372 research outputs found

    Effective Microorganisms: Myth or reality?

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    Th e increase in population has lead to intensifi cation of agricultural systems. Due to the use of pesticides the productivity of agricultural systems has increased but environmental deterioration and unsustainable systems are the consequences of these ways of management. Th e environmentally friendly Eff ective Microorganisms (EM) technology claims an enormous amount of benefi ts (claimed by the companies). Th e use of EM as an addictive to manure or as a spray directly in the fi elds may increase the microfauna diversity of the soil and many benefi ts are derived from that increase. It seems that suffi cient information is available about this new technology. Th e aim of this project is to make an analysis of the literature about EM and answer the following questions: 1) how much is known about EM?, 2) how much research is done on EM?, 3) what are the principals of EM?, what are the socio-economic implications of EM?. We want to answer these questions in order to publish the facts about EM and its socio-economic implications.Th e increase in population has lead to intensifi cation of agricultural systems. Due to the use of pesticides the productivity of agricultural systems has increased but environmental deterioration and unsustainable systems are the consequences of these ways of management. Th e environmentally friendly Eff ective Microorganisms (EM) technology claims an enormous amount of benefi ts (claimed by the companies). Th e use of EM as an addictive to manure or as a spray directly in the fi elds may increase the microfauna diversity of the soil and many benefi ts are derived from that increase. It seems that suffi cient information is available about this new technology. Th e aim of this project is to make an analysis of the literature about EM and answer the following questions: 1) how much is known about EM?, 2) how much research is done on EM?, 3) what are the principals of EM?, what are the socio-economic implications of EM?. We want to answer these questions in order to publish the facts about EM and its socio-economic implications

    Quark-hybrid matter in the cores of massive neutron stars

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    Using a nonlocal extension of the SU(3) Nambu-Jona-Lasinio model, which reproduces several of the key features of quantum chromodynamics, we show that mixed phases of deconfined quarks and confined hadrons (quark-hybrid matter) may exist in the cores of neutron stars as massive as around 2.1M ⊙. The radii of these objects are found to be in the canonical range of ∼12-13 km. According to our study, the transition to pure quark matter does not occur in stable neutron stars, but is shifted to neutron stars which are unstable against radial oscillations. The implications of our study for the recently discovered, massive neutron star PSR J1614-2230, whose gravitational mass is 1.97±0.04M⊙, are that this neutron star may contain an extended region of quark-hybrid matter at it center, but no pure quark matter.Facultad de Ciencias Astronómicas y Geofísica

    Characterisation of the progression of salts in walls of earthen architecture heritage

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    Two hundred years (1750–1950) of earthen architecture represents an important period of construction in the central region of Portugal. Earthen architecture is usually built close to the coast or to rivers and placed in sandy ground. The impact of rising damp is a general problem and efflorescences are a common cause of damage decay. This problem was studied in a building with two types of earthen construction, adobe masonry walls and formed masonry walls. The aim of this research was to characterise the conditions for the appearance and phase transitions of thénardite and mirabilite, and determine how to prevent progression of salt effects in the two types of wall to support future conservation measures. Laboratory capillarity and porosimetry tests with dolomitic air lime mortar and hygrothermal monitoring were pursued along with in situ tests. Visual assessment showed that the progression of salts depends on the composition of the earthen materials. To understand these differences, all crystalline solid phases were analysed by powder X-ray diffraction, and building interior hygrothermal conditions were monitored. An investigation into the influence of surface lime water painting and sacrificial mortar application on the crystallisation of sodium sulfates concluded that these also depend on the wall's composition. Data allowed us to conclude that inside the building the temperature and humidity [relative humidity (RH = 100 pw/p°w > 70)] conditions led to the adobe breakdown by the fast conversion from thénardite to mirabilite. Therefore, contact with wet atmospheres should be avoided and interior hygrothermal conditions should be controlled. Laboratory and in situ tests showed that the environmental conditions of the spaces had effects on the results. The results contribute to understanding of the salt progression and pattern of decay, as well as supporting future recommendations for building conservation, based on the identification of environmental conditions proper to their occurrence.publishe

    Effective dielectric constant of top grounded coplanar waveguide on liquid crystal superstrate

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    AbstractThe effective dielectric constant of the top grounded coplanar waveguide with a liquid crystal (LC) superstrate for phase shifting applications is investigated in the frequency range of 30–60 GHz. Two nematic LC mixtures, namely E7 and MDA‐00‐3506, are used as the superstrate. The measurements show that MDA‐00‐3506 offers higher values of phase shift per millimeter than its E7 counterpart. In particular, the MDA‐00‐3506 provides 3.14°/mm, whereas E7 gives 2.79°/mm at 60 GHz. The results of the dielectric constants from measurement and computer modeling are found to agree to within 5%. For the modeling, a comprehensive finite element package predicting the local alignment of LC molecules and effective dielectric constant at different bias voltages and frequencies are used. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1416–1418, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27564</jats:p

    Metals from human activities in a coastal Lagoon Saltmarsh - Sediment toxicity and phytoremediation by Sarcocornia fruticosa

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    Anthropogenic pressure on coastal areas has been increasing in the last decades, threating the saltmarshes and the ecosystem services they provide. Sarcocornia fruticosa can have an important role in sequestration of metals from human activities. This study evaluated the effect of metal toxicity in saltmarsh sediment (measured by Ecological Risk Index-ERI) on S. fruticosa ability to metal (Cd, Cr, Ni, Pb and Zn) remediation (Enrichment Factor and metal translocation). The impact of urbanization was studied through the metal loads on stormwaters during two main rainfall events, and the industrial impact was assessed through data analyses in a saltmarsh area influenced by a stream that receives industrial runoffs. The S. fruticosa response on metal remediation was affected by ERI. In more polluted locations, retained metals on roots and prevented the most toxic (Cd and Pb) from reaching the aerial organs, avoiding tissues death and metal remobilisation to the saltmarsh. Meanwhile, in rhizosediments with conditions to high metal bioavailability, S. fruticosa transported Cd and Pb to aerial organs, but used the Zn translocation to decrease their toxicity. This halophyte resilience is important to saltmarsh metal sequestration in high toxicity conditions, and allows the maintenance of other ecosystem services, contributing to the environmental protection and public health.info:eu-repo/semantics/publishedVersio

    First Comparative Transcriptomic Analysis of Wild Adult Male and Female Lutzomyia longipalpis, Vector of Visceral Leishmaniasis

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    Leishmaniasis is a vector-borne disease with a complex epidemiology and ecology. Visceral leishmaniasis (VL) is its most severe clinical form as it results in death if not treated. In Latin America VL is caused by the protist parasite Leishmania infantum (syn. chagasi) and transmitted by Lutzomyia longipalpis. This phlebotomine sand fly is only found in the New World, from Mexico to Argentina. However, due to deforestation, migration and urbanisation, among others, VL in Latin America is undergoing an evident geographic expansion as well as dramatic changes in its transmission patterns. In this context, the first VL outbreak was recently reported in Argentina, which has already caused 7 deaths and 83 reported cases. Insect vector transcriptomic analyses enable the identification of molecules involved in the insect's biology and vector-parasite interaction. Previous studies on laboratory reared Lu. longipalpis have provided a descriptive repertoire of gene expression in the whole insect, midgut, salivary gland and male reproductive organs. Nevertheless, the study of wild specimens would contribute a unique insight into the development of novel bioinsecticides. Given the recent VL outbreak in Argentina and the compelling need to develop appropriate control strategies, this study focused on wild male and female Lu. longipalpis from an Argentine endemic (Posadas, Misiones) and a Brazilian non-endemic (Lapinha Cave, Minas Gerais) VL location. In this study, total RNA was extracted from the sand flies, submitted to sequence independent amplification and high-throughput pyrosequencing. This is the first time an unbiased and comprehensive transcriptomic approach has been used to analyse an infectious disease vector in its natural environment. Transcripts identified in the sand flies showed characteristic profiles which correlated with the environment of origin and with taxa previously identified in these same specimens. Among these, various genes represented putative targets for vector control via RNA interference (RNAi).Facultad de Ciencias Exacta

    Ausência de associação entre indicadores de anemia ao nascimento e crescimento de prematuros

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    OBJECTIVE: To assess the association between iron status at birth and growth of preterm infants. METHODS: Ninety-five premature babies (26 to 36 weeks of gestational age) born from July 2000 to May 2001 in a public hospital in Rio de Janeiro, Southeastern Brazil, were followed up for six months, corrected by gestational age. Iron measurements at birth were available for 82 mothers and 78 children: hemoglobin, hematocrit, mean corpuscular volume and plasma iron. All children received free doses of iron supplement (2 mg/kg/day) during the follow-up period and up to two years of age. Multivariate linear regression analyses with repeated measurements were performed to assess factors associated to linear growth. RESULTS: Growth was more pronounced up to 40 weeks of gestational age, increasing about 1.0 cm/week and then slowing down to 0.75 cm/week. The multivariate analysis showed growth was positively associated with birth weight (0.4 cm/100 g; pOBJETIVO: Avaliar a associação entre indicadores de anemia no nascimento e o crescimento de prematuros. MÉTODOS: Crianças prematuras (26-36 semanas de idade gestacional) (n=95), nascidas de julho de 2000 a maio de 2001, em hospital público do Rio de Janeiro, foram seguidas por seis meses, corrigidos pela idade gestacional. Foram obtidos em 82 mães e 78 crianças os indicadores de anemia: hemoglobina, hematócrito, volume corpuscular médio e ferro plasmático. Os prematuros receberam suplemento de ferro (2 mg/kg/dia) durante o seguimento. Análises de regressão linear multivariadas, com medidas repetidas, avaliaram os fatores associados ao crescimento linear. RESULTADOS: O crescimento dos prematuros foi mais acentuado até as 40 semanas de idade gestacional, com aumento de aproximadamente 1,0cm/semana. Após essa fase, o crescimento foi de 0,75 cm/semana. Na análise multivariada o crescimento associou-se positivamente com o peso ao nascer (0,4 cm/100 g de peso ao nascer;

    Four tops for LHC

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    We design a search strategy for the Standard Model t¯tt¯tproduction at the LHC in the same-sign dilepton and trilepton channels. We study different signal features and, given the small expected number of signal events, we scrutinize in detail all reducible and irreducible backgrounds. Our analysis shows that by im-posing a basic set of jet and lepton selection criteria, the SM pp→t¯tt¯tprocess could be evidenced in the near future, within Run-II, when combining both multi-lepton search channels. We argue that this search strategy should also be used as a guideline to test New Physics coupling predominantly to top-quarks. In particular, we show that a non-resonant New Physics enhancement in the four-top final state would be de-tectable through this search strategy. We study two top-philicsimplified models of this kind, a neutral scalar boson and a Z0, and present current and future exclusion limits on their mass and couplings.Instituto de Física La Plat

    Quantifying instabilities in Financial Markets

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    Financial global crisis has devastating impacts to economies since early XX century and continues to impose increasing collateral damages for governments, enterprises, and society in general. Up to now, all efforts to obtain efficient methods to predict these events have been disappointing. However, the quest for a robust estimator of the degree of the market efficiency, or even, a crisis predictor, is still one of the most studied subjects in the field. We present here an original contribution that combines Information Theory with graph concepts, to study the return rate series of 32 global trade markets. Specifically, we propose a very simple quantifier that shows to be highly correlated with global financial instability periods, being also a good estimator of the market crisis risk and market resilience. We show that this estimator displays striking results when applied to countries that played central roles during the last major global market crisis. The simplicity and effectiveness of our quantifier allow us to anticipate its use in a wide range of disciplines.Fil: Gonçalves, Bruna Amin. Centro Federal de Educação Tecnológica de Minas Gerais. Programa de Pós Graduação em Modelagem Matemática e Computacional; BrasilFil: Carpi, Laura. Universidad Politécnica de Catalunya; EspañaFil: Rosso, Osvaldo Aníbal. Universidade Federal de Alagoas; Brasil. Hospital Italiano. Departamento de Informática En Salud.; Argentina. Universidad de Los Andes.; ChileFil: Ravetti, Martín G.. Universidade Federal de Minas Gerais; BrasilFil: Atman, A. P. F.. Centro Federal de Educação Tecnológica de Minas Gerais. Programa de Pós Graduação em Modelagem Matemática e Computacional; Brasi

    Molecular Techniques for Dicistrovirus Detection without RNA Extraction or Purification

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    Dicistroviridae is a new family of small, nonenveloped, and +ssRNA viruses pathogenic to both beneficial arthropods and insect pests as well. Triatoma virus (TrV), a dicistrovirus, is a pathogen of Triatoma infestans (Hemiptera: Reduviidae), one of the main vectors of Chagas disease. In this work, we report a single-step method to identify TrV, a dicistrovirus, isolated from fecal samples of triatomines. The identification method proved to be quite sensitive, even without the extraction and purification of RNA virus.Centro de Estudios Parasitológicos y de Vectore
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