14,540 research outputs found
Utilization of satellite data in mesoscale models of severe weather
The impact of the diagnostic initialization of divergence on short-range precipitation forecasts produced by a model, a numerical study of a storm, collaborative modeling and diagnostic studies, and a numerical investigation of the impact of SEASAT surface wind data used in the static initialization of the North Atlantic Storm of 9-10 September 1978 are summerized
Utilization of satellite data in mesoscale modeling of severe weather
The Visible Infrared Spin Scan Radiometer Atmospheric Sounder (VAS) data were used to model the 36 hour cyclogenesis period over the Pacific Ocean. Various combinations of VAS data, conventional radiosonde data, and gridded data from the National Weather Service global analysis were used in successive-correction and variational objective-analysis procedures. The Penn State/NCAR mesoscale model was used to test the impact of the VAS data on a 12 hour forecast of convective precipitation in the midweastern U.S
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Catecholaminergic neurons in medullary nuclei are among the post-synaptic targets of descending projections from infralimbic area 25 of the rat medial prefrontal cortex
The infralimbic (IL) 'visceromotor' area of the rat medial prefrontal cortex projects to strategic subcortical nuclei involved in autonomic functions. Central among these targets are the nucleus tractus solitarius (NTS) and the rostral ventrolateral medulla (rVLM). By combining tract-tracing using the anterograde tracer biotinylated dextran amine (BDA) with immunolabeling for tyrosine hydroxylase (TH; an enzyme marker of catecholaminergic neurons), a limited proportion of BDA-labeled IL axonal boutons in the NTS and rVLM was found to be closely associated with TH immunopositive (+) target structures. Such structural appositions were mainly located proximally over the labeled dendritic arbors of identified TH+ neurons.
Quantitative ultrastructural examination revealed that in NTS, TH+ dendritic shafts comprised 7.0% of the overall post-synaptic target population innervated by BDA-labeled IL boutons, whereas TH+ dendritic spines represented 1.25% of targets. In rVLM, TH+ shafts represented 9.0% and TH+ spines 2.5% of IL targets. Labeled IL boutons established exclusively asymmetric Gray Type 1 (presumed excitatory) synaptic junctions.
The results indicate that subpopulations of catecholaminergic neurons in the NTS and rVLM are among the spectrum of post-synaptic neurons monosynaptically innervated by descending 'excitatory' input from IL cortex. Such connectivity, albeit restricted, identifies the potential direct influence of IL cortex on the processing and distribution of cardiovascular, respiratory and related autonomic information by catecholaminergic neurons in the NTS and VLM of the rat
Electrical properties of oxide glasses containing iron and manganese
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Utilization of VAS satellite data in the initialization of an oceanic-cyclogenesis simulation
A series of experiments was performed to test various method of incorporating Visible Infrared Spin Scan Radiometer Atmospheric Sounder (VAS)-sounding data into the initial conditions of the Penn State University/National Center for Atmospheric mesoscale model. The VAS data for this ocean-cyclogenesis case consist of 110 irregularly distributed temperature and humidity soundings located over the North Pacific Ocean and apply at approximately 1200 GMT 10 November 1981. Various methods of utilizing VAS data in the initial condition of a mesoscale model were evaluated
Verification of mesoscale objective analyses of VAS and rawinsonde data using the March 1982 AVE/VAS special network data
Various combinations of VAS (Visible and Infrared Spin Scan Radiometer Atmospheric Sounder) data, conventional rawinsonde data, and gridded data from the National Weather Service's (NWS) global analysis, were used in successive-correction and variational objective-analysis procedures. Analyses are produced for 0000 GMT 7 March 1982, when the VAS sounding distribution was not greatly limited by the existence of cloud cover. The successive-correction (SC) procedure was used with VAS data alone, rawinsonde data alone, and both VAS and rawinsonde data. Variational techniques were applied in three ways. Each of these techniques was discussed
Eccentric discs in binaries with intermediate mass ratios: Superhumps in the VY Sculptoris stars
We investigate the role of the eccentric disc resonance in systems with mass
ratios q greater than 1/4, and demonstrate the effects that changes in the mass
flux from the secondary star have upon the disc radius and structure. The
addition of material with low specific angular momentum to its outer edge
restricts a disc radially. Should the mass flux from the secondary be reduced,
it is possible for the disc in a system with mass ratio as large as 1/3 to
expand to the 3:1 eccentric inner Lindblad resonance and for superhumps to be
excited.Comment: 6 pages with 7 figures, accepted by MNRA
The role of the mora in the timing of spontaneous Japanese speech
This study investigates whether the mora is used in controlling timing in Japanese speech, or is instead a structural unit in the language not involved in timing. Unlike most previous studies of mora-timing in Japanese, this article investigates timing in spontaneous speech. Predictability of word duration from number of moras is found to be much weaker than in careful speech. Furthermore, the number of moras predicts word duration only slightly better than number of segments. Syllable structure also has a significant effect on word duration. Finally, comparison of the predictability of whole words and arbitrarily truncated words shows better predictability for truncated words, which would not be possible if the truncated portion were compensating for remaining moras. The results support an accumulative model of variance with a final lengthening effect, and do not indicate the presence of any compensation related to mora-timing. It is suggested that the rhythm of Japanese derives from several factors about the structure of the language, not from durational compensation
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