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The National Iodine and Salt Intake Survey (NISI) 2014–2015 was undertaken to estimate household iodised salt coverage at national and sub-national levels in India.
Cross-sectional survey with multistage stratified random sampling.
India was divided into six geographic zones (South, West, Central, North, East and North-East) and each zone was further stratified into rural and urban areas to yield twelve distinct survey strata.
The target respondent from each household was selected as per predefined priority; wife of the household head, followed by women of reproductive age, followed by any adult available during the visit.
Households (n 5717) were surveyed and salt samples (n 5682) were analysed. Household coverage of iodised salt (iodine≥5 ppm) was 91·7 (95 % CI 91·0, 92·7) %. Adequately iodised salt (iodine≥15 ppm) was consumed in 77·5 (95 % CI 76·4, 78·6) % of households. Significant differences in coverage were seen across six geographic regions, with North and North-East zones on the verge of achieving the universal salt iodisation target of >90 % coverage. Coverage of households with adequately iodised salt (adjusted OR; 95 % CI) was significantly less in rural households (0·55; 0·47, 0·64), lower/backward castes (0·84; 0·72, 0·98), deprived households (0·72; 0·61, 0·85) as assessed by multidimensional poverty index, households with non-diverse diet (0·73; 0·62, 0·86) and households using non-packaged salt (0·48; 0·39, 0·59) and non-refined salt (0·17; 0·15, 0·20).
India is within striking reach of achieving universal salt iodisation. However, significant differentials by rural/urban, zonal and socio-economic indicators exist, warranting accelerated efforts and targeted interventions for high-risk groups.
The Proterozoic Sushina Hill Complex is the only agpaitic complex, reported from India and is characterized by a eudialyte-rinkite-bearing nepheline syenite. The complex is considered a ‘metamorphosed agpaitic complex'. This study describes the mineral assemblages formed during successive stages of evolution from magmatic to hydrothermal stages and low-temperature subsolidus re-equilibration assemblage. The primary-late magmatic assemblage is characterized by albite, orthoclase, unaltered nepheline, zoned diopside-hedenbergite, rinkite, late magmatic eudialyte and magnesio-arfvedsonite formed at ∼700°C with maximum aSiO2 of 0.60. In contrast, a deuteric assemblage (400-348°C) is represented by aegirine-jadeite-rich clinopyroxene, post-magmatic eudialyte, sodalite, analcime and the decomposition assemblages formed after eudialyte with decreasing aSiO2 (0.52-0.48). A further low-temperature subsolidus assemblage (≤250°C) represented by late-forming natrolite could be either related to regressive stages of metamorphism or a continuum of the subsolidus processes. Considering the P/T range of the greenschist - lower-amphibolite facies of metamorphism it is evident that the incorporation of a jadeite component within pyroxene is related to a subsolidus process between ∼400°C and 348°C in a silica deficient environment. We emphasize that the deuteric fluid itself acted as an agent of metamorphism and the decomposition assemblage formed after eudialyte is retained even after metamorphism due to the convergence of subsolidus and metamorphic domains. The formation of jadeite-rich aegirine is not considered to result from metamorphism. Overall it is near-impossible to discern any bona fide metamorphic textures or mineral assemblages in these syenites which appear to preserve a relict mineralogy regardless of their occurrence in country rocks which have experienced greenschist - amphibolite facies metamorphism. The Sushina complex is very similar in this respect to the Norra Kärr complex (Sweden).
This report covers the period July 1996 to June 1999. It has been prepared by the President of the Commission with contributions from the members of the Organizing Committee and Dr. E.M. Corsini. As discussed in Kyoto and decided by the Organizing Committee, the report is meant to be in the “short” version.
This report coveres the period 1 July 1993 to 30 June 1996. In contrast to reports from previous triennia, which were written by commission officers, committee members, and chairs of working groups, all members of the comission were invited, through a newsletter, to volunteer to write sections on topics that interested them. About a dozen people volunteered, not all of whom were able to complete the reports they had suggested.
The mechanism providing the 35-day period found in optical and X-ray light curves of the eclipsing low-mass X-ray binary Her X-l is considered to be the precession of a tilted and twisted accretion disc about the neutron star. We have obtained spectrophotometric observations of this system. The majority of line absorption and emission originates on or near the mass-losing primary, with distributions over the inner face of the star consistent with irradiation from the environs of the compact object. After suitable corrections for heating, the neutron star is found have a mass of 1.6±0.3M⊙, in contrast to the last radial velocity study which found a value less than 1.0 M⊙ . Rotational velocity measurements, while insufficiently precise to reject the older mass estimate, suggest that the rotational period of HZ Her differs from the synchronous rate by no more than 20%. Using a recently determined figure for the effective temperature of the unheated face, the distance to Her X-l is estimated at 6.7±0.4kpc, higher than prior estimates. The systemic velocity is found to be –69±6km s−1. In order to to determine the plausibility of the twisted disc model we reconstruct the expected shadow of the disc across the heated inner face of the donor star to compare with observation. Large scale emission structure is reproduced, but the model fails to synthesize finer observational details. HeII λ4686 Å emission is detected and found to be distributed closely about the neutron star, and is a likely tracer of the accretion flow.
We review the current understanding of accretion flows around compact objects with a special emphasis on advective disks. We discuss the influence of the centrifugal pressure supported high density region around compact objects (where shocks may also form) on the emitted spectra. We show that the stationary and non-stationary spectral properties (such as, low and high states, transition of states, quasi-periodic oscillations, quiescent and rising phases of X-ray novae, etc.) of both low mass and supermassive black hole candidates could be satisfactorily explained within the framework of the analytical solution of the advective disks without invoking any ad hoc components such as Compton clouds or magnetic corona.
Influenza A (H1N1) pdm09 became the predominant circulating strain in the United States during the 2013–2014 influenza season. Little is known about the epidemiology of severe influenza during this season.
A retrospective cohort study of severely ill patients with influenza infection in intensive care units in 33 US hospitals from September 1, 2013, through April 1, 2014, was conducted to determine risk factors for mortality present on intensive care unit admission and to describe patient characteristics, spectrum of disease, management, and outcomes.
A total of 444 adults and 63 children were admitted to an intensive care unit in a study hospital; 93 adults (20.9%) and 4 children (6.3%) died. By logistic regression analysis, the following factors were significantly associated with mortality among adult patients: older age (>65 years, odds ratio, 3.1 [95% CI, 1.4–6.9], P=.006 and 50–64 years, 2.5 [1.3–4.9], P=.007; reference age 18–49 years), male sex (1.9 [1.1–3.3], P=.031), history of malignant tumor with chemotherapy administered within the prior 6 months (12.1 [3.9–37.0], P<.001), and a higher Sequential Organ Failure Assessment score (for each increase by 1 in score, 1.3 [1.2–1.4], P<.001).
Risk factors for death among US patients with severe influenza during the 2013–2014 season, when influenza A (H1N1) pdm09 was the predominant circulating strain type, shifted in the first postpandemic season in which it predominated toward those of a more typical epidemic influenza season.
Infect. Control Hosp. Epidemiol. 2015;36(11):1251–1260
The importance of ZnxMg1-xO is increasing day by day because of its wider bandgap than ZnO. This ternary semiconductor finds its application in the fields of optoelectronics, spintronics, superlattices due to its unique blueshifted UV-luminescent property. n- to p-type conduction which is the motive of the project can be achieved with increasing Mg content in ZnMgO. The optical characteristics of the nitrogen doped ZnxMg1-xO (x=0.85) grown on 2 inch Si <100>wafer by RF sputtering are studied and analyzed thoroughly using low temperature (15K) photoluminescence measurements. Nitrogen implantation was carried out by Plasma immersion Ion Implantation technique on the sample. Rapid Thermal Process was employed to remove defects resulting from implantation. The samples were annealed at 700°C, 800°C, 900°C, and 1000o C for 10 seconds in an oxygen ambient. Photoluminescence (PL) measurements were performed at low temperature (15K) which exhibited acceptor-bound-exciton peak (A°X) and donor-bound-acceptor pair (DAP) at 3.336 eV and 3.236 eV respectively. At 3.364 eV, S peak was found for the sample annealed at 800°C after implantation. This peak was attributed to the existence of ZnO-like composition. Localized and de-localized exciton peaks were found around 3.42 and 3.45 eV respectively. This result is very important because though dominant acceptor peak was not found but proper optimization of the parameters can lead to p-type ZnMgO which is the main motive of this project.
Under controlled irradiation of low energy carbon ions, photoluminescence (PL) study of InAs quantum dots prepared with different capping structures (GaAs and InAlGaAs) was carried out. Samples were investigated by varying implantation energy from 15 keV to 50 keV with fluence ranging between 3 × 1011ions/cm2 and 8 × 1011 ions/cm2. For fixed fluence of 4 × 1011ions/cm2, low temperature PL showed enhancement in a certain range of energy, along with a blue shift in the PL peak wavelength. In contrast, with varying fluence at fixed implantation energy of 50 keV, PL enhancement was not significant, rather a drop in PL intensity was noted at higher fluence from 5 × 1011 to 8 × 1011 ions/cm2. Moreover, carbon ion implantation caused a blue shift in the PL emission peak for both energy and fluence variations. PL intensity suppression was possibly caused by the formation of non-radiative recombination centers (NRCs) near the capping layer, while the corresponding blue shift might be attributed to stress generation in the capping layer due to implantation. As-grown and implanted InAlGaAs capped samples did not exhibit much variation in full width at half maxima of PL spectra; however, significant variation was observed for the GaAs capped sample. These results validate that InAlGaAs-capped QDs are more immune to ion implantation.
Many boundary value problems occur in a natural way while studying fluid flow problems in a channel. The solutions of two such boundary value problems are obtained and analysed in the context of flow problems involving three layers of fluids of different constant densities in a channel, associated with an impermeable bottom that has a small undulation. The top surface of the channel is either bounded by a rigid lid or free to the atmosphere. The fluid in each layer is assumed to be inviscid and incompressible, and the flow is irrotational and two-dimensional. Only waves that are stationary with respect to the bottom profile are considered in this paper. The effect of surface tension is neglected. In the process of obtaining solutions for both the problems, regular perturbation analysis along with a Fourier transform technique is employed to derive the first-order corrections of some important physical quantities. Two types of bottom topography, such as concave and convex, are considered to derive the profiles of the interfaces. We observe that the profiles are oscillatory in nature, representing waves of variable amplitude with distinct wave numbers propagating downstream and with no wave upstream. The observations are presented in tabular and graphical forms.
We report a theoretical study of dissociative recombination (DR) of BeH+ by
low energy electron impact, using previously computed molecular data as input for a
Multichannel Quantum Defect Theory (MQDT) approach. Three electronic symmetries of BeH,
2Π, 2Σ+, and 2Δ have been included in the
calculations. We present cross sections and thermal rate coefficients ready to be used in
the modelling of the BeH+ abundance in the interstellar medium and stellar
NASA's NuSTAR observatory is the first focusing hard X-ray telescope. Launched in June 2012, NuSTAR is sensitive in the 3–79 keV range with unprecedented ~17″ FWHM angular resolution above 12 keV, a result of its multilayer-coated optics and 10-m focal length. With its large effective area (900 cm2 at 10 keV), NuSTAR has point-source sensitivity ~100 times better than previous hard X-ray telescopes. Here we describe NuSTAR and its planned work on rotation-powered pulsars and magnetars during its nominal 2-yr baseline mission that has just commenced.
The electronic structure of CeAg2Ge2 single crystal has been investigated by using resonant valence band photoemission and angle-resolved photoemission spectroscopy at different photon energies. Resonant photoemission has been observed near the 4d threshold of Ce at 121 eV. The constant initial state spectra show two photoemission features having 4f character near the Fermi level that exhibits Fano-like sharp resonance profile. Experimental energy bands have been mapped from the normal-emission photoelectron spectra of CeAg2Ge2 (001) surface along the Γ–Z direction. Four photoemission features are observed to show the dispersion related to the Ce 4f states and the hybridized Ag 4d with Ge 4p states. The experimental spectra have been interpreted with the help of calculations based on full potential linear augmented plane wave method using density functional theory.
The formation of shallow (0.05–0.2 μm) p+ layers in GaAs by pulse diffusion of Zn from a doped oxide source, thermal diffusion of Cd by vapor transport, or by low energy implantation of Cd, Mg, Be, Zn or Hg ions was investigated by electrochemical capacitance-voltage profiling, Secondary Ion Mass Spectrometry, Rutherford backscattering and Hall measurements. Hole densities in excess of 1019 cm−3 are obtainable by either Zn diffusion or acceptor implantation, though the high temperature cycle must be kept to ≤3 sec at (≤1000°C to prevent excessive redistribution of the acceptor dopants. Pulse diffusion at temperature °C leads to shallow regions with atomic concentrations above 1019 cm−3, but electrically active concentrations orders of magnitude less. These results are explained in terms of the unavailability of a sufficient density of vacancies at low temperatures.
AℓN deposited by D.C. triode sputtering and spin-on, phosphorus-doped glass (PSG) layers on GaAs and InP were investigated as encapsulants. These films have similar expansion coefficients to both GaAs and InP, minimizing the amount of strain induced in the near-surface region of the underlying wafer. We have quantified this effect by direct measurements of the stress in the films and by using secondary ion mass spectrometry profiling to measure the redistribution of Cr and Fe in encapsulated GaAs and InP respectively during high temperature processing. The dopant redistribution is considerably less for the AℓN and PSG films compared to the more conventional SiO2 and Si3N4 layers. The interaction of the films with the substrate at elevated temperatures is minimal as determined by Auger profiling and the electrical properties of the surface after removal of the encapsulants. The composition of the films remains essentially constant after annealing, as measured by Rutherford backscattering, and the thickness uniformity over large wafer diameters (2″) can be excellent with close control of the deposition parameters. The activation characteristics of low dose, Si-implanted layers in GaAs using either PSG or AℓN are comparable to those obtained using capless annealing or SiO2 or Si3N4 encapsulation.
The damage introduced into GaAs/AlGaAs HEMT structures during pattern transfer (O2 plasma etching of the PMGI layer in a trilevel resist mask) or gate mesa etching (CCl2F2/O2 or CH4/H2/Ar etching of GaAs selectively to AlGaAs) has been studied. For etching of the PMGI, the threshold O+ ion energy for damage introduction into the AlGaAs donor layer is ∼200 eV. This energy is a function of the PMGI over-etch time. The use of ECR-RF O2 discharges enhances the PMGI etch rate without creating additional damage to the device. Gate mesa etching produces measurable damage in the underlying AlGaAs at DC negative biases of 125–150V. Substantial hydrogen passivation of the Si dopants in the AlGaAs occurs with the CH4 /H2 /Ar mixture. Recovery of the initial carrier concentration in the damaged HEMT occurs at ∼400°C, provided the maximum ion energies were dept to ≤400 eV. Complete removal of residual AIF3 on the CCl2F2/O2 exposed AlGaAs was obtained after H2O and NH4 OH:H2O rinsing while chlorides were removed by H2O alone.
There are two basic gas chemistries used for dry etching of III-V semiconductors. The most common discharges contain chlorine, but these generally give rise to somewhat rough surface morphologies for In-containing compounds. More recently methane/hydrogen mixtures have been demonstrated to give low rate, smooth etching of In-based materials. In this work we describe the use of gas mixtures containing both CH and CI species. The hydrochlorofluorocarbons CHCl2F and CHCIF2 with O2 or H2 addition were used to reactively ion etch GaAs, InP, AlGaAs, GaSb, InGaAs and AlInAs as a function of etch time, plasma power density, pressure and gas composition. At moderate power densities (0.56 W · cm−2) the etch rates are in the range 125 Å · min−1 (AlInAs) to 1000 A · min−1 (GaAs). All of the materials exhibit smooth surface morphologies over a wide range of RIE parameters and there is no significant lattice disorder introduced for low power RIE as evidenced by PL and diode I-V measurements. Thin (≤40 Å) surface residue layers of CI (3–9 at. %) and F(≤3 at. %) for all materials except AlInAs are present after dry etching, but these can be removed by simple solvent cleaning.
Scaling the performance of metamaterials to obtain negative refractive index at optical frequencies has been of great interest. One of the great barriers to the scaling is that real currents cannot be driven at very high frequencies and one is more dependent on displacement currents to generate negative magnetic permeability. Moreover to keep the dimensions of the metamaterials physically accessible, the structural lengthscales of the metamaterials begin approach the wavelength of the radiation in free space and homogenisation is often questionable. Here we will show that metamaterials such as Split ring resonators in these high frequency limits exhibit complex behaviour. Magnetic activity and Negative refractive index behaviour can, indeed, be obtained at optical frequencies but will need to be interpreted very carefully. The plasmonic nature of the metallic system and excitation needs to be considered in detail.
HI/H2/Ar discharges are shown to be universal etchants for rn-V semiconductors, giving rise to highly anisotropic features with smooth surface morphologies. At loy dc self bia:s (-100V) and low pressure (1 mTorr), etch rates for all III-V materials of >2000Å min−1 are possible for high HI percentages in the discharges, whereas rates greater than 1 Åm min−1 are obtained at higher pressures and dc biases. These etch rates are approximately an order of magnitude faster than for CH4/H2/Ar mixtures under the same conditions and there is no polymer deposition on the mask or within the reactor chamber with HI/H2/Ar. Auger Electron Spectroscopy reveals residue-free, stoichiometric surfaces after dry etching in this mixture. As i result, photoluminescence intensities from dry etched samples remain high with little apparent damage introduction. Changes in the near-surface carrier concentration due to hydrogen passivation effects are also negligible with HI-based mixtures in comparison to CH4-based dry etching.
Near-surface damage created by Ar+ ion milling in InP and GaAs was characterized by capacitance-voltage, current-voltage, photoluminescence, ion channeling and transmission electron microscopy. We find no evidence of amorphous layer formation in either material even for Ar+ ion energies of 800eV. Low ion energies (200eV) create thin (≤100 Å) damaged regions which can be removed by annealing at 500°C. Higher ion energies (≤500 eV) create more thermally stable damaged layers which actually show higher backscattering yields after 500°C annealing. Heating to 800°C is required to restore the near-surface crystallinity, although a layer of extended defects forms in GaAs after such a treatment. No dislocations are observed in InP after this type of annealing. The electrical characteristics of both InP and GaAs after ion milling at ≥500 eV cannot be restored by annealing, and it is necessary to remove the damaged surface by wet chemical etching. For the same Ar+ ion energies the damaged layers are deeper for InP than for GaAs-after 500 eV ion milling at 45° incidence angle, removal of ∼485 Å and ∼650 Å from GaAs and InP respectively restores the initial current-voltage charaeteristics of simple Schottky diodes.