Effective action in DSR1 quantum field theory

We present the one-loop effective action of a quantum scalar field with DSR1 space-time symmetry as a sum over field modes. The effective action has real and imaginary parts and manifest charge conjugation asymmetry, which provides an alternative theoretical setting to the study of the particle-antiparticle asymmetry in nature.Comment: 8 page

Reflectance of Polytetrafluoroethylene (PTFE) for Xenon Scintillation Light

Gaseous and liquid xenon particle detectors are being used in a number of applications including dark matter search and neutrino-less double beta decay experiments. Polytetrafluoroethylene (PTFE) is often used in these detectors both as electrical insulator and as a light reflector to improve the efficiency of detection of scintillation photons. However, xenon emits in the vacuum ultraviolet wavelength region (175 nm) where the reflecting properties of PTFE are not sufficiently known. In this work we report on measurements of PTFE reflectance, including its angular distribution, for the xenon scintillation light. Various samples of PTFE, manufactured by different processes (extruded, expanded, skived and pressed) have been studied. The data were interpreted with a physical model comprising both specular and diffuse reflections. The reflectance obtained for these samples ranges from about 47% to 66% for VUV light. Fluoropolymers, namely ETFE, FEP and PFA were also measured

Quantitative and Qualitative Evaluation of Legume Forage Species in Southern Italy

Legume herbage quality and quantity depend on genetic background to be able to sustain metabolic activity under increasingly harsh environmental conditions. Field experiments were carried out in Foggia, a southern Italian town (a typical Mediterranean location) on varieties and ecotypes of two perennial legume (sainfoin and sulla) mostly widespread in Mediterranean environments. The experiment compared irrigated and non-irrigated conditions and two different seed rates. The aim of the study was to evaluate the effect of agronomic factors on herbage production and the nutritive value of the forage. Irrigation and higher seed rate treatment increased dry matter yield in both species. The genotypes of both species differed for agronomic adaptation and in nutritive characteristics which were influenced by irrigation treatment. Crude protein (CP) contents under irrigated treatment was lower than non irrigated only in sulla. Percentages of neutral detergent fibre (NDF) and acid detergent fiber (ADF) were influenced by lower seed rate. The genotypes exploit their genetic potentiality mainly under irrigated condition in sainfoin and sulla. Lower seed rate was more suitable under non irrigated conditions. The nutritive value, in both species, was related to the dry matter production and leaf stem proportion of genotypes

Schwinger's Method for the Massive Casimir Effect

We apply to the massive scalar field a method recently proposed by Schwinger to calculate the Casimir effect. The method is applied with two different regularization schemes: the Schwinger original one by means of Poisson formula and another one by means of analytical continuation.Comment: plain TeX, 6 pages, DFTUZ-93-2

Cosmology without inflation

We propose a new cosmological paradigm in which our observed expanding phase is originated from an initially large contracting Universe that subsequently experienced a bounce. This category of models, being geodesically complete, is non-singular and horizon-free, and can be made to prevent any relevant scale to ever have been smaller than the Planck length. In this scenario, one can find new ways to solve the standard cosmological puzzles. One can also obtain scale invariant spectra for both scalar and tensor perturbations: this will be the case, for instance, if the contracting Universe is dust-dominated at the time at which large wavelength perturbations get larger than the curvature scale. We present a particular example based on a dust fluid classically contracting model, where a bounce occurs due to quantum effects, in which these features are explicit.Comment: 8 pages, no figur

A classification model for product-service offerings

Organisations have been approaching servitisation in an unstructured fashion. This is partially because there is insufficient understanding of the different types of Product-Service offerings. Therefore, a more detailed understanding of Product-Service types might advance the collective knowledge and assist organisations that are considering a servitisation strategy. Current models discuss specific aspects on the basis of few (or sometimes single) dimensions. In this paper, we develop a comprehensive model for classifying traditional and green Product-Service offerings, thus combining business and green offerings in a single model. We describe the model building process and its practical application in a case study. The model reveals the various traditional and green options available to companies and identifies how to compete between services; it allows servitisation positions to be identified such that a company may track its journey over time. Finally it fosters the introduction of innovative Product-Service Systems as promising business models to address environmental and social challenges.EPSRC, EPSRC supported the Cranfield IMRCThis is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.jclepro.2013.11.03

Recycling of textile waste by reinforcing earthy render with micro-fiber

Earth construction is worldwide spread. It is a valuable heritage to preserve because of its cultural and socio-economical relevance. Furthermore, earth construction, since it needs significantly less energy than modern construction techniques, and works with local materials, it contributes for thesustainable development. In Portugal, there is an impressive earth construction heritage that requires maintenance. Among the Portuguese traditional building techniques related to earth construction, the rammed earth, the adobe and the tabique are the most relevant ones. This work is focused on attempting to apply textile waste micro-fiber as an alternative sustainable reinforcement solution of earthy render of tabique walls. Therefore, several earthy render samples reinforced with 1% textile waste micro-fiber content were prepared and mechanically tested. The main experimental results are presented and discussed, and the main conclusions are drawn. This study also contributes for recycling a specific waste, namely short fibers from needling machines used to produce nonwoven fabrics

Chemical Evolution of the Galaxy Based on the Oscillatory Star Formation History

We model the star formation history (SFH) and the chemical evolution of the Galactic disk by combining an infall model and a limit-cycle model of the interstellar medium (ISM). Recent observations have shown that the SFH of the Galactic disk violently variates or oscillates. We model the oscillatory SFH based on the limit-cycle behavior of the fractional masses of three components of the ISM. The observed period of the oscillation ($\sim 1$ Gyr) is reproduced within the natural parameter range. This means that we can interpret the oscillatory SFH as the limit-cycle behavior of the ISM. We then test the chemical evolution of stars and gas in the framework of the limit-cycle model, since the oscillatory behavior of the SFH may cause an oscillatory evolution of the metallicity. We find however that the oscillatory behavior of metallicity is not prominent because the metallicity reflects the past integrated SFH. This indicates that the metallicity cannot be used to distinguish an oscillatory SFH from one without oscillations.Comment: 21 pages LaTeX, to appear in Ap