393 research outputs found

    The role of forcing and eddy viscosity variation on the log-layer mismatch observed in wall-modeled large-eddy simulations

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    We investigate the role of eddy viscosity variation and the effect of zonal enforcement of the mass flow rate on the log-layer mismatch problem observed in turbulent channel flows. An analysis of the mean momentum balance shows that it lacks a degree-of-freedom (DOF) when eddy viscosity is large, and the mean velocity conforms to an incorrect profile. Zonal enforcement of the target flow rate introduces an additional degree-of-freedom to the mean momentum balance, similar to an external stochastic forcing term, leading to a significant reduction in the log-layer mismatch. We simulate turbulent channel flows at friction Reynolds numbers of 2000 and 5200 on coarse meshes that do not resolve the viscous sublayer. The second-order turbulence statistics agree well with the direct numerical simulation benchmark data when results are normalized by the velocity scale extracted from the filtered velocity field. Zonal enforcement of the flow rate also led to significant improvements in skin friction coefficients

    Increasing compliance with wearing a medical device in children with autism

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    Health professionals often recommend the use of medical devices to assess the health, monitor the well-being, or improve the quality of life of their patients. Children with autism may present challenges in these situations as their sensory peculiarities may increase refusals to wear such devices. To address this issue, we systematically replicated prior research by examining the effects of differential reinforcement of other behavior (DRO) to increase compliance with wearing a heart rate monitor in 2 children with autism. The intervention increased compliance to 100% for both participants when an edible reinforcer was delivered every 90 s. The results indicate that DRO does not require the implementation of extinction to increase compliance with wearing a medical device. More research is needed to examine whether the reinforcement schedule can be further thinned

    Towards a framework for critical citizenship education

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    Increasingly countries around the world are promoting forms of "critical" citizenship in the planned curricula of schools. However, the intended meaning behind this term varies markedly and can range from a set of creative and technical skills under the label "critical thinking" to a desire to encourage engagement, action and political emancipation, often labelled "critical pedagogy". This paper distinguishes these manifestations of the "critical" and, based on an analysis of the prevailing models of critical pedagogy and citizenship education, develops a conceptual framework for analysing and comparing the nature of critical citizenship

    Altered topology of the functional speech production network in non-fluent/agrammatic variant of PPA

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    Non-fluent/agrammatic primary progressive aphasia (nfvPPA) is caused by neuro-degeneration within the left fronto-insular speech and language production network (SPN). Graph theory is a branch of mathematics that studies network architecture (topology) by quantifying features based on its elements (nodes and connections). This approach has been recently applied to neuroimaging data to explore the complex architecture of the brain connectome, though few studies have exploited this technique in PPA. Here, we used graph theory on functional MRI resting state data from a group of 20 nfvPPA patients and 20 matched controls to investigate topological changes in response to focal neuro-degeneration. We hypothesized that changes in the network architecture would be specific to the affected SPN in nfvPPA, while preserved in the spared default mode network (DMN). Topological configuration was quantified by hub location and global network metrics. Our findings showed a less efficiently wired and less optimally clustered SPN, while no changes were detected in the DMN. The SPN in the nfvPPA group showed a loss of hubs in the left fronto-parietal-temporal area and new critical nodes in the anterior left inferior-frontal and right frontal regions. Behaviorally, speech production score and rule violation errors correlated with the strength of functional connectivity of the left (lost) and right (new) regions respectively. This study shows that focal neurodegeneration within the SPN in nfvPPA is associated with network-specific topological alterations, with the loss and gain of crucial hubs and decreased global efficiency that were better accounted for through functional rather than structural changes. These findings support the hypothesis of selective network vulnerability in nfvPPA and may offer biomarkers for future behavioral intervention

    Salt Stress Induced Variation in DNA Methylation Pattern and Its Influence on Gene Expression in Contrasting Rice Genotypes

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    BACKGROUND: Salinity is a major environmental factor limiting productivity of crop plants including rice in which wide range of natural variability exists. Although recent evidences implicate epigenetic mechanisms for modulating the gene expression in plants under environmental stresses, epigenetic changes and their functional consequences under salinity stress in rice are underexplored. DNA methylation is one of the epigenetic mechanisms regulating gene expression in plant's responses to environmental stresses. Better understanding of epigenetic regulation of plant growth and response to environmental stresses may create novel heritable variation for crop improvement. METHODOLOGY/PRINCIPAL FINDINGS: Methylation sensitive amplification polymorphism (MSAP) technique was used to assess the effect of salt stress on extent and patterns of DNA methylation in four genotypes of rice differing in the degree of salinity tolerance. Overall, the amount of DNA methylation was more in shoot compared to root and the contribution of fully methylated loci was always more than hemi-methylated loci. Sequencing of ten randomly selected MSAP fragments indicated gene-body specific DNA methylation of retrotransposons, stress responsive genes, and chromatin modification genes, distributed on different rice chromosomes. Bisulphite sequencing and quantitative RT-PCR analysis of selected MSAP loci showed that cytosine methylation changes under salinity as well as gene expression varied with genotypes and tissue types irrespective of the level of salinity tolerance of rice genotypes. CONCLUSIONS/SIGNIFICANCE: The gene body methylation may have an important role in regulating gene expression in organ and genotype specific manner under salinity stress. Association between salt tolerance and methylation changes observed in some cases suggested that many methylation changes are not "directed". The natural genetic variation for salt tolerance observed in rice germplasm may be independent of the extent and pattern of DNA methylation which may have been induced by abiotic stress followed by accumulation through the natural selection process

    An Evaluation of Parent Preference for Prompting Procedures

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    Parent participation in intervention can enhance intervention efficacy and promote generalization of skills across settings. Thus, parents should be trained to implement behavioral interventions. The purpose of the current investigation was to evaluate parent preference for and acceptability of 3 commonly used prompting procedures. We trained parents of children with disabilities to use 3 empirically validated prompting strategies (i.e., least‐to‐most, most‐to‐least, and a progressive‐prompt delay). Once the parent reached the mastery criteria with each prompting procedure, we evaluated his/her preference for each of the procedures using a concurrent‐chains arrangement. We also measured treatment acceptability of all procedures throughout the study. All participants met the mastery criteria for each of the prompting procedures and showed a preference for least‐to‐most prompting. Results suggest parents\u27 acceptability of procedures prior to training were different than posttraining/post‐child practice. In addition, acceptability rating scores obtained at the end of the investigation corresponded to preference of intervention during the concurrent‐chains arrangement. The results demonstrate the benefits of objective measures for studying preference for behavioral, skill‐acquisition procedures

    How is the New Public Management applied in the occupational health care system? - decision-makers' and OH personnel's views in Finland

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    <p>Abstract</p> <p>Background</p> <p>In many countries occupational health care system is in change. Occupational health studies are mainly focused on occupational health substance and content. This study offers new perspectives on municipal OHS and its operations from management perspective.</p> <p>Aim</p> <p>The aim of this study is to analyse how New Public Management (NPM) doctrines are applied in the Finnish occupational health care system (OHS). The main focus is to describe and compare the views of decision-makers' and OH workers within the framework of NPM.</p> <p>Methods</p> <p>The data were collected by semi-structured interviews from 17 municipal decision-makers' and 26 municipal OH workers. Data was analyzed by examining coded data in a theory-driven way according to Hood's doctrine of NPM.</p> <p>Results</p> <p>The doctrines were not as compatible with the OH personnel view as with the decision-makers' view. Decision-makers and OH personnel highlighted the strict criteria required for operation evaluation. Moreover, decision-makers strongly accentuated professional management in the public sector and the reorganization of public sector units. These were not equally relevant in OH personnel views. In OH personnel views, other doctrines (more attention to performance and accomplishments, emphasizing and augmentation of the competition and better control of public expense and means test) were not similarly in evidence, only weak evidence was observed when their importance viewed as medium by decision-makers. Neither of the respondents group kept the doctrine of management models of the private sector relevant.</p> <p>Conclusions</p> <p>The NPM and Hoods doctrine fitted well with OH research. The doctrine brought out view differences and similarities between decision-makers and OH personnel. For example, policymakers highlighted more strongly the structural change by emphasizing professional management compared to OH personnel. The need for reorganization of municipal OH, regardless of different operational preconditions, was obvious for both decision-makers and OH personnel. The adaptation of more clarify management to a municipal context is not trouble-free. The municipality systemic structure, complex operational environment, and reconciliation of political and officer authority set challenges to management of municipalities.</p

    Evolution of metabolic divergence in <i>Pseudomonas aeruginosa</i> during long-term infection facilitates a proto-cooperative interspecies interaction

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    The effect of polymicrobial interactions on pathogen physiology and how it can act either to limit pathogen colonization or to potentiate pathogen expansion and virulence are not well understood. Pseudomonas aeruginosa and Staphylococcus aureus are opportunistic pathogens commonly found together in polymicrobial human infections. However, we have previously shown that the interactions between these two bacterial species are strain dependent. Whereas P. aeruginosa PAO1, a commonly used laboratory strain, effectively suppressed S. aureus growth, we observed a commensal-like interaction between the human host-adapted strain, DK2-P2M24-2003, and S. aureus. In this study, characterization by matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) imaging mass spectrometry (IMS) and mass spectral (MS) molecular networking revealed a significant metabolic divergence between P. aeruginosa PAO1 and DK2-P2M24-2003, which comprised several virulence factors and signaling 4-hydroxy-2-alkylquinoline (HAQ) molecules. Strikingly, a further modulation of the HAQ profile was observed in DK2-P2M24-2003 during interaction with S. aureus, resulting in an area with thickened colony morphology at the P. aeruginosa–S. aureus interface. In addition, we found an HAQ-mediated protection of S. aureus by DK2-P2M24-2003 from the killing effect of tobramycin. Our findings suggest a model where the metabolic divergence manifested in human host-adapted P. aeruginosa is further modulated during interaction with S. aureus and facilitate a proto-cooperative P. aeruginosa–S. aureus relationship

    Need-driven dementia-compromised behavior: An alternative view of disruptive behavior

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    The disruptive behavior of persons with dementia is a problem of considerable clinical interest and growing scientific concern. This paper offers a view of these behaviors as expressions of unmet needs or goals and provides a comprehensive conceptual framework to guide further research and clinical practice. Empiricalfindings and clinical impressions related to wandering, vocalizations and aggression to support and illustrate the framework are presentedPeer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/66887/2/10.1177_153331759601100603.pd
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