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Epidemiologia e caracterização molecular do vírus da Influenza em quatro espécies de pinguins na Região Antártica. / Epidemiology and molecular characterization of the influenza virus in four penguin species of the antartic region.Luiz Francisco Sanfilippo 23 February 2011 (has links)
O Vírus da influenza, apesar de todas as epidemias e pandemias referirem-se a infecções em seres humanos, não está restrita a espécie humana e é capaz de causar debilidade ou mortalidade em várias outras espécies, incluindo cavalos, suínos, mamíferos marinhos e aves, entre outros. Estudos ecológicos das viroses de influenza conduziram a hipótese que todas as que acometem mamíferos derivam de reservatórios destes vírus em aves. Mesmo com programas de monitoramento contínuo de aves silvestres em alguns países do mundo que possuem casos originados pelos vírus aviário H5N1, pouco foi feito na Antártica e por isso, o presente trabalho foi realizado nas estações de verão antártico de 2006, 2007 e 2008 em duas localidades no território Antártico, a Península Keller, localizada na Ilha Rei George e na ilha Elefante 61°08S, 55°07W, a primeira onde está situada a Estação Antártica Comandante Ferraz-EACF e a segunda onde está localizada uma base de apoio a estudos avançados. Para este estudo foi realizada a coleta de 283 amostras de quatro diferentes espécies de pinguins: Pygoscelis adeliae; P. papua; P. antarctica; Aptenodytes patagonicus. Para o diagnóstico das amostras colhidas, foi aplicada a detecção direta dos produtos amplificados pelo método de RT-PCR em gel de agarose confirmados pelo método de Real-Time PCR (Applied Biosystems) e pelo RT-PCR-GeneScan no laboratório de Virologia Clínica e Molecular, do Departamento de Microbiologia, da Universidade de São Paulo. Os resultados obtidos em nosso estudo foram 8 amostras positivas em pinguins para o vírus Influenza A. As amostras positivas por RT-PCR foram encaminhadas para o laboratório de Influenza do Department of Infectious Diseases, St. Jude Children\'s Research Hospital, Memphis, TN, USA, para isolamento em ovos embrionados, não havendo crescimento de vírus da influenza A. Quatro destas amostras positivas puderam ser sequenciadas e comparadas com sequências de Influenza A depositadas no Genbank apresentando uma identidade de 96,8 % a 100 % entre elas e o controle tendo este último uma identidade de 100% com as do banco de dados, confirmando a presença do vírus nestas aves. / Epidemics and pandemics of influenza usually refer to infections in human beings. The influenza virus is not, however, restricted to humans and can cause infirmity and death in other species including horses, swine, marine mammals, birds, and others. Ecological studies of viral infections have led to the hypothesis that the influenza viruses that attack mammals have their origin in the accumulation of these viruses in birds (avian flu). In some countries with influenza cases caused by the avian H5N1 virus, there was monitoring of wild birds but little had been done in Antarctica. The present work was therefore carried out during the Antarctic summer seasons of 2006, 2007, and 2008 in two Antarctic locations: The Commander Ferraz Antarctic Station, on the Keller Peninsula of King George Island, and at the Base of Advanced Studies located on Elephant Island (61°08S, 55°07W). Two hundred eighty-three (283) samples from four different penguin species Pygoscelis adeliae, Pygoscelis papua, Pygoscelis antarctica; and Aptenodytes patagonicus were collected for this study. Diagnoses of the samples were performed not only by application of direct detection and amplification according to the RT-PCR method in agar-gel, but also by Real-Time PCR (Applied Biosystems), and by RT-PCR gene scan at the Laboratory of Clinical and Molecular Virology of the Department of Microbiology of the University of Sao Paulo. Eight of the penguin samples tested positive for the Influenza-A virus. The positive samples, as determined by RT-PCR, were sent to the Influenza Laboratory of the Department of Infectious Diseases of the St. Jude Research Hospital in Memphis, Tennessee, USA, to be isolated in egg embryos where no further growth of the Influenza-A virus took place. Four of these positive samples could be sequenced and compared with those of Influenza-A on deposit at the Gene Bank and ranged from 96.85 to 100% when compared with the control samples (100% positive), thus confirming the presence of the virus in the tested birds.
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Relação entre a concentração de gelo marinho Antártico e a temperatura mínima na América do Sul / Relation between the Antarctic Sea ice concentration and low temperatures in South AmericaBlank, Dionis Mauri Penning, Blank, Dionis Mauri Penning 06 March 2009 (has links)
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Previous issue date: 2009-03-06 / The Antarctic Sea Ice Concentration (ASIC) is thought to be an important element in
the analysis of the world climate. However, few studies have investigated its relation
to other climatic elements. Thus, the aim of this study was to verify the relation
between the ASIC and low temperatures in South America through two approaches.
The first, regional, investigated the occurrence of a connection between the ASIC
and the cold and hot quantiles of the daily lowest temperature as observed in some
weather stations in Rio Grande do Sul in the 1982 2005 period. For such, low
temperature values were transformed into cold and hot quantiles through the quantile
technique, and correlated to ASIC sectors. The correlation coefficient showed a
connection between the elements, with emphasis on the influence of Weddell, Ross
Sea sectors and Bellingshausen and Amundsen Sea sector, especially because the
Indian Ocean and the Western Pacific Ocean are farther away. The second
approach, continental, analyzed the ASIC variability and its connection with low
temperatures observed in South America by means of NCEP-NCAR reanalysis in the
1982 2007 period. For such, the sectors of larger ASIC variability were identified
through the principal component analysis technique, enabling the adjustment of the
ASIC-based low temperature forecasting model to South America to the data set by
the model and the observed data in the reanalysis through the multiple lineal
regression analysis technique. The prevailing areas for the explanation of ASIC
variability were found to be in the sectors above mentioned. The worst (best)
adjustment of the model occurred in the cold (hot) period, when there is a greater
(smaller) variability of low temperatures and smaller (greater) ASIC variability. / A Concentração de Gelo Marinho Antártico (CGMA) é considerada um elemento
importante na análise do clima mundial. Contudo, poucos estudos têm investigado
sua relação com outros elementos climáticos. Desse modo, o objetivo deste trabalho
consistiu em verificar a relação entre a CGMA e a temperatura mínima na América
do Sul utilizando duas abordagens. Na primeira, regional, examinou-se a existência
de conexão entre a CGMA e as classes fria e quente da temperatura mínima diária,
observada em algumas estações meteorológicas do Rio Grande do Sul, no período
de 1982 a 2005. Para isso, os dados de temperatura mínima foram transformados
em classes fria e quente, por meio da técnica dos quantis, e correlacionados com os
setores da CGMA. O coeficiente de correlação mostrou a existência de conexão
entre os elementos, com destaque para a influência dos setores dos Mares de
Weddell, de Ross e de Bellingshausen e Amundsen, até porque os setores do
Oceano Índico e do Oceano Pacífico Oeste apresentam maior distância. Na segunda
abordagem, continental, analisou-se a variabilidade da CGMA e sua ligação com a
temperatura mínima na América do Sul, observada pela reanálise do NCEP-NCAR,
no período de 1982 a 2007. Para isso, os setores de maior variabilidade da CGMA
foram identificados por intermédio da técnica de análise de componentes principais,
possibilitando o ajuste de um modelo de previsão de temperatura mínima para a
América do Sul, baseado na CGMA, com dados previstos pelo modelo e dados
observados pela reanálise, mediante o uso da técnica de análise de regressão linear
múltipla. As áreas mais predominantes na explicação da variabilidade da CGMA
foram encontradas nos setores já citados. O pior (melhor) ajuste do modelo ocorreu
no período frio (quente), onde existe maior (menor) variabilidade da temperatura
mínima e menor (maior) variabilidade da CGMA.
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Historie výskytu žábronožky Branchinecta gaini na souostroví Jamese Rosse a její fylogeografie / Historical record of the fairyshrimp Branchinecta gaini in the James Ross archipelago, and its phylogeographyPokorný, Matěj January 2017 (has links)
The Fairy shrimp Branchinecta gaini Daday, 1910 is the largest freshwater invertebrate in Antarctica and the top-level consumer of local freshwater food webs. Ecological demands of B. gaini that are accompanied by 'ruderal' life strategy together with its spatial distribution that exceeds to Patagonia indicate that it had survived last glacial period in South America and expanded to Antarctica shortly after this epoch endeed. On James Ross Island that is the most extreme environment where B. gaini occurs today was this fairy shrimp considered extinct until year 2008. Its disappearance was based on paleolimnological analysis of several lake sediment cores according to which it inhabited this island between years 4200 to approximately 1500 before present when it died out because of changes in lake catchments caused by harsh neoglacial conditions. Paleolimnological analysis of Monolith Lake presented in this study has shown that this assumption was wrong and B. gaini has lived on James Ross Island throughout neoglacial period up to recent time. Phylogeographic analysis of 16S rDNA of specimens from Patagonia, South Orkneys, South Shetlands and James Ross Island revealed that its high morphological diversity is not supported by this gene and that all examined populations of B. gaini is one species with very few...
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Atmospheric Circulation in AntarcticaWalther, Connie 31 March 2016 (has links) (PDF)
Validation of the Regional Climate Model HIRHAM with measurements, especially from radiosondes and GPS-signal-retrieval. Analysis of synoptical structures in Antarctica and comparison of the precipitation in different phases of the Antarctic Oscillation.
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Observation et simulation de la température de surface en Antarctique : application à l'estimation de la densité superficielle de la neige / Observation and simulation of surface temperature in Antartica : application in snow surface density estimationFréville, Hélène 24 November 2015 (has links)
La situation en Antarctique est complexe. Continent peu connu et isolégéographiquement,les processus qui contrôlent son bilan de masse et son bilan d'énergie sont encore mal compris. Dans ce contexte, l'étude de la température de surface connaît un intérêt grandissant de la part de la communauté scientifique. En effet, en contrôlant fortement la température de la neige jusqu'à des dizaines, voire des centaines, de mètres sous la surface, la température de surface influence l'état thermique de la calotte du plateau antarctique, sa dynamique et, par conséquent, son bilan de masse. De plus, en agissant sur les émissions de flux thermiques infrarouges et sur les flux turbulents de chaleurs sensibles et latents, la température de surface est directement liée au bilan énergétique de surface du plateau antarctique. L'analyse de la température de surface et l'étude des processus physiques à l'origine de sa variabilité participent à l'amélioration de la compréhension du bilan énergétique de surface, étape nécessaire pour déterminer l'état actuel de sa calotte et faire des prévisions sur sa potentielle contribution à l'élévation du niveau des mers. Ce travail de thèse participe à cet effort en s'intéressant au cycle diurne de la température de surface et aux différents facteurs contribuant à sa variabilité spatiale et temporelle sur le plateau antarctique. Il débute par une évaluation de différentes données entre 2000 et 2012 montrant le bon potentiel de la température de surface MODIS qui peut dès lors être utilisée comme donnée de référence pour l'évaluation des modèles et réanalyses. Un biais chaud systématique de 3 à 6°C dans la réanalyse ERA-interim de la température de surface est ainsi mis en évidence sur le plateau antarctique. L'observation du cycle diurne de la température de surface a, quant à elle, permis d'identifier la densité superficielle parmi ses facteurs de variabilité. Sur les premiers centimètres du manteau neigeux où se concentrent la majorité des échanges de masse et d'énergie entre l'atmosphère et la calotte antarctique, la densité de la neige est une donnée cruciale car elle agit sur l'absorption du rayonnement solaire dans le manteau neigeux mais également sur la conductivité thermique du manteau et donc sur la propagation de la chaleur entre la surface et les couches en profondeur. La densité superficielle de la neige présente cependant de nombreuses incertitudes sur sa variabilité spatio-temporelle et sur les processus qui la contrôlent. De plus, ne pouvant être mesurées qu'in situ, les données de densité superficielle en Antarctique sont restreintes géographiquement. Cette thèse explore une nouvelle application de la température de surface consistant à estimer la densité superficielle de la neige via une méthode d'inversion de simulations numériques. Une carte de la densité superficielle en Antarctique a ainsi pu être produite en minimisant l'erreur de simulation sur l'amplitude diurne. / The antarctic ice sheet is a key element in the climate system and an archive of past climate variations. However, given the scarcity of observations due to the geographical remoteness of Antarctica and its harsh conditions, little is known about the processes that control its mass balance and energy. In this context, several studies focus on the surface temperature which controls the snow temperature up to tens, if not hundreds, of meters beneath the surface. It also influences the thermal state of the antarctic ice sheet, its dynamics, and thus, its mass balance. Surface temperature is also directly linked to the surface energy balance through its impact on thermal and surface turbulent heat flux emissions. Thus, surface temperature analysis and the study of physical processes that control surface temperature variability contribute to the better understanding of the surface energy balance, which is a necessary step to identify the actual state of the antarctic ice sheet and forecast its impact on sea level rise. This thesis work contributes to this effort by focusing on the surface temperature diurnal cycle and various factors impacting spatial and temporal surface temperature variability on the Antarctic Plateau. First, an evaluation of MODIS data, done by comparison with in situ measurements, shows MODIS great potential in the observation of the surface temperature of the Antarctic Plateau under clear-sky conditions. Hourly MODIS surface temperature data from 2000 to 2011 were then used to evaluate the accuracy of snow surface temperature in the ERA-Interim reanalysis and the temperature produced by a stand-alone simulation with the Crocus snowpack model using ERA-Interim forcing. It reveals that ERA-Interim has a widespread warm bias on the Antarctic Plateau ranging from +3 to +6°C depending on the location. Afterwards, observations of the surface temperature diurnal cycle allow an identification of the surface density as a factor of surface temperature variability. On the topmost centimeters of the snowpack where most mass and energy exchanges between the surface and atmosphere happen, density is critical for the energy budget because it impacts both the effective thermal conductivity and the penetration depth of light. However, there are considerable uncertainties around surface density spatio-temporal variability and the processes that control it. Besides, since surface density can only be measured in situ, surface density measurements in Antarctica are restricted to limited geographical areas. Thus, this thesis also explores a new application of surface temperature by estimating surface density in Antarctica based on the monotonic relation between surface density and surface temperature diurnal amplitude. A map of surface density is obtained by minimising the simulation error related to diurnal amplitude of the surface temperature.
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Detektion langzeitiger Eismassenvariationen in der Küstenregion der OstantarktisKnöfel, Christoph 13 July 2017 (has links) (PDF)
Soll die Massenbilanz des antarktischen Eises bestimmt werden, so ist das grundlegend mit der Beobachtung dessen Geometrie, Kinematik und Dynamik verbunden. Basis dieser Arbeit sind Beobachtungen von Eisoberflächenhöhen und Fließgeschwindigkeiten im Einzugsbereich des Helen-Gletschers südlich der russischen Antarktisstation Mirnyj und im Einzugsbereich des Hays-Gletschers südöstlich der Station Molodëžnaja. 1962 wurde von Mirnyj ausgehend das sich über 100km in südliche Richtung erstreckende geodätisch-glaziologische Triangulationsnetz Mirnyj angelegt. 1972 erfolgte die Realisierung einer Traverse über das Einzugsgebiet des Hays-Gletschers. Beide Regionen wurden in den folgenden Jahren mehrfach wiederholt beobachtet. Eine erneute Wiederholungsmessung von Eisoberflächenhöhen und Fließgeschwindigkeiten konnte zwischen 2005 und 2009 realisiert werden.
Diese Arbeit beleuchtet diese Aktivitäten und beschreibt die Ableitung langzeitiger Eismassenveränderungen über Zeiträume mehrerer Dekaden. Die historische Datengrundlage, die Realisierung eines einheitlichen Bezugssystems sowie die verwendeten Beobachtungsverfahren werden ausführlich erläutert. Der Vergleich von Eisoberflächenhöhen der 2000er Jahre und Höhen der 1960er bzw. 1970er Jahre führt zur Abschätzung langzeitiger Veränderungen der Eisoberflächenhöhe für beide Regionen.
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Mezinárodní marketingová strategie nealkoholického nápoje Guaraná Antarctica / International marketing strategy of soft drink Guaraná AntarcticaKochová, Zuzana January 2010 (has links)
The thesis deals with the marketing strategy of Brazilian brand of soft drinks Guaraná Antarctica. Fisrt it describes the brand marketing strategy in the domestic market in Brazil and its entry to international markets. Furthermore the thesis analyzes market opportunities of this brand of drinks with guarana extract in Czech Republic and evaluate the trasfer of marketing strategies to Czech environment. As a result changes to the marketing strategy in order to improve brand's position on the Czech market are proposed.
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Antarctic Sea Ice Extent Reconstructions Throughout the 20th CenturySleinkofer, Amanda M. 10 September 2021 (has links)
No description available.
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Zur Bestimmung eisinduzierter Massensignale aus der Kombination geodätischer DatenGroh, Andreas 31 July 2014 (has links)
Die Kryosphäre interagiert mit verschiedenen anderen Subsystemen der Erde. Variationen der klimatischen Bedingungen führen zu kryosphärischen Massenänderungen und somit zu Änderungen des globalen Meeresspiegels. Gleichzeitig induzieren Massenvariationen des Eises und des Ozeans Deformationen der festen Erde, welche sich aus einer instantanen elastischen und einer möglichen verzögerten viskosen Reaktion (glazial-isostatischer Ausgleich – GIA) zusammensetzen. Der räumlich variable Effekt der Meeresspiegeländerung relativ zur sich deformierenden Erdkruste wird gravitativ konsistent durch die Meeresspiegelgleichung beschrieben. Er ist die entscheidende Größe zur Abschätzung des Einflusses der Meeresspiegeländerungen auf die Küsten.
Die vorliegende Arbeit widmet sich der Bestimmung rezenter Massenänderungen der Eisschilde Antarktikas (AIS) und Grönlands (GIS) mittels geodätischer Daten. Zur Ableitung der Massenbilanzen beider Eisschilde wurde auf Daten der Satellitenmission GRACE (Gravity Recovery and Climate Experiment) zurückgegriffen. Für den Zeitraum 2003/10–2009/10 konnten die Beiträge von AIS und GIS zur globalen Meeresspiegeländerung zu 0,26 ± 0,08 bzw. 0,59 ± 0,06mm/a bestimmt werden. Auf Basis wiederholter Höhenmessungen durch das Satellitenaltimeter ICESat (Ice, Cloud, and land Elevation Satellite) stand eine zweite unabhängige Schätzung der Massenbilanzen zur Verfügung. Während für den GIS beide Massenbilanzen im Rahmen der zugehörigen Fehlermaße übereinstimmen, treten für den AIS regional größere Differenzen auf. Diese konnten auf mögliche Restfehler in einer instrumentellen Korrektion der ICESat-Mission, Limitierungen der angewendeten Volumen-Massen-Umrechnung sowie auf Fehler in den genutzten GIA-Modellen zurückgeführt werden.
Für die Ableitung von Eismassenänderungen aus GRACE-Daten stellen GIA-Prädiktionen eine wichtige Reduktionsgröße dar. In Antarktika weisen verfügbare Modelle noch große Unsicherheiten auf. Für den Bereich des Amundsen-See-Sektors (Westantarktika), welcher den größten Teil zur negativen Massenbilanz des AIS beiträgt, konnte eine empirische GIA-Schätzung aus der Kombination von Massenänderungen aus GRACE und Volumenänderungen aus ICESat abgeleitet werden. Diese empirische Schätzung unterscheidet sich signifikant von den Prädiktionen verfügbarer GIA-Modelle. Eine Validierung der Ergebnisse mittels aus GPS-Beobachtungen abgeleiteten vertikalen Deformationen der Erdkruste bestätigte die empirische Schätzung. Die GPS-beobachteten Deformationen enthalten sowohl rezente eisinduzierte als auch GIA-bedingte Signalanteile. Zu deren Trennung wurden gravitativ konsistent modellierte elastische Krustendeformationen verwendet, welche auf hoch aufgelösten ICESat-Daten basieren. Insbesondere bei der Analyse von GRACE-Daten hat eine Änderung der GIA-Reduktion einen signifikanten Einfluss auf die bestimmte Massenbilanz. Im Vergleich zur Verwendung einer modellierten GIA-Reduktion ergab sich durch die Anwendung der empirischen Reduktion ein um ~40% größerer Eismassenverlust im Untersuchungsgebiet.
Sowohl in den Zeitreihen der Massenänderungen als auch in den Variationen der Eisoberflächenhöhen konnten nichtlineare Signale detektiert werden. Die Analyse von GRACE-Monatslösungen im Zeitraum 2003–2012 belegt einen erhöhten Meeresspiegelbeitrag des AIS und des GIS in den letzten Jahren. Signale dieses erhöhten Massenverlusts sind auch durch andere Sensoren detektierbar. Am Beispiel des Jakobshavn Isbræ (GIS) wurde ein beschleunigtes Fließverhalten mittels optischer Satellitendaten (Landsat) nachgewiesen und mit der beschleunigten Krustenhebung an einer benachbarten GPS-Station korreliert. Darüber hinaus wurden beobachtete Krustendeformationen auch zur Validierung der aus ICESat-Daten modellierten elastischen Deformationen genutzt. Für den Thwaites-Gletscher (AIS) konnte der Nachweis über eine Zunahme der Fließgeschwindigkeit und eine verstärkte Eishöhenabnahme durch die Hinzunahme radarbasierter Satellitendaten (TerraSAR-X, TanDEM-X) erbracht werden. Auf diese Weise war es möglich, die durch Landsat und ICESat bereitgestellten Zeitreihen zu verlängern.
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Atmospheric Circulation in Antarctica: Analysis of Synoptic Structures via Measurement and Regional Climate ModelWalther, Connie 20 November 2015 (has links)
Validation of the Regional Climate Model HIRHAM with measurements, especially from radiosondes and GPS-signal-retrieval. Analysis of synoptical structures in Antarctica and comparison of the precipitation in different phases of the Antarctic Oscillation.
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