896 research outputs found
Development and testing of an image tube camera and spectrograph Final report
Image tube camera and spectrograph for observing artificial auror
Development and testing of an image tube camera and spectrograph Quarterly progress report, period ending 31 Mar. 1969
Electron beam field mapping with aid of image tube cameras and spectrometer
V4332 Sagittarii revisited
The eruption of V4332 Sgr discovered in February 1994 shows striking
similarities to that of V838 Mon started in January 2002. The nature of these
eruptions is, however, enigmatic and unclear. We present new photometric and
spectroscopic data on V4332 Sgr obtained in April-May 2003 at the SAAO. The
obtained spectrum shows an unusual emission-line component superimposed on an
early M-type stellar spectrum. The emission-line spectrum is of very low
excitation and is dominated by lines from neutral elemets (NaI, FeI, CaI) and
molecular bands (TiO, ScO, AlO). We also analyse all the observational data,
mainly photometric measurements, available for V4332 Sgr. This allows us to
follow the evolution of the effective temperature, radius and luminosity of the
object since February 1994 till 2003. We show that the observed decline of
V4332 Sgr can be accounted for by a gravitational contraction of an inflated
stellar envelope. The combined optical and infrared photometry in 2003 shows
that apart from the M-type stellar component there is a strong infrared excess
in the KLM bands. This excess was absent in the 2MASS measurements done in 1998
but was probably starting to appear in K in 1999 when the object was observed
in the DENIS survey. We interpret the results in terms of a stellar merger
scenario proposed by Soker & Tylenda. The infrared excess is likely to be due
to a disc-like structure which is either of protostellar nature or has been
produced during the 1994 eruption and stores angular momentum from the merger
event.Comment: 11 pages, 5 figures, accepted in Astronomy & Astrophysic
Comparison of multiple methods for identification of hyperprolactinemia in the presence of macroprolactin
Macroprolactin is a large, heterogeneous form of prolactin with limited bioavailability. Detection of macroprolactin by different immunoassays varies widely. The objectives of this study were to determine the immunoreactivity of macroprolactin by the Ortho Clinical Diagnostics Vitros ECi prolactin immunoassay, establish the most effective method for interpreting the prolactin concentration after PEG-precipitation, and correlate the clinical features of hyperprolactinemia with the presence of macroprolactin
Far infrared mapping of three Galactic star forming regions : W3(OH), S 209 & S 187
Three Galactic star forming regions associated with W3(OH), S209 and S187
have been simultaneously mapped in two trans-IRAS far infrared (FIR) bands
centered at ~ 140 and 200 micron using the TIFR 100 cm balloon borne FIR
telescope. These maps show extended FIR emission with structures. The HIRES
processed IRAS maps of these regions at 12, 25, 60 & 100 micron have also been
presented for comparison. Point-like sources have been extracted from the
longest waveband TIFR maps and searched for associations in the other five
bands. The diffuse emission from these regions have been quantified, which
turns out to be a significant fraction of the total emission. The spatial
distribution of cold dust (T < 30 K) for two of these sources (W3(OH) & S209),
has been determined reliably from the maps in TIFR bands. The dust temperature
and optical depth maps show complex morphology. In general the dust around S209
has been found to be warmer than that in W3(OH) region.Comment: Accepted for publication in Journal of Astrophysics and Astronomy (20
pages including 8 figures & 3 tables
An excess of emission in the dark cloud LDN 1111 with the Arcminute Microkelvin Imager
We present observations of the Lynds' dark nebula LDN 1111 made at microwave
frequencies between 14.6 and 17.2 GHz with the Arcminute Microkelvin Imager
(AMI). We find emission in this frequency band in excess of a thermal
free--free spectrum extrapolated from data at 1.4 GHz with matched uv-coverage.
This excess is > 15 sigma above the predicted emission. We fit the measured
spectrum using the spinning dust model of Drain & Lazarian (1998a) and find the
best fitting model parameters agree well with those derived from Scuba data for
this object by Visser et al. (2001).Comment: accepted MNRA
Concentrations of Pro-Inflammatory Cytokines Are Not Associated with Senescence Marker p16INK4a or Predictive of Intracellular Emtricitabine/Tenofovir Metabolite and Endogenous Nucleotide Exposures in Adults with HIV Infection
As the HIV-infected population ages, the role of cellular senescence and inflammation on co-morbid conditions and pharmacotherapy is increasingly of interest. p16INK4a expression, a marker for aging and senescence in T-cells, is associated with lower intracellular concentrations of endogenous nucleotides (EN) and nucleos(t)ide reverse transcriptase inhibitors (NRTIs). This study expands on these findings by determining whether inflammation is contributing to the association of p16INK4a expression with intracellular metabolite (IM) exposure and endogenous nucleotide concentrations
Cdkn2a Is an Atherosclerosis Modifier Locus That Regulates Monocyte/Macrophage Proliferation
Common genetic variants in a 58-kilobase region of chr 9p21, near the CDKN2A/CDKN2B tumor suppressor locus, are strongly associated with coronary artery disease. However, the underlying mechanism of action remains unknown
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