A study of the equatorial -region during evening twilight using a Langmuir probe

1968 ◽  
Vol 30 (6) ◽  
pp. 1193-1202
Author(s):  
S PRAKASH ◽  
B SUBBARAYA ◽  
S GUPTA
Keyword(s):  
Langmuir Probe ◽  
Equatorial Region

Theory of low-scale mhd waves in the near equatorial region of the earth plasmasphere

2001 ◽  
Vol 7 (2s) ◽  
pp. 74-83
Author(s):  
O.S. Burdo ◽  
◽  
O.K. Cheremnykh ◽  
O.P. Verkhoglyadova ◽  
◽  
...  
Keyword(s):  
Equatorial Region ◽  
Mhd Waves ◽  
The Earth

Corneal anatomy of marine mammals

1993 ◽  
Vol 71 (11) ◽  
pp. 2282-2290 ◽  
Author(s):  
M. T. Pardue ◽  
J. G. Sivak ◽  
K. M. Kovacs
Keyword(s):  
Marine Mammals ◽  
Equatorial Region ◽  
Balaenoptera Acutorostrata ◽  
Marine Habitat ◽  
Corneal Surface ◽  
Balaenoptera Physalus ◽  
Phoca Groenlandica ◽  
Minke Whales ◽  
Transmission Electron ◽  
Ultrathin Sections

The corneal anatomy of fin whales (Balaenoptera physalus), minke whales (Balaenoptera acutorostrata), harp seals (Phoca groenlandica), ringed seals (Phoca hispida), and bearded seals (Eriganthus barbatus) was examined to determine if marine mammals have evolved specialized corneas for life in a marine habitat. One to seven eyes of each species were analyzed: paraffin sections stained with haematoxylin and eosin for light microscopy; and ultrathin sections for transmission electron microscopy. All corneas contain the five typical mammalian layers: epithelium, Bowman's layer, stroma, Descemet's membrane, and endothelium. The corneas of these marine mammals are thicker than human corneas because of a thicker stromal layer. The other layers are thinner than those found in humans, except for the epithelial layer in the bearded seal and the cetaceans where it may provide extra protection for the eye during feeding behaviour. The epithelial cells in all corneas studied have an abundance of tonofilaments, which may strengthen the cells and distribute force across the corneal surface. No special organization of collagen fibrils was found in the stroma that would offer protection from ultraviolet radiation or glare for pinnipeds when on ice. The thickness of the sclera in the cetaceans may serve to hold the inner globe of the eye in an elliptical shape, while the thinning of the sclera in the equatorial region in pinnipeds may flatten the eye in air to reduce aerial myopia.

scholarly journals Winds in the Lower Cloud Level on the Nightside of Venus from VIRTIS-M (Venus Express) 1.74 μm Images

Atmosphere ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 186
Author(s):  
Dmitry A. Gorinov ◽  
Ludmila V. Zasova ◽  
Igor V. Khatuntsev ◽  
Marina V. Patsaeva ◽  
Alexander V. Turin
Keyword(s):  
Wind Speed ◽  
Meridional Wind ◽  
Equatorial Region ◽  
Hadley Cell ◽  
Horizontal Wind ◽  
Simultaneous Increase ◽  
Volcanic Area ◽  
Infrared Thermal Imaging ◽  
Latitude Range ◽  
Lower Cloud

The horizontal wind velocity vectors at the lower cloud layer were retrieved by tracking the displacement of cloud features using the 1.74 µm images of the full Visible and InfraRed Thermal Imaging Spectrometer (VIRTIS-M) dataset. This layer was found to be in a superrotation mode with a westward mean speed of 60–63 m s−1 in the latitude range of 0–60° S, with a 1–5 m s−1 westward deceleration across the nightside. Meridional motion is significantly weaker, at 0–2 m s−1; it is equatorward at latitudes higher than 20° S, and changes its direction to poleward in the equatorial region with a simultaneous increase of wind speed. It was assumed that higher levels of the atmosphere are traced in the equatorial region and a fragment of the poleward branch of the direct lower cloud Hadley cell is observed. The fragment of the equatorward branch reveals itself in the middle latitudes. A diurnal variation of the meridional wind speed was found, as east of 21 h local time, the direction changes from equatorward to poleward in latitudes lower than 20° S. Significant correlation with surface topography was not found, except for a slight decrease of zonal wind speed, which was connected to the volcanic area of Imdr Regio.

scholarly journals Influence of Rotation on the Stellar Parameters

1993 ◽  
Vol 137 ◽  
pp. 162-164 ◽  
Author(s):  
V. Wenske ◽  
D. Schönberner
Keyword(s):  
Lower Surface ◽  
Equatorial Region ◽  
Star Formation History ◽  
Rotational Rate ◽  
Visible Part ◽  
Photometric Observations ◽  
Formation History ◽  
Inclination Angles ◽  
Stellar Models ◽  
Stellar Masses

For several years it has become quite common to derive stellar parameters like effective temperature, Teff, and surface acceleration, g, by means of properly calibrated photometric indices, and to use these values for the derivation of important properties of stellar aggregates (viz. ages, star formation history, distances, etc.). Photometric observations, however, fail to give informations about one important property of a star: its rotational rate!The main effect of rotation is to increase the size of the star, mainly in the equatorial region, leading to lower surface temperatures and accelerations. Since in non–spherical stars Teff and g depend on the latitude, the observed values, which are, of course, averages over the visible hemisphere, depend on the angle of inclination, i. Collins & Sonneborn (1977) utilized the rigidly rotating stellar models of Sackmann and Anand (1970) to compute emergent fluxes and photometric indices for various stellar masses, inclination angles i and rotational parameters being the break–up rotational rate. These indices, viz. C0 and β, represent then averages over the visible part of the rotally distorted stellar models. Closer inspections indicated also that emergent fluxes and line profiles of rotationally distorted stars can be matched by the predictations of standard model atmospheres to a very high accuray, even for w close to unity (Wenske 1992, Diplom Thesis).

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