Search results for "FOS"
showing 10 items of 15075 documents
Effective charge from lattice QCD
2020
Using lattice configurations for quantum chromodynamics (QCD) generated with three domain-wall fermions at a physical pion mass, we obtain a parameter-free prediction of QCD's renormalisation-group-invariant process-independent effective charge, $\hat\alpha(k^2)$. Owing to the dynamical breaking of scale invariance, evident in the emergence of a gluon mass-scale, this coupling saturates at infrared momenta: $\hat\alpha(0)/\pi=0.97(4)$. Amongst other things: $\hat\alpha(k^2)$ is almost identical to the process-dependent (PD) effective charge defined via the Bjorken sum rule; and also that PD charge which, employed in the one-loop evolution equations, delivers agreement between pion parton di…
Effective Hamiltonians in Nonrelativistic Quantum Electrodynamics
2021
In this paper, we consider some second-order effective Hamiltonians describing the interaction of the quantum electromagnetic field with atoms or molecules in the nonrelativistic limit. Our procedure is valid only for off-energy-shell processes, specifically virtual processes such as those relevant for ground-state energy shifts and dispersion van der Waals and Casimir-Polder interactions, while on-energy-shell processes are excluded. These effective Hamiltonians allow for a considerable simplification of the calculation of radiative energy shifts, dispersion, and Casimir-Polder interactions, including in the presence of boundary conditions. They can also provide clear physical insights int…
Is there light after depth? Distribution of periphyton chlorophyll and productivity in lake littoral zones
2014
Periphyton and phytoplankton contribute to the base of lake food webs, and both groups of microalgae are influenced by resources and physical forcing. Spatial variation in light availability interacts with the physical dynamics of the water column to create predictable depth gradients in resources and disturbance that may differentially affect periphyton vs phytoplankton. We characterized the depth distribution of chlorophyll and productivity of periphyton on sediments (epipelon) and phytoplankton in the euphotic zones of 13 oligomesotrophic lakes that span a large size gradient (0.017–32,600 km2 ). Epipelic chlorophyll usually increased with depth in the epilimnion. Light was the primary d…
New tellurium-containing ring systems
2007
The recent discovery of a suitable synthesis of the monoanionic ditelluroimidodiphosphinate ligands [TePR2NPR2Te]− (R = Ph, iPr, tBu) has facilitated investigations of the fundamental chemistry of these chelating inorganic ligands. This article is focused on aspects of that chemistry in which the behaviour of this ditelluro PNP ligand differs from that of the well-studied dithio and diseleno congeners. The emphasis is on new tellurium-containing ring systems formed in: (a) redox transformations and (b) the synthesis of metal complexes. peerReviewed
Epistemologia metodologica e prassi operativa. Benefici e applicazioni nei contesti comunitari residenziali
2019
Alcune ricerche sostengono che l’animale, nella sua diversità sia morfologica che comportamentale, solleciti nel bambino la formazione e lo sviluppo dell’immaginario, attraverso l’offerta di più modelli per i suoi processi elaborativi e il rafforzamento della sua fantasia ( Piccino, 2014). L’animale svolge un ruolo formativo importante nello sviluppo mentale dei bambini, inoltre interagire con la diversità di cui l’animale è costituito o il semplice riferirsi alla diversità dell’animale, aiuterebbe il bambino a trasformare la differenza in curiosità e tolleranza. Attraverso specifiche attività che implicano una relazione positiva, gli interventi assistiti con gli animali possono veicolare l…
The Dolia Defossa and viticulture at Vagnari
2022
At Vagnari, the fabric of the dolia defossa was distinctively different from that present in all the other ceramics from the site, as it was a distinctive orangey-red with black, glassy particles and reddish-brown grit fragments. The surviving lid fragment, on the other hand, is made of a fairly fine buff clay, suggesting it was made somewhere else. It is not unusual that dolia and lids might be made of different clays and in different workshops, as they are in Gallia Narbonensis, where some analysed lids were made in Rome, but the vessels were local. The recognition that it is important to conduct fabric analyses on dolia retrieved in archaeological excavations, whether on land or in the s…
Efecto de la duloxetina sobre la expresión de fos en el tronco del encéfalo y en la médula espinal de la rata en modelos de dolor persistente
2015
A pesar de los ensayos clínicos en humanos que avalan el uso clínico de la duloxetina en dolor neuropático, todavía no se conoce en profundidad el sustrato anatómico en el que subyace el efecto analgésico de este antidepresivo. Nuestra revisión bibliográfica sobre el tema no ha ofrecido ni un solo trabajo en el que se pretenda identificar las estructuras neurales supraespinales que se activan o al menos se ven alteradas tras la administración de duloxetina en animales sanos, o con diferentes tipos de dolor neuropático. Parece, sin embargo, que la identificación de los centros troncoencefálicos que ven alterada su actividad neuronal por la administración de estas sustancias, sería de gran ut…
Measuring nuclear reaction cross sections to extract information on neutrinoless double beta decay
2017
Neutrinoless double beta decay (0v\b{eta}\b{eta}) is considered the best potential resource to access the absolute neutrino mass scale. Moreover, if observed, it will signal that neutrinos are their own anti-particles (Majorana particles). Presently, this physics case is one of the most important research "beyond Standard Model" and might guide the way towards a Grand Unified Theory of fundamental interactions. Since the 0v\b{eta}\b{eta} decay process involves nuclei, its analysis necessarily implies nuclear structure issues. In the NURE project, supported by a Starting Grant of the European Research Council (ERC), nuclear reactions of double charge-exchange (DCE) are used as a tool to extr…
RECUPERO A FINI AGRONOMICI DI SUOLI PALUDOSO-SALMASTRI DELLA MARISMA DI LEBRIJA (SPAGNA)
2007
La salinizzazione del suolo interessa un’area di circa 830 milioni di ettari. Le principali conseguenze nelle aree coltivate sono una graduale perdita di fertilità dei suoli, con conseguente diminuzione o perdita dei raccolti. In Spagna, dove oltre 100 mila ettari di terre irrigate è affetto da salinità e un altro 15% è a rischio, la bonifica a scopo agricolo è una pratica comune. Obiettivo della presente ricerca è stato quello di investigare le variazioni della biomassa e dell’attività microbica in suoli paludoso-salmastri bonificati e non. L’area di studio è la Marisma di Lebrija, nell’estuario del fiume Guadalquivir, nel sud-ovest della Spagna. Sono stati presi in esame due parcelle di t…
Dynamics and extraction of quantum discord in a multipartite open system
2011
We consider a multipartite system consisting of two noninteracting qubits each embedded in a single-mode leaky cavity, in turn connected to an external bosonic reservoir. Initially, we take the two qubits in an entangled state while the cavities and the reservoirs have zero photons. We investigate, in this six-partite quantum system, the transfer of quantum discord from the qubits to the cavities and reservoirs. We show that this transfer occurs also when the cavities are not entangled. Moreover, we discuss how quantum discord can be extracted from the cavities and transferred to distant systems by traveling leaking photons, using the input-output theory.