Methodology optimization and application for measurement of gaseous elemental mercury in the amazon atmosphere

The aim of this study was to optimize a semi-automatic methodology using commercial pure gold cartridges (Tekran Inc.) to quantify gaseous elemental mercury (GEM) in the Amazon atmosphere. The detection limit was 0.020 ± 0.006 ng Hg. This corresponds to detection limits varying from 0.2 to 0.4 ng Hg m-3, for field sample volumes ranging between 0.1 and 0.05 m³. The similarity between the 9 tested cartridges was evaluated. Under sampling flow rates varying between 0.4 and 2.0 L min-1 no difference among cartridges was observed. The maximum retention capacity of the cartridge (breakthrough) was not reached in experiments with flow rates of 1 or 2 L min-1, and with Hg concentration of 25 ng m-3 and maximum air volume of 150 L. Water condensation on the gold surface showed to be a problem, but that was solved by heating the sample cartridge at 60 ºC during sampling

Corrosion Grade on Anchor Rods of Guyed Transmission Towers Applying Machine Committee / Grau de Corrosão em Hastes de Âncora de Torres de Transmissão Guiadas Comitê de Aplicação de Máquinas

The use of guyed structures in electric power transmission lines is a growing practice because of their cost efficiency. However, the anchor systems are subject to corrosion, which can lead to their rupture and loss of tower support. Monitoring the evolution of the corrosion of the anchor rods by visual inspection is a destructive and costly method; therefore, there is considerable interest in developing methods and tools that are capable of generating a maintenance diagnosis of the system. This work aimed to propose a classification tool for guyed towers in terms of the corrosion degree by a machine committee with neural networks and applied it to the Paraiso-Açu line located in Rio Grande do Norte in Brazil. Thirty-eight samples were collected and 33 variables related to the soil corrosion along the line were analyzed. The targets for training the networks were obtained from the inspection of anchor rods taken from the field. A simplification of the problem's dimension was proposed by principal component analysis, describing the phenomenon with 6 variables instead of 33, simplifying the practical application by massively reducing the requirements for data sampling in the field. Several network typologies were trained and the best ones in terms of their generalist and specialist capacities were combined in a machine committee for the final proposal of this work. The classification obtained by the application of the committee for 10 towers was compared with the classification from non-destructive impulse reflectometry tests and showed an 80% correlation

Color discrimination is affected by modulation of luminance noise in pseudoisochromatic stimuli

Pseudoisochromatic stimuli have been widely used to evaluate color discrimination and to identify color vision deficits. Luminance noise is one of the stimulus parameters used to ensure that subject´s response is due to their ability to discriminate target stimulus from the background based solely on the hue between the colors that compose such stimuli. We studied the influence of contrast modulation of the stimulus luminance noise on threshold and reaction time color discrimination. We evaluated color discrimination thresholds using the Cambridge Color Test (CCT) at six different stimulus mean luminances. Each mean luminance condition was tested using two protocols: constant absolute difference between maximum and minimum luminance of the luminance noise (constant delta protocol, CDP), and constant contrast modulation of the luminance noise (constant contrast protocol, CCP). MacAdam ellipses were fitted to the color discrimination thresholds in the CIE 1976 color space to quantify the color discrimination ellipses at threshold level. The same CDP and CCP protocols were applied in the experiment measuring RTs at three levels of stimulus mean luminance. The color threshold measurements show that for the CDP, ellipse areas decreased as a function of the mean luminance and they were significantly larger at the two lowest mean luminances, 10 cd/m2 and 13 cd/m2, compared to the highest one, 25 cd/m2. For the CCP, the ellipses areas also decreased as a function of the mean luminance, but there was no significant difference between ellipses areas estimated at six stimulus mean luminances. The exponent of the decrease of ellipse areas as a function of stimulus mean luminance was steeper in the CDP than CCP. Further, reaction time increased linearly with the reciprocal of the length of the chromatic vectors varying along the four chromatic half-axes. It decreased as a function of stimulus mean luminance in the CDP but not in the CCP. The findings indicated that visual performance using pseudoisochromatic stimuli was dependent on the Weber´s contrast of the luminance noise. Low Weber´s contrast in the luminance noise is suggested to have a reduced effect on chromatic information and, hence, facilitate desegregation of the hue-defined target from the background.Fil: Cormenzana Méndez, Iñaki. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Laboratorio de Luminotecnia; ArgentinaFil: Martín, Andrés. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán. Instituto de Investigación en Luz, Ambiente y Visión. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Instituto de Investigación en Luz, Ambiente y Visión; Argentina. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Laboratorio de Luminotecnia; ArgentinaFil: Charmichael, Teaire L.. Christian Brothers University; Estados UnidosFil: Jacob, Mellina M.. Universidade Federal do Pará; BrasilFil: Lacerda, Eliza M. C. B.. Universidade Federal do Pará; BrasilFil: Gomes, Bruno D.. Universidade Federal do Pará; BrasilFil: Fitzgerald, Malinda E. C.. Christian Brothers University; Estados Unidos. University of Tennessee; Estados UnidosFil: Ventura, Dora F.. Universidade de Sao Paulo; BrasilFil: Silveira, Luiz C. L.. Universidade do Ceuma; Brasil. Universidade Federal do Pará; BrasilFil: O´donell, Beatriz Maria. Universidad Nacional de Tucumán. Facultad de Ciencias Exactas y Tecnología. Laboratorio de Luminotecnia; ArgentinaFil: Souza, Givago S.. Universidade Federal do Pará; Brasi

L-NAME treatment enhances exercise-induced content of myocardial heat shock protein 72 (Hsp72) in rats

Background/Aim: Nitric oxide (NO) modulates the expression of the chaperone Hsp72 in the heart, and exercise stimulates both NO production and myocardial Hsp72 expression. The main purpose of the study was to investigate whether NO interferes with an exercise-induced myocardial Hsp72 expression. Methods: Male Wistar rats (70-100 days) were divided into control (C, n= 12), L-NAME-treated (L, n= 12), exercise (E, n= 13) and exercise plus L-NAME-treated (EL, n= 20) groups. L-NAME was given in drinking water (700 mg. L-1) and the exercise was performed on a treadmill (15-25 m.min(-1), 40-60 min. day(-1)) for seven days. Left ventricle (LV) protein Hsp content, NOS and phosphorylated-NOS (p-NOS) isoforms were measured using Western blotting. The activity of NOS was assayed in LV homogenates by the conversion of [H-3] L-arginine to [H-3] L-citrulline. Results: Hsp72 content was increased significantly (223%; p < 0.05) in the E group compared to the C group, but exercise alone did not alter the NOS content, p-NOS isoforms or NOS activity. Contrary to our expectation, L-NAME enhanced (p < 0.05) the exercise-induced Hsp72 content (EL vs. C, L and E groups = 1019%, 548% and 457%, respectively). Although the EL group had increased stimulatory p-eNOS(Ser1177) (over 200%) and decreased inhibitory p-nNOS(Ser852) (similar to 50%) compared to both the E and L groups (p < 0.05), NOS activity was similar in all groups. Conclusions: Our results suggest that exercise-induced cardiac Hsp72 expression does not depend on NO. Conversely, the in vivo L-NAME treatment enhances exercise-induced Hsp72 production. This effect may be due to an increase in cardiac stress. Copyright (C) 2011 S. Karger AG, Basel275479486CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO - CNPQFUNDAÇÃO DE AMPARO À PESQUISA E INOVAÇÃO DO ESPÍRITO SANTO - FAPESsem informaçã

Erva-mate sombreada: Sipam "Sistemas tradicionais e agroecológicos de erva-mate na Floresta com Araucária, Brasil"

O cultivo, manejo e consumo da erva-mate (Ilex paraguariensis A. St. Hil.) ocorrem em várias re- giões da Argentina, Paraguai e Brasil. Entretanto, o centro-sul e sudeste do Paraná se destacam pela continuidade de práticas que constituem os sistemas tradicionais e agroecológicos de produ- ção de erva-mate em propriedades da agricultura familiar e comunidades tradicionais que ocorrem na presença da floresta, sendo, por isso, conhecidos também como erva-mate sombreada. Esses sistemas agroflorestais integram uma grande variedade de culturas alimentares e outros produtos florestais não madeireiros, tais como frutas nativas, milho, feijão, arroz e hortaliças, bem como a criação de animais. Apesar dos diferentes contextos e realidades dos atores sociais envolvidos na produção tradicional e agroecológica da erva-mate, os conhecimentos usados, o afeto pela floresta e as raízes profun- das das práticas culturais associadas a esses sistemas são similares e entrelaçados. Assim, os erveiros fazem parte de uma "comunidade de prática (CoP)" que conecta pequenos agricultores, comunidades tradicionais e indígenas que compartilham e ajudam a caracterizar a paisagem, e se reconhecem como um grupo diferenciado em relação à produção de erva-mate, cujas bases estão atreladas ao conhecimento e práticas locais e agroecológicas. Neste contexto, a erva-mate tem uma importância fundamental nas identidades ambientais e culturais dessas pessoas que lutam para dar continuidade ao sistema de produção e da floresta na qual ela ocorre. Com toda a diver- sidade de práticas, contextos e realidades na produção de erva-mate sombreada, percebe-se a existência de uma essência comum, baseada na relação direta entre o ser humano e as florestas. Considerando os Objetivos de Desenvolvimento Sustentável (ODS) da Organização das Nações Unidas (ONU), juntamente com as iniciativas da ONU e da Organização das Nações Unidas para a Alimentação e Agricultura (FAO) como a Década de Agricultura Familiar e a Década de Restauração dos Ecossistemas, os sistemas tradicionais de erva-mate oferecem uma oportunidade única para desenvolver ações que atendam às metas de tais programas, com destaque para os ODS 2, 8, 9, 11, 12, 15 e 17, fortalecendo as comunidades locais e protegendo e aumentando a cobertura flo- restal na região da Floresta com Araucária. Como benefícios adicionais, esses sistemas auxiliam no combate a dois dos maiores problemas ambientais em todo o mundo atualmente: perda de bio- diversidade e mudanças climáticas. Por meio das ações detalhadas neste documento focadas no entendimento, valorização e disseminação do conhecimento e das práticas e respectivos benefícios ambientais e socioambientais dos sistemas tradicionais de erva-mate, objetiva-se que tais sistemas se consolidem e se expandam como ferramentas de transformação social, econômica e ambiental. Neste contexto, a designação dos sistemas tradicionais de erva-mate como um Sistema Importante para o Patrimônio Agrícola Mundial (Sipam), iniciativa da Organização das Nações Unidas para a Alimentação e Agricultura (FAO), deverá contribuir sobremaneira para o reconhecimento dos sabe- res e das práticas dos sistemas tradicionais de erva-mate