Economic efficiency of free and open source software in the public sector: the example of Chile

Includes bibliography

Quantitative assessment of a free trade agreement between MERCOSUR and the European Union

Incluye Bibliografía

New label free CA125 detection based on gold nanostructured screen-printed electrode

This paper describes the optimisation and the analytical performances of a label-free impedimetric immunosensor for the detection of tumour marker CA125 based on gold nanoparticles modified screen-printed graphite electrode. Experimental conditions of each step for the developed immunosensor were studied and optimised. The immunosensor response varied linearly (r2 = 0.996) with antigen concentration between 0 and 100 U/mL. The estimated detection limit was 6.7 U/mL. The electrochemical immunosensor allowed unambiguous identification of CA125, while no significant non-specific signal was detected in the case of all negative controls. The analytical usefulness of the impedimetric immunosensor was finally demonstrated analysing serum samples. © 2012 Elsevier B.V. All rights reserved.

The Caribbean countries and the Free Trade Area of the Americas

Includes bibliography

Three-dimensional transient complex free surface flows: Numerical simulation of XPP fluid

In this paper we present a finite difference MAC-type approach for solving three-dimensional viscoelastic incompressible free surface flows governed by the eXtended Pom-Pom (XPP) model, considering a wide range of parameters. The numerical formulation presented in this work is an extension to three-dimensions of our implicit technique [Journal of Non-Newtonian Fluid Mechanics 166 (2011) 165-179] for solving two-dimensional viscoelastic free surface flows. To enhance the stability of the numerical method, we employ a combination of the projection method with an implicit technique for treating the pressure on the free surfaces. The differential constitutive equation of the fluid is solved using a second-order Runge-Kutta scheme. The numerical technique is validated by performing a mesh refinement study on a pipe flow, and the numerical results presented include the simulation of two complex viscoelastic free surface flows: extrudate-swell problem and jet buckling phenomenon. © 2013 Elsevier B.V.

Free tools and strategies for the generation of 3D finite element meshes: Modeling of the cardiac structures

The Finite Element Method is a well-known technique, being extensively applied in different areas. Studies using the Finite Element Method (FEM) are targeted to improve cardiac ablation procedures. For such simulations, the finite element meshes should consider the size and histological features of the target structures. However, it is possible to verify that some methods or tools used to generate meshes of human body structures are still limited, due to nondetailed models, nontrivial preprocessing, or mainly limitation in the use condition. In this paper, alternatives are demonstrated to solid modeling and automatic generation of highly refined tetrahedral meshes, with quality compatible with other studies focused on mesh generation. The innovations presented here are strategies to integrate Open Source Software (OSS). The chosen techniques and strategies are presented and discussed, considering cardiac structures as a first application context. © 2013 E. Pavarino et al.

The United States-Central American Free Trade Agreement: fiscal implications for the Central American countries

Includes bibliography

The impact of China’s incursion into the North American Free Trade Agreement (NAFTA) on intra-industry trade

China has become a major player in world trade. Although it has not signed any trade agreements with the countries of the North American Free Trade Agreement (NAFTA), China has been gaining ground as a supplier of goods, making vigorous inroads into this area. One of the dominant trends in economic integration has been the development of intra-industry trade, which has flourished in the nafta signatory countries. This paper focuses on the analysis of intra-industry trade in the context of this free trade area, where the production structure of the countries involved has changed significantly since trade liberalization, revealing the internationalization of production chains. Lastly, changes in the trade structure induced by the growing presence of China in the nafta region are captured. Trade within this area works like a radiated wheel, with the United States acting as the axis, while China, Canada and Mexico operate as the spokes.

Some mathematical aspects and scattering amplitudes in the pure spinor formalism

Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)

Immunodetection of Helicobacter sp. and the associated expression of ABO blood group antigens in the gastric mucosa of captive and free-living New World primates in the Amazon region

The histo-blood group ABH antigens were first described in humans. These antigens are only present on erythrocytes from great apes and humans, while in more primitive animals they are found in tissues and body fluids. The ABH antigens are mainly distributed in tissues exposed to the external environment and potentially serve as ligands for pathogens or inhibitors of tissue connections. The objective of this paper was two-fold: (i) to determine the presence of Helicobacter sp. in the gastric mucosa of 16 captive and 24 free-living New World monkeys and (ii) to evaluate the presence of histopathological alterations related to bacterial infection and the associated expression of ABH antigens in the tissue. Stomach tissues from 13 species of monkey were assessed using haematoxylin-eosin and modified Gram staining (Hucker) methods. An immunohistochemical analysis of the tissue revealed the presence of infectious bacteria that were characteristic of the genus Helicobacter sp. The results demonstrate that various species of monkey might be naturally infected with the Helicobacter sp. and that there is an increased susceptibility to infection. This study serves as a comparative analysis of infection between human and non-human primates and indicates the presence of a new species of Helicobacter.

Impact of the timing and duration of weed control on the establishment of a rubber tree plantation

A produção da seringueira é reduzida pelas plantas daninhas que competem por recursos ambientais; portanto, a época e duração do controle de plantas daninhas influencia a interferência das plantas daninhas. Os objetivos deste estudo foram: avaliar o crescimento de plantas de seringueira (Hevea brasiliensis), determinar o período crítico para controle das plantas daninhas e avaliar a recuperação do crescimento das seringueiras que conviveram com plantas daninhas por diferentes períodos de tempo após o plantio. Dois grupos de tratamentos foram estabelecidos em condições de campo, no primeiro ano de investigação: um grupo conteve períodos crescentes de infestação de plantas daninhas, enquanto o outro conteve períodos crescentes de controle das plantas daninhas, também incluindo uma testemunha livre de plantas daninhas e uma testemunha com infestação total de plantas daninhas. No segundo ano da investigação, as plantas daninhas foram totalmente controladas. Urochloa decumbens foi a planta daninha dominante (mais de 90% de cobertura). O crescimento da cultura foi grandemente reduzido devido à interferência de plantas daninhas. A altura de plantas decresceu mais rapidamente que qualquer outra característica. Altura de planta, massa seca de folhas e área foliar decresceram em 99%, 97% e 96%, respectivamente, e foram as características mais reduzidas. A altura de plantas também se recuperou mais rapidamente que qualquer outra característica quando o período de controle das plantas daninhas foi entendido. Contudo, a massa seca do caule aumentou em 750%, fazendo desta a característica mais recuperada. O período crítico para o controle de plantas daninhas foi entre 4 e 9½ meses após o plantio, no primeiro ano; contudo, as seringueiras mostraram expressiva recuperação do crescimento quando as plantas daninhas foram controladas ao longo do segundo ano.

Análise de marcadores culturais no par de obras Relato de um certo oriente e The tree of the seventh heaven

This paper presents some results of a study on culturally marked terms in a corpus composed by the Brazilian novel Relato de um certo oriente (1989), by Milton Hatoum, and its translation into English The tree of the seventh heaven, by Ellen Watson. For the analysis of culturally marked terms, we followed the interdisciplinary approach proposed by Camargo (2005, 2007) involving corpus-based translation studies (BAKER, 1993, 1995, 1996, 2000), and the investigations of cultural domains (NIDA, 1945; AUBERT, 1981, 2006). The methodology adopted in the present research required the software WordSmith Tools (SCOTT, 2007), which provides the necessary resources for the collection of data in a corpus of translated texts. The software tool called WordList was used for the selection of the most frequent words in the texts and also for the identification of the culturally marked terms. For the analysis of the culturally marked terms in both texts we used the software tool Concord. The results revealed that most of the culturally marked terms are inserted in the ecological domain, and the other terms are distributed in the domains of material, social and ideological culture, which reflects the theme of the book.

Preliminary in vitro and ex vivo evaluation of afzelin, kaempferitrin and pterogynoside action over free radicals and reactive oxygen species

Biological activities of flavonoids have been extensively reviewed in literature. The biochemical profile of afzelin, kaempferitrin, and pterogynoside acting on reactive oxygen species was investigated in this paper. The flavonoids were able to act as scavengers of the superoxide anion, hypochlorous acid and taurine chloramine. Although flavonoids are naturally occurring substances in plants which antioxidant activities have been widely advertised as beneficial, afzelin, kaempferitrin, and pterogynoside were able to promote cytotoxic effect. In red blood cells this toxicity was enhanced, depending on flavonoids concentration, in the presence of hypochlorous acid, but reduced in the presence of 2,20 -azo-bis(2-amidinopropane) free radical. These flavonoids had also promoted the death of neutrophils, which was exacerbated when the oxidative burst was initiated by phorbol miristate acetate. Therefore, despite their well-known scavenging action toward free radicals and oxidants, these compounds could be very harmful to living organisms through their action over erythrocytes and neutrophils.

On the Bhabha scattering for z=2 Lifshitz QED

In this paper, we compute and discuss the differential cross-section of the Bhabha scattering in the framework of the z = 2 Lifshitz quantum electrodynamics (QED). We start by constructing the classical solutions for the fermionic fields, in particular the completeness relations, and also derive the theory's propagators. Afterwards, we compute the photon exchange and pair annihilation contributions for the Bhabha's process, and upon achieving the results we establish the magnitude of the theory's free parameter by looking for small deviations of the QED tree results.

On the long standing issue of an R phi(2) coupling between gravity and a massless free scalar field

Using 2-body trees on a flat space background, it is shown that the actions A[g, φ] = (Latin small letter esh) d4x√-g [(R/2K) + (1/2)(gμν ∂μφ∂νφ + λRφ2)] and Ā[ḡ, φ̄] = (Latin small letter esh) d4x√ - ḡ [(R̄/2k) + (1/2) ḡμν∂μφ̄∂ νφ] describe the same theory at the tree-level in this case. We also demonstrate the quantum equivalence (at one-loop) of the barred and unbarred systems for λ == -1/6 (conformal coupling).