The number of stimulus-onset asynchronies affects the perception of the sound-induced flash illusion in young and older adults

The sound-induced flash illusion is a multisensory illusion occurring when one flash is presented with two beeps and perceived as two flashes. Younger individuals are largely susceptible to the illusion when the stimulus onset asynchrony between the first and the second beep falls within the temporal window of integration, but the susceptibility falls dramatically outside of this short temporal range. Older individuals, in particular older adults prone to falling and/or mild cognitive impairment, show an extended susceptibility to the illusion. This suggests that they have inefficient multisensory integration, particularly in the temporal domain. In the present study, we investigated the reliability of the illusion across younger and older people, guided by the hypothesis that the experimental context, i.e., exposure to a wider or smaller number of stimulus onset asynchronies, would modify the intra-personal susceptibility to the illusion at shorter asynchronies vs. longer asynchronies, likely due to the gathering of model evidence based on Bayesian inference. We tested 22 young adults and 29 older adults and verified these hypotheses. Both groups showed higher susceptibility to the illusion when exposed to a smaller range of asynchronies, but only for longer ones, not within the 100 ms window. We discuss the theoretical implications in terms of online perceptual learning and practical implications in terms of standardisation of the experimental context when attempting to find normative values

Improving audio-visual temporal perception through training enhances beta-band activity

Multisensory integration strongly depends on the temporal proximity between two inputs. In the audio-visual domain, stimulus pairs with delays up to a few hundred milliseconds can be perceived as simultaneous and integrated into a unified percept. Previous research has shown that the size of this temporal window of integration can be narrowed by feedback-guided training on an audio-visual simultaneity judgment task. Yet, it has remained uncertain how the neural network that processes audio-visual asynchronies is affected by the training. In the present study, participants were trained on a 2-interval forced choice audio-visual simultaneity judgment task. We recorded their neural activity with magnetoencephalography in response to three different stimulus onset asynchronies (0 ms, each participant’s individual binding window, 300 ms) before, and one day following training. The Individual Window stimulus onset asynchrony condition was derived by assessing each participant’s point of subjective simultaneity. Training improved performance in both asynchronous stimulus onset conditions (300 ms, Individual Window). Furthermore, beta-band amplitude (12–30 Hz) increased from pre-compared to post-training sessions. This increase moved across central, parietal, and temporal sensors during the time window of 80–410 ms post-stimulus onset. Considering the putative role of beta oscillations in carrying feedback from higher to lower cortical areas, these findings suggest that enhanced top-down modulation of sensory processing is responsible for the improved temporal acuity after training. As beta oscillations can be assumed to also preferentially support neural communication over longer conduction delays, the widespread topography of our effect could indicate that training modulates not only processing within primary sensory cortex, but rather the communication within a large-scale network

Familiarity of objects affects susceptibility to the sound-induced flash

Audition is accepted as more reliable (thus dominant) than vision when temporal discrimination is required by the task. However, it is not known whether the characteristics of the visual stimulus, for example its familiarity to the perceiver, affect auditory dominance. In this study we manipulated familiarity of the visual stimulus in a well-established multisensory phenomenon, i.e., the sound-induced flash illusion. This illusion occurs when, for example, one brief visual stimulus (e.g., a flash) is presented in close temporal proximity with two brief sounds; participants perceive two flashes instead of one. We found that when the visual stimuli (faces or buildings) were familiar, participants were less susceptible to the illusion than when they were unfamiliar. As the illusion has been ascribed to early cross-sensory interactions between vision and audition, the present work offers behavioural evidence that high level processing of objects’ characteristics such as familiarity, affects early temporal multisensory integration. Possible mechanisms underlying the effect of familiarity are discussed

Application of fuzzy integrated FMEA with product lifetime consideration for new product development in flexible electronics industry

Purpose: the aim of this paper is to minimize the risks of new product development and shorten time-to-market, particularly for high-tech enterprise where the complexity of the product generates vast amount of failure mode. Design/methodology/approach: first, the concept of Critical Consideration Factor (CCF) is introduced based on product-specific technical characteristics, expected lifetime, and yield requirement to identify and prioritize the critical failure mode in the subsequent Failure Mode and Effect Analysis (FMEA), followed by process characterization on the high-risk failure mode and Critical Parameter Management (CPM) practice to realize a robust mass production system of the developed technology. The application on the development of advanced flexible substrate and surface finishes fabrication technique is presented. Findings: through the proposed methodology, the risk level of each potential failure mode can be accurately quantified to identify the critical variables. With process characterization, reliability of the product is ensured. Consequently, significant reduction in development resources and time-to-market can be achieved. Practical implications: the development strategy allows high tech enterprises to achieve a balanced ecosystem in which value created through adaption of new technology/product can be thoroughly captured through commercialization in a timely manner with no field failure. Originality/value: the proposed development strategy utilizes a unique approach with thorough considerations that enables high tech enterprise to deliver new product with rapid time-to-market without sacrificing product lifetime reliability, which is key to achieve competitive advantage in the highly dynamic market.Peer Reviewe

Measurements of Isoprene-Derived Organosulfates in Ambient Aerosols by Aerosol Time-of-Flight Mass Spectrometry—Part 2: Temporal Variability and Formation Mechanisms

Organosulfate species have recently gained attention for their potentially significant contribution to secondary organic aerosol (SOA); however, their temporal behavior in the ambient atmosphere has not been probed in detail. In this work, organosulfates derived from isoprene were observed in single particle mass spectra in Atlanta, GA during the 2002 Aerosol Nucleation and Characterization Experiment (ANARChE) and the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Real-time measurements revealed that the highest organosulfate concentrations occurred at night under a stable boundary layer, suggesting gas-to-particle partitioning and subsequent aqueous-phase processing of the organic precursors played key roles in their formation. Further analysis of the diurnal profile suggests possible contributions from multiple production mechanisms, including acid-catalysis and radical-initiation. This work highlights the potential for additional SOA formation pathways in biogenically influenced urban regions to enhance the organic aerosol burden

Spectral Energy Distributions of Local Luminous And Ultraluminous Infrared Galaxies

Luminous and ultraluminous infrared galaxies ((U)LIRGs) are the most extreme star forming galaxies in the universe. The local (U)LIRGs provide a unique opportunity to study their multi-wavelength properties in detail for comparison to their more numerous counterparts at high redshifts. We present common large aperture photometry at radio through X-ray wavelengths, and spectral energy distributions (SEDs) for a sample of 53 nearby LIRGs and 11 ULIRGs spanning log (LIR/Lsun) = 11.14-12.57 from the flux-limited Great Observatories All-sky LIRG Survey (GOALS). The SEDs for all objects are similar in that they show a broad, thermal stellar peak and a dominant FIR thermal dust peak, where nuLnu(60um) / nuLnu(V) increases from ~2-30 with increasing LIR. When normalized at IRAS-60um, the largest range in the luminosity ratio, R(lambda)=log[nuLnu(lambda)/nuLnu(60um)] observed over the full sample is seen in the Hard X-rays (HX=2-10 keV). A small range is found in the Radio (1.4GHz), where the mean ratio is largest. Total infrared luminosities, LIR(8-1000um), dust temperatures, and dust masses were computed from fitting thermal dust emission modified blackbodies to the mid-infrared (MIR) through submillimeter SEDs. The new results reflect an overall ~0.02 dex lower luminosity than the original IRAS values. Total stellar masses were computed by fitting stellar population synthesis models to the observed near-infrared (NIR) through ultraviolet (UV) SEDs. Mean stellar masses are found to be log(M/Msun) = 10.79+/-0.40. Star formation rates have been determined from the infrared (SFR_IR~45Msun/yr) and from the monochromatic UV luminosities (SFR_UV~1.3Msun/yr), respectively. Multiwavelength AGN indicators have be used to select putative AGN: about 60% of the ULIRGs would have been classified as an AGN by at least one of the selection criteria.Comment: 39 pages, including 12 figures and 11 tables; accepted for publication in ApJ

Metatranscriptome of human faecal microbial communities in a cohort of adult men

The gut microbiome is intimately related to human health, but it is not yet known which functional activities are driven by specific microorganisms\u27 ecological configurations or transcription. We report a large-scale investigation of 372 human faecal metatranscriptomes and 929 metagenomes from a subset of 308 men in the Health Professionals Follow-Up Study. We identified a metatranscriptomic \u27core\u27 universally transcribed over time and across participants, often by different microorganisms. In contrast to the housekeeping functions enriched in this core, a \u27variable\u27 metatranscriptome included specialized pathways that were differentially expressed both across participants and among microorganisms. Finally, longitudinal metagenomic profiles allowed ecological interaction network reconstruction, which remained stable over the six-month timespan, as did strain tracking within and between participants. These results provide an initial characterization of human faecal microbial ecology into core, subject-specific, microorganism-specific and temporally variable transcription, and they differentiate metagenomically versus metatranscriptomically informative aspects of the human faecal microbiome

Measurements of Isoprene-Derived Organosulfates in Ambient Aerosols by Aerosol Time-of-Flight Mass Spectrometry - Part 1: Single Particle Atmospheric Observations in Atlanta

Organosulfate species have recently been identified as a potentially significant class of secondary organic aerosol (SOA) species, yet little is known about their behavior in the atmosphere. In this work, organosulfates were observed in individual ambient aerosols using single particle mass spectrometry in Atlanta, GA during the 2002 Aerosol Nucleation and Characterization Experiment (ANARChE) and the 2008 August Mini-Intensive Gas and Aerosol Study (AMIGAS). Organosulfates derived from biogenically produced isoprene were detected as deprotonated molecular ions in negative-ion spectra measured by aerosol time-of-flight mass spectrometry; comparison to high-resolution mass spectrometry data obtained from filter samples corroborated the peak assignments. The size-resolved chemical composition measurements revealed that organosulfate species were mostly detected in submicrometer aerosols and across a range of aerosols from different sources, consistent with secondary reaction products. Detection of organosulfates in a large fraction of negative-ion ambient spectra − ca. 90−95% during ANARChE and ~65% of submicrometer particles in AMIGAS − highlights the ubiquity of organosulfate species in the ambient aerosols of biogenically influenced urban environments