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Registros recuperados: 78 | |
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Duperron, Sebastien; Gaudron, Sylvie M.; Lemaitre, Nolwenn; Bayon, Germain. |
Tubeworms within the annelid family Siboglinidae rely on sulfur-oxidizing autotrophic bacterial symbionts for their nutrition, and are among the dominant metazoans occurring at deep-sea hydrocarbon seeps. Contrary to their relatives from hydrothermal vents, sulfide uptake for symbionts occurs within the anoxic subsurface sediment, in the posterior ‘root’ region of the animal. This study reports on an integrated microbiological and geochemical investigation of the cold seep tubeworm Escarpia southwardae collected at the Regab pockmark (Gulf of Guinea). Our aim was to further constrain the links between the animal and its symbiotic bacteria, and their environment. We show that E. southwardae harbors abundant sulfur-oxidizing bacterial symbionts in its... |
Tipo: Text |
Palavras-chave: Sulfur-oxidizing bacteria; RTCA; Trace elements; RubisCO; Symbiosis. |
Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00191/30251/28683.pdf |
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Satow, C.; Tomlinson, E. L.; Grant, K. M.; Albert, P. G.; Smith, V. C.; Manning, C. J.; Ottolini, L.; Wulf, S.; Rohling, E. J.; Lowe, J. J.; Blockley, S. P. E.; Menzies, M. A.. |
Tephra layers preserved in marine sediments can contribute to the reconstruction of volcanic histories and potentially act as stratigraphic isochrons to link together environmental records. Recent developments in the detection of volcanic ash (tephra) at levels where none is macroscopically visible (so-called ‘crypto-tephra’) have greatly enhanced the potential of tephrostratigraphy for synchronising environmental and archaeological records by expanding the areas over which tephras are found. In this paper, crypto-tephra extraction techniques allow the recovery of 8 non-visible tephra layers to add to the 9 visible layers in a marine sediment core (LC21) from the SE Aegean Sea to form the longest, single core record of volcanic activity in the Aegean Sea.... |
Tipo: Text |
Palavras-chave: Tephra; Trace elements; Santorini; Campanian Ignimbrite; Pantelleria; Kos; Yali; Aegean sea; Mediterranean. |
Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00294/40498/39433.pdf |
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Bahr, Andre; Lamy, Frank; Arz, Helge W.; Major, Candace; Kwiecien, Olga; Wefer, Gerold. |
[1] New Mg/Ca, Sr/Ca, and published stable oxygen isotope and Sr-87/(86) Sr data obtained on ostracods from gravity cores located on the northwestern Black Sea slope were used to infer changes in the Black Sea hydrology and water chemistry for the period between 30 to 8 ka B. P. ( calibrated radiocarbon years). The period prior to 16.5 ka B. P. was characterized by stable conditions in all records until a distinct drop in delta O-18 values combined with a sharp increase in Sr-87/(86) Sr occurred between 16.5 and 14.8 ka B. P. This event is attributed to an increased runoff from the northern drainage area of the Black Sea between Heinrich Event 1 and the onset of the Bolling warm period. While the Mg/Ca and Sr/Ca records remained rather unaffected by this... |
Tipo: Text |
Palavras-chave: Black Sea; Ostracods; Trace elements. |
Ano: 2008 |
URL: https://archimer.ifremer.fr/doc/00209/31989/30432.pdf |
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Metian, M.; Bustamante, Paco; Hedouin, L.; Warnau, M.. |
Uptake of waterborne Cd, Co, Mn and Zn was determined in laboratory experiments using radiotracer techniques (Cd-109, Co-57, Mn-54 and Zn-65). Labelled Zn was mainly accumulated in the digestive gland (65%) and Co in kidneys (81%); Cd and Mn were similarly distributed in digestive gland and gills. In a complementary field study, Ag, As, Cd, Co, Cr, Cu, Fe, Mn, Ni, and Zn were analysed in scallops collected at two stations showing different contamination levels. Digestive gland and kidneys displayed the highest concentrations. Ag, As, Cd, and Fe differed in soft tissues from the two stations, suggesting that Comptopallium radula could be a valuable local biomonitor species for these elements. Low Mn and Zn concentrations found in kidneys suggest that their... |
Tipo: Text |
Palavras-chave: Bioindicator species; Risk assessment; Pectinidae; Radiotracers; Arsenic; Trace elements; Tropical environment. |
Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-6953.pdf |
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Flament, P; Lepretre, A; Noel, S; Auger, Y. |
Dix-huit prélèvements d'aérosols ont été effectués en Manche Nord, soit en bordure de mer, soit à quelques milles au large, à l'aide d'un impacteur à cascade (5 étages). L'ensemble des données (concentrations de 8 éléments répartis en 6 classes granulométriques successives) est exploité par analyse factorielle des correspondances. Celle-ci permet de mettre en évidence de larges déformations dans les spectres granulométriques pour les éléments traceurs marin et terrestre (Na et Al). En opposition, les métaux résultant d'activité anthropique (Fe, Pb, Zn, Mn), ont des comportements beaucoup plus typés. Parmi ceux-ci, la présence du manganèse sur le site paraît être indépendante de celle des autres métaux et imputable à une seule source. Pb, Fe, Zn et cuivre... |
Tipo: Text |
Palavras-chave: Aérosols; Éléments-traces; Analyse par correspondance; Distribution granulométrique; Littoral; Aerosols; Trace elements; Correspondence analysis; Size distribution; Coastal. |
Ano: 1987 |
URL: http://archimer.ifremer.fr/doc/00110/22082/19723.pdf |
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Silva,Rita de Cássia Ferreira da; Silva,Fernando Bruno Vieira da; Biondi,Caroline Miranda; Nascimento,Clístenes Williams Araújo do; Oliveira,Emídio Cantídio Almeida de. |
ABSTRACT Micronutrient research for sugarcane in northeastern Brazil is scarce and most works on this issue date back to the 70’s and 80’s. The objectives of this study were to assess the available and reserve pools of Fe, Mn, Cu, and Zn in soils cultivated with sugarcane under three geological contexts in northeastern Brazil as well as to diagnose the micronutrient nutritional status of sugarcane grown on these areas in order to identify pedogeological conditions in which micronutrient deficiencies are likely. Results showed that the soils cultivated with sugarcane in the states of Paraíba and Pernambuco posed available and reserve contents of micronutrients related to the parent materials and soil textural classes. The reserve contents of Fe, Mn, Zn, and... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil fertility; Trace elements; Plant nutrition; Critical levels. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832019000100522 |
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Pugliese,Camila; Patin,Rose Vega; Palchetti,Cecilia Zanin; Claudio,Cristiane Chiantelli; Gouvêa,Aída de Fátima Thomé Barbosa; Succi,Regina Célia de Menezes; Amancio,Olga Maria Silverio; Cozzolino,Silvia Maria Franciscato; Oliveira,Fernanda Luisa Ceragioli. |
Objective:This study aims to assess the nutritional status of selenium, copper and zinc; and also the erythrocyte superoxide dismutase activity of HIV-infected children compared to a control group.Methods:A cross-sectional study was carried out with prepubertal HIV-infected children (n = 51) and their healthy siblings (n = 32). All biochemical measurements including plasma selenium, serum copper levels, serum and erythrocyte zinc levels and erythrocyte super-oxide dismutase activity were evaluated according to dietary, clinical and biochemical parameters.Results:Compared to the control group, the HIV-infected children had lower z-score values for height-for-age (p = 0.0006), higher prevalence of stunting (11.8%) (p = 0.047), lower selenium levels (p =... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Antioxidants; HIV and nutrition; Oxidative stress; Trace elements. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1413-86702014000500481 |
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Alkmim Filho,J. F.; Germano,A.; Dibai,W.L.S.; Vargas,E.A.; Melo,M.M.. |
The aim of this study was to investigate the presence of arsenic, lead and cadmium residues in samples of liver, kidney and muscle of poultry and swine during the years from 2002 to 2008. A total of 1978 samples were analyzed: 1031 of poultry and 947 of swine from Brazilian slaughterhouses. The samples were analyzed at the National Agricultural Laboratory using the atomic absorption spectrometry technique. In poultry, the arsenic residues were detected in 53.6% of liver samples, although no results have exceeded the MRL. In kidneys, 39.7% of the samples showed measurable residues and there was no violation of the limits. Regarding lead, there were 5 contaminated liver samples and 24 contaminated kidney samples (1.5 and 3.6% respectively). In muscle tissue... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Trace elements; Arsenic; Cadmium; Lead. |
Ano: 2014 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0102-09352014000200022 |
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Almeida Júnior,Agenor Bezerra de; Nascimento,Clístenes Williams Araújo do; Biondi,Caroline Miranda; Souza,Adailson Pereira de; Barros,Felipe Martins do Rêgo. |
ABSTRACT Soil contamination by heavy metals threatens ecosystems and human health. Environmental monitoring bodies need reference values for these contaminants to assess the impacts of anthropogenic activities on soil contamination. Quality reference values (QRVs) reflect the natural concentrations of heavy metals in soils without anthropic interference and must be regionally established. The aim of this study was to determine the natural concentrations and quality reference values for the metals Ag, Ba, Cd, Co, Cu, Cr, Mo, Ni, Pb, Sb and Zn in soils of Paraíba state, Brazil. Soil samples were collected from 94 locations across the state in areas of native vegetation or with minimal anthropic interference. The quality reference values (QRVs) were (mg... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Geochemistry; Soil pollution; Micronutrients; Trace elements. |
Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832016000100509 |
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Zelaya,Katherin Prissila Sevilla; Alves,Barbara Samartini Queiroz; Colen,Fernando; Frazão,Leidivan Almeida; Sampaio,Regynaldo Arruda; Pegoraro,Rodinei Facco; Fernandes,Luiz Arnaldo. |
ABSTRACT: The biomass pyrolysis process may be an alternative for the agricultural use of sewage sludge. This study aimed to evaluate the use of of biochars from mixture of sewage sludge and sugarcane bagasse (BB, 1:1 relationship sewage sludge and sugarcane bagasse) on sugar beet (Beta vulgaris L.) production and nutrition. A greenhouse experiment was conducted with five application rates of BB: 0, 2.5, 5, 7.5, and 10% (v/v), and two additional treatments, biochar from sewage sludge (BS, application rate 5% (v/v)) and conventional treatment (CV) that received lime and mineral fertilizer. The treated soils were incubated for 45 days, after which, seedlings were cultivated for 55 days. Biochar produce from sewage sludge and sugarcane bagasse is an... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Beta vulgaris L.; Trace elements; Pyrolysis; Fine roots.. |
Ano: 2019 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782019000500202 |
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Oliveira,Mara Lucia Jacinto; Araujo,Ademir Sérgio Ferreira de; Melo,Wanderley José de. |
Tannery sludge contains high concentrations of inorganic elements, such as chromium (Cr), which may lead to environmental pollution and affect human health The behavior of Cr in organic matter fractions and in the growth of cowpea (Vigna unguiculata L.) was studied in a sandy soil after four consecutive annual applications of composted tannery sludge (CTS). Over a four-year period, CTS was applied on permanent plots (2 × 5 m) and incorporated in the soil (0-20 cm) at the rates of 0, 2.5, 5.0, 10.0, and 20.0 Mg ha-1 (dry weight basis). These treatments were replicated four times in a randomized block design. In the fourth year, cowpea was planted and grown for 50 days, at which time we analyzed the Cr concentrations in the soil, in the fulvic acid, humic... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Soil contamination; Humic substances; Solid residue; Heavy metals; Plant growth; Trace elements. |
Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832015000100297 |
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Brunetto,Gustavo; Benedet,Lucas; Ambrosini,Vítor Gabriel; Comin,Jucinei Jose; Melo,George Wellington Bastos de; Santos,Matheus Ademir dos; Lourenzi,Cledimar Rogério; Loss,Arcangelo; Belli Filho,Paulo; Schmitt,Djalma Eugênio; Couto,Rafael. |
ABSTRACT The present study aimed to evaluate the accumulation and distribution of Cu and Zn fractions in the profile of an Inceptisol by application of fungicides with a previous history of apple cultivation in southern Brazil. Stratified soil samples (0.0 – 0.025 m, 0.025 –0.050 m, 0.05 – 0.10 m, 0.10 – 0.15 m, 0.15 – 0.20 m and 0.20 – 0.40 m depth) were collected in two apple orchards (8 years old and 18 years old), and in a native pasture area adjacent to the orchards. The soil was subjected to analysis of physical and chemical properties and to chemical fractionation of Cu and Zn. The fractions of soluble, exchangeable, organic, residual and total Cu and Zn accumulated in the topsoil (0.0 – 0.025 m) of the orchards, being higher in the orchard... |
Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Malus domestica; Trace elements; Toxicity; Environmental contamination. |
Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0006-87052018000200333 |
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Freslon, Nicolas; Bayon, Germain; Birot, Dominique; Bollinger, Claire; Barrat, Jean-alix. |
This paper reports on a novel procedure for determining trace element abundances (REE and Y, Cr, Mn, Co) in seawater by inductively coupled plasma sector field mass spectrometry (ICP-SFMS). The procedure uses a combination of pre-concentration using co-precipitation onto magnesium hydroxides and addition of thulium spike. The validity of the method was assessed onto 25 ml volumes of certified reference materials (NASS- and CASS-4) and in house seawater standard. Procedural blanks were determined by applying the same procedure to aliquots of seawater previously depleted in trace elements by successive Mg(OH)(2) co-precipitations, yielding estimated contributions to the studied samples better than 1.1% for all elements, with the exception of Cr (<3.3%)... |
Tipo: Text |
Palavras-chave: Trace elements; Rare earth elements (REE); Seawater; Mg(OH)(2) co-precipitation; ICP-MS; Thulium. |
Ano: 2011 |
URL: http://archimer.ifremer.fr/doc/00041/15220/15855.pdf |
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Registros recuperados: 78 | |
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