626 research outputs found
Arsenic induced hematological and biochemical responses in nutritionally important catfish Clarias batrachus (L.)
AbstractThe impact of sublethal toxicity of sodium arsenite on hematological and certain biochemical parameters of the fresh water catfish Clarias batrachus has been analyzed following exposure of sublethal concentration (1mg/L; 5% of LC50 value) of sodium arsenite for 10, 30, 45, and 60 days. Arsenic bioaccumulation in the blood tissue of the fish increased progressively with increased period of exposure. The values of total erythrocyte count (TECs), total leucocytes count (TLCs), hemoglobin concentration, and packed cell volume (PCV) 1.40±0.03×106/mm3, 174.83±2.74×103/mm3, 5.01±0.26g/100ml, 25.00±1.06 were observed respectively at the end of 60 days of exposure. The results of hematological indices were found to be 179.23±8.81fl/cell for mean corpuscular volume (MCV), 35.92±1.89pg/cell for mean corpuscular hemoglobin (MCH) and 20.17±1.12g/dl for mean corpuscular hemoglobin concentration (MCHC). The present findings are clearly indicating severe fish anemia due to the arsenic salt exposure. The continued arsenic toxicity results in decreased serum protein concentration that might be a cause for the loss of weight as well as weakness in the fish
Advantage of BIOX tank technology over aeration tank in secondary biological treatment
Advantage of BIOX tank technology over aeration tank in secondary biological treatmen
LAMBDA: Large Area Modular BaF2 Detector Array for the measurement of high energy gamma rays
A large BaF2 detector array along with its dedicated CAMAC electronics and
VME based data acquisition system has been designed, constructed and installed
successfully at VECC, Kolkata for studying high energy gamma rays (E>8 MeV).
The array consists of 162 detector elements. The detectors were fabricated from
bare barium fluoride crystals (each measuring 35 cm in length and having
cross-sectional area of 3.5 cm X 3.5 cm X 35.0 cm). The basic properties of the
detectors (energy resolution, time resolution, efficiency, uniformity, fast to
slow ratio etc.) were studied exhaustively. Complete GEANT3 monte carlo
simulations were performed to optimize the detector design and also to generate
the response function. The detector system has been used successfully to
measure high energy photons from 113Sb, formed by bombarding 145 and 160 MeV
20Ne beams on a 93Nb target. The measured experimental spectra are in good
agreement with those from a modified version of the statistical model code
CASCADE. In this paper, we present the complete description of this detector
array along with its in-beam performance.Comment: 18 pages, 14 figures, accepted in NIM
Observation of multiple doubly degenerate bands in ¹⁹⁵Tl
The High-spin states in 195 Tl, populated through the 185,187 Re( 13 C, xn) fusion evaporation reaction at the beam energy of 75 MeV, were studied using the Indian National Gamma Array (INGA). More than 50 new γ transitions have been placed in the proposed level scheme which is extended up to the excitation energy of ≈ 5.6 MeV and spin =22.5ħ . Two pairs of degenerate bands based on two different quasi-particle configurations have been identified in this nucleus indicating the first observation of such bands in an odd- A nucleus in A∼190 region and signify the first evidence of multiple chiral bands in a nucleus in this region. The total Routhian surface calculations predict triaxial shapes for both the configurations and thereby, support the experimental observation. The importance of multiple neutron holes in the i13/2 orbital and the stability of shapes for these two configurations have been discussed.Financial support of Department of Science
& Technology, Govt. of India for clover detectors of INGA (Grant
No. IR/S2/PF-03/2003-II) is greatfully acknowledged. One of the
authors (S. Bhattacharya) acknowledges with thanks the financial
support received as Raja Ramanna Fellowship from the Department
of Atomic Energy, Govt. of India. T.R and Md. A.A acknowledge with
thanks the financial support received as research fellows from the
Department of Atomic Energy (DAE), Govt. of India
Thermodynamics of Gauss-Bonnet black holes revisited
We investigate the Gauss-Bonnet black hole in five dimensional anti-de Sitter
spacetimes (GBAdS). We analyze all thermodynamic quantities of the GBAdS, which
is characterized by the Gauss-Bonnet coupling and mass , comparing with
those of the Born-Infeld-AdS (BIAdS), Reissner-Norstr\"om-AdS black holes
(RNAdS), Schwarzschild-AdS (SAdS), and BTZ black holes. For we cannot
obtain the black hole with positively definite thermodynamic quantities of
mass, temperature, and entropy because the entropy does not satisfy the
area-law. On the other hand, for , we find the BIAdS-like black hole,
showing that the coupling plays the role of pseudo-charge. Importantly, we
could not obtain the SAdS in the limits of , which means that the GBAdS
is basically different from the SAdS. In addition, we clarify the connections
between thermodynamic and dynamical stability. Finally, we also conjecture that
if a black hole is big and thus globally stable, its quasinormal modes may take
analytic expressions.Comment: 22 pages, 8 figures, version to appear in EPJ
Origins of the Ambient Solar Wind: Implications for Space Weather
The Sun's outer atmosphere is heated to temperatures of millions of degrees,
and solar plasma flows out into interplanetary space at supersonic speeds. This
paper reviews our current understanding of these interrelated problems: coronal
heating and the acceleration of the ambient solar wind. We also discuss where
the community stands in its ability to forecast how variations in the solar
wind (i.e., fast and slow wind streams) impact the Earth. Although the last few
decades have seen significant progress in observations and modeling, we still
do not have a complete understanding of the relevant physical processes, nor do
we have a quantitatively precise census of which coronal structures contribute
to specific types of solar wind. Fast streams are known to be connected to the
central regions of large coronal holes. Slow streams, however, appear to come
from a wide range of sources, including streamers, pseudostreamers, coronal
loops, active regions, and coronal hole boundaries. Complicating our
understanding even more is the fact that processes such as turbulence,
stream-stream interactions, and Coulomb collisions can make it difficult to
unambiguously map a parcel measured at 1 AU back down to its coronal source. We
also review recent progress -- in theoretical modeling, observational data
analysis, and forecasting techniques that sit at the interface between data and
theory -- that gives us hope that the above problems are indeed solvable.Comment: Accepted for publication in Space Science Reviews. Special issue
connected with a 2016 ISSI workshop on "The Scientific Foundations of Space
Weather." 44 pages, 9 figure
Single Spin Asymmetry in Polarized Proton-Proton Elastic Scattering at GeV
We report a high precision measurement of the transverse single spin
asymmetry at the center of mass energy GeV in elastic
proton-proton scattering by the STAR experiment at RHIC. The was measured
in the four-momentum transfer squared range \GeVcSq, the region of a significant interference between the
electromagnetic and hadronic scattering amplitudes. The measured values of
and its -dependence are consistent with a vanishing hadronic spin-flip
amplitude, thus providing strong constraints on the ratio of the single
spin-flip to the non-flip amplitudes. Since the hadronic amplitude is dominated
by the Pomeron amplitude at this , we conclude that this measurement
addresses the question about the presence of a hadronic spin flip due to the
Pomeron exchange in polarized proton-proton elastic scattering.Comment: 12 pages, 6 figure
Search for displaced vertices arising from decays of new heavy particles in 7 TeV pp collisions at ATLAS
We present the results of a search for new, heavy particles that decay at a
significant distance from their production point into a final state containing
charged hadrons in association with a high-momentum muon. The search is
conducted in a pp-collision data sample with a center-of-mass energy of 7 TeV
and an integrated luminosity of 33 pb^-1 collected in 2010 by the ATLAS
detector operating at the Large Hadron Collider. Production of such particles
is expected in various scenarios of physics beyond the standard model. We
observe no signal and place limits on the production cross-section of
supersymmetric particles in an R-parity-violating scenario as a function of the
neutralino lifetime. Limits are presented for different squark and neutralino
masses, enabling extension of the limits to a variety of other models.Comment: 8 pages plus author list (20 pages total), 8 figures, 1 table, final
version to appear in Physics Letters
- …