919 research outputs found
Length-weight relationship of a hill-stream fish, Glyptothorax telchitta (Ham.) from Saptakoshi River of Nepal
The length-weight relationship of a hill-stream fish, Glyptothorax telchitta from Saptakoshi River of Nepal was analysed using the formula W=aLᵇ. The exponential values computed for total length and standard length in relation to body weight were 2.991 and 2.888 respectively
Effect of benzocaine on opercular movement and oxygen consumption in Channa punctatus (Bloch)
Effect of anaesthetization with benzocaine at the rate of 18.0 mg.1super(-1) on juveniles of Channa punctatus was observed using a cylindrical glass respirometer. Oxygen consumption and opercular movement were studied at 3h and 24h of anaesthetization. The oxygen consumption of control fish increased linearly from 0.183±0.029 to 0.481±0.034 mlO sub(2).h super(-1) with an increase in body weight from 1.45±0.18 to 6.12±0.11g and showed a reduction (p<0.001) of about 41% in 3h and 37% in 24h anaesthetization of Benzocaine. Similarly, the opercular movement of control fish ranging between 46±1 to 49±1min super(-1) came down to show a reduction (p<0.001) of 43% and 38% respectively in 3h and 24h anaesthetization. The information is useful in calculation of oxygen requirement of this species for live transportation and other experimental purpose
Evidence of microscopic effects in fragment mass distribution in heavy ion induced fusion-fission reactions
Our measurements of variances () in mass distributions of
fission fragments from fusion-fission reactions of light projectiles (C, O and
F) on deformed thorium targets exhibit a sharp anomalous increase with energy
near the Coulomb barrier, in contrast to the smooth variation of
for the spherical bismuth target. This departure from expectation based on a
statistical description is explained in terms of microscopic effects arising
from the orientational dependence in the case of deformed thorium targets.Comment: Replaced with revised version, to appear in Phys. Lett.
Correlations in Intermediate Energy Two-Proton Removal Reactions
We report final-state-exclusive measurements of the light charged fragments in coincidence with Ne26 residual nuclei following the direct two-proton removal from a neutron-rich Mg28 secondary beam. A Dalitz-plot analysis and comparisons with simulations show that a majority of the triple-coincidence events with two protons display phase-space correlations consistent with the (two-body) kinematics of a spatially correlated pair-removal mechanism. The fraction of such correlated events, 56(12)%, is consistent with the fraction of the calculated cross section, 64%, arising from spin S=0 two-proton configurations in the entrance-channel (shell-model) Mg28 ground state wave function. This result promises access to an additional and more specific probe of the spin and spatial correlations of valence nucleon pairs in exotic nuclei produced as fast secondary beams. � 2012 American Physical Society
A Honeycomb Proportional Counter for Photon Multiplicity Measurement in the ALICE Experiment
A honeycomb detector consisting of a matrix of 96 closely packed hexagonal
cells, each working as a proportional counter with a wire readout, was
fabricated and tested at the CERN PS. The cell depth and the radial dimensions
of the cell were small, in the range of 5-10 mm. The appropriate cell design
was arrived at using GARFIELD simulations. Two geometries are described
illustrating the effect of field shaping. The charged particle detection
efficiency and the preshower characteristics have been studied using pion and
electron beams. Average charged particle detection efficiency was found to be
98%, which is almost uniform within the cell volume and also within the array.
The preshower data show that the transverse size of the shower is in close
agreement with the results of simulations for a range of energies and converter
thicknesses.Comment: To be published in NIM
The effect of layer number and substrate on the stability of graphene under MeV proton beam irradiation
The use of graphene electronics in space will depend on the radiation
hardness of graphene. The damage threshold of graphene samples, subjected to 2
MeV proton irradiation, was found to increase with layer number and also when
the graphene layer was supported by a substrate. The thermal properties of
graphene as a function of the number of layers or as influenced by the
substrate argue against a thermal model for the production of damage by the ion
beam. We propose a model of intense electronically-stimulated surface
desorption of the atoms as the most likely process for this damage mechanism.Comment: 20 pages, 5 figure
STUDIES ON INCIDENCE AND ANTIBIOGRAM OF SALMONELLA SEROVARS ISOLATED FROM RAW PORK IN AIZAWL AND IMPHAL, INDIA
The study was conducted to determine the incidence, serotypes and antimicrobial resistance profile of
Salmonella serovars isolated from raw pork of Aizawl and Imphal, India. A total of 200 raw pork samples (100 from
Aizawl and Imphal each) were collected from unorganized butcher shops and subjected for isolation and identification of
Salmonella spp. which phenotypically detected 5 Salmonella isolates. The Salmonella isolates were further confirmed
genotypically by 16S rRNA genus specific PCR and recorded the incidence rate of 2.50%. Serotyping of the isolates
revealed that all the three isolates from Imphal were Salmonella enterica serovar Virchow whereas the two isolates of
Aizawl were Salmonella enterica serovar Virchow and Salmonella enterica serovar Typhimurium, one each. The
antimicrobial sensitivity profile against 16 antimicrobials revealed that amikacin, imipenem, ofloxacine, norfloxacin and
ciprofloxacin were 100% sensitive and among the resistant antimicrobials, highest resistance was recorded against
ceftriaxone (80.00%) followed by amoxyclav and cotrimoxazole (60.00% each). Presence of Salmonella Typhimurium
from raw pork is a matter of concern from hygiene and sanitation. Moreover, the antimicrobial resistance profile showed
increasing resistance against cephalosporin, amino-penicillin and amino glycosides
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
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