Gluon confinement criterion in QCD

We fix exactly and uniquely the infrared structure of the full gluon propagator in QCD, not solving explicitly the corresponding dynamical equation of motion. By construction, this structure is an infinite sum over all possible severe (i.e., more singular than $1/q^2$) infrared singularities. It reflects the zero momentum modes enhancement effect in the true QCD vacuum, which is due to the self-interaction of massless gluons. It existence automatically exhibits a characteristic mass (the so-called mass gap). It is responsible for the scale of nonperturbative dynamics in the true QCD ground state. The theory of distributions, complemented by the dimensional regularization method, allows one to put the severe infrared singularities under the firm mathematical control. By an infrared renormalization of a mass gap only, the infrared structure of the full gluon propagator is exactly reduced to the simplest severe infrared singularity, the famous $(q^2)^{-2}$. Thus we have exactly established the interaction between quarks (concerning its pure gluon (i.e., nonlinear) contribution) up to its unimportant perturbative part. This also makes it possible for the first time to formulate the gluon confinement criterion and intrinsically nonperturbative phase in QCD in a manifestly gauge-invariant ways.Comment: 10 pages, no figures, no tables. Typos corrected and the clarification is intoduced. Shorten version to appear in Phys. Lett.

Comparison of spirometry criteria for the diagnosis of COPD: results from the BOLD study

To access publisher full text version of this article. Please click on the hyperlink in Additional Links fieldPublished guidelines recommend spirometry to accurately diagnose chronic obstructive pulmonary disease (COPD). However, even spirometry-based COPD prevalence estimates can vary widely. We compared properties of several spirometry-based COPD definitions using data from the international Burden of Obstructive Lung Disease (BOLD)study. 14 sites recruited population-based samples of adults aged > or =40 yrs. Procedures included standardised questionnaires and post-bronchodilator spirometry. 10,001 individuals provided usable data. Use of the lower limit of normal (LLN) forced expiratory volume in 1 s (FEV(1)) to forced vital capacity (FVC) ratio reduced the age-related increases in COPD prevalence that are seen among healthy never-smokers when using the fixed ratio criterion (FEV(1)/FVC <0.7) recommended by the Global Initiative for Chronic Obstructive Lung Disease. The added requirement of an FEV(1) either <80% predicted or below the LLN further reduced age-related increases and also led to the least site-to-site variability in prevalence estimates after adjusting for potential confounders. Use of the FEV(1)/FEV(6) ratio in place of the FEV(1)/FVC yielded similar prevalence estimates. Use of the FEV(1)/FV

Shy children's understanding of irony: Better comprehension does not always mean better socioemotional functioning

This is the peer reviewed version of the following article: Mewhort-Buist, T. A., & Nilsen, E. S., (2019). Shy children’s understanding of irony: Better comprehension does not always mean better socioemotional functioning. Infant and Child Development, 28(3), e2131. https://doi.org/10.1002/icd.2131, which has been published in final form at https://doi.org/10.1002/icd.2131. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.Childhood shyness is a risk factor for negative socioemotional outcomes including loneliness and depression. Childhood shyness has also been found to relate to various aspects of pragmatic language. For instance, shyer children rate ironic criticisms (i.e., where a speaker's intended meaning is the opposite of what is literally said) as meaner than do less shy children. This study examined whether relations between shyness and socioemotional functioning (i.e., loneliness, depression, and peer experiences) in children (9–12 years old; N = 169) were moderated by irony comprehension ability. Using a series of vignettes and self-report measures, it was found that shyer children with better irony comprehension skill reported increased loneliness and depression symptoms, as well as fewer prosocial experiences with peers. Similarly, for girls, better comprehension strengthened the relationship between shyness and peer victimization. In contrast, for shy boys, better irony comprehension was associated with a reduction in peer victimization. Thus, for certain vulnerable populations, having better sociocommunicative skills may not be advantageous

Shy individuals’ interpretations of counterfactual verbal irony

This is an Accepted Manuscript of an article published by Taylor & Francis in Metaphor and Symbol on 2017-10-31, available online: http://www.tandfonline.com/https://doi.org/10.1080/10926488.2017.1384275.Counterfactual verbal irony, an evaluative form of figurative language wherein a speaker’s intended meaning is opposite to the literal meaning of his or her words, is used to serve many social goals. Despite recent calls for theoretical accounts to include the factors that influence irony interpretation, few studies have examined the individual differences that may impact verbal irony interpretation. The present study examined whether adults with elevated shyness would generate more negative interpretations of ironic statements. University students with varying degrees of shyness listened to stories (accompanied by comics) wherein one character made literal or ironic criticisms or compliments to another character. Participants then appraised each speaker’s belief and attitude. Self-reported shyness did not predict comprehension of the counterfactual nature of ironic statements. However, shyer adults rated speakers who made ironic compliments as being meaner than did adults low in shyness. Thus, while understanding that ironic speakers intended to communicate their true beliefs, shyer individuals construed the social meaning of irony more negatively. Such interpretive biases may lead shy individuals to more frequently take offense at ironic compliments and experience more negativity in social interactions.Funder 1, This work was supported by a Social Sciences and Humanities Research Council (SSHRC) Canadian Graduate Scholarship to T. Mewhort-Buist and SSHRC Insight Grant to E. Nilsen

An objective classification of condensation regimes in direct contact condensation

Intensified heat treatment, using direct contact condensation (DCC), is applied in the production of dairy products to ensure a high level of food safety. The key challenge with DCC is the fouling due to the protein reactions that limits operational efficiency and sustainability. Using a condensation regime map can improve operational decision-making. Pilot plant scale experiments were conducted for a wide range of steam mass fluxes and inlet temperatures at high and low channel pressures. High-speed images were recorded and analyzed to obtain penetration lengths and plume area. The experimental data and image analysis supplemented with temperature and pressure measurement, were processed using machine learning (ML) to develop a data driven model to predict the regime maps. The linear discriminant analysis (LDA) was found to be the most suitable model. From the ML models it was also found that the best parameters to make a condensation regime map are the steam pressure, channel pressure, subcooling temperature, water Prandtl number, and the relative velocity ratio between gas and liquid. The condensation outcomes were presented with various two-dimensional regime maps. New regime maps are proposed using the Prandtl number and velocity ratio as dimensionless parameters.</p

Energy-stable discretization of the one-dimensional two-fluid model

In this paper we present a complete framework for the energy-stable simulation of stratified incompressible flow in channels, using the one-dimensional two-fluid model. Building on earlier energy-conserving work on the basic two-fluid model, our new framework includes diffusion, friction, and surface tension. We show that surface tension can be added in an energy-conserving manner, and that diffusion and friction have a strictly dissipative effect on the energy. We then propose spatial discretizations for these terms such that a semi-discrete model is obtained that has the same conservation properties as the continuous model. Additionally, we propose a new energy-stable advective flux scheme that is energy-conserving in smooth regions of the flow and strictly dissipative where sharp gradients appear. This is obtained by combining, using flux limiters, a previously developed energy-conserving advective flux with a novel first-order upwind scheme that is shown to be strictly dissipative. The complete framework, with diffusion, surface tension, and a bounded energy, is linearly stable to short wavelength perturbations, and exhibits nonlinear damping near shocks. The model yields smoothly converging numerical solutions, even under conditions for which the basic two-fluid model is ill-posed. With our explicit expressions for the dissipation rates, we are able to attribute the nonlinear damping to the different dissipation mechanisms, and compare their effects

Staff perceptions of the success of an alternative curriculum: Skill Force

This paper describes staff perceptions of the implementation of an alternative curriculum, skill force, for disaffected pupils in the UK. The perceptions of skill force and school staff were compared based on data from questionnaires completed by 62 skill force and 84 school staff, and interviews with representative samples of each. While the data indicated that the programme had been successful in re-engaging the students with education, the improvement was more marked in relation to the skill force programme than the wider school context.<br/

Factors Influencing the Participation of Older People in Clinical Trials : Data Analysis from the MAVIS Trial

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