302 resultados para Asia Oriental


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A diverse and well-preserved fossil wood assemblage is described, for the first time, from the Middle Permian Taerlang Formation and the Upper Permian Quanzijie Formation in the vicinity of the Tianshan Town, Hami City of northwestern China. On the basis of wood microstructure, the fossil woods are classified into three genera and five species, including one new genus: Prototianshanoxylon gen. nov. and two new species: Prototianshanoxylon erdaogouense sp. nov., Prototianshanoxylon hamiense sp. nov. The new genus is characterized by window-like cross-field pitting and mixed tracheid radial wall pitting that suggest a transitional type between araucarioid-type and protopinoid-type pittings.Phytogeographically, the fossil wood assemblage is characterized by an admixture of elements of both temperate Angaran (represented by wood specimens with moderately to well defined growth rings in their secondary xylem) and tropical-subtropical north subregion of the Cathaysian floras (with wood specimens lacking well-defined growth rings). Such a phytogeographically mixed fossil wood assemblage is interpreted to represent a transitional and complex climate condition between a cool temperate and tropical to subtropical zones, showing both seasonal variation and unstable climate conditions. Previously, similarly mixed floras have already been found to exist widely in northern China ranging in age from Early to Late Permian, but the mechanisms thought to be responsible for their formation were varied and remain controversial. In this study, the formation of these mixed Permian floras of North China is linked to the closure of the Tianshan-Hingan seaway coupled with the collision and amalgamation of Siberia with North China and the Tarim block, in a manner much like closing a pair of scissors with the closure of the seaway proceeding gradually and progressively from west to the east.

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A prospective 1-year observational survey was designed to assess the management and control of atrial fibrillation (AF) in eight countries within the Asia-Pacific region. Patients (N = 2,604) with recently diagnosed AF or a history of AF ≤1 year were included. Clinicians chose the treatment strategy (rhythm or rate control) according to their standard practice and medical discretion. The primary endpoint was therapeutic success. At baseline, rhythm- and rate-control strategies were applied to 35.7% and 64.3% of patients, respectively. At 12 months, therapeutic success was 43.2% overall. Being assigned to rhythm-control strategy at baseline was associated with a higher therapeutic success (46.5% vs 41.4%; P = 0.0214) and a lower incidence of clinical outcomes (10.4% vs 17.1% P < 0.0001). Patients assigned to rate-control strategies at baseline had higher cardiovascular morbidities (history of heart failure or valvular heart disease). Cardiovascular outcomes may be less dependent on the choice of treatment strategy than cardiovascular comorbidities.