9,343 research outputs found
Petrologic constraints on the pressure, temperature, time and composition of the Martian interior
Petrologic analysis of surface samples has been used to deduce pressure and temperature conditions existing in the crust and upper mantle at specific times in the Earth's history, as well as to estimate the chemical and mineralogical composition of the crust and upper mantle. The same techniques can be applied to samples of the Martian surface to provide P, T, time and composition constraints of the Martian interior. Estimates of P and T conditions existing at a given time would, in turn, provide strong constraints on the thermal evolution of Mars. Knowledge of the chemical and mineralogical composition of the Martian interior is of fundamental importance in assessing the early history of the solar system. A general petrological approach is outlined, describing the kinds of sample required, summarizing current understanding of the Martian interior based on experimental petrology, and outlining some of the important experiments needed to allow a full petrologic interpretation of Martian samples
Word-decoding as a function of temporal processing in the visual system.
This study explored the relation between visual processing and word-decoding ability in a normal reading population. Forty participants were recruited at Arizona State University. Flicker fusion thresholds were assessed with an optical chopper using the method of limits by a 1-deg diameter green (543 nm) test field. Word decoding was measured using reading-word and nonsense-word decoding tests. A non-linguistic decoding measure was obtained using a computer program that consisted of Landolt C targets randomly presented in four cardinal orientations, at 3-radial distances from a focus point, for eight compass points, in a circular pattern. Participants responded by pressing the arrow key on the keyboard that matched the direction the target was facing. The results show a strong correlation between critical flicker fusion thresholds and scores on the reading-word, nonsense-word, and non-linguistic decoding measures. The data suggests that the functional elements of the visual system involved with temporal modulation and spatial processing may affect the ease with which people read
A strong performance by District community banks in 1998
Community banks in Tenth District states had another good year in 1998. They continued to benefit from solid growth in the district economy. And in contrast to some large banks in other parts of the country, they were largely unaffected by the turmoil in financial markets in the latter part of the year. To be sure, average profitability would have edged down in 1998 were it not for the decision by a substantial number of banks to change their tax status. Even accounting for this effect, however, district community banks remained highly profitable. ; Furthermore, overall loan quality showed no sign of deterioration, and loan growth and deposit growth were both healthy. Community banks in the district also compared favorably with their peers in the rest of the nation in all performance measures.Banks and banking ; Federal Reserve District, 10th
Aedes Minervae in Foro Boario.
In this article the Autor advances a new interpretation for the archaic temple discovered beneath the twin shrines of Fortuna and Mater Matuta in the Forum Boarium. Analysing Colini’s (the excavator’s) interpretation by which this temple is assumed to be a temple of Mater Matuta, he shows us how this assumption is based in scanty and indirect evidence. Even so, it is accepted by specialists as a real dogma. Comparing the statuary group connected with the second phase of the archaic temple with a recently restored terracotta statue group from Portonaccio Sanctuary at Veii, the Autor arrives at a very different conclusion. As a matter of fact, he is able to demonstrate that this archaic temple in Forum Boarium is in reality an “Aedes Minervae” and not Mater M atuta’s temple as is usually assumed
Establishing confidence in CCV/ACT technology
Despite significant advancements in controls configured vehicles/active controls technology (CCV/ACT) in the past decade, few applications of this promising technology have appeared in recent aircraft designs. The status of CCV/ACT is summarized, and some of the constraints which are retarding its wider application are described. Suggestions toward establishing an increased level of confidence in the technology are given
Geopotential models in the Australian region
The ability of three high-order geopotential models (OSU81, GPM2 and OSU86E) to recover the gravity anomaly field (delta g) in the Australian region was tested. The region was divided into 2 x 2 deg blocks, and the mean and rms of the residual gravity (delta g measured - delta g modeled) was found to estimate the fit of the model to the point gravity data. The results showed that OSU81 and GPM2 performed similarly, recovering the delta g with a mean value of less than plus or minus 5 mGal in 63 and 70 percent of the blocks, respectively. However, both these models achieved a fit of worse that was plus or minus 13 mGal in 6 to 7 percent of cases. These were in areas either on or near the coast, or in the Central Australian region, inferring that for a precise geoid slope determination in these regions, a detailed analysis of delta g in region is needed. On the other hand, OSU86E produced a very good result, having a mean fit of less than plus or minus 5 mGal in 80 percent of the blocks, and worse than plus or minus 13 mGal in only 1 percent of cases. The rms values for this model were also improved over the other two models, indicating that for applications requiring highest precision, the preferred model is OSU86E
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