1,753 research outputs found

    Playing with Casimir in the vacuum sandbox

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    The Casimir effect continues to be a subject of discussion regarding its relationship, or the lack of it, with the vacuum energy of fluctuating quantum fields. In this note, we propose a Gedankenexperiment considering an imaginary process similar to a vacuum fluctuation in a typical static Casimir set up. The thought experiment leads to intriguing conclusions regarding the minimum distance between the plates when approaching the Planck scale. More specifically, it is found that distance between the plates cannot reach a value below (L/LP)2/3(L/L_P)^{2/3} Planck lengths, being LPL_P the Planck length and LL the typical lateral extension of the plates. Additional findings allow the conclusion that the approach between the two plates towards this minimum separation distance is asymptotic

    Extrinsic and intrinsic effects setting viscosity in life processes: implications for fundamental physical constants

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    Understanding the values and origin of fundamental physical constants, one of the grandest challenges in modern science, has been discussed in particle physics, astronomy and cosmology. More recently, it was realised that fundamental constants have a bio-friendly window set by life processes involving motion and flow. This window is related to intrinsic fluid properties such as energy and length scales in condensed matter set by fundamental constants. Here, we discuss important extrinsic factors governing the viscosity of complex fluids operating in life processes due to collective effects. We show that both extrinsic and intrinsic factors affecting viscosity need to be taken into account when estimating the bio-friendly range of fundamental constants from life processes, and our discussion provides a straightforward recipe for doing this. We also find that the relative role of extrinsic and intrinsic factors depends on the range of variability of these intrinsic and extrinsic factors. Remarkably, the viscosity of a complex fluid such as blood with significant extrinsic effects is not far from the intrinsic viscosity calculated using the fundamental constants only, and we discuss the reason for this in terms of dynamics of contact points between cells.Comment: arXiv admin note: text overlap with arXiv:2307.0527

    Knowledge and degree of training of Primary Education teachers in relation to ICT taught to disabled students

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    The integration of Information and Communication Technologies (ICT) into the inclusive classroom requires competent teaching staff from both the technological and pedagogical points of view. Within this context, and with the aim of looking at one of these theoretical premises, this study aimed to identify the degree of training and technological knowledge of primary school teachers in Spain with respect to the use of ICT with individuals with disabilities (functional diversity). A descriptive ex post-facto research method was used, where the sample comprised 777 teachers. An ad-hoc questionnaire was used as the data-collection instrument. The results revealed the low skill levels of the teachers with respect to the use of ICT with students with disabilities, where the level of training of the teaching staff was determined by personal (gender, age), professional (teaching experience) or educational (qualifications) variables. The findings of this study point to the need for teacher training that instructs teachers on the use of ICT in order to favour the learning and educational innovation of students with disabilities

    The metadata catalogue of the Spanish Institute of Oceanography: a tool to implement the EU Marine Strategy Framework Directive (MSFD)

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    The Spanish Institute of Oceanography (IEO-CSIC) is responsible, among other aspects, for scientific and technical advice for the Government's fisheries policy as well as for the protection and sustainability of the marine environment. Thus, the IEO-CSIC plays a key role in the implementation of the Marine Strategy Framework Directive (MSFD), an EU legislative act that seeks to achieve a good environmental status of European marine waters and protect the resource base on which sustain economic and social activities related to the sea. Under this commission, the IEO-CSIC generates a large amount of marine data characterized by its spatial dispersion during acquisition as well as by its different typology. One of the main tasks is to safeguard data and to disclose what data exists and where, how and when it has been acquired and, in addition, to provide access to that data through the collaboration with different national and international organizations. To this end, the data and metadata are subjected to quality control and formatted for integration into a national Spatial Data Infrastructure (SDI). This SDI has a GeoNetwork catalogue (http://datos.ieo.es) with ~ 2800 oceanographic campaigns. The metadata of the campaigns known as Cruise Summary Report (CSR) follow the ISO 19139, and although similar to those reported to the pan European SeaDataNet infrastructure, here they have been adapted following an XSL transformation to facilitate the data discovery to the Spanish community. CSRs constitute the parent metadata for ~ 250 layers associated with the implementation of the MSFD. Thus, the INSPIRE-compliant layers with biological, geological and physical resource data can be found through the catalogue and are linked to the corresponding map services. Finally, relevant metadata for the implementation of the MSFD are harvested in other national infrastructures, as the InfoMar catalogue (http://www.infomar.miteco.es/), promoted by the Ministry for the Ecological Transition and the Demographic Challenge and maintained by the CEDEX

    Calidad bacteriológica del agua en playas de Valparaíso y Viña del Mar. III contaminación ambiental

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    Se determina la contaminación microbiológica del agua de mar. en las playas más importantes de la Bahía de Valparaíso utilizando indicadores bacterianos.Coliformes totales y coliformes fecales se utilizaron como indicadores siguiendo los procedimientos de “Standard Methods”Se realiza una comparación de las técnicas de enumeración entre la fermentación de tubos múltiples y la técnica de filtración por membrana.Los resultados son expresados como media geométricas, para cada una de las estaciones estudiadas.Finalmente, se discuten los resultados obtenidos y la significación que podría tener en relación a la salud pública

    A beam-beam monitoring detector for the MPD experiment at NICA

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    The Multi-Purpose Detector (MPD) is to be installed at the Nuclotron Ion Collider fAcility (NICA) of the Joint Institute for Nuclear Research (JINR). Its main goal is to study the phase diagram of the strongly interacting matter produced in heavy-ion collisions. These studies, while providing insight into the physics of heavy-ion collisions, are relevant for improving our understanding of the evolution of the early Universe and the formation of neutron stars. In order to extend the MPD trigger capabilities, we propose to include a high granularity beam-beam monitoring detector (BE-BE) to provide a level-0 trigger signal with an expected time resolution of 30 ps. This new detector will improve the determination of the reaction plane by the MPD experiment, a key measurement for flow studies that provides physics insight into the early stages of the reaction. In this work, we use simulated Au+Au collisions at NICA energies to show the potential of such a detector to determine the event plane resolution, providing further redundancy to the detectors originally considered for this purpose namely, the Fast Forward Detector (FFD) and the Hadron Calorimeter (HCAL). We also show our results for the time resolution studies of two prototype cells carried out at the T10 beam line at the CERN PS complex.Comment: 16 pages, 12 figures. Updated to published version with added comments and correction

    Linear Collider Test of a Neutrinoless Double Beta Decay Mechanism in left-right Symmetric Theories

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    There are various diagrams leading to neutrinoless double beta decay in left-right symmetric theories based on the gauge group SU(2)_L x SU(2)_R. All can in principle be tested at a linear collider running in electron-electron mode. We argue that the so-called lambda-diagram is the most promising one. Taking the current limit on this diagram from double beta decay experiments, we evaluate the relevant cross section e e to W_L W_R, where W_L is the Standard Model W-boson and W_R the one from SU(2)_R. It is observable if the life-time of double beta decay and the mass of the W_R are close to current limits. Beam polarization effects and the high-energy behaviour of the cross section are also analyzed.Comment: 17 pages, 6 figures. v2: minor changes, references added, to be published in EPJ

    Left-right symmetry at LHC and precise 1-loop low energy data

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    Despite many tests, even the Minimal Manifest Left-Right Symmetric Model (MLRSM) has never been ultimately confirmed or falsified. LHC gives a new possibility to test directly the most conservative version of left-right symmetric models at so far not reachable energy scales. If we take into account precise limits on the model which come from low energy processes, like the muon decay, possible LHC signals are strongly limited through the correlations of parameters among heavy neutrinos, heavy gauge bosons and heavy Higgs particles. To illustrate the situation in the context of LHC, we consider the "golden" process ppe+Npp \to e^+ N. For instance, in a case of degenerate heavy neutrinos and heavy Higgs masses at 15 TeV (in agreement with FCNC bounds) we get σ(ppe+N)>10\sigma(pp \to e^+ N)>10 fb at s=14\sqrt{s}=14 TeV which is consistent with muon decay data for a very limited W2W_2 masses in the range (3008 GeV, 3040 GeV). Without restrictions coming from the muon data, W2W_2 masses would be in the range (1.0 TeV, 3.5 TeV). Influence of heavy Higgs particles themselves on the considered LHC process is negligible (the same is true for the light, SM neutral Higgs scalar analog). In the paper decay modes of the right-handed heavy gauge bosons and heavy neutrinos are also discussed. Both scenarios with typical see-saw light-heavy neutrino mixings and the mixings which are independent of heavy neutrino masses are considered. In the second case heavy neutrino decays to the heavy charged gauge bosons not necessarily dominate over decay modes which include only light, SM-like particles.Comment: 16 pages, 10 figs, KL-KS and new ATLAS limits taken into accoun

    Promoting FAIRness in marine data at Centro Nacional Instituto Español de Oceanografía

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    The Spanish Institute of Oceanography is responsible, among other aspects, for scienti c and technical advice for the Government's sheries policy as well as for the protection and sustainability of the marine environment. In this task, it generates a large amount of oceanographic data characterized by its spatial dispersion during acquisition as well as by its di erent typology. The purpose of both the National Oceanographic Data Center and the GIS team is to safeguard data and to disclose what data exists and where, how and when it has been acquired and, in addition, to provide access to that data through the collaboration with di erent international data infrastructures like EMODnet or SeaDataNet. To this end, the data and metadata are subjected to quality control and formatted for integration into a national Spatial Data Infrastructure (SDI). This SDI has a GeoNetwork catalogue with ~ 1750 oceanographic campaigns, together with (meta)data and services that are continuously being revised and incorporated. All this with the ultimate goal of making the data increasingly FAIR

    Socioeconomic differentials in the immediate mortality effects of the national Irish smoking ban

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    This article has been made available through the Brunel Open Access Publishing Fund.Background: Consistent evidence has demonstrated that smoking ban policies save lives, but impacts on health inequalities are uncertain as few studies have assessed post-ban effects by socioeconomic status (SES) and findings have been inconsistent. The aim of this study was to assess the effects of the national Irish smoking ban on ischemic heart disease (IHD), stroke, and chronic obstructive pulmonary disease (COPD) mortality by discrete and composite SES indicators to determine impacts on inequalities. Methods: Census data were used to assign frequencies of structural and material SES indicators to 34 local authorities across Ireland with a 2000–2010 study period. Discrete indicators were jointly analysed through principal component analysis to generate a composite index, with sensitivity analyses conducted by varying the included indicators. Poisson regression with interrupted time-series analysis was conducted to examine monthly age and gender-standardised mortality rates in the Irish population, ages ≥35 years, stratified by tertiles of SES indicators. All models were adjusted for time trend, season, influenza, and smoking prevalence. Results: Post-ban mortality reductions by structural SES indicators were concentrated in the most deprived tertile for all causes of death, while reductions by material SES indicators were more equitable across SES tertiles. The composite indices mirrored the results of the discrete indicators, demonstrating that post-ban mortality decreases were either greater or similar in the most deprived when compared to the least deprived for all causes of death. Conclusions: Overall findings indicated that the national Irish smoking ban reduced inequalities in smoking-related mortality. Due to the higher rates of smoking-related mortality in the most deprived group, even equitable reductions across SES tertiles resulted in decreases in inequalities. The choice of SES indicator was influential in the measurement of effects, underscoring that a differentiated analytical approach aided in understanding the complexities in which structural and material factors influence mortality
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