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Main Islands (main + island)
Selected AbstractsHelicobacter pylori and Hepatitis a Virus Infection in School-Aged Children on Two Isolated Neighborhood Islands in TaiwanHELICOBACTER, Issue 3 2003Liang-Kung Chen ABSTRACT Background. The transmission routes of Helicobacter pylori and hepatitis A virus (HAV) infections have been extensively discussed in previous literature. However, whether H. pylori and HAV shared the same transmission pattern or not remains unclear. Lower socioeconomic status was recognized as a consistent risk factor to both infections. However, whether fecal-oral transmission was a risk factor to both infections is still under debate. Materials and Methods. In 1996, we conducted a cross-sectional study to evaluate the seroprevalence of antibody to H. pylori and HAV among the randomly selected school-aged children (age between 13 and 15) on Green Island (n = 91) and Lanyu Island (n = 138) (two isolated neighborhood islands near Taiwan Main Island). Results. The seroprevalence of H. pylori and HAV on the Green Island were 82.4% and 5.5%, respectively. The seroprevalence of H. pylori and HAV on Lanyu Island were 71.0% and 90.6%, respectively. H. pylori seroprevalence of all children and the subgroup of 13-year-olds was significantly lower on Lanyu Island than Green Island. However, it was not significantly different in subgroups of 14- and 15-year-olds. HAV seroprevalence was significantly higher on Lanyu Island than Green Island among all children and in each age subgroup. The correlation of H. pylori infection and HAV infection did not demonstrate significant linear correlation on both islands. Conclusions. In conclusion, H. pylori and HAV infections in school-aged children of 13,15 years of age on Green Island and Lanyu Island did not demonstrate significant correlation. The results of this study imply that H. pylori and HAV may share different transmission routes of infection. [source] Evolution rampant: house mice on MadeiraMOLECULAR ECOLOGY, Issue 21 2009R. J. BERRY House mice are extra-ordinary animals ,extra -ordinary in the literal sense of that word. They are pests , but also a valued laboratory animal. They are generalized rodents , and successful in habitats from tundra to tropics and from sea-level to high altitudes. They have differentiated into a perplexity of taxa, yet differ little in their general morphology. They were long scorned by ecologists as recently arrived commensals, but are increasingly illuminating evolutionary processes as new techniques are applied to their study. Local forms, once valued only by taxonomists, are proving ever more interesting as their genetics are probed. In 1992, Mathias & Mira described the apparently unexciting characteristics of mice living on the two main islands of the Madeira group, 600 km west of continental Portugal. Then in 2000, Britton-Davidian et al. discovered that there were at least six chromosomal (Robertsonian) races on the main island. In the past decade, studies of molecular and mitochondrial genomes have shown an array of variables and posed questions about the origins and subsequent evolution of these island mice. In this issue of Molecular Ecology, Förster et al. report on the mtDNA haplotypes found on the island and in mainland Portugal, discuss the probable source of the island colonizers, and consider data which might give information about the timing of the colonizing event(s). [source] THE LAST GLACIATION OF SHETLAND, NORTH ATLANTICGEOGRAFISKA ANNALER SERIES A: PHYSICAL GEOGRAPHY, Issue 1 2008N.R. GOLLEDGE ABSTRACT. Evidence relating to the extent, dynamics, and relative chronology of the last glaciation of the Shetland Islands, North Atlantic, is presented here, in an attempt to better illuminate some of the controversies that still surround the glacial history of the archipelago. We appraise previous interpretations and compare these earlier results with new evidence gleaned from the interpretation of a high resolution digital terrain model and from field reconnaissance. By employing a landsystems approach, we identify and describe three quite different assemblages of landscape features across the main islands of Mainland, Yell and Unst. Using the spatial interrelationship of these landsystems, an assessment of their constituent elements, and comparisons with similar features in other glaciated environments, we propose a simple model for the last glaciation of Shetland. During an early glacial phase, a coalescent British and Scandinavian ice sheet flowed approximately east to west across Shetland. The terrestrial land-forms created by this ice sheet in the north of Shetland suggest that it had corridors of relatively fast-flowing ice that were partially directed by bed topography, and that subsequent deglaciation was interrupted by at least one major stillstand. Evidence in the south of Shetland indicates the growth of a local ice cap of restricted extent that fed numerous radial outlet glaciers during, or after, ice-sheet deglaciation. Whilst the absolute age of these three landsystems remains uncertain, these new geo-morphological and palaeoglaciological insights reconcile many of the ideas of earlier workers, and allow wider speculation regarding the dynamics of the former British ice sheet. [source] How to go extinct: lessons from the lost plants of KrakatauJOURNAL OF BIOGEOGRAPHY, Issue 5 2000Robert J. Whittaker Abstract Aim Few data sets exist that allow measurement of long-term extinction and turnover rates for islands of the size of the three main islands of the Krakatau group. We test the reliability of previous estimates of plant species extinction and examine structure within the extinction data. Location The data analysed are for the three older Krakatau islands: Rakata, Sertung and Panjang in the Sunda Strait, Indonesia. Methods Our analysis is based on a comprehensive database incorporating all species records for each island since recolonization began after the 1883 sterilization, plus attributes such as distribution, phylogeny, population status and dispersal mechanism for each species. We employ a combination of univariate and multi-term analyses in analysing structure, and derive Minimal Adequate Models using binary logistic analyses of variance and covariance. We compare the 1883,1934 data set with the contemporary flora as represented by (1) 1979,83 records (as used in previous analyses) and (2) 1979,94 data (original). Results The improved data for the contemporary flora reduces the number of missing species by one-third. We show that a variety of estimates of extinction rate can be produced depending on what assumptions are made concerning the status of particular species groups. Structural features in the extinction data persist despite the reduction in overall numbers of losses. Losses relate to: (1) the number of islands on which a species originally occurred, (2) the primary dispersal mode, and (3) the original abundance of a species (e.g. whether it was known to have established a successful resident population, and whether it was in decline or increasing in c. 1930). The ,best' descriptive model employs the variables denoted under (3). A high proportion of losses comprised species introduced by people and rare or ephemeral species. Losses of ,residents' that had colonized naturally could largely be accounted for by reference to (1) successional loss of habitat and, to a lesser degree, (2) other habitat disturbance or loss. Main conclusions Previous analyses, based on a more limited data set, have significantly over-estimated extinction from the Krakatau flora. Few naturally colonizing and established species have become extinct. The findings indicate that caution is necessary in interpreting ,headline' island ecological rates, and in analysing and modelling such data. Examination of structural features of the data appear to be valuable both in providing ecological insights in their own right, and in enabling refinements to estimates of extinction and thus turnover. [source] Differentiation of golden-ringed dragonfly Anotogaster sieboldii (Selys, 1854) (Cordulegastridae: Odonata) in the insular East Asia revealed by the mitochondrial gene genealogy with taxonomic implicationsJOURNAL OF ZOOLOGICAL SYSTEMATICS AND EVOLUTIONARY RESEARCH, Issue 2 2008T. Kiyoshi Abstract Molecular phylogeographical analyses of Anotogaster sieboldii (Selys, 1854) were conducted to reveal the differentiation process of insular populations. The gene genealogy based on 845 bp of the mitochondrial genes (cytochrome oxidase subunit I and subunit II) indicated that A. sieboldii includes two deeply separated lineages. These two major lineages seem to have differentiated in Miocene before the formation of the insular East Asia. One lineage includes three inner clades that correspond to the populations of northern area (the Japanese main islands, Korean Peninsula, Yakushima), Amamioshima and Okinawajima. Populations of Central Ryukyu, including Amamioshima and Okinawajima, might have been divided from the northern populations in early Pleistocene. The other major lineage includes populations of the Yaeyama Group, Taiwan and East China. The former two populations were reconstructed as a reciprocal monophyletic group. Populations of Taiwan and Yaeyama Groups would have been separated from the continental ones in Pleistocene. These two highly divergent lineages should be recognized as distinct species. Furthermore, the mitochondrial lineages revealed six genetically distinct and geographically isolated assemblages: (1) northern populations, (2) Amamioshima, (3) Okinawajima, (4) Yaeyama Group, (5) Taiwan and (6) East China. Zusammenfassung An der Libelle Anotogaster sieboldii wurden molekulare phylogeographische Analysen durchgeführt, um ihre Differenzierungen in Insel-Populationen zu erkennen. Die Gen-Genealogie (basierend auf 845 bp mitochondrialer Gene (COI und COII) zeigte, dass A. sieboldii zwei weit getrennte Abstammungslinien enthält, die sich wahrscheinlich im Miozän vor der Bildung der ostasiatischen Inselwelt differenzierten. Eine Abstammungslinie schließt drei Gruppierungen ein, die den Populationen in den nördlichen Gebieten entsprechen: die japanischen Hauptinseln, die koreanische Halbinsel Yakushima, Amamioshima sowie Okinawajima. Die Populationen von Zentral-Ryukyu, einschließlich Amamioshima und Okinawajima, ist möglicherweise im frühen Pleistozän von den nördlichen Populationen getrennt worden. Die andere größere Abstammungslinie schließt die Populationen der Yaeyama-Gruppe, Taiwan und das Östliche China ein. Zwei dieser Populationen wurden als Teil einer entsprechenden monophyletischen Gruppe rekonstruiert; die Populationen von Taiwan und die Yaeyama-Gruppe sind danach im Pleistozän von den kontinentalen Populationen getrennt worden. Diese zwei sehr differierenden Abstammungslinien sollten als verschiedene Spezies betrachtet werden. Weiterhin werden sechs genetisch verschiedene und geographisch isolierte Gruppierungen deutlich: (1) die nördlichen Populationen, (2) Amamioshima, (3) Okinawajima, (4) die Yaeyama-Gruppe, (5) Taiwan und (6) die Population im östlichen China. [source] Evolution rampant: house mice on MadeiraMOLECULAR ECOLOGY, Issue 21 2009R. J. BERRY House mice are extra-ordinary animals ,extra -ordinary in the literal sense of that word. They are pests , but also a valued laboratory animal. They are generalized rodents , and successful in habitats from tundra to tropics and from sea-level to high altitudes. They have differentiated into a perplexity of taxa, yet differ little in their general morphology. They were long scorned by ecologists as recently arrived commensals, but are increasingly illuminating evolutionary processes as new techniques are applied to their study. Local forms, once valued only by taxonomists, are proving ever more interesting as their genetics are probed. In 1992, Mathias & Mira described the apparently unexciting characteristics of mice living on the two main islands of the Madeira group, 600 km west of continental Portugal. Then in 2000, Britton-Davidian et al. discovered that there were at least six chromosomal (Robertsonian) races on the main island. In the past decade, studies of molecular and mitochondrial genomes have shown an array of variables and posed questions about the origins and subsequent evolution of these island mice. In this issue of Molecular Ecology, Förster et al. report on the mtDNA haplotypes found on the island and in mainland Portugal, discuss the probable source of the island colonizers, and consider data which might give information about the timing of the colonizing event(s). [source] Phylogeography of the Japanese giant flying squirrel, Petaurista leucogenys (Rodentia: Sciuridae): implication of glacial refugia in an arboreal small mammal in the Japanese IslandsBIOLOGICAL JOURNAL OF THE LINNEAN SOCIETY, Issue 1 2009TATSUO OSHIDA To test the association between temperate forest dynamics and glacial refugia for arboreal small mammals, we studied the phylogeography of the Japanese giant flying squirrel (Petaurista leucogenys) using complete mitochondrial cytochrome b gene sequences (1140 bp). This squirrel is endemic to three of Japan's main islands: Honshu, Shikoku, and Kyushu. We examined 58 specimens of P. leucogenys collected from 40 localities in Japan. Additionally, two individuals with unknown sampling localities were included in phylogenetic analyses. There were 54 haplotypes of P. leucogenys. We found five major phylogroups (Northern, Central, South-eastern, South-western, and Southern). These phylogroups may have originated from glacial refugia during the Late Pleistocene. After the last glaciation, the Northern phylogroup, widely distributed in eastern Japan, could have extensively expanded northward from its refugia. By contrast, in western Japan, population expansion was restricted to western Japan. All members of four phylogroups existed in western Japan during glaciations. The complicated phylogeographical pattern of P. leucogenys populations originating from western Japan may have resulted from the long history. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society, 2009, 98, 47,60. [source] | |||||||||||||