Acidentes de viação em interseções de três ramos : estudo comparativo das formas funcionais do tráfego e das técnicas de modelação

Os acidentes de viação apresentam uma enorme carga social e económica, que é imposta à sociedade. Portanto, o conhecimento dos fatores que afetam a probabilidade de ocorrência dum acidente tem sido um domínio de investigação de há muitas décadas, o qual está longe de se esgotar. Assim, este trabalho estuda os acidentes ocorridos em 177 interseções de três ramos inseridas nas estradas nacionais – EN´s da região norte de Portugal (2005-2010), sendo apresentada uma contribuição inicial para o desenvolvimento de modelo de previsão de acidentes (MPA), em que considera-se quatro formas funcionais diferentes do tráfego nas aproximações das interseções e difundidas no estudo da sinistralidade. As técnicas de modelação utilizadas foram: (i) Modelos Lineares Generalizados – MLG; (ii) Equações de Estimação Generalizadas – EEG e (iii) Modelos Zero Inflacionados (ZIP e ZINB), com distribuições de Poisson e binomial negativa para a componente do erro aleatório. Obteve-se duas bases de dados, uma geral e uma derivada, com os acidentes e o tráfego das interseções, sendo uma para dados longitudinais (1062 observações) e outra para dados agregados. Como resultado apenas as EEG e os MLG forneceram modelos válidos, tendo sido identificada a melhor forma funcional em ambos os casos

The condensation of salicylaldehydes and malononitrile revisited : synthesis of new dimeric chromene derivatives

The reaction of salicylic aldehydes with malononitrile was reinvestigated, and the reaction pathway was followed by 1H NMR spectroscopy. A delicate control of the experimental conditions allowed the synthesis of 2-imino-2H-chromene-3-carbonitriles 1, (2-amino-3-cyano-4H-chromen-4-yl)malononitriles 2, 4-amino-5-imino-2,7-dimethoxy-5H-chromeno[3,4-c]pyridine-1-carbonitrile 12, and (4,5-diamino-1-cyano-1,10b-dihydro-2H-chromeno[3,4-c]pyridin-2-ylidene)malononitrile 13. Two novel 2-iminochromene dimers, with structures 8 and 9, were isolated and fully characterized. The activity of compound 8a on Aspergillus spp. growth and on ochratoxin A production was evaluated. The results of the bioassays indicate that compound 8a, applied at concentrations of 2 mM, totally inhibited the growth of the fungi tested. Ochratoxin A production by Aspergillus alliaceus was reduced by about 93% with a 200 μM solution of this compound. A moderate inhibitory effect was observed for the analogous structure 8b, and no inhibition was registered for compounds 2 and 1, used as synthetic precursors of the dimeric species 8

Post-harvest storage of papaya fruits coated with extracts of leaves and fruits of neem.

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Experimental methodology and analytical solution for cruciform ultrasonic fatigue Testing

As transportation and general machinery demand higher working speeds, reliability, and life spans [1], a higher life span characterisation method was required. In the middle of the 20th century, Mason devised a new fatigue testing method very different from the established ‘conventional’. The designated ultrasonic fatigue machine utilises resonance principles to achieve a considerably higher testing frequency. With Mason’s generally accepted 20 kHz standard reaching a billion cycles was made reliable. To make ultrasonic fatigue machines accessible and accepted, a trusted deterministic experimental methodology is necessary. Claude Bathias, the ultrasonic fatigue pioneer [1], brought ultrasonic fatigue testing (UFT) to the fatigue research world. His book details UTF methodology extensively for all uniaxial loading conditions [2]. Bathias et al. [3] have also shown piezoelectric fatigue testing machines in high and low temperatures, with R≠ -1 stress ratios and fretting. Considerable worldwide research has followed Bathias well described and methodically presented methodologies [4]–[6]. The first ‘conventional’ fatigue machines focused on pure uniaxial cyclical load, meaning one single direction load. Multiaxial stresses were later recognised as the leading dynamic stress state in machines and structures [7]. Thereafter, several different multiaxial testing methods came to fruition over the years, replicating the different cyclic loads. Just as ‘conventional’ fatigue transposed from uniaxial to multiaxial testing mechanisms, UFT developments will follow the same trend. Palin Luc et al. [8] induced a biaxial bending stress state with a carefully shaped disk. P. Costa et al. [9] created an altered ultrasonic setup capable of inducing a specimen in a tension-torsion stress state. In this study, a detailed methodology description with a proposed analytical solution is made to the already proven and working cruciform specimens created by D. Montalvão et al. [10]. Due to the cruciform deformation complexity, finite element analysis (FEA) was used to adjust Bathias analytical concepts

Synthesis and thermal behaviour of an amorphous solid polymer electrolyte

In this study the synthesis of an amorphous polymer network, poly[oxymethylene-oligo(oxyethylene)], designated as aPEO, is described. This polymer has been characterized by gel permeation chromatography, thermal analysis, conductivity measurements, evaluation of electrochemical stability and nuclear magnetic resonance spectroscopy. The synthetic procedure developed permits partial fractionation of the product of the polymerization reaction. This linear macromolecule appears to be a promising polymer for application in batteries and electrochromic devices since it provides access to an amorphous polymer structure with good mechanical properties and promising electrochemical behavior.Fundação para a Ciência e a Tecnologia (FCT

Occurrence of aflatoxin and filamentous fungi contamination in Brazil nuts feft inside the forest.

Brazil-nut is an important product for the Amazon economy, having as the main constraint for marketing, high levels of aflatoxin contamination, a toxic metabolite of potential carcinogenic effects produced by filamentous fungi. This work aimed to determine the occurrence of filamentous fungi and aflatoxin contamination during the post-harvest of brazil-nuts, as a mean to identify critical control points in the steps that precede processing

Toxicological Study Employing Repeated Doses of Garcinielliptone FC, a Polyisoprenylated-Benzophenone Isolated from Seed of Platonia Insignis Mart

The major constituent from the hexane extract of the seeds of P. insignis is GFC (garcinielliptone FC). Doses of 25, 50and 75 mg/kg of GFC were aseptically suspended in 0.05% Tween 80 dissolved in 0.9% saline (vehicle) and orally administered for30, 90 and 120 consecutive days to adult Swiss mice. In this work, the repeated oral administration, in animals of both sexes,demonstrates that this compound is not able to induce mortality and/or behavioral changes in adult mice. In addition, body weightgain, feed intake and disposal of excreta were not altered by the administration of this compound with repeated doses. Furthermore,no differences in weight and macroscopic structure of the brain, liver, kidney, lung, heart and spleen between groups of male andfemale adult mice were observed after treatment. During the periods of treatment, GFC produced no significant changes onhaematological and biochemical parameters in male and female mice treated with all doses used. The aim of this study was toinvestigate the toxicological potential of GFC through behavioral, hematological, biochemical and morphological parameters inanimals in order to ensure the safe use of Platonia insignis in folk medicine.Fil: Silva, Ana P.. Federal University of Piauí; BrasilFil: Filho, José Carlos C. L. S.. North Union of Parana; BrasilFil: da Costa Júnior, Joaquim S.. Federal Institute of Piauí; BrasilFil: Peláez, Walter José. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Faillace, Martín Sebastián. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto de Investigaciones en Físico-química de Córdoba. Universidad Nacional de Córdoba. Facultad de Ciencias Químicas. Instituto de Investigaciones en Físico-química de Córdoba; ArgentinaFil: Falcão Ferraz, Alexandre de B.. Lutheran University of Brazil; BrasilFil: David, Jorge M.. Institute Of Chemistry, Federal University Of Bahia; Brasil. Universidade Federal da Bahia; BrasilFil: Freitas, Rivelilson M.. Federal University of Bahia; Brasi

Assessment of Dimethoate in Olive Oil Samples Using a Dual Responsive Molecularly Imprinting-Based Approach

A new generation of advanced materials developed by molecular imprinting technology showing a stimuli-responsive functionality are emerging. The switchable ability to control the uptake/release of the target analyte by action of external stimulus combined with a remarkable selectivity and specificity, makes these functional materials very attractive for sample preparation purposes. In this work, the usefulness of a sample preparation tool for the selective enrichment/pre-concentration of dimethoate from olive oil spiked samples based on “tailor-made” dual responsive magnetic and photonic molecularly imprinted polymers as sorbents is explored. To achieve this goal, a smart molecularly imprinted polymer (MIP) possessing magnetic and photonic responsiveness was successfully synthesized, and its physico-chemical and morphological characterization was assessed. Further, the trace analysis of dimethoate in spiked olive oil samples was validated and successfully implemented using smart-MIPs as sorbents in the sample preparation step, with high recoveries (83.5 0.3%) and low detection limit (0.03 g mL 1)