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We report an enhanced magnetoelectric (ME) effect in spin–phonon coupled single-phase La1−xSmxYFe2O6 (0 ≤ x ≤ 1). The structural, electric, magnetic, and ME properties have been investigated to establish their interplay leading to magnetoelectricity. X-ray diffraction study suggests the facilitation of the P21nm phase (double perovskite lattice arrangements) formation and improved structural order due to the substitution of Sm in the lattice. Antiferromagnetic (AFM) transition ∼700 K along with a spin-reorientation transition around room temperature (RT) and below is observed in the thermomagnetic curve. The indication of short range ordering in the magnetization data in the form of a non-Griffiths-like phase (nGP) is observed. The short range ordering could be minimized along with consequent improvement in AFM ordering, due to Sm substitution. An enhanced (∼31% with respect to x = 0) RT first-order ME coupling coefficient ∼0.59 mV cm−1 Oe−1 in x = 0.75 composition is observed. The findings reported here open the door to exercise spin-reorientation transition in the spin–phonon coupled double perovskites for spintronic device applications. [ABSTRACT FROM AUTHOR]

BACKGROUND/OBJECTIVES: Data on performance of QuantiFERON-TB Gold In-Tube test (QFT) and tuberculin skin test (TST) in children with active tuberculosis from high burden countries in the context of micronutrient deficiency are scarce. The objective of this study was to evaluate the effect of micronutrient deficiency on the performance of TST and QFT in children with intrathoracic tuberculosis. SUBJECTS/METHODS: Children with probable intrathoracic tuberculosis underwent TST, QFT, gastric lavages and induced sputum examination for AFB (Acid-Fast Bacilli) smear and culture. Zinc, copper, ferritin and vitamin D were measured on stored serum samples. The study used cross-sectional data at initiation of anti-tubercular therapy. RESULTS: Three hundred and sixty-two children (median age 115.5 months (interquartile range: 73, 144), 200 (55.3%) girls) were enrolled in the study. Microbiological confirmation of tuberculosis could be obtained in 128 patients. TST and QFT were positive in 337 (93%) and 297 (82%) children, respectively. Performance of both the tests was unaffected by weight-for-age and height-for-age 'z-scores' or by serum copper levels. TST was not affected by serum zinc and ferritin levels. Children with negative QFT results had lower mean serum zinc level (P = 0.01) and higher ferritin levels (P = 0.007) as compared to those with positive test. Higher proportion of children with positive TST were vitamin D deficient/insufficient (P = 0.003). CONCLUSION: Micronutrient status, especially serum levels of zinc, may influence the performance of QFT in children with intrathoracic tuberculosis. Considering the high prevalence of zinc deficiency in developing countries, QFT should be used cautiously for diagnosing tuberculosis. European Journal of Clinical Nutrition (2014) 68, 38-42; doi: 10.1038/ejcn.2013.216; published online 30 October 2013 Keywords: pediatric tuberculosis; tuberculin skin test; interferon gamma release assay; zinc deficiency; vitamin D status, INTRODUCTION Childhood tuberculosis (TB) is a common cause of morbidity in developing countries. It is a challenging disease, difficult to diagnose, as the gold standard diagnostic test of demonstration of [...]

Security solutions of stereo images are always a major concern during the transmission and communication. In this manuscript, a simple yet efficient framework for encrypting stereo images is formulated using discrete cosine transform (DCT), generalized logistic map, Schur decomposition and magic square method. The framework initiated with the integration of DCT and generalized logistic map to unify both pair of images. This unified image is then encrypted using the Schur decomposition and magic square method. The various experiments and analysis have been done to explore the validity, proficiency and performance of the purport framework. [ABSTRACT FROM AUTHOR]

In the present work, a ternary Heusler alloy of composition Ni50Mn40Sn10 with a high martensitic transformation temperature has been prepared by arc-melting technique. The crystal structure of the obtained alloy is investigated by X-ray diffraction. The microstructure of the specimen sintered at 950°C for 72 h followed by ice-water quenching shows needle-like martensitic structure. Energy dispersive spectroscopy is utilized for compositional study. The differential scanning calorimetry result shows that the alloy undergoes a martensitic transformation at 190°C upon cooling. The M-H curve suggests paramagnetic nature of the martensite phase at room temperature. The present alloy system has a great potential to be used for high-temperature shape memory applications. Experimental data of this study may be useful for developing Ga-free high-temperature shape memory alloys. [ABSTRACT FROM AUTHOR]

Drug abuse and addiction is one of the great evils of our time. It has become a serious problem in India. Young and old alike everywhere are addicted lo drugs. has resulted in increased crime, tension, disease, horror and lack of peace and security. The cities have attracted large number of youth who come in search of employment. Such people live a lonely and isolated life and become anti-social. They fall into evil company and get addicted. The children who arc deprived of the loving care and affection, and do not get right type of education are prone to be addicted to drugs. [ABSTRACT FROM AUTHOR]

Graphene (GR) attracts increasing attention due to its unique physical and chemical properties, thus potential applications in optics and electronics. However the gapless band structure greatly limits its wide applications in optoelectronic devices. Surface functionalisation proves to be an effective method to tune the properties of graphene. In this study, hybrid GR materials with enhanced properties were achieved through GR surface functionalisation by using aryl diazonium salts of photosensitive azobenzene. Conformational transition from trans to cis states of azobenzenes induces hole doping in graphene through charge transfer. Significantly different from the pristine graphene, the graphene-azobenzene hybrids exhibited strong photoisomerisation of azobenzene between cis and trans forms under UV and visible light illumination. The large photoresponse obtained from the functionalised GR could be ascribed to the rigid chemical environment with azobenzene moieties chemically bonded onto the GR surface. Such surface functionalised GR hybrids with unique optical properties position them as promising materials for optoelectronic devices. [ABSTRACT FROM AUTHOR]

As novel fibers with enhanced mechanical properties continue to be synthesized and developed, the ability to easily and accurately characterize these materials becomes increasingly important. Here we present a design for an inexpensive tabletop instrument to measure shear modulus (G) and other longitudinal shear properties of a micrometer-sized monofilament fiber sample, such as nonlinearities and hysteresis. This automated system applies twist to the sample and measures the resulting torque using a sensitive optical detector that tracks a torsion reference. The accuracy of the instrument was verified by measuring G for high purity copper and tungsten fibers, for which G is well known. Two industrially important fibers, IM7 carbon fiber and Kevlar® 119, were also characterized with this system and were found to have G = 16.5 ±2.1 and 2.42 ± 0.32 GPa, respectively. [ABSTRACT FROM AUTHOR]

Despite their wide spread applications, the mechanical behavior of helically coiled structures has evaded an accurate understanding at any length scale (nano to macro) mainly due to their geometrical complexity. The advent of helically coiled micro/nanoscale structures in nano-robotics, nano-inductors, and impact protection coatings has necessitated the development of new methodologies for determining their shear and tensile properties. Accordingly, we developed a synergistic protocol which (i) integrates analytical, numerical (i.e., finite element using COMSOL®) and experimental (harmonic detection of resonance; HDR) methods to obtain an empirically validated closed form expression for the shear modulus and resonance frequency of a singly clamped helically coiled carbon nanowire (HCNW), and (ii) circumvents the need for solving 12th order differential equations. From the experimental standpoint, a visual detection of resonances (using in situ scanning electron microscopy) combined with HDR revealed intriguing non-planar resonance modes at much lower driving forces relative to those needed for linear carbon nanotube cantilevers. Interestingly, despite the presence of mechanical and geometrical nonlinearities in the HCNW resonance behavior the ratio of the first two transverse modes f2/f1 was found to be similar to the ratio predicted by the Euler-Bernoulli theorem for linear cantilevers. [ABSTRACT FROM AUTHOR]

We report an enhanced magnetoelectric (ME) effect in spin–phonon coupled single-phase La1−xSmxYFe2O6 (0 ≤ x ≤ 1). The structural, electric, magnetic, and ME properties have been investigated to establish their interplay leading to magnetoelectricity. X-ray diffraction study suggests the facilitation of the P21nm phase (double perovskite lattice arrangements) formation and improved structural order due to the substitution of Sm in the lattice. Antiferromagnetic (AFM) transition ∼700 K along with a spin-reorientation transition around room temperature (RT) and below is observed in the thermomagnetic curve. The indication of short range ordering in the magnetization data in the form of a non-Griffiths-like phase (nGP) is observed. The short range ordering could be minimized along with consequent improvement in AFM ordering, due to Sm substitution. An enhanced (∼31% with respect to x = 0) RT first-order ME coupling coefficient ∼0.59 mV cm−1 Oe−1 in x = 0.75 composition is observed. The findings reported here open the door to exercise spin-reorientation transition in the spin–phonon coupled double perovskites for spintronic device applications. [ABSTRACT FROM AUTHOR]

Abstract: The Plains CO2 Reduction (PCOR) Partnership, led by the Energy & Environmental Research Center, is working with Denbury Onshore LLC (Denbury) to characterize and monitor a large-scale CO2 enhanced oil recovery (EOR) and CO2 storage project at the Bell Creek oil field located in southeastern Montana, USA. Denbury owns and operates the field and will carry out the commercial EOR project. The PCOR Partnership is applying an integrated approach to site characterization, modeling, predictive simulation, risk assessment, and monitoring to improve understanding of the interrelationship between CO2 storage and EOR in a clastic reservoir. [Copyright &y& Elsevier]

Abstract: This simulation study evaluates ways for maximizing incremental oil recovery (IOR) and CO2 storage capacity for a current simultaneous enhanced oil recovery (EOR) and CO2 storage project at the Zama oil field F Pool situated in northwestern Alberta, Canada. The results clearly indicate the viability of formation water extraction for increasing storage capacity in a closed geological structure. An approximately fivefold increase in CO2 storage capacity was observed, if current EOR is coupled with bottom water extraction. IOR of 22.1% in the next 20 years can be achieved, which is 5% more than continuing current EOR without bottom water extraction. [Copyright &y& Elsevier]

Abstract: The Energy & Environmental Research Center has conducted an analysis of formation water extraction from carbon dioxide (CO2) storage reservoirs under joint sponsorship from the IEA Greenhouse Gas R&D Programme and the U.S. Department of Energy. The work included a survey of geologic and water quality conditions of deep saline formations, selection of four case study sites representing a wide range of these geologic and water quality conditions, and a study of the impacts of formation water extraction on CO2 storage and the potential for the beneficial use of extracted water at these sites. [Copyright &y& Elsevier]

Background and Objectives: "In all things of nature there is something of the marvelous." In the present study the anti-hyperglycemic and anti-oxidative potential of aqueous extract of Trigonella foenum graceum (TFG), a traditional medicinal herb was assessed in liver and WBC of alloxan induced diabetic rats. Free radicals can cause oxidative damage, which is balanced by the antioxidants. This has been implicated in aging, and diseases such as diabetes and other chronic conditions. Material and Methods: TFG extract was administered orally [500 (LM) and 1000 mg/kg body weight (HM)] for six weeks. The effect of TFG on blood glucose were studied and the levels of lipid peroxidation [MDA (Malondialdehyde)] and antioxidant enzymes [SOD (Superoxide dismutase), GPx (Reduced Glutathione peroxidase)] were estimated and compared with standard drugs glibenclamide and insulin. Results: Treatment with TFG, insulin and glibenclamide resulted in significantly reduced blood glucose in LM (8.71%) and HM (3.87%) in comparison with normal controls. There was a significant decrease in lipid peroxidation in liver and white blood cells (WBC) in both low and high doses [liver LM (49%), HM (57.25%)], [WBC LM (54.28%), HM (62.5%)] and increase in antioxidant enzymes SOD [liver LM (33.59%), HM (58.7%)] [WBC LM (44.9%)] HM (58.7%) and GPx [Liver LM (58.55%), HM (40.20%)], [WBC LM (55.46%), HM (56.4%)] when compared to diabetic controls. Discussion: Potency of TFG in restoring several parameters to normal values is comparable to glibenclamide, though not as efficient as insulin, an indication of its antihyperglycemic and antioxidant effect. [ABSTRACT FROM AUTHOR]

In this paper we discuss code assignment schemes in wideband code division multiple access (WCDMA) systems based on orthogonal variable spreading factor (OVSK) codes. The OVSK codes are the limited resources in the forward link and their usage is critical for higher efficiency. The paper described single code and multi code schemes for different requirements, In single code assignment category, adaptive code assignment (ADA) uses arrival distribution to reduce the number of code searches prior to finding a vacant candidate code. The time multiplexing in single code design makes code blocking zero with additional time slot management requirement. It provides additional benefit of handling non-quantized data rates. The next code precedence high (NCPH) scheme uses precedence numbers to make code assignment compact. The multi code scheme uses multiple code to handle each call. Two multi code schemes are described, one aims to reduce complexity and the other aims to minimize code scattering and code blocking. The simulation results are demonstrated to show the number of code searches and call blocking variation for various code assignment schemes. [ABSTRACT FROM AUTHOR]

A nose-only inhalation exposure system (NOIES) was evaluated for its performance in this study using test polystyrene latex spheres (PLS) and ectromelia virus (ECTV), which is a surrogate for variola virus, the causative agent of smallpox. The test aerosol sampled at the various ports of the NOIES was found to be consistent in particle size and number concentration. ECTV bio-aerosol was delivered to A/J mice strain and the lethal dose (LD50) value at which mortality was 50% was found to be 41 PFU/mL. The airborne ECTV particles were sampled and collected on TEM grids for particle size imaging using a scanning electron microscope (SEM) and structural integrity imaging using a transmission electron microscope (TEM). SEM images of ECTV after aerosolization showed the virions to be coated with the smaller size solute particles generated from the buffer solution during the aerosolization process. TEM images showed the ECTV to be structurally intact after undergoing the process of aerosolization. From the viable ECTV particle size distribution, the geometric mean diameter (GMD) of the airborne ECTV particles was calculated to be 278 nm with a geometric standard deviation (GSD) of 1.73. [ABSTRACT FROM AUTHOR]

A portable free-fall electrostatic separator capable of analyzing gram quantities of charged powders is presented. Unlike a Faraday pail, in which only the net average charge-to-mass (Q/M) ratio of the particles sampled by the instrument is measured, an electrostatic separator is capable of separately measuring the charge-to-mass ratios of positively and negatively charged sampled powders. Thus, with an electrostatic separator it is possible to measure the mass fractions of powders that are charged with different polarities and the respective charge-to-mass ratios, along with the mass fraction of particles that are uncharged or charged below a threshold level. We describe a method of measuring the total charge of the collected particles in real time by incorporating an electrometer to integrate the current flowing through the collecting electrode to the high voltage power supply. In this manner, both the total charge and total mass of powder deposited on the two electrodes are measured in near real time, providing information on charge-to-mass ratio of the aerosol cloud sampled. Such real time measurements are often needed to analyze the electrostatic charging properties of small quantities of dispersed powder, particularly in such applications where the charge characteristics are of high importance. [ABSTRACT FROM AUTHOR]

In the hilly areas of eastern Gujarat, western Madhya Pradesh and southern Rajasthan, in western India, farmers are very resource-poor and cultivate small and fragmented land holdings. Maize is their main rainy season (kharif) cereal and it is grown as a rainfed crop in low-fertility fields, often on sloping land that is vulnerable to soil erosion. Its productivity is very low, averaging below 1 t ha−1. New farm technologies to increase this productivity have to be low cost to be attractive to farmers who have limited access to purchased inputs and few means to purchase them. From observations of local farming practices, intercropping of maize with legumes was identified as an attractive option because the only additional input needed is seed of the legume crop. Participatory research was conducted on intercropping of maize with improved varieties of horsegram (Macrotyloma uniflorum). Many farmers who tried this intercropping adopted it in subsequent years, while others preferred to grow the new horsegram varieties as a sole crop. Farmers reported that less weeding was required in the intercrop as the horsegram smothered weeds. All farmers used the dry stover from the horsegram as a fodder for their animals. Farmers used the whole seed as dal, which provided additional protein in their diet. Farmers also sold the grain, but it fetched a low price in the poorly developed market for horsegram. Previously intercropping had been tried with local landraces, but the acceptance of intercropping was higher with new varieties such as AK-42 that yielded over 60% more grain. Participatory trials in which only one entry was compared with the local variety did not show a difference between AK-21 and AK-42 as in all cases both were preferred over the local variety. When they were directly compared with each other, farmers' perceptions showed a significant preference for AK-42. Variety IVH-2 was found to be better than AK-42: it matured 15 days earlier, better matching the maturity of the maize, had superior grain quality and yielded about the same. The greater uptake of improved horsegram varieties for sole and intercropping is likely to be limited by the lack of seed supply. [ABSTRACT FROM PUBLISHER]

Carbon nanostructures represent a revolution in science and hold the potential for a large range of applications because of their interesting electrical, mechanical, and optical properties. Multiwall carbon nanotubes and carbon nanofibers of herringbone formation were grown by chemical vapor deposition on different catalysts from a number of hydrocarbon sources. After the total or particle removal of the catalyst system, the carbon nanostructures were analyzed for hydrogen uptake. Six samples of nanofibers grown on a Pd-based catalyst system (with a surface area of 425-455 m2/g) were controlled oxidized in air, such that they had different ratios of Pd/C varying from 0.05 to 0.9 mole ratio. The hydrogen uptake experiments were performed volumetrically in a Sievert-type installation and showed that the quantity of desorbed hydrogen (for pressure intervals ranging from 1 to 100 bars) by the carbon nanostructures free of any metal catalyst particles was between 0.04 and 0.33% by weight. For the samples of nanofibers that contained Pd in various Pd/C ratios, palladium revealed catalytic properties and supplied atomic hydrogen at the Pd/C interface by dissociating the H2 molecules. The results show a direct correlation between the Pd/C ratio and the quantity of hydrogen absorbed by these samples. A saturation value of about 1.5 wt.% was reached for a high ratio of about 1:1 of Pd/C. The multiwall carbon nanotubes grown on a Fe:Co:CaCO3 catalytic system and purified by acid cleaning and air oxidation showed a hydrogen uptake value of 0.1 to 0.2 wt.%. [ABSTRACT FROM AUTHOR]