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We fabricated an anthracene thin-film transistor (TFT) with an ultrathin layer (∼450 nm) of poly-vinylidene fluoride (PVDF)/graphite oxide nanoplatelets (GOnP) nanocomposite as a gate insulator. We obtained a TFT device with excellent electrical characteristics at low operating voltages (<1 V). The dielectric is a high- ε gate insulator with a static dielectric constant of εr = 15.6. This device was found to have a field effect mobility of 1.1 cm2 V−1 s, a threshold voltage of 0.34 V, an exceptionally low subthreshold slope (SS) of 380 mV decade−1 and an on/off ratio of 105. The combination of favorable properties opens up the possibility to utilize such TFTs effectively at voltages as low as below 1 V. Such high- ε PVDF/GOnP gate dielectric appears to be highly promising candidates for organic nonvolatile memories and sensor field effect transistors (FETs). [ABSTRACT FROM AUTHOR]

Quantitative analysis of microstructures using computerized stereology systems is an essential tool in many disciplines of bioscience research. Section thickness determination in current nonautomated approaches requires manual location of upper and lower surfaces of tissue sections. In contrast to conventional autofocus functions that locate the optimally focused optical plane using the global maximum on a focus curve, this study identified by two sharp 'knees' on the focus curve as the transition from unfocused to focused optical planes. Analysis of 14 grey-scale focus functions showed, the thresholded absolute gradient function, was best for finding detectable bends that closely correspond to the bounding optical planes at the upper and lower tissue surfaces. Modifications to this function generated four novel functions that outperformed the original. The 'modified absolute gradient count' function outperformed all others with an average error of 0.56 μm on a test set of images similar to the training set; and, an average error of 0.39 μm on a test set comprised of images captured from a different case, that is, different staining methods on a different brain region from a different subject rat. We describe a novel algorithm that allows for automatic section thickness determination based on just out-of-focus planes, a prerequisite for fully automatic computerized stereology. [ABSTRACT FROM AUTHOR]

The present work deals with recognition of handwritten characters of Bangla, a major script of the Indian sub-continent. The main contributions presented here are (a) generation of a database of handwritten basic characters of Bangla and (b) development of a handwritten character recognition scheme suitable for scripts like Bangla consisting of many similar shaped characters for the benchmark results. The present database is a pioneering development in the context of recognition of off-line handwritten characters of this script. It has 37,858 handwritten samples and accommodates a large spectrum of handwriting style by Bangla speaking population. This database will be made available () free of cost to researchers for further studies. Also, we identified two major factors affecting high recognition accuracies for the present character samples, namely, (a) erratic nature of the presence of headline (shapes of Bangla characters usually contain a horizontal line in its upper part) and (b) existence of several pairs of similar shaped characters. The proposed recognition approach takes care of the above factors. It identifies any confusion in the first stage classification between a pair of similar shaped character classes and resolves the same in the second stage classification by extracting a feature vector based on a non-uniform grid. [ABSTRACT FROM AUTHOR]

Global changes are already having an impact on South Indian farmers. Climate change is affecting the agricultural sector since it is dependent on climatic conditions and water resource availability. The impacts tend to be greater in semi-arid hard rock areas with few water resources. Furthermore, South India area is experiencing a profound agrarian crisis, which is linked, among others, to debt and credit problems. The study reported in this paper aims to develop a methodology to compare and rank farmers according to their ability to adapt to global change. The definition of adaptive capacity is based on a livelihood assets approach. Indicators are evaluated through individual surveys among farmers, then, weighted using the analytic hierarchy process and aggregated via compromise programming. The result is a standardized score measuring the distance of each farmer from an ideal adaptive capacity. Farmers are ranked according to this distance, which allows a comparison of their relative ability to adapt. At the basin scale, it shows that the geographic position of farmers is a significant factor in adaptation performance. The proximity of an administrative center contributes to an increase of their adaptive capacity. Small farming areas limit the adaptive capacities of marginal and small farmers while the largest farmers are constrained by economic factors such as large loans. These study findings offer interesting indications on the variability of farmers' weaknesses and are bringing a better understanding of the causes of poor performance. [ABSTRACT FROM AUTHOR]

A novel two-phase polymer nanocomposite film comprising of polyvinylidene fluoride (PVDF) and nanocrystalline (∼90 nm) semiconducting multiferroic BiFeO3 (BFO) have been fabricated by hot-molding technique. Such flexible thick nanocomposite films, semicrystalline in nature, exhibited extraordinarily high effective dielectric permittivity εeff ∼ 103 (compared with that of pure PVDF) near the low percolation threshold ( fc = 0.12) at room temperature (RT) and the films also possessed low dielectric loss (∼0.18). The polarization-electric field ( P-E) hysteresis loops are displayed at RT, which indicate ferroelectric like behavior of PVDF still persists in the percolative nanocomposite. There is also large increase of remanent polarization of BFO in the composite indicating improvement of the multiferroic behavior of BFO embedded in the PVDF polymer. The sample also indicates good fatigue endurance. Formation of microcapacitors and percolative behavior are correlated to explain the obtained results based on the special geometry of the BFO nanofillers. © 2012 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys, 2012 [ABSTRACT FROM AUTHOR]

Summary A substantial proportion of the streptococcal species found in dental plaque biofilms are able to interact with the abundant salivary enzyme α-amylase. These streptococci produce proteins that specifically bind amylase. An important plaque species, Streptococcus mitis, secretes a 36-kDa amylase-binding protein into the extracellular milieu. Proteins precipitated from S. mitis NS51 cell culture supernatant by the addition of purified salivary amylase were separated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis, transferred to a membrane, and a prominent 36-kDa band was cut from the membrane and sequenced to yield the N-terminal amino acid sequence DSQAQYSNGV. Searching the S. mitis genome sequence database revealed a single open reading frame containing this sequence, and the gene was amplified by the S. mitis genomic DNA polymerase chain reaction. The coding region of this open reading frame, designated amylase-binding protein C (AbpC), was cloned into an Escherichia coli expression vector and the recombinant AbpC (rAbpC) was purified from the soluble fraction of the E. coli cell lysate. Purified AbpC was found to interact with immobilized amylase, confirming AbpC as a new streptococcal amylase-binding protein. [ABSTRACT FROM AUTHOR]

In various organisms, an array of enzymes is involved in the synthesis and breakdown of methylglyoxal. Through these enzymes, it is intimately linked to several other physiologically important metabolites, suggesting that methylglyoxal has some important role to play in the host organism. Several in vitro and in vivo studies showed that methylglyoxal acts specifically against different types of malignant cells. These studies culminated in a recent investigation to evaluate a methylglyoxal-based formulation in treating a small group of cancer patients, and the results were promising. Methylglyoxal acts against a number of pathogenic microorganisms. However, recent literature abounds with the toxic effects of methylglyoxal, which are supposed to be mediated through methylglyoxal-derived advanced glycation end products (AGE). Many diseases such as diabetes, cataract formation, hypertension, and uremia are proposed to be intimately linked with methylglyoxal-derived AGE. However methylglyoxal-derived AGE formation and subsequent pathogenesis might be a very minor event because AGE are nonspecific reaction products that are derived through the reactions of carbonyl groups of reducing sugars with amino groups present in the side chains of lysine and arginine and in terminal amino groups of proteins. Moreover, the results of some in vitro experiments with methylglyoxal under non-physiological conditions were extrapolated to the in vivo situation. Some experiments even showed contradictory results and were differently interpreted. For this reason conclusions about the potential beneficial effects of methylglyoxal have often been neglected, thus hindering the advancement of medical science and causing some confusion in fundamental understanding. Overall, the potential beneficial effects of methylglyoxal far outweigh its possible toxic role in vivo, and it should be utilized for the benefit of suffering humanity. [ABSTRACT FROM AUTHOR]

This paper primarily concerns the problem of isolated handwritten numeral recognition of major Indian scripts. The principal contributions presented here are 1) pioneering development of two databases for handwritten numerals of the two most popular Indian scripts, 2) a multistage cascaded recognition scheme using wavelet-based multiresolution representations and multilayer perceptron (MLP) classifiers, and 3) application of 2 for the recognition of mixed handwritten numerals of three Indian scriptsߝDevanagari, Bangla, and English. The present databases include, respectively, 22,556 and 23,392 handwritten isolated numeral samples of Devanagari and Bangla collected from real-life situations, and these can be made available free of cost to researchers of other academic institutions. In the proposed scheme, a numeral is subjected to three MLP classifiers corresponding to three coarse-to-fine resolution levels in a cascaded manner. If rejection occurs even at the highest resolution, another MLP is used as the final attempt to recognize the input numeral by combining the outputs of three classifiers of the previous stages. This scheme has been extended to the situation when the script of a document is not known a priori or the numerals written on a document belong to different scripts. Handwritten numerals in mixed scripts are frequently found in Indian postal mail and tabular form documents. [ABSTRACT FROM AUTHOR]

Twelve districts of the state of West Bengal, India are affected by arsenic (As) and millions of individuals are consuming As-contaminated groundwater. The probable adverse effects of As on pregnancy outcome (stillbirth and miscarriage) are yet to be properly studied. The present investigation is an attempt to understand the effects of AS exposure on the pregnancy outcome in Bengali women exposed to AS through drinking water and residing in different villages in North 24 Parganas District of West Bengal. The results show a significantly higher rate of stillbirths and miscarriages than those in the unexposed population. [ABSTRACT FROM AUTHOR]

The present study evaluates the mental health of participants 3 to 6 months after completing treatment at a shared mental health care clinic. Twenty-five participants completed the Patient Health Questionnaire (PHQ) and the World Health Organization Disability Assessment Scale version II (WHODAS-II) at entry, exit, and 3 to 6 months following treatment. Results for the PHQ found significant sustained improvement for major depression, other anxiety syndrome, and somatoform disorder. The WHODAS-II scale demonstrated that significant improvement was maintained 3 to 6 months following treatment completion. These findings suggest that patients receiving short-term therapy and psychiatric consultation in a shared care setting may show significant, sustained improvement in mental and physical functioning. [ABSTRACT FROM AUTHOR]

Application of the normalised ℋ∞ loop-shaping technique for design and simplification of damping controllers in the LMI framework is illustrated. A linearised model of the power system is pre- and post-compensated using the loop-shaping approach. The problem of robust stabilisation of a normalised coprime factor plant description is translated to a generalised ℋ∞ problem. The solution is sought numerically using LMIs with additional pole-placement constraints. This ensures that the time-domain specifications are met besides robust stabilisation. [ABSTRACT FROM AUTHOR]

In this paper a frequency plane analysis of both normal and diseased ECG signals is performed specifically for disease identification. Image processing techniques are used to develop an automated data acquisition package of 12 lead ECG signals from paper records. A regeneration domain is also developed to check the captured pattern with the original wave shape. A QRS complex detector with an accuracy level &nvsim;98.4% in up to 30% signal to noise level is developed. Discrete Fourier transform (DFT) is performed to obtain the frequency spectrum of every ECG signal. Some interesting amplitude and phase response properties of chest lead V2, V3, V4, V6 and limb lead I, II, III, AVL, AVF are seen. Both amplitude and phase properties are different for normal and diseased subjects and can serve an important role in disease identification. A statistical analysis of amplitude property is carried out to show that this property is significantly different for normal and diseased subjects. [ABSTRACT FROM AUTHOR]

This paper aims at automatic understanding of online handwritten mathematical expressions (MEs) written on an electronic tablet. The proposed technique involves two major stages: symbol recognition and structural analysis. Combination of two different classifiers have been used to achieve high accuracy for the recognition of symbols. Several online and of line features are used in the structural analysis phase to identify the spatial relationships among symbols. A context-free grammar has been designed to convert the input expressions into their corresponding IbX strings which are subsequently converted into MathML format. Contextual information has been used to correct several structure interpretation errors. A new method for evaluating performance of the proposed system has been formulated. Experiments on a dataset of considerable size strongly support the feasibility of the proposed system. [ABSTRACT FROM AUTHOR]

We report the dielectric relaxation behaviour in the antiferroelectric SmC A * and ferrielectric SmC γ * phases of the antiferroelectric liquid crystal 4-[5-(4-octloxyphenyl)-2-pyrimidinyl]phenyl 4,4,4-trifluoro-3-(methoxyphenyl)butanoate which shows an antiferroelectric transition at around 88±0.1°C. In the SmC A * phase, two dielectric relaxation modes have been found, namely the usual antiferroelectric Goldstone mode and another arising from molecular rotation around its short axis. In the SmC γ * phase, one dielectric relaxation mode has been observed due to the ferrielectric Goldstone mode. Dielectric increments and relaxation frequencies of the antiferroelectric and ferrielectric phases are estimated from the fits of the Cole-Cole function of the dielectric spectrum. The dependence of the bias field in the ferrielectric phase is also discussed. [ABSTRACT FROM AUTHOR]

Studies the transport and dielectric properties of V[sub2]O[sub5]-MnO-TeO[sub2] glasses containing two transition metal ions. Change in the conductivity on addition of MnO; Difference between behavior of Mn-free and Mn-added glasses; Variation in the imaginary part of the dielectric constant for different glasses at different frequencies.