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Fusion cross sections have been measured for the asymmetric system $^{16}\mathrm{O}+^{165}\mathrm{Ho}$ at energies near and deep below the Coulomb barrier with an aim to investigate the occurrence of fusion hindrance for the system. Cross sections down to $\ensuremath{\approx}700$ nb have been measured using the off-beam $\ensuremath{\gamma}$-ray technique. The fusion cross sections have been compared with the coupled channel calculations. The energy onset of fusion hindrance appears to occur at ${E}_{\mathrm{c}.\mathrm{m}.}=57\ifmmode\pm\else\textpm\fi{}0.85$ MeV, where a deviation in the slope of the experimental logarithmic derivative compared to that of coupled channel calculations has been observed. This is in agreement with the value obtained from the touching point configuration of the adiabatic model.

The excitation function for quasielastic scattering of the weakly bound projectile $^{6}\mathrm{Li}$ on a $^{159}\mathrm{Tb}$ target, at large backward angle, has been measured at energies around the Coulomb barrier. The corresponding quasielastic barrier distribution has been extracted from the experimental cross sections, both including and excluding the $\ensuremath{\alpha}$ particles produced in the reaction. The quasielastic scattering cross sections, excluding the $\ensuremath{\alpha}$ particles, have been analyzed in the framework of coupled channels calculations. The centroid of the quasielastic barrier distribution, including the $\ensuremath{\alpha}$ particles, is found to shift towards higher energy relative to the centroid of the fusion barrier distribution for the system. This has been attributed to the low $\ensuremath{\alpha}$-breakup threshold of the nucleus $^{6}\mathrm{Li}$.

In this work $\mathit{n}$-transfer and incomplete fusion cross sections for the $^{9}\mathrm{Be}+^{197}\mathrm{Au}$ system are reported over a wide energy range, ${\mathrm{E}}_{\mathrm{c}.\mathrm{m}.}\ensuremath{\approx}29\text{\ensuremath{-}}45$ MeV. The experiment was carried out using the activation technique and off-line $\ensuremath{\gamma}$ counting. The transfer process is found to be the dominant mode as compared to all other reaction channels. Detailed coupled reaction channel (CRC) calculations have been performed for $\mathit{n}$-transfer stripping and pickup cross sections. The measured $1\mathit{n}$-stripping cross sections are explained with CRC calculations by including the ground state and the ${2}^{+}$ resonance state ($E=3.03$ MeV) of $^{8}\mathrm{Be}$. The calculations for $1\mathit{n}$-pickup cross sections, including only the ground state of $^{10}\mathrm{Be}$ agrees reasonably well with the measured cross sections, while it overpredicts the data at subbarrier energies. For better insight into the role of the projectile structure in the transfer process, a comprehensive analysis of the $1\mathit{n}$-stripping reaction has been carried out for various weakly bound projectiles on a $^{197}\mathrm{Au}$ target nucleus. The transfer cross sections scaled with the square of the total radius of interacting nuclei show the expected $Q$-value dependence of the $1\mathit{n}$-stripping channel for weakly bound stable projectiles.

Quasielastic scattering excitation function at large backward angle has been measured for the weakly bound system $^{7}\mathrm{Li}+^{159}\mathrm{Tb}$ at energies around the Coulomb barrier. The corresponding quasielastic barrier distribution has been derived from the excitation function, both including and excluding the $\ensuremath{\alpha}$ particles produced in the reaction. The centroid of the barrier distribution obtained after inclusion of $\ensuremath{\alpha}$ particles was found to be shifted higher in energy, compared with the distribution excluding the $\ensuremath{\alpha}$ particles. The quasielastic data, excluding the $\ensuremath{\alpha}$ particles, have been analyzed in the framework of continuum discretized coupled-channels calculations. The quasielastic barrier distribution for $^{7}\mathrm{Li}+^{159}\mathrm{Tb}$, has also been compared with the fusion barrier distribution for the system.

The origin of the large $\alpha$ particle production and incomplete fusion in reactions involving weakly-bound $\alpha$+$x$ cluster nuclei still remains unresolved. While the (two-step) process of breakup followed by capture of the ``free" complementary fragment ($x$) is widely believed to be responsible, a few recent studies suggest the dominant role of (direct) cluster stripping. To achieve an unambiguous experimental discrimination between these two processes, a coincidence measurement between the outgoing $\alpha$ particles and $\gamma$ rays from the heavy residues has been performed for the $^7$Li($\alpha$+triton)+$^{93}$Nb system. Proper choice of kinematical conditions allowed for the first time a significant population of the region accessible only to the direct triton stripping process and not to breakup followed by the capture of the ``free'' triton (from the three-body continuum). This result, also supported by a cluster-transfer calculation, clearly establishes the dominance of the direct cluster-stripping mechanism in the large alpha production.

To probe the role of the intrinsic structure of the projectile on subbarrier fusion, measurement of fusion cross sections has been carried out in a $^{9}\mathrm{Be} + ^{197}\mathrm{Au}$ system in the energy range ${E}_{\mathrm{c}.\mathrm{m}.}/{V}_{B}\phantom{\rule{4pt}{0ex}}\ensuremath{\approx}$ 0.82 to 1.16 using off-beam $\ensuremath{\gamma}$-counting method. Measured fusion excitation function has been analyzed in the framework of the coupled-channel approach using CCFULL code. It is observed that the coupled-channel calculations, including couplings to the inelastic state of the target and the first two states of the rotational band built on the ground state of the projectile, provide a very good description of the subbarrier fusion data. At above-barrier energies, the fusion cross section is found to be suppressed by $\ensuremath{\approx}39(2)%$ as compared to the coupled-channel prediction. A comparison of reduced excitation function of $^{9}\mathrm{Be} + ^{197}\mathrm{Au}$ with other $x + ^{197}\mathrm{Au}$ shows a larger enhancement for $^{9}\mathrm{Be}$ in the subbarrier region amongst $Z=2--5$ weakly and tightly bound projectiles, which indicates the prominent role of the projectile deformation in addition to the weak binding.

To disentangle the role of shell effects and dynamics, fission fragment mass distributions of 191Au, a nucleus in the newly identified island of mass asymmetric fission in the sub-lead region, have been measured down to excitation energy of ≈20 MeV above the fission barrier via two different entrance channels, viz. 16O+175Lu and 37Cl+154Sm reactions. Apart from having signature of the shell effects in both the cases, clear experimental evidence of quasifission has been observed in the mass distributions of the Cl induced reaction, that has also been substantiated by the theoretical calculations. This crucial evidence along with a systematic analysis of the available experimental data has revealed that the dynamics in the entrance channel has significant influence on most of the reactions used earlier to explore the persistence of recently discovered mass asymmetry in β-delayed fission at low energy in this mass region, ignoring which might lead to ambiguity in interpreting the heavy-ion data. Keywords: Fusion-fission, Mass asymmetric fission, Shell effects, Quasifission

The effect of the shell structure of the target nuclei ($^{89}\mathrm{Y}$ and $^{93}\mathrm{Nb}$) on reaction mechanisms involving the weakly bound $^{7}\mathrm{Li}$ projectile has been investigated via a comparative study of different processes. Measurements of direct breakup, nucleon transfer leading to the ejectile in bound as well as unbound states, and elastic scattering have been carried out for the $^{7}\mathrm{Li}+^{89}\mathrm{Y}$ system at three different energies near the Coulomb barrier. An extensive analysis of this comprehensive data set was carried out using coupled channel calculations and compared with a previous similar study for the $^{7}\mathrm{Li}+^{93}\mathrm{Nb}$ system. The observed cross sections at low target excitations for nucleon transfer reactions correlate with the vacancies in the valance orbitals.

The complete and incomplete fusion along with one neutron stripping and pickup cross sections for the $^{6}\mathrm{Li}+^{124}\mathrm{Sn}$ system are measured using online and offline characteristic $\ensuremath{\gamma}$-ray detection techniques. The complete fusion (CF) cross sections at energies above the Coulomb barrier are found to be suppressed by $\ensuremath{\sim}34%$ compared to the coupled channel calculations. This suppression observed in complete fusion cross sections is found to be commensurate with the measured total incomplete fusion (ICF) cross sections. There is a distinct feature observed in the ICF cross sections, i.e., $d$ capture is found to be dominant than $\ensuremath{\alpha}$ capture at all the measured energies, contrary to the data available for $^{6}\mathrm{Li}+^{209}\mathrm{Bi},^{197}\mathrm{Au}$ systems. The total fusion cross section ratio between $^{6}\mathrm{Li}$ and $^{7}\mathrm{Li}$ induced reactions shows an increasing trend as the energy decreases below the barrier while it remains unity at above-barrier energies. A simultaneous explanation of complete, incomplete, and total fusion (TF) data is also obtained from the calculations based on the continuum discretized coupled channel method with short-range imaginary potentials. The cross section ratios of CF/TF and ICF/TF obtained from the data as well as the calculations shows the dominance of ICF at below-barrier energies and CF at above-barrier energies.

Evidence from multiple studies supports the concept that both glomerular filtration and proximal tubule (PT) reclamation affect urinary albumin excretion rate. To better understand these roles of glomerular filtration and PT uptake, we investigated these processes in two distinct animal models. In a rat model of acute exogenous albumin overload, we quantified glomerular sieving coefficients (GSC) and PT uptake of Texas Red-labeled rat serum albumin using two-photon intravital microscopy. No change in GSC was observed, but a significant decrease in PT albumin uptake was quantified. In a second model, loss of endogenous albumin was induced in rats by podocyte-specific transgenic expression of diphtheria toxin receptor. In these albumin-deficient rats, exposure to diphtheria toxin induced an increase in albumin GSC and albumin filtration, resulting in increased exposure of the PTs to endogenous albumin. In this case, PT albumin reabsorption was markedly increased. Analysis of known albumin receptors and assessment of cortical protein expression in the albumin overload model, conducted to identify potential proteins and pathways affected by acute protein overload, revealed changes in the expression levels of calreticulin, disabled homolog 2, NRF2, angiopoietin-2, and proteins involved in ATP synthesis. Taken together, these results suggest that a regulated PT cell albumin uptake system can respond rapidly to different physiologic conditions to minimize alterations in serum albumin level.

The reaction mechanism of deep-inelastic multinucleon transfer processes in the $^{16}\mathrm{O}\phantom{\rule{0.16em}{0ex}}+\phantom{\rule{0.16em}{0ex}}^{27}\mathrm{Al}$ reaction at an incident $^{16}\mathrm{O}$ energy (${E}_{\mathrm{lab}}=134$ MeV) substantially above the Coulomb barrier has been studied both experimentally and theoretically. Elastic-scattering angular distribution, total kinetic energy loss spectra, and angular distributions for various transfer channels have been measured. The $Q$-value- and angle-integrated isotope production cross sections have been deduced. To obtain deeper insight into the underlying reaction mechanism, we have carried out a detailed analysis based on the time-dependent Hartree-Fock (TDHF) theory. A recently developed method, TDHF+GEMINI, has been applied to evaluate production cross sections for secondary products. From a comparison between the experimental and theoretical cross sections, we find that the theory qualitatively reproduces the experimental data. Significant effects of secondary light-particle emissions are demonstrated. Possible interplay among fusion-fission, deep-inelastic, multinucleon transfer, and particle evaporation processes is discussed.

In beam test experiments have been carried out for particle identification using digital pulse shape analysis in a 500~$\mu$m thick Neutron Transmutation Doped (nTD) silicon detector with an indigenously developed FPGA based 12 bit resolution, 1 GHz sampling digitizer. The nTD Si detector was used in a low-field injection setup to detect light heavy-ions produced in reactions of $\sim$ 5 MeV/A $^{7}$Li and $^{12}$C beams on different targets. Pulse height, rise time and current maximum have been obtained from the digitized charge output of a high bandwidth charge and current sensitive pre-amplifier. Good isotopic separation have been achieved using only the digitized charge output in case of light heavy-ions. The setup can be used for charged particle spectroscopy in nuclear reactions involving light heavy-ions around the Coulomb barrier energies., Comment: 7 pages, 8 figures

Fusion cross sections for the $^{11}\mathrm{B}+^{197}\mathrm{Au}$ system have been measured at energies around and deep below the Coulomb barrier, to probe the occurrence of fusion hindrance in case of asymmetric systems. A deviation with respect to the standard coupled channels calculations has been observed at the lowest energy. The results have been compared with an adiabatic model calculation that considers a damping of the coupling strength for a gradual transition from sudden to adiabatic regime at very low energies. The data could be explained without inclusion of the damping factor. This implies that the influence of fusion hindrance is not significant within the measured energy range for this system. The present result is consistent with the observed trend between the degree of fusion hindrance and the charge product that reveals a weaker influence of hindrance on fusion involving lighter projectiles on heavy targets.

High-spin band structures of $^{200}\mathrm{Tl}$ have been studied by $\ensuremath{\gamma}$-ray spectroscopic methods using the $^{198}\mathrm{Pt}(^{7}\mathrm{Li},5n)^{200}\mathrm{Tl}$ reaction at 45 MeV of beam energy. The level scheme of $^{200}\mathrm{Tl}$ has been extended significantly and several new band structures have been established with the observation of 60 new transitions. The $\ensuremath{\pi}{h}_{9/2}\ensuremath{\bigotimes}\ensuremath{\nu}{i}_{13/2}$ oblate band has been extended beyond the particle alignment frequencies. The band structures and the other excited states have been compared with the neighboring odd-odd Tl isotopes. Total Routhian surface calculations have been performed to study the deformation and shape changes as a function of spin in this nucleus. These calculations could reproduce the particle alignment frequency and suggest that the neutron pair alignment in $\ensuremath{\nu}{i}_{13/2}$ orbital induces $\ensuremath{\gamma}$ softness in $^{200}\mathrm{Tl}$.

The two-step process of transfer followed by breakup is explored by measuring a rather complete set of exclusive data for reaction channels populating states in the ejectile continua of the $^{7}\mathrm{Li}+^{93}\mathrm{Nb}$ system at energies close to the Coulomb barrier. The cross sections for $\ensuremath{\alpha}+\ensuremath{\alpha}$ events from one proton pickup were found to be smaller than those for $\ensuremath{\alpha}+d$ events from one neutron stripping and $\ensuremath{\alpha}+t$ events from direct breakup of $^{7}\mathrm{Li}$. Coupled-channels Born approximation and continuum-discretized coupled-channels calculations describe the data well and support the conclusion that the $\ensuremath{\alpha}+d$ and $\ensuremath{\alpha}+\ensuremath{\alpha}$ events are produced by direct transfer to unbound states of the ejectile.

Cluster state formation viz. the population of unbound 8 Be and the Hoyle state of 12 C produced in the reactions 12 C (77 MeV ) + 12 C and 13 C (75 MeV ) + 12 C have been studied using resonance particle spectroscopy. It was observed that there is a large difference in the cluster state formation in these two reactions and the yield of neutron rich isotopes of different fragments is more in the 13 C + 12 C compared to 12 C + 12 C reactions at 6 MeV/u.

A novel graft copolymer of acrylic acid onto poly(vinyl alcohol) has been synthesized and it is cross-linked by glutaraldehyde for the investigation of its efficiency in removing lead ion from aqueous solution. The chemical nature of the ion exchange resin has been elucidated with the help of chemical, spectral, and thermal analysis. Particle size, surface area, ion exchange capacity, optimum pH, time, and temperature for Pb(II) adsorption were determined. Metal ion adsorption kinetics, isotherms, and thermodynamics have been studied. A plausible mechanism for lead ion exchange has been suggested.

A novel graft copolymer of acrylic acid onto poly(vinyl alcohol) has been synthesized and it is crosslinked by methylene bisacrylamide for the investigation of its efficiency in removing lead ion from aqueous solution. The chemical nature of the ion exchange resin has been elucidated with the help of chemical test, FTIR, TGA and DSC. Particle size (0.20 mm), surface area (85.6 m2/g), ion exchange capacity (5.3 meq H+/g), optimum pH (4.5), time (60 min) and temperature (40°C) for Pb(II) adsorption were determined. Metal ion adsorption kinetics, isotherms and thermodynamics have been studied. A plausible mechanism for lead ion exchange has been suggested.

In a randomised double-blind trial carried out on fit, unpremedicated patients undergoing standard minor operations with early postoperative mobility, using a standard form of anaesthesia, pretreatment with diazepam 0.15 mg/kg or midazolam 0.1 mg/kg failed to reduce significantly the incidence of postoperative muscle pains following suxamethonium 1 mg/kg. By contrast, tubocurarine 0.05 mg/kg proved to be effective as a pretreatment. Neither benzodiazepine influenced the incidence or severity of fasciculations seen with suxamethonium or the duration of neuromuscular block. Tubocurarine virtually abolished visible fasciculation and, in the dose used, reduced the intensity and duration of the neuromuscular block. There were no clinically significant changes in serum potassium, creatinine phosphokinase or aldolase after suxamethonium, although 5 out of 47 showed an atypical rise in creatinine phosphokinase.

Single- and multi-nucleon transfer reactions, namely, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{20}\mathrm{O})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{19}\mathrm{O})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{17}\mathrm{O})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{16}\mathrm{O})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{18}\mathrm{N})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{17}\mathrm{N})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{16}\mathrm{N})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{15}\mathrm{N})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{14}\mathrm{N})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{16}\mathrm{C})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{15}\mathrm{C})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{14}\mathrm{C})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{13}\mathrm{C})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{12}\mathrm{C})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{12}\mathrm{B})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{11}\mathrm{B})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{10}\mathrm{B})$, $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{10}\mathrm{Be})$, and $^{206}\mathrm{Pb}(^{18}\mathrm{O},^{9}\mathrm{Be})$, have been studied at an incident $^{18}\mathrm{O}$ energy of 139 MeV. The total kinetic energy loss (TKEL) spectrum and angular distribution of reaction products have been measured. The $Q$ value and angle integrated cross sections are deduced. Angular distributions for the elastically scattered $^{18}\mathrm{O}$ particles are also measured. Fully microscopic time-dependent Hartree-Fock (TDHF) calculations, based on the independent single-nucleon transfer mode, have been carried out and are compared with experimental data of multinucleon transfer reactions. The TDHF calculations provide reasonable agreement with the experimental data for cases where one- and two-nucleon transfer is involved; the discrepancy is large for multinucleon transfer reactions. The effect of particle evaporation on the production cross sections has been studied. Inclusion of particle evaporation effects, though improving the results, could not reproduce the measured cross sections. Possible origins of these discrepancies are discussed.

Elastic scattering measurement for the $^{9}\mathrm{Be}+^{89}\mathrm{Y}$ system has been carried out at near-barrier energies with the aim of investigating the effect of breakup on the elastic channel. The energy dependence of the optical model potential for the system gives an indication of the breakup threshold anomaly (BTA) for the system. An overall repulsive real part of the dynamic polarization potential (DPP) generated due to continuum couplings using the $\ensuremath{\alpha}+^{5}\mathrm{He}$ cluster structure for $^{9}\mathrm{Be}$ is consistent with the BTA behavior observed for the system. In contrast, an attractive real part of the DPP, at all energies, is observed for similar calculations carried out using the $^{8}\mathrm{Be}+n$ cluster structure. Coupling of the 1$n$ transfer channel in addition to continuum couplings does not have a significant effect on the elastic scattering angular distributions. The experimental 1$n$ transfer cross sections show better agreement with the corresponding values obtained using the $^{8}\mathrm{Be}+n$ cluster structure calculations. Inclusive breakup-$\ensuremath{\alpha}$ cross sections are observed to form a large fraction of the reaction cross sections, especially at below-barrier energies, suggesting the dominance of the breakup channel at these energies. This also supports the BTA behavior observed for the system, reflected as the presence of a reaction channel and thus the persistence of the imaginary potential at below-barrier energies.

This is a retrospective study of 27 cases of congenital short colon with anorectal malformation (pouch colon syndrome) treated during the last 5 years (from January 1991 to December 1995). The radiological feature of enormously dilated colonic pouch occupying more than half the width of abdomen was diagnostic in almost all cases. Excision of pouch and end enterostomy was associated with maximum survival (92.3%) in good risk patients. Proximal diverting enterostomy with decompression and irrigation of pouch is a preferable alternative to pouch colostomy in poor risk patients. Tapering coloplasty and colostomy should be reserved only for types I and II cases of pouch colon.

Complete fusion cross sections for ${}^{7}$Li+${}^{144,152}$Sm reactions have been measured at energies around the Coulomb barrier by offline $\ensuremath{\gamma}$-counting technique. Measured cross sections for the above two reactions are found to be similar at energies well above the Coulomb barrier, however, at sub-barrier energies the cross sections for the ${}^{7}$Li+${}^{152}$Sm system are much higher compared to the ${}^{7}$Li+${}^{144}$Sm system, manifesting the effect of target deformation. Cross sections for the present reactions at above-barrier energies are found to be larger than previously measured reactions involving ${}^{6}$Li projectile with the same targets, possibly due to smaller breakup probability of ${}^{7}$Li than ${}^{6}$Li. Coupled-channels calculations show that the experimental fusion cross sections for both the systems are enhanced at subbarrier energies and suppressed at above-barrier energies compared to the respective one-dimensional barrier penetration model predictions. The calculations by different models show that the measured complete fusion cross sections at above-barrier energies are suppressed up to $\ensuremath{\sim}$25% compared to the theoretical predictions. It also reveals that a large part of the suppression could be due to inelastic and transfer coupling.

The high spin structure of ${}^{201}$Tl has been studied by $\ensuremath{\gamma}$-ray spectroscopic method using the ${}^{198}$Pt(${}^{7}$Li,4$n$)${}^{201}$Tl reaction at 45 MeV beam energy. The level scheme of ${}^{201}$Tl has been considerably extended through the observation of 31 new transitions. Several new band structures have been established. The 9/2${}^{\ensuremath{-}}$ oblate band has been significantly extended beyond the particle alignment frequencies. The band structures and the other excited states have been compared with the neighboring odd-$A$ Tl isotopes and with the even-even core nucleus ${}^{200}$Hg. The total Routhian surface calculations have been performed to study the deformation and shape changes as a function of spin in this nucleus.

Quasielastic scattering cross sections for the reaction 7 Li+159 Tb have been measured at large backangles, at energies around the Coulomb barrier. The quasielastic barrier distribution has been extracted from the measured quasielastic scattering excitation function, including and excluding α particle contribution. The peak of the quasielastic barrier distribution including α particle contribution shows a shift towards higher energy compared to the peak of the distribution without α particles. The quasielastic barrier distribution when compared to the calculated fusion barrier distribution, appears to show reasonable agreement for the system.

Two cluster structures of 9Be namely, 5He+4He and 8Be+n have been considered for its breakup to describe the available data on elastic scattering for 9Be projectile with 28Si, 64Zn and 144Sm targets. The results of these calculations suggest that the breakup coupling effects are significant for 5He+4He cluster model at above the barrier energies, while they are dominant at relatively lower energies for 8Be+n model. The addition of one neutron stripping channel in the 8Be+n model gives an overall good description of the elastic data for all the systems considered. The couplings generated by breakup in 8Be+n model have different behaviour than the coupling effects obtained within the 5He+4He model, the former being more prominent at lower energies and for the heavier target systems. The behaviour of extracted dynamic polarisation potentials (DPP) generated due to breakup and one neutron transfer couplings have been investigated., Comment: Accepted in Phys. Rev. C

With the aim to investigate the in∞uence of the breakup channel on difierent reaction channels, the elastic scattering and fusion of 9 Be with the medium mass target 89 Y has been stud- ied at near barrier energies. Optical model analysis of the elastic data has been carried out and a dispersion relation applied to the real and imaginary potentials to investigate their energy depen- dence from which the presence of breakup threshold anomaly has been observed. Complete fusion (CF) cross sections, obtained for 9 Be+ 89 Y system, are found to be suppressed by (20 § 5)% as compared to the coupled-channels calculations without breakup coupling. This observation has been further conflrmed by comparing these cross sections with those for the 4 He+ 93 Nb and 12 C+ 89 Y systems, where fusion is induced by a tightly bound projectile and forms a nearby compound nu- cleus to that formed by 9 Be+ 89 Y. Results from the breakup coupling done in continuum discretized coupled-channels calculations show that the elastic cross sections thus obtained, which also flt the experimental elastic cross sections, are enhanced compared to the uncoupled calculations which im- plies a reduction in absorption/fusion cross sections. These enhanced cross sections suggest that the dynamic polarization potential produced due to breakup coupling is repulsive in nature. Thus the efiective (bare+polarization) potential around the barrier becomes less attractive leading to the absence of the normal threshold anomaly.

The $\ensuremath{\alpha}$-particle energy spectra have been measured in coincidence with fission fragments over a wide range of relative angles with respect to fragment emission direction in the ${}^{11}$B (62 MeV) $+$ ${}^{232}$Th reaction. The $\ensuremath{\alpha}$-particle multiplicity spectra have been fitted with moving source model to extract the prescission (${\ensuremath{\alpha}}_{\mathrm{pre}}$) and near-scission (${\ensuremath{\alpha}}_{\mathrm{nse}}$) components. The present results, along with available data from the literature over a wide range of ${Z}^{2}/A$ and the excitation energy of a compound system, have been analyzed to develop certain global features of the pre- and near-scission emission characteristics. It is seen that ${\ensuremath{\alpha}}_{\mathrm{pre}}$ values when normalized to ${E}_{\mathit{CN}}^{2.3}$ (${E}_{\mathit{CN}}$ is the compound nucleus excitation energy) show a systematic linearly increasing trend with the $\ensuremath{\alpha}$-particle emission $Q$ value (${Q}_{\ensuremath{\alpha}}$). The fraction of near-scission multiplicity is observed to be nearly the same at around 10% of the total prescission multiplicity for all the systems.

Aplasia cutis congenita is a rare congenital anomaly where skin is missing over part of the body. Most of the cases are present on the scalp. We present a case of ACC where skin was absent over the lumbosacral area. It was associated with meningomyelocoel.

Online tracking of human activity against a complex background is a challenging task for many applications. In this paper, we have developed a robust technique for localizing skin colour regions from unconstrained image frames. A simple and fast segmentation algorithm is used to train a multiplayer perceptron (MLP) for detection of skin colours. Stepper motors are synchronized with the MLP to track the movement of the skin colour regions.

Fragment emission mechanisms have been studied in 12 C on 12 C and 13 C on 12 C reactions at same excitation energy. The inclusive energy distributions of the complex fragments (3≤ Z≤ 5) emitted from the composite system have been measured in the angular range 14 0 to 36 0 . The present experiments have been performed with the motivation to study the isotopic dependence of fragment yields in these two reactions. From the preliminary analysis, it has been observed that fragments are emitted from a completely equilibrated and long lived composite system for both 12 C + 12 C and 13 C + 12 C reactions. It has also been observed that the emission of neutron-rich fragments are more in 13 C + 12 C compared to 12 C + 12 C reaction.

A retrospective study of 11 cases of choledochal cyst over a period of 10 years is presented. There were 8 females and 3 males in a ratio of 2.67∶1. The classical triad of jaundice, mass and abdominal pain was seen in none of our patients. Ultrasonography was diagnostic in 9 out of 11 (80%) patients. Surgical procedures performed were, complete excision of the cyst with Roux en Y hepaticojejunostomy (nine cases), internal drainage of the cyst (one case) and excision of the extrahepatic cyst with Roux en Y hepaticojejunostomy in one case of Type IV choledochal cyst. One patient died in the immediate postoperative period. Others have remained well upto 10 years follow-up. We recommend total cyst excision with hepaticojejunostomy as the treatment of choice.

Caudal duplication is a rare entity due to incomplete separation of mono-ovular twins. It is usually associated with various congenital malformations involving mainly the genitourinary and gastrointestinal tracts. We report such a case operated upon successfully in which there was no other associated anomaly.

A 4 year old girl with progressive distension of abdomen and previous history of blunt abdominal trauma was found to have bile ascites due to left hepatic duct (LDH) injury. The management with a brief review of literature is discussed below.