Thermal Relics in Modified Cosmologies: Bounds on Evolution Histories of the Early Universe and Cosmological Boosts for PAMELA

Alternative cosmologies, based on extensions of General Relativity, predict modified thermal histories in the Early Universe during the pre Big Bang Nucleosynthesis (BBN) era, epoch which is not directly constrained by cosmological observations. When the expansion rate is enhanced with respect to the standard case, thermal relics typically decouple with larger relic abundances. The correct value of the relic abundance is therefore obtained for larger annihilation cross--sections, as compared to standard cosmology. A direct consequence is that indirect detection rates are enhanced. Extending previous analyses of ours, we derive updated astrophysical bounds on the dark matter annihilation cross sections and use them to constrain alternative cosmologies in the pre--BBN era. We also determine the characteristics of these alternative cosmologies in order to provide the correct value of relic abundance for a thermal relic for the (large) annihilation cross--section required to explain the PAMELA results on the positron fraction, therefore providing a "cosmological boost" solution to the dark matter interpretation of the PAMELA data.Comment: 19 pages, 27 figures, matches published versio

Omega-3 Polyunsaturated Fatty Acids in Blood Pressure Control and Essential Hypertension

Hypertension is a worldwide problem that affects up to 22% of adults and contributes to the global burden of disability due to cardiovascular disease. Several factors influence blood pressure and participate to the development of hypertension. Among these factors, polyunsaturated fatty acids of the omega-3 family (omega-3 PUFA) are effective hypotensive agents. Through their anti-inflammatory and antioxidant properties, omega-3 PUFA can improve cardiac hemodynamics and vascular function and potentially reduce arterial stiffness and atherosclerotic damage. However, despite this promising evidence many meta-analyses on the cardiovascular effect of omega-3 PUFA were inconclusive. The choice of the omega-3 PUFA sources, baseline tissue content of these fatty acids, and individual compliance to their intake can be reasons for such a discrepancy between studies. Basic and clinical research on these fatty acids documents interesting mechanisms through which these molecules could be useful in the treatment of hypertension and its related organ damage. The role of the maternal dietary habit during pregnancy and the quality of prenatal growth on the effect of omega-3 PUFA in cardiovascular system need further investigations. This chapter summarizes the literature of the past 30 years on the antihypertensive effects of this family of essential fatty acids

Atomic responses to general dark matter-electron interactions

In the leading paradigm of modern cosmology, about 80% of our Universe's matter content is in the form of hypothetical, as yet undetected particles. These do not emit or absorb radiation at any observable wavelengths, and therefore constitute the so-called Dark Matter (DM) component of the Universe. Detecting the particles forming the Milky Way DM component is one of the main challenges for astroparticle physics and basic science in general. One promising way to achieve this goal is to search for rare DM-electron interactions in low-background deep underground detectors. Key to the interpretation of this search is the response of detectors' materials to elementary DM-electron interactions defined in terms of electron wave functions' overlap integrals. In this work, we compute the response of atomic argon and xenon targets used in operating DM search experiments to general, so far unexplored DM-electron interactions. We find that the rate at which atoms can be ionized via DM-electron scattering can in general be expressed in terms of four independent atomic responses, three of which we identify here for the first time. We find our new atomic responses to be numerically important in a variety of cases, which we identify and investigate thoroughly using effective theory methods. We then use our atomic responses to set 90% confidence level (C.L.) exclusion limits on the strength of a wide range of DM-electron interactions from the null result of DM search experiments using argon and xenon targets.Comment: 30 pages, 10 figures. Code available at https://github.com/temken/DarkARC and https://doi.org/10.5281/zenodo.3581334 . v2: matches published versio

Enlarging mSUGRA parameter space by decreasing pre-BBN Hubble rate in Scalar-Tensor Cosmologies

We determine under what conditions Scalar Tensor cosmologies predict an expansion rate which is reduced as compared to the standard General Relativity case. We show that ST theories with a single matter sector typically predict an enchanced Hubble rate in the past, as a consequence of the requirement of an attractive fixed point towards General Relativity at late times. Instead, when additional matter sectors with different conformal factors are added, the late time convergence to General Relativity is mantained and at the same time a reduced expansion rate in the past can be driven. For suitable choices of the parameters which govern the scalar field evolution, a sizeable reduction (up to about 2 orders of magnitude) of the Hubble rate prior to Big Bang Nucleosynthesis can be obtained. We then discuss the impact of these cosmological models on the relic abundance of dark matter is minimal Supergravity models: we show that the cosmologically allowed regions in parameter space are significantly enlarged, implying a change in the potential reach of LHC on the neutralino phenomenology.Comment: 10 pages, 7 figure

Dark Matter Relic Abundance and Scalar-Tensor Dark Energy

Scalar-tensor theories of gravity provide a consistent framework to accommodate an ultra-light quintessence scalar field. While the equivalence principle is respected by construction, deviations from General Relativity and standard cosmology may show up at nucleosynthesis, CMB, and solar system tests of gravity. After imposing all the bounds coming from these observations, we consider the expansion rate of the universe at WIMP decoupling, showing that it can lead to an enhancement of the dark matter relic density up to few orders of magnitude with respect to the standard case. This effect can have an impact on supersymmetric candidates for dark matter.Comment: 12 pages, 13 figures; V2: references added, matches published versio

a continuous model for the railway track analysis in the lateral plane

Abstract This paper deals with a mechanical model for the analysis of the railway track behaviour built by exploiting the periodicity of the track-structure. The starting point of this study is the analysis of the inner forces transferring modes. They have been determined by the unit principal vectors analysis of the base cell transfer matrix. The proposed model is able to reproduce accurately the track behaviour in transferring its inner forces. However, solutions that are equilibrated but not kinematically admissible are obtained from it when transversal loads are applied. In additions, only boundary conditions compatibles with the track transferring modes can be satisfied. This inconsistency is eliminated by superposition of a corrective deformed shape. This is derived from the eigenvectors of the transfer matrix pertaining to self-equilibrated systems of bending moments decaying along the track. The application field of the proposed track model is also discussed and the results of a validation study carried out by F.E. analysis are finally presented

Polyphenols rich diets and risk of type 2 diabetes

Type 2 diabetes is an increasing health concern worldwide. Both genetic and environmental risk factors as improper dietary habits or physical inactivity are known to be crucial in the pathogen-esis of type 2 diabetes. Polyphenols are a group of plant-derived compounds with anti-inflammatory and antioxidant properties that are associated with a low prevalence of metabolic conditions charac-terized by insulin resistance, including obesity, diabetes, and hypertension. Moreover, there is now full awareness that foods that are rich in phytochemicals and polyphenols could play an important role in preserving human cardiovascular health and substantial clinical evidence indicates that regu-lar dietary consumption of such foods affects favorably carbohydrate metabolism. This review briefly summarizes the evidence relating dietary patterns rich in polyphenols with glucose metabolism and highlights the potential benefits of these compounds in the prevention of type 2 diabetes

Italian viticulture: A multi-faceted model of development and regression.

Wine can be considered a niche product on the drinks market, due to the annual turnover it generates and the dispersion of the productive matrix which controls its production. However, it takes on a symbolic value compared to other drinks and boasts a unique link with the territory. Typicity translated into territorial values has brought about the success of winemaking regions of great national and international fame. However, it is necessary to communicate the values and adopt the consequent measures for other areas in a secondary position or with an intermediate development. The value of wine ex-cellar, unbottled and before vat has been analyzed taking into account production in different market segments, a basic element for estimating the value of the GSP per hectare of vineyard. This paper is based on the study of physical, economic and motivational parameters that determine the primary value, the cause for consolidating or abandoning winegrowing. Decisions made by the vinegrower translate into nursery demand which, in turn, determines the varieties and surface areas of the future vineyard