Gluon saturation and the Froissart bound: a simple approach

At very high energies we expect that the hadronic cross sections satisfy the Froissart bound, which is a well-established property of the strong interactions. In this energy regime we also expect the formation of the Color Glass Condensate, characterized by gluon saturation and a typical momentum scale: the saturation scale $Q_s$. In this paper we show that if a saturation window exists between the nonperturbative and perturbative regimes of Quantum Chromodynamics (QCD), the total cross sections satisfy the Froissart bound. Furthermore, we show that our approach allows us to describe the high energy experimental data on $pp/p\bar{p}$ total cross sections.Comment: 6 pages, 5 figures. Includes additional figures, discussion and reference

Improving cost-efficiency for MPs density separation by zinc chloride reuse

The methodology used to extract and quantify microplastics (MPs) in aquatic systems are still not standardized. Salt saturated solutions, such as sodium chloride (NaCl), zinc chloride (ZnCl2) and/or sodium iodide (NaI), are normally added to separate dense plastics from aquatic samples. However, the most effective reagents are also the most expensive (e.g. ZnCl2 and NaI). To decrease this cost, a reuse process of the salt solutions should be applied. The reuse process has been widely investigated for the NaI solution neglecting the ZnCl2. Hence, the aim of this study was to present a simple methodology to reuse the ZnCl2 solution ensuring the efficiency of the product. Results of the present study showed that ZnCl2 solution could be reused at least five times maintaining an efficiency above 95 %. •The ZnCl2 reuse decreases the cost of the methodology.•The efficiency of ZnCl2 solution after five filtrations remains above 95 % (all polymers are detected and recovered).•The use of this salt solution is the most cost-effective methodology to isolate MPs from aquatic samples.publishe

Absolute Density Measures Estimation Functions with Very High Resolution Satellite Images

Assessment and monitoring of forest structure is frequently done with absolute density measures with field forest inventory data and expansion methods. The development of basal area and the number of trees estimation functions with data derived from very high spatial resolution satellite images enable their short-term and cost-effective evaluation, allowing also the estimation for the area not requiring extrapolation methods. The functions of basal area and the number of trees per hectare are based on crown cover obtained with very high spatial resolution satellite images for two evergreen oaks and umbrella pine. The three tree species are especially important in the agroforestry systems of the Mediterranean region. The linear functions fitted for pure stands of the three species and mixed stands of cork and holm oak and of cork oak and umbrella pine showed a better performance for basal area than for the number of trees per hectare. The inclusion of dummy variables for species composition improved the accuracy of the functions

Nomear objetos: uma questão de idade?

Poster apresentado no 2º Congresso Internacional de Saúde do Instituto Politécnico de Leiria, 9-10 Maio 2014, Leiria

Unha-de-gato, usos medicinais, ocorrência e conservação a campo no Amapá, Brasil.

O presente trabalho objetiva a coleta e formação a campo do banco das espécies medicinais Uncaria guianensis e U. tomentosa, assim como realizar o levantamento dos usos medicinais e da ocorrência das mesmas no Amapá. Sua distribuição é restrita ao ecossistema de floresta tropical úmida, tanto várzea como de terra firme, em solos distróficos do Grande Grupo do Latossolo Amarelo e/ou Gley Pouco Húmico e, clima Tropical do tipo Afi e Ami. Apresenta vasta gama de usos, no entanto, até o momento, sua exploração é extrativista e sem o uso de nenhum manejo que garanta sustentabilidade na sua exploração

Expressão de genes de resistência em resposta à infecção por nematóides.

A identificação de genes relacionados com a resistência de plantas a pragas e doenças é de grande importância para o entendimento dos mecanismos de defesa envolvidos durante o ataque de patógenos. Atualmente, vários desses genes, identificados em diferentes espécies vegetais, já foram caracterizados ao nível molecular e suas seqüências estão disponíveis em Bancos de Dados. Atualmente, com a conclusão do sequenciamento do Genoma Café, homólogos de genes de defesa tiveram suas seqüências estabelecidas. No entanto, estudos de genômica funcional são necessários para que o papel destes genes no mecanismo de resistência aos patógenos do café seja conhecido. Este trabalho tem como objetivo inicial caracterizar os mecanismos de defesa em café, através da identificação e avaliação da expressão de genes relacionados com a resistência a nematóides. Foram realizadas buscas de seqüências homólogas a genes de defesa no Banco de Dados do Genoma Café através do programa BLAST e foram identificados genes pertencentes a 12 categorias de genes de defesa. Em experimentos de infecção controlada, raízes de cafeeiros suscetíveis e resistentes foram infectadas pelo nematóide Meloidogyne exigua. Amostras de RNA extraído destas raízes serviram como molde para amplificação de transcritos correspondentes a 6 genes de resistência. Os resultados mostram que os genes avaliados neste estudo apresentam uma expressão basal em raízes infectadas pelo nematóide, sugerindo que a ativação da resposta de defesa é controlada por outras famílias de genes não testadas neste estudo

CLT for NESS of a reaction-diffusion model

We study the scaling properties of the non-equilibrium stationary states (NESS) of a reaction-diffusion model. Under a suitable smallness condition, we show that the density of particles satisfies a law of large numbers with respect to the NESS, with an explicit rate of convergence, and we also show that at mesoscopic scales the NESS is well approximated by a local equilibrium (product) measure, in the total variation distance. In addition, in dimensions $d \leq3$ we show a central limit theorem (CLT) for the density of particles under the NESS. The corresponding Gaussian limit can be represented as an independent sum of a white noise and a massive Gaussian free field, and in particular it presents macroscopic correlations.Comment: 33 page

Numerical modelling code based on the finite volume method in unstructured grids

In this work, the implementation employed in the new modeling code is described. It is based on the FVM with on a SIMPLE type scheme suitable for unstructured meshes.Fundação para a Ciência e a Tecnologia (FCT

Development of numerical tools to aid the design of complex geometry profile extrusion dies

The research team of this work is involved since the mid-nineties on the development of computational tools to aid the design of profile extrusion dies. Initially, the numerical code employed was based on structured meshes that limited its application to simple geometries. The work planned in this PhD programme comprises the development of a numerical modelling code able to deal with unstructured meshes and its application on the design of profile extrusion dies comprising complex cross sections. In its current state the numerical code under development is able to model de flow of generalized Newtonian fluids inside flow channels using unstructured meshes. This paper describes briefly the current state of the developed code and illustrates its application in a case study involving the design of a profile extrusion die comprising a complex cross section