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Aims: Earlier comparisons of cognitive impairment among patients with bipolar disorder and schizophrenia have found a largely similar profile of deficits, but results have varied between studies. This prompted the current attempt at another such comparison. Methods: Executive functions, memory, IQ, attention–concentration and perceptuomotor function were assessed in 48 bipolar disorder patients with operationally defined euthymia, and compared with 32 schizophrenia patients in remission, and 23 normal controls. Comparisons were re-attempted after controlling for years of schooling and residual affective symptoms. Results: Uncontrolled comparisons indicated that, compared to controls, both bipolar disorder and schizophrenia patients were significantly impaired on different tests of executive function, memory, IQ and perceptuomotor functions. Controlling for years of schooling and residual affective symptoms, however, served to remove most of the differences between patients and controls, apart from some aspects of executive function in schizophrenia and memory impairment in both schizophrenia and bipolar disorder. Patients with schizophrenia consistently performed worse than patients with bipolar disorder, but none of the differences between schizophrenia and bipolar disorder were significant. Conclusions: Patients with bipolar disorder exhibit cognitive difficulties that are very similar to schizophrenia in terms of their profile, although patients with schizophrenia may have more severe and widespread impairments. The resemblance in cognitive profiles has important implications for the etiology and treatment of both disorders. [ABSTRACT FROM AUTHOR]

Abstract: Acidithiobacillus ferrooxidans biofilm grown on uranium ore substrate was analyzed by a micro-Raman spectrometer and an atomic force microscope (AFM). The bacterium employed for this study, A. ferrooxidans BM1, was isolated from a uranium mine (Jaduguda, India). Micro-Raman analysis revealed the different constituents of molecular fragments present in microbial cells and in secreted extracellular polymeric substances (EPSs). AFM images clearly revealed bacterial cells surrounded by EPS. From Raman spectral data, the composition of EPS from A. ferrooxidans BM1 appeared to be similar to that of EPS secreted in a different Pseudomonas bacterium. [Copyright &y& Elsevier]

A numerical modeling framework for planar solid-oxide fuel cell (PSOFC) based vehicular auxiliary power unit (APU) is developed. The power-conditioning system (PCS) model comprises the comprehensive transient models of PSOFC, balance-of-plant and power-electronics subsystems (BOPS and PES, respectively) and application load (AL). It can be used for resolving the interactions among PSOFC, BOPS, PES and AL, control design and system optimization and studying fuel-cell durability. The PCS model has several key properties including: (i) it can simultaneously predict spatial as well as temporal dynamics; (ii) it has two levels of abstraction: comprehensive (for detailed dynamics) and reduced-order (for fast simulation) and (iii) the fast-simulation model can be implemented completely in Simulink/Matlab environment, thereby significantly reducing the cost as well as time and provides the avenue for real-time simulation and integration with vehicular power-train models employing the widely used ADVISOR. The computational overhead and accuracy of the fast-simulation and comprehensive models are compared. Significant savings in time compared to using the former were obtained, without compromising accuracy. [ABSTRACT FROM AUTHOR]

Abstract: Oscillator strengths (f), line strengths (S) and radiative decay rates (A) are presented for all 1s–2p transitions in gold (Au) ions. X-ray emission from gold is extensively used, such as in fusion experiments, and in medical research for diagnostics and treatment. The 1s–2p transitions in gold are found to be in the hard X-ray region of 66–73keV (0.1888–) and are limited to from hydrogen-like to fluorine-like ions as the 2p subshell is filled beyond fluorine. While there are two 1s–2p transitions (– and –) for hydrogen-like gold, , the number varies depending on the number of electrons in the 2p subshell before and after the transition. For example, there are 35 1s–2p transitions giving the same number of lines for carbon-like Au, . The transitions can be of both types, dipole allowed and intercombination, and are in general strong, that is, . However, there are also weak transitions in the set. The present results are obtained from configuration interaction atomic structure calculations using the code SUPERSTRUCTURE which includes relativistic effects in Breit–Pauli approximation. The results have been benchmarked for a few ionic states with other detailed relativistic approaches, such as Dirac–Fock and coupled cluster. Comparisons with the very few transitions in the literature as well as those from other approaches indicate reasonable accuracy for the present results. [Copyright &y& Elsevier]

Genetic diversity among 56 'new plant type' lines including four improved cultivars was studied using Mahalanobis D² statistic under shallow lowland ecosystem. The genotypes were grouped into 11 clusters showing fair degree of relationship between geographic distribution and genetic divergence. Cluster 1 with 23 genotypes was the largest followed by cluster IV with 12, cluster VII with 10 genotypes, and cluster IX with 4 genotypes, while cluster II, III, V, VII, VIII, X, and XI were monogenotypic. Genotypes in cluster IX had highest intra-cluster distance followed by cluster IV and VII while highest inter cluster divergence was between cluster VII and XI followed by that between VI and XI. Maturity duration contributed maximum to the total divergence. Other traits with appreciable contribution to total divergence were spikelet per panicle (no.), grain filling (%), panicle number/m², panicle length (cm), and harvest index (%). All the minimum and maximum cluster mean values were distributed in relatively distant clusters. The members of clusters VIII, V, IV VI, X, VI, and I may be further evaluated, as these clusters are observed to possess high cluster mean for grain yield. Further, it is suggested that cross combinations of 1R73964-120-5-3-2 x 17214-110- 1-2, 1R73964-120-5-3-2 x IR72967-12-2-3, 1R75282-58-1-2-3 x IR71701- 28-1-4-3, IR75268-45-2-5-3 x 171676-106-10-3, IR75282-58- 1-2-3 x 1R72967-12-2-3, and 1R73964-120-5-3-2 x IR7l701-28-1-4 showing high D² matrix value are expected to produce superior progenies. [ABSTRACT FROM AUTHOR]

This paper presents an efficient technique for synthesis and optimization of the polynomials over GF(2m), where m is a nonzero positive integer. The technique is based on a graph-based decomposition and factorization of the polynomials, followed by efficient network factorization and optimization. A technique for efficiently computing the coefficients of the polynomials over GF(pm), where p is a prime number, is first presented. The coefficients are stored as polynomial graphs over GF(pm). The synthesis and optimization is initiated from this graph-based representation. The technique has been applied to minimize multipliers over the fields GF(2κ ), where k = 2,..., 8, generated with all the 51 primitive polynomials in the 0.18-/~m CMOS technology with the help of the Synopsys design compiler. It has also been applied to minimize combinational exponentiation circuits, parallel integer adders and multipliers, and other multivariate bit- as well as word-level polynomials. The experimental results suggest that the proposed technique can reduce area, delay, and power by significant amounts. We also observed that the technique is capable of producing 100% testable circuits for stuck-at faults. [ABSTRACT FROM AUTHOR]

Lepcha is the oldest and the first tribe reported from Sikkim, India; majority of its population inhabiting in Dzongu valley, an officially demarcated reserve for Lepcha community, bordering Khangchendzonga Biosphere Reserve, in north district. Lepchas of Dzongu are known for their retention of rich cultural heritage. In view of the on-going cultural and economic changes brought in by the process of globalization, the immediate need was felt to document in details the underexplored ethnomedicinal practices of Lepchas of Dzongu valley. This paper reports 118 species, belonging to 71 families and 108 genera, under ethnomedicinal utility by the Lepchas for curing approximately 66 ailments, which could be grouped under 14 broad categories. Zingiberaceae appeared as the most used family (8 species and 5 genera). As per use pattern, maximum of 30.50% species are to cure stomach related disorders/ailments, followed by 19.49% for curing cut, wounds, inflammation, sprains and joint pains. Administration of medicine orally is recorded in 75% cases. Root and rhizome harvesting targeted 30 species. The changing scenario over time both at sociocultural front and passing traditional knowledge interests from older to younger generation and rich ethnomicinal wealth of the oldest tribe of Sikkim are discussed in the light of conservation strategies and techniques to adopt. [ABSTRACT FROM AUTHOR]

In this paper, a cumulative-sum-based fault detection algorithm is proposed for the power system relaying application. Literature suggests the successful application of this method to process control systems where the deviation of parameters is tracked to indicate any abnormal conditions. The effectiveness of the algorithm is found to be better than the traditional methods in the presence of noise, system frequency deviation, and other uncertainties. It is also not affected by load change in a system. Above all, it provides relatively higher index values without compromising detection speed. [ABSTRACT FROM AUTHOR]

When a remotely sited wind farm is connected to the utility power system through a distribution line, the overcurrent relay at the common coupling point needs a directional feature. This paper presents a method for estimating the direction of fault in such radial distribution systems using phase change in current. The difference in phase angle between the positive-sequence component of the current during fault and prefault conditions has been found to be a good indicator of the fault direction in a three-phase system. A rule base formed for the purpose decides the location of fault with respect to the relay in a distribution system. Such a strategy reduces the cost of the voltage sensor and/or connection for a protection scheme which is of relevance in emerging distributed-generation systems. The algorithm has been tested through simulation for different radial distribution systems. [ABSTRACT FROM AUTHOR]

The nanocrystalline fine powders (∼80 nm) of (Ba1− x La x )(Fe2/3W1/3)1− x/4O3, (BLFW) ( x = 0.0, 0.05, 0.10 and 0.15) were synthesized with a combined mechanical activation and conventional high-temperature solid-state reaction methods. Preliminary X-ray structural analysis of pellet samples (prepared from fine powders) showed formation of a single-phase tetragonal system. Detailed studies of dielectric properties (εr and tan δ) exhibit that these parameters are strongly dependent on frequency, temperature and La composition. The La-substitution increases the dielectric constant and decreases the tan δ up to 10% substitutions of La at the Ba-site, and then reversed the variation, and hence this composition is considered as a critical composition. This observation was found valid for structure, microstructures, dielectric constant, electrical conductivity, J– E characteristics and impedance parameters also. Like in other perovskites (PZT, BZT), La substitution plays an important role in tailoring the properties of Ba(Fe2/3W1/3)O3 ceramics. [ABSTRACT FROM AUTHOR]

This paper presents a technique for representing multiple-output binary and word-level functions in CF(N) (where N = pm, p is a prime number, and m is a nonzero positive integer) based on decision diagrams (DDs). The presented DD is canonical and can be made minimal with respect to a given variable order. The DD has been tested on benchmarks, including integer multiplier circuits, and the results show that it can produce better node compression (more than an order of magnitude in some eases) compared to shared binary DDs (BDDs). The benchmark results also reflect the effect of varying the input and output field sizes on the number of nodes. Methods of graph-based representation of characteristic and encoded characteristic functions in GF(N) are also presented. Performance of the proposed representations has been studied in terms of average path lengths and the actual evaluation times with 50,000 randomly generated patterns on many benchmark circuits. All of these results reflect that the proposed technique can outperform existing techniques. [ABSTRACT FROM AUTHOR]

This paper presents the generalized theory and an efficient graph-based technique for the calculation and representation of coefficients of multivariate canonic polynomials over arbitrary finite fields in any polarity. The technique presented for computing coefficients is unlike polynomial interpolation or matrix-based techniques and takes into consideration efficient graph-based forms which can be available as an existing resource during synthesis, verification, or simulation of digital systems. Techniques for optimization of the graph-based forms for representing the coefficients are also presented. The efficiency of the algorithm increases for larger fields. As a test case, the proposed technique has been applied to benchmark circuits over GF(2m). The experimental results show that the proposed technique can significantly speed up execution time. [ABSTRACT FROM AUTHOR]

Abstract: Vasomotion refers to spontaneous variations in the lumen size of small vessels, with a plausible role in regulation of various aspects of microcirculation. We propose a computational model of vasomotion in skeletal muscle in which the pattern of vasomotion is shown to critically determine the efficiency of oxygenation of a muscle fiber. In this model, precapillary sphincters are modeled as nonlinear oscillators. We hypothesize that these sphincters interact via exchange of vasoactive substances. As a consequence, vasomotion is described as a phenomenon associated with a network of nonlinear oscillators. As a specific instance, we model the vasomotion of precapillary sphincters surrounding an active fiber. The sphincters coordinate their rhythms so as to minimize oxygen deficit in the fiber. Our modeling studies indicate that efficient oxygenation of the fiber depends crucially on the mode of interaction among the vasomotions of individual sphincters. While chaotic forms of vasomotion enhanced oxygenation, regular patterns of vasomotion failed to meet the oxygenation demand accurately. [Copyright &y& Elsevier]

Abstract: The polycrystalline samples of La-modified Bi(Sc1/2Fe1/2)O3 (i.e., (Bi1−x La x )(Sc1/2Fe1/2)O3) were prepared using a solid-state reaction technique. The formation of single-phase compound was checked with an X-ray diffraction (XRD) technique. A small amount of La-substitution (0≤ x ≤0.15) at the Bi site does not change the crystal structure of Bi(Sc1/2Fe1/2)O3. Detailed studies of dielectric properties (i.e., dielectric constant, loss tangent and ac conductivity) showed significant effect of La doping on these properties. High dielectric constant with relatively low loss tangent and electrical conductivity of the mixed-type (i.e., space charge and oxygen ion vacancies) are some of the special features of the La-modified Bi(Sc1/2Fe1/2)O3 compounds. [Copyright &y& Elsevier]

For a planar solid-oxide fuel cell (PSOFC)-based power system, the differences in the response times of the PSOFC stack, the power electronics subsystem (PES), and the balance-of-plant subsystem (BOPS) cause low-reactant conditions near the PSOFC electrodes during load transients. Because the BOPS cannot instantaneously provide enough fuel to the PSOFC, the load transients have a detrimental effect on the performance and life of the fuel cell. To alleviate the degrading effects of load transients on PSOFC stacks, the effectiveness of the energy buffering is investigated. [ABSTRACT FROM AUTHOR]

One-year-plus age groups (yearlings) of Indian major carps (IMC) were artificially infected with the epizootic ulcerative syndrome (EUS) pathogen, Aphanomyces invadans and detailed sequential inflammatory response against the pathogen was delineated. For comparison, the corresponding age groups of EUS-resistant (common carp, CC) and susceptible (snakehead) fish species were used in the artificial infection experiments. In all the fish species the injected spores were able to germinate, but in susceptible fish species the germinated hyphae were able to proliferate massively and cause extensive necrotic pathology leading to severe gross lesions. On the other hand, in IMC and CC, the germinated hyphae were prevented from significant proliferation and spreading to the neighbouring tissues and the lesion area was healed over the experimental period of 15 days and no gross visible lesion was observed. Higher number of inflammatory cells and more efficient epithelioid cell layer formation are believed to play an important role in the defence mechanism of yearlings of IMC and CC against A. invadans infection. [ABSTRACT FROM AUTHOR]

Abstract: The polycrystalline nanoceramics (∼60nm) of Ca(Fe2/3W1/3)O3 (CFW) were synthesized by mechanochemical and solid-state reaction techniques. Preliminary X-ray structural analysis of CFW suggested the formation of single-phase compound in tetragonal crystal system (distorted structure of ideal perovskite). The large distortion (∼16%) is supported by a large deviation of tolerance factor t=0.86 from unity (for ideal perovskite). The SEM micrograph shows the polycrystalline nature of the sample with different grain sizes, which are inhomogeneously distributed through the sample surface. Detailed studies of dielectric and impedance properties of the material in a wide range of frequency (1kHz–1MHz) and temperatures (300–630K) show that these properties are strongly temperature and frequency dependent. The nature of variation of AC conductivity exhibits a progressive increase in AC conductivity on increasing temperature. The oxygen vacancies, space charge and mobile charge carriers play an important role in relaxation and conduction process. The relaxation process in the material was found to be of non-Debye type. [Copyright &y& Elsevier]

Stereoselective and regioselective synthesis of functionalized seven- and eight-membered carbocyclic systems was achieved by the ring expansion-cleavage of readily prepared [3.2.1] and [3.3.1] bicyclic alcohols using alkoxy radical fragmentation at room temperature. Transannular migration in the cyclooctane �system explain formation of unusual products. [ABSTRACT FROM AUTHOR]

The increasing demand of ready-to-eat poultry products has led to serious concerns over product safety, and more emphasis has been placed on thorough cooking of products. In this study, processing conditions and thermal inactivation of Listeria innocua in chicken breast meats were evaluated during convection cooking in a pilot-plant scale air-steam impingement oven. A predictive model was developed by integrating heat and mass transfer models with a pathogen kinetics model to predict temperature, water content, product yield, and bacterial inactivation during air-steam impingement cooking. Skinless boneless chicken breasts were cooked at oven air temperatures of 177 and 200°C for 2 to 10 min at a humidity of 70 to 75% (moisture by volume) and an air velocity of 1 m/s at the exit of the nozzles. The reduction in Listeria in chicken breasts after 2 to 5 min of cooking was from 0.3 to 1.4 log CFU/g and from 0.8 to 1.8 log CFU/g at 177 and 200°C, respectively. After cooking for 10 min at both temperatures, no survivors were detected in any of the cooked chicken breasts from an initial bacterial concentration of 106 CFU/g. The standard errors of prediction for the endpoint center temperatures after 2 to 10 min of cooking were 2.8 and 3.0°C for air temperatures of 177 and 200°C, respectively. At 177 and 200°C, the median relative errors of prediction for water content were 2.5 and 3.7% and those for product yield were 5.4 and 8.4%, respectively. The developed model can be used as a tool to assist in evaluating thermal processing schedules for poultry products cooked in an air-steam impingement oven. [ABSTRACT FROM AUTHOR]

Wind speed varies continuously throughout a day resulting in fluctuating wind farm output power. When such a farm is connected to the grid through a line, the transmitted power and the relay end voltage (with respect to grid voltage) fluctuate continuously. In this paper, the protection of such a line with distance relay is investigated. The ideal trip characteristic for distance relay is studied with change in conditions of the wind farm. A method is proposed to set the boundary adaptively using local information only. [ABSTRACT FROM AUTHOR]

We present the first results from the low-energy detector payload of the solar X-ray spectrometer (SOXS) mission, which was launched onboard the GSAT-2 Indian spacecraft on May 08, 2003 by the GSLV-D2 rocket to study solar flares. The SOXS low-energy detector (SLD) payload was designed, developed, and fabricated by the Physical Research Laboratory (PRL) in collaboration with the Space Application Centre (SAC), Ahmedabad and the Indian Space Research Organization (ISRO) Satellite Centre (ISAC), Bangalore. The SLD payload employs state-of-the-art, solid-state detectors, viz., Si PIN and Cadmium-Zinc-Telluride (CZT) devices that operate at near room temperature (−20 °C). The energy ranges of the Si PIN and CZT detectors are 4 – 25 and 4 – 56 keV, respectively. The Si PIN provides sub-keV energy resolution, while the CZT provides ~1.7 keV energy resolution throughout the energy range. The high sensitivity and sub-keV energy resolution of the Si PIN detector allows measuring the intensity, peak energy, and the equivalent width of the Fe-line complex at approximately 6.7 keV, as a function of time in all ten M-class flares studied in this investigation. The peak energy ( E p) of the Fe-line feature varies between 6.4 and 6.7 keV with increase in temperature from 9 to 58 MK. We found that the equivalent width ( w) of the Fe-line feature increases exponentially with temperature up to 30 MK and then increases very slowly up to 40 MK. It remains between 3.5 and 4 keV in the temperature range of 30 – 45 MK. We compare our measurements of w with calculations made earlier by various investigators and propose that these measurements may improve theoretical models. We interpret the variation of both E p and w with temperature as being to the changes in the ionization and recombination conditions in the plasma during the flare, and as a consequence, the contribution from different ionic emission lines also varies. [ABSTRACT FROM AUTHOR]

Abstract: A nanocomposite electrolyte comprising a polymer–salt complex (PEO25–NaClO4) and an organically modified sodium montmorillonite (Na-MMT) has been prepared using tape casting technique. The effect of clay concentration on structural, microstructural and electrical properties has been investigated. X-ray diffraction (XRD) analysis confirmed the formation and structure of the nanocomposite. FTIR analysis suggested a clear evidence of polymer–ion–clay interaction indicated by the changes appearing in the ν(ClO4 −) and ν(C–O–C) bands as a function of the clay concentration. The surface properties and microstructure has been studied using atomic force microscopy (AFM) technique. Complex impedance spectrum (CIS) shows the existence of bulk and grain boundary effects in the nanocomposite films. The temperature dependence of electrical conductivity obeys VTF pattern of variation. [Copyright &y& Elsevier]

Realistic predictions of dynamic soil–structure interaction problems require appropriate constitutive models for the characterization of soils and interfaces. This paper presents a unified model based on the disturbed state concept (DSC). The parameters for the models for the Nevada sand, and sand–metal interface are obtained based on available triaxial test data on the sand and interfaces. The predicted stress–strain–pore water pressure behavior for the sand using the DSC model is compared with the test data. In addition, a finite element procedure with the DSC model, based on the generalized Biot’s theory, is used to predict the measured responses for a pile (aluminum) sand foundation problem obtained by using the centrifuge test. The predictions compared very well with measured pore water pressures. The DSC model is used to identify microstructural instability leading to liquefaction. A procedure is proposed to apply the proposed method for analysis and design for dynamic response and liquefaction. [ABSTRACT FROM AUTHOR]

The status of insulation in power equipment at any given point in time can be assessed by monitoring properties which are sensitive to the amount of aging. This procedure, called the diagnostic or non-destructive testing, has been in vogue for some time now. The diagnosis, as the name suggests, enables one to disseminate the condition of the insulation by making terminal or enclosure-centric measurements and as applied to transformers, a minimally invasive test procedure involving the examination of the oil phase, for arriving at information on the degradation of the cellulose insulation on the winding is indicated. An examination of the tracks provided by the by-products of chemical dissociation of cellulose, in solution with oil is recognized as a possible approach to condition monitoring. To this end, carefully controlled laboratory aging experiments have been performed on eight, nominally identical and scaled-down (pro-rated) models of single phase transformer units, incorporating all the essential features of actual power transformers under normal operating electric stress and accelerated thermal stress. Acquisition, analysis and validation of experimental data including dissolved gas analysis (DGA), examination of oil phase for the presence of Furans, measurement of the degree of polymerization (DP) of the paper insulation, electrical and certain chemical tests have all been performed to evolve an experimental data-base for assessing condition of insulation. [ABSTRACT FROM AUTHOR]

Microstructure characterization and phase transformation kinetics of a high-energy ball-milled and post-annealed stoichiometric (1:1 mol%) m-ZrO2 and amorphous ( a-) SiO2 powder mixture have been investigated by Rietveld analysis of X-ray powder diffraction data. The experimental results reveal that the ball-milling of stoichiometric powder results in the formation of c-ZrO2/ t-PSZ phases only. The ZrSiO4 phase was not found to form even after 30 h of milling. However, an almost stoichiometric ZrSiO4 (commercially known as zircon) phase is found to form even when a sample that was ball-milled for 5 min was post-annealed at 1473 K for 1 h. It appears that the intermediate t-PSZ phase plays an important role in zircon phase formation. The content of ZrSiO4 phase increases very sharply within 15 min of milling and remains almost unchanged after 30 h of ball-milling. It is also found that nanocrystalline zircon particles are almost free from lattice strain. Contamination by an α-Fe2O3 phase from the milling media results in a colour gradient (white to reddish) in the nanocrystalline ZrSiO4 phase. [ABSTRACT FROM AUTHOR]

A constitutive model based on the disturbed state concept (DSC) is proposed for stress-deformation and liquefaction response of interfaces in dynamic soil-structure interaction problems. The model parameters are determined by using comprehensive test data for Ottawa sand-concrete (medium roughness) interfaces by using the cyclic multidegree of freedom device. The model is validated by comparing the finite element predictions with the test data used for the determination of parameters and independent test not used for findings the parameters. A procedure based on the critical disturbance for the identification of liquefaction in the interfaces is proposed. It is found that the liquefaction in the interface can occur earlier than that in the surrounding sand. The DSC model can provide a realistic characterization of the interface behavior and can be used in analysis and design of dynamic soil-structure interaction problems. [ABSTRACT FROM AUTHOR]

Contamination and penetration of salmonellae into hatching eggs may comprise an important link in the transmission of these bacteria to growing birds, processed carcasses, and eventually to the consumer. In this study, a predictive model for Salmonella typhimurium as a function of initial cell number and storage or incubation time at a nearly constant temperature and humidity was developed and evaluated to compute the bacterial load after 1 d (holding), 10 d (candling), 17 d (incubation), and 21 d (chick processing). Experiments were conducted for S. typhimurium with both high initial bacterial load (HIBL) and low initial bacterial load (LIBL) of 6.0 and 3.5 log cfu/egg, respectively. Eggs with HIBL experienced 2.0 log reduction in the bacterial load after holding at 4°C for 24 h and 3.0 log increase in the bacterial load during incubation and hatch at approximately 37°C between 17 d and 21 d. Experimental data showed that bacterial load of S. typhimurium from holding to chick processing changed from 3.7 to 6.6 log cfu/egg and from 3.7 to 2.7 log cfu/egg in HIBL and LIBL eggs, respectively. The developed model was able to predict bacterial load of S. typhimurium from 3.6 to 6.6 log cfu/egg in HIBL eggs and from 3.4 to 2.7 log cfu/egg in LIBL eggs from holding to chick processing. Root mean square errors and plot of predicted compared with observed bacterial load of S. typhimurium in contaminated eggs yielded a good fit and prediction. The predicted and experimental results indicated that incubated broiler eggs have an increase in internal bacterial loads between incubation and hatch. This model can be used as a tool to predict bacterial load of S. typhimurium in contaminated eggs as well as help predict the behavior of S. typhimurium during hatch. [ABSTRACT FROM AUTHOR]

A ceramic oxide (NaDyTiO4), having layered perovskite structure, has been prepared by a standard high-temperature solid-state reaction technique. X-ray diffraction (XRD) studies have confirmed material formation under reported condition along with the presence of impurity (Na2Dy2Ti3O10) as the minor phase. Complex impedance spectroscopy (CIS) analysis has been carried out to investigate its microstructure and electrical properties as a function of frequency and temperature. CIS analysis has indicated that the electrical behavior of the material sample shows negative temperature coefficient of resistance (NTCR) typical to a semiconductor. Impedance studies have also indicated the presence of temperature dependent relaxation process in the material with a spread of relaxation time. The d.c. conductivity of the material as evaluated from the impedance spectrum has been observed to be ∼10−9 Scm−1 at room temperature (RT). It has been observed to increase as a function of temperature with a maximum of ∼10−5 Scm−1 at 550∘C. The conductivity variation shows a cross over from Mott-type hopping phenomena at lower temperatures to a thermally activated Arrhenius type behavior at high temperature. [ABSTRACT FROM AUTHOR]

A novel design methodology for test pattern generation in built-in self-test (BIST) is proposed. Experimental results are presented to demonstrate how a fault in the test pattern generator (TPG) itself can have serious consequences, a problem that has not been investigated. A solution is presented here, where the faults and errors in the generator itself are detected during the test in the TPG itself. This provides several major advantages, including the ability to distinguish between TPG and circuit under test (CUT) faults. In addition, this will ensure that there is no loss of fault coverage for the CUT caused by a fault in the TPG. Two different design methodologies are presented: The first guarantees all single fault/error detection, the second capable of detecting multiple faults and errors. The proposed linear feedback shift registers (LFSRs) do not have additional hardware overhead. Importantly, the test patterns generated have the potential to achieve superior fault coverage for both stuck-at and transition faults. [ABSTRACT FROM AUTHOR]

Frequency is an important parameter in power system monitoring, control, and protection. A least mean square (LMS) algorithm in complex form is presented in this paper to estimate power system frequency where the formulated structure is very simple. The three-phase voltages are converted to a complex form for processing by the proposed algorithm. To enhance the convergence characteristic of the complex form of the LMS algorithm, a variable adaptation step-size is incorporated. The performance of the new algorithm is studied through simulations at different situations of the power system. [ABSTRACT FROM AUTHOR]

The microwave dielectric CaZrO3 has been prepared in nanocrystalline form by high-energy ball milling an equimolar powder mixture of CaO and monoclinic (m) ZrO2. The formation of CaZrO3 is noticed in the X-ray diffraction pattern of 2 h ball-milled powder. At the early stage of milling, up to 4 h, the weight fraction of CaZrO3 increases rapidly and then slowly reaches almost the saturation value of ∼73 wt% within 18 h of milling. It is observed that in the course of milling, the weight fraction of c-ZrO3 increases continuously from its starting value, ∼2.5 wt%, to ∼43 wt% within 2 h of milling, and then reduces slowly to its starting value. It seems that the c-ZrO3 phase has been stabilized by CaO and takes part in the formation of CaZrO3 by mechanochemical reaction of nanocrystalline CaO and c-ZrO3 crystallites. However, post-annealing of 2, 6 and 18 h ball-milled samples results in the formation of ∼95 wt% CaZrO3 phase. The formation mechanism, phase transition kinetics, structure and microstructure changes in terms of lattice imperfections and relative phase abundances of individual phases have been estimated from the analysis of X-ray powder diffraction data of unmilled, ball-milled and post-annealed samples by Rietveld powder structure refinement. [ABSTRACT FROM AUTHOR]

Abstract: A layered perovskite ceramic oxide, NaNdTiO4, has been prepared by a standard solid-state reaction technique. Compound formation and phase identification has been confirmed by X-ray diffraction (XRD) studies. The material has been found to contain NaNdTiO4 as the predominant phase together with a minor impurity phase of Na2Nd2Ti3O10. Sample microstructure, observed through scanning electron microscopy, appears to be polycrystalline with shape anisotropy. Complex impedance analysis of the sample has indicated (i) the presence of grain boundary effects at temperatures above 200°C; (ii) negative temperature coefficient of resistance (NTCR) effect; and (iii) evidence of multiple electrical relaxation phenomena in the sample. The sample impedance behavior has been explained in terms of brick-layer model. The impedance measurements have shown the evidence of grain boundary conduction and lowering of barrier to the motion of charge carriers with rise in temperature. Electrical conductivity (σ dc) as evaluated from complex impedance spectrum, shows a large jump in the value at higher temperatures (∼1.66 × 10−4 Scm−1 at 550°C) when compared to the room temperature conductivity value (∼4.5 × 10−9 Scm−1). It has been attributed to the weakening of the interaction between the interlayer sodium ion and the perovskite layer. The results of ac conductivity as a function of frequency are also discussed. [Copyright &y& Elsevier]

A new plasticized composite polymer electrolyte (PCPE) based on poly(ethylene oxide)–NaClO4 dispersed with a ceramic filler (SnO2) and plasticized with polyethylene glycol (PEG200) is reported. The effect of plasticizer concentration on changes in structure/microstructure and their correlation with physical properties has been investigated and reported. A substantial enhancement in the electrical conductivity, by two orders of magnitude at room temperature, of the PCPE has been noticed when compared with that of composite polymer electrolyte (CPE) films without any plasticizer. This enhancement in electrical conductivity of the PCPE films agrees well with the changes in the local microstructure/structure on plasticizer addition. Grain boundary resistance (Rgb) and glass transition temperature (Tg) have been observed to decrease with increasing concentration of PEG200. Plasticizer addition has resulted in the suppression of crystallinity as observed from differential scanning calorimetry (DSC) and X-ray diffraction (XRD) studies. The DSC results indicate enhancement in the volume fraction of the amorphous phase, which appears to be consistent with the broadening in the polymer host peaks observed in X-ray diffractograms. The improvement in electrical conductivity has been achieved without any sharp deterioration in the thermal, electrochemical or mechanical stability of the PCPE thin films. These observations have been interpreted in terms of the action of plasticizer as a diluent/co-solvent. [Copyright &y& Elsevier]

Magnetoelectric (ME) materials with ferroelectric and magnetic transition temperatures near room temperature are of current interest in research due to their technological importance and potential applications. Herein, we report the coupled magnetic ordering and phonons in gallium ferrite (GaFeO3), a near room temperature ME perovskite, using magnetization and inelastic light scattering measurements as a function of temperature. Temperature-dependent magnetization behavior studied in a wide temperature range of 5–395 K at both field-cooled (FC) and zero-field-cooled (ZFC) conditions using different static magnetic fields confirms the magnetic transition temperature Tc at 220 K. On temperature dependent Raman spectroscopy, no significant changes in Raman spectra were observed at an elevated temperature that can be attributed to the absence of structural phase transition. Instead of expected anharmonic behavior, several librational (rigid rotation) and stretching modes of rigid BO6 units were found to be hardening below Tc, suggesting the significant magnetoelastic coupling contributions to phonon frequencies. The asymmetric stretching mode at 753 cm−1 is found to have larger spin-phonon coupling contribution (λ∼2.93), while the lattice mode at 153 cm−1 and external librational mode at 240 cm−1 had the lowest effect (λ∼0.88). [ABSTRACT FROM AUTHOR]

Time-dependent numerical simulations of the Kα complex of Fe xxvare carried out as a function of temperature–density–radiation field variations in high-temperature astrophysical and laboratory plasmas. In addition to several well-known features, the transient and steady-state spectra reveal the effects due to (a) time-dependent thermal and non-thermal radiation fields, (b) photo- and collisional excitation and ionization, and (c) high densities, on the‘quartet’ of principallines, and dielectronic satellites. The highly detailed models show precisely how, assuming a temporal–temperature correlation, the X-ray intensity varies between 6.6 and 6.7 keV and undergoes a‘spectral inversion’ in thewandzline intensities, characterizing an ionization- or a recombination-dominated plasma. The dielectronic satellite intensities are the most temperature-dependent features, but insensitive to density variations, and significantly contribute to the Kα complex forleading to asymmetric profiles. The 6.7-keV Kα complex should be a potential diagnostic of X-ray flares in active galactic nuclei, afterglows in gamma-ray bursts, and other non-equilibrium sources with the high-resolution measurements possible from the upcoming missionAstro-E2. It is also shown that high electron densities attenuate the line intensities in simulations relevant to laboratory plasmas, such as in inertial confinement fusion, laser, or magnetic Z-pinch devices. [ABSTRACT FROM AUTHOR]

The degradation of electrical insulation in transformers is traced to thermoelectric processes. Existence of localized hot regions due to thermal insulating properties of electrical insulation would cause thermal runaway around these regions. In an earlier paper [1], the authors presented analytical methods for estimating the temperature and its distribution at different points of the transformer based on a closed-form mathematical technique using a generalized heat conduction (GHC) model. Certain aspects of the inhomogeniety of the several components of the winding and incorporation of distributed heat source were not addressed. Also, a rigorous treatment involving the changes in winding resistance, which was built into the thermal model as an empirical correction factor, has now been modified and incorporated in the GHC. These considerations have now improved the accuracy of estimation of hottest spot temperature. [ABSTRACT FROM AUTHOR]

A unified scheme using the R-matrix method has been developed for electron–ion recombination subsuming heretofore separate treatments of radiative and dielectronic recombination (RR and DR). The ab initio approach within the coupled channel approximation has several inherent advantages in addition to the natural unification of resonant and non-resonant phenomena. It enables a general and self-consistent treatment of photoionization and electron–ion recombination employing identical wavefunction expansion. Detailed balance takes account of interference effects due to resonances in cross sections, calculated explicitly for a large number of recombined (e+ion) bound levels over extended energy regions. The theory of DR by Bell and Seaton is adapted for high-n resonances in the region below series limits. The R-matrix method is employed for (A) partial and total photoionization and photorecombination cross sections of (e+ion) bound levels, and (B) DR and (e+ion) scattering cross sections. Relativistic effects and fine structure are considered in the Breit–Pauli approximation. Effects such as radiation damping may be taken into account where necessary. Unified recombination cross sections are in excellent agreement with measurements on ion storage rings to about 10–20%. In addition to high accuracy, the strengths of the method are: (I) both total and level-specific cross sections and rate coefficients are obtained, and (II) a single (e+ion) recombination rate coefficient for any given atom or ion is obtained over the entire temperature range of practical importance in laboratory and astrophysical plasmas, (III) self-consistent results are obtained for the inverse processes of photoionization and recombination; comprehensive datasets have been computed for over 50 atoms and ions. Selected data are presented for iron ions. [Copyright &y& Elsevier]

To date, all of the proposals for low-power designs of RAMs essentially focus on circuit-level solutions. What we propose here is a novel architecture (high) level solution. Our methodology provides a systematic tradeoff between power and area. Also, it allows tradeoff between test time and power consumed in test mode. Significantly, too, the proposed design has the potential to achieve performance improvements white simultaneously reducing power. In this respect, it stands apart from other approaches where power reduction results in speed reduction. The basic approach here divides the RAM into modules, interconnecting these modules in a binary tree where the tree can be reconfigured dynamically during normal operation and during test mode. Furthermore, during test mode, most of the RAM can be switched off, which provides major power reduction, while test-application time is reduced. The aspect ratio of the modules is allowed to vary as a design parameter. The chosen aspect ratio for module impacts power/access time/area tradeoffs. Such novel features make the proposed methodology of potential practical significance. Also, a design tool is developed which inputs various parameters, such as desired power/performance, giving outputs basic design parameters, such as the needed number of modules, area overhead, and resulting test speed-up. [ABSTRACT FROM AUTHOR]

A novel polymer matrix composite using coconut shell powder (CSP) as a filler material has been processed by a powder metallurgy technique. A mixture of ultrahigh molecular weight polyethylene (UHMWPE) powder and CSP was compacted at 200 °C in a die-punch arrangement. The composite material remained tough when the CSP content was 20–30 vol.%, as revealed by notch impact tests and fractography studies. However, the compressive strength of the UHMWPE–CSP composite decreased rapidly beyond 20 vol.% CSP. In this paper, preliminary results are presented to throw light on mechanical properties and on some aspects of the processing method used. [Copyright &y& Elsevier]

Summary Background. This prospective study, conducted in patients with Chiari I malformation (C I) related syringomyelia who underwent posterior decompression and duroplasty, utilizes radionuclide cisternography in order to study the cerebrospinal fluid (CSF) dynamics at the foramen magnum and to predict the clinical outcome following surgery. Methods. 17 consecutive patients of C I with syringomyelia (but without hydrocephalus or fixed atlanto-axial dislocation), underwent a detailed neurological examination and were assigned a clinical disability score based on the modified Klekamp and Samii score. A radionuclide cisternography (using Tc99m-DTPA) was performed via the lumbar route and the ascent of the tracer was followed utilizing a gamma camera immediately after injection and then sequentially after 1, 2, 4, 6 and 24 hours. After posterior decompression and duroplasty, the modified Klekamp and Samii score was repeated at follow-up visits (range: 3 months to one year) along with radionuclide cisternography at 3 months, and MR imaging at 6 months. Findings. Three patterns of tracer flow were observed: a) rapid flow (n=7); b) supratentorial subarachnoid delay (n=7); and, c) foramen magnum block (n=3). The patients having foramen magnum block had the poorest clinical scores on admission. At follow up, there was an improvement in the clinical scores so that the mean scores in all three categories reached nearly the same level. Following posterior decompression, the radionuclide cisternography performed in 10 patients showed a rapid flow of the tracer without any obstruction. The syrinx resolved in 4 of the 11 patients in whom an MRI was done. Interpretation. The patients with C I with syringomyelia may often have a free flow of tracer across the FM. Posterior decompression and duroplasty provides maximum clinical relief in patients with a demonstrable foramen magnum block on radionuclide cisternography while those with a normal flow have less relief. The symptomatology related to brain-stem compression immediately responds to the surgical procedure but the syrinx-induced signs and symptoms of spinal cord dysfunction persist. [ABSTRACT FROM AUTHOR]

A new design methodology for a pattern generator is proposed, formulated in the context of on-chip BIST. The design methodology is circuit-specific and uses synthesis techniques to design BIST generators. The pattern generator consists of two components: a pseudorandom pattern generator (like an LFSR or, preferably, a GLFSR) and a combinational logicto map the outputs of the pseudorandom pattern generator. This combinational logic is synthesized to produce a given set of target patterns by mapping the outputs of the pseudorandom pattern generator. It is shown that, for a particular CUT, an area-efficient combinational logic block can be designed/synthesized to achieve 100 (or almost 100) percent single stuck-at fault coverage using a small number of test patterns. This method is significantly different from weighted pattern generation and can guarantee testing of all hard-to-detect faults without expensive test point insertion. Experimental results on common benchmark netlists demonstrate that the fault coverage of the proposed pattern generator is significantly higher compared to conventional pattern generation techniques. The design technique for the logic mapper is unique and can be used effectively to improve existing pattern generators for combinational logic and scan-based BIST structures. [ABSTRACT FROM AUTHOR]

The growth of TiO2 nanorods on a WC–Co substrate by metalorganic chemical vapor deposition has been observed by SEM and TEM. The nanorods diameter and length were about 50–100 nm and 0.5–2 μm, respectively. Nanorod growth was observed at 500°C, while mostly particles were deposited at 600°C and a thin coating was formed at 400°C. It appears that the presence of cobalt catalyzes the directional growth of TiO2 and NH3 enhances this growth behavior. In the presence of NH3, thinner and longer nanorod growth was observed. [Copyright &y& Elsevier]

ABSTRACT The Kα resonance complexes in oxygen ions O i–O viare theoretically computed, and resonance oscillator strengths and wavelengths are presented. The highly resolved photoionization cross-sections, with relativistic fine structure, are computed in the coupled channel approximation using the Breit–Pauli R-matrix method. A number of strong Kα resonances are found to be appreciable, with resonance oscillator strengths f[sub r] > 0.1 . The Kα resonance wavelengths of O i–O vilie in the relatively narrow wavelength range 22–23.5 Å, and the X-ray opacity in this region should therefore be significantly affected by K → L transitions in oxygen. The results should be useful in the interpretation of soft X-ray spectra observed from Chandra and XMM–Newton. [ABSTRACT FROM AUTHOR]

The growth and morphological features of MOCVD TiOxNy films have been characterized to evaluate the effect of various process parameters on film growth. XRD analysis of the films deposited at 600°C on Si(1 1 1) and mica show a TiN(1 1 1) peak at 2θ=36.6°, but only anatase peaks are detected below 550°C. Above 650°C, both anatase and rutile peaks are detected. The presence of ammonia is not effective below 550°C as the deposited film is mostly TiO2. Also, ammonia does not play any role in homogeneous nucleation in the gas phase, as evident by the deposition of anatase/rutile particles above 650°C. The following changes in the morphological features are observed by varying process parameters. By increasing the ratio of titanium-isopropoxide to ammonia flow, the cluster shape changes from angular to rounded; dilution of the flow results in larger elongated clusters; increase in flow rate at constant precursor to ammonia ratios, changes the cluster shape from rounded to elongated and the cluster size deceases. Deposition at higher temperatures results in finer clusters with a slower growth rate and eventually results in a very thin film with particle deposition at 650°C and above. [Copyright &y& Elsevier]

Thermoelectric properties of single wall carbon nanotubes (SWNT) are quite sensitive to gases in contact with the tube walls. This effect makes possible a thermoelectric chemical sensor. Large, reversible swings in thermoelectric power (S), sometimes even involving sign changes in S, have been observed. Even contact of the SWNTs with He and N 2 and H 2 result in easily detectable and reversible changes in S. Smaller, polar alcohol molecules stimulate a large thermoelectric response, although H 2 O has no effect. For adsorption of six membered ring molecules C 6 H n in SWNTs, the large thermoelectric response observed for Benzene (n=6) is seen to decrease as the π electrons in the molecule are removed, and the coupling between the molecules and the SWNT is thereby reduced. These effects are discussed in terms of the diffusion thermopower for a rope, and a new scattering channel associated with adsorbed molecules. [ABSTRACT FROM PUBLISHER]

This article presents a new approach for the estimation of power system frequency for power quality studies using bus voltage signals corrupted with noise and harmonics. The method involves application of a nonlinear filtering technique like a Kalman filter in the complex domain known as extended complex Kalman filter (ECKF). This article systematically outlines the development of the complex Kalman filter model using one phase measurement in the state space form and relevant equations to compute the Kalman gain. The nonlinear filter is then applied to several static and dynamic conditions of the power system and the frequency is estimated. Presence of harmonics and noise in bus voltage signal is taken into consideration in evaluating the performance of this new filter in terms of rejecting noise and harmonics. In the presence of decaying dc components in the signal, the new filter is found to be very effective as validated from the digital simulation tests. Further the ECKF is applied for the frequency estimation of an ac-dc system during load and line reactance changes and the estimation results reveal high accuracy and convergence. In general, it is observed that the proposed filter outperforms in terms of accuracy and speed of convergence the reported real extended Kalman filter during sudden transient changes. [ABSTRACT FROM AUTHOR]

Electrical transport (resistance R and thermoelectric power S), Raman scattering, and hydrogen adsorption are used to study the interaction of hydrogen molecules with ropes of single-walled carbon nanotubes. The data are consistent with H2 physisorption under the experimental conditions investigated (4 K<T<500 K; 0.1 atm<P<20 atm). The response of S, R to 1 atm hydrogen at 500 K is consistent with the introduction of a new scattering channel for electrons/holes in the metallic tubes. Raman scattering from the Q-branch of hydrogen molecules adsorbed on the surface is found shifted only by 1–2 cm−1 from their frequencies in the free molecule and indicates that two different adsorption sites can be detected. Finally, H2 wt% storage in heavily processed ropes of SWNTs are found to exceed 6% at ∼1 atm and T=77 K and the isosteric heat of adsorption is found to be 120 meV. [Copyright &y& Elsevier]

Thermoelectric properties of single wall carbon nanotubes (SWNT) are quite sensitive to gases in contact with the tube walls. This effect makes possible a thermoelectric chemical sensor. Large, reversible swings in thermoelectric power (S), sometimes even involving sign changes in S, have been observed. Even contact of the SWNTs with He and N 2 and H 2 result in easily detectable and reversible changes in S. Smaller, polar alcohol molecules stimulate a large thermoelectric response, although H 2 O has no effect. For adsorption of six membered ring molecules C 6 H n in SWNTs, the large thermoelectric response observed for Benzene (n=6) is seen to decrease as the π electrons in the molecule are removed, and the coupling between the molecules and the SWNT is thereby reduced. These effects are discussed in terms of the diffusion thermopower for a rope, and a new scattering channel associated with adsorbed molecules. [ABSTRACT FROM AUTHOR]

A new method for determining ultra-trace levels of hexavalent chromium in ambient air has been developed. The method involves a 24-h sampling of air into potassium hydroxide solution, followed by silica gel column separation of chromium (VI), then preconcentration by complexation and solvent extraction. The chromium (VI) complex was dissolved in nitric acid. The resultant chromium ions were determined by inductively coupled plasma mass spectrometry (ICP–MS) using a dynamic reaction cell (DRC) with ammonia as the reactive gas to reduce polyatomic interferences. The interconversion of chromium in potassium hydroxide solution and air sample matrix were investigated under ambient conditions. It was found that there was no conversion of chromium (VI) into chromium (III) species. However, it was observed that some chromium (III) species were converted into chromium (VI) species. For a KOH solution containing 100 μg l−1 of chromium (III) species, the rate of conversion was found to be 3% after 24 h exposure, 8% after 48 h, 10% after 72 h and no further conversion was observed thereafter. However, in a solution containing air sample matrix, 9.3% of chromium (III) converted to chromium (VI) within 6 h, and during the course of a 11-day exposure period, 13% (range 8–17%) of chromium (III) converted to chromium (VI). The method detection limit (MDL) for chromium (VI) in potassium hydroxide solution (0.025 M) was found to be 2×10−2 μg l−1. This is equivalent to 0.2 ng m−3 (for 23 m3 air sampled into 200 ml of KOH solution over a 24-h period). The recovery of spiked chromium (VI) from solutions containing air sample matrix was 95±9% (n=8). Matrix related interferences were estimated to be less than 10% based on recovery studies. The concentration of airborne chromium (VI) in Sydney residential areas was found to be less than 0.2 ng m−3, however, in industrial areas the concentrations ranged from 0.2 to 1.3 ng m−3 using this analytical procedure. [Copyright &y& Elsevier]