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| Registros recuperados: 95 | |
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| Lemaitre, Nolwenn; Bayon, Germain; Ondreas, Helene; Caprais, Jean-claude; Freslon, Nicolas; Bollinger, Claire; Rouget, Marie-laure; De Prunele, Alexis; Ruffine, Livio; Olu-le Roy, Karine; Sarthou, Geraldine. |
| Seawater samples were collected by submersible above methane seeps in the Gulf of Guinea (Regab and Baboon pockmarks) in order to investigate the behaviour of iron (Fe), manganese (Mn) and rare earth elements (REE) during fluid seepage. Our aim was to determine whether cold seeps may represent potential sources of dissolved chemical species to the ocean. Dissolved (<0.45 μm filtered samples) and total dissolvable (unfiltered samples) concentrations were determined over ∼50 m long vertical transects above the seafloor and at various discrete locations within the pockmarks. We show that substantial amounts of Fe and Mn are released into seawater during seepage of methane-rich fluids. Mn is exported almost quantitatively in the dissolved form (more than... |
| Tipo: Text |
Palavras-chave: Iron; Rare earth elements; Cold seeps; Seawater; Organic ligands; Iron-sulfide nanoparticles. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00211/32190/30704.pdf |
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| Laes-huon, Agathe; Cathalot, Cecile; Legrand, Julien; Tanguy, Virginie; Sarradin, Pierre-marie. |
| A study of the temporal dynamics of iron concentrations and temperature on a faunal assemblage at the Lucky Strike vent was performed using the Tempo ecological module at the EMSO-Azores deep-sea observatory. The CHEMINI in situ analyzer was implemented on this structure to determine reactive iron concentrations in unfiltered seawater samples along with a temperature probe. Stability tests were performed on the CHEMINI analyzer before deployment (optical module, hyperbaric tests, and deep-sea calibration) for long-term in situ analysis of reactive iron (six months, 2013–2014) at the Tour Eiffel active edifice. Recorded daily, the in situ standard (25 \mu mol.L {}^{-1} ) showed excellent reproducibility (1.07%, n=522 ), confirming satisfactory analytical... |
| Tipo: Text |
Palavras-chave: Deep-sea observatory; Hydrothermal vent; In situ chemical analyzer; Iron; Monitoring the Mid-Atlantic Ridge (MoMAR). |
| Ano: 2016 |
URL: http://archimer.ifremer.fr/doc/00342/45275/46432.pdf |
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| Waeles, Mathieu; Cotte, Laura; Pernet-coudrier, Benoit; Chavagnac, V.; Cathalot, Cecile; Leleu, T.; Laes-huon, Agathe; Perhirin, Antoine; Riso, R. D.; Sarradin, Pierre-marie. |
| Deep-sea hydrothermal venting is now recognized as a major source of iron (Fe), an essential trace element that controls marine productivity. However, the reactions occurring during dispersal from buoyant plumes to neutrally buoyant hydrothermal plumes are still poorly constrained. Here we report for the first time on the dissolved-particulate partition of Fe after in situ filtration at the early stage of mixing at different hydrothermal discharges, i.e., Lucky Strike (37 degrees N), TAG (26 degrees N), and Snakepit (23 degrees N) on the Mid-Atlantic Ridge. We found that hydrothermal iron is almost completely preserved (>90%) in the dissolved fraction, arguing for low iron-bearing sulfide precipitation of iron in basalt-hosted systems with low Fe:H2S... |
| Tipo: Text |
Palavras-chave: Hydrothermal; Iron; Sulfide; Venting; Filtration; Precipitation. |
| Ano: 2017 |
URL: https://archimer.ifremer.fr/doc/00388/49944/50522.pdf |
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| Durand, Jean-pierre; Goudard, Françoise; Pieri, Jacques; Escoubas, Jean-michel; Schreiber, Nathalie; Cadoret, Jean-paul. |
| Ferritin has been shown as being the principal iron storage in the majority of living organisms. In marine species, ferritin is also involved in high-level accumulation of Po-210. As part of our work on the investigation of these radionuclides' concentration in natural environment, ferritin was searched at the gene and protein level. Ferritin was purified from the visceral mass of the oyster Crassostrea gigas by ion-exchange chromatography and HPLC. SDS-PAGE revealed one band of 20 kDa. An Expressed Sequence Tag (EST) library was screened and led to the identification of two complementary DNA (cDNA) involved in ferritin subunit expression. The complete coding sequences and the untranslated regions (UTRs) of the two genes were obtained and a 5' Rapid... |
| Tipo: Text |
Palavras-chave: Iron; IRE; EST; Oyster. |
| Ano: 2004 |
URL: http://archimer.ifremer.fr/doc/2004/publication-693.pdf |
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| Tyrrell, T.; Merico, A.; Waniek, J. J.; Wong, C. S.; Metzl, N.; Whitney, F.. |
| We calculated correlations between seafloor depth and phytoplankton blooms in all three main high-nitrate, low-chlorophyll (HNLC) regions, but with a particular focus on the subarctic North Pacific area. It has long been known that the central parts of the east and west subarctic North Pacific are HNLC regions. The deep western basin of the Bering Sea is also HNLC, whereas the wide continental shelf of the eastern Bering Sea is not. We carried out a statistical comparison of spatial maps of (1) seafloor depth and (2) chlorophyll a concentration from satellite data. This comparison reveals that shallow waters have, on average, higher peak chlorophyll a concentrations (more intense phytoplankton blooms) than deep waters (p << 0.01). Possible artifacts... |
| Tipo: Text |
Palavras-chave: Phytoplankton; Ocean color; Bathymetry; HNLC; North Pacific; Iron. |
| Ano: 2005 |
URL: https://archimer.ifremer.fr/doc/00232/34337/32758.pdf |
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| D´Anna,María Cecilia; Giorgi,Gisela; Roque,Marta Elena. |
| Duodenum, spleen and liver have a crucial role in iron balance on the whole organism and are the major sites of Ferroportin (FPN) expression. Specific regulations between FPN and hepcidin are responsible for changes seen in physiopathological conditions such as inflammation. We studied in vivo effects of turpentine oil-induced acute inflammation on FPN expression, and its relation with prohepcidin and iron mobilization. Immunohistochemical procedures were performed using rabbit anti-mouse FPN and prohepcidin antibodies with goat-labeled polymer-HRP anti-rabbit (DAB) as secondary antibody. Plasma and tissular iron were also studied. Our results showed a notable expression and redistribution of duodenal FPN to basolateral membrane in turpentine-treated mice,... |
| Tipo: Journal article |
Palavras-chave: Iron; Mobilization; Macrophages; Enterocytes. |
| Ano: 2011 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-95022011000300014 |
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| Souza,Carine de F.; Pereira Junior,Waterloo; Garcia,Luciano de O.; Santos,Felipe C. dos; Baldisserotto,Bernardo. |
| ABSTRACT This study analyzed the relationship between several water quality parameters (pH, hardness, alkalinity, turbidity, iron and manganese) levels measured over a 16 year period with fish distribution and aquaculture in the state of Rio Grande do Sul, Southern Brazil. The mean pH values were within a neutral range (6.5-7.5), but the maximum and minimum values reached inappropriate levels for fish farming in some cities. Alkalinity levels were very low (except in the southwest region of the state), which may have contributed to pH variation. Hardness, turbidity, iron (except the region near Caçapava do Sul City) and manganese were within safe ranges for fish farming; however, turbidity levels occasionally increased to levels outside the safe range. In... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Alkalinity; Hardness; Iron; PH; Turbidity. |
| Ano: 2016 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1679-62252016000300205 |
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| Rentería, W.; Ortega, J.. |
| La fertilización de los océanos con hierro han sido presentada como solución a corto plazo para poder reducir CO2 de la atmósfera. Esta afirmación presentada hace 20 años ha liderado y ha despertado un controversial debate sobre las posibles consecuencias en el clima. La bioquímica del hierro es un sistema complejo y su estudio en el océano es relativamente nuevo en comparación con los otros nutrientes, sin embargo, este sistema ha sido descrito en varios estudios que ayudan en la compresión de la afirmación intrincada sobre los beneficios de la fertilización con hierro. El objetivo de este estudio es describir los aspectos relacionados con los fundamentos de la fertilización con hierro, discutiendo acerca de la afirmación de la limitación de hierro y la... |
| Tipo: Journal Contribution |
Palavras-chave: Iron; Pollution effects; Carbon dioxide. |
| Ano: 2012 |
URL: http://hdl.handle.net/1834/4715 |
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| Roekens, E.J.; Van Grieken, R.E.. |
| The rate of iron(II) oxidation in the North Sea water of pH 5.5-10 in the range 10-25°C has been studied. The oxygenation rate depends linearly on the iron(II) and dissolved oxygen concentrations. The second-order dependence on (OH<sup>-</sup>), found by several investigators for synthetic solutions, was confirmed in seawater, but only for pOH>6.9. For pOH<5.9 the rate appeared to be independent of the pOH. In the intermediate range, pOH<5.9-6.9, corresponding to the natural pH of seawater, a first-order dependence on the pOH is obeyed. The important discrepancy in the literature between the second-order rate constant for NaCHO<sub>3</sub> solutions and for seawater can be attributed predominantly to the incorrect... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Iron; Kinetics; Oxidation. |
| Ano: 1983 |
URL: http://www.vliz.be/nl/open-marien-archief?module=ref&refid=3293 |
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| Registros recuperados: 95 | |
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