459 research outputs found

    Higher physical fitness levels are associated with less language decline in healthy ageing

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    Healthy ageing is associated with decline in cognitive abilities such as language. Aerobic fitness has been shown to ameliorate decline in some cognitive domains, but the potential benefits for language have not been examined. In a cross-sectional sample, we investigated the relationship between aerobic fitness and tip-of-the-tongue states. These are among the most frequent cognitive failures in healthy older adults and occur when a speaker knows a word but is unable to produce it. We found that healthy older adults indeed experience more tip-of-the-tongue states than young adults. Importantly, higher aerobic fitness levels decrease the probability of experiencing tip-of-the-tongue states in healthy older adults. Fitness-related differences in word finding abilities are observed over and above effects of age. This is the first demonstration of a link between aerobic fitness and language functioning in healthy older adults

    “Natural” stress patterns and dependencies between edge alignment and quantity sensitivity

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    We conducted an artificial language learning experiment to study learning asymmetries that might reveal latent preferences relating to, and any dependencies between, the edge alignment and quantity sensitivity (QS) parameters in stress patterning. We used a poverty of the stimulus approach to teach American English speakers an unbounded QS stress rule (stress a single CV: syllable) and either a left- or right-aligning QI rule if only light syllables were present. Forms with two CV: syllables were withheld in the learning phase and added in the test phase, forcing participants to choose between left- and right-aligning options for the QS rule. Participants learned the left- and right-edge QI rules equally well, and also the basic QS rule. Response patterns for words with two CV: syllables suggest biases favoring a left-aligning QS rule with a left-edge QI default. Our results also suggest that a left-aligning QS pattern with a rightedge QI default was least favored. We argue that stress patterns shown to be preferred based on evidence from ease-of-learning and participants’ untrained generalizations can be considered more natural than less favored opposing patterns. We suggest that cognitive biases revealed by artificial stress learning studies may have contributed to shaping stress typology.publishedVersio

    Outcomes of primary percutaneous coronary intervention for patients with previous coronary artery bypass grafting presenting with STsegment elevation myocardial infarction

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    BACKGROUND: There are limited data on outcomes of patients with previous coronary artery bypass grafting (CABG) presenting acutely as ST-segment elevation myocardial infarction (STEMI) and undergoing primary percutaneous coronary intervention (PPCI). OBJECTIVES: To compare outcomes in STEMI patients undergoing PPCI with or without previous CABG surgery. METHODS: An all-comer single-centre observational registry from a cardiothoracic centre in UK. All consecutive patients presenting for PPCI between 2007 and 2012 were included. Electronic records were used to extract relevant information. Mortality data were obtained from the Office of National Statistics. Overall median follow-up period was 1.7 years (intraquartile range 0.9-2.5). RESULTS: Complete data were available for 2133 (97%) patients. 47-patients had previous history of CABG. Out of these, the infarct related artery (IRA) was native vessel in 22 and graft in 25 patients. Post re-vascularization TIMI flow was inferior in CABG cohort (<TIMI 3 flow in 17% vs. 10%, p=0.012) and they were less likely to achieve acute reperfusion (TIMI 0 in 9% vs. 3%, p=0012). In-hospital-mortality was not different in both groups (2%vs.4%, p=0.23). 30-day (HR 0.54; 95%CI 0.17-1.73; P=0.301), 1-year-mortality (HR 0.77; 95%CI 0.31-1.87; P=0.56) and over a median follow-up of 1.7 years (HR 1.1; 95%CI 0.54-2.27; P=0.79) were also not different. CONCLUSION: Patients presenting with STEMI to PPCI service with history of CABG are less likely to achieve acute reperfusion and have worse angiographic outcomes. Post PPCI, the prior CABG patients do not seem to have worse shortterm and long-term prognosis

    Structural investigation of MOVPE-Grown GaAs on Ge by X-ray techniques

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    The selection of appropriate characterisation methodologies is vital for analysing and comprehending the sources of defects and their influence on the properties of heteroepitaxially grown III-V layers. In this work we investigate the structural properties of GaAs layers grown by Metal-Organic Vapour Phase Epitaxy (MOVPE) on Ge substrates – (100) with 6⁰ offset towards – under various growth conditions. Synchrotron X-ray topography (SXRT) is employed to investigate the nature of extended linear defects formed in GaAs epilayers. Other X-ray techniques, such as reciprocal space mapping (RSM) and triple axis ω-scans of (00l)-reflections (l = 2, 4, 6) are used to quantify the degree of relaxation and presence of antiphase domains (APDs) in the GaAs crystals. The surface roughness is found to be closely related to the size of APDs formed at the GaAs/Ge heterointerface, as confirmed by X-ray diffraction (XRD), as well as atomic force microscopy (AFM), and transmission electron microscopy (TEM)

    Structural investigation of MOVPE-Grown GaAs on Ge by X-ray techniques

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    The selection of appropriate characterisation methodologies is vital for analysing and comprehending the sources of defects and their influence on the properties of heteroepitaxially grown III-V layers. In this work we investigate the structural properties of GaAs layers grown by Metal-Organic Vapour Phase Epitaxy (MOVPE) on Ge substrates – (100) with 6⁰ offset towards – under various growth conditions. Synchrotron X-ray topography (SXRT) is employed to investigate the nature of extended linear defects formed in GaAs epilayers. Other X-ray techniques, such as reciprocal space mapping (RSM) and triple axis ω-scans of (00l)-reflections (l = 2, 4, 6) are used to quantify the degree of relaxation and presence of antiphase domains (APDs) in the GaAs crystals. The surface roughness is found to be closely related to the size of APDs formed at the GaAs/Ge heterointerface, as confirmed by X-ray diffraction (XRD), as well as atomic force microscopy (AFM), and transmission electron microscopy (TEM)

    Thiosemicarbazones active against Clostridium difficile

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    A set of closely related furylidene thiosemicarbazones was prepared and screened against various clinically important Gram-positive bacteria. One compound containing an ethylene spacer and a 5-nitrofuryl group was found to have promising activity against Clostridium difficile

    The relationship between language production and verbal short-term memory: The role of stress grouping

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    This study investigates the influence of stress grouping on verbal short-term memory (STM). English speakers show a preference to combine syllables into trochaic groups, both lexically and in continuous speech. In two serial recall experiments, auditory lists of nonsense syllables were presented with either trochaic (STRONG-weak) or iambic (weak-STRONG) stress patterns, or in monotone. The acoustic correlates that carry stress were also manipulated in order to examine the relationship between input and output processes during recall. In Experiment 1, stressed and unstressed syllables differed in intensity and pitch but were matched for spoken duration. Significantly more syllables were recalled in the trochaic stress pattern condition than in the iambic and monotone conditions, which did not differ. In Experiment 2, spoken duration and pitch were manipulated but intensity was held constant. No effects of stress grouping were observed, suggesting that intensity is a critical acoustic factor for trochaic grouping. Acoustic analyses demonstrated that speech output was not identical to the auditory input, but that participants generated correct stress patterns by manipulating acoustic correlates in the same way in both experiments. These data challenge the idea of a language-independent STM store and support the notion of separable phonological input and output processes

    Transcriptional analysis of temporal gene expression in germinating Clostridium difficile 630 endospores.

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    Clostridium difficile is the leading cause of hospital acquired diarrhoea in industrialised countries. Under conditions that are not favourable for growth, the pathogen produces metabolically dormant endospores via asymmetric cell division. These are extremely resistant to both chemical and physical stress and provide the mechanism by which C. difficile can evade the potentially fatal consequences of exposure to heat, oxygen, alcohol, and certain disinfectants. Spores are the primary infective agent and must germinate to allow for vegetative cell growth and toxin production. While spore germination in Bacillus is well understood, little is known about C. difficile germination and outgrowth. Here we use genome-wide transcriptional analysis to elucidate the temporal gene expression patterns in C. difficile 630 endospore germination. We have optimized methods for large scale production and purification of spores. The germination characteristics of purified spores have been characterized and RNA extraction protocols have been optimized. Gene expression was highly dynamic during germination and outgrowth, and was found to involve a large number of genes. Using this genome-wide, microarray approach we have identified 511 genes that are significantly up- or down-regulated during C. difficile germination (p≤0.01). A number of functional groups of genes appeared to be co-regulated. These included transport, protein synthesis and secretion, motility and chemotaxis as well as cell wall biogenesis. These data give insight into how C. difficile re-establishes its metabolism, re-builds the basic structures of the vegetative cell and resumes growth
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