5,154 research outputs found
Symmetries and Ambiguities in the linear sigma model with light quarks
We investigate the role of undetermined finite contributions generated by
radiative corrections in a linear sigma model with quarks.
Although some of such terms can be absorbed in the renormalization procedure,
one such contribution is left in the expression for the pion decay constant.
This arbitrariness is eliminated by chiral symmetry.Comment: 9 pages. Added references through the text; an author was added due
to an important contribution; corrected typos; the title also was changed.
Submitted to Modern Physics Letter
Contribution to an efficient transmission of information to the textile fashion consumer and the influence in sustainable attitudes
The concepts involved in sustainable textile fashion, demanding good knowledge about raw materials, processes, end use properties and circuits amongst others, are able to determine the way the textile product is designed and the behavior of the consumer, regarding life style and buying decisions. The textile product`s life integrates raw materials, their processing, distribution, use by the consumer and destination of the product after useful lifetime, this is, his complete life cycle. It is very important to recognize the power of the consumer to influence parameters related to sustainability, namely when he decides how, when and why he buys and afterwards by the attitudes taken during and after use.
The conscious act of consumption involves ethical, ecological and technical knowledge in which the concern is overall lifecycle of the fashion product and not exclusively aesthetic and symbolic values strongly related with its ephemeral nature.
The present work proposes the classification of textile products by means of an innovative label aiming to establish a rating related to the Life of Fashion Products, by using parameters considered with especial impact in lifecycle, as textile fibers, processing conditions, generated wastes, commercialization circuits, durability and cleaning procedures. This label for sustainable fashion products aims to assist the stakeholders with informed attitudes and correct decisions in order to promote the objectives of sustainable fashion near designers, consumers and industrial experts.This work is financed by FEDER funds through the Competitivity Factors Operational Programme -
COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of
the projec
EVIDENCIAÇÃO DE INFORMAÇÕES AMBIENTAIS: PROPOSTA DE UM INDICADOR A PARTIR DA PERCEPÇÃO DE ESPECIALISTAS
This paper is aimed at listing environmental attributes, according to the degree of importance of disclosure, to compose a truly Brazilian indicator that assesses the quality of environmental information disclosure. “Environmental accounting/sustainability” experts and environmental disclosure attributes were selected, based on Brazilian and international studies. Through Delphi rounds, the experts outlined the list of the most relevant attributes to compose the indicator. The Environmental Disclosure Indicator – EDI consists of ten attributes than combine practicality and representativeness of the quality of environmental information disclosure. The results revealed a high degree of importance and, therefore, a greater weight of qualitative attributes, such as “Environmental Impacts of Products and Processes” and “Information about Residues”. The study contributes by revealing “what” should be disclosed prioritarily, that is, which are the essential environmental attributes. It contributes to verify whether the amount of environmental information companies have disclosed have necessarily meant disclosure quality. As it provides an instrument to quantify the quality of environmental disclosure, the study permits further research about the association between this disclosure and other company aspects, such as performance and corporate governance.O artigo tem por objetivo elencar atributos ambientais, conforme o grau de importância de disclosure, para composição de um indicador genuinamente brasileiro que avalie qualidade de evidenciação de informações ambientais. Selecionaram-se especialistas da área “contabilidade ambiental/sustentabilidade” e atributos de evidenciação ambiental subsidiados por estudos nacionais e internacionais. Por meio de rodadas Delphi, os especialistas delinearam o rol de atributos mais relevantes para a composição do indicador. O Indicador de Disclosure Ambiental – IDA é composto por dez atributos que combinam praticidade e representatividade da qualidade de evidenciação de informações ambientais. Os resultados revelaram alto grau de importância e, portanto, maior peso para atributos qualitativos, como “Impactos Ambientais de Produtos e Processos” e “Informações sobre Resíduos”. A contribuição do estudo consiste em revelar “o que” se deve evidenciar prioritariamente, ou seja, quais são os atributos ambientais essenciais. Contribui para que verifique se a quantidade de informações ambientais evidenciadas pelas companhias tem significado necessariamente qualidade de disclosure. Por fornecer um instrumento para quantificação da qualidade do disclosure ambiental, o estudo possibilita pesquisas posteriores sobre a associação entre esta evidenciação e demais aspectos das companhias, como desempenho e governança corporativ
Evidence of Two Distinct Dynamic Critical Exponents in Connection with Vortex Physics
The dynamic critical exponent is determined from numerical simulations
for the three-dimensional (3D) lattice Coulomb gas (LCG) and the 3D XY models
with relaxational dynamics. It is suggested that the dynamics is characterized
by two distinct dynamic critical indices and related to the
divergence of the relaxation time by and
, where is the correlation length and the
wavevector. The values determined are and for the
3D LCG and and for the 3D XY model. It is argued
that the nonlinear exponent relates to , whereas the usual
Hohenberg-Halperin classification relates to . Possible implications for the
interpretation of experiments are pointed out. Comparisons with other existing
results are discussed.Comment: to appear in PR
Failure mechanisms and surface roughness statistics of fractured Fontainebleau sandstone
In an effort to investigate the link between failure mechanisms and the
geometry of fractures of compacted grains materials, a detailed statistical
analysis of the surfaces of fractured Fontainebleau sandstones has been
achieved. The roughness of samples of different widths W is shown to be self
affine with an exponent zeta=0.46 +- 0.05 over a range of length scales ranging
from the grain size d up to an upper cut-off length \xi = 0.15 W. This low zeta
value is in agreement with measurements on other sandstones and on sintered
materials. The probability distributions P(delta z,delta h) of the variations
of height over different distances delta z > d can be collapsed onto a single
Gaussian distribution with a suitable normalisation and do not display
multifractal features. The roughness amplitude, as characterized by the
height-height correlation over fixed distances delta z, does not depend on the
sample width, implying that no anomalous scaling of the type reported for other
materials is present. It is suggested, in agreement with recent theoretical
work, to explain these results by the occurence of brittle fracture (instead of
damage failure in materials displaying a higher value of zeta = 0.8).Comment: 7 page
Evaluation of canonical siRNA and Dicer substrate RNA for inhibition of hepatitis C virus genome replication - a comparative study
Hepatitis C virus (HCV) frequently establishes persistent infections in the liver, leading to the development of chronic hepatitis and, potentially, to liver cirrhosis and hepatocellular carcinoma at later stages. The objective of this study was to test the ability of five Dicer substrate siRNAs (DsiRNA) to inhibit HCV replication and to compare these molecules to canonical 21 nt siRNA. DsiRNA molecules were designed to target five distinct regions of the HCV genome - the 5′ UTR and the coding regions for NS3, NS4B, NS5A or NS5B. These molecules were transfected into Huh7.5 cells that stably harboured an HCV subgenomic replicon expressing a firefly luciferase/neoR reporter (SGR-Feo-JFH-1) and were also tested on HCVcc-infected cells. All of the DsiRNAs inhibited HCV replication in both the subgenomic system and HCVcc-infected cells. When DsiRNAs were transfected prior to infection with HCVcc, the inhibition levels reached 99.5%. When directly compared, canonical siRNA and DsiRNA exhibited similar potency of virus inhibition. Furthermore, both types of molecules exhibited similar dynamics of inhibition and frequencies of resistant mutants after 21 days of treatment. Thus, DsiRNA molecules are as potent as 21 nt siRNAs for the inhibition of HCV replication and may provide future approaches for HCV therapy if the emergence of resistant mutants can be addressed
Hospedabilidade de espécies frutíferas a meloidogyne ethiopica.
bitstream/item/67317/1/Boletim-144-corrigido.pd
Peritrophic membrane genes from Diabrotica virgifera virgifera and their potential application as target in pest management in future.
Continuous Time Monte Carlo and Spatial Ordering in Driven Lattice Gases: Application to Driven Vortices in Periodic Superconducting Networks
We consider the two dimensional (2D) classical lattice Coulomb gas as a model
for magnetic field induced vortices in 2D superconducting networks. Two
different dynamical rules are introduced to investigate driven diffusive steady
states far from equilibrium as a function of temperature and driving force. The
resulting steady states differ dramatically depending on which dynamical rule
is used. We show that the commonly used driven diffusive Metropolis Monte Carlo
dynamics contains unphysical intrinsic randomness that destroys the spatial
ordering present in equilibrium (the vortex lattice) over most of the driven
phase diagram. A continuous time Monte Carlo (CTMC) is then developed, which
results in spatially ordered driven states at low temperature in finite sized
systems. We show that CTMC is the natural discretization of continuum Langevin
dynamics, and argue that it gives the correct physical behavior when the
discrete grid represents the minima of a periodic potential. We use detailed
finite size scaling methods to analyze the spatial structure of the steady
states. We find that finite size effects can be subtle and that very long
simulation times can be needed to arrive at the correct steady state. For
particles moving on a triangular grid, we find that the ordered moving state is
a transversely pinned smectic that becomes unstable to an anisotropic liquid on
sufficiently large length scales. For particles moving on a square grid, the
moving state is a similar smectic at large drives, but we find evidence for a
possible moving solid at lower drives. We find that the driven liquid on the
square grid has long range hexatic order, and we explain this as a specifically
non-equilibrium effect. We show that, in the liquid, fluctuations are diffusive
in both the transverse and longitudinal directions.Comment: 29 pages, 35 figure
Host status of fruit plants to meloidogyne enterolobii.
Edição dos Proceedings do 6th International Congress of Nematology, Cape Town, South Africa, May 2014
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