2,935 research outputs found
Multiparametric and coloured extensions of the quantum group and the Yangian algebra through a symmetry transformation of the Yang-Baxter equation
Inspired by Reshetikhin's twisting procedure to obtain multiparametric
extensions of a Hopf algebra, a general `symmetry transformation' of the
`particle conserving' -matrix is found such that the resulting
multiparametric -matrix, with a spectral parameter as well as a colour
parameter, is also a solution of the Yang-Baxter equation (YBE). The
corresponding transformation of the quantum YBE reveals a new relation between
the associated quantized algebra and its multiparametric deformation. As
applications of this general relation to some particular cases, multiparametric
and coloured extensions of the quantum group and the Yangian algebra
are investigated and their explicit realizations are also discussed.
Possible interesting physical applications of such extended Yangian algebras
are indicated.Comment: 21 pages, LaTeX (twice). Interesting physical applications of the
work are indicated. To appear in Int. J. Mod. Phys.
Reaching Community Through School Going Children for Sickle Cell Disease in Zankhvav Village of Surat District, Western India
Objectives: The objective of the study was to explore a method to reach the community via school going adolescents for screening tribal people for Sickle Cell disease. Methodology: A cross-sectional study was conducted in a total of 1023 school going adolescents for Sickle Cell Disease screening by Dithionite Tube Turbidity (DTT) test with subsequent Hemoglobin Electrophoresis for confirmation among those testing positive for DTT. They were then advised to get their family members tested for the same. Results: 24.41% of school going adolescents tested positive by DTT test. 152 family members of those positive school children came forward for testing. On performing the DTT test on the family members, 53.94% tested positive. Out of those who tested positive, 61% belonged to Vasava caste; 36.6% belonged to Chaudhari caste followed by Gamit and Dhodhia Patel. On the subsequent Hemoglobin electrophoresis, 52.63% of the family members were found to be positive for Sickle Cell Trait and 1.97% tested positive for Sickle Cell Disease. Conclusions: School going children can be an effective medium to approach the community for the screening of Sickle Cell Disease
Detection of the high energy cut-off from the Seyfert 1.5 galaxy NGC 5273
We perform the NuSTAR and Swift/XRT joint energy spectral fitting of
simultaneous observations from the broad-line Seyfert 1.5 galaxy NGC 5273. When
fitted with the combination of an exponential cut-off power-law and a
reflection model, a high energy cut-off is detected at 143 keV
with 2-sigma significance. Existence of such cut-off is also consistent with
the observed Comptonizing electron temperature when fitted with a
Comptonization model independently. We observe a moderate hard X-ray
variability of the source over the time-scale of ~12 years using INTEGRAL/ISGRI
observations in the energy range of 20-100 keV. When the hard band count rate
(6-20 keV) is plotted against the soft band count rate (3-6 keV), a hard offset
is observed. Our results indicate that the cut-off energy may not correlate
with the coronal X-ray luminosity in a simple manner. Similarities in
parameters that describe coronal properties indicate that the coronal structure
of NGC 5273 may be similar to that of the broad-line radio galaxy 3C 390.3 and
another galaxy MCG-5-23-16 where the coronal plasma is dominated by electrons,
rather than electron-positron pairs. Therefore, the coronal cooling is equally
efficient to the heating mechanism keeping the cut-off energy at low even at
the low accretion rate.Comment: 11 pages, 6 figures, 1 table, accepted for publication in MNRA
Accretion disc-corona and jet emission from the radio-loud narrow-line Seyfert 1 galaxy RX J1633.3+4719
We perform X-ray/ultraviolet (UV) spectral and X-ray variability studies of
the radio-loud narrow-line Seyfert 1 (NLS1) galaxy RX J1633.3+4719 using
XMM-Newton and Suzaku observations from 2011 and 2012. The 0.3-10 keV spectra
consist of an ultrasoft component described by an accretion disc blackbody
(kT_in = 39.6^{+11.2}_{-5.5} eV) and a power law due to the thermal
Comptonization ({\Gamma} = 1.96^{+0.24}_{-0.31}) of the disc emission. The disc
temperature inferred from the soft excess is at least a factor of 2 lower than
that found for the canonical soft excess emission from radio-quiet NLS1s. The
UV spectrum is described by a power law with photon index 3.05^{+0.56}_{-0.33}.
The observed UV emission is too strong to arise from the accretion disc or the
host galaxy, but can be attributed to a jet. The X-ray emission from RX
J1633.3+4719 is variable with fractional variability amplitude =13.5 per cent. In contrast to radio-quiet active galactic nuclei
(AGN), X-ray emission from the source becomes harder with increasing flux. The
fractional rms variability increases with energy and the rms spectrum is well
described by a constant disc component and a variable power-law continuum with
the normalization and photon index being anticorrelated. Such spectral
variability cannot be caused by variations in the absorption and must be
intrinsic to the hot corona. Our finding of possible evidence for emission from
the inner accretion disc, jet and hot corona from RX J1633.3+4719 in the
optical to X-ray bands makes this object an ideal target to probe the disc-jet
connection in AGN.Comment: 12 pages, 11 figures, 3 tables, Published in MNRA
Morphogen-induced platelet activation and cell signalling
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