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The time-lag method is the most useful technique to determine gas permeability, diffusivity, and solubility. However, it is difficult to evaluate the transport properties of the membrane accurately because gas permeability depends on the technique used to assess gas flow. The significance of the present study is to design an economic isochoric apparatus to accurately measure micro-range gas flow rates ranging from 10−6 to 10 cm3(STP) s−1. A strategic procedure is demonstrated to eliminate possible artifacts while conducting the gas permeation experiments, including utilizing downstream pressure rise profiles to identify nanoscale defects as well as transient and steady-state permeation. An indigenous apparatus was developed to estimate the polymeric intrinsic properties of the dense and thin-film composite membranes. The device has been successfully used to measure the gas permeation flow rate ranging from 1 × 10−5 to 1 × 10−1cm3 (STP) s−1, which indicates the broad applicability and reproducibility of the data suggesting the reliability of the designed apparatus. Permeation flow rates of binary mixtures of CO2/CH4 through the defect-free membranes were compared with the numerical estimations to validate the measured transport properties. [ABSTRACT FROM AUTHOR]

The prime intention of this article is to investigate the effect of variable bottom topography and a bottom-sitting porous barrier on the hydroelastic response of an elastic plate floating on a two-layer fluid using small amplitude wave theory. Galerkin's single-mode approximation in each layer for variable bottom topography and the method of eigenfunction expansion for the fluid region of uniform bottom topography are used as mathematical tools to detail the phenomena. In the variable bottom topography, a system of differential equations is solved. By applying matching conditions, jump conditions, and the appropriate boundary conditions, the solution is expressed as an algebraic linear system from which all the unknown constants are evaluated. The effects of different parameters related to the fluid, bottom topography, and porous barrier on the bending moment, shear force, and deflection of an elastic plate are explored. The variations in the bending moments, shear forces, and plate deflection with respect to fluid density are found to be in opposite trends, caused by surface and interfacial waves, respectively. Further, as the density ratio becomes closer to one, the bending moments, shear forces, and plate deflection tend to diminish for interfacial waves. The bottom effect on bending moments, shear forces, and plate deflection is minimal due to surface waves but significant due to interface waves with maximum amplitude in a concave up bottom. The plate deformation can be further reduced using a suitable barrier, as investigated in this article. The findings hold good potential for furthering our understanding of installing an elastic plate in a stratified fluid with fluctuating water depth. [ABSTRACT FROM AUTHOR]

Nanocomposites have been demonstrated to have much lower density, higher viscoelasticity and can have tunable physical and chemical properties compared to metal alloys. The main advantage of nanofillers reinforcement in the polymer matrix for underwater application has been highlighted in terms of lower water intake as well as less debonding in ionic medium. The different types of fibre-reinforced polymer nanocomposites have been fabricated in order to understand the role of nanofillers at polymer matrix inside the saline water. The bonding of protective coating with the resin surface was found to be affected in salt water whereas the nanofillers were found to diffuse into the empty space of polymer matrix and provide comprehensive chemical resistance in ionic environment. It has been established that the gel coating of the composite was not stable under the dynamic water flow and pressure. On the other hand, nanofillers has been found to comprehensively plugged the voids in polymer and fibers interfaces which showed much higher stability in marine environment by delaying the ageing of structures for offshore applications. [ABSTRACT FROM AUTHOR]

A cost-effective process for preparation of aluminum nitride was developed by using single-source precursor tris (N,N dimethylethylenediamine)AlCl3, which was prepared from anhydrous aluminum chloride and N,N dimethylethylenediamine (DMEDA) in 1:3 molar ratio at room temperature under N2. The pyrolysis of the precursor was carried out at various temperatures, pressures, and flow of gases (N2 and Ar) to optimize parameters. The resultant pyrolyzed residues were investigated using various instrumental techniques. X-ray diffraction (XRD) showed that AlN crystallizes in mixed-phase (hexagonal/cubic) and the grain size was estimated to be in the range of 4–10 nm. The band gap of AlN was investigated by UV-Vis spectroscopy and found to be ∼5.7 eV (6.1 eV bulk); TEM showed agglomerated crystallites of AlN. [ABSTRACT FROM AUTHOR]

2-Aminothiazoles have been synthesized by a one-pot, two-step sequential procedure in solution state which does not involve the isolation of intermediates. It involves α-halogenation of corresponding precursor ketones followed by condensation with substituted thiourea derivatives. All the products were analyzed by IR, NMR, mass spectral techniques and four of them were evaluated crystallographically. One of them crystallizes in the triclinic crystal system with space group P 1 ¯ , while, all the other compounds crystallize in the monoclinic crystal system in two different space groups viz. P21/c and P21/n. The modified 2-aminothiazole core did not show any change in the intermolecular interaction. The N-H...N interaction predominates over other interactions forming centrosymmetric head to head dimer with the neighboring atoms. This feature is observed in all the molecules except N-(4-(4-bromophenyl)-3-(2,5-dimethylphenyl)thiazol-2(3H)-ylidene)-2,5-dimethylaniline. [ABSTRACT FROM AUTHOR]

The objective of this study was to evaluate the protective effect of apigenin against radiation-induced gastrointestinal (GI) damages in whole-body irradiated (WBI) Swiss albino mice. Swiss albino mice were pre-treated with apigenin (15 mg/kg body wt.) intraperitoneally for six consecutive days, and on the seventh day, the mice were exposed to 7 Gy WBI. Histological findings revealed a deterioration of the crypt-villus architecture in the 7 Gy irradiated mice intestine. Conversely, apigenin pre-treatment ameliorated radiation-induced intestinal damages and restored intestinal crypt-villus architecture. Besides, apigenin modulates 7 Gy radiation-induced apoptotic markers (p53, p21, Bax, caspase-3, −9) expression in the GI tissue of WBI mice. Furthermore, apigenin prevented radiation-induced activation of NF-kB expression in the GI tissue. Therefore, the present results indicate apigenin's radioprotective effect through modulating NF-kB mediated apoptotic signalling in the WBI intestinal tissue. [ABSTRACT FROM AUTHOR]

Samarium modified SrBi4-xSmxTi4O15 (x = 0, 0.13, 0.43 and 0.78) ferroelectric ceramics of Aurivillius family were prepared by conventional solid state reaction method. X-ray diffraction studies confirm the formation of a single-phase. Microstructural images show randomly oriented palate-like structure. Broad dielectric peaks were found to obey the modified Curie-Weiss law. The overall inherent ferroelectric nature was explained on the basis of the Avrami model. Furthermore, with increasing the Sm3+ content, the grain morphology and diffusive parameters have shown a comprehending impact on the ferroelectric (hysteresis) behavior. [ABSTRACT FROM AUTHOR]

The addition of thermally conducting nanomaterials to any base fluid may enhance the thermal conductivity of the fluid, but the higher cost of production of these nanomaterials limit its use. Therefore, synthesis/production of low cost thermally conducting nanomaterial is the need of the date. The objective of this work is the synthesis of thermally conducting low-cost nanomaterial for development of thermally conducting nanofluids. One dimensional Carbon Nanorods (CNRs) have been isolated and prepared from candle soot via the chemical route followed by the development of CNRs based flower-like morphology "Carbon Nanoflower." In this contribution, we present soot, a very cheap source for the preparation of carbon nanorods and hence is better than other methods of production of CNRs in terms of cost and ease of production. The CNRs based thermally conducting nanofluids was developed for heat transfer application. The as isolated carbon nanorods with moderate aspect ratio have very good crystallinity and thermal stability; with the size varying from 10 × 200 nm to 500 nm × 1.5 µ, the majority of nanorods with size ~(10 × 100 nm), as analyzed from the TEM image analysis. The size of CNRs isolated was further confirmed by DLS analysis, which is well correlated with the size obtained by the TEM analysis. The CNRs was further characterized by; X-ray diffraction (XRD), selected area electron diffraction (SAED), FT-IR, UV–vis absorption spectroscopy, Raman spectroscopy, and TGA, and results were well corroborated with CNR. The low-cost CNRs were prepared and CNR based nanofluid was developed. The maximum enhancement in the thermal conductivity of nanofluid with respect to base fluid (water and ethylene glycol) was observed to be 12%; which is a promising result for heat transfer application. [ABSTRACT FROM AUTHOR]

Natural gas hydrates are considered as a strategic unconventional clean hydrocarbon resource in the energy sector. This paper analyzes the spatiotemporal effectiveness of the depressurization technique for producing methane gas from an unconfined Class 4 clayey setting in the Krishna Godavari (KG) basin, east coast of India. The production potential of a well by depressurization based on the borehole-based pumping technique is modeled using the newly developed spatiotemporal numerical tool, IndHyd 1.0, built using MATLAB for a constant borehole ΔP. The model is aided by TOUGH+HYDRATE reservoir production simulation software. From the IndHyd 1.0 simulation results, it is identified that a vertical well in the location NGHP-01-10D could have a lateral well reach, longevity, and a cumulative methane gas production potential of 145 m, 1.2 years, and ∼0.6 billion m3, respectively. For the formation with a postdissociation permeability of 200 mD, a possible scenario in the fractured settings, the well reach, longevity, and gas production potential could be 340 m, 3.6 years, and ∼9 billion m3, respectively. [ABSTRACT FROM AUTHOR]

Carbon nanoparticles (CNPs) are synthesized from candle soot and subjected to fractional isolation and characterization. Highly thermally stable (onset of degradation 697°C) and crystalline CNPs (size 20-25 nm) of superior purity were isolated by multistage separation and isolation process. In isolation process, various other fractions with sizes less and more than the size 20-25 nm were isolated and characterized. Nanolubricating fluid was prepared with purest fraction isolated and SAE 30 engine oil and its wear preventive property was evaluated. About 29% reduction in wear scar diameter with smoother wear scar morphology was observed, which exhibits good wear preventive property of nanolubricating fluid. [ABSTRACT FROM AUTHOR]

The recent research in biocompatible materials has been useful in replacing and supporting the fractured natural human bones/joints. Under some condition, negative reaction like release of ions from the bare metal toward the human body fluid leads to corrosion. In this proposed research paper, the biocompatibility of the laser surface-modified austenitic stainless steel (SS316L) and nickel-based superalloy (Inconel 718) was studied. The investigation on laser-modified surfaces is evaluated through electrochemical polarization analysis using simulated body fluid (SBF). The samples subjected to electrochemical polarization analysis were characterized by optical image analysis, SEM, EDS, and XRD analysis. It was inferred that laser surface-modified materials provided enhanced corrosion resistance and bare nickel alloy is more susceptible to corrosion by SBF. [ABSTRACT FROM PUBLISHER]

Bismuth layered structure ferroelectric materials of Aurivillius family have been attracted on account of their inherent-ferroelectric properties. Rare earth modified two layered compound, namely, Bi3TiNbO9has been found to be a relaxor ferroelectric material, and therefore much attention is being concentrated to enhance the dielectric properties with different modifications. In view of this, Sm-modified novel ceramic(Bi2SmTiNbO9) was prepared by the conventional solid-state reaction method. Impedance spectroscopic measurements were made as a function of frequency at different temperatures. Electrical studies were also made, and the results were corroborated to the Raman spectroscopic data. [ABSTRACT FROM AUTHOR]

Bismuth titanate (BT-‘Bi4Ti3O12’) is one of the extensively studied materials of the Bismuth layered structure ferroelectric (BLSF) family for its large spontaneous polarization along c-axis. In the present investigation, we have synthesised SmxBi4-xTi3O12(x = 0.37, 0.57, 0.72) ceramics using the conventional solid-state reaction method. The dielectric anomaly was observed near 450°C. Well-broad hysteresis loops were observed above room temperature up to 100°C. The coercive field (Ec) and consistent remanent polarization (Pr) values with temperature, compared to BT, indicates that the title compound has good promising ferroelectric-nature. This phenomenon is attributed to the easy recovery of defects (such as oxygen vacancies) accumulated at grain-interfaces, above room temperature, resulting in to well-hysteresis behaviour. The results were further confirmed with remanent polarization (2 Pr vs. temperature) plots. [ABSTRACT FROM AUTHOR]

Single-phase bismuth layered structure ferroelectromagnet (BLSFEM) LaGdxB5-xFe2Ti3O18of composition (x = 0.1, 0.2, 0.4, 0.6 and 0.8), novel ceramics were prepared by solid state route. Electrical and impedance measurements were made on the ceramics. Complex Impedance spectroscopic plots showed the signature of magnetic ion (Gd) and the results were corroborated to the Debye and Gaussian fitting curves. The variation of dielectric and modulus with temperature plots were used to explain dielectric phenomenon. An attempt is made to understand the effect of magnetic (Gd) ion on A site of (Bi2O2)2+(LaGdxBi3-xTi3Fe2O16)2−, layered perovskite (title) compound. [ABSTRACT FROM AUTHOR]

The large-scale land conversions to urban impervious surfaces, loss of lakes and occupation of floodplains, have resulted in many problems like urban heat island, depletion of the ground water and more importantly flash floods. The impervious surfaces of urbanization led to accelerated run-off and reduced recharge. Currently, around 280 locations are vulnerable to flash floods in the Bangalore city of India. The dumping of solid waste, laying of cables in the channels, under-potential culverts and allotment of the floodplain for housing purposes has developed vulnerability to frequent flooding. Increased urbanization with intensified vertical growth of the city has led to the liquid waste disposal along the storm water drains making the run-off models unpredictable. The breach of lake embankments and overflowing lakes at the initial monsoon rains is the popular phenomenon as the lakes are silted and saturated with sewage. Efforts of revival of some lakes and desilting storm water drains have not improved the overall circumstance. Floods are reported even in short rainfall of 30 mm per hour. Adoption of the dual piping system to carry the wastewater and the rainwater would make restoration more meaningful. Multiple criteria evaluation of spatial layers in GIS environs provides a better assessment of vulnerable flash flood regions. For strategic plans, results from this investigation intuit in building a self-sufficient eco-friendly sustainable smart city that conserves the rainwater and avoid flooding in low-lying regions. The outcomes of the study guide in developing proper structures to the present urban situation, thereby implementing sustainable alternative development. [ABSTRACT FROM AUTHOR]

The bismuth layer structured ferroelectric (BLSF) ceramics consisting of four-layers (BaLa0.75Bi3.25Ti4O15) and five-layers (Ba2La0.75Bi3.25Ti5O18) were prepared by the conventional solid-state reaction method. Summerfield ac-conductivity scaling analysis was used to evaluate the electrical behavior and the ac-conductivity isotherm curves. The relaxation results were corroborated with the Raman Peak positions and full width at half maximum was obtained by using Lorentzian peak fit method. Finally, the results were compared with the two-layered relaxor-compound (Bi2.45La0.55TiNbO9) and technologically standard three-layered compounds (La0.75Bi3.25Ti3O12; BLT). The dielectric relaxation of Bi2.45La0.55TiNbO9was verified using modified Curie-Weiss law and Vögel-Fulcher relationship. An attempt is made to realize the typical collective nature of the ionic conductivity of the samples. [ABSTRACT FROM AUTHOR]

Oxygen-deficient and charge- imbalanced polycrystalline materials of three-layered Auruvillius compound, namely Sr2Bi2Nb3O12(SBN), was synthesized by Sol-Gel method. X-ray diffraction analysis was made on SBN and lattice parameters were calculated. Electrical impedance and Pyroelectric measurements were performed on SBN. The broad peak observed in the dielectric permitivity data indicates that the transition is diffused phase transition (DPT) and the modified Curie-Weiss law was used to describe the DPT of SBN. The sharp intensity peak observed at 176 and 219 cm−1in Raman spectra is an indicative of Sr-O-Sr and Sr-O-Bi bonds and its competitive interactions. The peaks of FTIR spectra appeared at 610 cm−1confirmed the same. The nature of difffused type was attributed to compositional heterogenity and the results were corroborated with the log-log spectroscopic plots of impedance,modulus and permitivity for better understanding of the disorder ferroelectric behavior of the sample. The broad semicircle behavior observed in the complex impedance aswell as modulus plot, associated with grain and grain boundary, confirm the same. [ABSTRACT FROM AUTHOR]

Lanthanum and vanadium modified polycrystalline material of La0.75Bi3.25Ti2.9625V0.03O12(BLVT) of Aurivillius family, was prepared by conventional solid-state reaction method. X-ray diffraction showed single phase with orthorhombic structure. Electron microcopy was done on as-sintered and oxygen-annealed samples. Impedance studies of BLVT showed multiple impedance relaxations. Based on the impedance factor (related to full width at half maximum) and master plots, the relaxations are found to be collectively competitive. A broad dielectric peak and Curie-Weiss diffused parameter indicates diffused phase transition. Complex impedance analysis along with the log-log spectroscopic plots was studied on BLVT at 500°C. But complex impedance plot of BLVT showed single broad semicircle, unlike La0.75Bi3.25Ti3O12(BLT), which showed three semicircles on separately coated silver- and platinum- ceramic disks. However, complex modulus plot (complimentary to impedance) of BLVT showed three semicircles, which clearly indicates the tendency of formation of space charges, which might result in the accumulation of defects at electrode-ferroelectric interfaces, and considered to be a characteristic feature of the sample. In view of this, some of the BLVT samples were annealed in oxygen- and vacuum. Detailed ac-conductivity analysis suggests that double oxygen vacancies play vital role in conduction phenomenon. [ABSTRACT FROM AUTHOR]

Novel polycrystalline materials of bismuth substituted barium titanate, namely, BaBixTi1-xO3-δ, (x = 0.025, 0.075, 0.125 and 0.175) was prepared by sol-gel chemical route and characterized by X-ray diffraction and scanning electron microscopy. Bismuth ion was added in place of titanium of B-site of ABO3 perovskite structure and both the site-balance as well as charge-balance was considered. The substitution of bismuth for Ti-site is clearly seen in both the XRD as well as IR spectroscopic data. Dielectric and impedance analysis were also made on the present novel ceramics. The above mentioned substitution involves ionic compensation, through creation of cation vacancies and is explained by proposing the defect dynamics. The results were corroborated with dielectric and complex impedance analysis for further understanding of ionic motion in this kind of disordered diffused materials. [ABSTRACT FROM AUTHOR]

Purpose. The objective of this study was to investigate EMG signals of cervical muscles in five directional efforts from chronic neck pain patients and compare them with those of the healthy controls to discern differences between patients and controls with respect to strength and EMG characteristics. Method. Seventeen male and 17 female idiopathic and non-specific chronic neck pain patients without any diagnosed pathologies or prior surgery in the age group 18-65 years were recruited into the study. The controls consisted of 30 male and 33 female subjects with no history of neck pain in the past 12 months. Both patients and controls performed the experimental activities of flexion, left anterolateral flexion, left lateral flexion, left posterolateral extension and extension. The patients exerted to their 20% maximum voluntary contraction (MVC), pain threshold and pain tolerance levels in three separate contractions. Similarly, the control subjects exerted to their 20% MVC, 60% MVC and MVC in random order. The descriptive statistics for strength, normalised peak EMG, median frequency (MF), 10% frequency bands and their power were calculated. Eight levels of wavelet decomposition and their coefficients were calculated and subjected to principal component analysis. These variables were subjected to analysis of variance and regression analysis to distinguish between patients and controls. The full wave rectified linear envelope detected EMG of patients and controls were plotted against time to reveal pattern differences. Results. There was a lack of significant difference in the MF of the two samples indicating that the muscle conduction velocity was not disturbed by the pain. Significant differences were also found in 10 percentile frequency bands between patients and controls ( p < 0.05). The wavelet decomposition with principal component analysis revealed that patients and controls could be identified as such 100% of the time at 20% MVC; and, patients and controls could be identified correctly 100% and 90% of the time respectively at pain threshold/60% MVC. Conclusion. Thus, a combination of EMG spectral frequency banding and wavelet decomposition with regression can be used to distinguish chronic pain patients from controls. [ABSTRACT FROM AUTHOR]

Tri-Valent (Sm3+/ Dy3+) and pentavalent (Nb5+) modified polycrystalline material of Aurivillius family, namely R0.75Bi3.25Ti2.9625.Nb0.03O12 (R = Sm, Dy), were prepared by conventional solid-state reaction method. Impedance and pyroelectric measurements were carried out to understand the electrical properties of the samples. Master plots were drawn to understand the defect role, especially vacancies, and the results were corroborated with the dc-conductivity data. Finally, both the complex impedance spectroscopic as well as pyroelectric results were compared with the impedance data of technological important materials, namely La0.75Bi3.25Ti3O12 (BLT) and lead zirconium titanate (PZT) for the further understanding of defects and its effects at the grain interfaces. [ABSTRACT FROM AUTHOR]

The effect of end cap and PZT materials on the acoustic performance of Cymbal transducer was attempted. Generally there are three frequency bands of interest for identification of the objects in shallow and deep water environments. These are from 1 kHz to 10 kHz; 10 kHz to 100 kHz and 100 kHz to 1 MHz. Currently there is an interest in the lower frequency band and that can be addressed by using cymbal transducers. Cymbal is class V flextensional transducer, it consists of cylindrical ceramic disk sandwiched between two cymbal shaped metal caps with hollow cavities. Cymbals are used as both sound projectors and receivers. Finite Element Analysis (FEA) ATILA code was used to analyze the performance of sound projector and receiver. Three typical ceramic disks and materials used as driving elements and end caps respectively were included in this study. [ABSTRACT FROM AUTHOR]

Nano particulate Barium Bismuth Titanate (BaBixTi1-xO3-δ) materials with (x = 0.25, 0.075. 0.125 and 0.175) were prepared through sol-gel chemical route (Pichini method) and the XRD patterns were indexed on the basis of tetragonal-BaTiO3 phase. The electrical impedance measurements were carried out on the samples by using Auto Lab PGSTAT30 impedance analyzer in the frequency region 100 Hz-1 MHz from RT to 500°C. Impedance spectroscopic and complex explicit plots show the presence of both bulk and grain boundary effects, and impedance spectroscopy is shown to be an efficient method capable of detecting the conductivity species and estimating the electrical conductivity as well as activation energy value. Finally, the results are interpreted in terms of the defect dynamics and conduction mechanisms taking place in the samples. [ABSTRACT FROM AUTHOR]

Tri (Dy3 +) and pentavalent (Nb+5) modified new polycrystalline material of Aurivillius family (Dy0.75Bi3.25Ti2.9625Nb0.03O12) was prepared by solid-state reaction method and the lattice parameters were calculated by using X-ray diffractogram. Impedance measurements were carried out from room temperature to 500°C in the frequency range of 100 Hz to 1 M Hz. Impedance spectroscopic plots show non-Debye type and detailed ac-conductivity analysis was also employed to understand the heterogeneity of the present electro-ceramics. The results were corroborated with the proposed defect formula and in addition, thermal stimulated current measurements show that the present sample has an excellent pyroelectric response. [ABSTRACT FROM AUTHOR]

The concentration of radon daughters in outdoor air was measured continuously from January 2006 to December 2006 near the Department of Physics, Bangalore University campus, Bangalore. The concentration was measured by collecting air samples at a height of 1 m above the ground level on a glass micro fibre filter paper with a known air flow rate. The results show that the radon progeny concentration exhibits distinct seasonal and diurnal variations that are predominantly caused by changes in the temperature gradient at the soil-atmosphere interface. The concentration was found to be high from 20.00 to 8.00 hrs, when the turbulence mixing was minimum and low during the rest of the time. In terms of the monthly concentration, January was found to be the highest with September/August being the lowest. The diurnal variations in the concentrations of radon progeny were found to exhibit positive correlation with the relative humidity and anti-correlation with the atmospheric temperature. From the measured concentration, an attempt was made to establish the annual effective dose to the general public of the region and was found to be 0.085 mSv/a. In addition, an attempt was also made for the first time to study the variation of inhalation dose with respect to the physical activity levels. Results show that in the light of both the effect of chemical pollutants and radiation dose due to inhalation of radon daughters, evening jogging is advisable. [ABSTRACT FROM AUTHOR]

Impedance spectroscopic measurements were carried out on lead based ferroelectric ceramics, namely PZT, PLZT and PMN-PT, in the frequency range of 0.1 Hz-1 MHz. Spectroscopic plots showed broad peaks, and are found to shift towards higher frequency side. Apart from this, both Z'' and M'' spectroscopic peaks are found to coincide almost in the same frequency region. This indicates approximated-Debye behavior. Frequency dependent conductivity plots show two slopes at lower and higher frequency regions. Low frequency relaxations are found to be non-exponential. Bulk relaxation vs. temperature plots are found to obey Arhenius linear fit. The relaxation at lower frequency and higher are attributed to Kohlrausch-Williams-Watt (KWW) type and migration of slow oxygen and lead vacancies. The results are corroborated to the conduction barrier hopping mechanism and new Eyraud's conductivity model. [ABSTRACT FROM AUTHOR]

Potable waters from various locations of the Bangalore environment were investigated for their 222Rn concentrations by the emanometry method. About 94 groundwater (borewell) samples were analysed for 222Rn concentrations and found to vary in the range 5.3–283.4 Bq L-1 with a mean value of 87 Bq L-1. Frequency distribution showed the 222Rn concentration in a large number of samples in the range of 0–50 Bq L-1. From the measured concentrations, the effective doses (lung and stomach) for the population of the region were estimated. The effective dose was found to vary from 42.6 to 2280.2 µSv y-1 with a mean value 702.5 µSv y-1. The effect of boiling of water showed a drastic reduction in the 222Rn concentration. The results of the present investigation are systematically analysed, compared with the literature values and discussed. [ABSTRACT FROM AUTHOR]

Polycrystalline hexagonal Yttrium Manganites (YMnO3) were prepared by solid-state route. X-ray studies revealed the formation of homogenous and single phase material in hexagonal structure. Dielectric, impedance, electrical, magnetic and magnetoelectric measurements were performed on the YMnO3 ceramics. Dielectric and impedance studies show relaxations near 200°C. Complex spectroscopic analysis, in the temperature range of 30–300°C from 1 kHz to 1 MHz, showed non-Debye relaxations. Ac and dc electrical measurements were extracted to understand the transport mechanism: Ac conductivity data is found to obey ‘Universal’ power law with exponent 0.8. Low temperature magnetization measurements were performed to understand the magnetic nature of the sample. Room temperature magnetoelectric (ME) measurements were also performed and corroborated with the magnetization data. [ABSTRACT FROM AUTHOR]

AC-impedance spectroscopic studies are carried out on lead magnesium niobate (PMN) and La-modified PMN-PT (lead magnesium niobate-lead titanate), Pb 1 - x La x [(Mg 1 + x / 3 Nb 2 - x / 3 ) 0.65 Ti 0.35( 1 - x / 4 ) ]O 3 , ceramic, with x = 0 to 0.07. Complex modulus and impedance plots exhibit two depressed semicircles and one depressed semicircle, respectively for PMN. This is attributed to the nearly same capacitance of grain and grain boundaries and higher grain boundary resistance than the grain resistance for PMN. Un-doped MPB composition of PMN-PT (0/65/35) and La-doped PMN-PT composition (7/65/35) also show similar complex modulus and impedance plots of PMN but in these samples the grain boundary capacitance was found to be higher than the grain capacitance. Cole-Cole plot shows two depressed semicircles, exhibiting grain and grain-boundary contributions in all the samples. La substitution is found to result in a broad peak in the frequency dependence of the imaginary part of the impedance and the modulus, for the temperature range 300–600°C. The maxima in the impedance and the modulus are found to shift towards higher frequencies with increasing temperature for all La-doped PMN-PT compositions, indicating a deviation from Debye behaviour. La-substitution results in broadening of the ε( T ) peak, and a marked frequency dependence of ε max (T max ), similar to that observed in PMN. It is believed that La-substitution induces the relaxor-like permittivity characteristics in MPB composition of PMN-PT by constructing higher-resistive and lower-capacitive grains, and grain boundaries. [ABSTRACT FROM AUTHOR]

The shelf stability of textured soya protein (TSP) procured from a single source and packaged in seven different packaging materials [viz. low density polyethylene (LDPE), HDPE, and polypropylene (PP) of 300 and 500 G and HDPE–LDPE–HDPE] in quantities of 10 kg each and stored at three different climatic conditions (viz hot and dry—Jodhpur; hot and humid—Tezpur; normal Mysore) for one year was studied. At the end of 6, 9, and 12 months, samples were drawn and analyzed for the quality parameters like moisture, browning, thiobarbituric acid reactive substances (TBARS), uric acid, water holding capacity (WHC), available lysine, in vitro digestibility, and sensory attributes. Anti nutritional factors like trypsin inhibitor activity (TIA) and phytic acid were also evaluated. The changes in the moisture content and non-enzymatic browning correlated well with the relative humidity of the place of storage. However the TBARS showed wide variations while the WHC varied between 2.6 and 2.9 of water/g material. Interestingly the TIA showed a ten-fold decrease (6.65 vs. 0.68 mg/g). The reduction in available lysine (6.33 vs. 5.29/16 g N) correlated well with the observed reduction in in vitro digestibility (84% vs. 73%). Although the sensory quality showed a decline by the end of 12 months storage period, the overall acceptability of the product on the 9 point Hedonic scale, remained very good. It is inferred from the present study that packaging of TSP in HDPE-500 Primary Sac and HDPE woven Secondary Sac, keeps the product shelf stable up to one year even under diverse climatic conditions. [ABSTRACT FROM AUTHOR]

In this article we investigate empirical Bayes procedures for estimates of binomial probabilities. We propose a sequential approach (vs. the usual fixed sample size) for estimation of p. The small sample behaviour of the proposed method is studied through a Monte Carlo experiment based on dataset applications drawn from carcinogenesis bioassays. Most of the conclusions are drawn from simulation studies which are themselves based on the applications. [ABSTRACT FROM AUTHOR]

This article studies the optimality and construction aspects of structurally incomplete row-column designs in which the number of non-empty nodes in rows and/or columns are unequal. Universal optimality of structurally incomplete row-column designs with unequal row and/or column sizes has been investigated. General methods of construction of universally optimal designs are obtained using pairwise balanced block designs and block designs with nested rows and columns. One method of construction gives SIRC design with equal row and equal column sizes. A method of construction of structurally incomplete row -- column designs for comparing test treatments with control treatment(s) is also given. [ABSTRACT FROM AUTHOR]

Glasses of various compositions in the system (100 - x )Li 2 B 4 O 7 - x (SrO-Bi 2 O 3 -Nb 2 O 5 ) (10 ≤ x ≤ 60) (in molar ratio) were prepared via a conventional melt-quenching technique. The glassy nature of the as-quenched samples was established by Differential Thermal Analyses (DTA). X-ray powder diffraction (XRD) and Transmission Electron Microscopic (TEM) studies confirmed the amorphous nature of the as quenched and crystallinity in the heat-treated samples. The formation of nanocrystalline layered perovskite SrBi 2 Nb 2 O 9 (SBN) phase, in the samples heat-treated at temperatures higher than 550°C, through an intermediate fluorite phase in the LBO glass matrix was confirmed by both the XRD and High Resolution Transmission Electron Microscopy (HRTEM). The samples that were heat-treated at two different temperatures, 550 and 625°C, (containing 0.35 and 0.47 μm sized SBN crystallites) exhibited broad dielectric anomalies in the vicinity of ferroelectric to paraelectric transition temperature of the parent SBN ceramics. A downward shift in the phase transition temperature was observed with decreasing crystallite size of SBN. The observation of pyroelectric and ferroelectric properties for the present samples confirmed their polar nature. [ABSTRACT FROM AUTHOR]

An experimental set up was fabricated to measure the pressure distribution on the seat pan and back-rest of a tractor seat. Experiments were conducted with four different seat pans having radius of curvatures of 60, 75, 90 and cm, four backrests with radius of curvatures of 30, 60, 90 and cm, and three back-rest inclinations of 0, 5 and 10 on representative Indian tractor operators. The subjective assessment of perceived comfort at the seat-operator interface was also recorded. Experiments were conducted in a randomized block design and the data obtained were analysed using suitable computer packages. Results indicate that all the parameters, namely seat pan, back-rest profile curvatures and the back-rest angle of inclination, affect the pressure distribution. It is concluded that a seat pan with radius of curvature 75cm, back-rest with radius of curvature 30 cm and back-rest inclination of 10 are the most suitable parameters for Indian tractor operators. [ABSTRACT FROM AUTHOR]

Investigates three small-area models. Nested-error regression model; Random regression coefficient model; Fay-Heriot model; Two-stage estimators; Second-order approximation to mean square error (MSE); Estimator of MSE approximation; Results of the Monte Carlo study; Efficiency of the two-stage estimators; Accuracy of the second-order approximation to MSE.

Objective. To describe requirements of physicians wishing to function as primary field emergency medical services (EMS) providers and variation of these requirements among states. Methods. A simple mailed survey was developed and distributed to all 50 U.S. state EMS directors. The survey gathered information about each state's regulations concerning physicians performing as a primary EMS crew member. Data were entered into a Microsoft Excel spreadsheet and reported using simple descriptive statistics, including proportions and 95% confidence intervals (CIs). Results. Forty-four (88%) of the states responded. In 32 states (73%), physicians can work as a primary member of either a basic life support (BLS) or an advanced life support (ALS) ambulance crew without any specific additional training. In 30 states (68%), physicians can work as a primary member of either a BLS or an ALS ambulance crew without any specific prehospital certification. All of the reporting states will allow a physician to become certified as an emergency medical technician (EMT) or paramedic and then work as a primary member of a BLS or ALS ambulance crew. Seventy-nine percent allow the provision of physician-level care on BLS ambulances, and 81% on ALS ambulances. There was no meaningful difference between the training requirements for becoming a certified BLS provider vs. a certified ALS provider. States were significantly less likely to require a skills examination of physicians wishing to become certified as a BLS provider (9%) compared with those wishing to become certified as an ALS provider (82%). Conclusion. Most states allow physicians to become certified prehospital care providers, although few states require physicians wishing to work as a primary EMS provider to do so, or even to undergo any specific EMS training. There is no national standardization of the preparatory requirements of physicians wishing to provide in-field EMS. [ABSTRACT FROM AUTHOR]

Mitoferrin 1 and mitoferrin 2 are homologous members of the mitochondrial solute carrier family. Mitoferrin 1 is required for mitochondrial iron delivery in developing erythrocytes. Here we show that mitoferrin 1 and mitoferrin 2 contribute to mitochondrial iron delivery in a variety of cells. Reductions in mitoferrin 1 and/or mitoferrin 2 levels by RNA interference result in decreased mitochondrial iron accumulation, heme synthesis, and iron-sulfur cluster synthesis. The ectopic expression of mitoferrin 1 in nonerythroid cells silenced for mitoferrin 2 or the expression of mitoferrin 2 in cells silenced for mitoferrin 1 restored heme synthesis to "baseline" levels. The ectopic expression of mitoferrin 2, however, did not support hemoglobinization in erythroid cells deficient in mitoferrin 1. Mitoferrin 2 could not restore heme synthesis in developing erythroid cells because of an inability of the protein to accumulate in mitochondria. The half-life of mitoferrin 1 was increased in developing erythroid cells, while the half-life of mitoferrin 2 did not change. These results suggest that mitochondrial iron accumulation is tightly regulated and that controlling mitoferrin levels within the mitochondrial membrane provides a mechanism to regulate mitochondrial iron levels. [ABSTRACT FROM AUTHOR]