Behavioral effects of a noisy environment: Task involvement versus passive exposure.

Compared the effects of noise under active task involvement as opposed to passive exposure, using 80 undergraduate Ss who were assigned to 1 of 4 conditions representing 2 * 2 combinations of task vs no task and noise vs quiet. Performance on a dial-monitoring task was unaffected by noise. Ratings of interest and tenseness were significantly higher under the task condition; tenseness was also higher under noise. On a posttest of resistance to frustration, both noise groups, regardless of task condition, showed a smaller degree of persistence on insoluble puzzles than the no-noise groups. Results suggest that aftereffects of noise are not dependent on the power of noise to disrupt task performance. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interpersonal behavior of depressive individuals in a mixed-motive game.

100 undergraduates were selected as Ss on the basis of their scores on the Beck Depression Inventory, a short form of the MMPI, and the Fear Survey Schedule. Three groups of Ss (depressed, nondepressed/other psychological problems, and normal) interacted with a same-sex normal person in a modified Prisoner's Dilemma procedure in which each player's relative power was manipulated. Dyads also had several opportunities to exchange communications during the game. Results indicate that when depressed Ss were in the high-power role, the interactive pattern in the Prisoner's Dilemma procedure was relatively exploitive and noncooperative. High-power depressed Ss also displayed elevation in communications of self-devaluation/sadness and helplessness. This array of behaviors elicited noncooperativeness, extrapunitiveness, and expressions of helplessness in their normal partners. Depressives in the low-power role exhibited no unique game behaviors but communicated self-devaluation and helpless messages; and in addition, they tended to blame their partner for their devalued condition—a pattern that elicited more ingratiating behaviors in their normal partners. (19 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Heat transfer in inertial confinement fusion reactor systems

The short time and deposition distance for the energy from inertial fusion products results in local peak power densities on the order of 10¹⁸ W/m³. This paper presents an overview of the various inertial fusion reactor designs which attempt to reduce these peak power intensities and describes the heat transfer considerations for each design.     

Long-Term Neuroelectric Signal Recording from Severed Nerves

Six recording electrode units were implanted around the severed sciatic nerves of rabbits immediately after an axotomy was performed. Voluntary and involuntary motor neuroelectric signals (including individual action potentials) were recorded from the surface of the severed nerve for as long as 142 days after implantation, the average duration being 64 days. In order to study the course of the limited duration of the signal detection, a stimulation electrode was implanted around the sciatic nerve proximal to the lesion; evoked neuroelectric signals were recorded throughout the length of the experiment. The impedance of the recording electrode was also measured throughout the length of the experiment. The behavior of the above parameters, combined with histological observations, indicated that nerve degeneration accounted for the deterioration of signal detection.     

International intercomparison of absolute reflectance scales

An intercomparison of the absolute reflectance scales of NBS, Washington, D.C. (USA), NRC, Ottawa (Canada), and PTB, Braunschweig (FRG) was organized by sending two samples of Russian opal glass MS-20 to the three laboratories. An additional exchange of a Halon sample between NBS and NRC was arranged. The results of this intercomparison are presented. They show that the three different geometries used at the three laboratories yield values which agree to within ±0.1%.     

Fiber-optic infrared reflection absorption spectroscopy for trace analysis on surfaces of varying roughness. Part II: Acetaminophen on stainless steel

Investigations of the effects of surface roughness on the utility of grazing-angle Fourier transform infrared reflection absorption spectroscopy (IRRAS) as a method for quantifying trace contamination of metal surfaces have been extended to acetaminophen, a model active pharmaceutical agent, on 316 stainless steel. The effects are more complicated than for the surfactant sodium dodecyl sulfate (SDS) on stainless steel; they include a strong surface-finish dependence of sensitivity and nonlinear behavior at surface loadings above approximately 1-2 microg cm(-2). Using data from samples in the loading range 0-0.5 microg cm(-2), unbiased partial least squared calibrations can be readily achieved for individual surface finishes with detection limits of L(D) approximately 0.15 microg cm(-2). However, as found for SDS on stainless steel, models built using data from samples of mixed surface roughness are more problematic.     

Time-dependent effects of pre-aging polymer films in cell culture medium on cell adhesion and spreading

We have tested the hypothesis that cell adhesion and spreading on polymer films are influenced by the amount of time that the polymer films are pre-aged in cell culture medium. Cell adhesion and spreading were assessed after a 6-h culture on poly(d,l-lactic acid) (PDLLA) films that had been pre-aged in cell culture medium for 30 min, 1, 3 or 7 d. Cell adhesion and spread area were enhanced as the duration of pre-aging PDLLA films in cell culture medium was increased. Materials characterization showed that the hydrophobicity and surface morphology of the PDLLA films changed with increasing length of pre-aging time. These results suggest that cell adhesion and spreading are sensitive to the time-dependent changes in PDLLA hydrophobicity and surface morphology that occur during exposure of the polymer to cell medium for different lengths of time. These results demonstrate that cell response to a degradable, biomedical polymer can change as a function of the amount of time that the polymer is exposed to physiological medium. This article, a contribution of the National Institute of Standards and Technology, is not subject to US copyright.     

Aberrant spatiotemporal activation profiles associated with math difficulties in children: A magnetic source imaging study.

The study investigates the relative degree and timing of cortical activation in parietal, temporal, and frontal regions during simple arithmetic tasks in children who experience math difficulties. Real-time brain activity was measured with magnetoencephalography during simple addition and numerosity judgments in students with math difficulties and average or above average reading skills (MD group, N = 14), students with below average scores on both math and basic reading tests (MD/RD group, N = 16) and students with above average scores on standardized math tests (control group, N = 25). Children with MD showed increased degree of neurophysiological activity in inferior and superior parietal regions in the right hemisphere compared to both controls and MD/RD students. Left hemisphere inferior parietal regions did not show the expected task-related changes and showed activity at a significant temporal delay. MD students also showed increased early engagement of prefrontal cortices. Taken together, these findings may indicate increased reliance on a network of right hemisphere parietal (and possibly frontal areas as well) for simple math calculations in students who experience math difficulties but perform within normal range in reading. (PsycINFO Database Record (c) 2010 APA, all rights reserved)