Signals of threat do not capture, but prioritize, attention: A conditioning approach.

Research suggests that threatening information captures attention more rapidly than neutral information. However, in most studies threat stimuli differ perceptually from neutral stimuli and are instrumental to perform the task, leaving the question unanswered whether threat is sufficient to capture attention. In experiment 1, we designed a visual search task with stimuli of equal salience (colored circles) that have the potential to lead to efficient search (10 ms/item). In experiment 2, one of the colors (conditioned stimulus, CS+) was made threatening by means of fear conditioning. Participants responded to a target presented in one of the circles. Overall, the search was faster on congruent trials (where the target was presented in the CS+) than on baseline trials (where the CS + was absent). Furthermore, the search was slower on incongruent trials (where the target was presented in another color than the CS+) than on baseline trials. The search on congruent trials was affected by set size (90 ms/item), but to a lesser extent than on baseline trials (105 ms/item). We conclude that threat prioritizes, but does not capture attention. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Stimulation of large-conductance Ca2+-activated K+ channels by Evans blue in cultured endothelial cells of human umbilical veins

The effect of Evans blue (EB) on large-conductance Ca2+-activated K+ (BKCa) channels was investigated in cultured endothelial cells of human umbilical veins. In whole-cell configuration, EB (50 microM) reversibly increased the amplitude of K+ outward currents (IK). When the patch pipettes were filled with 10 mM EGTA, its stimulatory effect on IK was unaltered. Further application of EB in the presence of suramin, a blocker of P2-purinergic receptor, or AOPCP, an inhibitor of 5'-nucleotidase, still increased IK. However, charybdotoxin (100 nM) suppressed EB-induced increase in IK. In inside-out configuration, bath application of EB (50 microM) did not change single channel conductance but significantly increased the activity of BKCa channels. The EB-induced increase in the activity of BKCa channels was independent on internal Ca2+. EB (50 microM) shifted the activation curve of BKCa channels to less positive membrane potentials by approximately 20 mV. The change in the kinetic behavior of BKCa channels caused by EB in these cells is due to an increase in mean open time and a decrease in mean closed time. These results indicate that EB can stimulate the activity of BKCa channel in endothelial cells. This effect is unrelated to its blockade of P2-purinergic receptors or inhibition of 5'-nucleotidase. The direct stimulation of these ionic channels by EB may contribute to its effect on capillary permeability.     

Increasing Understanding of Technology Management through Challenge Mapping

The authors seek to clarify what is understood by the management of technology by involving a group of managers in a workshop to identify specifically what they believe to be their critical difficulties and challenges in managing technology. The approach is shown to be a means of enhancing creativity, designed not so much for creating good answers and solutions, but rather for discovering good questions and challenges and for conceptualizing complex issues. Virtually all of the challenges selected as most important had much more to do with leading people to think more innovatively and collaboratively than with new technology itself.     

Enhanced visible light photocurrent generation at surface-modified TiO2 nanotubes

Photoelectrodes consisting of TiO₂ nanotube layers with different thicknesses (0.5 μm, 1.7 μm, 3 μm, 6 μm, 9 μm, and 18 μm) were prepared by anodization of titanium substrates and subsequent surface modification by a heat treatment at 400 °C in the presence of urea pyrolysis products. In contrast to unmodified TiO₂ nanotubes, the modified photoelectrodes exhibit photocurrents under visible light irradiation down to 750 nm. Photocurrent transients indicate enhanced recombination unless a suitable hole-scavenger, like iodide, is present since the photogenerated holes do not oxidize water efficiently. In the visible light the photoconversion efficiency increases significantly with nanotube length. The maximum incident photon-to-current efficiency (IPCE) was observed for tubes with the length of 6-9 μm (IPCE ∼4.5% and 1.4% at 450 nm and 550 nm, respectively) and the photocurrent enhancement with increasing tube length is found to be stronger at longer irradiations wavelengths.     

Book Review

The objective of the present study was to investigate the effect of various terpenes, including a diterpene, forskolin (FSK; a putative penetration enhancer), on skin permeation of valsartan. Permeation studies were carried out with Automated Transdermal Diffusion Cells Sampling System (SFDC 6, LOGAN Instruments Corp., NJ, USA) through rat skin and human cadaver skin (HCS) using ethanol: IPB (pH 7.4) (40:60) as vehicle. The efficacy of the study terpenes for permeation of valsartan across rat skin and human cadaver skin was found in the order of cineole > d-limonene > l-menthol > linalool > FSK and cineole > d-limonene > linalool > l-menthol > FSK, respectively. No apparent skin irritation (erythema, edema) was observed on treatment of skin with terpenes including FSK. FT-IR, DSC, and histopathological studies revealed that FSK enhanced the skin permeation of the active drug by disruption and extraction of lipid bilayers of SC in consonance with other terpenes.     

A general result on the uniform in bandwidth consistency of kernel-type function estimators

We develop a general theorem to prove the uniform in bandwidth consistency of kernel-type function estimators. This method unifies the approaches in some other recent papers. We show how to apply our results to kernel distribution function estimators and the smoothed empirical process. The results are applicable to establish strong uniform consistency of data-driven bandwidth kernel-type function estimators.     

Comparison of Kayzero for Windows and k0-IAEA software packages for k0 standardization in neutron activation analysis

For many years the well-established Kayzero for Windows software for neutron activation analysis (NAA) using k₀ standardization was the only commercial program available. Recently, the freeware k0-IAEA software has been launched by the International Atomic Energy Agency (IAEA). The software is based on an adapted Høgdahl convention in which the cadmium cut-off energy from the k₀-formulas is removed. The holistic approach of γ-ray spectra evaluation is used which minimizes the user's interaction with the software.Several certified reference materials were analyzed with the k0-IAEA and Kayzero for Windows software using the same gamma-ray spectra obtained from several irradiation and counting modes. The results obtained were compared and evaluated in terms of precision, accuracy and detection limits. The work-flow procedures performed by the two software packages and the results obtained are discussed.