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The benefit received from visual information when listening to clear and degraded speech in background noise
In order to improve speech understanding in background noise, visual information is used to enhance the incoming auditory signal. This enhancement is known as the visual speech benefit. Variation in the amount of visual speech benefit that is received by participants is the focus of this research project and is examined for both clear and vocoded speech. Vocoded speech simulates the type of speech experienced by cochlear-implant users. Experiments 1 and 2 examined variation in the amount of visual speech benefit gained if the type of background noise in the speech test changed. The key results from Experiment 1 and 2 were that the visual information provided was not enough to enhance speech understanding for particularly unintelligible speech. Experiment 3 assessed change to levels of visual speech benefit if the target talker in the stimuli changed. Significant differences in intelligibility between talkers was found. The amount of visual speech benefit increased as the audio intelligibility of the target talker decreased in clear speech. Overall, therefore, it is important that consideration is given to the levels of intelligibility provided by the stimuli used in speech perception testing as this may change outcomes. Experiments 4 and 5 examined individual differences that may predict the amount of visual speech benefit gained. In Experiment 4, the significant predictors of the amount of visual speech benefit gained in clear speech were general speech perception ability, ability to detect audio and visual synchrony, and tendency towards autistic traits. The results of Experiment 5 showed that general speech perception ability and time spent looking at the mouth area measured using eye-tracking were significant predictors of the amount of visual speech benefit gained in clear speech. Individual differences between participants may therefore predict differences in speech perception and should also be considered when testing speech perception
Visual speech benefit in clear and degraded speech depends on the auditory intelligibility of the talker and the number of background talkers
Perceiving speech in background noise presents a significant challenge to listeners. Intelligibility can be improved by seeing the face of a talker. This is of particular value to hearing impaired people and users of cochlear implants. It is well known that auditory-only speech understanding depends on factors beyond audibility. How these factors impact on the audio-visual integration of speech is poorly understood. We investigated audio-visual integration when either the interfering background speech (Experiment 1) or intelligibility of the target talkers (Experiment 2) was manipulated. Clear speech was also contrasted with sine-wave vocoded speech to mimic the loss of temporal fine structure with a cochlear implant. Experiment 1 showed that for clear speech, the visual speech benefit was unaffected by the number of background talkers. For vocoded speech, a larger benefit was found when there was only one background talker. Experiment 2 showed that visual speech benefit depended upon the audio intelligibility of the talker and increased as intelligibility decreased. Degrading the speech by vocoding resulted in even greater benefit from visual speech information. A single “independent noise” signal detection theory model predicted the overall visual speech benefit in some conditions but could not predict the different levels of benefit across variations in the background or target talkers. This suggests that, similar to audio-only speech intelligibility, the integration of audio-visual speech cues may be functionally dependent on factors other than audibility and task difficulty, and that clinicians and researchers should carefully consider the characteristics of their stimuli when assessing audio-visual integration
Publishing and sharing multi-dimensional image data with OMERO
Imaging data are used in the life and biomedical sciences to measure the molecular and structural composition and dynamics of cells, tissues, and organisms. Datasets range in size from megabytes to terabytes and usually contain a combination of binary pixel data and metadata that describe the acquisition process and any derived results. The OMERO image data management platform allows users to securely share image datasets according to specific permissions levels: data can be held privately, shared with a set of colleagues, or made available via a public URL. Users control access by assigning data to specific Groups with defined membership and access rights. OMERO’s Permission system supports simple data sharing in a lab, collaborative data analysis, and even teaching environments. OMERO software is open source and released by the OME Consortium at www.openmicroscopy.org
Lack of MEF2A Δ7aa mutation in Irish families with early onset ischaemic heart disease, a family based study
BACKGROUND: Ischaemic heart disease (IHD) is a complex disease due to the combination of environmental and genetic factors. Mutations in the MEF2A gene have recently been reported in patients with IHD. In particular, a 21 base pair deletion (Δ7aa) in the MEF2A gene was identified in a family with an autosomal dominant pattern of inheritance of IHD. We investigated this region of the MEF2A gene using an Irish family-based study, where affected individuals had early-onset IHD. METHODS: A total of 1494 individuals from 580 families were included (800 discordant sib-pairs and 64 parent-child trios). The Δ7aa region of the MEF2A gene was investigated based on amplicon size. RESULTS: The Δ7aa mutation was not detected in any individual. Variation in the number of CAG (glutamate) and CCG (proline) residues was detected in a nearby region. However, this was not found to be associated with IHD. CONCLUSION: The Δ7aa mutation was not detected in any individual within the study population and is unlikely to play a significant role in the development of IHD in Ireland. Using family-based tests of association the number of tri-nucleotide repeats in a nearby region of the MEF2A gene was not associated with IHD in our study group
Different degrees of malnutrition and immunological alterations according to the aetiology of cirrhosis: a prospective and sequential study
OBJECTIVES: In this work we investigated how immunological dysfunction and malnutrition interact in alcoholic and viral aetiologies of cirrhosis. METHODS: To investigate the matter, 77 cirrhotic patients divided in three aetiologies [Alcohol, HCV and Alcohol + HCV) and 32 controls were prospectivelly and sequentially studied. Parameters of humoral immunity (Components 3 and 4 of seric complement and immunoglobulins A M, G and E) and of cellular immunity (total leukocytes and lymphocytes in peripheral blood, T lymphocytes subpopulations, CD4+ and CD8+, CD4+/CD8+ ratio and intradermic tests of delayed hypersensitivity), as well as nutrititional parameters: anthropometric measures, serum albumin and transferrin were evaluated. RESULTS: Multiple statistical comparisons showed that IgM was higher in HCV group; IgG was significantly elevated in both HCV and Alcohol + HCV, whereas for the Alcohol group, IgE was found at higher titles. The analysis of T- lymphocytes subpopulations showed no aetiologic differences, but intradermic tests of delayed hypersensitivity did show greater frequency of anergy in the Alcohol group. For anthropometric parameters, the Alcohol +HCV group displayed the lowest triceps skinfold whereas creatinine – height index evaluation was more preserved in the HCV group. Body mass index, arm muscle area and arm fat area showed that differently from alcohol group, the HCV group was similar to control. CONCLUSION: Significant differences were found among the main aetiologies of cirrhosis concerning immunological alterations and nutritional status: better nutrition and worse immunology for HCV and vice-versa for alcohol
Phosphoenolpyruvate carboxylase dentified as a key enzyme in erythrocytic Plasmodium falciparum carbon metabolism
Phospoenolpyruvate carboxylase (PEPC) is absent from humans but encoded in thePlasmodium falciparum genome, suggesting that PEPC has a parasite-specific function. To investigate its importance in P. falciparum, we generated a pepc null mutant (D10Δpepc), which was only achievable when malate, a reduction product of oxaloacetate, was added to the growth medium. D10Δpepc had a severe growth defect in vitro, which was partially reversed by addition of malate or fumarate, suggesting that pepc may be essential in vivo. Targeted metabolomics using 13C-U-D-glucose and 13C-bicarbonate showed that the conversion of glycolytically-derived PEP into malate, fumarate, aspartate and citrate was abolished in D10Δpepc and that pentose phosphate pathway metabolites and glycerol 3-phosphate were present at increased levels. In contrast, metabolism of the carbon skeleton of 13C,15N-U-glutamine was similar in both parasite lines, although the flux was lower in D10Δpepc; it also confirmed the operation of a complete forward TCA cycle in the wild type parasite. Overall, these data confirm the CO2 fixing activity of PEPC and suggest that it provides metabolites essential for TCA cycle anaplerosis and the maintenance of cytosolic and mitochondrial redox balance. Moreover, these findings imply that PEPC may be an exploitable target for future drug discovery
Metaethics, teleosemantics and the function of moral judgements
This paper applies the theory of teleosemantics to the issue of moral content. Two versions of teleosemantics are distinguished: input-based and output-based. It is argued that applying either to the case of moral judgements generates the conclusion that such judgements have both descriptive (belief-like) and directive (desire-like) content, intimately entwined. This conclusion directly validates neither descriptivism nor expressivism, but the application of teleosemantics to moral content does leave the descriptivist with explanatory challenges which the expressivist does not face. Since teleosemantics ties content to function, the paper also offers an account of the evolutionary function of moral judgements
Photo-enhanced antinodal conductivity in the pseudogap state of high-T-c cuprates
A major challenge in understanding the cuprate superconductors is to clarify the nature of the fundamental electronic correlations that lead to the pseudogap phenomenon. Here we use ultrashort light pulses to prepare a non-thermal distribution of excitations and capture novel properties that are hidden at equilibrium. Using a broadband (0.5-2 eV) probe, we are able to track the dynamics of the dielectric function and unveil an anomalous decrease in the scattering rate of the charge carriers in a pseudogap-like region of the temperature (T) and hole-doping (p) phase diagram. In this region, delimited by a well-defined T*(neq)(p) line, the photoexcitation process triggers the evolution of antinodal excitations from gapped (localized) to delocalized quasiparticles characterized by a longer lifetime. The novel concept of photo-enhanced antinodal conductivity is naturally explained within the singleband Hubbard model, in which the short-range Coulomb repulsion leads to a k-space differentiation between nodal quasiparticles and antinodal excitations. \ua9 2014 Macmillan Publishers Limited. All rights reserved
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