Inflation and Reheating in Spontaneously Generated Gravity

Inflation is studied in the context of induced gravity (IG) $\gamma \sigma^2 R$, where $R$ is the Ricci scalar, $\sigma$ a scalar field and $\gamma$ a dimensionless constant, and diverse symmetry-breaking potentials $V(\sigma)$ are considered. In particular we compared the predictions for Landau-Ginzburg (LG) and Coleman-Weinberg (CW) type potentials and their possible generalizations with the most recent data. We find that large field inflation generally leads to fewer constraints on the parameters and the shape of the potential whereas small field inflation is more problematic and, if viable, implies more constraints, in particular on the parameter $\gamma$. We also examined the reheating phase and obtained an accurate analytical solution for the dynamics of inflaton and the Hubble parameter by using a multiple scale analysis (MSA). The solutions were then used to study the average expansion of the Universe, the average equation of state for the scalar field and both the perturbative and resonant decays of the inflaton field.Comment: 15 pages, 10 figures, to be published in Phys. Rev.

STRATEGIE INNOVATIVE PER LA VALUTAZIONE DI ABUSO ALCOLICO A SCOPO FORENSE

L'abuso di alcol è un problema comune nella società; tuttavia, le capacità tecniche di valutare il consumo individuale di alcool, utilizzando biomarcatori oggettivi, sono attualmente piuttosto limitate a causa della scarsa sensibilità e specificità dei marcatori effettivamente utilizzati. Questo studio ha lo scopo di valutare l’abuso di alcool mediante la comparazione dei marcatori tradizionali con quelli di più recente introduzione, in soggetti che si sono sottoposti ad accertamenti per il rinnovo o la revisione della patente di guida. Tra i marcatori tradizionali di un consumo eccessivo di alcool troviamo la transferrina carboidrato carente (CDT). La determinazione di un metabolita non ossidativo dell'etanolo, l’Etilglucuronide (EtG) nei capelli, è stato invece proposto come nuovo marcatore con qualità superiori. Sono stati testati 133 soggetti per valutarne l’abuso alcolico, mediante l’analisi dell’EtG su matrice pilifera e della CDT su campioni di siero. Rispettivamente 1 (0,75%) e 29 (21,80%) soggetti sono risultati positivi alla CDT e all’ EtG. In particolare, solo un soggetto (0,75%) è risultato positivo a entrambi i test, uno (0,75%) solo alla CDT, mentre 28 (21,05%) solo all’EtG. Entrambi i marcatori erano in accordo nel 79% dei casi, con 104 risultati negativi e uno positivo. Esiste una grande variabilità tra CDT ed EtG nel rilevare il consumo cronico di alcool. Considerando le grandi variazioni tra i risultati ottenuti dalla determinazione della CDT nel siero e dell’EtG nei capelli, a causa della loro diversa cinetica, l'uso singolo della CDT è sconsigliato, mentre si suggerisce l’uso combinato di entrambi i parametri, aumentando fortemente l'accuratezza della diagnosi mediante la conferma reciproca e l'identificazione di risultati falsi positivi o falsi negativi dovuti a variazioni biologiche.Alcohol abuse is a common problem in society; however, the technical capabilities of evaluating individual alcohol consumption using objective biomarkers are rather limited at present because of the low sensibility and sensitivity of the markers actually used. This study aimed to evaluate chronic alcohol misuse by comparing older and newer biomarkers in subjects which underwent driving license review or renewal examination. Traditional biomarkers for heavy alcohol use include serum carbohydrate-deficient transferrin (CDT). Measurement of the nonoxidative ethanol metabolite, ethyl glucuronide (EtG) in hair has been proposed as a new marker with superior qualities. One hundred thirty-three subjects were tested for chronic alcohol abuse, by detecting EtG in hair samples and CDT in serum samples. Respectively, 1 (0.75%) and 29 (21.80%) subjects were positive to CDT and EtG. In particular, only one (0.75%) subject was positive to both tests, only one (0.75%) to CDT, while 28 (21.05%) only to EtG. Both markers were in agreement in 79% of the cases with 104 negative and 1 positive results. Large variability exists between CDT and EtG in detecting chronic alcohol consumption. Considering the large variations between CDT and EtG results in alcohol diagnosis, due to their different kinetics, the single use of CDT is not recommended, whereas the combined use of both parameters strongly increases the accuracy of the diagnosis by mutual confirmation and identification of false positive or false negative results, due to biological variations

Inflation and Reheating in Induced Gravity

Inflation is studied in the context of induced gravity (IG) $\gamma \sigma^2 R$, where $R$ is the Ricci scalar, $\sigma$ a scalar field and $\gamma$ a dimensionless constant. We study in detail cosmological perturbations in IG and examine both a Landau-Ginzburg (LG) and a Coleman-Weinberg (CW) potential toy models for small field and large field (chaotic) inflation and find that small field inflationary models in IG are constrained to $\gamma \lesssim 3 \times 10^{-3}$ by WMAP 5 yrs data. Finally we describe the regime of coherent oscillations in induced gravity by an analytic approximation, showing how the homogeneous inflaton can decay in its short-scale fluctuations when it oscillates around a non-zero value $\sigma_0$.Comment: 5 pages, 2 figure

Numerical simulation of early-age shrinkage effects on RC member deflections and cracking development

Shrinkage effects on short-term behavior of reinforced concrete elements are often neglected both in design code provisions and in numerical simulations. However, it is known that their influence on serviceability performance can be significant, especially in case of lightly-reinforced beams. As a matter of fact, the restraint provided by the reinforcement on concrete determines a reduction of the cracking load of the structural element, as well as an increase of its deflection. This paper deals with the modeling of early-age shrinkage effects in the field of smeared crack approaches. To this aim, an existing non-linear constitutive relation for cracked reinforced concrete elements is extended herein to include early-age concrete shrinkage. Careful verifications of the model are carried out by comparing numerical results with significant experimental data reported in technical literature, providing a good agreement both in terms of global and local behavior

Status of the Cylindical-GEM project for the KLOE-2 Inner Tracker

The status of the R&D on the Cylindrical-GEM (CGEM) detector foreseen as Inner Tracker for KLOE-2, the upgrade of the KLOE experiment at the DAFNE phi-factory, will be presented. The R&D includes several activities: i) the construction and complete characterization of the full-size CGEM prototype, equipped with 650 microns pitch 1-D longitudinal strips; ii) the study of the 2-D readout with XV patterned strips and operation in magnetic field (up to 1.5T), performed with small planar prototypes in a dedicated test at the H4-SPS beam facility; iii) the characterization of the single-mask GEM technology for the realization of large-area GEM foils.Comment: 4 pages, 10 figures, Presented at Vienna Conference on Instrumentation (Feb 15-20, 2010, Vienna, Austria). Submitted to the Proceeding

Uso de la lama del lago “El Nihuil”, digestión anaeróbica para obtención de biogás

Esta investigación consiste en mitigar los efectos naturales y artificiales causados en un lago de una localidad turística de la provincia de Mendoza. Una de las soluciones más efectivas para este caso es la poda de las algas del mismo. Pero ésta acarrea el inconveniente: deposición final de estos desechos. Se propuso aprovechar la degradación de estas plantas en forma anaeróbica. Se realizaron pruebas a escala, las que comprenden dos etapas. En la primera se verificó la producción de gas combustible y se realizaron análisis químicos de la materia antes y después de la degradación. En la segunda se midió el gas producido. Al final de este proceso se consigue también una disminución de la masa residual, la que a su vez puede ser aprovechada como fertilizante y/o mejorador de suelos. En la actualidad es fundamental encontrar nuevas fuentes de energías que contaminen menos, y un mayor aprovechamiento de los residuos.This project consists in mitigating the natural and artificial effects caused in a touristic village’s lake from Mendoza. One of the best solutions is pruning alga of the lake. But this one produces another inconvenient which is his final deposition. The solution propounded is: use it as a source of biogas degrading this plant. The anaerobic digestion was studied, and then there were done small experiment in two stages. In the first one was verified the combustible gas production. There was done a chemical analysis of this matter after the degradation and before it. In the second part of the experience we measured the gas produced. At the end of this process we had less waste, and this one can be used as fertilizer and to improve ground mechanical properties. It is truly important to found new sources of energy that are less polluting and a better use of waste.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

Uso de la lama del lago “El Nihuil”, digestión anaeróbica para obtención de biogás

Esta investigación consiste en mitigar los efectos naturales y artificiales causados en un lago de una localidad turística de la provincia de Mendoza. Una de las soluciones más efectivas para este caso es la poda de las algas del mismo. Pero ésta acarrea el inconveniente: deposición final de estos desechos. Se propuso aprovechar la degradación de estas plantas en forma anaeróbica. Se realizaron pruebas a escala, las que comprenden dos etapas. En la primera se verificó la producción de gas combustible y se realizaron análisis químicos de la materia antes y después de la degradación. En la segunda se midió el gas producido. Al final de este proceso se consigue también una disminución de la masa residual, la que a su vez puede ser aprovechada como fertilizante y/o mejorador de suelos. En la actualidad es fundamental encontrar nuevas fuentes de energías que contaminen menos, y un mayor aprovechamiento de los residuos.This project consists in mitigating the natural and artificial effects caused in a touristic village’s lake from Mendoza. One of the best solutions is pruning alga of the lake. But this one produces another inconvenient which is his final deposition. The solution propounded is: use it as a source of biogas degrading this plant. The anaerobic digestion was studied, and then there were done small experiment in two stages. In the first one was verified the combustible gas production. There was done a chemical analysis of this matter after the degradation and before it. In the second part of the experience we measured the gas produced. At the end of this process we had less waste, and this one can be used as fertilizer and to improve ground mechanical properties. It is truly important to found new sources of energy that are less polluting and a better use of waste.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES

A non-linear procedure for the numerical analysis of crack development in beams failing in shear

In this work, a consistent formulation for the representation of concrete behavior before and after cracking has been implemented into a non-linear model for the analysis of reinforced concrete structures, named 2D-PARC. Several researches have indeed pointed out that the adoption of an effective modeling for concrete, combined with an accurate failure criterion, is crucial for the correct prediction of the structural behavior, not only in terms of failure load, but also with reference to a realistic representation of crack initiation and development. This last aspect is particularly relevant at serviceability conditions in order to verify the fulfillment of structural requirements provided by Design Codes, which limit the maximum crack width due to appearance and durability issues. In more details, a constitutive model originally proposed by Ottosen and based on non-linear elasticity has been here incorporated into 2D-PARC in order to improve the numerical efficiency of the adopted algorithm, providing at the same time an accurate prediction of the structural response. The effectiveness of this procedure has been verified against significant experimental results available in the technical literature and relative to reinforced concrete beams without stirrups failing in shear, which represent a problem of great theoretical and practical importance in the field of structural engineering. Numerical results have been compared to experimental evidences not only in terms of global structural response (i.e. applied load vs. midspan deflection), but also in terms of crack pattern evolution and maximum crack widths

Uso de la lama del lago “El Nihuil”, digestión anaeróbica para obtención de biogás

Esta investigación consiste en mitigar los efectos naturales y artificiales causados en un lago de una localidad turística de la provincia de Mendoza. Una de las soluciones más efectivas para este caso es la poda de las algas del mismo. Pero ésta acarrea el inconveniente: deposición final de estos desechos. Se propuso aprovechar la degradación de estas plantas en forma anaeróbica. Se realizaron pruebas a escala, las que comprenden dos etapas. En la primera se verificó la producción de gas combustible y se realizaron análisis químicos de la materia antes y después de la degradación. En la segunda se midió el gas producido. Al final de este proceso se consigue también una disminución de la masa residual, la que a su vez puede ser aprovechada como fertilizante y/o mejorador de suelos. En la actualidad es fundamental encontrar nuevas fuentes de energías que contaminen menos, y un mayor aprovechamiento de los residuos.This project consists in mitigating the natural and artificial effects caused in a touristic village’s lake from Mendoza. One of the best solutions is pruning alga of the lake. But this one produces another inconvenient which is his final deposition. The solution propounded is: use it as a source of biogas degrading this plant. The anaerobic digestion was studied, and then there were done small experiment in two stages. In the first one was verified the combustible gas production. There was done a chemical analysis of this matter after the degradation and before it. In the second part of the experience we measured the gas produced. At the end of this process we had less waste, and this one can be used as fertilizer and to improve ground mechanical properties. It is truly important to found new sources of energy that are less polluting and a better use of waste.Asociación Argentina de Energías Renovables y Medio Ambiente (ASADES