Illusory tilt and Euclidean schemes as factors in performance on the water-level task.

Predictions made by models of water-level acquisition were tested to understand better the sensory factors, cognitive factors, or both, that differentiate people who fail the test (low scorers) from people who pass (high scorers). Experiments 1 and 2 showed that in a horizontal-edge detection task, low scorers were less likely than high scorers to "see" liquid edges in tilted containers as horizontal. Experiment 3 showed that water-level type displays belong to a class of tilt illusions that arise from early visual processes for both low and high scorers, but only high scorers spontaneously use cognitive schemes to minimize illusory tilt. In Experiment 4, high scorers, but not low scorers, overrode the orientation illusion in a production task. The findings suggest bottom-up processes cause embedded lines to be misperceived for both groups, but high scorers are more likely to use cognitive schemes spontaneously to overcome the orientation illusion. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Strategy use on standardized reading comprehension tests.

Strategy use and its impact on standardized reading test performance were investigated. High school students were randomly assigned to 2 groups, standardized test and main idea, with separate control and think-aloud conditions. In the standardized think-aloud group, students thought aloud while taking a portion of a reading test, consisting of passages accompanied by several questions each. In the main idea conditions, students read the same passages with the lower level questions removed and answered a single multiple-choice question about the main idea of each passage, having been told that the task was not a test. Both groups used strategies, and students in the standardized test condition made significantly greater use of strategies than students in the main idea condition. Significant between-group differences were found in use of rereading. In comparisons between the think-aloud and control conditions, thinking aloud was found to have a significant detrimental effect on students' ability to identify passage main ideas. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Eye tracking in patients with unipolar and bipolar affective disorders in remission.

Examined patients (20–66 yrs old) with a history of recurrent affective disorder on a variety of smooth-pursuit and saccadic eye-tracking tasks and on psychomotor analogs of these tasks. The 25 unipolar and 24 bipolar Ss were compared to 24 schizophrenics; all Ss were in remission. Results indicate that the performance of the 2 affective-disorder groups was not significantly different from that of the controls on any of these tasks. Smooth-pursuit tracking error was greater for Ss receiving Li and for those with a higher frequency of prior episodes of the disorder. When the pursuit eye movements of these Ss were compared to those of the schizophrenics, the latter produced more tracking error than both affective-disorder groups but significantly so only with respect to unipolar Ss. Although findings are consistent with the interpretation that tracking dysfunction is not a trait characteristic of affective disorders, further investigations contrasting remitted patients with bipolar and schizophrenic disorders are needed to determine the specificity of deviant tracking to schizophrenia. (38 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Faraday rotation data analysis with least-squares elliptical fitting

A method of analyzing Faraday rotation data from pulsed magnetic field measurements is described. The method uses direct least-squares elliptical fitting to measured data. The least-squares fit conic parameters are used to rotate, translate, and rescale the measured data. Interpretation of the transformed data provides improved accuracy and time-resolution characteristics compared with many existing methods of analyzing Faraday rotation data. The method is especially useful when linear birefringence is present at the input or output of the sensing medium, or when the relative angle of the polarizers used in analysis is not aligned with precision; under these circumstances the method is shown to return the analytically correct input signal. The method may be pertinent to other applications where analysis of Lissajous figures is required, such as the velocity interferometer system for any reflector (VISAR) diagnostics. The entire algorithm is fully automated and requires no user interaction. An example of algorithm execution is shown, using data from a fiber-based Faraday rotation sensor on a capacitive discharge experiment.     

Nickel release from inexpensive jewelry and hair clasps purchased in an EU country — Are consumers sufficiently protected from nickel exposure?

Background

Nickel allergic subjects are at risk factor of acquiring hand eczema. In 1990 and 1994, respectively, Denmark and member states in the EU regulated nickel release from selected consumer products. The intention was that the nickel epidemic could be controlled and prevented if the general population was protected from high cutaneous nickel concentrations. Despite a decrease, the prevalence of nickel allergy remains high as nearly 10% of young women are nickel allergic.

Objective

This study aimed to perform dimethylglyoxime (DMG) testing of inexpensive jewelry and hair clasps purchased from random stores in Copenhagen, Denmark to detect the proportion of items that may result in nickel allergy.

Methods

Inexpensive jewelry and hair clasps were purchased from 36 stores and street vendors in Copenhagen and were later tested for nickel release using the DMG test.

Results

The study showed that 19.3% hair clasps, 14.8% earrings, and 12.9% necklaces intended for adult women released an excessive amount of nickel. Of 25 stores visited, 36.0% sold DMG positive jewelry. For items designed for children, excessive nickel release was identified in hair clasps (79.4%) and in finger rings (20%). Four (50.0%) of 8 children clothing stores sold jewelry that released too much nickel.

Discussion

Excessive nickel release has been regulated since 1990 in Denmark. However, 1/5 of purchased items released nickel in concentrations that may lead to nickel allergy. Especially hair clasps intended for children released an excessive amount of nickel.     

European interlaboratory trial regarding the official microscopic method for the detection of the presence of animal constituents in feedstuffs

The bovine spongiform encephalopathy epidemic is thought to have occurred as a consequence of feeding prion-infected material to cattle. To avoid the risk of bovine spongiform encephalopathy diffusion, the European Commission (Directive 2003/126/EC) established an official method to detect the presence of animal-derived constituents in feedstuffs, using microscopic examination. This method allows easy identification of bone fragments among other animal constituents. The analysis is based on morphological conformation of the fragments and their characterization (mainly of the shape of lacunae) to discriminate among mammalian, poultry, and fish tissues. The aim of this study was to assess the performances of nine European laboratories through a ring trial of the official microscopic method, and to calculate accuracy and reproducibility of the method. In general the reproducibility of the microscopic method was very good (kappa overall = 0.83), with a high sensitivity for all laboratories. Concerning the analysis on the different animal-derived constituents, the results show values of sensitivity with large variability between fish and poultry or mammal. It was generally more difficult to discriminate between mammalian and poultry tissues than fish tissue.