895 resultados para Symbolism of the South


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Coccolithophore contributions to the global marine carbon cycle are regulated by the calcite content of their scales (coccoliths), and the relative cellular levels of photosynthesis and calcification. All three of these factors vary between coccolithophore species, and with response to the growth environment. Here, water samples were collected in the northern basin of the South China Sea (SCS) during summer 2014 in order to examine how environmental variability influenced species composition and cellular levels of calcite content. The vertical structure of the coccolithophore community was strongly regulated by mesoscale eddies. All living coccolithophores produced within the euphotic zone (1 % of surface irradiance), and Florisphaera profunda was a substantial coccolithophore and coccolith-calcite producer in the Deep Chlorophyll-a Maximum (DCM), especially in most oligotrophic anti-cyclonic eddy centers. Placolith-bearing coccolithophores, plus F. profunda, and other larger and numerically rare species made almost equal contributions to coccolith-based calcite in the water column. For Emiliania huxleyi biometry measurements, coccolith size positively correlated with nutrients, and it is suggested that coccolith length is influenced by nutrient and light related growth rates. However, larger sized coccoliths were related to low pH and calcite saturation, although it is not a simple cause and effect relationship. Genotypic or ecophenotypic variation may also be linked to coccolith size variation.

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Este estudo tem como objetivo investigar os impactos da oscilação de Madden-Julian (OMJ) na precipitação da região Nordeste do Brasil (NEB). Para tanto foram utilizados dados diários de precipitação baseados em 492 pluviômetros distribuídos na região e cobrindo um período de 30 anos (1981 − 2010). As análises através de composições de anomalias de precipitação, radiação de onda longa e fluxo de umidade, foram obtidas com base no índice da OMJ desenvolvido por Jones-Carvalho. Para distinguir o sinal da OMJ de outros padrões de variabilidade climática, todos os dados diários foram filtrados na escala de 20 − 90 dias; portanto somente dias classificados como eventos da OMJ foram considerados nas composições. Uma análise preliminar baseada apenas nos dados de precipitação foi feita para uma pequena área localizada no interior semiárido do NEB, conhecida como Seridó. Essa microrregião é uma das áreas mais secas do NEB e foi reconhecida pela Convenção das Nações Unidas para o Combate à Desertificação e Mitigação dos Efeitos das Secas como particularmente vulnerável à desertificação. Composições de anomalias de precipitação foram feitas para cada uma das oito fases da OMJ durante Fevereiro-Maio (principal período chuvoso da microrregião). Os resultados mostraram a existência de variações significativas nos padrões de precipitação (de precipitação excessiva à deficiente) associados à propagação da OMJ. A combinação dos sinais de precipitação obtidos durantes as fases úmidas e secas da OMJ mostrou que a diferença corresponde cerca de 50 − 150% de modulação das chuvas na microrregião. Em seguida, uma investigação abrangente sobre o papel da OMJ sobre toda a região Nordeste foi feita considerando-se as quatro estações do ano. Os resultados mostraram que os impactos da OMJ na precipitação intrassazonal do NEB apresentam forte sazonalidade. A maior coerência espacial dos sinais de precipitação ocorreram durante o verão austral, quando cerca de 80% das estações pluviométricas apresentaram anomalias positivas de precipitação durante as fases 1 − 2 da OMJ e anomalias negativas de precipitação nas fases 5 − 6 da oscilação. Embora impactos da OMJ na precipitação intrassazonal tenham sido encontrados na maioria das localidades e em todas as estações do ano, eles apresentaram variações na magnitude dos sinais e dependem da fase da oscilação. As anomalias de precipitação do NEB observadas são explicadas através da interação existente entre as ondas de Kelvin-Rossby acopladas convectivamente e as características climáticas predominantes sobre a região em cada estação do ano. O aumento de precipitação observado sobre a maior parte do NEB durante o verão e primavera austrais encontra-se associado com o fluxo de umidade de oeste (regime de oeste), o qual favorece a atividade convectiva em amplas áreas da América do Sul tropical. Por outro lado, as anomalias de precipitação durante o inverno e outono austrais apresentaram uma variabilidade espacial mais complexa. Durante estas estações, as anomalias de precipitação observadas nas estações localizadas na costa leste do NEB dependem da intensidade do anticiclone do Atlântico Sul, o qual é modulado em grande parte por ondas de Rossby. As características topográficas do NEB parecem desempenhar um papel importante na variabilidade observada na precipitação, principalmente nestas áreas costeiras. A intensificação do anticiclone aumenta a convergência dos ventos alísios na costa contribuindo para a ocorrência de precipitação observada à barlavento do planalto da Borborema. Por outro lado, o aumento da subsidência parece ser responsável pelos déficits de precipitação observados à sotavento. Tais condições mostraram-se típicas durante o predomínio do regime de leste sobre a região tropical da América do Sul e o NEB, durante o qual ocorre uma diminuição no fluxo de umidade proveniente da Amazônia.

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We present 30 new planktonic foraminiferal census data of surface sediment samples from the South China Sea, recovered between 630 and 2883 m water depth. These new data, together with the 131 earlier published data sets from the western Pacific, are used for calibrating the SIMMAX-28 transfer function to estimate past sea-surface temperatures. This regional SIMMAX method offers a slightly better understanding of the marginal sea conditions of the South China Sea than the linear transfer function FP-12E, which is based only on open-ocean data. However, both methods are biased toward the tropical temperature regime because of the very limited data from temperate to subpolar regions. The SIMMAX formula was applied to sediment core 17940 from the northeastern South China Sea, with sedimentation rates of 20-80 cm/ka. Results revealed nearly unchanged summer temperatures around 28°C for the last 30 ky, while winter temperatures varied between 19.5°C in the last glacial maximum and 26°C during the Holocene. During Termination 1A, the winter estimates show a Younger Dryas cooling by 3°C subsequent to a temperature optimum of 24°C during the Bölling=Alleröd. Estimates of winter temperature differences between 0 and 100 m water depth document the seasonal variations in the thickness of the mixed layer and provide a new proxy for estimating past changes in the strength of the winter monsoon.

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Paleotopographic models of the West Antarctic margin, which are essential for robust simulations of paleoclimate scenarios, lack information on sediment thickness and geodynamic conditions, resulting in large uncertainties. A new total sediment thickness grid spanning the Ross Sea-Amundsen Sea-Bellingshausen Sea basins is presented and is based on all the available seismic reflection, borehole, and gravity modeling data offshore West Antarctica. This grid was combined with NGDC's global 5 arc minute grid of ocean sediment thickness (Whittaker et al., 2013, doi:10.1002/ggge.20181) and extends the NGDC grid further to the south. Sediment thickness along the West Antarctic margin tends to be 3-4 km larger than previously assumed. The sediment volume in the Bellingshausen, Amundsen, and Ross Sea basins amounts to 3.61, 3.58, and 2.78 million km³, respectively. The residual basement topography of the South Pacific has been revised and the new data show an asymmetric trend over the Pacific-Antarctic Ridge. Values are anomalously high south of the spreading ridge and in the Ross Sea area, where the topography seems to be affected by persistent mantle processes. In contrast, the basement topography offshore Marie Byrd Land cannot be attributed to dynamic topography, but rather to crustal thickening due to intraplate volcanism. Present-day dynamic topography models disagree with the presented revised basement topography of the South Pacific, rendering paleotopographic reconstructions with such a limited dataset still fairly uncertain.

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The Southern Ocean ecosystem at the Antarctic Peninsula has steep natural environmental gradients, e.g. in terms of water masses and ice cover, and experiences regional above global average climate change. An ecological macroepibenthic survey was conducted in three ecoregions in the north-western Weddell Sea, on the continental shelf of the Antarctic Peninsula in the Bransfield Strait and on the shelf of the South Shetland Islands in the Drake Passage, defined by their environmental envelop. The aim was to improve the so far poor knowledge of the structure of this component of the Southern Ocean ecosystem and its ecological driving forces. It can also provide a baseline to assess the impact of ongoing climate change to the benthic diversity, functioning and ecosystem services. Different intermediate-scaled topographic features such as canyon systems including the corresponding topographically defined habitats 'bank', 'upper slope', 'slope' and 'canyon/deep' were sampled. In addition, the physical and biological environmental factors such as sea-ice cover, chlorophyll-a concentration, small-scale bottom topography and water masses were analysed. Catches by Agassiz trawl showed high among-station variability in biomass of 96 higher systematic groups including ecological key taxa. Large-scale patterns separating the three ecoregions from each other could be correlated with the two environmental factors, sea-ice and depth. Attribution to habitats only poorly explained benthic composition, and small-scale bottom topography did not explain such patterns at all. The large-scale factors, sea-ice and depth, might have caused large-scale differences in pelagic benthic coupling, whilst small-scale variability, also affecting larger scales, seemed to be predominantly driven by unknown physical drivers or biological interactions.

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The relationship between the abundance and diversity of tintinnids and the concentration of chlorophyll a (Chl a) was contrasted between neritic and oceanic waters of the SW Atlantic during autumn and summer. Chl a and tintinnid abundance and biomass reached maximum values (17.53 µg/L, 2.76 x 10**3 ind./L and 6.29 µg C/L, respectively) in shelf waters during summer, and their mean values generally differed by one order of magnitude between environments. Peaks in species richness (13) and Shannon diversity index (2.12) were found in the shelf-ocean boundary, but both variables showed nonsignificant differences between areas. Species richness correlated significantly with both Chl a and abundance. Such relationships, which followed a negative linear or quadratic function in the shelf and a positive linear function in oceanic waters, are thought to reflect either the competitive dominance of one species or a relatively wide spectrum of tintinnid size-classes, respectively.

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Fossil associations from the middle and upper Eocene (Bartonian and Priabonian) sedimentary succession of the Pamplona Basin are described. This succession was accumulated in the western part of the South Pyrenean peripheral foreland basin and extends from deep-marine turbiditic (Ezkaba Sandstone Formation) to deltaic (Pamplona Marl, Ardanatz Sandstone and Ilundain Marl formations) and marginal marine deposits (Gendulain Formation). The micropalaeontological content is high. It is dominated by foraminifera, and common ostracods and other microfossils are also present. The fossil ichnoasssemblages include at least 23 ichnogenera and 28 ichnospecies indicative of Nereites, Cruziana, Glossifungites and ?Scoyenia-Mermia ichnofacies. Body macrofossils of 78 taxa corresponding to macroforaminifera, sponges, corals, bryozoans, brachiopods, annelids, molluscs, arthropods, echinoderms and vertebrates have been identified. Both the number of ichnotaxa and of species (e. g. bryozoans, molluscs and condrichthyans) may be considerably higher. Body fossil assemblages are comparable to those from the Eocene of the Nord Pyrenean area (Basque Coast), and also to those from the Eocene of the west-central and eastern part of South Pyrenean area (Aragon and Catalonia). At the European scale, the molluscs assemblages seem endemic from the Pyrenean area, although several Tethyan (Italy and Alps) and Northern elements (Paris basin and Normandy) have been recorded. Palaeontological data of studied sedimentary units fit well with the shallowing process that throughout the middle and late Eocene occurs in the area, according to the sedimentological and stratigraphical data.

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This thesis deals with the origins of the architectural forms as expressed in the Homeric Mycenaean citadel. The Genesis of the Mycenaean Citadel is a philosophical quest which reveals the poetic dimension of the Mycenaean architecture. The Introduction deals with general theories on the subject of space, which converge into one, forming the spinal idea of the thesis. The ‘process of individuation’, the process by which a person becomes ‘in-dividual’ that is a separate, indivisible unity or ‘whole’, is a process of transformation and renewal which at collective level takes place within the citadel. This is built on the archetype which expresses both the nature of the soul as a microcosm and of the divinely ordered Cosmos. The confrontation of the rational ‘ego’ with the unconscious is the process which brings us to the ‘self’, that organising center of the human psyche which is symbolised through the centre of the citadel. . Chapter I refers to ‘the Archetype of the Mycenaean citadel’. The Mycenaean citadel, which is built on a certain pattern of placement and orientation in relation to landscape formations, reproduces images which belong to the category of the ‘archetypal mother’. On the other hand, its adjustment to a central point with ‘high’ significance, recalls the archetypal image of Shiva-Shakti. The citadel realises the concept of a Kantian ‘One-all embracing space’; it is a cosmogonic symbol but also a philosophical one. Chapter II examines the column in its dual meaning, which is expressed in one structure; column and capital unite within their symbolism the conscious and unconscious contents of the human psyche and express the archetype of wholeness and goal of the individuation process. 33 Chapter III is a philosophical research into thesymbolism of the triangle’, the sacred Pythagorean symbol which expresses certain cosmological beliefs about the relation between human nature and the divinely ordered Cosmos. The triangular slab over the Lion Gate is a representation of the Dionysiac ‘palingenesia’, that is the continuity of One life, which was central to the Mycenaean religion. Chapter IV deals with the tripartite ‘megaron’. The circular hearth within the four-columned hall expresses the ‘quaternity of the One’, one of the oldest religious symbols of humanity. Zeus is revealed in the ‘fiery monadic unit-cubit’ as an all-embracing god next to goddess Hestia, symbolised by the circular hearth. The ‘megaron’ expresses the alchemical quaternity and the triad but also the psychological stages of development in the process towards wholeness. In the Conclusions it is emphasised that the Mycenaean citadel was created as if in a repetition of a cosmogony. It is a ‘mandala’, the universal image which is identified with God-image in man. Moreover it is built in order to be experienced by its citizen in the process of his psychological transformation towards the ‘self’, the divine element within the psyche which unites with the divinely ordered Cosmos

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To determine good ecological status and conservation of the Sub-Marine area of the Bay of Biscay, the implementation of a new rocky intertidal habitats monitoring is needed. A protocol has been adapted from the Brittany protocol for the water body FRFC11 "Basque coast" for the two indicators "intertidal macroalgae" and "subtidal macroalgae" under the Water Framework Directive to qualify the ecological. However no protocol has been validated for fauna in front of meridional characters of the benthic communities. Investigations carried out on macroalgae communities on intertidal area in WFD framework, since 2008, constitute an important working basis. This is the aim of the Bigorno project (Intertidal Biodiversity of the south of the Bay of Biscay and Observation for New search and Monitoring for decision support), financed by the Agency of Marine Protected Areas and the Departmental Council. To implement knowledge, a sampling protocol has been used in 2015 on the boulder fields of Guéthary. This site is part of Natura 2000 area "rocky Basque coast and offshore extension "It constitutes also a Znieff site and restricted fishing area. The sampling strategy considers the heterogeneity of substrates and the presence of intertidal microhabitats. Two main habitats are present: "mediolittoral rock in exposed area habitat" and "boulder fields". Habitat "intertidal pools and permanent ponds" is also present but, it is not investigated. Sampling effort is of 353 quadrats of 0.1 m², drawn randomly according to a spatially stratified sampling plan, defined by habitat and algal belts. Taxa identification and enumeration are done on each quadrat. The objective of this work is to expose results from data collected during 2015 sampling program. The importance of characterizing benthic fauna communities spatial distribution belonging to the Basque coast according to algal belts defines during the WDF survey was highlighted. Concurrently, indicators of biodiversity were studied.

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L’étude conceptualise la symbolique du Sud en tant qu’espace identitaire construit par une idéologie politique et une esthétique. Les cartes géographiques inversées (1936, 1943) de Joaquín Torres García (Uruguay) sont une prise de position politique qui affirme le pouvoir d’énonciation des artistes latino-américains de façon indépendante aux centres culturels européens. Sa théorie, l’« Universalisme Constructif », propose un nouvel art pour l’Amérique latine, combinant l’éthique artistique précolombienne et l’abstraction moderniste. Dans la nouvelle « Le Sud » (1953) et l’essai « L’écrivain argentin et la tradition » (1951), Jorge Luis Borges (Argentine) redéfinit la littérature latino américaine, marginalisée et périphérique, en tant que littérature qui a droit à toute la culture occidentale. Il rejette une culture qui ne serait que nationaliste. Le diptyque de Fernando Solanas (Argentine) formé des films Sud (1985) et Tangos, l’exil de Gardel (1988) est étudié à partir de son manifeste « Vers un Tiers- Cinéma » (1969), coécrit avec Octavio Getino. Dans le diptyque, le Sud est un espace de dénonciation des censures de la dictature et de l’impérialisme, mais aussi un espace de rénovation culturelle et identitaire. Dans son cinéma, Solanas utilise un produit culturel régional, le tango, comme outil de dénonciation politique. Tout au long de l’étude, on utilise des notions de Michel Foucault, (hétérotopie) et de Walter Mignolo (le centre amovible) pour approfondir le sens de l’espace Sud.

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El Niño South Oscillation (ENSO) is one climatic phenomenon related to the inter-annual variability of global meteorological patterns influencing sea surface temperature and rainfall variability. It influences human health indirectly through extreme temperature and moisture conditions that may accelerate the spread of some vector-borne viral diseases, like dengue fever (DF). This work examines the spatial distribution of association between ENSO and DF in the countries of the Americas during 1995-2004, which includes the 1997-1998 El Niño, one of the most important climatic events of 20(th) century. Data regarding the South Oscillation index (SOI), indicating El Niño-La Niña activity, were obtained from Australian Bureau of Meteorology. The annual DF incidence (AIy) by country was computed using Pan-American Health Association data. SOI and AIy values were standardised as deviations from the mean and plotted in bars-line graphics. The regression coefficient values between SOI and AIy (rSOI,AI) were calculated and spatially interpolated by an inverse distance weighted algorithm. The results indicate that among the five years registering high number of cases (1998, 2002, 2001, 2003 and 1997), four had El Niño activity. In the southern hemisphere, the annual spatial weighted mean centre of epidemics moved southward, from 6° 31' S in 1995 to 21° 12' S in 1999 and the rSOI,AI values were negative in Cuba, Belize, Guyana and Costa Rica, indicating a synchrony between higher DF incidence rates and a higher El Niño activity. The rSOI,AI map allows visualisation of a graded surface with higher values of ENSO-DF associations for Mexico, Central America, northern Caribbean islands and the extreme north-northwest of South America.

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Triatomine surveillance in rural areas, artificial ecotypes, and natural ecotopes of the cities of Caturama, Ibipitanga, Macaúbas, and Seabra in the south-central region of the Brazilian state of Bahia was carried out between 2008 and 2013. Natural infection by Trypanosoma cruzi was evaluated in the specimens collected to monitor vectors of Chagas disease. A total of 1,357 specimens were collected, and four species were identified: Triatoma sordida (83%), Triatoma lenti (16.4%), Triatoma pseudomaculata (0.5%), and Panstrongylus geniculatus (0.1%). Triatoma sordida was found in four cities, only 0.7% in intradomiciliary environments. Triatoma lenti was found only in Macaúbas; 8.5% were found in intradomiciliary environments, 88.3% in peridomiciliary environments, and 3.1% in sylvatic environments. Natural infection by T. cruzi was 0.5% for T. sordida and 3.1% T. lenti. All of these cases were found in peridomiciliary environments of Macaúbas. As the results show, triatomines were found in intradomiciliary environments in three cities that were surveyed in the south-central region of the state of Bahia. Thus, an epidemiologic survey should be performed to avoid the risk of transmission to the population.

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The growth parameters and the mortality rates of the Scomber japonicus peruanus (Chub mackerel) were studied based on monthly data of frequency of fork length classes obtained from commercial landings off the Peruvian coast from 1996 to 1998. The asymptotic body length and growth rate values obtained by the ELEFAN I (Electronic Length Frequency Analysis) ranged from 40.20 cm to 42.20 cm and from 0.38 to 0.39, respectively. The oscillation amplitude was 0.60; the Winter point values varied from 0.50 to 0.60 and the performance index from 2.79 to 2.84. The total mortality rate of the Chub mackerel obtained by the linearized catch curve oscillated between 1.68 and 3.35. The rate of fishing mortality varied from 1.16 to 2.78 and the exploitation rate from 0.68 to 0.84. The annual rate of natural mortality estimated by the Pauly's method ranged from 0.52 to 0.53. The results obtained allow us to conclude that the longevity of the Chub mackerel was slightly over seven years.

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Hanleya brachyplax Simone & Jardim in Rios, 2009 is described in detail. The species occurs off the southeastern and south coast of Brazil (São Paulo and Santa Catarina states) in depths from 250 to 408 m. It differs from its congeners in having uniform white valves; wide intermediate valves; the tail valve with straight profile in the antemucronal area, and a concave postmucronal surface; and a cream-colored girdle, covered by non-articulated spines. An anatomical investigation was also performed, showing the main muscle groups; the presence of gills in the posterior third of the pallial groove; auricle with six orifices; a very flat kidney, restricted to the posterior half of the animal; and a simple esophageal region. The odontophore has a single pair of long cartilages. The buccal musculature is also described.

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Based on previous results obtained from observations and linear wave theory analysis, the hypothesis that large-scale patterns can generate extreme cold events in southeast South America through the propagation of remotely excited Rossby waves was already suggested. This work will confirm these findings and extend their analysis through a series of numerical experiments using a primitive equation model where waves are excited by a thermal forcing situated in positions chosen according to observed convection anomalies over the equatorial region. The basic state used for these experiments is a composite of austral winters with maximum and minimum frequency of occurrence of generalized frosts that can affect a large area known as the Wet Pampas located in the central and eastern part of Argentina. The results suggest that stationary Rossby waves may be one important mechanism linking anomalous tropical convection with the extreme cold events in the Wet Pampas. The combination of tropical convection and a specific basic state can generate the right environment to guide the Rossby waves trigged by the tropical forcing towards South America. Depending on the phase of the waves entering the South American continent, they can favour the advection of anomalous wind at low levels from the south carrying cold and dry air over the whole southern extreme of the continent, producing a generalized frost in the Wet Pampa region. On the other hand, when a basic state based on the composites of minimum frosts is used, an anomalous anticyclone over the southern part of the continent generates a circulation with a south-southeast wind which brings maritime air and therefore humidity over the Wet Pampas region, creating negative temperature anomalies only over the northeastern part of the region. Under these conditions even if frosts occur they would not be generalized, as observed for the other basic state with maximum frequency of occurrence of generalized frosts.