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Supplemental Digital Content is available in the text., Background: Cardiac involvement among hospitalized patients with severe coronavirus disease 2019 (COVID-19) is common and associated with adverse outcomes. This study aimed to determine the prevalence and clinical implications of COVID-19 cardiac involvement in young competitive athletes. Methods: In this prospective, multicenter, observational cohort study with data from 42 colleges and universities, we assessed the prevalence, clinical characteristics, and outcomes of COVID-19 cardiac involvement among collegiate athletes in the United States. Data were collected from September 1, 2020, to December 31, 2020. The primary outcome was the prevalence of definite, probable, or possible COVID-19 cardiac involvement based on imaging definitions adapted from the Updated Lake Louise Imaging Criteria. Secondary outcomes included the diagnostic yield of cardiac testing, predictors for cardiac involvement, and adverse cardiovascular events or hospitalizations. Results: Among 19 378 athletes tested for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection, 3018 (mean age, 20 years [SD, 1 year]; 32% female) tested positive and underwent cardiac evaluation. A total of 2820 athletes underwent at least 1 element of cardiac triad testing (12-lead ECG, troponin, transthoracic echocardiography) followed by cardiac magnetic resonance imaging (CMR) if clinically indicated. In contrast, primary screening CMR was performed in 198 athletes. Abnormal findings suggestive of SARS-CoV-2 cardiac involvement were detected by ECG (21 of 2999 [0.7%]), cardiac troponin (24 of 2719 [0.9%]), and transthoracic echocardiography (24 of 2556 [0.9%]). Definite, probable, or possible SARS-CoV-2 cardiac involvement was identified in 21 of 3018 (0.7%) athletes, including 15 of 2820 (0.5%) who underwent clinically indicated CMR (n=119) and 6 of 198 (3.0%) who underwent primary screening CMR. Accordingly, the diagnostic yield of CMR for SARS-CoV-2 cardiac involvement was 4.2 times higher for a clinically indicated CMR (15 of 119 [12.6%]) versus a primary screening CMR (6 of 198 [3.0%]). After adjustment for race and sex, predictors of SARS-CoV-2 cardiac involvement included cardiopulmonary symptoms (odds ratio, 3.1 [95% CI, 1.2, 7.7]) or at least 1 abnormal triad test result (odds ratio, 37.4 [95% CI, 13.3, 105.3]). Five (0.2%) athletes required hospitalization for noncardiac complications of COVID-19. During clinical surveillance (median follow-up, 113 days [interquartile range=90 146]), there was 1 (0.03%) adverse cardiac event, likely unrelated to SARS-CoV-2 infection. Conclusions: SARS-CoV-2 infection among young competitive athletes is associated with a low prevalence of cardiac involvement and a low risk of clinical events in short-term follow-up.

The study of complete and incomplete fusion dynamics in Ne 20 + 59 Co system at projectile energies ≈62–150 MeV using recoil-catcher activation technique followed by offline gamma-ray spectroscopy has been done. The excitation functions for the evaporation residues produced in the reaction channels 63Zn(3αp3n), 62Zn(3αp4n) and 60Cu(4α3n) have been measured. The excitation functions for these evaporation residues have been compared with theoretical predictions based on code PACE-2. The observed enhancements in the measured cross-sections over their theoretical predictions for the α-emitting channels indicate the presence of incomplete fusion. The incomplete fusion fraction (FICF) has also been deduced and compared with those obtained for few earlier measurements. It has been observed that the incomplete fusion contributes significantly along with complete fusion even at lower projectile energies and it increases with increasing the projectile energies. Mass-asymmetry systematic is found to be projectile structure dependent rather than a simple linear growth with increasing the mass-asymmetry between interacting partners. Further, the deformation of the target is also found to affect the incomplete fusion dynamics. The present results show that the incomplete fusion dynamics does not depend completely on a single entrance channel parameter, but it also depends on multi entrance channel parameters namely; entrance channel mass-asymmetry, α-Q-value of the projectile, Coulomb factor (ZPZT) and deformation of the target or deformation parameter ( β 2 ). All these parameters are found to play an important role in the dynamics of incomplete fusion.

Low lying states of 150Sm have been studied through decay spectroscopy of odd–odd 150Pm, populated with 150Nd(p, n)150Pm reaction at E b e a m = 8.0 MeV using 97% enriched 150Nd target and detecting the γ-rays with the VENUS array comprised of six Compton suppressed Clover HPGe detectors. Nineteen new transitions are placed, four tentative γ-rays are confirmed and eight transitions are found to have altered placements; consequently assigning thirteen new levels to the decay scheme of 150Pm. The spin-parity assignments of the excited levels of 150Sm were made based on logft and angular correlation analysis.

A radioelemental assemblage assessment of two beaches of Odisha is performed for the first time. The radiation is measured in two ways, both on field with the help of a hand held environmental survey meter and in the laboratory, where the concentrations of radionuclide's 238 U, 232 Th and 4 K have been determined with the help of High Purity Germanium detector (HPGe). Mineralogical analysis of selected samples has been performed with the help of X-Ray Fluorescence Spectrometry (XRF). A marked difference between the concentration of Uranium (274 Bq kg −1 ) and Thorium (2489 Bq kg −1 ) is observed and discussed based on the geology of the area. The placer deposits showing an enrichment of thorium can be an important source of nuclear fuel for the thorium based nuclear reactors. The ratio of thorium and uranium concentrations gives us an idea about the coastal processes associated with the beach. Statistical analysis of the data shows a positive correlation between 238 U and 232 Th and a strong negative correlation is indicated between 4 K and 238 U, 232 Th. A cross plot between the equivalent thorium and the equivalent uranium and the equivalent thorium and potassium, represents the nature of deposition and its association with the heavy mineral along with the radioactive elements. Heavy minerals exhibit an increasing trend towards Northeast-Southwest along the south eastern coast of India.

The ability of charged particle activation analysis (CPAA) to determine at trace level of arsenic directly in ground water has been reported in this paper. The CPAA has been applied to determine total arsenic, As(III) and As(V) species in ground water collected from eastern part of India using ~16 MeV proton beam. The speciation of As(III) and As(V) was carried out using DOWEX 1 × 8 resin. The total arsenic concentrations were also determined by other conventional techniques for validation and values are in good agreement with that obtained by CPAA. As(III) concentration was found to be double than that of As(V) in ground water sample.

The excitation functions of 93mMo and 91m,92m,95m,gNb produced from alpha-induced reactions on 93Nb were measured from their respective threshold to 39.5 MeV. The study was conducted using the alpha beam from the Variable Energy Cyclotron Centre (VECC), Kolkata, India, the stacked foil activation technique and the off-line gamma ray spectrometric technique. The integral yields for a thick target were also deduced from the measured cross-sections and the stopping power of niobium. The results were compared with earlier reported data as well as with the theoretical values obtained from the TENDL-2013 library based on the TALYS-1.6 code.

Coal based power accounts for 70 % of energy generation in India. In this study, radiological characterization around Kolaghat Thermal Power Plant was undertaken. Radiochemical analysis of coal, ash and soil samples was performed using High purity germanium (efficiency 50 %). The characterization was done based on ‘Radium equivalent activity’, dose rate and hazard index. High radioactivity was observed within a radius of 500 m from the ash ponds and it decreased beyond 500 m. The overall radioactivity of the area was observed ~3–4 times higher than the prescribed limit, and the hazard index was estimated as unity.

Three different types of experiments have been performed to explore the complete and incomplete fusion dynamics in heavy-ion collisions. In this respect, first experiment for the measurement of excitation functions of the evaporation residues produced in the 20Ne + 165Ho system at projectile energy ranges ≈2–8 MeV /nucleon has been done. Measured cumulative and direct cross-sections have been compared with the theoretical model code PACE-2, which takes into account only the complete fusion process. It has been observed that, incomplete fusion fraction is sensitively dependent on projectile energy and mass asymmetry between the projectile and the target systems. Second experiment for measuring the forward recoil range distributions of the evaporation residues produced in the 20Ne + 165Ho system at projectile energy ≈8 MeV /nucleon has been done. It has been observed that, some evaporation residues have shown additional peaks in the measured forwardrecoil range distributions at cumulative thicknesses relatively smaller than the expected range of the residues produced via complete fusion. The results indicate the occurrence of incomplete fusion involving the breakup of 20Ne into 4He + 16O and /or 8Be + 12C followed by one of the fragments with target nucleus 165Ho. Third experiment for the measurement of spin distribution of the evaporation residues produced in the 16O + 124Sn system at projectile energy ≈6 MeV /nucleon, showed that the residues produced as incomplete fusion products associated with fast α and 2 α-emission channels observed in the forward cone, are found to be distinctly different from those of the residues produced as complete fusion products. The spin distribution of the evaporation residues also inferred that in incomplete fusion reaction channels input angular momentum (J 0) increases with fusion incompleteness when compared to complete fusion reaction channels. Present observation clearly shows that the production of fast forward α-particles arises from relatively larger angular momentum in the entrance channel leading to peripheral collision.

Kinetics of sorption of Pu(IV) by smectite-rich clay has been studied at varying metal ion concentrations. Different concentrations were achieved using different isotopes of Pu, namely, 239Pu, 238Pu and 237Pu. 237Pu was produced by alpha induced reaction on 235U, followed by radiochemical separation of Pu from irradiated U3O8 target. The concentrations used are above and below the solubility of Pu(IV) under neutral pH conditions, thereby, indicating the mechanism of sorption reactions of Pu(IV) in typical laboratory experiments and field level observations. Kinetics of Pu(IV) at 10−13 M concentration was found to be fast whereas at higher metal concentration the rate is governed by a slow step, indicating the role of formation of Pu(IV) polymeric species at the sorbent surface.

Chitosan is naturally occurring bio-polymer having strong affinity towards transition metal ions. Chitosan complexed with transition metal ions takes up inorganic arsenic anions from aqueous medium. In present work, As(V) sorption in the chitosan complexed with different metal ions like Cu(II), Fe(III), La(III), Mo(VI) and Zr(IV) were studied. Sorptions of As(V) in CuS embedded chitosan, (3-aminopropyl) triethoxysilane (APTS) embedded chitosan, epichlorohydrin (ECH) crosslinked chitosan and pristine chitosan were also studied. 74As radiotracer was prepared specifically for As(V) sorption studies by irradiation of natural germanium target with 18 MeV proton beam. The sorption studies indicated that Fe(III) and La(III) complexed with chitosan sorbed 95 ± 2% As(V) from aqueous samples in the pH range of 3–9. However, Fe(III)-chitosan showed better sorption efficiency (91 ± 2%) for As(V) from seawater than La(III)-chitosan (80 ± 2%). Therefore, Fe(III)-chitosan was selected to prepare the self-supported membrane and poly(propylene) fibrous matrix supported sorbent. The experimental As(V) sorption capacities of the fibrous and self-supported Fe(III)-chitosan sorbents were found to be 51 and 109 mg g−1, respectively. These materials were characterized by XRD, SEM and EDXRF, and used for preconcentration of As(V) in aqueous media like tap water, ground water and seawater. To quantify the As(V) preconcentrated in Fe(III)-chitosan, the samples were subjected to instrumental neutron activation analysis (INAA) using reactor neutrons. As(V) separations were carried out using a two compartments permeation cell for the self-supported membrane and flow cell using the fibrous sorbent. The total preconcentration of arsenic content was also explored by converting As(III) to As(V).

The thermal behavior of hafnium dioxide fiber has been investigated with the aid of time differential perturbed angular correlation (TDPAC) technique along with XRD and SEM measurements. This study has proved a good thermal stability of the fibrous material up to 1173 K and the fiber loses its crystallinity to a meager extent at 1673 K. No phase transition has been observed up to 1673 K in this fiber. TDPAC parameters for the HfO 2 fiber annealed at 1173 K are ω Q =124.6 (3) Mrad/s and η =0.36 (1). These values remain unaltered for the HfO 2 fiber annealed even at 1673 K. Electronic structure calculations based on the density functional theory (DFT) for HfO 2 doped with tantalum impurity have been performed and the calculated EFG parameters are in reasonable agreement with the experimental values.

An experiment has been performed to explore the incomplete fusion (ICF) reaction dynamics in heavy ion induced reactions. Excitation functions (EFs) for eighteen evaporation residues (ERs) produced in the system Ne 20 + Ho 165 have been measured in the energy range ≈ 88 – 164 MeV . Some of the ERs have significant contribution from precursor decay, which has been separated out from the measured cumulative cross-sections to get direct production cross-sections. Parameters of the statistical model code PACE-2 are optimized to reproduce the ERs populated in complete fusion reactions such as in xn and pxn channels. Using the same parameters, EFs for the residues produced in α-particle(s) emission channels have been calculated. A significant enhancement in the measured EFs of the ERs produced in α-particle(s) emission channels over the PACE-2 predictions have been observed which indicates the occurrence of incomplete fusion reaction process. In the ICF process the break-up of projectile 20Ne into He 4 + O 16 and/or Be 8 + C 12 takes place followed by fusion of one of the fragments with the target nucleus 165Ho. The present data analyses suggest that probability of incomplete fusion reaction increases with projectile energy. The ICF fraction F ICF has been estimated and found to increase with increasing mass-asymmetry [ A T / ( A T + A P ) ] of the partners in entrance channel. It is also observed that critical angular momentum associated with incomplete fusion channels at higher projectile energy may be associated with l-values lower than that of peripheral collisions, indicating that the incomplete fusion competes with complete fusion even at angular momentum values little lower than critical angular momentum.

The textural and mineralogical characteristics of subsurface sediments along with Ground Penetrating Radar (GPR) data collected along the Western margin of India were used to understand the depositional environments and the provenance of sediments. Textural attributes such as mean, standard deviation, skewness and Kurtosis show fluctuations due to fluvio-marine interaction and it is well understood that the bottom sediments are enriched with muddy sand, which may be deposited by mean of tidal invasion. The abundance of very coarse silt to very fine sand indicates the prevalence of low energy environment. The Linear Discriminate Function analysis indicates the fluvio marine deposition of sediments under low energy condition. GPR data upto a depth of 5 m shows the stratigraphic sequences of very fine sands and coarse silt. Optically Stimulated Luminescence (OSL) dating of sediments implies that the tidal sediments had deposited between ~30 ± 1 and ~90 ± 4 years before Present. XRD studies results the dominance of K-feldspar and deficiency of clay minerals, indicating that most of the sediments are derived from hinterland. Studies indicate that the Provenance of sediments in the Mandvi area is not related to Indus delta even though a considerable part of Gulf sediments are deposited by the Indus River.

The determination of the natural radioactivity has been carried out, by means of gamma-ray spectrometry, in exposed rock samples collected from various geological formations across the Singhbhum Shear Zone of India. The spatial variation in the concentration of primordial radionuclides reflects, in general, the geochemical variance among the analyzed rocks and affirms the earlier views on genesis of uranium mineralization. This study further speculates new possibilities of thorium depletion during shearing and metamorphism. All the obtained U-values were more than the worldwide average U-concentration (which is about 40 Bq/kg). Interestingly, U-concentration in mica schists from Singhbhum group of rocks and in slates and argillaceous quartzites from Iron Ore group of rocks was five to seven times higher than the global values. In contrast, the granites in study area showed comparatively lower U-concentration. The overall results suggest the control of complex metamorphism and shearing on U-distribution in the terrane. The contribution of 238U, 232Th and 40K to the total radiation dose in the study area was found to be significant ranging from 110 to 310 nGy/h in comparison with the lower global, as well as Indian average values.

This paper is devoted to the comparative study of the radon flux vs. uranium content and radon flux vs. porosity for mineral samples from some typical Indian rocks (schists, quartzites, argillaceous quartzites, slates and granites) used as building materials, primarily around the Singhbhum Shear Zone, Jharkhand State. As the radon flux of any particular rock type was investigated with reference to its uranium activity and porosity, a good concordance of porosity on radon flux was observed. Such a significant influence of porosity on radon flux was also observed when different rock types were inter-compared. For example, granite that is commonly considered as typical source of indoor radon showed depleted level of radon flux when compared to most other rocks in the study area. In case of rocks such as slates and argillaceous quartzites, low porosity exhibited reduced radon flux in spite of their enhanced radioactive source content. It is concluded that it may not be advisable to utilize materials that are uranium depleted for construction purposes without giving importance to the materials' porosity.

Eleven cobalt (11) complexes of type [Co(L)6]Br2 (where L=imidazole, pyridine, peperidine, piperazine, indole, benzimidazole, benzotriazole, triazole, quinoline, iso-qunoline, carbazole) have been synthesized and are well characterized by elemental analysis, IR. UV. Mass Spectra and magnetic measurement. All these complexes are soluble in ethanol and the conductance measurement shows that all these complexes are of 1: 2 type electrolyte. The IR spectra indicate the coordination between the central cobalt atom and nitrogen atom of the ligands. In the mass spectra molecular ion peak of these complexes appear at appropriate place. The thermo gravimetric analysis shows the strong bond between the central cobalt atom and bromine atom of the complexes. In the complexes the ligands are loosely attached to the central cobalt atom as these are removed first on heating. Finally considering all the spectral analysis conductance values, thermo gravimetric analysis, conductance values octahedral structure are proposes for these complexes

Aqueous dispersions of highly stable, redispersible silver nanoparticles (Ag NPs) were synthesized using gamma radiolysis with gum acacia as a protecting agent. The formation of nanosized silver was confirmed by its characteristic surface plasmon absorption peak at around 405 nm in UV–vis spectra. The size of the silver nanoparticles can be tuned by controlling the radiation dose, ratio of gum acacia to silver ions and also the ionic strength of the medium. Dynamic light scattering (DLS) measurement of the as-synthesized nanoparticles indicated the size less than 3 nm at higher dose of radiation and this also corroborated the size measurement from the width of the corresponding X-ray diffraction (XRD) peak. The face centered cubic (fcc) crystallinity of the nanoparticles was evident from XRD and high resolution transmission electron microscopic (HRTEM) measurements. Fourier transform infra-red (FTIR) spectroscopic data indicate a bonding of Ag NPs with COO � group of acacia through bridging

The thin layer activation technique using a heavy ion beam has been applied to measure the erosion loss of materials by electrical spark discharges with a discharge current in the mA range. Since the range of heavy ions such as 14 N, 16 O and 20 Ne, is about one order less than that of light ions such as p, d and α, the total activity can be generated within a narrow layer by activation with heavy ions. In the present work, a narrow layer of activity of ∼27 μm thickness was produced in copper-based materials by heavy ion induced nuclear reactions using 110 MeV 16 O ions to measure the surface erosion in the range of hundreds of nanometers to few microns. The sensitivity can be enhanced to tens of nanometers using suitable heavy ions.

The beach placer deposits in the southern coastal Orissa, India may have significant levels of radiation due to the presence of Th and U bearing minerals such as monazite and zircon. In this study, Gopalpur and Rushikulya beach regions were selected to study the ambient radiation environment. The average activity concentrations of radioactive elements such as 232Th, 238U and 40K of beach sand samples were measured by γ-ray spectrometry using a HPGe detector, and found to be much higher than the internationally accepted values. The cross plots of eTh/eU and eTh/K inferred that the sand samples of Gopalpur and Rushikulya beach placer deposit were deposited in leached uranium and an oxidising environment. The absorbed γ dose rate levels of the study areas are similar to other monazite sand-bearing HBRAs of southern and southwestern coastal regions of India and of world. Different radiation hazard indices were estimated for the present study area and were found to be much higher than the internationally accepted values. Hence, Gopalpur and Rushikulya beach placer region can be considered as a high background radiation area and a potential zone for radiogenic heavy mineral exploration.

Excitation functions and differential recoil range distributions in the interaction of 16 O with 75 As have been measured to investigate complete and incomplete fusion reactions. The measured cross sections were compared with theoretical calculations using the computer code ALICE-91. The results indicated predominant incomplete fusion processes in the production of near target products. This was further confirmed by recoil range distribution studies of the products at 104 MeV of beam energy. The relative contributions of complete and incomplete fusion channels are estimated from recoil range distribution measurements.

Heavy ion activation analysis (HIAA) has been applied to determine the composition of a thin (thickness ∼ 2 μm) Havar foil. The isotopic products from the heavy ion induced nuclear reactions were recoiled out of the thin target foil due to high recoil energy. Depending on their recoil ranges, the products were collected separately in graded thickness of Al catcher foils. Radioactive counting of target and catcher foils was performed with a high resolution γ-spectrometer and quantitative analysis was carried out by comparator method using elemental standard foils.

A high natural radiation zone is investigated for the first time in a geothermal region of Eastern Ghats Mobile Belt (EGMB) of Orissa state in India. The surrounding area comprises a geothermal region which has surveyed using a portable pulsed Geiger–Muller counter. On the basis of findings of GM counter, an area was marked as a high radiation zone. Soil and rock samples collected from the high radiation zone were analyzed by -ray spectrometry (GRS) using NaI(Tl) detector. The radioactivity is found to be contributed mainly by thorium. Concentration of thorium is reported to be very high compared to their normal abundance in crustal rocks. Further, concentrations of 238 U and 40 K are also high compared to normal abundance in crustal rocks but their magnitude is comparatively less than that of thorium. The average concentrations of 238 U (i.e. U( .)), 232 Th and 40 K are found to be 33, 459 ppm and 3%, respectively, in soils and 312, 1723 ppm and 5%, respectively, in the granitic rocks. Maximum concentrations of 238 U, 232 Th and 40 K are found to be 95, 1194 ppm and 4%, respectively, in soils and 1434, 10,590 ppm and 8%, respectively, in the granitic rocks. Radioactive element emits various energies in its decay chain. High energies are utilized to estimate the concentration of actual 238 U, 232 Th and 40 K using a NaI(Tl) detector, however, low energies are used for the same in an HPGe detector. Some of the rock samples (eight in number) were also analyzed using HPGe detector for studying the behavior of low energies emitted in the decay series of uranium and thorium. The absorbed gamma dose rate in air and external annual dose rate of the high radiation zone are calculated to be 2431 nGy/h and 3.0 mSv/y, respectively. It is approximately 10 times greater than the dose rates obtained outside the high radiation zone. The high concentration of uranium and thorium may be one of the possible heat sources together with the normal geothermal gradient for hot springs present in the region. © 2006 Elsevier Ltd. All rights reserved.

Radioactive isotopes 24Na, 34mCl, 65Zn, 69Ge, 71As, 72, 73, 75Se, 77Br, 79Kr, 81Rb, 83Sr, 86Zr and 168Hf with recoil energy ∼3 MeV were implanted in thin film of C60 for the formation of radioactive endohedral fullerenes by recoil implantation technique. The isotopes of interest were produced by 93–120 MeV 16O, 14N beams from Variable Energy Cyclotron Centre, Kolkata. Since direct interaction of primary heavy ion beams with the fullerene film was avoided in our experimental condition, the damage or degradation of the fullerene matrix could be reduced to insignificant level. The endohedral fullerenes formed were separated radio-chemically and the probabilities of formation of radioactive endohedral fullerenes from different isotopes were determined by γ-spectrometry.

Experimental cross sections of a number of reaction channels of 16O ion induced reactions on natural copper target have been determined at different energies in the range of 50–110 MeV of 16O projectile by stacked foil activation technique. The cross sections have been compared with theoretical calculations using the computer code ALICE-91. The experimental values compared reasonably well with the corresponding theoretical estimates. The results indicate no significant role of incomplete fusion process in the 16O induced reactions on natural copper in the energy range of ⩽7 MeV/nucleon. As heavy ion beam produces an extremely narrow layer of activities in the surface of a material, these reactions could be useful for thin layer activation (TLA) study. The purpose of this work is to apply heavy ion activation in TLA technique for the study of surface wear with increased sensitivity.

Excitation functions were measured by stacked-foil activation technique for the $^{150}$Nd(p, xpyn) reaction using 97.65$%$ enriched $^{150}$Nd target. Measurement up to $\sim$50$%$ above barrier and down to 18$%$ below the barrier was performed using proton beam energy (E$_p$) of 7 - 15 MeV from VECC Cyclotron. The yield of suitable $\gamma$ rays emitted following the decay of relevant evaporation residues was determined using a 50$%$ High Purity Germanium (HPGe) detector.(p,n) cross section was found to follow the expected trend with a maximum value of 63.7(4.9)mb at E$_p$ $\sim$ 8.6 MeV. (p,2n) cross section gradually increased with E$_p$ and had maximum contribution to the total reaction cross section after E$_p$ $\sim$ 9.0 MeV. (p, p$^{\prime}$n) reaction channel also showed a reasonable yield with a threshold of E$_p$ $\sim$ 12.0 MeV. The experimental data were corroborated with statistical model calculations using different codes, viz., CASCADE, ALICE/91 and EMPIRE3.1. All the calculations using a suitable set of global parameters could reproduce the excitation function fairly well in the present energy range.

SummaryAdsorption of Zn(II) ions on barium titanate has been studied as a function of concentration of Zn(II) (1.0 ×−5–5.0 × 10−7M), temperature (281–313 K) and pH (4–8) of the adsorptive solution using65Zn tracer and γ-ray spectroscopy. The adsorption process was found to obey the first order rate law and the Freundlich adsorption isotherm for the range of concentration studied. The uptake increases from 32 to 70% with the increase in dilution (from 1.0 × 10−5to 5.0 × 10−7M). The extent of adsorption also increases with increasing temperature and pH of solution. The activation energy for the process was determined to be 12.3 kJ mol−1. The removal of Zn(II) ions by barium titanate appears to be endothermic and irreversible.

A new method for the possible incorporation of nuclear wastes has been attempted here by using ceramic matrix of TiO2 as a host precursor for confinement. Hafnium is used as a simulant for actinide high-level waste. After incorporating 181Hf tracer into TiO2 matrix, the leaching property of the resulting matrix was studied in water, sodium chloride and humic acid solutions. The leaching was measured in each of the case by following the radioactivity of 181Hf. TiO2 matrix has also been exposed to γ-radiation in order to simulate the radiation field for nuclear waste. It has been investigated with a nuclear technique called time differential perturbed Angular Correlation (TDPAC) that the lattice structure of titania remains undisturbed even under a strong radiation field. The leaching of 181Hf has also been studied after irradiating the TiO2 matrix with γ-radiation and the leaching behavior was observed not to change from that before irradiation.

Nurses in many health care settings are likely to encounter a patient with a spinal cord injury (SCI). This is particularly true in the critical care setting where most of these patients first reside soon after hospitalization. SCI effects multiple body systems. The purpose of this article is to present an overview of the nature of SCI with a focus on the physiological and psychosocial alterations that result. Specific medical and nursing care needed to optimize patient outcomes are addressed.

Cross-sections for the reactions 85Rb(α,2n)87Y, 85Rb(α,3n)86Y and 85Rb(α,αn)84Rb have been determined in the α-energy range of 20-50 MeV. Integral recoil ranges of the evaporation residue for the reaction 85Rb(α,αn)84Rb have also been measured. From the recoil range data, the linear momentum transfer to the product nucleus for the above reaction has been deduced. The experimental results are compared with theoretical model predictions. For (α,xn) reactions, the agreement between the theory and the experiment is found to be quite satisfactory. In case of (α,αn) reaction, the theoretical calculations fail to reproduce the experimental cross-sections as well as linear momentum transfer even when the incident α-energy is quite low.

Adsorption of Zn(II) ions on hydrous zirconium oxide was studied as a function of concentration of Zn(II), temperature and pH of the adsorptive solution using 65Zn tracer and high resolution γ -ray spectroscopy. Kinetics of the adsorption for various initial concentration, [C0], of Zn(II) ion was studied. For [C0] ≤ 10-5 M, the adsorption process was found to obey the first order rate law. The activation energy for the adsorption of Zn(II) was determined to be 51.2 kJ/mol. Interaction of Zn2+ ions with the adsorption sites is responsible for the adsorption of Zn(II) on hydrous zirconium oxide.

The electron momentum anisotropy of indium phosphide has been studied by measuring the directional Compton profiles of indium phosphide single crystals with the use of radiation from an 241 Am gamma source. Three different samples, cut along the [100], [110] and [111] planes, were used. The experimental anisotropy has been compared with the results based on the linear combination of Gaussian orbitals (LCGO) method. The agreement is very good with our theoretical results. It is found that the extrema appearing in the dependences on q of the anisotropies have an intimate connection with the bonding properties of the semiconductor. A self-consistent, all-electron, local density calculation for the partial density of states, total density of states and the charge analysis is also presented here.

Independent isomeric yield ratios of 131 Te, 133 T and 134 I hava been determined at five different energies in the range of 25–44 MeV alpha particle induced fission of 238 U using radiochemical and gamma spectrometric techniques. From the independent isomeric yield ratios, fragment angular momenta ( J rms ) have been deduced using a statistical model analysis. The J rms were also calculated theoretically based on thermal equilibration of various collective modes after considering the occurrence of multichance fission. These data and the literature data for various fragments in the mass region 126–136 in 238 U(α,f), 238 U(p,f) and 238 U(γ,f) show the following important features: (i) Both the entrance channel excitation energy and input angular momentum affect the fragment angular momentum in the exit channel. (ii) There are two groups of fission products from the point of view of change of fragment angular momentum with increase in excitation energy and input angular momentum. (iii) Fragment angular momentum depends on nuclear structure effect such as shell closure proximity and odd-even effect. (iv) The fragment angular momentum calculated theoretically based on statistical equilibration of various collective modes are in good agreement with the experimental values indicating the validity of such an assumption.

In this paper we report the measurement of the Compton profile of polycrystalline scandium oxide using 59.54 keV gamma radiation from a Am 241 source. The experimental results are compared with the theoretical Compton profile values calculated based on the linear combination of Gaussian orbital (LCGO) method. The theoretical values from such calculations agree well with the experimental results.

The absorption behavior of Te and Sb in different oxidation states by anion exchange resins in hydrochloric acid medium has been studied. Distribution coefficients for Te(IV), Te(VI) as a function of HCl acid concentration (upto 3M HCl) have been determined. The absorbability for Sb(III) was noticed to be very high and could not be eluted out of the column using HCl as eluent. Sb(V) could be eluted quantitatively using 3M HCl. The present study clearly indicate that due to the EC/β+ decay of the parent isotopes117,118Te, the daughter nuclei117,118Sb are produced predominantly as Sb(III).

High spin states of nuclei in the vicinity of neutron shell closure N = 82 and proton shell closure Z = 82 have been studied using the Clovere Ge detectors of Indian National Gamma Array. The shape driving effects of proton and neutron unique parity intruder orbitals for the structure of nuclei around the above shell closures have been investigated using light and heavy ion beams. Lifetime measurements of excited states in 139Pr have been done using pulsed-beam-γ coincidence technique. The prompt spectroscopy of 207Rn has been extended beyond the 181μs 13/2+ isomer. Neutron-rich nuclei around 132Sn have been produced from proton induced fission of 235U and lifetime measurement of low-lying states of odd-odd 132I have been performed from offline decay.

Experiment has been performed to explore the complete and incomplete fusion dynamics in heavy ion collisions using stacked foil activation technique. The measurement of excitation functions of the evaporation residues produced in the 20Ne+165Ho system at projectile energies ranges ≈ 4-8 MeV/nucleon have been done. Measured cumulative and direct cross-sections have been compared with the theoretical model code PACE-2, which takes into account only the complete fusion process. The analysis indicates the presence of contributions from incomplete fusion processes in some α-emission channels following the break-up of the projectile 20Ne in the nuclear field of the target nucleus 165Ho.

The information of ICF reaction has been obtained from the measurement of excitation function (EF) of ERs populated in the interaction of 20Ne & 16O on 55Mn, 159Tb & 156Gd targets. Sizable enhancement in the measured cross-sections has been observed in α-emitting channels over theoretical predictions, which has been attributed to ICF of the projectile. In order to confirm the findings of the measurements and analysis of EFs, the forward recoil range distributions of ERs populated in 20Ne+159Tb (E ∼165MeV) and 16O+156Gd (E ∼ 72, 82 & 93MeV) systems, have been measured. It has been observed that peaks appearing at different cumulative thicknesses in the stopping medium are related with different degree of linear momentum transfer from projectile to target nucleus by adopting the break-up fusion model consideration. In order to deduce the angular momentum involved in various CF and / or ICF reaction products, spin distribution and side-feeding intensity profiles of radio-nuclides populated via CF and ICF cha...

Integral recoil ranges of evaporation residues for the reactions 107Ag(α, 3n), 107Ag(α, α2n), 109Ag(α, 2n), 109Ag(α, 3n), 109Ag(α, 4n), 115In(α, 2n), 115In(α, 3n) and 115In(α, αn) have been measured in the energy range of 202 - 60 MeV α-particles using the conventional thick target thick catcher technique. Transfer of linear momenta to the product nuclei for the above reactions have been deduced from experimental recoil range data. Detailed comparisons of the observations with predictions of theoretical calculations based on statistical model are presented and discussed. For (α, xn) reactions, overall agreement between the theory and the experiment is found to be satisfactory specially at low projectile energy. In cases of (α, αxn) reactions, the theory failed to reproduce the experimental linear momentum transfer even at low incident alpha energy.

Electron capture (EC) decay of ${}^{146}$Gd (${t}_{\frac{1}{2}}=48$ d) to the low lying states of ${}^{146}$Eu has been studied using high-resolution $\ensuremath{\gamma}$-ray spectroscopy. The ${}^{146}$Gd activity was produced by ($\ensuremath{\alpha},2n$) reaction at ${E}_{\ensuremath{\alpha}}=32$ MeV using a 93.8$%$ enriched ${}^{144}$Sm target. The level structure has been considerably modified from the measurement of $\ensuremath{\gamma}$-ray singles, $\ensuremath{\gamma}\ensuremath{\gamma}$ coincidences and decay half lives. Lifetime measurement has been performed for the 3${}^{\ensuremath{-}}$ (114.06 keV) and 2${}^{\ensuremath{-}}$ (229.4 keV) levels of ${}^{146}$Eu using the mirror symmetric centroid difference (MSCD) method with LaBr${}_{3}$ (Ce) detectors. The lifetimes for these two states have been found to be 5.38 $\ifmmode\pm\else\textpm\fi{}$ 2.36 ps and 8.38 $\ifmmode\pm\else\textpm\fi{}$ 2.19 ps respectively. Shell model calculation has been performed using oxbash code in order to interpret the results.

A radiochemical procedure for the separation of carrier-free 111 In from an Ag matrix is described. 111 In is produced by the bombardment of a natural Ag target by α-particles. The method involves the removal of bulk silver by chloride precipitation followed by anion exchange separation of the 111 In from the trace amount of Ag still present after chloride precipitation.

This study was undertaken to determine differences between caloric intake and requirements of critically ill, enterally fed, neurosurgical and neurotrauma patients and to determine the nature and frequency of interruptions in enteral feedings in this same population. This descriptive, prospective study was conducted in a surgical intensive care unit (ICU) in a university teaching hospital. The sample consisted of 52 mechanically ventilated, critically ill patients with a mean age of 48.96 years who were receiving enteral nutrition for at least two days. Basal energy requirements, daily nutritional intake and enteral feeding interruption characteristics were recorded for a total of 586 study days. Underfeeding due to interruptions occurred in the majority of patients for the first eight days following initiation of enteral feeding. Reasons for underfeeding were interruptions of continuous tube feedings due to medication administration via the feeding tube (31%), feeding tube displacement (27%), surgery (12%), ileus (9%), radiologic studies (9%), airway management (8%), bedside procedures (3%) and agitation (1%). The frequency of these enteral feeding interruptions may indicate inadequate nutritional support, highlighting the importance of performing daily nutritional monitoring to prevent malnutrition.

A method for the separation of carrier-free vanadium from scandium and bulk amount of titanium has been developed. Vanadium has been produced through the reactionnatTi(d,n)48,49V with 8 MeV deuterons from the Variable Energy Cyclotron, Calcutta. The separation is performed with Dowex 1×8, 50–100 mesh fluoride from anion exchange resin which retains all the scandium and titanium with 4.5M hydrofluoric acid as eluent, while vanadium(V) is easily eluted. The chemical yield of vanadium was >85%.

Incomplete fusion of {sup 20}Ne with {sup 59}Co has been investigated at 3-7 MeV/nucleon using the measurement and analysis of excitation functions. The recoil-catcher technique followed by offline gamma-ray spectroscopy has been employed. Evaporation residues are found to have contributions from precursor decays, which have been separated out from the measured cumulative cross sections of evaporation residues. Measured independent cross sections are compared with PACE-2 predictions. The PACE-2 calculations are carried out for evaporation residues formed in complete fusion (CF), and the parameters are optimized so as to reproduce the cross section of evaporation residues produced exclusively in CF, e.g., xn and pxn products. With these parameters, the predicted CF cross sections for alpha emission products are calculated. Any substantial enhancement in the experimental cross section over the PACE-2 prediction is taken as a signature of incomplete fusion (ICF). The analysis indicates the occurrence of incomplete fusion involving the breakup of {sup 20}Ne into {sup 16}O + {sup 4}He and/or {sup 12}C + {sup 8}Be(2{alpha}) followed by fusion of one of the fragments with the target nucleus {sup 59}Co. These data also suggest that the probability of incomplete fusion increases with the projectile energy. Moreover, the ICF probability is foundmore » to increase with entrance-channel mass-asymmetry of the projectile-target systems.« less

The alpha and EC decay of 208Po have been studied. The K-capture probability and the (L+M+. . .)/K capture ratio to the 925 keV level, a second forbidden nonunique transition, in the decay of 208Po have been deduced from the measurement of K X-rays and gamma -rays depopulating the 925 keV level in 208Bi. The experimental value is compared with the theoretical estimate using the theory of Behrens and Buhring (1971). A significant contribution of capture from higher shells is observed.

Isomeric yield ratios for the reactions {sup 107}Ag({alpha},3{ital n}){sup 108}In, {sup 107}Ag({alpha},{alpha}3{ital n}){sup 104}Ag, {sup 109}Ag({alpha},2{ital n}){sup 111}In, and {sup 109}Ag({alpha},3{ital n}){sup 110}In are determined in the energy range of 20--63 MeV {alpha} particles. Excitation functions for the above reactions as well as for the {sup 107}Ag({alpha},2{ital n}){sup 109}In, {sup 107}Ag({alpha},{alpha}2{ital n}){sup 105}Ag, {sup 109}Ag({alpha},4{ital n}){sup 109}In, {sup 109}Ag({alpha},5{ital n}){sup 108}In, and {sup 109}Ag({alpha},{alpha}4{ital n}){sup 105}Ag reactions are also presented. Experimental excitation functions are compared with statistical model calculations taking into account precompound particle emission. Isomeric yield ratios are found to depend strongly on the root mean square orbital angular momentum in the entrance channel. A semiempirical method for the prediction of isomeric yield ratios failed to reproduce experimental data even for compoundlike reactions. Isomeric yield ratios were also calculated in the frame of a statistical model under consideration of angular momentum effects in the preequilibrium and the equilibrium stage. Overall agreement between the theory and the experiment for isomeric yield ratios was found to be satisfactory especially at low bombarding energy when compound nucleus reaction channel is dominant. The discrepancy observed at higher bombarding energies needs to be theoretically investigated in greater detail.