72,717 research outputs found
Are you a researcher as well as a medical illustrator?
When we list the areas of practice for medical illustrators we always include research, but how involved in research are we? The aim of this activity is to encourage your professional development not just as a medical illustrator but your involvement with research whether that is undertaking your own research, undertaking evidence based practice (1) , working as part of a research team, advising researchers on the value of medical illustration or supporting a student undertaking a research project for their degree or post-graduate qualification
Drag coefficients for partially inflated flat circular parachutes
Free-body tests of flat circular parachutes and determination of aerodynamic drag coefficients during partial inflatio
The Molecular Gas Distribution and Schmidt Law in M33
The relationship between the star formation rate and surface density of
neutral gas within the disk of M33 is examined with new imaging observations of
CO J=1-0 emission gathered with the FCRAO 14m telescope and IRAS HiRes images
of the 60 micron and 100 micron emission. The Schmidt law, Sigma_SFR ~
Sigma_gas^n, is constructed using radial profiles of the HI 21cm, CO, and far
infrared emission. A strong correlation is identified between the star
formation rate and molecular gas surface density. This suggests that the
condensation of giant molecular clouds is the limiting step to star formation
within the M33 disk. The corresponding molecular Schmidt index, n_{mol}, is
1.36 +/- 0.08. The star formation rate has a steep dependence on total mass gas
surface density, (Sigma_{HI}+Sigma_{H_2}), owing to the shallow radial profile
of the atomic gas which dominates the total gas surface density for most radii.
The disk pressure of the gas is shown to play a prominent role in regulating
the molecular gas fraction in M33.Comment: 19 pages + 5 figures. Accepted for publication in Ap
Regulation of acetylcholine release from guinea-pig bladder urothelial cells - potential role in bladder filling sensations
Hawking temperature from scattering off the charged 2D black hole
The charged 2D black hole is visualized as presenting an potential barrier
to on-coming tachyon wave. Since this takes the complicated
form, an approximate form is used for scattering analysis. We
calculate the reflection and transmission coefficients for scattering of
tachyon off the charged 2D black hole. The Hawking temperature is also derived
from the reflection coefficient by Bogoliubov transformation. In the limit of
, we recover the Hawking temperature of the 2D dilaton black hole.Comment: 12 pages 3 figures, RevTeX, to obtain figures contact author
([email protected]
Mapping of RNA- temperature-sensitive mutants of Sindbis virus: assignment of complementation groups A, B, and G to nonstructural proteins
Four complementation groups of temperature-sensitive (ts) mutants of Sindbis virus that fail to make RNA at the nonpermissive temperature are known, and we have previously shown that group F mutants have defects in nsP4. Here we map representatives of groups A, B, and G. Restriction fragments from a full-length clone of Sindbis virus, Toto1101, were replaced with the corresponding fragments from the various mutants. These hybrid plasmids were transcribed in vitro by SP6 RNA polymerase to produce infectious RNA transcripts, and the virus recovered was tested for temperature sensitivity. After each lesion was mapped to a specific region, cDNA clones of both mutants and revertants were sequenced in order to determine the precise nucleotide change responsible for each mutation. Synthesis of viral RNA and complementation by rescued mutants were also examined in order to study the phenotype of each mutation in a uniform genetic background. The single mutant of group B, ts11, had a defect in nsP1 (Ala-348 to Thr). All of the group A and group G mutants examined had lesions in nsP2 (Ala-517 to Thr in ts17, Cys-304 to Tyr in ts21, and Gly-736 to Ser in ts24 for three group A mutants, and Phe-509 to Leu in ts18 and Asp-522 to Asn in ts7 for two group G mutants). In addition, ts7 had a change in nsP3 (Phe-312 to Ser) which also rendered the virus temperature sensitive and RNA-. Thus, changes in any of the four nonstructural proteins can lead to failure to synthesize RNA at a nonpermissive temperature, indicating that all four are involved in RNA synthesis. From the results presented here and from previous results, several of the activities of the nonstructural proteins can be deduced. It appears that nsP1 may be involved in the initiation of minus-strand RNA synthesis. nsP2 appears to be involved in the initiation of 26S RNA synthesis, and in addition it appears to be a protease that cleaves the nonstructural polyprotein precursors. It may also be involved in shutoff of minus-strand RNA synthesis. nsP4 appears to function as the viral polymerase or elongation factor. The functions of nsP3 are as yet unresolved
A new nickel-base wrought superalloy for applications up to 1033 K (1400 F)
Alloy was melted from high purity raw materials and cast ingots extruded at 1422 K. Material was hot rolled to 0.013 m diameter bar stock. Partial solution heat-treatment followed by aging produced structure of fine gamma prime precipitate reinforcing gamma matrix containing coarser blocky gamma prime particles. Alloy can be processed by powder metallurgy
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