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Ab initio investigation on the reaction mechanism of ClO + O --> Cl + O2 reaction has been performed using correlation consistent triple zeta basis set. The geometry and frequency of the reactants, products, minimum energy geometries and transition states are obtained using MP2 method and energetics are obtained at the QCISD(T)//MP2 level of theory. Primarily, a possible reaction mechanism is obtained on the basis on IRC calculations using MP2 level of theory. To obtain true picture of the reaction path, we performed IRC calculations using CASSCF method with a minimal basis set 6-31G**. Some new equilibrium geometries and transition states have been identified at the CASSCF level. Energetics are also obtained at the QCISD(T)//CASSCF method. Possible reaction paths have been discussed, which are new in literature. Heat of reaction is found to be consistent with the experimental data. Bond dissociation energies to various dissociation paths are also reported.

The spectrum of high-energy γ rays accompanying spontaneous fission of $^{252}$Cf has been measured in γ-γ coincidence mode to search for the nucleus-nucleus coherent bremsstrahlung. The experiment was performed at the underground laboratory (555 meter depth) which provides a natural attenuation of the cosmic muon flux by a factor of 2 x 10$^{4}$. A total of 2.5 x 10$^{10}$ fission events were recorded but high-energy γ rays > 25 MeV were not observed at the level as reported in the previous experiments at surface level. The measurement provides a new upper limit at 95% confidence level of 5 x 10$^{−11}$ photons/(fission x MeV) for γ-ray emission from the nucleus-nucleus coherent bremsstrahlung in 25-180 MeV energy region, which is two orders of magnitude lower than the previous value. The result has been compared with the existing theoretical models. The fully quantum approach and potential barrier included Coulomb acceleration calculation predict two orders of magnitude and one order of magnitude higher emission probability, respectively, in 25-60 MeV energy range compared to the new upper limit indicating towards the modification of the theories.

The Hoyle analogue state in $$^{16}$$ O was explored by inelastic scattering of 45 MeV $$\alpha $$ s on a Mylar target. The break up 4 $$\alpha $$ s of $$^{16}$$ O have been detected in coincidence with the inelastically scattered $$\alpha $$ beam particle to probe the Hoyle analogue state of $$^{16}$$ O in complete kinematics, for the first time. The data have been analysed for all possible configurations and the excitation function of $$^{16}$$ O has been reconstructed directly from 4 $$\alpha $$ as well as for specific decay channels like $$^{12}$$ C(0 $$^{+}_{2}$$ ) + $$\alpha $$ , $$^{12}$$ C(3 $$^{-}_{1}$$ ) + $$\alpha $$ and $$^{8}$$ Be + $$^{8}$$ Be. Several previously known states have been observed above the $$4\alpha $$ break-up threshold (14.44 MeV) in the above mentioned decay channels. However, the signature of the 15.1 MeV state, most preferable to be the Hoyle analogue state according to the theoretical prediction, remains inconclusive.

Precise estimation of the rare direct 3α decay of the Hoyle state of 12C has been made to unveil its unusual α-cluster configurations ranging from linear 3α chain structure to diffuse Bose gas as well as Bose Einstein condensate. The present new high precision, nearly zero background experimental study with 1.6×105 Hoyle events has converged on the upper limit for direct decay at ∼0.019% with 95% confidence limit, which is more than a factor of 2 lower than the limit obtained in the previous studies. Keywords: 3α cluster state, 12C(α, α)3α reaction, Complete kinematics reaction, The Hoyle state decay, Direct versus sequential decay, Inelastic scattering

Background: The excitation energy dependence of the fission fragment mass and folding angle distributions for reactions with loosely bound projectiles are reported to be significantly different compared to the reactions with tightly bound nuclei. Extensive study to understand the reaction mechanism of weakly bound projectiles is required as it can simulate the mechanism of fission induced with radioactive ion beams.Purpose: The effect of loosely bound nuclei on fission fragment folding angle and mass distributions in the $^{9}\mathrm{Be}+^{238}\mathrm{U}$ reaction near the Coulomb barrier energies is investigated and the contributions of incomplete fusion fission in the total fission cross section are studied.Methods: Mass and folding angle distributions of the fission fragments have been measured near the Coulomb barrier energies using two large area multiwire proportional counters. Fragment masses were determined from the time-of-flight difference method. To understand the effect of breakup of loosely bound nuclei, the results are compared with tightly bound proton-, $\ensuremath{\alpha}$-particle-, and carbon-induced reactions, as well as with the predictions from semiempirical calculations.Results: The width of folding angle distributions is found to increase with lowering excitation energy in the $^{9}\mathrm{Be}+^{238}\mathrm{U}$ reaction. This is in contrast to the reaction $^{12}\mathrm{C}+^{232}\mathrm{Th}$ involving tightly bound projectiles, populating similar compound nuclei. The peak-to-valley ratios of the fission fragment mass distributions for all events are found to sharply increase with lowering excitation energy in the $^{9}\mathrm{Be}+^{238}\mathrm{U}$ reaction. The possible contribution of incomplete fusion into the total fission cross section could be extracted. The measured mass distributions were found to be consistent with the semiempirical calculation gef and macro-microscopic two-center shell model calculations considering the admixture of incomplete fusion fission.Conclusion: For actinide targets, mass distributions of inclusive fission are influenced by the breakup/transfer channels of the weakly bound projectiles. At the above-barrier energies, the contribution of incomplete fusion is found to be $\ensuremath{\approx}25\ifmmode\pm\else\textpm\fi{}4%$ which is similar to the reported value of the complete fusion suppression factor in reactions involving nuclei with low binding energies. The increase in the peak-to-valley ratio with lowering excitation energy in the fission fragment mass distribution could be explained by the combined analysis of folding angle and mass distributions.

One of the frontiers of today’s nuclear physics research is the synthesis of Super Heavy Elements (SHE). Fusion-fission dynamics, namely the competition between quasi fission and fusion is one of the key challenges to optimize the SHE. To have an insight into the dynamics, one requires the study of fission fragment mass and angular distribution near barrier energies for heavy-ion induced fission reactions. Recent successful installation of linear accelerators in India offers a unique opportunity to study the dynamics of nuclear reactions and formation process of SHE. For the effective utilization of these current, as well as upcoming facilities, development of novel detectors to study reaction dynamics, formation process of SHE with heavier projectiles and higher beam energies is needed. Gaseous detectors have undergone a rapid improvement in terms of spatial, temporal and energy resolution, rate capability, radiation hardness, ion feedback etc., ushering in a new genre of micro-structured devices based on semi-conductor technology, commonly known as Micro-Pattern Gaseous Detectors (MPGDs). Although many of the MPGD structures were primarily developed for high-rate tracking of charged particles in high energy physics experiments, stability of operation, simplicity of construction and relatively low cost make these detectors suitable for other applications, such as low-energy nuclear physics experiments. The present activities encompass a detailed evaluation of the operational conditions of Micromesh-Multi Wire and THGEM-Multi Wire hybrid detector operated in low-pressure isobutane gas with a view to optimizing their use in the detection of charged particles and fission fragments.

The fragment emission mechanism in the binary decay of composites formed in the reactions $^{20}\mathrm{Ne}+^{56}\mathrm{Fe}$ and $^{16}\mathrm{O}+^{58}\mathrm{Ni}$ has been studied at two different excitation energies. The inclusive energy and angular distributions of the emitted fragments $^{6,7}\text{Li}$, $^{7,8,9}\text{Be}$, $^{10,11}\text{B}$, and $^{11,12,13,14}\text{C}$ have been measured in the laboratory angles ranging from ${15}^{\ensuremath{\circ}}$ to ${35}^{\ensuremath{\circ}}$ (corresponding angles in center of mass ranging from ${20}^{\ensuremath{\circ}}$ to ${50}^{\ensuremath{\circ}}$). The energy distributions of the fragments are found to be Gaussian and peaked at energies higher than those expected from fusion-fission-type reactions. The center-of-mass angular distributions of all the fragments have been found to fall faster than $\ensuremath{\approx}1/\mathrm{sin}{\ensuremath{\theta}}_{\mathrm{c}.\mathrm{m}.}$-like dependence and the average $Q$ values of the fragments are found to decrease with increasing the center-of-mass angle of the emitted fragment for both the systems. The above characteristics of fragments signify that they were emitted from nonequilibrium sources, produced in a highly energy damped deep-inelastic-type reaction. The lifetimes of the dinuclear composites estimated from the angular distributions of these fragments are found to be in the range of $\ensuremath{\approx}(0.5--2.7)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}22}$ s, which are smaller than the respective compound-nuclear lifetimes $[\ensuremath{\approx}(1.0--2.0)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}21} \mathrm{s}]$. The angular-momentum dissipations estimated from the average kinetic energies of the fragments are found to be, for lighter fragments in particular, greater than those predicted by the empirical sticking limit.

The isospin dependence of nuclear level density has been investigated by analyzing the spectra of evaporated neutrons from excited $^{116}\mathrm{Sn}$ and $^{116}\mathrm{Te}$ nuclei. These nuclei are populated via $p+^{115}\mathrm{In}$ and $^{4}\mathrm{He}+^{112}\mathrm{Sn}$ reactions in the excitation energy range of 18--26 MeV. Because of low excitation energy, the neutron spectra are predominantly contributed by the first-chance decay leading to the $\ensuremath{\beta}$-stable $^{115}\mathrm{Sn}$ and neutron-deficient $^{115}\mathrm{Te}$ as residues for the two cases. Theoretical analysis of the experimental spectra has been performed within the Hauser-Feshbach formalism by employing different models of the level-density parameter. It is observed that the data could only be explained by the level-density parameter that decreases monotonically when the proton number deviates from the $\ensuremath{\beta}$-stable value. This is also confirmed by performing a microscopic shell-model calculation with the Woods-Saxon mean field. The results have strong implications on the estimation of the level density of unstable nuclei and calculation of astrophysical reaction rates relevant to $r$ and $rp$ processes.

The nuclear level density of $^{115}$Sn has been measured in an excitation energy range of $\sim $2 - 9 MeV using the experimental neutron evaporation spectra from the $^{115}$In($p,n$)$^{115}$Sn reaction. The experimental level densities were compared with the microscopic Hartree-Fock BCS (HFBCS), Hartree-Fock-Bogoliubov plus combinatorial (HFB+C), and an exact pairing plus independent particle model (EP+IPM) calculations. It is observed that the EP+IPM provides the most accurate description of the experimental data. The thermal properties (entropy and temperature) of $^{115}$Sn have been investigated from the measured level densities. The experimental temperature profile as well as the calculated heat capacity show distinct signatures of a transition from the strongly-paired nucleonic phase to the weakly paired one in this nucleus., This article has been submitted to European Journal of Physics A for publication

Neutron kinetic energy spectra in coincidence with low-energy $\ensuremath{\gamma}$-ray multiplicities have been measured around $A\ensuremath{\approx}110$ in the $^{16}\mathrm{O}+^{93}\mathrm{Nb}$ and $^{20}\mathrm{Ne}+^{93}\mathrm{Nb}$ reactions in a compound nuclear excitation energy range of $\ensuremath{\approx}90--140$ MeV. The excitation energy (temperature) dependence and the angular momentum (spin) dependence of the inverse level density parameter $k$ have been investigated by comparing the experimental data with statistical Hauser-Feshbach calculations. In contrast to the available systematic in this mass region, the inverse level density parameter showed an appreciable increase as a function of the excitation energy. The extracted $k$ values at different angular momentum regions, corresponding to different $\ensuremath{\gamma}$ multiplicities, also showed an overall increase with the average nuclear spins. The experimental results have been compared with a microscopic statistical-model calculation and found to be in reasonable agreement with the data. The results provide useful information to understand the variation of nuclear level density at high temperature and spins.

Background: The recent surprising experimental discovery of asymmetric fission in the nucleus $^{180}\mathrm{Hg}$ at low excitation energy has renewed interest concerning our understanding of the role of nuclear shell effects in the dynamics of the fission process. New theoretical models have been developed that claim to successfully explain the observed asymmetric fission of $^{180}\mathrm{Hg}$ and also predict the nature of mass distributions of several other preactinide nuclei for which experimental data are scarce.Purpose: We investigated fragment-mass distributions in the fission of the preactinide nucleus $^{214}\mathrm{At}$ at different excitation energies near the Coulomb barrier. The present results were compared with the predictions from a recent state-of-the-art theoretical calculation, as well as with our previous measurement for the nearby nucleus $^{210}\mathrm{Po}$.Methods: A pulsed heavy-ion beam was used in the experiment. Fission fragments were detected with two large-area position-sensitive multiwire proportional counters placed at the folding angle. Mass distributions were extracted from time-of-flight differences and position information ($\ensuremath{\theta},\ensuremath{\phi}$) for the fission fragments.Results: An asymmetry in fragment-mass distribution in the fission of $^{214}\mathrm{At}$ was observed at an excitation energy of $\ensuremath{\approx}31$ MeV, where a shell effect is found to influence the potential energy surface. At higher excitation energies, mass distributions are predominantly symmetric indicating the absence of shell effects.Conclusion: This finding is consistent with the prediction of a recent macroscopic-microscopic dynamical model. However, for the preactinides, static models with nascent fragment shell structure are likely to produce similar results.

The High-spin states in 195Tl, populated through the 185,187Re(13C, 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. Keywords: Nuclear Structure, γ-ray spectroscopy, Doubly degenerate bands, TRS calculation

The pre-scission and post-scission neutron multiplicities are measured for the 18O + 184W reaction in the excitation energy range of 67.23–76.37 MeV. Langevin dynamical calculations are performed to infer the energy dependence of fission decay time in compliance with the measured neutron multiplicities. Different models for nuclear dissipation are employed for this purpose. Fission process is usually expected to be faster at a higher beam energy. However, we found an enhancement in the average fission time as the incident beam energy increases. It happens because a higher excitation energy helps more neutrons to evaporate that eventually stabilizes the system against fission. The competition between fission and neutron evaporation delicately depends on the available excitation energy and it is explained here with the help of the partial fission yields contributed by the different isotopes of the primary compound nucleus.

Theoretical investigation on the reaction mechanism of X + O3 → XO + O2 (X = Cl, Br and I) reactions have been performed at the ab initio level using correlation consistent and effective core potential basis sets. The geometry and frequency of the reactants, products, equilibrium geometries and transition states are obtained using MP2 level of theory and energetics are calculated at the CCSD(T) and QCISD(T) methods. Heat of reactions are found to be consistent with the experimental data. Possible reaction pathways are discussed. In case of reactions of ozone with chlorine and brome, it starts producing a nonplanar trioxide (OOOX) transition state with acute dihedral angle. It then proceeds via nonplanar equilibrium geometry and transition state. Finally dissociates to XO + O2 from a planar O2·OX equilibrium geometry. For the reaction with iodine, initial transition state and equilibrium geometry with acute dihedral angle are disappeared. The reaction proceeds through planar intermediates and finally dissociated to IO + O2 via O2·OI isomer. There exists a flat plateau on the potential energy surface in the intermediate region for all the cases. Finding of O2·OX equilibrium geometry strengthens the suggestion of previous investigations and for the possibility of direct reaction mechanism. High level theoretical investigation including reaction dynamics on these reactions can reveal the actual reaction mechanism.

Goat pox disease outbreaks were observed in different places affecting Black Bengal Goats in West Bengal (WB) and Tellicherry, Vembur and non-descriptive breeds in Tamil Nadu (TN) causing severe lesions and mortality up to 30%. Clinical specimens from all the outbreaks were screened by polymerase chain reaction followed by restriction fragment length polymorphism (PCR-RFLP) and confirmed the diseases as Goat Pox. Virus isolation in Vero cell line was done with randomly selected ten samples, cytopathic effects (CPE) characterized by syncytia and intracytoplasmic inclusion bodies were observed after several blind passages. Nucleotide sequence of complete p32 gene using randomly selected two isolates and three clinical specimens revealed presence of Goat pox virus (GTPV)-specific signature residues in all the sequences. Phylogenetic analysis using the present five sequences along with GenBank data of GTPV complete p32 gene sequences showed all the GTPV sequences cluster together except Pellor strain (NC004003) and FZ Chinese strain (KC951854). The five sequences either from WB or TN cluster more closely with GTPV isolates of Maharashtra state that were responsible for cross species outbreak of pox disease in both sheep (KF468759) and goats (KF468762) in India during the year 2010. All the Indian goat pox viruses, including the Mukteswar strain, isolated in 1946 and sequence reported in 2004 clustered together with the GTPVs causing the recent outbreaks. It was observed that GTPVs caused similar clinical manifestation irrespective of their geographical locations and breed characteristics, no variation observed among the Indian isolates based on p32 gene over the period of seventy years and disease outbreaks could not be observed or reported in vaccinated goats.

The phenomenon of collective enhancement in nuclear level density and its fadeout has been probed using neutron evaporation study of two strongly deformed ( 173 Lu, 185 Re), and one spherical ( 201 Tl) compound nuclei over the excitation energy ( E ⁎ ) range of ∼ 22 – 56 MeV . Clear signature of the fadeout of collective enhancement in nuclear level density was observed for the first time in both the deformed evaporation residues 172 Lu and 184 Re at an excitation energy range ∼ 14 – 21 MeV . Calculations based on finite temperature density functional theory, as well as macroscopic–microscopic shape transition model, have strongly established a close correlation between the observed fadeout of collective enhancement and a deformed to spherical nuclear shape transition in these nuclei occurring in the same excitation energy zone. Interestingly, a weak signature of fadeout has also been observed for the spherical residue 200 Tl. This is due to a similar shape transition of the deformed excited state configuration of 200 Tl.

Efficiency corrected single ratios of neutron and proton spectra in central Sn112+112Sn and Sn124+124Sn collisions at 120 MeV/u are combined with double ratios to provide constraints on the density and momentum dependencies of the isovector mean-field potential. Bayesian analyses of these data reveal that the isoscalar and isovector nucleon effective masses, ms⁎−mv⁎ are strongly correlated. The linear correlation observed in ms⁎−mv⁎ yields a nearly independent constraint on the effective mass splitting Δmnp⁎=(mn⁎−mp⁎)/mN=−0.05−0.09+0.09δ. The correlated constraint on the standard symmetry energy, S0 and the slope, L at saturation density yields the values of symmetry energy S(ρs)=16.8−1.2+1.2 MeV at a sensitive density of ρs/ρ0=0.43−0.05+0.05.

The excited states of 169Tm have been studied via the 169Tm(32S,32S′)169Tm* reaction at the beam energy of 164MeV. The $\gamma$-rays were detected using the Indian National Gamma Array (INGA) setup, composed of 19 Compton-suppressed clover HPGe detectors. A new level scheme of 169Tm with 11 newly placed $ \gamma$-rays has been proposed. A band crossing in the $ \pi [541]1/2^{-}$ band and several interband E1 transitions between this and the $ \pi [411]1/2^{+}$ ground-state band have been observed for the first time in this nucleus. The role of the $N=98$ deformed shell gap has been discussed by comparing the band crossing parameters of the negative parity bands in Tm and other neighboring nuclei. The origin of the interband E1 transitions has been investigated in terms of coupling to octupole degrees of freedom. The shape evolution of the Tm isotopes around $ N=98$ have been studied in the projected and cranked shell model approaches, both of which predict a change in shape from an axial prolate to a triaxial one after band crossing in these nuclei. The new data and the calculations help to understand the unusual structural phenomena reported for the nuclei with $ N=98$.

Fission fragment mass distributions have been measured for relatively neutron-deficient compound nuclei, $^{188}\mathrm{Pt}$ and $^{190}\mathrm{Pt}$, formed in the fusion reactions, $^{28}\mathrm{Si}+^{160}\mathrm{Gd}$ and $^{12}\mathrm{C}+^{178}\mathrm{Hf}$, respectively. The data were obtained for a similar initial excitation energy range of 49--68 MeV for both the systems. The fragment mass distributions for both the Pt isotopes were found to be single peaked and no appreciable change in the mass symmetry was observed throughout the measured excitation energy range, for both the reactions. However, relatively broader mass distributions observed in the fission of $^{188}\mathrm{Pt}$ in the studied energy domain indicates the presence of fission events originating from a nonequilibrated source as well. This signifies that the mass equilibrium has not been fully achieved in the $^{28}\mathrm{Si}+^{160}\mathrm{Gd}$ system as compared to the $^{12}\mathrm{C}+^{178}\mathrm{Hf}$ system, indicating the presence of quasifission events in the former reaction.

The excited states of $^{197}\mathrm{Tl}$ have been studied via $^{197}\mathrm{Au}(^{4}\mathrm{He}$, $4\mathrm{n})^{197}\mathrm{Tl}$ reaction at a beam energy of 50 MeV from the K-130 cyclotron at the Variable Energy Cyclotron Centre (VECC). The $\ensuremath{\gamma}$ rays were detected using the VECC array for Nuclear Spectroscopy (VENUS) with six Compton-suppressed clover HPGe detectors. An improved level scheme of $^{197}\mathrm{Tl}$ has been proposed from this work, which has been extended to 5.1 MeV of excitation energy and 39/2 $\ensuremath{\hbar}$ of spin from the placement of 28 new $\ensuremath{\gamma}$-ray transitions. Band crossings in the known one- and three-quasiparticle (qp) bands have been identified for the first time in this work. Two new bands, based on 3-qp and 5-qp configurations, have been observed for the first time in this nucleus; both of which are identified as the magnetic rotational (MR) in nature. The excitation energies of these bands are similar to that of the doubly degenerate bands observed for the similar 3-qp and 5-qp configurations in $^{195}\mathrm{Tl}$. These indicate a transition from an aplanar geometry of the neutron, proton, and the core angular momentum vectors to a planar one for neutron number $N\ensuremath{\ge}116$ in Tl isotopes. The total Routhian surface calculations suggest a change in shape from oblate for the 1-qp configuration to a near-spherical one for the 3- and 5-qp configurations. This is consistent with the observed MR nature of the bands with multi-qp configuration. The MR bands are well reproduced by a model calculations in the frame work of the shears mechanism with the principal axis cranking.

Fission fragment mass distribution has been measured for $^{28}\mathrm{Si}+^{197}\mathrm{Au}$ reaction at bombarding energies around the Coulomb barrier (${V}_{b}=126.5\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$). The experimental variance of the mass distribution shows a sudden change from monotonic decrease to a saturation at energies close to the Coulomb barrier and again a decreasing trend at sub-barrier energies. The variance of the mass distribution was also obtained from dynamical and statistical model calculations for the fission of a fully equilibrated compound nucleus. Both of the theoretical calculations show a monotonic change of the mass variance around the Coulomb barrier. The anomalous dependence of fission fragment mass width at energies around the barrier may be due to the dominance of the quasifission process as compared to compound nuclear fission.

A large 4$\pi$ array of charged particle detectors has been developed at Variable Energy Cyclotron Centre to facilitate high resolution charged particle reaction and spectroscopy studies by detecting event-by-event the charged reaction products emitted in heavy ion reactions at energy $\sim$ 10-60 MeV/A. The forward part ($\theta \sim \pm $ $7^{0}$ - $\pm 45^{0}$) of the array consists of 24 highly granular, high resolution charged particle telescopes, each of which is made by three layers [single sided silicon strip($\Delta$E) + double sided silicon strip (E/$\Delta$E) + CsI(Tl)(E)]of detectors. The backward part of the array consists of 112 CsI(Tl) detectors which are capable of detecting primarily the light charged particles (Z $\le$ 2) emitted in the angular range of $\theta \sim \pm $ $45^{0}$ - $\pm 175^{0}$. The extreme forward part of the array ($\theta \sim \pm $ $3^{0}$ - $\pm 7^{0}$) is made up of 32 slow-fast plastic phoswich detectors that are capable of detecting light (Z $\le$2) and heavy charged particles (3 $\le$ Z $\lesssim$ 20) as well as handling high count rates. The design, construction and characterization of the array has been described., Comment: Paper has been submitted in NIMA

Self-supported polyethylene and deuterated polyethylene targets of thickness in the range of 0.3 mg/cm2 to 2.5 mg/cm2 were prepared using the solvent casting technique. A quantitative estimation of material required for the solvent casting technique has been presented. Overall target preparation time has been reduced from the earlier reported methods. Comparative studies between polyethylene of the two different isotopes (hydrogen/deuterium) were performed in terms of their different characteristic properties e.g. target thickness, uniformity in the target thickness, infrared transmission and melting temperature. The effect of deuteration is clearly seen in the infrared transmission and melting point of the polyethylene, which may have potential applications in other fields of research. Target prepared in this work has been used for an in-beam experiment, where yield of the deuteron produced is found to be sensitive to the hydrogen isotope present in the polyethylene target.

A comparative study on the dielectric properties (in 100 Hz to 40 MHz frequency range) of a pure and silver nano particle dispersed (0.25% and 0.50% by weight) Liquid crystal compound, 6O.4 and the resultant changes at the molecular level using Laser Raman Spectroscopy is reported. The dielectric anisotropy of the two samples was found to be negative but the magnitude of the anisotropy slightly decreased due to the dispersion of the nanoparticles and the relaxation frequency in nematic phase was found to increase with the temperature and the concentration of nanoparticles. Raman spectroscopy studies on pure and SNP dispersed 6O.4 confirms the modification in molecular polarizability in SNP dispersed sample.

After publication of the paper, the authors realized that one of the references was not correct. Its correct version appears in this erratum.

The cyclotron at Variable Energy Cyclotron Centre (VECC), Kolkata, has recentlyrecently completed its 40 years of operation in 2017. During the past four decades, VECC has been able to cross several milestones in exploring the properties of nuclei with the help of low energy light as well as heavy ions accelerated by the cyclotron. In this review, we endeavour to present an overall picture of the intense research activities in various branches of nuclear physics carried out in the past four decades using cyclotron, with special emphasis on the important achievements in each field.

An attempt was made to assess the gonadosomatic index (GSI) of an indigenous coldwater fish Schizothorax richardsonii commonly known as ?Asela? in Uttarakhand is one of the most important sports fishery in the state. The fish inhibits in streams and rivers of Himalayan and Sub- Himalayan regions. The gonadosomatic index of both captive reared and wild stocks of both Female and Male Schizothorax richardsonii was calculated which ranges from 5.72% to12.91% and 1.80% to 7.24% in captive reared Female and Male fish respectively. While in wild brooders ranges from 5.33% to 14.10% and 1.52% to 6.74% in Female and Male respectively. Gonadosomatic index will be helpful thus, gives an idea about maturity level in fishes as well as estimation of breeding season.

Energy spectra of light charged particles emitted in the reaction $p + {}^{27}\mathrm{Al} \rightarrow {}^{28}\mathrm{Si}^{\ast}$ have been studied and compared with statistical model calculation. Unlike 16O + 12C where a large deformation was observed in 28Si*, the energy spectra of $\alpha$ -particles were well explained by the statistical model calculation with standard “deformability parameters” obtained using the rotating liquid drop model. It seems that the $\alpha$ -clustering in the entrance channel causes extra deformation in 28Si* in the case of 16O + 12C, but the reanalysis of other published data shows that there are several cases where extra deformation was observed for composites produced via non- $\alpha$ -cluster entrance channels also. An empirical relation was found between mass-asymmetry in the entrance channel and deformation, which indicates that along with $\alpha$ -clustering, mass-asymmetry may also affect the emission of a light charged particle.

The aim of this work was to compare the efficacy of a commercially available phytogenic feed additive (PFA) and an antibiotic growth promoter, which was bacitracin methylene disalicylate (BMD), on performance, nutrient retention, caecal colonization of bacteria and humoral immune responses against Newcastle disease in broiler chickens challenged orally with Salmonella enteritidis and Escherichia coli. One-day-old male Cobb 400 broiler chicks (n = 120) were fed with 1) a negative control (NC) diet, which is the basal diet without any added growth promoter, 2) a positive control (PC) diet, the basal diet supplemented with BMD, 500 mg/kg and 3) a diet supplemented with PFA (150 mg/kg) for 39 days and the birds were inoculated with S. enteritidis and E. coli on d 28. Supplementation of PFA improved body weight, feed conversion ratio, retention of N and crude fiber, increased fecal moisture content and decreased digesta transit time as compared with the NC and PC groups (P < 0.01). Both the PC and the PFA was found to be equally effective in controlling the surge in numbers of Salmonella and E. coli following oral inoculation of these bacteria as compared with the NC group (P < 0.05) at 24 h past inoculation. Caecal content analysis on d 39 indicated lower numbers of Salmonella, E. coli and Clostridium in the PC and PFA groups as compared with the NC group (P < 0.05). The number of Lactobacillus in the PFA group was higher than those in the NC and PC groups (P < 0.05). Humoral immune response, measured as hemagglutination inhibition titer against Newcastle disease, was better in the PC and PFA groups compared with the NC group (P < 0.05) at d 21 but the difference did not last till d 39. The heterophil to lymphocyte ratio was narrower (P < 0.001) and alkaline phosphatase activity was higher (P < 0.01) in the PFA group as compared with the NC and PC groups on d 39. It was concluded that the PFA, which is animal, environment and consumer friendly, may be used as an effective replacement for common in-feed antibiotics like BMD to enhance broiler performance especially when the birds are exposed to heavy infections on fields. Keywords: Broilers, Phytogenic feed additives, Performance, Nutrient retention, Enteric challenge, Intestinal microbiology

A straight-run flock of 1-day-old Cobb 400 chicks (n = 432) was distributed into four treatment groups (9 replicate pens in each group, 12 birds in a pen) for a 38-day feeding trial evaluating the effects of a methionine chelate (Met-TM)- or a yeast proteinate (Yeast-TM)-based supplement of copper (Cu), iron (Fe), manganese (Mn) and zinc (Zn) on growth performance, bone criteria and some metabolic indices in commercial broiler chickens. The diets were either not supplemented with any trace elements at all (negative control, NC) or supplemented with an inorganic (sulphate) trace element premix (inorganic TM (ITM), 1 g/kg feed), the Met-TM (1 g/kg feed) and the Yeast-TM (0.5 g/kg feed). Body weight, feed conversion ratio and dressed meat yield at 38 days were better in the Yeast-TM-supplemented group as compared with the NC, ITM and Met-TM groups (p

Background: The influence of shell effect on the dynamics of the fusion fission process and its evolution with excitation energy in the preactinide Hg-Pb region in general is a matter of intense research in recent years. In particular, a strong ambiguity remains for the neutron shell closed $^{210}\mathrm{Po}$ nucleus regarding the role of shell effect in fission around $\ensuremath{\approx}30--40\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$ of excitation energy.Purpose: We have measured the fission fragment mass distribution of $^{210}\mathrm{Po}$ populated using fusion of $^{4}\mathrm{He}+^{206}\mathrm{Pb}$ at different excitation energies and compare the result with recent theoretical predictions as well as with our previous measurement for the same nucleus populated through a different entrance channel. Mass distribution in the fission of the neighboring nuclei $^{213}\mathrm{At}$ is also studied for comparison.Methods: Two large area multiwire proportional counters (MWPC) were used for complete kinematical measurement of the coincident fission fragments. The time of flight differences of the coincident fission fragments were used to directly extract the fission fragment mass distributions.Results: The measured fragment mass distribution for the reactions $^{4}\mathrm{He}+^{206}\mathrm{Pb}$ and $^{4}\mathrm{He}+^{209}\mathrm{Bi}$ were symmetric and the width of the mass distributions were found to increase monotonically with excitation energy above 36.7 MeV and 32.9 MeV, respectively, indicating the absence of shell effects at the saddle. However, in the fission of $^{210}\mathrm{Po}$, we find minor deviation from symmetric mass distributions at the lowest excitation energy (30.8 MeV).Conclusion: Persistence of shell effect in fission fragment mass distribution of $^{210}\mathrm{Po}$ was observed at the excitation energy $\ensuremath{\approx}31\phantom{\rule{0.16em}{0ex}}\mathrm{MeV}$ as predicted by the theory; at higher excitation energy, however, the present study reaffirms the absence of any shell correction in the fission of $^{210}\mathrm{Po}$.

Schizothorax richardsonii, commonly called as spotted snow trout, is a coldwater hillstream fish. It is a delicious fish and is important from sportive and commercial point of view. The hillstream modifications comprise presence of irregular folds of skin acting as papillated suckers on the ventral side of the head, closely situated smaller eyes, small gill openings, reduced air bladder and short-stumpy barbells. Body is spotted, slender and sub-cylindrical. It is a phytophagous fish with an adaptation in its mouth to scrap algae from the submerged rocks. Spotted snow trout can spawn naturally as well as artificially by stripping. Sexual dimorphism is vivid during breeding season. It starts spawning after second year. Spawning takes place twice in a year- October/November and March/April. Eggs are of sticky nature. Relative and absolute fecundities have been found about 12,000 and 30,000 eggs/kg respectively. Optimum temperature for incubation is 15-20°C and it takes about 11-18 days for hatching. S. richardsonii has low to moderate vulnerability in Nepal. The population of the fish is decreasing rapidly due to heavy fishing pressure, natural calamity and human disturbances.

The prediction of Hoyle state was necessitated to explain the abundance of carbon, which is crucial for the existence of life on Earth and is the stepping stone for understanding the abundance of other heavier elements. After the experimental confirmation of its existence, soon it was realized that the Hoyle state was ‘different’ from other excited states of carbon, led to intense theoretical and experimental activities over the past few decades to understand its structure. In recent times, precision, high statistics experiments on the decay of Hoyle state have been performed at the Variable Energy Cyclotron Centre, to determine the quantitative contributions of various direct 3 α decay mechanisms of the Hoyle state. The present results have been critically compared with those obtained in other recent experiments and their implications have been discussed.

In India, approximately 15–20% of Run of Mine (ROM) from any iron ore deposit is reported to slime dam as a byproduct of the iron ore beneficiation process. The proportion of iron ore slime to ROM will increase in the future, with a higher proportion of lean-grade ores in ROM. Furthermore, tonnages of iron ore slime will increase with increasing demand of iron concentrate. Presently, this slime is stored in a dam in the absence of beneficiation technology. A beneficiation flowsheet was developed at Tata Steel based on detailed beneficiation studies in the laboratory and bench scale. This process, on commercialization, will produce a concentrate of 2.2% alumina with 40–45% yield from slime of 7–9% alumina. The Fe content in the reject will be less than 40%, thus adhering to the regulatory norm. In this paper, results of bench-scale studies are discussed along with required characterization findings of feed and products. On commercialization, this process would provide solution to an urgent environmental co...

1. In a 42-d feeding trial, 264 one-d-old, as hatched, Cobb 400 broiler chickens (6 pens per group, n = 11 per pen in a 2 × 2 factorial arrangement) were fed on two concentrations of dietary calcium (Ca) (9.0 and 7.5 g/kg in starter, 7.5 and 6 g/kg in grower phases) and supplemental phytase (0 and 500 U/kg diet). 2. During d 0-21, the high Ca + phytase diet improved body weight. During d 0-42, feed intake was increased by the low Ca diet and decreased by phytase supplementation. Feed conversion ratio during d 0-21 was improved by the high Ca + phytase diet. 3. At d 42, Ca in duodenal digesta was reduced by low dietary Ca and supplemental phytase. High dietary Ca reduced P in duodenal and jejunal digesta. Phytase reduced digesta P and increased serum P concentration. 4. Relative tibia length decreased with low dietary Ca and increased with phytase. The robusticity index of tibia was improved by the low Ca diet and phytase supplementation. Phytase supplementation increased tibia ash and concentrations of Ca, magnesium (Mg), manganese (Mn), copper (Cu), zinc (Zn) and iron (Fe) in tibia. The low Ca diet increased Mg, Mn and Fe and reduced Cu and Zn in tibia. 5. It was concluded that 7.5 g Ca/kg during weeks 0-3 and 6 g Ca/kg during weeks 3-6 sustained broiler performance and bone ash, while phytase supplementation facilitated tibia mineralisation, particularly during the grower phase.

T-box genes are important development regulators in vertebrates with specific patterns of expression and precise roles during embryogenesis. They encode transcription factors that regulate gene transcription, often in the early stages of development. The hallmark of this family of proteins is the presence of a conserved DNA binding motif, the "T-domain." Mutations in T-box genes can cause developmental disorders in humans, mostly due to functional deficiency of the relevant proteins. Recent studies have also highlighted the role of some T-box genes in cancer and in cardiomyopathy, extending their role in human disease. In this review, we focus on ten T-box genes with a special emphasis on their roles in human disease.

T-box genes are important development regulators in vertebrates with specific patterns of expression and precise roles during embryogenesis. They encode transcription factors that regulate gene transcription, often in the early stages of development. The hallmark of this family of proteins is the presence of a conserved DNA binding motif, the "T-domain." Mutations in T-box genes can cause developmental disorders in humans, mostly due to functional deficiency of the relevant proteins. Recent studies have also highlighted the role of some T-box genes in cancer and in cardiomyopathy, extending their role in human disease. In this review, we focus on ten T-box genes with a special emphasis on their roles in human disease.

Oxygen uptake (VO 2 ) through the gills of a hill-stream fish Glyptothorax telchitta from the Saptakoshi river (Nepal) has been studied in relation to different body weights. The oxygen uptake was determined at 24.0±1°C using a cylindrical glass respirometer with continuous water flow system. The aquatic oxygen uptake through the gills increased from 1.048 to 8.115 mlO 2 kg -1 .h -1 within the body weight range of 3.215 to 31.355 g. A fish of 17.052 g average body weight consumes 4.461 mlO 2 -1 .h -1 . The relation between oxygen uptake (VO 2 ) and body weight was determined by performing regression analysis using logarithmic transformation. It has been found that with a unit increase in body weight, the oxygen uptake per unit time (mlO 2 h -1 ) increases by a power of 0.930 showing significant positive correlation whereas, the weight specific oxygen uptake decreases by a power of 0.070 showing significant but negative correlation. DOI: http://dx.doi.org/10.3126/njbs.v1i0.7464 Nepalese Journal of Biosciences 1: 11-18 (2011)

Neutron evaporation spectra have been measured from $^{4}\mathrm{He}+^{208}\mathrm{Pb}$ and $^{4}\mathrm{He}+^{209}\mathrm{Bi}$ reactions by using $^{4}\mathrm{He}$-ion beams of several bombarding energies. Excitation-energy dependence of the level density parameter has been studied for the two systems in the excitation energy range of $\ensuremath{\sim}18$--50 MeV. For both the reactions an overall reduction of the asymptotic level density parameter with increasing excitation energy (temperature) is observed. The trend of the data was compared with the Thomas--Fermi model predictions and found to be in reasonable agreement. The value of the shell damping parameter has been extracted from the lowest-energy data in the case of $^{210,211}\mathrm{Po}$ and $^{211,212}\mathrm{At}$ nuclei close to the $Z=82$ and $N=126$ shell closure, and it was found to be consistent with the recent measurement in the vicinity of doubly magic $^{208}\mathrm{Pb}$ nucleus.