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Search Results: 1 - 10 of 315964 matches for " CAMARGO Plínio B. de "
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Biomonitoring of Pb and Cd in two impacted watersheds in Southeast Brazil, using the freshwater mussel Anodontites trapesialis (Lamarck, 1819) (Bivalvia : Mycetopodidae) as a biological monitor
Tomazelli Andréa C.,Martinelli Luiz A.,Avelar Wagner E. P.,Camargo Plínio B. de
Brazilian Archives of Biology and Technology , 2003,
Abstract: Studies were carried out to investigate the contamination of Piracicaba and Mogi-Gua u River basins (S o Paulo State, Southeastern, Brazil) for heavy metals (Cd and Pb), using the limnic bivalve Anodontites trapesialis as a biological monitor. The results showed that the concentrations of Pb were higher than the control group in both basins, showing the bioavailability of this non-essential element in the basins. The concentrations were higher in the Mogi-Gua u than in the Piracicaba basin, and in the slightly contaminated sites in both basins. There was no correlation between the degree of human impact and Cd and Pb concentrations, it was not possible to infer about concentrations of these heavy metals in the bivalves based only in a broad evaluation of human impact.
Análise da adultera o de méis por a úcares comerciais utilizando-se a composi o isotópica de carbono
Ciência e Tecnologia de Alimentos , 1999,
Abstract: O mel é um alimento apreciado por seu sabor característico e pelo seu considerável valor nutritivo. Devido a oferta do produto ser menor que a procura, seu pre o é relativamente alto, incentivando sua adultera o. Geralmente, a adultera o do mel é feita através da adi o de a úcares comerciais, derivados de cana-de-a úcar e milho. Como essas plantas têm uma composi o isotópica do carbono distinta das plantas utilizadas pelas abelhas como fonte de néctar (flores silvestres, citros e eucaliptos), é possível utilizar a composi o isotópica do carbono de amostras de mel para se avaliar a adultera o desse produto por a úcares comerciais oriundos da cana e do milho. Foram analisadas amostras de plantas pertencentes ao ciclo fotos-sintético C3, subprodutos de plantas C4 (a úcares comerciais) e 61 amostras de mel obtidas no mercado. As plantas C3 analisadas apresentaram valores de d13C de -28,9±1,1? (n=8), enquanto os a úcares apresentaram valores de -11,1±0,7? (n=3). Das 61 amostras de mel analisadas, cerca de 8% (5 amostras) tiveram sinais claros de adultera o. A amostra de número 34 teve um valor igual a -12,9?, indicando que a úcar puro de cana-de-a úcar ou milho estaria sendo comercializado como mel. As amostras 13, 14, 33 e 54 apresentaram valores iguais a -21,0; -19,9; -21,9 e -17,6?, respectivamente. Esses valores indicam também adi o de a úcares de cana-de-a úcar ou milho, no entanto em menor propor o. A metodologia testada neste trabalho foi aprovada como um método simples, confiável e complementar aos métodos químicos e físicos convencionais visando detectar adultera o de mel.
Identifica??o de mudan?as florestais por 13C e 15N dos solos da Chapada do Araripe, Ceará
Mendon?a, Luiz A. R.;Frischkorn, Horst;Santiago, Marlúcia F.;Camargo, Plínio B. de;Lima, José O. G. de;Mendes Filho, Josué;
Revista Brasileira de Engenharia Agrícola e Ambiental , 2010, DOI: 10.1590/S1415-43662010000300012
Abstract: the organic matter (om) of soils can be used as an auxiliary tool for the identification of past vegetation. in the floresta nacional do araripe and its surroundings, on top of the araripe plateau, a study was made using measurements of d13c and d15n of soil om in order to (i) assess present day values for these parameters; (ii) to analyse natural variations of d13c in soils from different formations of forest; (iii) and to indicate forest decline. it was found that soils from (at present) protected areas, the om of which exhibits c3 type d13c of the present vegetation in surface samples but of the c3-c4 type in depth, correspond to ecosystems anthropized in the past through agriculture. soils maintaining d13c of the c3 type throughout the entire profile refer to ecosystems anthropized through non-agricultural exploitation. "caatinga" samples exhibit a d15n profile that indicates a soil more mineralized and with less om, whereas reforested preserved areas show recovery of om.
Análise da adultera??o de méis por a?úcares comerciais utilizando-se a composi??o isotópica de carbono
ROSSI, Nádia F.;MARTINELLI, Luiz A.;LACERDA, Tais H.M.;CAMARGO, Plínio B. de;VICTóRIA, Reynaldo L.;
Ciência e Tecnologia de Alimentos , 1999, DOI: 10.1590/S0101-20611999000200008
Abstract: honey is a known product for its nutritional value. considering that offer is smaller than the market demand, honey is relatively expensive. this fact contribute to the incentive of its adulteration by commercial sugars derived from sugar cane and corn. as these plants have a distinct stable carbon isotope composition than plants commonly used by bees as sources of nectar, it is possible to use the stable carbon isotope composition of honey to detect addition of commercial sugar cane and corn sugars. in this study we analyzed samples of c3 plants commonly used by bees, subproducts of c4 plants, and 61 samples of honey. the d13c of c3 plants values had on average of -28.9±1.1? (n=8), while the commercial sugars had an average value of -11.1±0.7? (n=3). approximately 8% (5 samples) of the 61 samples analyzed had d13c values that clearly indicated the addition of commercial sugars (adulteration). the sample number 5 had a d13c valor equal to -12.9?, indicating that it was all made of commercial sugars. the samples numbers 13, 14, 33, and 54 had values equal to -21.0, -19.9, -21.9 and -17.6?, respectively. these values also indicated the addition of commercial sugars. the methodology used in this study proved to be a valuable and simple complement to the conventional chemical and physical methods normally used to detect honey adulteration.
Isotopic signatures (δ 13C and δ15N) of muscle, carapace and claw in Phrynops geoffroanus (Testudines: Chelidae)
Marques, Thiago S.;Tassoni-Filho, Maurício;Ferronato, Bruno O.;Guardia, Isabela;Verdade, Luciano M.;Camargo, Plínio B. de;
Zoologia (Curitiba) , 2011, DOI: 10.1590/S1984-46702011000300016
Abstract: the isotopic composition ( δ13c and δ 15n) of muscle, carapace and claw was determined from six wild individuals of phrynops geoffroanus (schweigger, 1812) in order to verify the variation between those tissues. the mean values of δ13c e δ 15n were, respectively, -19.48 ± 0.81‰ (-20.8 - -18.64‰) and 7.23 ± 0.67‰ (6.49 - 8.3‰) for muscle, -16.52 ± 0.98‰ (-17.88 - -15.43‰) and 7.29 ± 0.54‰ (6.74 - 7.97‰) for carapace and -18.57 ± 0.97‰ (-19.97 - -17.26‰) and 4.36 ± 0.33‰ (3.93 - 4.79‰) for claw. we found a significant difference for the tissues evaluated for both δ13c and δ15n. muscle and claw were statistically similar and more depleted in 13c than the carapace. nonetheless, claw was more depleted in 15n than muscle and carapace tissues. these results are likely related to differences in metabolic processes involved on each tissue formation. the description of the isotopic signatures variation in p. geoffroanus tissues provides a baseline for future investigations on the diet reconstruction of this species when more than one tissue is involved.
Biomonitoring of Pb and Cd in two impacted watersheds in Southeast Brazil, using the freshwater mussel Anodontites trapesialis (Lamarck, 1819) (Bivalvia : Mycetopodidae) as a biological monitor
Tomazelli, Andréa C.;Martinelli, Luiz A.;Avelar, Wagner E. P.;Camargo, Plínio B. de;Fostier, Anne-Helene;Ferraz, Epaminondas S. B.;Krug, Francisco J.;Santos Júnior, Dário;
Brazilian Archives of Biology and Technology , 2003, DOI: 10.1590/S1516-89132003000400022
Abstract: studies were carried out to investigate the contamination of piracicaba and mogi-gua?u river basins (s?o paulo state, southeastern, brazil) for heavy metals (cd and pb), using the limnic bivalve anodontites trapesialis as a biological monitor. the results showed that the concentrations of pb were higher than the control group in both basins, showing the bioavailability of this non-essential element in the basins. the concentrations were higher in the mogi-gua?u than in the piracicaba basin, and in the slightly contaminated sites in both basins. there was no correlation between the degree of human impact and cd and pb concentrations, it was not possible to infer about concentrations of these heavy metals in the bivalves based only in a broad evaluation of human impact.
Isótopos estáveis e produ??o de bebidas: de onde vem o carbono que consumimos?
Oliveira, Ana Cristina B.;Salimon, Cleber I.;Calheiros, Débora Fernandes;Fernandes, Fernando Antonio;Vieira, Ivan;Charbel, Luiz Fernando;Pires, Luiz Fernando;Salom?o, Marcos S.M.B.;Nogueira, Sandra Furlan;Vieira, Simone;Moreira, Marcelo Zacharias;Martinelli, Luiz Ant?nio;Camargo, Plínio Barbosa de;
Ciência e Tecnologia de Alimentos , 2002, DOI: 10.1590/S0101-20612002000300015
Abstract: we used the carbon isotopic composition (d13c) to determine the botanical origin (whether c3 or c4) of coffee, wine, beer and vodka samples from different brands and origins commercialized in brazil. only one coffee sample showed a d13c typical of a mixture with c4 plants (d13c -16.2‰). the brazilian wine samples varied from d13c -25.1 to -18.6‰, indicating the presence of carbon from c4 plants in samples with greater values, while the imported wine showed d13c characteristic of c3 plants (-27.1 and -26.3‰). imported vodka also showed d13c typical of c3 plants (-26.4 and -23.9‰), while brazilian counterparts were typically made from c4 plants (-12.8 to -11.8‰), except for one sample (23,1‰). most of the imported beers showed more negative d13c (-27.3 to -20.7‰) than did the brazilian beers (-25.9 to -18.4‰). these results demonstrate the method's efficiency for tracing the carbon origin and determining the extent of blending in beverages.
Simula o dos efeitos das mudan as do uso da terra na dinamica de carbono no solo na bacia do rio Piracicaba
Pesquisa Agropecuária Brasileira , 2000,
Abstract: Neste trabalho teve-se como objetivo testar o modelo CENTURY para simular os efeitos das mudan as de uso da terra nos teores de carbono no solo e na produ o primária líquida na bacia do rio Piracicaba, SP. O modelo foi parametrizado e as simula es foram realizadas considerando-se áreas de florestas, pastagens e cana-de-a úcar, dada a sua importancia econ mica. Os resultados obtidos indicaram que a altera o do uso/cobertura do solo provoca a diminui o do estoque de carbono do solo. As simula es realizadas na transi o de uma floresta para cana-de-a úcar indicaram um decréscimo de 28% no estoque de carbono nos primeiros 12 anos, e diminui o de 42% com 50 anos de cultivo do solo com essa gramínea. Na simula o da transi o de uma floresta para pasto, seguida do cultivo da cana-de-a úcar, verificou-se que na primeira mudan a (floresta-pastagem) a perda de carbono foi de 24%, enquanto na segunda altera o (pastagem-cana) a perda foi de 22%. Com rela o à produ o primária, os resultados obtidos de floresta (6,6 t ha-1 ano-1), cana-de-a úcar (77, 82, 80 t ha-1 ano-1) e pasto (6,5 t ha-1 ano-1), mostraram-se similares aos valores observados no campo por outros autores.
Ana Paula Madeira Di Beneditto,Vanessa Trindade Bittar,Carlos Eduardo de Rezende,Plínio Barbosa Camargo
Neotropical Ichthyology , 2013,
Abstract: This study applies total mercury (THg) concentration and stable isotope signature (δ15N and δ13C) to evaluate the trophic status and feeding ground of Trichiurus lepturus during its ontogeny in northern Rio de Janeiro, south-eastern Brazil. The trophic position of T. lepturus is detected well by THg and δ15N as the sub-adult planktivorous specimens are distinct from the adult carnivorous specimens. The δ13C signatures suggest a feeding ground associated with marine coastal waters that are shared by fish in different ontogenetic phases. The diet tracers indicated that the fish feeding habits do not vary along seasons of the year, probably reflecting the prey availability in the study area. This fish has economic importance and the concentration of THg was compared to World Health Organization limit, showing that the adult specimens of T. lepturus are very close to the tolerable limit for safe regular ingestion. Este estudo utilizou a concentra o de mercúrio total (THg) e a assinatura isotópica (δ15N e δ13C) para avaliar a posi o trófica e a área de alimenta o de Trichiurus lepturus durante sua ontogenia no norte do Rio de Janeiro, sudeste do Brasil. A posi o trófica de T. lepturus foi bem detectada pelo THg e δ15N com os espécimes sub-adultos planctívoros distintos dos espécimes adultos carnívoros. As assinaturas de δ13C sugerem uma área de alimenta o associada a águas marinhas costeiras que s o compartilhadas por peixes em diferentes fases ontogenéticas. Os tra adores de dieta indicaram que os hábitos alimentares desse peixe n o variam ao longo das esta es do ano, refletindo provavelmente a disponibilidade de presas na área de estudo. Esse peixe tem importancia econ mica e a concentra o de THg foi comparada com o limite estabelecido pela Organiza o Mundial de Saúde, demonstrando que os espécimes adultos de T. lepturus est o bem próximos do limite tolerável para uma ingest o regular segura.
Organic matter quality in a soil cultivated with perennial herbaceous legumes
Canellas Luciano Pasqualoto,Espindola José Antonio Azevedo,Rezende Carlos Eduardo,Camargo Plínio Barbosa de
Scientia Agricola , 2004,
Abstract: Using herbaceous legumes in agricultural systems yields great quantities of plant residues, allowing changes in soil organic matter quality and content over the years. This study was conducted on an Ultisol, at Seropédica, RJ, Brazil, to evaluate the effects of different perennial herbaceous legumes on soil organic matter quality. A factorial scheme with three replications was used to evaluate the species: forage groundnut cv. BR-14951 (Arachis pintoi), tropical kudzu (Pueraria phaseoloides), and siratro (Macroptilium atropurpureum). After the first cut, each plot was divided into two subplots; plants were cut and left on the soil surface or cut and removed. Soil samples of a closed area covered by spontaneous vegetation (mainly C3 plants) or by Panicum maximum were also analysed. Samples were collected from two layers (0-5 and 5-10 cm), processed for the fractionation of organic matter and the evaluation of structural characteristics of humic acids (HA). Evaluated legumes did not change total organic carbon contents, but promoted HA accumulation in the superficial soil layer. Humic acids may be used as indicators of the management effects on soil organic fractions, because there was significant incorporation of carbon and nitrogen derived from the legume residues, even for the short experimentation time (28 months). Residue management did not modify quantitative aspects of the distribution of the humified organic matter, but promoted, however, a higher condensation degree of humic acids evaluated by the elementary composition, IR and fluorescence spectroscopy.
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