420 research outputs found
TIRSPEC : TIFR Near Infrared Spectrometer and Imager
We describe the TIFR Near Infrared Spectrometer and Imager (TIRSPEC) designed
and built in collaboration with M/s. Mauna Kea Infrared LLC, Hawaii, USA, now
in operation on the side port of the 2-m Himalayan Chandra Telescope (HCT),
Hanle (Ladakh), India at an altitude of 4500 meters above mean sea level. The
TIRSPEC provides for various modes of operation which include photometry with
broad and narrow band filters, spectrometry in single order mode with long
slits of 300" length and different widths, with order sorter filters in the Y,
J, H and K bands and a grism as the dispersing element as well as a cross
dispersed mode to give a coverage of 1.0 to 2.5 microns at a resolving power R
of ~1200. The TIRSPEC uses a Teledyne 1024 x 1024 pixel Hawaii-1 PACE array
detector with a cutoff wavelength of 2.5 microns and on HCT, provides a field
of view of 307" x 307" with a plate scale of 0.3"/pixel. The TIRSPEC was
successfully commissioned in June 2013 and the subsequent characterization and
astronomical observations are presented here. The TIRSPEC has been made
available to the worldwide astronomical community for science observations from
May 2014.Comment: 20 pages, 21 figures, 2 tables. Accepted for publication in Journal
of Astronomical Instrumentatio
Impaired CD8 T cell memory and CD4 T cell primary responses in IL-7RĪ± mutant mice
Loss of interleukin (IL)-7 or the IL-7 receptor alpha (IL-7RĪ±, CD127) results in severe immunodeficiencies in mice and humans. To more precisely identify signals governing IL-7 function in vivo, we have disrupted the IL-7RĪ± Y449XXM motif in mice by knock-in mutagenesis (IL-7RĪ±449F). Thymic precursors were reduced in number in IL-7RĪ±449F mice, but in marked contrast to IL-7RĪ±ā/ā knockout mice, thymocytes and peripheral T cells developed normally. Strikingly, Listeria infection revealed that CD4 and CD8 T cells had different requirements for IL-7RĪ± signals. CD4 T cells failed to mount a primary response, but despite normal CD8 primary responses, maintenance of CD8 memory was impaired in IL-7RĪ±449F mice. Furthermore, we show that Bcl-2 is IL-7RĪ± Y449 independent and insufficient for IL-7āmediated maintenance of CD8 memory
Effects of cooking methods and in-vitro digestion on the digestibility and antioxidant properties of ngari (a fermented fish product of India)
879-888Ngari is a popular ethnic fermented fish product from North-Eastern India. It is consumed after heat process either as a part of regular meal or as a condiment. However, there is no adequate knowledge on the digestion of ngari and the bioactive potential of the digest. The present study was aimed to evaluate the effect of different heat processes viz., air frying, roasting and sautéing on the chemical attributes and in-vitro digestion characteristics of ngari with reference to digestibility and antioxidant potential. The different heat processes significantly increased the dry matter content, thereby altering the proximate composition of the ngari. Nutritional analyses revealed that the highest value of protein is in air fried ngari (44.14%), while maximum fat in sautéed ngari (27.57%). Fatty acids analysis showed that palmitic, oleic and linoleic acid were the major fatty acids present in ngari irrespective of different heat processing. Antioxidant potential of ngari was significantly influenced by heating processes and digestion methods (pepsin or pepsin-cum-pancreatin). Heat processes significantly reduced DPPH (2,2-diphenyl-1-picrylhydrazyl) and metal chelating activity, while increasing the reducing power of the nagri. Study on peptide released during digestion by SDS-PAGE (Sodium lauryl sulphate-polyacrylamide gel electrophoresis) showed that pepsin digestion led to formation of low molecular weight peptides (14-66 kDa). Subsequently, the pepsin-cum-pancreatin digestion degraded the relatively larger peptides into further smaller ones. The different heat processes enhanced the sensory appeal of the product without exerting any negative influence on its digestibility and bioactive properties
Effects of Cooking Methods and in-vitro Digestion on the Digestibility and Antioxidant Properties of Ngari (a fermented fish product of India)
Ngari is a popular ethnic fermented fish product from North-Eastern India. It is consumed after heat process either as a part of regular meal or as a condiment. However, there is no adequate knowledge on the digestion of Ngari and the bioactive potential of the digest. The present study was aimed to evaluate the effect of different heat processes viz., air frying, roasting and sautƩing-on the chemical attributes and in-vitro digestion characteristics of Ngari with reference to digestibility and antioxidant potential. The different heat processes significantly increased the dry matter content, thereby altering the proximate composition of the Ngari. Nutritional analyses revealed that highest value of protein is in air fried Ngari (44.14%), while maximum fat in sautƩed Ngari (27.57%). Fatty acids analysis showed that palmitic, oleic and linoleic acid were the major fatty acids present in Ngari irrespective of different heat processing. Antioxidant potential of Ngari was significantly influenced by heating processes and digestion methods (pepsin or pepsin-cum-pancreatin). Heat processes significantly reduced DPPH (2,2-diphenyl-1-picrylhydrazyl) and metal chelating activity, while increasing the reducing power of the Nagri. Study of peptide released during digestion by SDS-PAGE (Sodium lauryl sulphate-polyacrylamide gel electrophoresis) showed that pepsin digestion led to formation of low molecular weight peptides (14-66 kDa). Subsequently, the pepsin-cum-pancreatin digestion disintegrated the relatively larger peptides into further smaller ones. The different heat processes enhanced the sensory appeal of the product without exerting any negative influence on its digestibility and bioactive properties
Following the TraCS of exoplanets with Pan-Planets: Wendelstein-1b and Wendelstein-2b
Hot Jupiters seem to get rarer with decreasing stellar mass. The goal of the Pan-Planets transit survey was the detection of such planets and a statistical characterization of their frequency. Here, we announce the discovery and validation of two planets found in that survey, Wendelstein-1b and Wendelstein-2b, which are two short-period hot Jupiters that orbit late K host stars. We validated them both by the traditional method of radial velocity measurements with the HIgh Resolution Echelle Spectrometer and the Habitable-zone Planet Finder instruments and then by their Transit Color Signature (TraCS). We observed the targets in the wavelength range of 4000ā24 000 ā« and performed a simultaneous multiband transit fit and additionally determined their thermal emission via secondary eclipse observations. Wendelstein-1b is a hot Jupiter with a radius of 1.0314_(ā0.0061)^(+0.0061) R_J and mass of 0.592_(ā0.129)^(+0.0165) M_J, orbiting a K7V dwarf star at a period of 2.66 d, and has an estimated surface temperature of about 1727āāāāŗā·āø K. Wendelstein-2b is a hot Jupiter with a radius of 1.1592_(ā0.0210)^(+0.0204) R_J and a mass of 0.731_(ā0.311)^(+0.0541) M_J, orbiting a K6V dwarf star at a period of 1.75 d, and has an estimated surface temperature of about 1852āāāāāŗĀ¹Ā²ā° K. With this, we demonstrate that multiband photometry is an effective way of validating transiting exoplanets, in particular for fainter targets since radial velocity follow-up becomes more and more costly for those targets
Automated Galaxy Morphology: A Fourier Approach
We use automated surface photometry and pattern classification techniques to
morphologically classify galaxies. The two-dimensional light distribution of a
galaxy is reconstructed using Fourier series fits to azimuthal profiles
computed in concentric elliptical annuli centered on the galaxy. Both the phase
and amplitude of each Fourier component have been studied as a function of
radial bin number for a large collection of galaxy images using principal
component analysis. We find that up to 90 percent of the variance in many of
these Fourier profiles may be characterized in as few as 3 principal components
and their use substantially reduces the dimensionality of the classification
problem. We use supervised learning methods in the form of artificial neural
networks to train galaxy classifiers that detect morphological bars at the
85-90 percent confidence level and can identify the Hubble type with a 1-sigma
scatter of 1.5 steps on the 16-step stage axis of the revised Hubble system.
Finally, we systematically characterize the adverse effects of decreasing
resolution and S/N on the quality of morphological information predicted by
these classifiers.Comment: Accepted to Astrophysical Journal, 43 pages, 12 figure
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