Fully three dimensional breather solitons can be created using Feshbach resonance

We investigate the stability properties of breather solitons in a three-dimensional Bose-Einstein Condensate with Feshbach Resonance Management of the scattering length and con ned only by a one dimensional optical lattice. We compare regions of stability in parameter space obtained from a fully 3D analysis with those from a quasi two-dimensional treatment. For moderate con nement we discover a new island of stability in the 3D case, not present in the quasi 2D treatment. Stable solutions from this region have nontrivial dynamics in the lattice direction, hence they describe fully 3D breather solitons. We demonstrate these solutions in direct numerical simulations and outline a possible way of creating robust 3D solitons in experiments in a Bose Einstein Condensate in a one-dimensional lattice. We point other possible applications.Comment: 4 pages, 4 figures; accepted to Physical Review Letter

Identifying influential spreaders and efficiently estimating infection numbers in epidemic models: a walk counting approach

We introduce a new method to efficiently approximate the number of infections resulting from a given initially-infected node in a network of susceptible individuals. Our approach is based on counting the number of possible infection walks of various lengths to each other node in the network. We analytically study the properties of our method, in particular demonstrating different forms for SIS and SIR disease spreading (e.g. under the SIR model our method counts self-avoiding walks). In comparison to existing methods to infer the spreading efficiency of different nodes in the network (based on degree, k-shell decomposition analysis and different centrality measures), our method directly considers the spreading process and, as such, is unique in providing estimation of actual numbers of infections. Crucially, in simulating infections on various real-world networks with the SIR model, we show that our walks-based method improves the inference of effectiveness of nodes over a wide range of infection rates compared to existing methods. We also analyse the trade-off between estimate accuracy and computational cost, showing that the better accuracy here can still be obtained at a comparable computational cost to other methods.Comment: 6 page

High Intensity Interval Training (HIIT) as a Potential Countermeasure for Phenotypic Characteristics of Sarcopenia: A Scoping Review

Background: Sarcopenia is defined as a progressive and generalized loss of skeletal muscle quantity and function associated predominantly with aging. Physical activity appears the most promising intervention to attenuate sarcopenia, yet physical activity guidelines are rarely met. In recent years high intensity interval training (HIIT) has garnered interested in athletic populations, clinical populations, and general population alike. There is emerging evidence of the efficacy of HIIT in the young old (i.e. seventh decade of life), yet data concerning the oldest old (i.e., ninth decade of life onwards), and those diagnosed with sarcopenic are sparse. Objectives: In this scoping review of the literature, we aggregated information regarding HIIT as a potential intervention to attenuate phenotypic characteristics of sarcopenia. Eligibility Criteria: Original investigations concerning the impact of HIIT on muscle function, muscle quantity or quality, and physical performance in older individuals (mean age ≥60 years of age) were considered. Sources of Evidence: Five electronic databases (Medline, EMBASE, Web of Science, Scopus, and the Cochrane Central Register of Controlled Trials [CENTRAL]) were searched. Methods: A scoping review was conducted using the Arksey and O'Malley methodological framework (2005). Review selection and characterization were performed by two independent reviewers using pretested forms. Results: Authors reviewed 1,063 titles and abstracts for inclusion with 74 selected for full text review. Thirty-two studies were analyzed. Twenty-seven studies had a mean participant age in the 60s, two in the 70s, and three in the 80s. There were 20 studies which examined the effect of HIIT on muscle function, 22 which examined muscle quantity, and 12 which examined physical performance. HIIT was generally effective in Improving muscle function and physical performance compared to non-exercised controls, moderate intensity continuous training, or pre-HIIT (study design-dependent), with more ambiguity concerning muscle quantity. Conclusions: Most studies presented herein utilized outcome measures defined by the European Working Group on Sarcopenia in Older People (EWGSOP). However, there are too few studies investigating any form of HIIT in the oldest old (i.e., ≥80 years of age), or those already sarcopenic. Therefore, more intervention studies are needed in this population

SCOOTER: A compact and scalable dynamic labeling scheme for XML updates

Although dynamic labeling schemes for XML have been the focus of recent research activity, there are significant challenges still to be overcome. In particular, though there are labeling schemes that ensure a compact label representation when creating an XML document, when the document is subject to repeated and arbitrary deletions and insertions, the labels grow rapidly and consequently have a significant impact on query and update performance. We review the outstanding issues todate and in this paper we propose SCOOTER - a new dynamic labeling scheme for XML. The new labeling scheme can completely avoid relabeling existing labels. In particular, SCOOTER can handle frequently skewed insertions gracefully. Theoretical analysis and experimental results confirm the scalability, compact representation, efficient growth rate and performance of SCOOTER in comparison to existing dynamic labeling schemes

El rol del control personal en la función paliativa de la justificación del sistema entre la población indígena y no indígena de estudiantes peruanos

Indexación: Scopus.In this article we propose a mediation model for the association between system justification and psychological well-being (i.e., the palliative function of ideology), based on system justification theory and compensatory control theory. Specifically, we argue that endorsing system-justifying beliefs leads to increased perceived personal control, which in turn predicts higher well-being. We used a convenience sample of students from two Peruvian universities. The results showed that system justification was related to general psychological well-being and personal control. In addition, indigenous students rated lower on system justification, general psychological well-being, self-esteem and personal control. Next, we found that the association between system justification and general psychological well-being was stronger among indigenous students, and this relationship was partially mediated by personal control. In addition, we showed that the mediation model is moderated by ethnicity, so that personal control is a mediator only among non-indigenous participants. We conclude that personal control is a mechanism involved in the palliative function of ideology among this group. Finally, we discuss possible explanations for the mechanisms involved in the palliative function of ideology among low-status individuals. © 2018, © 2018 Fundacion Infancia y Aprendizaje.En este artículo se propone un modelo de mediación de las relaciones entre la justificación del sistema y el bienestar psicológico (i.e., la función paliativa de la ideología) basado en las teorías de la justificación del sistema y del control compensatorio. En concreto, se propone que la adopción de creencias justificativas del sistema produce un aumento del control personal percibido que, a su vez, predice niveles más elevados de bienestar. En este estudio se utilizó una muestra por conveniencia de estudiantes provenientes de dos universidades peruanas. Los resultados muestran que la justificación del sistema está relacionada con el bienestar psicológico general y con el control personal. Además, los estudiantes indígenas mostraron niveles más reducidos de justificación del sistema, bienestar psicológico general, autoestima y control personal. También se observó que la relación entre la justificación del sistema y el bienestar psicológico general era más fuerte entre los estudiantes indígenas y que el control personal mediaba parcialmente en esta relación. Asimismo, mostramos que la etnicidad es un factor moderador del modelo de mediación, por lo que el control personal es un mediador únicamente entre los participantes no indígenas. El estudio concluye que el control personal es un mecanismo que interviene en la función paliativa de la ideología en este grupo. Por último, se discuten posibles explicaciones de los mecanismos implicados en la función paliativa de la ideología entre individuos de estatus social bajo.https://www.tandfonline.com/doi/full/10.1080/02134748.2018.153765

Progress with air quality management in the 60 years since the UK clean air act, 1956. Lessons, failures, challenges and opportunities

© 2016 WIT Press, www.witpress.com. This paper explores the challenges, opportunities and progress made with managing air quality since the United Kingdom parliament passed the Clean Air Act, 1956. It seeks to identify the factors contributing to successful management of air quality and the factors that have acted, or continue to do so, as barriers to progress. The public health catastrophe of the 1952 London Smog created the political momentum for the 1956 Act to be passed. The nature of the contemporary air pollution challenge is reviewed in terms of the public health burden, the economic cost and the governmental response. The contemporary response is considered inadequate for the scale and intensity of the problem

Mapping ammonia risk on sensitive habitats in Ireland

© 2018 Elsevier B.V. The aim of this study was to provide a simple, cost-effective, risk-based map of terrestrial areas in Ireland where environmental quality may be at risk from atmospheric ammonia. This risk-based approach identifies Natura 2000 sites in Ireland at risk from agricultural atmospheric ammonia, collating best available data using Geographical Information Systems (GIS). In mapping ammonia risk on sensitive habitats (MARSH), the method identifies sources of ammonia, classifying them on a scale of risk from 0 to 5. These sources are subsequently summed based on a weighting determined by their contribution to national emissions divided by their potentially impacted area. A Pearson's correlation coefficient of 0.72 allows for concentrations from United Kingdom's FRAME modelling to be applied to the MARSH model, which are corrected based on recent monitoring. Applying Designation Weighted Indicators (DWI), the MARSH model predicts that 80.7, 34.3 and 5.9% of Natura 2000 sites in Ireland may exceed ambient concentrations of 1, 2, and 3 μg/m3, respectively. A Nitroindex map of Ireland based on available lichen records was also developed and is presented as part of this study. This Nitroindex was used to identify areas where impacts have already been recorded, thus informing the classification of sites “at-risk”. The combination of both the MARSH and Nitroindex models ascertains which Natura 2000 sites are most at risk, thereby providing valuable data to relevant authorities. The MARSH model acts as a first step towards screening and assessing Natura 2000 sites most at risk from atmospheric ammonia, providing a tool to demonstrate compliance with the National Emissions Ceilings Directive

Modelling high redshift Lyman α emitters

We present a new model for high redshift Lyman α emitters (LAEs) in the cosmological context which takes into account the resonant scattering of Lyα photons through expanding gas. The GALICS semi-analytic model provides us with the physical properties of a large sample of high redshift galaxies. We implement, in post-processing, a gas outflow model for each galaxy based on simple scaling arguments. The coupling with a library of numerical experiments of Lyα transfer through expanding (or static) dusty shells of gas allows us to derive the Lyα escape fraction and profile of each galaxy. Results obtained with this new approach are compared with simpler models often used in the literature. The predicted distribution of Lyα photons escape fraction shows that galaxies with a low star formation rate (SFR) have a fesc of the order of unity, suggesting that, for those objects, Lyα may be used to trace the SFR assuming a given conversion law. In galaxies forming stars intensely, the escape fraction spans the whole range from 0 to 1. The model is able to get a good match to the ultraviolet (UV) and Lyα luminosity function data at 3 < z < 5. We find that we are in good agreement with both the bright Lyα data and the faint LAE population observed by Rauch et al. at z= 3 whereas a simpler constant Lyαescape fraction model fails to do so. Most of the Lyα profiles of our LAEs are redshifted by the diffusion in the expanding gas which suppresses intergalactic medium absorption and scattering. The bulk of the observed Lyα equivalent width (EW) distribution is recovered by our model, but we fail to obtain the very large values sometimes detected. Our predictions for stellar masses and UV luminosity functions of LAEs show a satisfactory agreement with observational estimates. The UV-brightest galaxies are found to show only low Lyα EWs in our model, as it is reported by many observations of high redshift LAEs. We interpret this effect as the joint consequence of old stellar populations hosted by UV-bright galaxies, and high H i column densities that we predict for these objects, which quench preferentially resonant Lyα photons via dust extinctio

The ^(54)Mn Clock and Its Implications for Cosmic Ray Propagation and Fe Isotope Studies

Radioactive ^(54)Mn suggested as a 'clock' for measuring the lifetime of heavy cosmic rays, has a poorly known β-decay half-life estimated to be in the range from ~10^5 to 10 ^7 yr. Some years ago Koch et al. concluded from measurements of the Mn/Fe ratio that a significant fraction of low-energy (<1 GeV/nucleon) ^(54)Mn produced by Fe fragmentation had decayed. Using a propagation code that includes improved fragmentation cross-sections, and recent data from HEAO 3 and a number of other spacecraft, we have reexamined the evidence for ^(54)Mn decay in cosmic rays. We conclude that present cosmic-ray data cannot establish the degree of ^(54)Mn decay, but point out that this question has important implications for studies of the ^(54)Fe abundance in cosmic-ray source material, as well as for cosmic-ray propagation studies