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Pahardia-Rungikocha area lies at the south-western end of the north Singhbhum mobile belt (NSMB). The terrain of NSMB is known for gold occurrences. Systematic exploration by the authors have established significant resource (0.48 million tonnes) with appreciable grade (3.43 g/t) of gold, for the first time. This has added to the National Mineral Inventory on gold and the area has now been granted mining lease. [ABSTRACT FROM AUTHOR]

The Palaeoproterozoic eastern Mahakoshal belt of Central India Tectonic Zone (CITZ) is known for gold occurrences. Gold occurs predominantly in quartz veins and quartz-carbonate veins. It is associated with pyrite, pyrrhotite and arsenopyrite mineral assemblages. The secondary alteration products such as 'scorodite' and 'mansfieldite' are also associated with gold mineralisation. Recent investigations carried out in Parsoi area, have indicated the association of gold with bismuth, bismuthinite and telluride. This is the first record of bismuth from the Mahakoshal belt. The studies of the bismuth tellurides contribute to the assessment and evaluation of concentrations of gold resources. [ABSTRACT FROM AUTHOR]

In the present study, atomic layer deposition has been used to grow a series of Ti incorporated ZnO thin films by vertically stacking different numbers (n = 1-7) of ZnO/TiOx layers on (0001) sapphire substrates. The effects of defect states mediated chemisorption of O2 and/OH groups on the electrical properties of these films have been investigated by illuminating the samples under UV light inside a high vacuum optical cryostat. The ultra-thin film having one stacked layer (n = 1) did not show any change in its electrical resistance upon UV light exposure. On the contrary, marginal drop in the electrical resistivity was measured for the samples with n ≥ 3. Most surprisingly, the sample with n = 2 (thickness ~ 12 nm) showed an insulator to metal transition upon UV light exposure. The temperature dependent electrical resistivity measurement on the as grown film (n = 2) showed insulating behaviour, i.e., diverging resistivity on extrapolation to T→ 0 K. However, upon UV light exposure, it transformed to a metallic state, i.e., finite resistivity at T → 0 K. Such an insulator-metal transition plausibly arises due to the de-trapping of conduction electrons from the surface defect sites which resulted in an upward shift of the Fermi level above the mobility edge. The low-temperature electron transport properties on the insulating film (n = 2) were investigated by a combined study of zero field electrical resistivity ρ(T) and magneto-resistance (MR) measurements. The observed negative MR was found to be in good agreement with the magnetic field induced suppression of quantum interference between forward-going paths of tunnelling electrons. Both ρ(T) and MR measurements provided strong evidence for the Efros-Shklovskii type variable range hopping conduction in the low-temperature (≤40 K) regime. Such studies on electron transport in ultra-thin n-type doped ZnO films are crucial to achieve optimum functionality with long term reliability of ZnO based transparent conducting oxides. [ABSTRACT FROM AUTHOR]

Gold exploration in the Mahakoshal belt has been carried out for the past thirty years and mostly quartz veins were identified as the host targets. The recent study based on the concept of mineral system has indicated that gold occurs in mafic and ultramafic rocks also, besides the quartz veins. The mineralisation in Agori Formation is generally confined to Algoma type BIF, metavolcanics and phyllites, while in Parsoi Formation it occurs predominantly in quartz veins. The metavolcanics have acted as source rocks and the crustal deep faults have acted as conduits for mineralizing fluids, in the continental back arc type tectonic setting with two mineral systems viz. (i) basin related fluid flow with active magmatism, and (ii) magmatic related hydrothermal system. [ABSTRACT FROM AUTHOR]

MgZnO/ZnO bilayers (Mg concentration of ∼30%) have been grown and subsequently annealed at different temperatures in the range of 600-900 °C with the specific interest of studying the effect of inter-diffusion of Mg on the photoluminescence (PL) properties of the bilayers. The influence of Mg diffusion and material homogenization is evaluated through absorption, PL, and secondary ion mass spectrometry (SIMS) measurements. No appreciable change in the spectral positions is seen either in PL or absorption up to an annealing temperature of 700 °C, which is also supported by SIMS. However at higher annealing temperatures, diffusion of Mg into the ZnO layer is clearly evident in SIMS profile, which results in the red-shift (blue-shift) of spectral positions of MgZnO (ZnO) layer, respectively. Finally, for the sample annealed at 900 °C, the two layers are completely merged providing a single peak at ∼3.60 eV in PL/absorption corresponding to a completely homogenized MgZnO layer. Spectroscopic results are corroborated by the numerical simulations based on a simple theoretical model, which correlates the observed PL spectra of the heterostructures with the experimental Mg diffusion profiles across the heterointerface, as measured by SIMS. [ABSTRACT FROM AUTHOR]

For a detailed study on the semiconductor to metal transition (SMT) in ZnO thin films doped with Al in the concentration range from 0.02% to 2%, we grew these films on (0001) sapphire substrates using sequential pulsed laser deposition. It was found that the Al concentration in the films increased monotonically with the ratio of ablation durations of the alumina and ZnO targets used during the deposition. Using x-ray photo electron spectroscopy, it was found that while most of the Al atoms occupy the Zn sites in the ZnO lattice, a small fraction of the Al also gets into the grain boundaries present in the films. The observed SMT temperature decreased from ∼270 to ∼50 K with increase in the Al concentration from 0.02% to 0.25%. In the Al concentration range of ∼0.5% to 2%, these doped ZnO films showed metallic behavior at all the temperatures without undergoing any SMT. A theoretical model based on thermal activation of electrons and electron scatterings due to the grain boundaries, ionic impurities, and phonons has been developed to explain the observed concentration and temperature dependent SMT. [ABSTRACT FROM AUTHOR]

Zero kinetic energy (ZEKE) photoelectron spectroscopy of the hydroquinone-water (HQW) complex was carried out to characterize its S1-S0 resonantly enhanced multiphoton ionization (REMPI) spectrum in terms of the cis and trans conformers. The ZEKE spectra of the hydroquinone isomers show differences in the Franck-Condon (FC) activity of a few ring modes, viz., modes 15, 9b, and 6b, due to the different symmetries of the two isomers. These modes were used as a “diagnostic tool” to carry out the categorical assignment of the REMPI spectrum of the HQW complex. It was found that the FC activity of these diagnostic modes in the cationic ground state (D0) of the water complex is similar as that of the monomer. The two lowest energy transitions in the REMPI spectrum of the water complex, 33 175 and 33 209 cm-1, were reassigned as the band origins of the cis and trans hydroquinone-water complexes, which is opposite of the previous assignment. The intermolecular stretching mode (σ) of the complex shows a long progression, up to v′=4, in the cationic ground state and is strongly coupled to other observed ring modes. The Franck-Condon factors for different members in the progression were calculated using the potential energy surfaces computed ab initio. These agree well with the observed intensity patterns in the progression. The ionization potential of the trans and cis complexes was determined to be 60 071±4 and 60 024±4 cm-1, respectively. [ABSTRACT FROM AUTHOR]

Introduction: Body adiposity measured by percentage of body fat (BF%) is found to be better predictor of cardiovascular morbidity and mortality than body mass index (BMI). Limited information exists showing relationship between BMI and BF% in North Indian population. Objectives: To study the relationship between BMI and BF% among North Indian adult females across various age strata and level of BMI. Materials and Methods: This was a cross-sectional study conducted at Ballabgarh Health and Demographic Surveillance Site (HDSS) among randomly selected females. BMI using standard techniques and BF% using bioelectrical impedance analysis was estimated. Linear regression was performed using general linear model with BF% as dependent variable and BMI as main independent variable. Results: Mean (±2 SD) age of participants was 41.3 ± 15.7 years. Mean BMI (±SD) was 23.3 (±4.6) kg/m2, whereas mean fat mass (±2 SD) and BF% (±95% CI) was 19.2 (±7.9) kg and 33.6 (±6.9) %. BMI and BF% were highly correlated among obese (r = 0.77), whereas least correlated (r = 0.32) in underweight females. Across age strata, correlation between BMI and BF% was maximum in 18–35 years age group (r = 0.95), whereas least in females ≥56 years (r = 0.67). Age and BMI together predicted 73% of variability in BF% in hierarchical linear regression model. Conclusions: In this population, we have found strong correlation between BMI and BF% particularly at higher level of BMI and in younger females. There is need to conduct more robust prospective longitudinal studies to assess BF%, which is a better predictor of cardiovascular morbidity and mortality. [ABSTRACT FROM AUTHOR]

Summary: Visceral leishmaniasis (VL) is a disseminated and lethal disease of reticulo‐endothelial system caused by protozoan parasites Leishmania donovani and L. infantum, which are known to induce host T cell suppression. To understand the impact of parasite load on T cell function, the present was focused on parasite load with T cell function in bone marrow of 26 VL patients. We observed significant enrichment of forkhead box protein 3 (FoxP3)+ (P = 0·0003) and interleukin (IL)‐10+ FoxP3+ regulatory T cells (Treg) (P = 0·004) in the bone marrow (BM) of patients with high parasite load (HPL) compared with low parasite load (LPL). Concordantly, T effector cells producing interferon (IFN)‐γ (P = 0·005) and IL‐17A (P = 0·002) were reduced in the BM of HPL. Blocking of Treg‐cell derived suppressive cytokines [(IL‐10 and transforming growth factor (TGF)‐β] rescued the effector T cells and their functions. However, it was observed that TGF‐β levels were dominant, favouring Treg cell differentiation. Furthermore, the low ratio of IL‐6/TGF‐β favours the suppressive milieu in HPL patients. Here we show the change in levels of various cytokines with the parasitic load during active VL, which could be helpful in devising newer immunotherapeutic strategies against this disease. [ABSTRACT FROM AUTHOR]

Electron interference effects and transition from weakly localized to a strongly localized transport regime is observed in Cu doped ZnO thin films grown by pulsed laser deposition on c-sapphire substrates. The doping concentration of Cu was varied from 0% to 10%. Up to the doping concentration of ~ 0.5%, the films showed weakly localized behavior where quantum corrections to conductivity due to electron interference was active. At these doping concentrations, a transition from 3D to 2D weak localization was also observed as the measurement temperature was decreased. But at Cu concentrations of 5% and beyond, the films were found to show behavior of strong localization where the transport at low temperature was dominated by hopping mechanism. [ABSTRACT FROM AUTHOR]

n -ZnO/p-Si heterojunctions were grown by atomic layer deposition (ALD) on (100) p-Si substrates at different growth temperatures in the range of ~100–250 °C. The current-voltage characterization of all the heterojunctions showed typical rectifying behavior, a true signature of a p-n junction diode. The diode grown at 100 °C were having significantly lower reverse saturation current (~21 nA) and high rectification factor (~120) compared to those grown at relatively higher temperatures such as 200 or 250 °C. From capacitance-voltage measurements, it was found that the depletion width in the ZnO side of n -ZnO/p-Si diode was maximum (~60 nm) for the diode grown at 100 °C and decreased gradually to ~3 nm for the diodes grown at high temperatures of 250 °C. The electron concentration in ZnO films was found to increase significantly on increasing the growth temperature from ~100 to 250 °C. The junction capacitance also showed an increasing trend with increase in the growth temperature. The variation of diode parameters with growth temperature has been discussed in terms of carrier concentration in ZnO films and associated growth mechanisms of the ALD. Such low temperature grown n -ZnO/p-Si diodes with lower reverse saturation current and large depletion width may be suitable for photo detection applications. [ABSTRACT FROM AUTHOR]

The extractions of potassium value from feldspar via roasting and leaching route was studied with a focus on the effects of the roasting time, temperature, additives, and particle size. Sodium chloride and phosphogypsum (PG) were used as a source of chloride and calcium, respectively, and played the important role during the roasting of feldspar. When the feldspar sample was roasted at 900°C with sodium chloride alone, the extraction of potassium was limited to 61%. The extraction could go up to 92.5% by the addition of phosphogypsum along with sodium chloride. The optimum conditions of potassium extraction were found to be, particle size 100 µm, roasting temperature 900°C and roasting time of one hour. The X-ray diffraction study indicated the formation of sylvite (KCl) in the roasted product and its disappearance in roast-leach residue due to its high water solubility. The morphological changes during the roasting process were clearly observed by field emission scanning electron microscope (FESEM) images. The extraction of potassium from feldspar was best fitted by the Ginstling and Brounshtein kinetic model. The activation energy of 238.6 KJ/mole and 28.73 KJ/mole for low and high-temperature regions indicated that the overall extraction process follows two-steps reaction path. [ABSTRACT FROM PUBLISHER]

We report on the dimensional crossover of electron weak localization in ZnO/TiOxstacked layers having well-defined and spatially-localized Ti dopant profiles along film thickness. These films were grown by in situ incorporation of sub-monolayer TiOx on the growing ZnO film surface and subsequent overgrowth of thin conducting ZnO spacer layer using atomic layer deposition. Film thickness was varied in the range of ~6-65 nm by vertically stacking different numbers (n=1-7) of ZnO/TiOx layers of nearly identical dopant-profiles. The evolution of zero-field sheet resistance (R〉) versus temperature with decreasing film thickness showed a metal to insulator transition. On the metallic side of the metal-insulator transition, R〉 (T) and magnetoresistance data were found to be well corroborated with the theoretical framework of electron weak localization in the diffusive transport regime. The temperature dependence of both R〉 and inelastic scattering length provided strong evidence for a smooth crossover from 2D to 3D weak localization behaviour. Results of this study provide deeper insight into the electron transport in low-dimensional n-type ZnO/TiOx stacked layers which have potential applications in the field of transparent oxide electronics. [ABSTRACT FROM AUTHOR]

Dopant-profile independent electron transport has been observed through a combined study of temperature dependent electrical resistivity and magnetoresistance measurements on a series of Ti incorporated ZnO thin films with varying degree of static-disorder. These films were grown by atomic layer deposition through in-situ vertical stacking of multiple sub-monolayers of TiOx in ZnO. Upon decreasing ZnO spacer layer thickness, electron transport smoothly evolved from a good metallic to an incipient non-metallic regime due to the intricate interplay of screening of spatial potential fluctuations and strength of static-disorder in the films. Temperature dependent phase-coherence length as extracted from the magnetotransport measurement revealed insignificant role of inter sub-monolayer scattering as an additional channel for electron dephasing, indicating that films were homogeneously disordered three-dimensional electronic systems irrespective of their dopant-profiles. Results of this study are worthy enough for both fundamental physics perspective and efficient applications of multi-stacked ZnO/TiOx structures in the emerging field of transparent oxide electronics. [ABSTRACT FROM AUTHOR]

We report the effects of electron interference on temperature dependent transport properties of two dimensional electron gas (2DEG) confined at the interface in polycrystalline MgZnO/ZnO heterostructures grown by pulsed laser deposition on c-alumina substrates. On increasing Mg concentration in the MgZnO layer, the sheet electron concentration was found to increase and the sheet resistance was found to decrease. In addition, the electron concentration and mobility were almost temperature independent in the range from 4.2 to 300 K, indicating the formation of 2DEG at the interface. The temperature dependent resistivity measurements showed a negative temperature coefficient of resistivity at low temperatures together with negative magnetoresistance. These were found to be caused by electron interference effects, and the experimental data could be explained using the models of quantum corrections to conductivity. [ABSTRACT FROM AUTHOR]

The expression for the critical Reynolds number Rc derived by Misra [Phys. Essays 25, 532 (2012)] is compared with experimental data. It is found that the ratio Rc / ( ν / α ) is approximately constant ~0.21 with a range, 0.16-0.26 for gases, and varies between 2 and 5 for liquids. Here, ν is the kinematic viscosity and α = ħ / 2 m0 , where and m 0 are, respectively, the reduced Planck’s constant and the mass of an individual molecule of the fluid. The large difference between the gas and liquid values for Rc / ( ν / α ) is explained by the difference between the molecular separation lengths between gases and liquids. [ABSTRACT FROM AUTHOR]

Welwitschia mirabilis is a phylogenetically important primitive gymnosperm of the monogeneric family Welwitschiaceae. The plant is unique in appearance, having only two leaves throughout its life span. It is a long-lived, slow growing plant and could prove as an excellent experimental material for the study of antiageing gene. Because of non-availability of plant material and the intractable nature of the plant, limited tissue culture work has been conducted. In the present study, callus was induced from mature leaf-tip explants from a 26-year-old plant. The induced callus grows at a comparatively faster pace. Although successful induction of organized shiny and smooth, globular structures were observed, no shoots had developed in the callus. [ABSTRACT FROM AUTHOR]

A clear signature of disorder induced quantum-interference phenomena leading to phase-coherent electron transport was observed in (Zn, Al)Ox thin films grown by atomic layer deposition. The degree of static-disorder was tuned by varying the Al concentration through periodic incorporation of Al2O3 sub-monolayer in ZnO. All the films showed small negative magnetoresistance due to magnetic field suppressed weak-localization effect. The temperature dependence of phase-coherence length (lφ ∝ T-3/4 ), as extracted from the magnetoresistance measurements, indicated electron-electron scattering as the dominant dephasing mechanism. The persistence of quantum-interference at relatively higher temperatures up to 200 K is promising for the realization of ZnO based phase-coherent electron transport devices. [ABSTRACT FROM AUTHOR]

Tunnel magnetoresistance in Sr2FeMoO6based tri-layered structure was studied at room temperature. The Sr2FeMoO6/SrTiO3/Sr2FeMoO6tri-layered structure was grown by pulse laser deposition on STO buffered Si(100) substrate. The X-ray diffraction and Micro Raman studies confirm the polycrystalline phase formation of SFMO thin films without any impurity phases. The single layer SFMO thin film shows the good ferromagnetic behavior with saturation magnetization of ∼1.48 μB/ f.u. at room temperature. The high value of tunneling magnetoresistance of ∼7% of tri-layer structure at room temperature was attributed to spin dependent tunneling through uniform STO barrier layer. The room temperature tunneling magnetoresistance in SFMO tri-layer structure open the future prospect for their possible integration to room temperature spintronic devices. [ABSTRACT FROM AUTHOR]

The article focuses on the gold associated with copper mineralization in Garhwal Lesser Himalaya, Rudraprayag district in Uttarakhand, India. It mentions chlorite schist associated with quartzite of Berinag Formation is exposed around Rudraprayag town in the Mandakini River valley and dolomite is intruded by thin quartz–carbonate veins. It also mentions higher values of gold are associated with the concentration of sulphides.

Aims: To assess seroprevalence of HIV among antenatal women and the extent of utilization of interventions to minimize the risk of mother-to-child transmission. Study Design: Descriptive cross-sectional study was carried out among antenatal women who attended integrated counseling and testing center (ICTC) of HIV. Sample sizes were determined from the number of pregnant women that attended ICTC. Place and Duration of Study: Data and samples were collected from a tertiary care hospital, Odisha, India during January 2009 to December 2012. Methodology: All pregnant women were counseled and tested for HIV by rapid test. All HIV-seropositive antenatal women (ANW) were linked to services and followed-up for institutional delivery, single-dose nevirapine (sdNVP) prophylaxis, infant feeding options and testing of children at 18 months. Results: Out of 11,508 ANW registered and pretest counseled, 11,390 (98.97%) accepted HIV testing. Sixty women were found to be seropositive, thus showed seroprevalence rate of 0.53% (60/11,390). CD4 testing was carried out in all ANW and five (8.33%) were eligible for antiretroviral therapy (ART). Seven (11.67%) had opted for medical termination of pregnancy (MTP). All 48 ANW delivered institutionally, only 7 (14.58%) received cesarean delivery. Out of 46 live births, 5 (10.87%) ANW were on ART, 35/41 (85.37%) received sdNVP mother baby-pair prophylaxis and only 8/46 (17.39%) mother opted for replacement feeding. Twenty one children have reached 18 months till date and among them three (14.29%) were HIV-seropositive. All three were delivered vaginally, received sdNVP prophylaxis and were exclusively breast fed for 6 months. Conclusion: The HIV-seroprevalence rate among antenatal women was 0.53% and mother-to-child transmission (MTCT) rate was 14.29%. Reduction in MTCT rate needs pre or early antenatal HIV testing, prenatal antiretroviral medication, preference for cesarean delivery, 100% antiretroviral prophylaxis coverage and education on avoidance of breast feeding. [ABSTRACT FROM AUTHOR]

It was found that by changing the substrate temperature from room temperature to ∼850 °C, ZnO thin films with widely varying resistivity values could be grown on sapphire substrates using DC-discharge-assisted pulsed laser deposition (PLD) in oxygen ambient. The resistivity of the film grown at room temperature was too high to measure using our existing setup. However, as the growth temperature was increased from 550 °C to 750 °C, the resistivity first decreased slowly from ∼14.0 to 4.4 Ω m and then dropped suddenly to get saturated at ∼2.0×10 Ω m as the growth temperature was further increased. In contrast to these, when there was no DC-discharge, the variation of resistivity for ZnO thin films grown by PLD was marginal up to the substrate temperature of ∼850 °C. The reason for these observations was found to be the combined effects of reduction in donor defect densities like oxygen vacancies and zinc interstitials, introduction of acceptor type defects like interstitial oxygen and zinc vacancies, and the resultant poor carrier mobility at lower growth temperatures. At higher growth temperatures (800 °C and above), the appearance of oxygen vacancies and increase in mobility due to better crystalline quality were found to be responsible for reducing the resistivity. The PL of these films had significant emission in the green and red regions of the spectrum due to the aforesaid defect related transitions. Such highly resistive and luminescent films might be suited for applications such as resistive RAM, UV-photo detector, TFT, piezoelectric, transparent phosphor, and broadband LED applications. [ABSTRACT FROM AUTHOR]

Abstract: Polycrystalline Sr2FeMoO6 (SFMO) thin films were deposited at different substrate temperatures (500–800°C) on STO buffered Si (100) substrates by pulsed laser deposition (PLD). Structural analysis shows the single phase formation of polycrystalline SFMO thin films. A large (~12%) high field magnetoresistance (HFMR) was observed at 5K in polycrystalline films deposited at 800°C.. First time, we studied the MR effect in polycrystalline SFMO thin films grown on Si substrate, which make them very promising for magnetoresistive and spintronic applications and possibly open the future prospect for their possible integration in microelectronic industries. [Copyright &y& Elsevier]

We report the room temperature magnetoresistance in Sr2FeMoO6 based magnetic tunnel junctions (MTJs). The micrometre-sized (SFMO/STO/SFMO) devices were grown by pulse laser deposition. The crystal structure and phase purity of SFMO layers were examined by X-ray diffraction, which shows the single phase formation of ordered polycrystalline SFMO thin film without any impurity phases. The FESEM micrograph clearly shows the presence of an ultrathin STO barrier layer. The magnetization measurements show the good ferromagnetic loop behaviour and Curie temperature (TC) well above 375 K, which indicate fairly high-quality growth of SFMO thin films. The current–voltage curve of the MTJ devices at room temperature exhibited nonlinear and asymmetric behaviour in agreement with the predictions of tunnel conductance. The observed large tunnelling magnetoresistance (TMR ∼ 7%) at room temperature was attributed to spin-dependent tunnelling across a uniform ultrathin STO tunnel barrier sandwiched between two identical SFMO (bottom and top) electrodes in MTJ devices. [ABSTRACT FROM AUTHOR]

Planar metal-insulator-metal (MIM) mono-dielectric layer stacks were fabricated using pulsed laser deposited thin films of high-k dielectric LaGdO3. These stacks showed high capacitance density ∼43.5 fF/μm2 with sub-nanometer capacitance equivalent thicknesses of ∼0.66 nm, large breakdown field of ∼6 MV/cm, greater energy storage density of ∼40 J/cm3, smaller voltage coefficient of capacitance, and lower dependence of it on layer thickness α ∝ d-1 and frequency. All these features make LaGdO3 a material of interest for next generation MIM structures for radio frequency, analog/mixed-signal, and dynamic random access memory applications. [ABSTRACT FROM AUTHOR]

Careful selection of pulsed laser deposition conditions was executed to achieve sub-nanometer EOT (equivalent oxide thickness) in amorphous LaGdO3 based high-k/metal gate stacks. The lowest EOTs attained were ∼5.4 Å and 8.4 Å with and without quantum mechanical correction, respectively. The electrical measurements yielded a high permittivity of 20.5 ± 2.4, a thin bottom interfacial layer of thickness 4.5 ± 1 Å, and interface (cm-2 eV-1) and fixed (cm-2) charge densities of ∼1012. Analysis of temperature dependent leakage currents revealed that gate injection current was dominated by Schottky emission below 1.2 MV/cm and quantum mechanical tunneling above this field. The physical origin of substrate injection was found to be a combination of Schottky emission and trap assisted tunneling. [ABSTRACT FROM AUTHOR]

When a molecule is described as an energy continuum following the author's definition of rigid body motion [P. K. Misra, Phys. Essays 22, 478 (2009)], the pressure field inside a fluid is determined to consist of two components: one resulting from the aggregate transfer of momentum of all molecules in random motion and the second from the aggregate of the pressure distributions inside the energy continuum of each molecule. The first pressure component is the mean pressure field inside the fluid, whereas the second pressure component appears as a random perturbation to the mean pressure. Under some conditions of fluid flow, the perturbation pressure causes the flow to become unstable as originally observed by Reynolds. For flows with no external disturbances, the criterion for flow instability is determined to be Re≻[2vm0/h]c, where Re is the Reynolds number, v is the kinematic viscosity for the fluid, m0 the rest mass of the fluid molecule, h the reduced Planck's constant, and ca function of the flow parameters and the level of external disturbances to the flow. For air, one has 2vm0/h≈1.4 X 104. This is comparable to the critical Reynolds number originally proposed by Reynolds; however, the observed value of the critical Reynolds number will depend on the value of c. [ABSTRACT FROM AUTHOR]

The Quaternary sediments of the Aramda Reef Member of the Chaya Formation exposed in the Mojap coast near Mithapur, Gujarat are characterized by well-developed coralline algal build-ups. These algal build-ups are exceptionally rich in coralline algae and corals. In the present paper, thirteen species belonging to eight genera of coralline algae are described. Out of these, seven species ( Titanoderma nataliae, Lithophyllum nitorum, Lithophyllum quadratum, Spongites sp. Brandano et al., 2005, Sporolithon lvovicum, Mesophyllum fructiferum and Lithothamnion praefruticulosum) are the new records for India. Four species ( Titanoderma pustulatum, Sporolithon intermedium, Mesophyllum commune and Phymatolithon sp.) are first time recorded from the study area. Among the major framework builders of coralline algae of the Aramda Reef Member are Lithophyllum, Titanoderma, Sporolithon, Mesophyllum and Lithothamnion. Two associations of the coralline algal assemblages can be distinguished: one indicating shallow water, high-energy conditions is developed in the upper part, while the other suggesting deposition in low-energy conditions is characteristic of the lower part of the succession. These algal associations, together with their growth-forms (encrusting, warty to fruticose, layered) come from stratigraphically separate beds. They indicate that the temperature, depth and hydrodynamic energy conditions also fluctuated during deposition of the Aramda Reef Member. It is concluded that the lower Hapalidiaceae-Sporolithaceae association dominated during warmer interval, whereas the upper lithophylloids association flourished in relatively low-temperature conditions. The associated corals indicate that minimum winter sea surface temperature remained above 18°-20° C. [ABSTRACT FROM AUTHOR]

The wave-particle duality of the photon is explained by the author's [P. K. Misra, Phys. Essays 22, 478 (2009)] postulate that a particle is an energy distribution in space, the total energy being the mass-equivalent energy of the particle. The reverse situation is where a distribution of energy in space moves as whole with respect to an observer and it behaves as a particle. In this paper a photon is described as an electromagnetic energy packet with a distribution in space released during the transition of an electron from a higher-energy to lower-energy orbit inside the atom. The photon motion follows both the author's equations of motion of a particle and Maxwell's equations for electromagnetism. The equivalence between these two types of motion of the photon is established. [ABSTRACT FROM AUTHOR]

The present paper records nine species of coralline algae from the Prang Formation of middle-late Eocene age from the Jaintia Hills, Meghalaya. The algae are associated with the larger foraminifera including Nummulites, Alveolina and Discocyclina throughout the succession. The temporal distribution of algal species indicates that seven species are known from the Eocene. Of the remaining two, one ranges from the Palaeocene to Eocene and the other is Palaeocene in age. The coralline algae and larger foraminifers are differentiated into two associations, the lower one indicating inner-ramp environment of high energy and the upper one showing deposition in relatively calm waters of deeper ramp environment. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To describe the extent of problem of diabetes in rural India based on review of available literature and examine the secular trends over a period of 15 years i.e. from 1994 to 2009. Methods: A systematic search was performed using electronic as well as manual methods. Studies providing details of sample size, age group of participants, criteria used for diagnosis, along with the prevalence of any of the three outcomes of interest i.e. diabetes mellitus, impaired fasting glucose (IFG) or impaired glucose tolerance (IGT), were included. Results: Analysis of secular trends reveals an increase in diabetes prevalence among rural population at a rate of 2.02 per 1000 population per year. The rate of increase was high in males (3.33 per 1000 per year) as compared to females (0.88 per 1000 per year). High prevalence of IFG and IGT has been observed in southern and northern parts of the country. Conclusion: The prevalence of diabetes is rising in rural India. There is a large pool of subjects with IFG and IGT at high risk of conversion to overt diabetes. Population-level and individual-level measures are needed to combat this increasing burden of diabetes. [Copyright &y& Elsevier]

The assumption of the existence of an energy field surrounding a rigid body is used to provide explanations of the probabilistic behavior of quantum particles in the physical phenomena such as interference, reflections, and refractions of light, and the spin states of the electron. The probability behavior arises from the boundary conditions under some circumstances, which lead to multiple solutions for the energy density inside the energy field of a quantum particle. Using these concepts the g factor for the spin magnetic moment of the electron in hydrogen atom is predicted to be 2.002 319 358. This compares well to its measured value of 2.002 319 304 362 2. [ABSTRACT FROM AUTHOR]

The Lamb shifts in energy between the 2S1/2 and 2P1/2 states of the electron inside the hydrogen atom and the deuterium atom are calculated using the equations of motion of a particle proposed by the author [P. K. Misra, Phys. Essays 2, 186 (1989); Phys. Essays 22, 478 (2009)]. It is shown that the calculated Lamb shifts between the 2S1/2 and 2P1/2 states, 1057.896 MHz for the hydrogen atom and 1059.343 MHz for the deuterium atom, compare favorably with their experimental values [M. Weitz et al., Phys. Rev. Lett. 72, 328 (1994)] of 1057.845 MHz and 1059.221 MHz, respectively. Furthermore, the Lamb shift for the 1S level for the hydrogen atom is predicted to be 8174.779 MHz compared to the experimental value of 8172.86 MHz. The difference between the predicted and the experimental values of the Lamb shifts in the hydrogen atom and the deuterium atom are small. The ability to predict the Lamb shifts lends support to the theory proposed by the author. [ABSTRACT FROM AUTHOR]

A personal narrative is presented which explores the author's experience of touring the streets of Kolkata

The paper investigates the concept of an energy field existing in the infinite space surrounding all rigid bodies. The properties of the energy field are analyzed and are shown to provide consistent results with the theories of relativity and quantum mechanics. Using Einstein's theory that energy and mass are equivalent, it is shown that a rigid body and its energy field form a continuum in space, and classical continuum mechanics theories can be applied to the motion of the rigid body and its energy field under an applied force. The total energy of motion, however, consists not only that of the motion of the body, but also an amount associated with the flux of momentum inside the field. These two types of energy need to be added as a complex variable vector to obtain the total energy. The resulting total energy formulation is consistent with the definition of energy in the theories of relativity. Using this concept, the equations of motion of a body under an applied force are derived in the form of two coupled equations, which, when combined to ensure that energy is summed as defined above, yield Schrödinger's wave equation for quantum mechanics consistent with the theories of relativity. In this sense we find the derived equations to be valid for quantum mechanics, classical mechanics, and theories of relativity, while presenting significant mathematical simplicity. [ABSTRACT FROM AUTHOR]

The present study records the discovery of megaplant fossils from the middle part of the Ediacaran Jodhpur Sandstone, exposed in the mines around Sursagar area (GPS location 26°20′03₺N; 72°59′72₺E), Jodhpur, Rajasthan. This is the first record of the giant size noncarbonaceous plant fossils from the Precambrian sequences. The fossils show well-developed thallus, branching pattern, development of possible oogonia and zoospores, and antheridea. Showing morphological similarity with the extant Vaucheriacean plant, the thallus is about 140 times bigger in size. Preserved on the top of the bed, these are also associated with welldeveloped microbial mats. The same horizon has also yielded poorly preserved circular structures with medusoidal affinity which can be compared with the Aspidella sp. [ABSTRACT FROM AUTHOR]

Diaspora and globalization are linked processes and are influenced by political, economic and technological changes. Seen in historical perspective the processes help in understanding identity formation. While multi-cultural identities have been applauded, serious class interest in each group is overlooked. Why? In the name of heritage diaspora communities are witnessing proliferation of places of worship. No doubt their roles in reinforcing the identities of the diasporic communities are discussed but not what hindrance they cause in their integration with the host societies. [ABSTRACT FROM AUTHOR]

Abstract: The absence of spontaneous and piezoelectric polarization in nonpolar-oriented III nitrides can improve emission efficiency in light-emitting devices due to the absence of electrostatic fields. It is therefore of interest to study the growth processes necessary to achieve smooth morphology for nonpolar-oriented films. In this paper, we compare and contrast gallium adsorption and desorption on C-, M-, and A-plane GaN epilayers by plasma-assisted molecular beam epitaxy (PAMBE) coupled with in-situ spectroscopic ellipsometry (SE). Adsorption/desorption of Ga under vacuum and under active nitrogen flux were investigated. Previous studies on C- and M-plane materials have suggested that optimum growth conditions with respect to surface morphology are those giving rise to a Ga bilayer and trilayer, respectively. Under vacuum, the stable Ga coverage was 0.48–0.50nm for the C-, M-, and A-planes. While under N plasma, C-plane GaN maintained similar Ga coverage, while a thicker Ga-stable coverage of 0.7nm was determined for M-plane. This is in contrast to A-plane GaN, which did not have a consistent Ga adlayer under plasma. We observed that Ga-rich growth of A-plane GaN leads to rough surface morphologies and N-rich conditions are necessary for smooth two-dimensional growth. [Copyright &y& Elsevier]

Abstract: Temperature dependence of the photoluminescence (PL) transitions in the range of 10–300K was studied for ZnO thin films grown on sapphire by pulsed laser deposition. The low temperature PL spectra were dominated by recombination of donor bound excitons (B X) and their phonon replicas. With increasing temperature, free exciton (F X) PL and the associated LO phonon replicas increased in intensity at the expense of their bound counterparts. The B X peak with line width of ∼6meV at 10K exhibited thermal activation energy of ∼17meV, consistent with the exciton-defect binding energy. The separation between the F X and B X peak positions was found to reduce with increasing temperature, which was attributed to the transformation of B X into the shallower donor bound exciton complexes at consecutive lower energy states with increasing temperature, which are possible in ZnO. The energy separation between F X peak and its corresponding 1-LO phonon replica showed stronger dependence on temperature than that of 2-LO phonon replica. However, their bound counterparts did not exhibit this behavior. The observed temperature dependence of the energy separation between the free exciton and it is LO phonon replicas are explained by considering the kinetic energy of free exciton. The observed PL transitions and their temperature dependence are consistent with observations made with bulk ZnO crystals implying high crystalline and optical quality of the grown films. [Copyright &y& Elsevier]

Abstract: We report a compact, conduction-cooled, highly efficient, continuous wave (CW) Nd:YAG slab laser in diode-side-pumped geometry. To achieve high efficiency, a novel laser head for Nd:YAG slab has been developed. For an absorbed pump power of 27.6W, maximum output power of 10.4W in multimode and 8.2W in near-diffraction-limited beam quality has been obtained. Slope and optical-to-optical conversion efficiencies are 45.3% and 37.7% in multimode with beam quality factors (M 2) in x and y directions equal to 32 and 8, respectively. TEM00 mode operation was achieved in a hybrid resonator with slope and optical-to-optical conversion efficiencies of 43.2% and 29.7%, respectively. Beam quality factors in x and y directions are ⩽1.5 and ⩽1.6 for the whole output power range. The laser radiation was linearly polarized and polarization contrast ratios are >1200:1 in the multimode and 1800:1 in the TEM00 mode operation. In passive Q-switching with Cr4+:YAG crystal of 68% initial transmission, 18ns pulsewidth has been achieved with an average power of 2W at a repetition rate of 16kHz. [Copyright &y& Elsevier]

Abstract: We have studied temperature dependent photoluminescence (PL) from ZnO Multiple Quantum Wells (MQWs) of different well layer thicknesses in the range ∼1–4 nm grown on (0001) sapphire by a novel in-house developed buffer assisted pulsed laser deposition. At 10 K the PL peak shifted toward blue with decreasing well layer thickness and at constant well layer thickness the PL peak shifted towards red with increasing temperature. To the best of our knowledge we have observed for the first time an efficient room temperature (RT) PL emanating from such MQWs. The red shift of the PL peak with increasing temperature has been found to be due to the band gap shrinkage in accordance with the Varshni’s empirical relation. The spectral linewidth was found to increase with increasing temperature due to the scattering of excitons with acoustic and optical phonons in different temperature regimes. Both at RT and at 10 K the PL peak shifted with respect to the well layer thickness in the range of ∼3.35–∼3.68 eV with decreasing thickness in agreement with the calculated values. [Copyright &y& Elsevier]

Atmospheric models constitute the best tools available for the setting of policy, and may, in some cases, be the only tools that are available. The best examples of their kind bring together all current knowledge of pollutant behavior in the atmosphere, making it possible to unravel the often complex interactions between pollutants and atmospheric dynamics. They also allow the possibility of evaluating hypothetical changes in emissions and other conditions to evaluate potential abatement strategies, or to assess the impact of proposed new emission sources. This paper provides an overview of mathematical atmospheric models and their application to the development of air quality policy. The paper discusses the types of atmospheric models currently in use, categorized by spatial scale, and the requirements for credible modeling. Issues associated with model validity and accuracy are described and case studies are reviewed to illustrate atmospheric model use in policy development and the need for careful analysis in interpreting model predictions. [ABSTRACT FROM AUTHOR]

Abstract: Pulsed Laser Deposition of high crystalline quality thin ZnO films on sapphire substrates necessitates a growth temperature of about 750 °C or higher while sharp interfaces in a multilayer structure suitable for optoelectronic devices are obtained at comparatively low growth temperatures. To meet these contradictory requirements a growth scheme has been evolved in which a ZnO buffer layer deposited at about 750 °C was found to facilitate high crystalline quality growth of a ZnO over layer even at 400 °C. The buffer layer grown at 750 °C was found to have its in plane lattice 30° rotated compared to that of the sapphire substrate and so was the case with the ZnO over layer grown at 400 °C on the buffer. The full width at half maximum of the high resolution X-ray diffraction rocking curves of (00.2) and (10.4) peaks of ZnO films grown at low temperature on the buffer were found to be ∼0.18° and ∼0.28°, respectively, which are comparable to 0.11° and 0.23° as observed in the case of films deposited directly at 750 °C and much better than the values of 0.46° and 0.48° seen in case of the films grown at 400 °C without any buffer layer. The buffer assisted low temperature ZnO growth also decreased the r.m.s. value of the surface roughness of the film to about 8 Å from about 40 Å of the one grown at high temperature without any buffer. [Copyright &y& Elsevier]

Surajit Chandra Sinha was a brilliant scholar, innovative methodologlst and a person gentle to the core. He made valuable contributions to anthropological theory as well as to its methodology. He trained and supervised the work of scores of young scientists. He encouraged dialogue and exchange of ideas. He made genuine efforts to explore the creative powers of the people, particularly of the folk populations. In the first part of this essay an attempt has been made to give an outline of the anthropological career of Sinha, the various research programmes he was involved in and the methodological innovations he made. In the second half of the essay the themes and issues discussed by Sinha have been highlighted. [ABSTRACT FROM AUTHOR]

High power Nd:YAG lasers with fiber optic beam delivery have introduced new capabilities for material processing applications. Here, we present the stable resonator design for high power Nd:YAG lasers to optimize beam quality for fiber optic transmission. Dependence of beam parameters on position and dioptric power of thermal lens has been investigated and optimized to achieve efficient fiber optic beam delivery. With the optimum resonator configuration, an efficient fiber optic beam delivery over the entire operating range of input power has been achieved. The results of stable resonator design with good beam quality and output power have been presented. [Copyright &y& Elsevier]

An omalies appear to exist in our understanding of atmospheric sulfur compounds, specifically as evidenced in the time trends of the different chemical forms of these compounds. Trends determined at a number of locations by several different groups seem to indicate that, responding to emission reductions across North America, the concentration of SO[sub2] in the atmosphere is declining more rapidly than that of aerosol SO[sub4, sup2-]. A number of possible reasons for this discrepancy are examined, but it is not possible to provide a definitive answer at this stage. The intent is to stimulate debate, because shortcomings in our understanding of the processes involved could have profound implications for the credibility of abatement strategies and policies for both acid deposition and fine particulate matter (PM). [ABSTRACT FROM AUTHOR]