RESUMO
Vortex flows, related to solar convective turbulent dynamics at granular scales and their interplay with magnetic fields within intergranular lanes, occur abundantly on the solar surface and in the atmosphere above. Their presence is revealed in high-resolution and high-cadence solar observations from the ground and from space and with state-of-the-art magnetoconvection simulations. Vortical flows exhibit complex characteristics and dynamics, excite a wide range of different waves, and couple different layers of the solar atmosphere, which facilitates the channeling and transfer of mass, momentum and energy from the solar surface up to the low corona. Here we provide a comprehensive review of documented research and new developments in theory, observations, and modelling of vortices over the past couple of decades after their observational discovery, including recent observations in H α , innovative detection techniques, diverse hydrostatic modelling of waves and forefront magnetohydrodynamic simulations incorporating effects of a non-ideal plasma. It is the first systematic overview of solar vortex flows at granular scales, a field with a plethora of names for phenomena that exhibit similarities and differences and often interconnect and rely on the same physics. With the advent of the 4-m Daniel K. Inouye Solar Telescope and the forthcoming European Solar Telescope, the ongoing Solar Orbiter mission, and the development of cutting-edge simulations, this review timely addresses the state-of-the-art on vortex flows and outlines both theoretical and observational future research directions.
RESUMO
This population based study was undertaken to ascertain the overall prevalence of diabetes mellitus (DM) and impaired glucose tolerance (IGT) in the elderly using the WHO criteria. The role of obesity in the development of DM or IGT has been investigated for both sexes per decade of age. Furthermore the potential for DM to increase with age, as has been suggested before, has been evaluated using the IGT as a proportion of total glucose intolerance (IGT/TGI) for the same parts of the tested sample. From the 647 persons registered as elderly people in a small town in northern Greece (total population 5875 people), 66 persons did not participate in this survey. Fifty-six subjects (9.7%) had previously diagnosed DM. The remainder were tested using fasting blood glucose measurements or an oral glucose tolerance test (OGTT). The prevalence of previously undiagnosed DM according to fasting blood glucose values or after 2 h of 75 g load values was 10.1% and 9.3%, respectively. Thus the overall prevalence of DM was 29.1% and of IGT was 15.1%. These data support an increased frequency of DM (65% previously undiagnosed) and IGT in the elderly, whereas this population's susceptibility seems to decline in the older groups for both sexes. Obesity remains a risk factor for DM and IGT particularly among the younger groups although its role has been found to decline with age.