Quiet propulsive lift for commuter airlines

The performance of STOL or RTOL aircraft and NASA's research program to provide options for future design and certification of quiet propulsive-life transports is described

Monetarist Interpretations of the Great Depression: An Evaluation and Critique

This paper rejects the proposition that there is only a single interesting question to ask about the decade of the 1930s. It is concerned not only with the role of money in the 1929-33 contraction but also with the relative role of monetary and nonmonetary factors in the recession of 1937-38 and subsequent recovery and, in addition, with the division of nominal income change between prices and real output. New empirical evidence bearing on each of these issues is provided The results suggest that both extreme monetarist and nonmonetarist interpretations of the decade of the l930s are unsatisfactory and leave interesting features of the data unexplained. Arguing against acceptance of an extreme monetarist interpretation are (1) the inability of changes in the money supply alone to explain the severity of the initial collapse in income between 1929 and the fall of 1931, (2) the steady weakening of the correlation between changes in nominal income and money as the 1930s progressed, (3) the failure of monetary factors to explain the nature and timing of the 1938-41 recovery, and (4) the apparent absence of any tendency for the mechanism of price flexibility to provide strong self-correcting forces as required by an approach that stresses monetary rules and opposes policy activism. Arguing against acceptance of an extreme nonmonetarist interpretation are (1) the close association between the collapse in income and the lagged effect of monetary changes after the fall of 1931, (2) the milder contraction and earlier recoveries associated with the more expansive monetary policies pursued in Europe, (3) the close association between money and income in the 1937-38 recession, and (4) the failure of the price change data to adhere to the expectational Phillips curve approach imbedded in many postwar econometric models constructed by nonmonetarists.

An annular array with fiber composite microstructure for far field NDT imaging applications

This paper describes the design and fabrication of a reduced element count annular array for far field NDT imaging applications, built with a random fiber piezoelectric composite microstructure. An annular array design is considered, spatially it offers axi-symmetric layout while reducing number of array elements, which could potentially result in a significant reduction in the cost and complexity of building an ultrasonic volumetric imaging system. Modelling and preliminary experimental results are presented to evaluate the feasibility of this approach

Movie of the interplanetary magnetic field

Description of movie representing IMP-1 MAGNETOMETER observations of interplanetary magnetic fiel

Interplanetary magnetic field IMP-1, motion picture of the transverse components

Motion picture report of IMP-1 magnetometer observations of interplanetary magnetic fiel

Analytic Framework for Students' Use of Mathematics in Upper-Division Physics

Many students in upper-division physics courses struggle with the mathematically sophisticated tools and techniques that are required for advanced physics content. We have developed an analytical framework to assist instructors and researchers in characterizing students' difficulties with specific mathematical tools when solving the long and complex problems that are characteristic of upper-division. In this paper, we present this framework, including its motivation and development. We also describe an application of the framework to investigations of student difficulties with direct integration in electricity and magnetism (i.e., Coulomb's Law) and approximation methods in classical mechanics (i.e., Taylor series). These investigations provide examples of the types of difficulties encountered by advanced physics students, as well as the utility of the framework for both researchers and instructors.Comment: 17 pages, 4 figures, 3 tables, in Phys. Rev. - PE

Previously Identified Genetic Variants in ADGRL3 Are not Associated with Risk for Equine Degenerative Myeloencephalopathy across Breeds.

Equine neuroaxonal dystrophy/equine degenerative myeloencephalopathy (eNAD/EDM) is a neurologic disease that has been reported in young horses from a wide range of breeds. The disease is inherited and associated with vitamin E deficiency during the first two years of life, resulting in bilateral symmetric ataxia. A missense mutation (chr3:71,917,591 C > T) within adhesion G protein-coupled receptor L3 (ADGRL3) was recently associated with risk for EDM in the Caspian breed. In order to confirm these findings, genotyping of this missense mutation, along with the three other associated single nucleotide polymorphisms (SNPs) in the genomic region, was carried out on 31 postmortem-confirmed eNAD/EDM cases and 43 clinically phenotyped controls from various breeds. No significant association was found between eNAD/EDM confirmed cases and genotype at any of the four identified SNPs (P > 0.05), including the nonsynonymous variant (EquCab2.0 chr3:71,917,591; allelic P = 0.85). These findings suggest that the four SNPs, including the missense variant in the ADGRL3 region, are not associated with risk for eNAD/EDM across multiple breeds of horses

Comparison of the mean photospheric magnetic field and the interplanetary magnetic field

Polarity comparison of solar magnetic field and interplanetary magnetic fiel