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| Registros recuperados: 78 | |
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| Gamundí,Irma J.; Minter,David W.; Romero,Andrea I.; Barrera,Viviana A.; Giaiotti,Andreina L.; Messuti,María I.; Stecconi,Marina. |
| Information about fungi of the orders Cyttariales, Helotiales, Ostropales, Pezizales, Rhytismatales and Thelebolales (Discomycetes) collected in Patagonia, Tierra del Fuego and adjacent antarctic areas (Patagonia), and information about their associated organisms was located, abstracted, keyboarded, edited and validated. The largest single information sources were dried reference collections in Argentina and elsewhere, and published information as listed in this work's bibliography. Other records were derived from fresh collections, other reference collections and field observations. Information is stored in a computerized system of relational databases for taxonomic, nomenclatural, bibliographic and biological observations data. This system allows storage... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Discomycetes; Patagonia; Tierra del Fuego; Antarctica; Checklist. |
| Ano: 2004 |
URL: http://www.scielo.org.ar/scielo.php?script=sci_arttext&pid=S0011-67932004000100006 |
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| Asencio,Geraldine; Lavin,Paris; Alegría,Karen; Domínguez,Mariana; Bello,Helia; González-Rocha,Gerardo; González-Aravena,Marcelo. |
| Background The increment of resistant strains to commonly used antibiotics in clinical practices places in evidence the urgent need to search for new compounds with antibacterial activity. The adaptations that Antarctic microorganisms have developed, due to the extreme environment that they inhabit, promote them as a potential new source of active compounds for the control of microorganisms causing infections associated with health care. The aim of this study was to evaluate the antibacterial activity of an ethanol extract of the Antarctic bacterium Janthinobacterium sp., strain SMN 33.6, against nosocomial multi-resistant Gram-negative bacteria. Results Inhibitory activity against human Gram-negative bacterial pathogens, with concentrations that varied... |
| Tipo: Journal article |
Palavras-chave: Antarctica; Antimicrobial; Antibiotic resistance; Bacterial pigment. |
| Ano: 2014 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582014000100001 |
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| Gutt,Julian; Arntz,Wolf E; Balguerias,Eduardo; Brandt,Angelika; Gerdes,Dieter; Gorny,Matthias; Sirenko,Boris. |
| A look at the latitudinal gradient from North America via South America to Antarctica supports the impression that the ecosystems of this part of the world provide perfect conditions for marine biodiversity studies. Several bilateral or international initiatives with major German contributions have focused on biodiversity questions, especially in South America and Antarctica. At depths > 50 m accessible to shipboard sampling, an oxygen minimum zone (OMZ) prevails off Peru and Chile (except in the extreme south). The macrobenthic biota associated with the OMZ are extremely poor but show a gradient of increasing diversity at great depths and towards the south. In the southern Chilean fjords and channels, habitat heterogeneity is high and differences in... |
| Tipo: Journal article |
Palavras-chave: Marine biodiversity; South America; Antarctica. |
| Ano: 2003 |
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-65382003000200007 |
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| Giuliani, S.; Triulz, C.; Vaghi, M.. |
| In the framework of the Italian National Research Program in Antarctica (PNRA), the Laboratory of Radioecology of the University of Parma developed from 1987 several researches on terrestrial and marine samples. At first the prin-cipal aim was the study of 90Sr, 137Cs, 238Pu, 239+240Pu and 241Am concentrations in samples of soil, ice, seawater and biota collected near the Italian Antarctic Base (Ross Sea, Terra Nova Bay). |
| Tipo: Journal Contribution |
Palavras-chave: Antarctica; Pollution; 137Cs; 239+240Pu; 238Pu and 241Am; Антарктика; Загрязнение Pollution Pollution http://aims.fao.org/aos/agrovoc/c_6077. |
| Ano: 2003 |
URL: http://repository.ibss.org.ua/dspace/handle/99011/39 |
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| Burdman,Luciana; Daneri,Gustavo A.; Negrete,Javier; Mennucci,Jorge A.; Marquez,Maria E. I.. |
| The aim of the present study was to enhance the knowledge of the feeding habits of the juvenile component of the population of Southern elephant seals [Mirounga leonina (Linnaeus, 1758)] from Isla 25 de Mayo, South Shetland Islands, age class whose diet information is scarce. A total of 60 individuals were stomach lavaged in the spring - summer seasons of three consecutive years (2003, 2004 and 2005) of which 53.3 % (n = 32) presented food remnants. The Antarctic glacial squid Psychroteuthis glacialis Thiele, 1921 was the dominant prey taxon in terms of frequency of occurrence (68.7%), numerical abundance (60.1%) and biomass (51.5%), contributing 84.1% to the total relative importance index. Other squid prey species of importance were Slosarczykovia... |
| Tipo: Info:eu-repo/semantics/article |
Palavras-chave: Mirounga; Diet; Antarctica. |
| Ano: 2015 |
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0073-47212015000100012 |
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| Brown, Mark V.; Lauro, Federico M.; Demaere, Matthew Z.; Muir, Les; Wilkins, David; Thomas, Torsten; Riddle, Martin J.; Fuhrman, Jed A.; Andrews-pfannkoch, Cynthia; Hoffman, Jeffrey M.; Mcquaid, Jeffrey B.; Allen, Andrew; Rintoul, Stephen R.; Cavicchioli, Ricardo. |
| The ubiquitous SAR11 bacterial clade is the most abundant type of organism in the world’s oceans, but the reasons for its success are not fully elucidated. We analysed 128 surface marine metagenomes, including 37 new Antarctic metagenomes. The large size of the data set enabled internal transcribed spacer (ITS) regions to be obtained from the Southern polar region, enabling the first global characterization of the distribution of SAR11, from waters spanning temperatures −2 to 30°C. Our data show a stable co-occurrence of phylotypes within both ‘tropical’ (>20°C) and ‘polar’ (<10°C) biomes, highlighting ecological niche differentiation between major SAR11 subgroups. All phylotypes display transitions in abundance that are strongly correlated with... |
| Tipo: Text |
Palavras-chave: Adaptive radiation; Antarctica; Metagenome; Pelagibacter; Phylotype distribution. |
| Ano: 2012 |
URL: https://archimer.ifremer.fr/doc/00140/25132/23242.pdf |
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| Gonzalez-aravena, Marcelo; Perez-troncoso, Carolina; Urtubia, Rocio; Branco, Paola; Machado Cunha Da Silva, Jose Roberto; Mercado, Luis; De Lorgeril, Julien; Bethke, Jorn; Paschke, Kurt. |
| In the Antarctic marine environment, the water temperature is usually between 2 and - 1.9 degrees C. Consequently, some Antarctic species have lost the capacity to adapt to sudden changes in temperature. The study of the immune response in Antarctic sea urchin (Sterechinus neumayeri) could help us understand the future impacts of global warming on endemic animals in the Antarctic Peninsula. In this study, the Antarctic sea urchins were challenged with lipopolysaccharides and Vibrio alginolitycus. The cellular response was evaluated by the number of coelomocytes and phagocytosis. A significant increase was observed in red sphere cells and total coelomocytes in animals exposed to LPS. A significant rise in phagocytosis in animals stimulated by LPS was also... |
| Tipo: Text |
Palavras-chave: Sea urchin; Antarctica; Sterechinus neumayeri; Coelomocytes; Phagocytosis; Gene expression. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00439/55012/56441.pdf |
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| Preunkert, Susanne; Legrand, Michel; Jourdain, Bruno; Moulin, Cyril; Belviso, Sauveur; Kasamatsu, Nobue; Fukuchi, Mitsuo; Hirawake, Toru. |
| A multiple year-round study of atmospheric dimethyl sulfide (DMS) (from December 1998 to April 2003) as well as sulfur-derived aerosols (methanesulfonic acid (MSA) and non-sea-salt sulfate) (from March 1991 to February 2003) was conducted at Dumont d'Urville, coastal Antarctica. The three sulfur-derived species exhibit a seasonal cycle characterized by maxima in midsummer (January). Whereas the interannual variability of winter levels remains low, a strong interannual variability is shown in summer, particularly for DMS and MSA, and to a lesser extent for non-sea-salt sulfate. Over the 1998-2003 time period, January 2002 stands out with high values for all sulfur species. These interannual variabilities of atmospheric summer levels are examined in the... |
| Tipo: Text |
Palavras-chave: Sulfur cycle; Antarctica; Dimethylsulfure. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00236/34728/33177.pdf |
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| Crosta, X.; Debret, M.; Denis, D.; Courty, M. A.; Ther, O.. |
| Diatom data from a marine sediment core give insight on Holocene changes in sea- surface conditions and climate at high southern latitudes off Adelie Land, East Antarctica. The early to mid- Holocene was warmer than the late Holocene with a transition at similar to 4000 calendar years B. P. Sea ice was less present and spring- summer growing season was greater during the warm period relative to the cold one, thus limiting sea ice diatom production and favoring more open ocean diatom to develop. The long- term Holocene climatic evolution in East Antarctica is explained by a combination of a delayed response to local seasonal insolation changes coupled to the long memory of the Southern Ocean. Abrupt variations of the diatom relative abundances, indicating... |
| Tipo: Text |
Palavras-chave: Antarctica; Sea ice; Holocene; Insolation; Thermohaline circulation. |
| Ano: 2007 |
URL: https://archimer.ifremer.fr/doc/00235/34642/33044.pdf |
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| Tournadre, Jean; Bouhier, Nicolas; Girard-ardhuin, Fanny; Remy, F.. |
| Large uncertainties exist on the volume of ice transported by the Southern Ocean large icebergs, a key parameter for climate studies, because of the paucity of information, especially on iceberg thickness. Using icebergs tracks from the National Ice Center (NIC) and Brigham Young University (BYU) databases to select altimeter data over icebergs and a method of analysis of altimeter waveforms, a database of 5366 icebergs freeboard elevation, length, and backscatter covering the 2002–2012 period has been created. The database is analyzed in terms of distributions of freeboard, length, and backscatter showing differences as a function of the iceberg's quadrant of origin. The database allows to analyze the temporal evolution of icebergs and to estimate a melt... |
| Tipo: Text |
Palavras-chave: Iceberg; Antarctica; Altimetry; Ice balance. |
| Ano: 2015 |
URL: http://archimer.ifremer.fr/doc/00256/36719/35333.pdf |
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| Nichols, Carol; Bowman, John; Guezennec, Jean. |
| The sea ice microbial community plays a key role in the productivity of the Southern Ocean. Exopolysaccharide (EPS) is a major component of the exopolymer secreted by many marine bacteria to enhance survival and is abundant in sea ice brine channels, but little is known about its function there. This study investigated the effects of temperature on EPS production in batch culture by CAM025, a marine bacterium isolated from sea ice sampled from the Southern Ocean. Previous studies have shown that CAM025 is a member of the genus Pseudoalteromonas and therefore belongs to a group found to be abundant in sea ice by culture-dependent and -independent techniques. Batch cultures were grown at -2 degrees C, 10 degrees C, and 20 degrees C, and cell number, optical... |
| Tipo: Text |
Palavras-chave: EPS yield; Psychrotolerant; Sea ice; Marine bacteria; Antarctica; Exopolymer; Exopolysaccharides. |
| Ano: 2005 |
URL: http://archimer.ifremer.fr/doc/2005/publication-625.pdf |
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| Matsumoto, Haru; Bohnenstiehl, Delwayne R.; Tournadre, Jean; Dziak, Robert P.; Haxel, Joseph H.; Lau, T. -k. A.; Fowler, Matt; Salo, Sigrid A.. |
| In late 2007, two massive icebergs, C19a and B15a, drifted into open water and slowly disintegrated in the southernmost Pacific Ocean. Archived acoustic records show that the high-intensity underwater sounds accompanying this breakup increased ocean noise levels at mid-to-equatorial latitudes over a period of ∼1.5 years. More typically, seasonal variations in ocean noise, which are characterized by austral summer-highs and winter-lows, appear to be modulated by the annual cycle of Antarctic iceberg drift and subsequent disintegration. This seasonal pattern is observed in all three Oceans of the Southern Hemisphere. The life cycle of Antarctic icebergs affects not only marine ecosystem but also the sound environment in far-reaching areas and must be... |
| Tipo: Text |
Palavras-chave: Antarctica; Iceberg; Ocean noise; Seasonality; Trend. |
| Ano: 2014 |
URL: http://archimer.ifremer.fr/doc/00205/31613/30035.pdf |
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| Convey, P.; Bindschadler, R.; Di Prisco, G.; Fahrbach, E.; Gutt, J.; Hodgson, D. A.; Mayewski, P. A.; Summerhayes, C. P.; Turner, J.; ACCE CONSORTIUM. |
| The Antarctic climate system varies on timescales from orbital, through millennial to sub-annual, and is closely coupled to other parts of the global climate system. We review these variations from the perspective of the geological and glaciological records and the recent historical period from which we have instrumental data (similar to the last 50 years). We consider their consequences for the biosphere, and show how the latest numerical models project changes into the future, taking into account human actions in the form of the release of greenhouse gases and chlorofluorocarbons into the atmosphere. In doing so, we provide an essential Southern Hemisphere companion to the Arctic Climate Impact Assessment. |
| Tipo: Text |
Palavras-chave: Antarctica; Biology; Environmental change; Geology; Glaciology; Southern Ocean. |
| Ano: 2009 |
URL: https://archimer.ifremer.fr/doc/00292/40357/82998.pdf |
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| Thomas, Elizabeh R; Allen, Claire S; Etourneau, Johan; King, Amy Cf; Severi, Mirko; Winton, V. Holly L.; Mueller, Juliane; Crosta, Xavier; Peck, Victoria L.. |
| Dramatic changes in sea ice have been observed in both poles in recent decades. However, the observational period for sea ice is short, and the climate models tasked with predicting future change in sea ice struggle to capture the current Antarctic trends. Paleoclimate archives, from marine sedimentary records and coastal Antarctic ice cores, provide a means of understanding sea ice variability and its drivers over decadal to centennial timescales. In this study, we collate published records of Antarctic sea ice over the past 2000 years (2 ka). We evaluate the current proxies and explore the potential of combining marine and ice core records to produce multi-archive reconstructions. Despite identifying 92 sea ice reconstructions, the spatial and temporal... |
| Tipo: Text |
Palavras-chave: Sea ice; Antarctica; Paleoclimate; Ice cores; Marine sediments. |
| Ano: 2019 |
URL: https://archimer.ifremer.fr/doc/00595/70709/68916.pdf |
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| Dehnhard, Nina; Achurch, Helen; Clarke, Judy; Michel, Loic; Southwell, Colin; Sumner, Michael D.; Eens, Marcel; Emmerson, Louise. |
| 1.Ecological niche theory predicts sympatric species to show segregation in their spatio‐temporal habitat utilization or diet as a strategy to avoid competition. Similarly, within species individuals may specialise on specific dietary resources or foraging habitats. Such individual specialisation seems to occur particularly in environments with predictable resource distribution and limited environmental variability. Still little is known about how seasonal environmental variability affects segregation of resources within species and between closely related sympatric species. 2.The aim of the study was to investigate the foraging behaviour of three closely related and sympatrically breeding fulmarine petrels (Antarctic petrels Thalassoica antarctica, cape... |
| Tipo: Text |
Palavras-chave: Antarctica; Biologging; Expectation-Maximization binary Clustering (EMbC); Fulmarine petrel; Generalized additive model (GAM); Kernel distribution; Model cross-validation; Stable isotope analysis. |
| Ano: 2020 |
URL: https://archimer.ifremer.fr/doc/00509/62056/66218.pdf |
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| Cowart, Dominique; Murphy, Katherine R.; Cheng, C. -h. Christina. |
| The West Antarctic Peninsula (WAP) is the fastest warming region in Antarctica where climate impact on the cold-adapted marine ecosystem is already visible. To monitor faunal changes in remote vast bodies of Antarctic waters, efficient and informative tools are essential. High-throughput sequencing of environmental DNA (eDNA) has emerged as one such tool for monitoring biodiversity and ecosystems, as it increases detection sensitivity of taxa, and sampling is often simpler and less costly than traditional collection methods. We collected water samples from four WAP shallow (≤ 300 m) shelf regions, recovered the eDNA therein, and performed metagenomic shotgun sequencing and analyses to determine the effectiveness of this method to assess marine benthic... |
| Tipo: Text |
Palavras-chave: EDNA; Antarctica; Metagenomics; King crabs; Benthic invertebrates. |
| Ano: 2018 |
URL: http://archimer.ifremer.fr/doc/00413/52490/53278.pdf |
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| Ainley, Dg; Hobson, Ka; Crosta, X; Rau, Gh; Wassenaar, Li; Augustinus, Pc. |
| Here we present first time evidence for concordant variation in the isotopic signature at both the base and the upper levels of the Antarctic coastal food web during the Holocene. Laminae in sub-fossil deposits of snow petrel Pagodroina nivea stomach oil, known as mumiyo, were collected from nest-sites in the Bunger Hills, East Antarctica. Mumiyo layers were sub-sampled, radiocarbondated, and analyzed for delta C-13 and delta D. The obtained values were compared to isotopic variability among layers of an ocean sediment core collected, and similarly dated, in nearby Dumont D'Urville Trough. Overlapping records extended from about 10 160 to 526 calendar years before present (cal yr BP). Mumiyo delta D values remained relatively constant throughout the... |
| Tipo: Text |
Palavras-chave: Antarctica; Holocene climate change; Food webs; Isotopic analysis; Mumiyo; Pagodroma nivea; Sediment cores; Snow petrel. |
| Ano: 2006 |
URL: https://archimer.ifremer.fr/doc/00496/60808/64708.pdf |
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| Registros recuperados: 78 | |
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