Ocorrência de um evento de condensação à superfície em área de pastagem na Amazônia

A condensação é uma variável indispensável para o entendimentode muitos processos hidrológicos e biológicos, principalmente naAmazônia. Dentro da estrutura do experimento Large Scale Biosphere-Atmosphere Experiment in Amazonia (LBA), a campanha Smoke,Aerosols, Clouds, Rainfall, and Climate (SMOCC) foi realizada no períodode setembro a novembro de 2002 no antigo sítio experimental doprojeto ABRACOS, Rondônia, com o objetivo de analisar, dentre outros,a formação e dissipação da condensação do vapor d´água a superfície.De acordo com resultados obtidos a formação da condensação éresultado do comportamento das variáveis meteorológicas que variam aolongo do período diurno\noturno, sendo que sua maior freqüência ocorreudurante o período noturno por apresentar condições propícias paraseu acontecimento. Para os eventos analisados nesse trabalho, observouseque sua formação e manutenção foram em função da intensidade dovento

Effect of yeast cell wall on the performance of broiler chickens intoxicated with aflatoxin B1

Micotoxinas são metabólitos secundários produzidos por diversos fungos filamentosos, tóxicos à animais e ao homem por contato, inalação e principalmente ingestão. Aflatoxinas são micotoxinas hepatotóxicas e carcinogênicas, produzidas principalmente pelos fungos Aspergillus flavus e A. parasiticus, e sua presença constitui grande preocupação para a avicultura mundial por problemas como diminuição da produtividade das aves e lesões de carcaça. Adsorventes à base de parede celular da levedura Saccharomyces cerevisiae, possuem glucomananos esterificadas, e são capazes de ligar-se eficientemente a diversas micotoxinas, como aflatoxinas, fumonisinas e zearalenona.   O objetivo do presente estudo foi o de avaliar o desempenho de um aditivo anti-micotoxinas (AAM) à base de parede de leveduras (PCL), em condição de intoxicação experimental por aflatoxina B1 (AFB1) em frangos de corte até os 21 dias de idade.  A adição de 1,012 mg kg-1 (ppm) de AFB1 na dieta dos frangos de corte no presente estudo foi capaz de alterar negativamente o peso vivo, ganho de peso e conversão alimentar a partir dos 14 dias de idade, e nas mesmas condições experimentais a adição do AAM (0,2%) à base de PCL reverteu tais efeitos. Mais estudos devem ser realizados acerca do assunto para melhor esclarecer o mecanismo de ação destes aditivos na produção animal.Mycotoxins are secondary metabolites produced by several filamentous fungi, which are toxic to animals and humans by contact, inhalation and ingestion mainly. Aflatoxins are hepatotoxic and carcinogenic mycotoxins produced mainly by Aspergillus flavus and A. parasiticus. Its presence is of great concern to the poultry industry due to problems such as decreased productivity and damage to the poultry carcass. Adsorbents based on the yeast cell wall of Saccharomyces cerevisiae have esterified glucomannans, and are able to adsorb several mycotoxins such as aflatoxins, fumonisins and zearalenone. The aim of this study was to evaluate the effect of a yeast cell wall (anti-mycotoxin additive) on the performance of broiler chickens intoxicated with aflatoxin B1 (AFB1 ) until 21 days old. The addition of 1.01 mg kg-1 (ppm) of AFB1 in the diet of broilers in this study could affect negatively body weight, weight gain and feed consumption after 7 days old, and under the same experimental conditions the yeast cell wall (0.2%) used as an anti-mycotoxin additive reversed such effects. More studies should be conducted to better clarify the mechanism of action of these additives in animal production.Fil: Keller, Kelly Moura. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Oliveira, A. A. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Almeida, T. X.. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Keller, Luiz Antonio Moura. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Queiroz, B. D.. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Nunes, L. M. T.. Universidad Federal Rural de Rio de Janeiro; BrasilFil: Cavaglieri, Lilia Reneé. Universidad Nacional de Río Cuarto. Facultad de Ciencias Exactas, Fisicoquímicas y Naturales. Departamento de Microbiología e Inmunología; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Rosa, Carlos Alberto da Rocha. Universidad Federal Rural de Rio de Janeiro; Brasi

Minerals and potentially toxic elements in corn silage from tropical and subtropical Brazil

Copyright: This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Our aim was to assess the mineral composition of corn silages produced in four states of Brazil: Goiás, Minas Gerais, Paraná, and Santa Catarina. In total, seventy-three samples were analyzed. Total element content was extracted by HNO3 and H2O2 microwave-assisted digestion, and inductively coupled plasma-mass spectrometry (ICP-MS) was used to determine concentration. Of the 31 elements analyzed (Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cs, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Rb, S, Se, Sr, Ti, Tl, U, V, and Zn), 21 had concentrations above equipment detection limits. No elements reached the maximum tolerable concentration, but concentrations of Ca (0.14-0.15%), Cu (3.4-5.6 mg kg-1), P (0.13-0.16%), S (0.06-0.08%), and Zn (13-19 mg kg-1) were below the adequate concentration for good nutritional balance. The strong and consistent correlation observed between Fe and Ti in silage samples indicated contamination by soil. Mean concentrations of Cu, Mn, Mo, P, S, and Zn were different among states, and canonic analyses successfully discriminate samples according to their state of origin. Minerals from corn silage should be considered when formulating balanced cattle diets. To ensure silage quality, farmers must adopt strategies that reduce contamination by soil during the ensiling process

The Pirata Program : history, accomplishments, and future directions

Author Posting. © American Meteorological Society, 2008. This article is posted here by permission of American Meteorological Society for personal use, not for redistribution. The definitive version was published in Bulletin of the American Meteorological Society 89 (2008): 1111–1125, doi:10.1175/2008BAMS2462.1.The Pilot Research Moored Array in the tropical Atlantic (PIRATA) was developed as a multinational observation network to improve our knowledge and understanding of ocean–atmosphere variability in the tropical Atlantic. PIRATA was motivated by fundamental scientific issues and by societal needs for improved prediction of climate variability and its impact on the economies of West Africa, northeastern Brazil, the West Indies, and the United States. In this paper the implementation of this network is described, noteworthy accomplishments are highlighted, and the future of PIRATA in the framework of a sustainable tropical Atlantic observing system is discussed. We demonstrate that PIRATA has advanced beyond a “Pilot” program and, as such, we have redefined the PIRATA acronym to be “Prediction and Research Moored Array in the Tropical Atlantic.

SORPTION OF S-TRIAZINES IN BRAZILIAN RAINFOREST SOILS

This research was conducted to evaluate the sorption of Ametryn, Atrazine, Simazine, Prometrine and Metamitron to soils from "Mata Atlântica" at Ubatuba region (Atlantic rainforest soils), employing the batch equilibrium approach. The herbicides were weakly retained in soils with low soil organic matter (SOM) content and thus presenting high potential to water contamination. All herbicides have shown high Koc at Typic Humaquepts soil, the higher in SOM content. The sorption isotherms for the herbicides at Typic Humaquepts soil suggested specific interactions between herbicides and SOM probably with partial protonation of herbicides followed by ion-exchange processes and/or hydrogen bonding formation of hydroxyl groups on the SOM surface.Esta pesquisa foi conduzida para avaliar a sorção de ametrina, atrazina, simazina, prometrina e metamitron em solos de Mata Atlântica na região de Ubatuba, empregando-se o método em batelada. Os herbicidas foram fracamente retidos em solos com baixo teor de matéria orgânica (MO) e, portanto, apresentaram elevado potencial de contaminação da água. Todos os herbicidas mostraram alto valor de Koc em solos da classe Gleissolo Melânico Distrófico, que contém o teor mais elevado de MO. As isotermas de sorção dos herbicidas no Gleissolo Melânico Distrófico sugerem interações específicas entre os herbicidas e a MO, provavelmente com protonação parcial dos herbicidas seguida por processos de troca-iônica e/ou formação de pontes de hidrogênio dos grupos hidroxila sobre a superfície da MO

Pathogenicity and aggressiveness of Colletotrichum gloeosporioides isolates in ornamental pepper

Anthracnose, a disease caused by fungi of the Colletotrichum genus, affects many crops, including ornamental plants. This study aimed at evaluating the pathogenicity and aggressiveness of the Colletotrichum gloeosporioides Penz. (Sacc.) isolates Cg1 (papaya), Cg2 (guava) and Cg3 (mango) in the ornamental pepper varieties Stromboli, Etna and Pirâmide, during two different periods (July/August and November/December 2013). The fungi pathogenicity and the severity of plant symptoms were assessed using a grading scale. The three C. gloeosporioides isolates were pathogenic to the three ornamental pepper varieties studied, exhibiting different levels of aggressiveness among them. The environmental conditions influenced the isolates aggressiveness, with the most severe symptoms observed in the second assessment period