Effects of load stressors, cognitive complexity and type A coronary prone behavior on visual-motor task performance

In two separate experiments, 25 and 42 adult working males participated in a visual-motor task modeled on a video game. The game was designed to permit measurement of strategy, risk taking, errors committed, and overall task performance. Predictions of complexity theory for task performance were supported. In the second experiment, participants were divided into four subgroups on the basis of Type A versus Type B coronary-prone behavior (measured on the structured interview) and on the basis of unidimensional versus multidimensional responding (measured by a complexity interview with stems of the sentence completion test). Type A coronary-prone behavior did not contribute to differences in visual-motor performance. More multidimensional persons exceeded their unidimensional counterparts, especially in the application of strategy. The extension of complexity theory approaches to simpler tasks is discussed. It is noted that the frequently voiced assumptions of Type A individuals-that their behavior style tends to lead to higher performance levels-is not supported.     

Impaired associative taste learning and abnormal brain activation in kinase-defective eEF2K mice

Memory consolidation is defined temporally based on pharmacological interventions such as inhibitors of mRNA translation (molecular consolidation) or post-acquisition deactivation of specific brain regions (systems level consolidation). However, the relationship between molecular and systems consolidation are poorly understood. Molecular consolidation mechanisms involved in translation initiation and elongation have previously been studied in the cortex using taste-learning paradigms. For example, the levels of phosphorylation of eukaryotic elongation factor 2 (eEF2) were found to be correlated with taste learning in the gustatory cortex (GC), minutes following learning. In order to isolate the role of the eEF2 phosphorylation state at Thr-56 in both molecular and system consolidation, we analyzed cortical-dependent taste learning in eEF2K (the only known kinase for eEF2) ki mice, which exhibit reduced levels of eEF2 phosphorylation but normal levels of eEF2 and eEF2K. These mice exhibit clear attenuation of cortical-dependent associative, but not of incidental, taste learning. In order to gain a better understanding of the underlying mechanisms, we compared brain activity as measured by MEMRI (manganese-enhanced magnetic resonance imaging) between eEF2K ki mice and WT mice during conditioned taste aversion (CTA) learning and observed clear differences between the two but saw no differences under basal conditions. Our results demonstrate that adequate levels of phosphorylation of eEF2 are essential for cortical-dependent associative learning and suggest that malfunction of memory processing at the systems level underlies this associative memory impairment.     

High-pressure electrical resistivity behaviour of nanocrystalline perovskite (La,Sr)(Mn,Fe)O3

We report here the electrical resistivity of nanocrystalline perovskite-structured La–Sr manganites as a function of pressures up to 8?GPa, at room temperature. The nanocrystalline perovskite manganites were prepared by the sol–gel technique and found to have crystallite sizes of 12–18?nm. The pressure dependence of the electrical resistivity shows a first-order phase transition at 0.66(2)?GPa and a subtle phase transition between 3.5 and 3.8?GPa. The first-order transition at 0.66?GPa can be related to the transition from localized-electron to band magnetism.     

A Feminist Lutheran Substantive Christology: Method and Methodology

Abstract : From a Euro‐American feminist perspective, not only the methods of North American ‘mainstream’ Christology but also of much feminist Christology needs refinement. The former must take into account the context of feminist consciousness, with particular attention to experience. The latter must reclaim kerygma and dogma. Drawn from history, kerygma, dogma, and experience, feminist Lutheran Christology is substantive, meaning that Jesus Christ is fully human and fully divine and sufficient for salvation.     

Perceived Social Support and Type of Cardiac Procedures as Modifiers of Hospital Anxiety and Depression

This study examined the effect of cardiac procedure and perceived social support on anxiety and depression among cardiac patients. The sample included 100 cardiac patients consisting of equal number of patients referred for coronary angiogram and coronary artery bypass surgery. They completed measures of perceived social support, hospital anxiety and depression. The results revealed a significant effect of cardiac procedure on perceived social support, anxiety, and depression. Perceived social support yielded significant negative impact on anxiety and depression.     

Difficulties in auditory organization as a cause of reading backwardness? An auditory neuroscience perspective

Over 30 years ago, it was suggested that difficulties in the ‘auditory organization’ of word forms in the mental lexicon might cause reading difficulties. It was proposed that children used parameters such as rhyme and alliteration to organize word forms in the mental lexicon by acoustic similarity, and that such organization was impaired in developmental dyslexia. This literature was based on an ‘oddity’ measure of children's sensitivity to rhyme (e.g. wood, book, good) and alliteration (e.g. sun, sock, rag). The ‘oddity’ task revealed that children with dyslexia were significantly poorer at identifying the ‘odd word out’ than younger children without reading difficulties. Here we apply a novel modelling approach drawn from auditory neuroscience to study the possible sensory basis of the auditory organization of rhyming and non‐rhyming words by children. We utilize a novel Spectral‐Amplitude Modulation Phase Hierarchy (S‐AMPH) approach to analysing the spectro‐temporal structure of rhyming and non‐rhyming words, aiming to illuminate the potential acoustic cues used by children as a basis for phonological organization. The S‐AMPH model assumes that speech encoding depends on neuronal oscillatory entrainment to the amplitude modulation (AM) hierarchy in speech. Our results suggest that phonological similarity between rhyming words in the oddity task depends crucially on slow (delta band) modulations in the speech envelope. Contrary to linguistic assumptions, therefore, auditory organization by children may not depend on phonemic information for this task. Linguistically, it is assumed that ‘book’ does not rhyme with ‘wood’ and ‘good’ because the final phoneme differs. However, our auditory analysis suggests that the acoustic cues to this phonological dissimilarity depend primarily on the slower amplitude modulations in the speech envelope, thought to carry prosodic information. Therefore, the oddity task may help in detecting reading difficulties because phonological similarity judgements about rhyme reflect sensitivity to slow amplitude modulation patterns. Slower amplitude modulations are known to be detected less efficiently by children with dyslexia.     

The Category of Node-and-Choice Preforms for Extensive-Form Games

It would be useful to have a category of extensive-form games whose isomorphisms specify equivalences between games. Since working with entire games is too large a project for a single paper, I begin here with preforms, where a “preform” is a rooted tree together with choices and information sets. In particular, this paper first defines the category \(\mathbf {Tree}\), whose objects are “functioned trees”, which are specially designed to be incorporated into preforms. I show that \(\mathbf {Tree}\) is isomorphic to the full subcategory of \(\mathbf {Grph}\) whose objects are converging arborescences. Then the paper defines the category \(\mathbf {NCP}\), whose objects are “node-and-choice preforms”, each of which consists of a node set, a choice set, and an operator mapping node-choice pairs to nodes. I characterize the \(\mathbf {NCP}\) isomorphisms, define a forgetful functor from \(\mathbf {NCP}\) to \(\mathbf {Tree}\), and show that \(\mathbf {Tree}\) is equivalent to the full subcategory of \(\mathbf {NCP}\) whose objects are perfect-information preforms. The paper also shows that many game-theoretic entities can be derived from preforms, and that these entities are well-behaved with respect to \(\mathbf {NCP}\) morphisms and isomorphisms.     

“Looking for Work But Nothing Seems to Work”: The Job Search Strategies of Internationally Trained Engineers in Canada

This exploratory mixed-method study focussed on the experiences of internationally trained engineers in looking for and finding suitable employment in Canada. An online survey was conducted with 309 internationally trained engineers. The internationally trained engineers used a range of job search strategies to look for suitable employment in the engineering field, often with little success. Those respondents who had secured jobs in the engineering profession were significantly more likely to have been referred by another employer (p?=?0.05) and less likely to have placed or responded to an advertisement in the newspaper (p?<?0.05) than those who did not hold jobs in the engineering profession. No significant differences were seen between these two groups regarding other job search strategies used. In-depth qualitative interviews were conducted with 20 of the survey respondents, and this paper details the diverse strategies used by these participants to find suitable employment. The findings of the study emphasise the role of systemic-level barriers in the job search experience of internationally trained engineers.     

Tyrosine ameliorates heat induced delay in event related potential P300 and contingent negative variation

The efficacy of tyrosine, a catecholamine precursor, as a countermeasure in the reduction of cognitive decline during heat exposure (HE) using event-related potential P300, and contingent negative variation (CNV) was evaluated. Ten healthy males, age 20–30 years participated in the study. Volunteers received placebo or tyrosine (6.5 g) 90 min prior to HE (1.5 h in 45 °C + 30% RH). P300 latency was significantly increased (p < 0.01) during exposure with placebo, which was reduced significantly (p < 0.01) after tyrosine supplementation. There was an increase in CNV M100 latency (p < 0.05) and reaction time (p < 0.01) and decrease in M100 amplitude (p < 0.01) during HE with placebo, which returns to near normal level with the tyrosine administration. A significantly higher plasma norepinephrine (p < 0.05), dopamine and epinephrine levels were detected in tyrosine supplemented group post heat exposure. HE increases the brain catecholamine activity thereby reduces the plasma norepinephrine and dopamine level leading to a reduction in cognitive performances. Tyrosine supplementation increases the catecholamine level and reduces the impairment of cognitive performance during HE.