Long-term stability and intercorrelations of cognitive abilities in older persons.

This project studied the intercorrelations and long-term stabilities of standard Wechsler Adult Intelligence Scale—Revised (WAIS—R), Wechsler Memory Scale—Revised (WMS—R), and Auditory–Verbal Learning Test (AVLT) summary indexes. It also reports similar data on the recently published Mayo Cognitive Factor Scales (MCFS), which are derivative indexes for the combined administrations of these 3 tests. These analyses challenge 2 assumptions that most psychologists make when interpreting adult cognitive tests: (a) that for cognitively normal people, performance in one cognitive domain correlates well with and predicts functioning in other cognitive domains, and (b) that in the absence of pathology, cognition is stable. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Relating laboratory and outdoor exposure of coatings: II

The effect of relative humidity (RH) from ≪1% to 90% on the photodegradation and quantum efficiency for a partially-methylated melamine acrylic coating exposed to UV/50°C condition has been investigated. The UV source is supplied by two 1000 W Xenon arc solar simulators and the relative humidities are provided by specially designed humidity generators, which control relative humidity in the 0 to 90% range to within <3% of the measured values. Radiation absorbed in the coating and degradation of the films are measured by UV-visible and Fourier transform infrared spectroscopies, respectively. The degradation at a particular RH/UV condition consists of four different modes: reactions taken place during post curing, hydrolysis due to water in the film at a particular RH, photodegradation, and moisture-enhanced photodegradation. Total degradation, hydrolysis, and moisture-enhanced photodegradation increase with increasing RH. At low relative humidities, photodegradation is an important degradation mode but hydrolysis dominates the degradation at high RH levels. Moisture in the film is found to increase the quantum efficiency of acrylic melamine coating photodegradation. 100 Bureau Dr., Stop 8621, Gaithersburg, MD 20899.     

Doping properties of selected impurities in Hg1−x Cdx Te

The doping properties of selected impurities in Hg_1-x Cd_x Te have been determined. Primary emphasis is on elements from Groups IB and IIIA, expected to substitute on the metal sublattice, and on elements from Groups VA and VIIA, expected to substitute on the Te sublattice. In addition, the behavior of some elements from Group IV as well as behavior of Li has been determined. Impurities were introduced into Hg_1-x Cd_x Te either by diffusion or during crystal growth. Cu, Ag and Li are fast diffusing acceptors, Ga is a fast diffusing donor, Al and Si are donors which require high diffusion temperature to effect diffusion, P and As are slowly diffusing acceptors and Br is a slowly diffusing donor. Sn appears to be inactive. In general, impurities substituted on the metal sublattice are rapid diffusers while those substituted on Te sites are slow diffueers. Supported in part by the Air Force Materials Laboratory, WPAFB, Ohio.     

Associative tolerance to nicotine analgesia in the rat: Tail-flick and hot-plate tests.

Previous assessments of associative nicotine tolerance may have confounded associative effects with novelty-induced stress effects, instrumental learning effects, or both. That is, subjects were tested in novel environments, allowed to practice the test response, or both during the tolerance development phase. In the first study, 32 male Sprague-Dawley rats were injected with various doses of nicotine and tested for nociception in the tail-flick and hot-plate tests to assess nicotine's analgesic effects. In the second study, 35 rats received nicotine explicitly paired or unpaired with a distinctive test context. All animals were equally preexposed to the test environment, and none had the opportunity to practice the test response. Paired rats developed greater nicotine tolerance than unpaired rats. This context-dependent (associative) tolerance effect was found with both tail-flick and hot-plate tests. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Reestimating Zajonc's confluence effects on the SAT.

In response to the article by R. B. Zajonc (see record 1987-02628-001) on the confluence model and prediction of national Scholastic Aptitude Test (SAT) scores, the present authors reestimate Zajonc's model using their estimates of proportion of high school seniors taking the SAT. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Nontidal wetland mapping in South Carolina using airborne multispectral scanner data

High resolution multispectral scanner (MSS) imagery of Savannah River nontidal wetlands were analyzed to identify 1) useful spectral bands for discriminating among National Wetland Inventory classes, 2) where the classes cluster in n-dimensional feature space, and 3) what wetland classification accuracies can be expected. Spectral measurements in the green (0.55–0.60 μm), red (0.65–0.70 μm), and near-infrared wavelengths (0.70–0.79 μm and 0.92–1.10 μm) provided the most useful information. Emergent marsh (both persistent and nonpersistent), scrub-shrub, mixed deciduous swamp forest, and mixed deciduous upland forest were found to cluster in somewhat predictable regions of 2- and 3-dimensional feature space. The overall classification accuracy of the Steel Creek delta study area was 83% and was assessed by comparing the remote sensing derived thematic map with 1325 linear meters of transects sampled in situ. These results suggest that high resolution aircraft MSS data can provide detailed vegetation type information for mapping both thermally affected and rejuvenating nontidal wetland in the South Carolina Savannah River Swamp System.     

Convection in stars

This paper reviews work on stellar convection theory with a particular emphasis on numerical simulations of convection. The Boussinesq and the anelastic approximations of the fluid equations are introduced and solutions of the linearized equations for the onset of convection are described. Non-linear numerical solutions to the Boussinesq equations are discussed. Next, the character of stellar convection is considered. Convection is found to be intimately linked with a number of proceses in the stellar interior. Studies of stellar convection have either attempted to model a star with a very simplified treatment of convection or to solve the fluid equations for a range of parameters less extreme than those found in stars. Finally, a brief review is given of some of the numerical methods that have been employed.     

Precision in the measurement of meat texture

The relationships between the level of precision, the variability within muscles and the number of measurements required to assess toughness were quantified in an attempt to rationalise the measurement of meat texture. Variability within M. longissimus dorsi was higher than in other hindquarter muscles of lamb and beef and was less in pork than in beef or lamb. Ten replicate determinations on lamb and beef and seven on pork M. longissimus dorsi would be suited to research work. Under these conditions, 95% of values for each muscle would lie within one-sixth of the texture scale from the mean for 85% of muscles and would lie within one-tenth of the texture scale from the mean for 50% of muscles.     

Redispersion of indoor surface contamination: A review

The importance of surface contamination as a potential source of exposure to hazardous materials is discussed. Data from the literature concerning the resuspension of indoor surface contamination are presented. Reported procedures for quantitating surface contamination are compared. It is suggested that, despite its limitations, surface contamination monitoring may be useful in estimating potential risks from hazardous materials.     

Star couplers using fused biconically tapered multimode fibres

We report the fabrication and testing of 4-, 7-and 19-fibre fused biconical taper transmissive star couplers for use with single multimode fibres. Overall insertion losses on six couplers range from ?1.3 dB to ?2.6 dB. Losses are nearly independent of N, the number of fibres, but dispersion of the powers in the output fibres increases significantly with N.