1,224 research outputs found
Medium-induced radiation with vacuum propagation in the pre-hydrodynamics phase
The recent discovery of the potential of jet quenching observables to
constrain the initial stages after a heavy-ion collision makes imperative to
have a better understanding of the process of medium-induced radiation before
the formation of the quark-gluon plasma (QGP) and its impact on observables at
high-. In this work, we generalize the BDMPS-Z framework for
medium-induced radiation to account for additional emissions occurring before
the creation of the QGP. For simplicity, we assume that during the
pre-hydrodynamics phase the hard parton propagates as in vacuum. This set-up,
allows us to isolate the contribution from the additional initial radiation by
comparing with the usual scenarios in which the emitter is created inside the
medium but with different starting points. Using both a numerical
implementation of the fully resummed emission spectrum and the usual analytical
approximations, we find that replacing an initial slab of the medium by vacuum
yields to a significant reduction of the emission spectrum for low radiated
gluon energies, while the high-energy tails remain largely unmodified. Finally,
we assess the effect of replacing the initial medium by vacuum propagation on
the single-inclusive particle suppression and high- azimuthal
asymmetry . Our findings indicate that considering vacuum propagation
prior to hydrodynamization leads to an increase in the , thus
corroborating the importance of the treatment of jet quenching in the initial
stages for the correct description of both observables.Comment: 25 pages, 9 figures. Matches published version in JHE
Social Organizational Life Cycle Assessment (SO-LCA) and Organization 4.0: An easy-to-implement method
Organizations often face difficulties when measuring their social performance. The lack of international standards, the qualitative/quantitative nature of data, and the unavailability of primary sources all hinder social impact assessments, especially in manufacturing settings. To fill these gaps, the method proposes a simple application protocol of Social Organizational Life Cycle Assessment (SO-LCA), customized for an Italian ceramic tile manufacturer. The method leverages Industry 4.0 digital technologies to collect real-time primary and site-specific social data, making the social assessment dynamic. The managerial approach adopted for the selection of social metrics and weighting of indicators and indexes, can support the transition of the manufacturing organization into Organization 4.0. The method also provides a contribution to the operational validation of the UNEP guidelines by extending their area of application. Finally, the proposed method gives substance to social responsibility through social accounting, helping the organization to measure the correct social impact starting from the detailed data, namely the decisions made in the business and in production. • Social Organizational Life Cycle Assessment (SO-LCA) application protocol validated in Industry 4.0 environment. • Social metrics directly linked to production and business processes for the dynamic assessment of social performance. • Easy replicability of the method in other organizational contexts
4D spin-2 fields from 5D Chern-Simons theory
We consider a 5-dimensional Chern-Simons gauge theory for the isometry group of Anti-de-Sitter spacetime, AdS(4+1) similar or equal to SO(4, 2), and invoke different dimensional reduction schemes in order to relate it to 4-dimensional spin-2 theories. The AdS gauge algebra is isomorphic to a parametrized 4-dimensional conformal algebra, and the gauge fields corresponding to the generators of non-Abelian translations and special conformal transformations reduce to two vierbein fields in D = 4. Besides these two vierbeine, our reduction schemes leave only the Lorentz spin connection as an additional dynamical field in the 4-dimensional theories. We identify the corresponding actions as particular generalizations of Einstein-Cartan theory, conformal gravity and ghost-free bimetric gravity in first-order form
Local Constraints on the Oscillating G Model
We analyze the observational constraints on the effective Brans-Dicke
parameter and on the temporal variation of the effective gravitational constant
within the context of the oscillating G model, a cosmological model based on a
massive scalar field non-minimally coupled to gravity. We show that these local
constraints cannot be satisfied simultaneously once the values of the free
parameters entering the model become fixed by the global attributes of our
Universe. In particular, we show that the lower observational bound for the
effective Brans-Dicke parameter and the upper bound of the variation of the
effective gravitational constant lead to a specific value of the oscillation
amplitude which lies well below the value required to explain the periodicity
of 128 Mpc h^{-1} in the galaxy distribution observed in the pencil beam
surveys.Comment: PRD, subm., 12 pages, 1 figur
A new way of valorizing biomaterials: the use of sunflower protein for 1 a-tocopherol microencapsulation
Biopolymer based microparticles were efficiently prepared from sunflower protein (SP) wall material and a-tocopherol (T) active core using a spray-drying technique. Protein enzymatic hydrolysis and/or N-acylation were carried out to make some structural modifications to the vegetable protein. Native and hydrolyzed SP were characterized by Asymmetrical Flow Field-Flow Fractionation (AsFlFFF). Results of AsFlFFF confirmed that size of proteinic macromolecules was influenced by degree of hydrolysis. The effect of protein modifications and the influence of wall/core ratio on both emulsions and microparticle properties were evaluated. Concerning emulsion properties, enzymatic hydrolysis involved a decrease in viscosity, whereas acylation did not significantly affect emulsion droplet size and viscosity. Microparticles obtained with hydrolyzed SP wall material showed lower retention efficiency (RE) than native SP microparticles (62-80% and 93% respectively). Conversely, acylation of both hydrolyzed SP and native SP allowed a higher RE to be reached (up to 100%). Increasing T concentration increased emulsion viscosity, emulsion droplet size, microparticle size, and enhanced RE. These results demonstrated the feasibility of high loaded (up to 79.2% T) microparticles
Bottom-up control of common octopus Octopus vulgaris in the Galician upwelling system, northeast Atlantic Ocean
This paper investigates the possible underlying causes of the wide interannual fluctuations
in catch of the common octopus Octopus vulgaris Cuvier, 1797 in one of the main small-scale
fisheries off the coast of Galicia (northwest Spain). Galicia is at the northern boundary of the
Iberian–Canary current upwelling system in the northeast Atlantic Ocean, where local winds induce
seasonal upwelling, largely driving the annual cycles of primary and secondary production. We
hypothesize that such dynamics are also fundamental for the survival of the planktonic stages of
octopus and set the year class strength. We address this hypothesis by investigating the influence of
upwelling on time-series of octopus fishery data. Wind stress structure during the spring–summer
(prior to the hatching peak) and autumn–winter (during the planktonic stage) was found to affect the
early life phase of this species, and explains up to 85% of the total variance of the year-to-year
variability of the adult catch. Despite this bottom-up modulation via environmental conditions, our
results also provide evidence for a between-cohort density-dependent interaction, probably caused
by cannibalism and competition for habitat.Postprin
Protocolo y mapa de diversidad funcional.
En este documento se exploran los patrones espaciales de la diversidad taxonómica y funcional de aves en ecosistemas alto andinos y humedales de Colombia y se discuten las consecuencias teóricas, de manejo y conservación del acoplamiento/desacoplamiento de ambas dimensiones de la biodiversidad. Este producto es elaborado por el Programa de Ciencias de la Diversidad en el marco del convenio 005 (13-014) entre el Instituto Humboldt y el Fondo Adaptación.BogotáSubdirección de Servicios Científicos y Proyectos Especiale
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