The accuracy of self-monitoring and its relationship to self-focused attention in dysphoria and clinical depression.

The accuracy with which dysphoric (Study 1) and clinically depressed (Study 2) individuals make self-regulatory judgments about their own performance in the absence of external feedback and the extent to which this relates to trait self-focused attention (SFA) were examined. Relative to objective criteria, both dysphoric and depressed participants showed a positive judgment bias, overestimating the number of trials they had performed correctly. Relative to control participants, the dysphoric and depressed groups showed a reduction in the extent of this positive bias in that they judged error trials more accurately and correct trials less accurately. Although the dysphoric and depressed groups both reported elevated trait SFA, this did not correlate significantly with accuracy of self-judgment on the performance-monitoring task. Implications for self-regulation models of depression are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A possible structure of the casein micelle based on high-resolution field-emission scanning electron microscopy

New electron micrographs, produced using the technique of Field Emission Scanning Electron Microscopy, showing the details of the micellar surface, are presented. The images show the micellar surfaces without any coating, and suggest that the surface of the micelle may have a much more complex structure than has previously been demonstrated. Although there appear to be no spherical subunits (submicelles), there is evidence for the organization of the caseins into tubular structures within the micelle. The surface is not smooth, and contains gaps between the substructures. The observations are discussed in terms of published models of micellar structure, where is it suggested how the depiction of the micellar surface can be used to explain certain factors of its reactivity and behaviour.     

The effects of suppressing a negative autobiographical memory on concurrent intrusions and subsequent autobiographical recall in dysphoria.

Depressed individuals endeavor to suppress intrusive thoughts and memories as a form of mood control. Two predictions from this literature were examined. The 1st was that attempts to suppress a preselected negative memory during a stream-of-consciousness (SOC) task in dysphoric individuals, relative to a no-suppress condition, would lead to relatively speeded access to other negative but not positive memories on a subsequent cue-word recall task. No such effects were predicted for nondysphoric controls. The 2nd prediction was that, across all participants who were asked to suppress memories, higher levels of depressed mood would be associated with more intrusions of the to-be-suppressed memory during the SOC and that this association would be stronger than the comparable relation in participants who were not asked to suppress memories. Results support both predictions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Latency–probability curves for sequential decision models: A comment on Weatherburn.

Discusses D. Weatherburn's (see record 1979-25180-001) mathematical argument that shows that the relationship between response latency and response probability in sensory discrimination experiments does not determine the form of an underlying sequential decision process unless the time rates for implicit events are also specified. This argument is not denied, but in many cases the expected variation of time rates is not sufficient to rule out the use of the latency–probability graph. This is particularly the case if time rate variation is directly determined by stimulus magnitude or if variations due to motivation occur only from trial to trial rather than from session to session. It is concluded that, even if such variation is large, there is a considerable amount of information to be gained from latency–probability analysis. (13 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A double-blind placebo-controlled phase II trial of thalidomide in asymptomatic HIV-positive patients: clinical tolerance and effect on activation markers and cytokines

A randomized double-blind, placebo-controlled study was performed to determine the safety, efficacy, and effect of thalidomide on a variety of immunological and biochemical parameters in asymptomatic human immunodeficiency virus (HIV)-positive patients. Nineteen male patients with elevated markers of immune activation and CD4 cell counts above 400/mm3 were randomized to either placebo or thalidomide at 100 mg/day for 24 weeks. However, only 3 (of 10) patients receiving thalidomide completed all 24 weeks compared to 6 (of 9) patients receiving placebo. This was mainly due to fatigue (somnolence is a recognized side effect), although this was also seen to a lesser extent in the placebo group and so may not be drug attributable. No significant changes in CD4/CD8 count, activation markers, TNF-alpha, or TNFR1 were observed. However, a nonsignificant trend toward inhibition of mitogen-induced TNF-alpha production was observed in the thalidomide arm. The lack of systemic effect and the lower tolerance of thalidomide (at this dose) in asymptomatic patients highlights the need for pharmacokinetic analysis to address possible absorption problems and the need for more potent and less toxic TNF-alpha inhibitors to be developed for use in this type of study.     

Memory for emotional trait adjectives in clinically depressed youth

An experiment was conducted to examine memory for emotional trait adjectives in depressed children and adolescents. Two groups of children and adolescents, clinically depressed participants and non-clinical controls, were compared on computerized versions of recall and recognition memory tasks. Three groups of words (positive trait adjectives, negative trait adjectives, and categorized neutral words) were used in the experiment. Results showed that the depressed group recalled significantly more negative adjectives than positive adjectives, whereas the control group recalled the same number of positive and negative adjectives. This effect was predicted by the association between age and level of depression, with the depression-related bias becoming stronger with age. Signal detection analysis revealed that the depressed group did not show any bias in the recognition task. The findings are discussed with respect to cognitive theories of depression with consideration of the developmental implications.     

Experiments in laser-assisted visual sensing for AUV navigation

The Cranfield University torpedo-shaped underwater vehicle has been modified to accommodate a laser stripe illumination system. As well as providing enhanced viewing capabilities, this system derives real-time navigational data during the mission and gathers images to produce a post mission enhanced optical waterfall image of a surveyed area.

This paper describes a preliminary set of constrained motion trials at the IFREMER wave basin in Brest, where the system was towed through the 50 m test tank at different altitudes and orientations whilst the true trajectory was measured. A comparison is made between ground truth trajectory generated from these external measurements and that derived from the video camera and rotation sensors internal to the vehicle.     

The fracture energy of bimaterial interfaces

This article describes a framework applicable to the measurement and interpretation of the fracture energy of bimaterial interfaces. A major conclusion of this study is that the fracture energy, Γ_i, is not unique and usually exhibits values substantially larger than the thermodynamic “work of adhesion. ” The lack of uniqueness is related to mode mixity (shear/opening) effects experienced by interface cracks, as characterized by the phase angle of loading, ψ: typically, Γ_i, is found to increase as ψ increases. These trends are attributed to crack shielding caused by roughness of the interface fracture surface, to material nonlinearity,etc. The phase angle is, in turn, influenced by the choice of test specimen, resulting in values of Γ_i that differ between specimens in a manner attributed to the locus of Γ_i with ψ. Preliminary models that relate Γ_i to roughness, plasticity, segregation,etc., are described, leading to insights concerning microstructural aspects of “weaklrd and “strong” interfaces. This paper is based on a presentation made in the symposium “Interface Science and Engineering” presented during the 1988 World Materials Congress and the TMS Fall Meeting, Chicago, IL, September 26–29, 1988, under the auspices of the ASM-MSD Surfaces and Interfaces Committee and the TMS Electronic Device Materials Committee.     

Information processing in recovered depressed children and adolescents

Previous research into subjective probability estimates for negative events revealed that depressed children estimated events as equally likely to happen to themselves as to other children. In contrast, both controls and anxious children estimated that negative events were more likely to happen to others than to themselves. The present study followed up this finding by investigating the subjective probability judgements concerning future negative events generated by children and adolescents who have recovered from depression. Subjects generated probability estimates either for themselves or for other children for a range of negative events on a visual analogue scale. The results revealed that both recovered depressed and matched control groups estimated negative events as significantly more likely to happen to others than to themselves. It was also found that the recovered depressed subjects estimated that negative events were less likely overall, compared to the controls. These results are discussed in the context of the adult literature.