Complesso Universitario Monte gelo

Napoli, Italy

Complesso Universitario Monte gelo

Napoli, Italy
Time filter
Source Type

Castorina E.,International School for Advanced Studies | Franca U.,University of Valencia | Lattanzi M.,University of Milan Bicocca | Lesgourgues J.,CERN | And 5 more authors.
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2012

While the baryon asymmetry of the Universe is nowadays well measured by cosmological observations, the bounds on the lepton asymmetry in the form of neutrinos are still significantly weaker. We place limits on the relic neutrino asymmetries using some of the latest cosmological data, taking into account the effect of flavor oscillations. We present our results for two different values of the neutrino mixing angle θ 13, and show that for large θ 13 the limits on the total neutrino asymmetry become more stringent, diluting even large initial flavor asymmetries. In particular, we find that the present bounds are still dominated by the limits coming from big bang nucleosynthesis, while the limits on the total neutrino mass from cosmological data are essentially independent of θ 13. Finally, we perform a forecast for Cosmic Origins Explorer, taken as an example of a future cosmic microwave background experiment, and find that it could improve the limits on the total lepton asymmetry approximately by up to a factor 6.6. © 2012 American Physical Society.

Bouhmadi-Lopez M.,University of Lisbon | Capozziello S.,University of Naples Federico II | Capozziello S.,Complesso Universitario Monte gelo | Cardone V.F.,University of Naples Federico II | Cardone V.F.,University of Molise
Physical Review D - Particles, Fields, Gravitation and Cosmology | Year: 2010

Cosmography is a useful tool to constrain cosmological models, in particular, dark energy models. In the case of modified theories of gravity, where the equations of motion are generally quite complicated, cosmography can contribute to select realistic models without imposing arbitrary choices apriori. Indeed, its reliability is based on the assumptions that the universe is homogeneous and isotropic on large scale and luminosity distance can be "tracked" by the derivative series of the scale factor a(t). We apply this approach to induced gravity brane-world models where an f(R) term is present in the brane effective action. The virtue of the model is to self-accelerate the normal and healthy Dvali-Gabadadze-Porrati branch once the f(R) term deviates from the Hilbert-Einstein action. We show that the model, coming from a fundamental theory, is consistent with the ΛCDM scenario at low redshift. We finally estimate the cosmographic parameters fitting the Union2 TypeIa Supernovae data set and the distance priors from baryon acoustic oscillations and then provide constraints on the present day values of f(R) and its second and third derivatives. © 2010 The American Physical Society.

Cimmino A.,Complesso Universitario Monte gelo | Andolfi A.,Complesso Universitario Monte gelo | Abouzeid M.,Ain Shams University | Evidente A.,Complesso Universitario Monte gelo
Phytochemistry Reviews | Year: 2013

This review deals with the sources and chemical and biological characterization of phytotoxic polyphenols produced essentially by pathogenic fungi of forest and crop plants and of weeds. Their potential use as natural herbicides and fungicides is discussed. The use of some polyphenols which could be applied as an alternative method to control parasitic weeds, the so called "suicidal germination", will be covered. The sources and the isolation and identification of polyphenols produced by some crop plants in consequence of the attack of pathogenic fungi as plant defence compounds (phytoalexins), are also described. © Springer Science+Business Media 2013.

Mangano G.,Complesso Universitario Monte gelo | Lizzi F.,Complesso Universitario Monte gelo | Lizzi F.,University of Naples Federico II | Lizzi F.,University of Barcelona | Porzio A.,CNR Institute of Neuroscience
International Journal of Modern Physics A | Year: 2015

Motivated by the Dirac idea that fundamental constants are dynamical variables and by conjectures on quantum structure of space-time at small distances, we consider the possibility that Planck constant h is a time depending quantity, undergoing random Gaussian fluctuations around its measured constant mean value, with variance σ2 and a typical correlation timescale Δt. We consider the case of propagation of a free particle and a one-dimensional harmonic oscillator coherent state, and show that the time evolution in both cases is different from the standard behavior. Finally, we discuss how interferometric experiments or exploiting coherent electromagnetic fields in a cavity may put effective bounds on the value of τ = σ2Δt. © 2015 World Scientific Publishing Company.

Capozziello S.,University of Naples Federico II | Capozziello S.,Complesso Universitario Monte gelo | Saez-Gomez D.,Institute Of Ciencies Of Lespai Ice Csic Ieec
Annalen der Physik | Year: 2012

Birkhoff's theorem is discussed in the frame of f(R) gravity by using its scalar-tensor representation. Modified gravity has become very popular in recent times as it is able to reproduce the unification of inflation and late-time acceleration with no need of a dark energy component or an inflation field. Here, another aspect of modified f(R) gravity is studied, specifically the range of validity of Birkhoff's theorem, compared with another alternative to general relativity, the well-known Brans-Dicke theory. As a novelty, here both theories are studied using a conformal transformation and writing the actions in the Einstein frame, where spherically symmetric solutions are studied using perturbation techniques. The differences between both theories are analyzed as well as the validity of the theorem within the Jordan and Einstein frames, where interesting results are obtained. © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Capolupo L.,University of Naples Federico II | Faraco V.,University of Naples Federico II | Faraco V.,Complesso Universitario Monte gelo
Applied Microbiology and Biotechnology | Year: 2016

Lignocellulosic biomass is the most abundant, low-cost, bio-renewable resource that holds enormous importance as alternative source for production of biofuels and other biochemicals that can be utilized as building blocks for production of new materials. Enzymatic hydrolysis is an essential step involved in the bioconversion of lignocellulose to produce fermentable monosaccharides. However, to allow the enzymatic hydrolysis, a pretreatment step is needed in order to remove the lignin barrier and break down the crystalline structure of cellulose. The present manuscript is dedicated to reviewing the most commonly applied “green” pretreatment processes used in bioconversion of lignocellulosic biomasses within the “biorefinery” concept. In this frame, the effects of different pretreatment methods on lignocellulosic biomass are described along with an in-depth discussion on the benefits and drawbacks of each method, including generation of potentially inhibitory compounds for enzymatic hydrolysis, effect on cellulose digestibility, and generation of compounds toxic for the environment, and energy and economic demand. © 2016, The Author(s).

Bloino J.,Normal School of Pisa | Bloino J.,Complesso Universitario Monte gelo | Biczysko M.,Complesso Universitario Monte gelo | Santoro F.,CNR Institute for Chemical and Physical Processes | Barone V.,Normal School of Pisa
Journal of Chemical Theory and Computation | Year: 2010

An effective time-independent approach to compute vibrationally resolved optical spectra from first principles is generalized toward the computation of one-photon electronic spectra induced by either electric or magnetic transition dipoles or by their mutual interaction. These encompass absorption, emission, and circular dichroism spectra. Additionally, the proposed computational scheme is extended to cover a broad range of approximations to evaluate vibronic transitions within both vertical and adiabatic frameworks and to be able to take into account the effects of the temperature. The presented computational tool is integrated into a general purpose computational chemistry package and offers a simple and an easy-to-use way to evaluate one-photon electronic spectra, starting from electronic structure calculations chosen according to the system under study, from fully quantum mechanical descriptions to discrete/continuum quantum mechanical/MM/polarizable continuum models. © 2010 American Chemical Society.

Alessandra P.,Complesso Universitario Monte gelo | Cinzia P.,Complesso Universitario Monte gelo | Paola G.,Complesso Universitario Monte gelo | Vincenza F.,Complesso Universitario Monte gelo | Sannia G.,Complesso Universitario Monte gelo
Bioengineered Bugs | Year: 2010

Laccases are blue multicopper oxidases, catalyzing the oxidation of an array of aromatic substrates concomitantly with the reduction of molecular oxygen to water. These enzymes are implicated in a variety of biological activities. Most of the laccases studied thus far are of fungal origin. The large range of substrates oxidized by laccases has raised interest in using them within different industrial fields, such as pulp delignification, textile dye bleaching and bioremediation. Laccases secreted from native sources are usually not suitable for large-scale purposes, mainly due to low production yields and high cost of preparation/ purification procedures. Heterologous expression may provide higher enzyme yields and may permit to produce laccases with desired properties (such as different substrate specificities, or improved stabilities) for industrial applications. This review surveys researches on heterologous laccase expression focusing on the pivotal role played by recombinant systems towards the development of robust tools for greening modern industry. © 2010 Landes Bioscience.

Giardina P.,Complesso Universitario Monte gelo | Faraco V.,Complesso Universitario Monte gelo | Pezzella C.,Complesso Universitario Monte gelo | Piscitelli A.,Complesso Universitario Monte gelo | And 2 more authors.
Cellular and Molecular Life Sciences | Year: 2010

Laccases (benzenediol:oxygen oxidoreductases, EC are blue multicopper oxidases that catalyze the oxidation of an array of aromatic substrates concomitantly with the reduction of molecular oxygen to water. In fungi, laccases carry out a variety of physiological roles during their life cycle. These enzymes are being increasingly evaluated for a variety of biotechnological applications due to their broad substrate range. In this review, the most recent studies on laccase structural features and catalytic mechanisms along with analyses of their expression are reported and examined with the aim of contributing to the discussion on their structure-function relationships. Attention has also been paid to the properties of enzymes endowed with unique characteristics and to fungal laccase multigene families and their organization.

Pezzella C.,Complesso Universitario Monte gelo | Guarino L.,Complesso Universitario Monte gelo | Piscitelli A.,Complesso Universitario Monte gelo
Cellular and Molecular Life Sciences | Year: 2015

An analysis of the scientific literature published in the last 10 years reveals a constant growth of laccase applicative research in several industrial fields followed by the publication of a great number of patents. The Green Chemistry journal devoted the cover of its September 2014 issue to a laccase as greener alternative for chemical oxidation. This indicates that laccase ''never-ending story'' has found a new promising trend within the constant search for efficient (bio)catalysts able tomeet the 12 green chemistry principles.A survey of ancient and cutting-edge uses of laccase in different industrial sectors is offered in this review with the aim both to underline their potential and to provide inspiration for new ones. Applications in textile and food fields have been deeply described, as well as examples concerning polymer synthesis and laccase-catalysed grafting. Recent applications in pharmaceutical and cosmetic industry have also been reviewed. © Springer Basel 2015.

Loading Complesso Universitario Monte gelo collaborators
Loading Complesso Universitario Monte gelo collaborators