Maximum Entropy Inferences on the Axion Mass in Models with Axion-Neutrino Interaction

In this work we use the Maximum Entropy Principle (MEP) to infer the mass of an axion which interacts to photons and neutrinos in an effective low energy theory. The Shannon entropy function to be maximized is suitably defined in terms of the axion branching ratios. We show that MEP strongly constrains the axion mass taking into account the current experimental bounds on the neutrinos masses. Assuming that the axion is massive enough to decay into all the three neutrinos and that MEP fixes all the free parameters of the model, the inferred axion mass is in the interval $0.1\$eV$\ <m_{A}<0.2$ eV, which can be tested by forthcoming experiments such as IAXO. However, even in the case where MEP fixes just the axion mass and no other parameter, we found that $0.1$ eV $< m_A < 6.3$ eV in the DFSZ model with right-handed neutrinos. Moreover, a light axion, allowed to decay to photons and the lightest neutrino only, is determined by MEP as a viable dark matter candidate.Comment: 13 pages, 5 figures, typos corrected, figures update

Inferences on the Higgs Boson and Axion Masses through a Maximum Entropy Principle

The Maximum Entropy Principle (MEP) is a method that can be used to infer the value of an unknown quantity in a set of probability functions. In this work we review two applications of MEP: one giving a precise inference of the Higgs boson mass value; and the other one allowing to infer the mass of the axion. In particular, for the axion we assume that it has a decay channel into pairs of neutrinos, in addition to the decay into two photons. The Shannon entropy associated to an initial ensemble of axions decaying into photons and neutrinos is then built for maximization.Comment: Contributed to the 13th Patras Workshop on Axions, WIMPs and WISPs, Thessaloniki, May 15 to 19, 201

Slow down of a globally neutral relativistic e−e+e^-e^+ beam shearing the vacuum

The microphysics of relativistic collisionless sheared flows is investigated in a configuration consisting of a globally neutral, relativistic $e^-e^+$ beam streaming through a hollow plasma/dielectric channel. We show through multidimensional PIC simulations that this scenario excites the Mushroom instability (MI), a transverse shear instability on the electron-scale, when there is no overlap (no contact) between the $e^-e^+$ beam and the walls of the hollow plasma channel. The onset of the MI leads to the conversion of the beam's kinetic energy into magnetic (and electric) field energy, effectively slowing down a globally neutral body in the absence of contact. The collisionless shear physics explored in this configuration may operate in astrophysical environments, particularly in highly relativistic and supersonic settings where macroscopic shear processes are stable

Exact solution for the energy density inside a one-dimensional non-static cavity with an arbitrary initial field state

We study the exact solution for the energy density of a real massless scalar field in a two-dimensional spacetime, inside a non-static cavity with an arbitrary initial field state, taking into account the Neumann and Dirichlet boundary conditions. This work generalizes the exact solution proposed by Cole and Schieve in the context of the Dirichlet boundary condition and vacuum as the initial state. We investigate diagonal states, examining the vacuum and thermal field as particular cases. We also study non-diagonal initial field states, taking as examples the coherent and Schrodinger cat states.Comment: 10 pages, 8 figure

Fermentation of xylose-rich substrates by the haloarchaeon halorhabdus utahensis towards high value-added bioproducts [Poster]

ABSTRACT: Research that focuses on the use of high value-added bioproducts for industrial applications is essential for the implementation of sustainable approaches forecasting a bio-based economy. The effective use of biomass feedstocks, particularly lignocellulosic materials, in large-scale applications will evolve from innovative research aimed at the development and implementation of biorefineries established for specific feedstocks. In this context, an important step is the concept of fractionating biomass into its core constituents (cellulose, hemicellulose and lignin) for further enhanced valorization. Contrary to the valorization of cellulose fraction, which has been extensively studied, there is a gap in the valorization of the hemicellulose fraction (xylose- rich substrate) towards bioproducts. In this context, the present work aims to explore the ability of the haloarchaeon Halorhabdus utahensis (DSM-12940) to ferment xylose (or xylose-rich substrates) to high added-value bioproducts, such as pigments, exopolysaccharides (EPS) and polyhydroxyalkanoates (PHAs).N/

As brandas de gado das Serras da Peneda e do Soajo (NW de Portugal)

Neste estudo são analisadas as brandas de gado do complexo montanhoso das Serras da Peneda e Soajo, situadas acima de 900 metros de altitude e com bom acesso, circunscritas ao Parque Nacional da Peneda-Gerês. Os resultados obtidos por análise geomorfológica e espacial, indicam que o local de edificação das brandas seguiu critérios comuns: todas têm disponibilidade de água, de pastagem espontânea, de proteção e boa exposição solar. Os cortelhos e bezerreiras enquadram-se no substrato granítico e utilizam os recursos locais sem afeiçoamento, designadamente lajes e blocos tabulares. Este é um património essencialmente cultural mas com ligações evidentes ao contexto geomorfológico, apresentando grande potencialidade no desenvolvimento territorial associado a atividades turísticas.The purpose of the study is the analys of shepherd’s shelters of the Peneda and Soajo Mountains, in the Peneda-Gerês National Park. Were selected those located above 900 meters and with good access. The results obtained from spatial and geomorphic analysis indicate that the criteria of choice for the edification of the shelters were similar. All of them have water availability, pasture spontaneous, protection, and good sun exposure. The shelters are built on the granite bedrock, mainly with slabs and blocks. They are a cultural heritage, close related with the geomorphological and geological characteristics of the area. These types of cultural and geomorphological heritage have great potential to implement tourism, having an important role to the sustainable rural development of the mountain region

Tribological behavior of bioactive multi-material structures targeting orthopedic applications

Acknowledgments This work was supported by Fundação para a Ciência e Tecnologia (FCT), Portugal through the grants SFRH/BD/140191/2018, SFRH/BD/ 128657/2017 and SFRH/BPD/112111/2015, the project PTDC/EMSTEC/ 5422/2014 and also by project NORTE 01-0145_FEDER-000018. Additionally, this work is supported by FCT with the reference project UID/EEA/04436/2019.The following study proposes a multi-material solution in which Ti6Al4V cellular structures produced by Selective Laser Melting are impregnated with bioactive materials (hydroxyapatite or β-tricalcium phosphate) using press and sintering technique. To assess the tribological response of these structures, an alumina plate was used as a counterpart in a flat-on-flat reciprocating sliding test. Ti6Al4V cellular structures impregnated with bioactive materials displayed the highest wear resistance when compared with the unreinforced structures. Among the bioactive structures, Ti6Al4V cellular structures impregnated with βTCP were the ones with higher wear resistance, having the lowest weight loss. Hence, these structures are promising multifunctional solutions for load-bearing applications by gathering suitable mechanical properties (strength and stiffness); bioactive properties and in addition an improved wear performance.info:eu-repo/semantics/publishedVersio

Avaliação das propriedades físicas do solo e ocorrência da anomalia "Soja Louca II" em sistemas de produção agrícola na Amazônia.

O objetivo deste estudo foi avaliar a relação de propriedades físicas do solo com a ocorrência da anomalia ?Soja Louca II?. Foi utilizado a cultivar de soja BRS Sambaíba em Sistema Plantio Convencional (SPC) e Sistema de Plantio Direto (SPD), com ou sem plantas de cobertura. Em SPD foram usadas como planta de cobertura Brachiaria ruziziensis, Brachiaria brizantha (cv. Piatã), Panicum sp. (cv. Massai) e Pousio. Para a avaliação dos atributos físicos do solo foram amostradas três repetições para cada bloco, para um total de nove sub amostras em profundidades 0-10; 10-20; 20-30 e 30-50 cm. Foram avaliadas gra- nulometria das partículas, densidade aparente e porosidade do solo. As avaliações de ?Soja Louca II? foram realizadas atribuindo percentagem de ocorrência da anomalia em cada parcela. Os tratamentos de manejo em SPD apresentaram maior densidade do solo, maior microporosidade e menor macroporosidade em relação ao tratamento em SPC. A cultura da soja implantada e conduzida em SPC apresentou menor valor de densidade do solo e menor incidência de ?Soja Louca II?. A cultura de soja, conduzida em cultivo mínimo (Pousio), propiciou maior ocorrência de ?Soja Louca II? em relação ao SPD e SPC. Há correlação positiva da ocorrência de ?Soja Louca II? com a densidade do solo, e negativa com a macroporosidade do solo, evidenciando a necessidade do bom manejo do SPD, para minimizar as perdas ligadas a esta anomaliabitstream/item/129787/1/CPAF-AP-2014-BPD-87-Soja-louca-versaofinal.pd