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Coordinates of features on the Galilean satellites
The coordinate systems of each of the Galilean satellites are defined and coordinates of features seen in the Voyager pictures of these satellites are presented. The control nets of the satellites were computed by means of single block analytical triangulations. The normal equations were solved by the conjugate iterative method which is convenient and which converges rapidly as the initial estimates of the parameters are very good
Coordinates of features on the Galilean satellites
Control nets of the four Galilean satellites, established photogrammetrically from pictures taken by the two Voyager spacecraft during their flybys of Jupiter in 1979, are discussed. Coordinates of 504 points on Io, 112 points on Europa, 1547 points on Ganymede, and 439 points on Callisto are listed. Selected points are identified on maps of the satellites. Measurements of these points were made on 234 pictures of Io, 115 pictures of Europa, 282 pictures of Ganymede, and 200 pictures of Callisto. The systems of longitude were defined by craters on Europa, Ganymede, and Callisto. Preliminary solutions are found for the directions of the axes of rotation of the Galilean satellites. Mean radii are determined as 1815 + or - 5 km for Io, 1569 + or - 10 km for Europa, 2631 + or - km for Ganymede, and 2400 + or - 10 km for Callisto
Metastable liquid-liquid coexistence and density anomalies in a core-softened fluid
Linearly-sloped or `ramp' potentials belong to a class of core-softened
models which possess a liquid-liquid critical point (LLCP) in addition to the
usual liquid-gas critical point. Furthermore they exhibit thermodynamic
anomalies in the density and compressibility, the nature of which may be akin
to those occurring in water. Previous simulation studies of ramp potentials
have focused on just one functional form, for which the LLCP is
thermodynamically stable. In this work we construct a series of ramp
potentials, which interpolate between this previously studied form and a
ramp-based approximation to the Lennard-Jones (LJ) potential. By means of Monte
Carlo simulation, we locate the LLCP, the first order high density liquid
(HDL)-low density liquid (LDL) coexistence line, and the line of density maxima
for a selection of potentials in the series. We observe that as the LJ limit is
approached, the LLCP becomes metastable with respect to freezing into a
hexagonal close packed crystalline solid. The qualitative nature of the phase
behaviour in this regime shows a remarkable resemblance to that seen in
simulation studies of accurate water models. Specifically, the density of the
liquid phase exceeds that of the solid; the gradient of the metastable LDL-HDL
line is negative in the pressure (p)-temperature (T) plane; while the line of
density maxima in the p-T plane has a shape similar to that seen in water and
extends well into the {\em stable} liquid region of the phase diagram. As such,
our results lend weight to the `second critical point' hypothesis as an
explanation for the anomalous behaviour of water.Comment: 7 pages, 8 figure
Control networks for the Galilean satellites, November 1979
Pictures of the four Galilean satellites taken as the two Voyager spacecraft approached Jupiter during March and July 1979 are presented. Control nets of the Galilean satellites, computed photogrammetrically, and measurements of the mean radii are presented. The pictures in the control nets are identified, the coordinates of the control points are given, and identifications of some of the control points are shown on figures. The use of star field pictures to compute the focal lengths of the camera is discussed and the geometric relationship between the narrow and wide and angle cameras is reported. A description of the coordinate systems of the Galilean satellites is presented and the status of the control net computations is reported
Changes in mouse gastrointestinal microbial ecology with ingestion of kale
Kale, a cultivar of Brassica oleracea, has attracted a great deal of attention because of its health-promoting effects, which are thought to be exerted through modulation of the intestinal microbiota. The present study was performed to investigate the effects of kale ingestion on the gastrointestinal microbial ecology of mice. 21 male C57BL/6J mice were divided into three groups and housed in a specific pathogen-free facility. The animals were fed either a control diet or experimental diets supplemented with different commercial kale products for 12 weeks. Contents of the caecum and colon of the mice were processed for the determination of active bacterial populations by a bacterial rRNA-based quantification method and short-chain fatty acids by HPLC. rRNAs of Bacteroides-Prevotella, the Clostridium coccoides-Eubacterium rectale group, and Clostridium leptum subgroup constituted the major fraction of microbiota regardless of the composition of the diet. The ratio of Firmicutes to Bacteroidetes was higher in the colon samples of one of the kale diet groups than in the control. The colonic butyrate level was also higher with the kale-supplemented diet. Overall, the ingestion of kale tended to either increase or decrease the activity of specific bacterial groups in the mouse gastrointestinal tract, however, the effect might vary depending on the nutritional composition.ArticleBENEFICIAL MICROBES. 5(3):345-349 (2014)journal articl
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