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| Registros recuperados: 32 | |
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| Tavares,Claudinéia R.O.; Bendassolli,José A.; Coelho,Fernando; Sant'ana Filho,Carlos R.; Prestes,Clelber V.. |
| This work describes a method for 15N-isotope-labeled glycine synthesis, as well as details about a recovery line for nitrogen residues. To that effect, amination of alpha-haloacids was performed, using carboxylic chloroacetic acid and labeled aqueous ammonia (15NH3). Special care was taken to avoid possible 15NH3 losses, since its production cost is high. In that respect, although the purchase cost of the 13N-labeled compound (radioactive) is lower, the stable tracer produced constitutes an important tool for N cycling studies in living organisms, also minimizing labor and environmental hazards, as well as time limitation problems in field studies. The tests were carried out with three replications, and variable 15NH3(aq) volumes in the reaction were used... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Stable isotope; Glycine; Amino acid. |
| Ano: 2006 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0001-37652006000300005 |
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| Won, Eun-ji; Kim, Seung Hee; Go, Young-shin; Kumar, K. Suresh; Kim, Min-seob; Yoon, Suk-hee; Bayon, Germain; Kim, Jung-hyun; Shin, Kyung-hoon. |
| The increasing global consumption of seafood has led to increased trade among nations, accompanied by mislabeling and fraudulent practices that have rendered authentication crucial. The multi-isotope ratio analysis is considered as applicable tool for evaluating geographical authentications but requires information and experience to select target elements such as isotopes, through a distinction method based on differences in habitat and physiology due to origin. The present study examined recombination conditions of multi-elements that facilitated geographically distinct classifications of the clams to sort out appropriate elements. Briefly, linear discriminant analysis (LDA) analysis was performed according to several combinations of five stable isotopes... |
| Tipo: Text |
Palavras-chave: Authentication; Manila clam; Stable isotope; Traceability; Linear discriminant analysis. |
| Ano: 2021 |
URL: https://archimer.ifremer.fr/doc/00685/79701/82488.pdf |
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| Pascal, P.y.; Dupuy, C; Mallet, C; Richard, P; Niquil, N. |
| The fate of benthic bacterial biomass in benthic food webs is a topic of major importance but poorly described. This paper describes an alternative method for evaluation of bacterial grazing rate by meiofauna and macrofauna using bacteria pre-enriched with stable isotopes. Natural bacteria from the sediment of an intertidal mudflat were cultured in a liquid medium enriched with 15NH4Cl. Cultured bacteria contained 2.9% of 15N and were enriched sufficiently to be used as tracers during grazing experiments. Cultured bacteria presented a biovolume (0.21 μm3) and a percentage of actively respiring bacteria (10%) similar to those found in natural communities. The number of Operational Taxon Units found in cultures fluctuated between 56 and 75% of that... |
| Tipo: Text |
Palavras-chave: Tracer; Stable isotope; Sediment; Grazing; Bacteria. |
| Ano: 2008 |
URL: http://archimer.ifremer.fr/doc/2008/publication-4296.pdf |
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| Kopp, Dorothee; Robert, Marianne; Pawlowski, Lionel. |
| In marine ecosystems, the study of trophic relationships has extensively benefited from the development of stable isotope analyses (SIA) as dietary tracers. SIA are particularly useful in elucidating the structure of deep sea food webs given the constraints involved in obtaining gut-content data from deep trawling. We used carbon and nitrogen stable isotope analyses and Stable Isotope Bayesian Ellipses in R (SIBER) and Stable Isotope Analysis in R (SIAR) routines, to determine the trophic ecology of five deep-sea fishes from the upper continental slope of the Celtic Sea. SIA made it possible to deduce some general tendencies in food-web structure and species trophic interactions and confirmed diet determined by gut-content analysis for the same species, in... |
| Tipo: Text |
Palavras-chave: Competition; Feeding habits; Mixing models; Stable isotope. |
| Ano: 2018 |
URL: https://archimer.ifremer.fr/doc/00410/52138/52940.pdf |
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| Oliveira,Fernanda Cristina Caparelli; Silva,Ivo Ribeiro; Ferreira,Gabriel William Dias; Soares,Emanuelle Mercês Barros; Silva,Sérgio Ricardo; Silva,Eulene Francisco. |
| ABSTRACT: Eucalyptus forests in southern Bahia (BA) are planted in soils with a sandy surface layer and humid tropical climate, conditions that lead to soil carbon (C) decomposition. Recent studies have shown that nitrogen (N) may be important for soil C stabilization. The aim of this study was to evaluate the contribution of Eucalyptus harvest residues and nitrogen fertilization to C stabilization in Ultisols of southern BA. The experiment was conducted in Eucalyptus clonal plantations cultivated in two regions of Eunápolis, BA, Brazil, with different clay content: southern region (140 g kg-1 of clay) and western region (310 g kg-1 of clay). Five treatments were evaluated: one control (CTR), without Eucalyptus harvest residues and N fertilization, and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Planted forests; Harvest residue management; Soil organic matter; Stable isotope. |
| Ano: 2018 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832018000100501 |
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| Manetta, Gislaine Iachstel; UEM; Benedito, Evanilde; UEM, Maringá; Ducatti, Carlos; UNESP. |
| The present study investigates the δ13C and δ15N isotopic composition in frozen samples (control), samples in alcohol and in formaldehyde of Plagioscion squamosissimus and Hypophthalmus edentates. From each individual we extracted a strip of muscle from the region above the lateral line, in the dorsal fin base, that was divided into three equal parts, each one was submitted to one type of treatment: freeze – control group (-15oC), conservation in alcohol 70% and fixation in formaldehyde 4%. Samples were kept under those treatments for 30 days, washed and submerged in distilled water for 4 hours. Afterwards, they were dried up in air oven at 60oC for 48 hours and macerated until the obtaining of a fine powder. A significant difference... |
| Tipo: Composição isotópica |
Palavras-chave: Stable isotope; Preservative; Fishes; Plagioscion squamosissimus; Hypophthalmus edentatus 2.05.00.00-9 Ecologia stable isotope; Preservative; Fishes; Plagioscion squamosissimus; Hypophthalmus edentatus. |
| Ano: 2011 |
URL: http://periodicos.uem.br/ojs/index.php/ActaSciBiolSci/article/view/7045 |
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| Pasquaud, Stéphanie; Lobry, Jeremy; Elie, Pierre. |
| Estuarine areas are sites of human pressures and degradation. In order to maintain and/or restore the quality of estuarine ecosystems, it is necessary to describe their structure and functioning. For that reason, many recent scientific works focus on food webs, which are depicted as being good indicators of the functioning of aquatic ecosystems. Hence it is necessary to question how estuarine food webs can be described. This paper proposes a pragmatic and practical review of the most widely used techniques (stomach/gut content analysis, stable isotope ratios and biochemical markers) with emphasis on their main advantages, drawbacks and bias according to possible ecological goals (ecological quality objectives). These approaches, although quite different,... |
| Tipo: Text |
Palavras-chave: Trophic model; Biochemical marker; Stable isotope; Stomach/gut content analysis; Estuarine food web. |
| Ano: 2007 |
URL: http://archimer.ifremer.fr/doc/2007/publication-2784.pdf |
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| Fenilli,Tatiele Anete Bergamo; Reichardt,Klaus; Dourado-Neto,Durval; Trivelin,Paulo César Ocheuze; Favarin,José Laercio; Costa,Flávio Murilo Pereira da; Bacchi,Osny Oliveira Santos. |
| The relationship between growth and fertilizer nitrogen recovery by perenial crops such as coffee is poorly understood and improved understanding of such relations is important for the establishment of rational crop management practices. In order to characterize the growth of a typical coffee crop in Brazil and quantify the recovery of 15N labeled ammonium sulfate, and improve information for fertilizer management practices this study presents results for two consecutive cropping years, fertilized with 280 and 350 kg ha-1 of N, respectively, applied in four splittings, using five replicates. Shoot dry matter accumulation was evaluated every 60 days, separating plants into branches, leaves and fruits. Labeled sub-plots were used to evaluate N-total and 15N... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Coffea arabica L.; Stable isotope; Nitrogen; Dry matter accumulation; 15N. |
| Ano: 2007 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162007000500012 |
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| Pascal, Pierre-yves; Dubois, Stanislas; Goffette, Anais; Lepoint, Gilles. |
| The activity of the geothermal plant at Bouillante in Guadeloupe (French West Indies) releases thioautotrophic bacteria into the coastal environment. Fish counts reveal that fish abundance increases with higher availability of this bacterial resource. In order to evaluate the trophic role of these bacteria, isotopic compositions (C, N, S) of potential consumers were evaluated on transects at increasing distance from the source of bacteria. The 3 mobile fish species examined (Abudefduf saxatilis, Acanthurus bahianus, and Stegastes partitus) ingested and assimilated chemosynthetic bacteria. Similarly, the isotopic composition of the mobile sea urchin Diadema antillarum was different close to the discharge channel, suggesting a diet mainly composed of sulfur... |
| Tipo: Text |
Palavras-chave: Shallow vent; Food web; Sulfur bacteria; Stable isotope. |
| Ano: 2017 |
URL: http://archimer.ifremer.fr/doc/00404/51511/52256.pdf |
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| Rossete,Alexssandra Luiza Rodrigues Molina; Carneiro,Josiane Meire Toloti; Sant Ana Filho,Carlos Roberto; Bendassolli,José Albertino. |
| Sulphur plays an essential role in plants and is one of the main nutrients in several metabolic processes. It has four stable isotopes (32S, 33S, 34S, and 36S) with a natural abundance of 95.00, 0.76, 4.22, and 0.014 in atom %, respectively. A method for isotopic determination of S by isotope-ratio mass spectrometry (IRMS) in soil samples is proposed. The procedure involves the oxidation of organic S to sulphate (S-SO4(2-)), which was determined by dry combustion with alkaline oxidizing agents. The total S-SO4(2-) concentration was determined by turbidimetry and the results showed that the conversion process was adequate. To produce gaseous SO2 gas, BaSO4 was thermally decomposed in a vacuum system at 900 ºC in the presence of NaPO3. The isotope... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Sample preparation; Soil samples; Isotopic dilution; Labeled material; Stable isotope; 34S. |
| Ano: 2012 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832012000600012 |
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| Marques,Thiago S.; Tassoni-Filho,Maurício; Ferronato,Bruno O.; Guardia,Isabela; Verdade,Luciano M.; Camargo,Plínio B. de. |
| 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... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Diet; Freshwater turtles; Geoffroy's side-necked-turtle; Metabolic processes; Stable isotope. |
| Ano: 2011 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1984-46702011000300016 |
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| Andersson, C; Risebrobakken, B; Jansen, E; Dahl, So. |
| Late Holocene sea surface ocean conditions of the eastern Norwegian Sea (Voring Plateau) are inferred from planktic stable isotopes and planktic foraminiferal assemblage changes in cores JM97-948/2A and MD95-2011 (66.97degreesN, 7.64degreesE). Strong covariance between the planktic stable oxygen isotopic record and abundance changes of N. pachyderma (sin) show that major changes in surface ocean conditions are reflected both in the geochemical composition of the foraminiferal tests as well as in the composition of the foraminiferal fauna. Surface ocean conditions warmer than present were common during the past 3000 years. During the so-called Medieval Warm Period, surface conditions were highly variable with marked changes in sea surface temperature. The... |
| Tipo: Text |
Palavras-chave: Paleoceanography; Stable isotope; Holocene; Micropaleontology. |
| Ano: 2003 |
URL: https://archimer.ifremer.fr/doc/00224/33495/31954.pdf |
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| Pond, David W; Segonzac, Michel; Bell, Michael V; Dixon, David R; Fallick, Anthony E; Sargent, John R. |
| Mirocaris fortunata were sampled from the Lucky Strike hydrothermal vent area (Eiffel Tower site) on the mid-Atlantic ridge during the French DIVA 2 cruise (June 1994). Small adults (17 to 22 mm total length), although morphologically identical, could be divided into 2 categories on the basis of pigmentation, lipid composition and C-13/C-12 stable isotope ratios of fatty acids. Highly pigmented small adults (8.6 to 9.2 mu g carotenoid shrimp(-1)) contained higher levels of total lipid than similar-sized individuals containing lower levels of pigment (0.9 to 2.9 mu g carotenoid shrimp(-1)). Lipid class analysis indicated that wax esters comprised 62.5% of total lipid in the former group. These pigmented shrimp also contained high proportions of... |
| Tipo: Text |
Palavras-chave: Mirocaris fortunata; Lipid; Stable isotope; Hedge betting. |
| Ano: 1997 |
URL: http://archimer.ifremer.fr/doc/00337/44783/44491.pdf |
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| Hachikubo, Akihiro; Yanagawa, Katsunori; Tomaru, Hitoshi; Lu, Hailong; Matsumoto, Ryo. |
| Hydrate-bearing sediment cores were retrieved from the Joetsu Basin (off Joetsu city, Niigata Prefecture) at the eastern margin of the Japan Sea during the MD179 gas hydrates cruise onboard R/V Marion Dufresne in June 2010. We measured molecular and stable isotope compositions of volatiles bound in the gas hydrates and headspace gases obtained from sediments to clarify how the minor components of hydrocarbons affects to gas hydrate crystals. The hydrate-bound hydrocarbons at Umitaka Spur (southwestern Joetsu Basin) primarily consisted of thermogenic methane, whereas those at Joetsu Knoll (northwestern Joetsu Basin, about 15 km from Umitaka Spur) contained both thermogenic methane and a mixture of thermogenic and microbial methane. The depth concentration... |
| Tipo: Text |
Palavras-chave: Gas hydrate; Japan Sea; Stable isotope; Neopentane; Biodegradation. |
| Ano: 2015 |
URL: https://archimer.ifremer.fr/doc/00294/40493/39284.pdf |
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| Marchini,J.S.; Lambertini,C.R.; Ferriolli,E.; Dutra de Oliveira,J.E.. |
| This study examined if leucine, arginine or glycine supplementation in adult obese patients (body mass index of 33 ± 4 kg/m²) consuming a Brazilian low energy and protein diet (4.2 MJ/day and 0.6 g protein/kg) affects protein and amino acid metabolism. After four weeks adaptation to this diet, each subject received supplements of these amino acids (equivalent to 0.2 g protein kg-1 day-1) in random order. On the seventh day of each amino acid supplementation, a single-dose 15N-glycine study was carried out. There were no significant differences in protein flux, synthesis or breakdown. The protein flux (grams of nitrogen, gN/9 h) was 55 ± 24 during the nonsupplemented diet intake and 39 ± 10, 44 ± 22 and 58 ± 35 during the leucine-, glycine- and... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Obese women; Protein; Glycine; Arginine; Leucine; Stable isotope. |
| Ano: 2001 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-879X2001001000007 |
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| Registros recuperados: 32 | |
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