Disrupted retrieval in directed forgetting: A link with posthypnotic amnesia.

Findings from research on directed forgetting seem difficult to accommodate in terms of theoretical processes, such as selective rehearsal or storage differentiation, that have been put forward to account for directed-forgetting phenomena. Some kind of "missing mechanism" appears to be involved. To circumvent the methodological constraints that have limited the conclusions investigators could draw from past experiments, the present author describes a new paradigm that includes a mixture of intentional and incidental learning. Four experiments with 234 undergraduates tested the paradigm. A midlist instruction to forget the 1st half of a list was found to reduce later recall of the items learned incidentally as well as those learned intentionally. This result suggests that a cue to forget can lead to a disruption of retrieval processes as well as to alteration of encoding processes postulated in prior theories. Results also provide a link between intentional forgetting and the literature on posthypnotic amnesia, in which disrupted retrieval has been implicated. With each of these procedures, the information that can be remembered is typically recalled out of order and often with limited recollection for when the information had been presented. It is concluded that retrieval inhibition plays a significant role in nonhypnotic as well as in hypnotic instances of directed forgetting. The usefulness of retrieval inhibition as a mechanism for memory updating is discussed. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Frequency of the carrier state for X-linked chronic granulomatous disease among females with lupus erythematosus

Carriers for chronic granulomatous disease (CGD) and patients with lupus erythematosus (LE) share several characteristics: They are mostly females, they reduce nitroblue tetrazolium (NBT) poorly in their neutrophils, and, in some cases, they have similar skin lesions. We thus investigated 19 female LE patients for the presence of laboratory findings characteristic of the carrier state for CGD. None of these patients turned out to have the combined abnormality of neutrophil bactericidal activity and neutrophil NBT-reduction that is diagnostic of CGD carrier state in the X-linked form. An increased frequency of CGD carriers among female LE patients thus appear to be unlikely. Why some CGD carriers develop skin lesions typical of LE remains unexplained.     

The P300 as an electrophysiological probe of alcohol expectancy.

Language-based measures indicate that alcohol expectancies influence alcohol consumption. To relate these measures to brain actions that precede verbal output, the P300 component of the Event-related potentials (ERPs) was used to detect violations of individually held alcohol expectancies. As predicted, P300 amplitude elicited by negative alcohol expectancy stimuli was positively correlated with endorsement of positive/arousing alcohol expectancies on the language-based measures, such that the higher an individual's positive/arousing expectancies, the larger was the P300 elicited by negative alcohol expectancy stimuli. These results demonstrated concordance between language-based measures of alcohol expectancies and electrophysiological probes of expectancy. While it remains unknown whether these expectancy processes are integral to decision pathways that influence consumption, these findings suggest that such processing can occur very quickly outside of conscious deliberation. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Recent studies of particle packing in organic coatings

Organic coatings often contain sufficient pigmentation that the pigment volume concentration (PVC) and the critical PVC (CPVC) must be carefully considered. Past work has shown that the CPVC can be identified with the random densest packing of pigment particles after considerations of the adsorbed polymer layer on the particles is taken into account, and that this packing can be predicted by empirical particle packing algorithms developed for mixtures of particle sizes. Recent studies have shown that local fluctuations of pigment and polymer concentrations in a film can lead to local film volumes that can exceed the CPVC even though the average PVC for the whole film (the global PVC) is below the CPVC. These effects are consistent with observations of void formation in films below the CPVC, and can be analyzed by local film statistics. We have also recently performed simulations of particle packing by the compression of multiple hard spheres that allows further insight into local concentration fluctuations in PVC within a film.     

Optical probing of anisotropic heat transport in the quantum spin ladder Ca9La5Cu24O41

A transient thermal imaging technique is used to monitor heat diffusion at the surface of the antiferromagnetic spin ladder material Ca₉La₅Cu₂₄O₄₁. This material shows highly anisotropic thermal conductivity due to a large uni-directional magnetic heat transport along the ladders. The thermal conductivity is measured using optical heating as well as electrical heating, yielding 37 ± 3 W m^?1 K^?1 for the fast (ladder) direction and 2.5 ± 0.5 W m^?1 K^?1 for the slow direction, respectively. The fast direction result is in agreement with the thermal conductivity measured using other dynamic methods, but about 60% lower than the thermal conductivity measured using steady state methods.     

Magnetic properties of mechanically activated SmMnO3 powders

Magnetic properties of the initial (pre-milling) and mechanically activated SmMnO₃ polycrystalline powders were studied. Magnetization measurements were carried out in the temperature range of T = 4–300 K and the magnetic fields up to ±20 kOe. The powders were subjected to both high-energy and low-energy ball milling. The samples studied were analyzed by X-ray diffraction method and X-ray photon-emission spectroscopy. It was found that all the mechanically activated powders SmMnO₃ have significantly different magnetic characteristics (transition temperatures, coercive forces, remanent magnetizations) in comparison with initial samarium manganite. The inversion of field cooled (FC) and zero-field cooled magnetizations was observed for the initial sample only. Mechanically activated samples demonstrate positive FC magnetizations in the whole measured temperature range. It is established that the magnetic properties of the samples are strongly dependent on the mode of mechanical activation. Much noticeably, modifications in magnetic characteristics of powder studied were obtained in the case of low-energy mechanical treatment.     

Evaluation of the effect of free gas on the measurement error for crude oil mass by coriolis flowmeters and dissolved gas on the error of measuring well production rate

Results are presented for experimental studies of estimating the effect of free gas on the metrological properties of coriolis flowmeters. The requirement is demonstrated for considering gas dissolved in oil during measurement of well production rate.