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Abstract Luminance adjustment is widely used to evaluate discomfort due to glare. This paper reports an experiment conducted to investigate two factors of the luminance adjustment procedure, stimulus range bias and direct vs indirect control. Stimulus range bias describes the influence on subjective evaluations of the range of stimuli available to the test observer, with range being the minimum and maximum available glare source luminance in the current context. For the glare source, an artificial window, there were three ranges, having maximum luminances of 5 106, 7288 and 9469 cd/m2. The results suggest that luminance range had a significant effect on settings made, sufficient to change settings by an amount equivalent to one step of a Hopkinson-like discomfort sensation scale. The mean luminance associated with just intolerable discomfort with the low range was less than that associated with just uncomfortable with the high range. Past experiments have used direct control, where the observer makes the adjustment directly, and indirect control, where the observer instructs the experimenter to make the adjustment actions. Both methods were used in the current experiment. It was found that range bias was larger when using direct control than with indirect control. These findings contribute to an understanding of why different studies of discomfort glare have reported different results and hence proposed different discomfort models. Graphical abstract Image 1 Highlights • Stimulus range bias in an adjustment procedure was evaluated using three different ranges of luminance. • The influence of control was evaluated using direct (participant) and indirect (experimenter) control to make adjustments. • Larger luminance ranges led to higher glare settings for the same discomfort sensation. • The range bias effect was larger when direct control was used. • Stimulus range bias could explain the inconsistencies found across glare studies. [ABSTRACT FROM AUTHOR]

Abstract Replicating scientific findings is a fundamental aspect of research. However, in studies of discomfort due to glare, it is difficult to make comparisons between the results of different experiments since the statistical tests usually reported do not allow independent findings to be directly compared to each other. Here we present an alternative Bayesian approach that can address this problem. To show how this approach works, we performed a laboratory test with 55 participants to validate the effect of order bias previously detected in a similar study evaluating discomfort due to glare but, this time, under a large luminous source. Using the luminance adjustment procedure, the glare source was varied to meet four sensations of discomfort due to glare. Adjustments were performed under three different order sequences: ascending, descending, and randomised. Test participants provided glare settings using a newly proposed evaluation scale. The effect of order bias detected in the original study was compared to the data obtained with the same methodological procedure in the new experiment using Bayesian inferential tests. The results showed a close replication, highlighting that the order bias effect found in the original study was also present in the new experiment. The wide application of Bayesian methods in the design and analysis of experimental studies may improve the accuracy and validity of glare models. Graphical abstract Image 1 Highlights • Bayesian approach was used to replicate the detection of order effects bias. • Newly developed BEARS glare scale was used to evaluate discomfort due to glare. • Data from an original study was compared against a new replication experiment. • A close replication of the order effect was found. • There is a need to move beyond Null Hypothesis Significance Testing (NHST). [ABSTRACT FROM AUTHOR]

Abstract: A two-point maximum entropy method (TPMEM) was investigated for post-acquisition signal recovery in magnetoencephalography (MEG) data, as a potential replacement of a low-pass (LP) filtering technique currently in use. We first applied TPMEM and the LP filter for signal recovery of synthetically noise corrupted MEG “phantom” data sets in which the true underlying signal was known. Results were quantified with the use of visual plots, percent error histograms, and the statistical parameters root mean squared error and Pearson’s correlation coefficient. Synthetically noise corrupted data from a simulated magnetic dipole was used to quantify the improvements gained in using TPMEM over LP filters in reconstructing known dipole parameters such as position, orientation, and magnitude. Finally, we applied TPMEM and LP filters to a sample MEG patient data set. Our results show that TPMEM has improved noise-reduction and signal recovery capabilities than those of the LP filter, and furthermore data processed with TPMEM shows less error in the reconstructed dipole parameters. We propose that TPMEM can be used for MEG signal processing, resulting in improved MEG source characterization. [Copyright &y& Elsevier]

Emissions of air pollutants from aircraft in large urban areas are a health concern to nearby residents. This study examined hourly concentrations of CO, NOx, SO2, and respirable suspended particles (RSP) taken in the vicinity of Hong Kong International Airport (HKIA) and Los Angeles International Airport (LAX). The LAX data cover the period August 1997 through March 1998 and the HKIA all of 2000 and 2001. The average concentration as a function of wind speed and direction was estimated by nonparametric regression. The error variance of the nonparametric regression results was also estimated. The results show that SO2 can be used to identify wind speeds and directions associated with emissions from aircraft. Using this assumption and the nonparametric regression plots for the other pollutants one can identify the impact of aircraft on local air quality. At LAX, CO and NOx are dominated by emissions from ground vehicles going in and out of the airport. However, near HKIA, aircraft are an important contributor to CO and RSP. At both sites, nonparametric regression identified other, smaller sources as well. [Copyright &y& Elsevier]

Abstract: A two-point maximum entropy regularization method (TPMEM) was investigated for signal enhancement of magnetoencephalography (MEG) data, as a potential replacement for current low-pass (LP) filtering techniques. TPMEM was found to have superior noise reduction and signal recovery capabilities over the LP filter, and MEG data processed with TPMEM yields less error in reconstructed dipole position and orientation. [Copyright &y& Elsevier]

Abstract: Magnetoencephalography (MEG) was recorded while 5–7 year-old children were performing a visual–spatial memory recognition task. Full-term children showed greater gamma-band (30–50 Hz) amplitude in the right temporal region during the task, than children who were born extremely preterm. These results may represent altered brain processing in extremely preterm children who escape major impairment. [Copyright &y& Elsevier]

Abstract: Alpha-particle radiobiological experiments involve irradiating cells with alpha particles and require thin biocompatible materials as substrates for cell cultures, which can record alpha-particle transversals. CR-39 SSNTDs with a thickness of about are suitable substrates. In the present work, the biocompatibility enhancement of these thin CR-39 SSNTDs is studied through superficial pore formation by alpha-particle irradiation. HeLa cells were cultured on these detectors and the biocompatibility was assessed through the number, morphology and average cell area of the cultured cells. For short etching time (15min) in (with subsequent etching in NaOH/ethanol), the biocompatibility of the CR-39 detector is enhanced through superficial pore formation by alpha-particle irradiation. In contrast, for long etching time (60min) in (with subsequent etching in NaOH/ethanol), the biocompatibility of the CR-39 detector deteriorates through superficial pore formation. Possible reasons are discussed. [Copyright &y& Elsevier]