policy. He is the editor of Fighting Unemployment: The Limits of Free Market Orthodoxy.immigration, wages, labor markets, labor supply

Device for directionally controlling electromagnetic radiation Patent

Concentrator device for controlling direction of solar energy onto energy converter

Directional control of radiant heat

Surface with grooves having flat bases gives directional emissivities and absorptivities that can be made to approximate a perfect directional surface. Radiant energy can then be transferred in desired directions

Hydrogen production econometric studies

The current assessments of fossil fuel resources in the United States were examined, and predictions of the maximum and minimum lifetimes of recoverable resources according to these assessments are presented. In addition, current rates of production in quads/year for the fossil fuels were determined from the literature. Where possible, costs of energy, location of reserves, and remaining time before these reserves are exhausted are given. Limitations that appear to hinder complete development of each energy source are outlined

By What Measure? A Comparison of French and U.S. Labor Market Performance with New Indicators of Employment Adequacy

The unemployment rate is conventionally relied upon to measure national employment performance, and has been the main indicator justifying comprehensive labor market reforms, generally in the direction of deregulation and benefit reduction. The starting point of this working paper is that a well-functioning labor market should produce not just enough jobs, but enough “decent” jobs. We compare U.S. and French performance according to three indicators, calculated from each country’s main household survey for 1993-2005 by age, gender and education group. With low wages defined as less than 2/3 of the full-time median and inadequate hours defined as working involuntarily part-time, we calculate: 1) the low-wage share of employment; 2) the underemployed share of the labor force; and 3) the adequately employed share of the working age population. France performs well above the U.S. on all three indicators, particularly for less-educated workers, and the French advantage has grown substantially since the late 1990s. In 2005 the underemployed share of the male labor force with less than a high school degree was 64% in the U.S. and just 23% in France; for the female labor force, these figures were 84% in the U.S. and 41% in France. The adequately employed share of the prime-age (25-54) population with just a high school degree was 64% for U.S. men and 80% for French men; among women, these rates were 39% for the U.S. and 63% for France. These results indicate that accounting for adequate pay and hours of work has large effects on the measurement of labor market performance. The authors conclude by recommending that indicators such as these, and not just the unemployment rate, should have a central place in discussions of national labor market reform.This paper was revised in November 2008.labor supply, labor demand, wages, unemployment,

An improved method for estimating source densities using the temporal distribution of Cosmological Transients

It has been shown that the observed temporal distribution of transient events in the cosmos can be used to constrain their rate density. Here we show that the peak flux--observation time relation takes the form of a power law that is invariant to the luminosity distribution of the sources, and that the method can be greatly improved by invoking time reversal invariance and the temporal cosmological principle. We demonstrate how the method can be used to constrain distributions of transient events, by applying it to Swift gamma-ray burst data and show that the peak flux--observation time relation is in good agreement with recent estimates of source parameters. We additionally show that the intrinsic time dependence allows the method to be used as a predictive tool. Within the next year of Swift observation, we find a 50% chance of obtaining a peak flux greater than that of GRB 060017 -- the highest Swift peak flux to date -- and the same probability of detecting a burst with peak flux > 100 photons s^{-1} cm^{-2} within 6 years.Comment: Submitted to ApJ Letter

The effects of bilingualism on speakers who stutter during late childhood

Objectives: To examine stuttering by children speaking an alternative language exclusively (LE) or with English (BIL) and to study onset of stuttering, school performance and recovery rate relative to monolingual speakers who stutter (MONO). Design: Clinical referral sample with supplementary data obtained from speech recordings and interviews. Setting: South-East England, 1999–2007. Participants: Children aged 8–12 plus who stuttered (monolingual and bilingual) and fluent bilingual controls (FB). Main outcome measures: Participants’ stuttering history, SATS scores, measures of recovery or persistence of stuttering. Results: 69 (21.8%) of 317 children were bilingual. Of 38 children who used a language other than English at home, 36 (94.7%) stuttered in both languages. Fewer LE (15/38, 39.5%) than BIL (23/38, 60.5%) children stuttered at first referral to clinic, but more children in the fluent control sample were LE (28/38, 73.7%) than BIL (10/38, 26.3%). The association between stuttering and bilingual group (LE/BIL) was significant by x2 test; BIL speakers have more chance of stuttering than LE speakers. Age at stuttering onset and male/female ratio for LE, BIL and MONO speakers were similar (4 years 9 months, 4 years 10 months and 4 years 3 months, and 4.1:1, 4.75:1 and 4.43:1, respectively). Educational achievement was not affected by bilingualism relative to the MONO and FB groups. The recovery rate for the LE and MONO controls together (55%) was significantly higher by x2 test than for the BIL group (25%). Conclusions: BIL children had an increased risk of stuttering and a lower chance of recovery from stuttering than LE and MONO speakers

Using temporal distributions of transient events to characterize cosmological source populations

The brightest events in a time series of cosmological transients obey an observation time dependence which is often overlooked. This dependence can be exploited to probe the global properties of electromagnetic and gravitational wave transients (Howell et al. 2007a, Coward & Burman 2005). We describe a new relation based on a peak flux--observation time distribution and show that it is invariant to the luminosity distribution of the sources (Howell et al. 2007b). Applying this relation, in combination with a new data analysis filter, to \emph{Swift} gamma-ray burst data, we demonstrate that it can constrain their rate density.Comment: published in proceedings of FRONTIERS OF FUNDAMENTAL AND COMPUTATIONAL PHYSICS: 10th International Symposium, AIP,1246,203, (2010