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Trade Promotion Authority (TPA): Frequently Asked Questions
Trade Promotion Authority (TPA), formerly called fast track, is the authority Congress has granted to the President for limited periods of time to negotiate reciprocal trade agreements. The authority lays out U.S. trade negotiating objectives, procedures for congressional-executive notification and consultation, and expedited legislative procedures under which bills implementing trade agreements negotiated by the executive branch are to be considered. The most recent authority was enacted in December 2002 and expired as of July 1, 2007. Legislation to reauthorize TPA has been introduced in the 113th Congress. The United States is engaged in several sets of trade agreement negotiations. The issue of TPA reauthorization has raised a number of questions regarding TPA itself and the pending legislation. This report addresses a number of those questions that are frequently asked, including:
• What is trade promotion authority?
• Is TPA necessary?
• What are trade negotiating objectives and how are they reflected in TPA statutes?
• What requirements does Congress impose on the President under TPA?
• Does TPA affect congressional authority on trade policy
Identifying genetic variation affecting a complex trait in simulated data: a comparison of meta-analysis with pooled data analysis
We explored the power and consistency to detect linkage and association with meta-analysis and pooled data analysis using Genetic Analysis Workshop 14 simulated data. The first 10 replicates from Aipotu population were used. Significant linkage and association was found at all 4 regions containing the major loci for Kofendrerd Personality Disorder (KPD) using both combined analyses although no significant linkage and association was found at all these regions in a single replicate. The linkage results from both analyses are consistent in terms of the significance level of linkage test and the estimate of locus location. After correction for multiple-testing, significant associations were detected for the same 8 single-nucleotide polymorphisms (SNP) in both analyses. There were another 2 SNPs for which significant associations with KPD were found only by pooled data analysis. Our study showed that, under homogeneous condition, the results from meta-analysis and pooled data analysis are similar in both linkage and association studies and the loss of power is limited using meta-analysis. Thus, meta-analysis can provide an overall evaluation of linkage and association when the original raw data is not available for combining
Galactic accretion and the outer structure of galaxies in the CDM model
We have combined the semi-analytic galaxy formation model of Guo et al.
(2011) with the particle-tagging technique of Cooper et al. (2010) to predict
galaxy surface brightness profiles in a representative sample of ~1900 massive
dark matter haloes (10^12--10^14 M_sol) from the Millennium II Lambda-CDM
N-body simulation. Here we present our method and basic results focusing on the
outer regions of galaxies, consisting of stars accreted in mergers. These
simulations cover scales from the stellar haloes of Milky Way-like galaxies to
the 'cD envelopes' of groups and clusters, and resolve low surface brightness
substructure such as tidal streams. We find that the surface density of
accreted stellar mass around the central galaxies of dark matter haloes is well
described by a Sersic profile, the radial scale and amplitude of which vary
systematically with halo mass (M_200). The total stellar mass surface density
profile breaks at the radius where accreted stars start to dominate over stars
formed in the galaxy itself. This break disappears with increasing M_200
because accreted stars contribute more of the total mass of galaxies, and is
less distinct when the same galaxies are averaged in bins of stellar mass,
because of scatter in the relation between M_star and M_200. To test our model
we have derived average stellar mass surface density profiles for massive
galaxies at z~0.08 by stacking SDSS images. Our model agrees well with these
stacked profiles and with other data from the literature, and makes predictions
that can be more rigorously tested by future surveys that extend the analysis
of the outer structure of galaxies to fainter isophotes. We conclude that it is
likely that the outer structure of the spheroidal components of galaxies is
largely determined by collisionless merging during their hierarchical assemblyComment: Accepted by MNRAS. Shortened following referee's report, conclusions
unchanged. 21 pages, 15 figure
Modeling technique for optimal recovery of immiscible light hydrocarbons as free product from contaminated aquifer
Contamination sites associated with light non-aqueous phase liquids {LNAPL) are numerous and represent difficult cleanup problems. Remediation methods for cleanup of LNAPL fluids in subsurface systems are continuously evolving with the development of various technologies for pump.-and~treat, soil venting, and in-situ bioremediation. Evaluating the effectiveness of remediation techniques as well as attempting to improve their efficiency has been a focus of many researchers, These efforts have included the development of computer simulation models to predict and analyze the fluid movement, entrapment, and mobilization of three~phase systems in porous media. The capability of computer models that not only simulate but optimize remediation processes are in great need. Simulation/optimization (S/0) models allow engineers to optimize processes and to make cost-effective design and management decisions when evaluating remediation strategies. An innovative approach is presented to optimize pumping to immobilize and recover the free product of a floating contaminant consisting of LNAPL\u27s. This determines the best pumping strategy to capture and remove the free oil product not left behind as residual oil. The approach combines detailed simulation, statistical analysis, and operations research optimization. This modeling technique derives regression equations describing system response to unit pumping stimuli. The statistical approach develops regression equations that represent free oil area within the system versus pumping. These equations are derived for multiple time steps and used in the S/0 model to determine the optimized pumping rates required to minimize free oil area and entrapped oil while maximizing free oil recovery and immobilizing the plume via a pump and oil recovery system. When compared with standard simulation techniques, this approach can save substantial computational time and improve remediation strategy design. Utilized is a modified version of US/REMAX, a linear or nonlinear simulation/optimization (S/0) model. US/REMAX can be used to analyze and optimize a variety of groundwater management problems. The modified version incorporates system responses generated externally using ARMOS plus regression analysis. ARMOS is a Z~D areal multiphase flow model. It has the capability of simulating spill, leakage, redistribution, or recovery of LNAPL materials. Application to a representative field problem illustrates the S/O model utility for problem analysis and remediation design. Potential applications of such an S/0 model are numerous providing optimized strategies for recovery of LNAPL spills
Flight Calibration of four airspeed systems on a swept-wing airplane at Mach numbers up to 1.04 by the NACA radar-phototheodolite method
The calibrations of four airspeed systems installed in a North American F-86A airplane have been determined in flight at Mach numbers up to 1.04 by the NACA radar-phototheodolite method. The variation of the static-pressure error per unit indicated impact pressure is presented for three systems typical of those currently in use in flight research, a nose boom and two different wing-tip booms, and for the standard service system installed in the airplane. A limited amount of information on the effect of airplane normal-force coefficient on the static-pressure error is included. The results are compared with available theory and with results from wind-tunnel tests of the airspeed heads alone. Of the systems investigated, a nose-boom installation was found to be most suitable for research use at transonic and low supersonic speeds because it provided the greatest sensitivity of the indicated Mach number to a unit change in true Mach number at very high subsonic speeds, and because it was least sensitive to changes in airplane normal-force coefficient. The static-pressure error of the nose-boom system was small and constant above a Mach number of 1.03 after passage of the fuselage bow shock wave over the airspeed head
Advanced sensors technology survey
This project assesses the state-of-the-art in advanced or 'smart' sensors technology for NASA Life Sciences research applications with an emphasis on those sensors with potential applications on the space station freedom (SSF). The objectives are: (1) to conduct literature reviews on relevant advanced sensor technology; (2) to interview various scientists and engineers in industry, academia, and government who are knowledgeable on this topic; (3) to provide viewpoints and opinions regarding the potential applications of this technology on the SSF; and (4) to provide summary charts of relevant technologies and centers where these technologies are being developed
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