2 resultados para Military geography--Europe, Southeastern
em Biblioteca Digital da Produção Intelectual da Universidade de São Paulo (BDPI/USP)
Resumo:
Tick-borne encephalitis virus (TBEV) is the most important arboviral agent causing disease of the central nervous system in central Europe. In this study, 61 TBEV E gene sequences derived from 48 isolates from the Czech Republic, and four isolates and nine TBEV strains detected in ticks from Germany, covering more than half a century from 1954 to 2009, were sequenced and subjected to phylogenetic and Bayesian phylodynamic analysis to determine the phylogeography of TBEV in central Europe. The general Eurasian continental east-to-west pattern of the spread of TBEV was confirmed at the regional level but is interlaced with spreading that arises because of local geography and anthropogenic influence. This spread is reflected by the disease pattern in the Czech Republic that has been observed since 1991. The overall evolutionary rate was estimated to be approximately 8x10(-4) substitutions per nucleotide per year. The analysis of the TBEV E genes of 11 strains isolated at one natural focus in Zd`ar Kaplice proved for the first time that TBEV is indeed subject to local evolution.
Resumo:
Middle to Late Holocene barriers are conspicuous landforms in southeastern and southern Brazilian regions. The barriers in the coastal zones of northern Santa Catarina, Parana and Sao Paulo states (27 degrees 19`-24 degrees 00`S) are formed mainly by beach ridge alignments and many barriers present foredune and blowout alignments in their seaward portion. The development of these eolian landforms appears to record a regional shift in coastal dynamics and barrier building. In this context, the Ilha Comprida barrier stands out for its well-developed and well-preserved foredunes and blowouts. Based on the presence or not and type of eolian landforms, the Ilha Comprida barrier can be divided seaward into inner, middle and outer units. The inner unit is formed entirely by beach ridges. The middle unit comprises a narrow belt of blowouts (up to 15 m high) aligned alongshore. Blowout lobes pointing NNW are indicative of their generation by southern winds. The outer unit is represented by low (<= 1 m high) active or stabilized foredunes and a small transgressive dunefield (similar to 1 km(2)). Twenty-seven luminescence ages (SAR protocol) obtained for the beach ridges, foredunes, and blowouts of these three units allow definition of a precise chronology of these landforms and calculation of rates of coastal progradation. The inner unit presents ages greater than 1004 +/- 88 years. The blowouts of the middle unit show ages from 575 +/- 47 to 172 +/- 18 years. The ages of the outer unit are less than 108 +/- 10 years. Rates of coastal progradation for the inner and outer units are 0.71-0.82 m/year and 0.86-2.23 m/year, respectively. The main phase of blowout development correlates well with the Little Ice Age (LIA) climatic event. These results indicate that southern winds in subtropical Brazil became increasingly more intense and/or frequent during the LIA. These conditions persist to the present and are responsible for the development of the eolian landforms in the outer unit. Thus, barrier geomorphology can record global climatic events. The sensitivity of barrier systems in subtropical Brazil to Late Holocene climate changes was favored by the relative sea level stillstand during this time. Luminescence dating makes it possible to analyze barrier geomorphology during Late Holocene climate changes operating on timescales of a hundred to thousand years. These results improve our knowledge of barrier building and will help in the evaluation of the impact of future climate changes on coastal settings. (C) 2008 Elsevier Ltd. All rights reserved.