545 research outputs found
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The effect of ambient sounds on decision-making and heart rate variability in autism.
Many autistic people report difficulties making decisions during everyday tasks, such as shopping. To examine the effect of sounds on decision-making, we developed a supermarket task where people watched a film shown from the shopper's perspective and were asked to make decisions between different products. The task was divided into three sections and participants completed each section in a different auditory environment: (1) no sounds, (2) non-social sounds (e.g. fridges humming) and (3) social sounds (e.g. people talking). Thirty-eight autistic and 37 neurotypical adults took part. We measured decision-making by examining how long it took to make a decision and how consistent people were with their decisions. We also measured heart rate variability because this biological response provides a measure of anxiety. After the supermarket shopping task, participants told us in their own words about their experiences. Autistic participants said that they found the non-social and social sound conditions more difficult than the no sound condition, and autistic participants found the social sound condition more negative than neurotypical participants. However, decision-making and heart rate variability were similar for autistic and neurotypical participants across the sound conditions, suggesting that these measures may not have been sensitive enough to reflect the experiences the autistic participants reported. Further research should consider alternative measures to explore the experiences reported by autistic people to help us understand which specific aspects of the environment autistic people are sensitive to. This, in turn, may enable more specific and evidence-based autism-friendly changes to be made.Anonymous donatio
Eigen-AD: Algorithmic Differentiation of the Eigen Library
In this work we present useful techniques and possible enhancements when
applying an Algorithmic Differentiation (AD) tool to the linear algebra library
Eigen using our in-house AD by overloading (AD-O) tool dco/c++ as a case study.
After outlining performance and feasibility issues when calculating derivatives
for the official Eigen release, we propose Eigen-AD, which enables different
optimization options for an AD-O tool by providing add-on modules for Eigen.
The range of features includes a better handling of expression templates for
general performance improvements, as well as implementations of symbolically
derived expressions for calculating derivatives of certain core operations. The
software design allows an AD-O tool to provide specializations to automatically
include symbolic operations and thereby keep the look and feel of plain AD by
overloading. As a showcase, dco/c++ is provided with such a module and its
significant performance improvements are validated by benchmarks.Comment: Updated with accepted version for ICCS 2020 conference proceedings.
The final authenticated publication is available online at
https://doi.org/10.1007/978-3-030-50371-0_51. See v1 for the original,
extended preprint. 14 pages, 7 figure
Application of quasi-Monte Carlo methods to PDEs with random coefficients -- an overview and tutorial
This article provides a high-level overview of some recent works on the
application of quasi-Monte Carlo (QMC) methods to PDEs with random
coefficients. It is based on an in-depth survey of a similar title by the same
authors, with an accompanying software package which is also briefly discussed
here. Embedded in this article is a step-by-step tutorial of the required
analysis for the setting known as the uniform case with first order QMC rules.
The aim of this article is to provide an easy entry point for QMC experts
wanting to start research in this direction and for PDE analysts and
practitioners wanting to tap into contemporary QMC theory and methods.Comment: arXiv admin note: text overlap with arXiv:1606.0661
Hot new directions for quasi-Monte Carlo research in step with applications
This article provides an overview of some interfaces between the theory of
quasi-Monte Carlo (QMC) methods and applications. We summarize three QMC
theoretical settings: first order QMC methods in the unit cube and in
, and higher order QMC methods in the unit cube. One important
feature is that their error bounds can be independent of the dimension
under appropriate conditions on the function spaces. Another important feature
is that good parameters for these QMC methods can be obtained by fast efficient
algorithms even when is large. We outline three different applications and
explain how they can tap into the different QMC theory. We also discuss three
cost saving strategies that can be combined with QMC in these applications.
Many of these recent QMC theory and methods are developed not in isolation, but
in close connection with applications
Ageing Intensifies the Care Needs of Adults Living with Parkinson ’s Disease and their Carers
Parkinson’s disease (PD) is the second most common neurological disorder in Australia typically affecting people over the age of 65. Few studies of people living with Parkinson’s disease have estimated current hours of home support and unmet needs. In addition no studies have been found that estimate hours of unmet need in terms of functioning or care arrangements or examined whether these estimates differ depending on the viewpoints of carers and the people living with PD whom they care for. In 2007, we surveyed the home care support needs of adults diagnosed with Parkinson’s disease in Western Australia (WA). The survey revealed that adults living with Parkinson’s disease prefer, and can be supported with, home care support services in lieu of residential care placement. As expected, required services increased as functioning decreased. In addition, unmet needs were found to be greater for those with carers irrespective of their level of functional dependency. Unmet needs for weekly services, for people that require home support services, are estimated at 38, 33, 55 and 47 min for personal care, cleaning, social support, and gardening and home maintenance, respectively. The survey also found that most carers and people living with PD agreed that current levels of different types of home care support including nursing were either adequate or insufficient; some carers preferred more services even if the people living with PD were satisfied and some people living with PD wanted more services even if their carers reported needing no extra help. Respite was used by 29 % of people living with PD with carers with two thirds wanting more opportunities for respite. Of the 71 % of people living with PD with carers who had not used respite, less than half stated that they would like to use respite. The 2007 survey was followed by interviews with a sample of survey respondents at different stages of their disorder. In the interviews, most of the people living with Parkinson’s disease commented that continuing to remain at home depended on the rate of degeneration of their disorder as well as the ability of their carers to continue to care. Most of these people and their careers were living day-to-day with a hope that enough support would be made available if and when they need it. As vocal Baby Boomers age, policymakers would do well to acknowledge the diversity of care needs for people with Parkinson’s disease and address the quantum and type of support to meet these needs
Synthesis of an ordered mesoporous carbon with graphitic characteristics and its application for dye adsorption
An ordered mesoporous carbon (OMC) was prepared by a chemical vapor deposition technique using liquid petroleum gas (LPG) as the carbon source. During synthesis, LPG was effectively adsorbed in the ordered mesopores of SBA-15 silica and converted to a graphitic carbon at 800 °C. X-ray diffraction and nitrogen adsorption/desorption data and high-resolution transmission electron microscopy (HRTEM) of the OMC confirmed its ordered mesoporous structure. The OMC was utilized as an adsorbent in the removal of dyes from aqueous solution. A commercial powder activated carbon (AC) was also investigated to obtain comparative data. The efficiency of the OMC for dye adsorption was tested using acidic dye acid orange 8 (AO8) and basic dyes methylene blue (MB) and rhodamine B (RB). The results show that adsorption was affected by the molecular size of the dye, the textural properties of carbon adsorbent and surface-dye interactions. The adsorption capacities of the OMC for acid orange 8 (AO8), methylene blue (MB) and rhodamine B (RB) were determined to be 222, 833, and 233 mg/g, respectively. The adsorption capacities of the AC for AO8, MB, and RB were determined to be 141, 313, and 185 mg/ g, respectively. The OMC demonstrated to be an excellent adsorbent for the removal of MB from wastewater.Web of Scienc
Dust in brown dwarfs and extra-solar planets IV. Assessing TiO2 and SiO nucleation for cloud formation modeling
Clouds form in atmospheres of brown dwarfs and planets. The cloud particle
formation processes are similar to the dust formation process studied in
circumstellar shells of AGB stars and in Supernovae. Cloud formation modelling
in substellar objects requires gravitational settling and element replenishment
in addition to element depletion. All processes depend on the local conditions,
and a simultaneous treatment is required. We apply new material data in order
to assess our cloud formation model results regarding the treatment of the
formation of condensation seeds. We re-address the question of the primary
nucleation species in view of new (TiO2)_N-cluster data and new SiO vapour
pressure data. We apply the density functional theory using the computational
chemistry package Gaussian 09 to derive updated thermodynamical data for
(TiO2)_N-clusters as input for our TiO2 seed formation model. We test different
nucleation treatments and their effect on the overall cloud structure by
solving a system of dust moment equations and element conservation or a
pre-scribed Drift-Phoenix atmosphere structure. Updated Gibbs free energies for
the (TiO2)_N-clusters are presented, and a slightly temperature dependent
surface tension for T=500 ... 2000K with an average value of sigma_infty =
480.6 erg 1/cm2. The TiO2-seed formation rate changes only slightly with the
updated cluster data. A considerably larger effect on the rate of seed
formation, and hence on grain size and dust number density, results from a
switch to SiO-nucleation. Despite the higher abundance of SiO over TiO2 in the
gas phase, TiO2 remains considerably more efficient in forming condensation
seeds by homogeneous nucleation followed by heterogeneous grain growth. The
paper discussed the effect on the cloud structure in more detail.Comment: accepted for publication in A&A (abstract abridged
The role of receptivity in the courtship behavior of Podocnemis erythrocephala in captivity
The courtship behavior of Podocnemis erythrocephala (Red-headed Amazon River Turtle) in captivity was studied to examine female receptivity and male response to female rejection. We observed 20 females and 39 males in 150 sessions (3–6 h/day for a total of 450 h). In 36% of the trials, there was no interaction between males and females, and 20% of the trials resulted in copulations. All males introduced into tanks approached females, and eventually there was aggression among the males. In 48% of the experiments, females also searched for or approached males. When males initially approached females, they either accepted the male’s advances (14%), rejected the male passively (38%), or rejected the male aggressively (48%). In 86% of the cases where males were rejected, 4% attempted to approach females again, and in 51% they were ultimately successful
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