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The study was aimed to modify sweet potato starches (SPS) of Indonesian varieties to be suitable for starch noodle production. SPS were isolated from four varieties, namely Sukuh, Cangkuang, Jago and Papua Salosa. The native SPS were adjusted to moisture content of 25% and exposed to heat moisture treatment (HMT) at 110°C for 3, 4 and 5 h. The native and treated starches were characterized for swelling power, solubility, gel hardness, pasting properties and microstructure. The results indicated that HMT reduced the swelling power and solubility, eventhough the length of treatment did not affect both properties. Except in Papua Salosa, HMT increased gel hardness with the longer treatment time resulted in less increase. HMT increased pasting temperature, and longer treatment time led to higher increased value. HMT reduced peak viscosity, and the longer treatment resulted in the higher reduction. The final viscosity of treated starches was higher than the native ones, except for Papua Salosa. The highest final viscosity with a significant increment was shown by Sukuh (517.5 RVU) treated for 4 h. Longer HMT led to a slightly decrease in final viscosity. In general, HMT clearly shifted SPS from Type A to Type C of amylographic patern, except for Papua Salosa. Photomicroscopy showed that the forms of SPS granules of all varieties were spheric. HMT did not modify the form and size of the starch granules. The greatest effect of HMT on the physicochemical changes was observed in SPS from Sukuh, followed by Jago and Cangkuang varieties. It could be concluded that heat moisture treated Sukuh starch for 3 h was recommended for noodle production. [ABSTRACT FROM AUTHOR]

Molecular markers linked to QTL contributing to agronomic and fibre quality traits would be useful for cotton improvement. We have attempted to tag yield and fibre quality traits with AFLP and SSR markers using F and F populations of a cross between two Gossypium hirsutum varieties, PS56-4 and RS2013. Out of 50 AFLP primer combinations and 177 SSR primer pairs tested, 32 AFLP and four SSR primers were chosen for genotyping F individuals. Marker-trait associations were studied for eight agronomic and five fibre quality traits through simple and multiple regression analysis (MRA) using a set of 92 AFLP polymorphic loci and four SSR markers. Simple linear regression analysis (SLRA) identified 23 markers for eight different traits whereas multiple regression analysis identified 30 markers for at least one of the 13 traits. SSR marker BNL 3502 was consistently identified to be associated with fibre strength. While all the markers identified in SLRA were also detected in MRA, as many as 16 of the 30 markers were identified to be associated with respective traits in both F and F generations. The markers explained up to 41 per cent of phenotypic variation for individual traits. A number of markers were found to be associated with multiple traits suggesting clustering of QTLs for fibre quality traits in cotton. [ABSTRACT FROM AUTHOR]

PurposeThe purpose of this study was to investigate the effect of cataract surgery and pupil dilation on iris pattern recognition for personal authentication.MethodsProspective non-comparative cohort study. Images of 15 subjects were captured before (enrolment), and 5, 10, and 15 min after instillation of mydriatics before routine cataract surgery. After cataract surgery, images were captured 2 weeks thereafter. Enrolled and test images (after pupillary dilation and after cataract surgery) were segmented to extract the iris. This was then unwrapped onto a rectangular format for normalization and a novel method using the Discrete Cosine Transform was applied to encode the image into binary bits. The numerical difference between two iris codes (Hamming distance, HD) was calculated. The HD between identification and enrolment codes was used as a score and was compared with a confidence threshold for specific equipment, giving a match or non-match result. The Correct Recognition Rate (CRR) and Equal Error Rates (EERs) were calculated to analyse overall system performance.ResultsAfter cataract surgery, perfect identification and verification was achieved, with zero false acceptance rate, zero false rejection rate, and zero EER. After pupillary dilation, non-elastic deformation occurs and a CRR of 86.67% and EER of 9.33% were obtained.ConclusionsConventional circle-based localization methods are inadequate. Matching reliability decreases considerably with increase in pupillary dilation. Cataract surgery has no effect on iris pattern recognition, whereas pupil dilation may be used to defeat an iris-based authentication system. [ABSTRACT FROM AUTHOR]

The resilience of identity verification systems to subsampling and compression of human iris images is investigated for three high-performance iris-matching algorithms. For evaluation, 2156 images from 308 irises from the extended Chinese Academy of Sciences Institute of Automation database were mapped into a rectangular format with 512 pixels circumferentially and 80 radially. For identity verification, the 48 rows that were closest to the pupil were taken and images were resized by subsampling their Fourier coefficients. Negligible degradation in verification is observed if at least 171 circumferential and 16 radial Fourier coefficients are preserved, which would correspond to sampling the polar image at 342 times 32 pixels. With JPEG2000 compression, improved matching performance is observed down to 0.3 b/pixel (bpp), attributed to noise reduction without a significant loss of texture. To ensure that the iris-matching algorithms studied are not degraded by image compression, it is recommended that normalized iris images should be exchanged at 512 times 80 pixel resolution, compressed by JPEG 2000 to 0.5 bpp. This achieves a smaller file size than the ANSI/INCITS 379-2004 iris image interchange format. [ABSTRACT FROM PUBLISHER]

Abstract: This article presents a novel method for mean filtering that reduces the required number of additions and eliminates the need for division altogether. The time reduction is achieved using basic store-and-fetch operations and is irrespective of the image or neighbourhood size. This method has been tested on a variety of greyscale images and neighbourhood sizes with promising results. These results indicate that the relative time requirement reduces with increase in image size. The method''s efficiency also improves significantly with increase in neighbourhood size thereby making it increasingly useful when dealing with large images. [Copyright &y& Elsevier]

The role played by dendritic cells (DCs) in Leishmania donovani infection is poorly understood. Here, we report that L. donovani amastigotes efficiently infect human peripheral-blood monocyte-derived DCs. Opsonization with normal human serum enhanced the infectivity of amastigotes and promastigotes only marginally. Surface attachment versus internalization was distinguished by incubation of DCs with live, fluorescein isothiocyanate-labeled parasites, followed by quenching with crystal violet. Infection with amastigotes was accompanied by DC maturation, as was evident from the up-regulation of maturation-associated cell-surface markers, the nuclear translocation of RelB, and the release of cytokines. Amastigote-primed DCs produced inflammatory cytokines in response to subsequent treatment with interferon-gamma or anti-CD40 monoclonal antibody. When cocultured, amastigote-infected DCs induced T helper cell type 1 (Th1) responses both in naive allogeneic CD4(+) T cells and in autologous CD4(+) T cells from patients with kala-azar and up-regulated the expression of T-bet. Our data reveal that infection with L. donovani amastigotes induces a Th1 cytokine milieu in both DCs and T cells. Copyright © 2006 Infectious Diseases Society of America [ABSTRACT FROM AUTHOR]

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The effects of microwave heating on antinutrients, raffinose family oligosaccharides, sucrose, in vitro protein digestibility and solubility of three selected varieties of whole common bean (Roba, Awash and Beshbesh) were evaluated. The increase in in vitro protein digestibility as a consequence of microwave heating depends on the time of heating. The best in vitro protein digestibility due to reduced antinutrients such as tannins, phytic acid and trypsin inhibitor activity was obtained with a 3-minute exposure. Protein solubility, tannins and trypsin inhibitor activity of treated whole bean samples decreased as microwave time increased. The results indicate that microwave heating can be used to effectively reduce some antinutrients and improve protein quality. [ABSTRACT FROM AUTHOR]

Resistance of chickpea against the disease caused by the ascomycete Ascochyta rabiei is encoded by two or three quantitative trait loci, QTL1, QTL2 and QTL 3. A total of 94 recombinant inbred lines developed from a wide cross between a resistant chickpea line and a susceptible accession of Cicer reticulatum, a close relative of cultivated chickpea, was used to identify markers closely linked to QTL1 by DNA amplification fingerprinting in combination with bulked segregant analysis. Of 312 random 10mer oligonucleotides, 3 produced five polymorphic bands between the parents and bulks. Two of them were transferred to the population on which the recent genetic map of chickpea is based, and mapped to linkage group 4. These markers, OPS06-1 and OPS03-1, were linked at LOD-scores above 5 to markers UBC733B and UBC181A flanking the major ascochyta resistance locus. OPS06-1 mapped at the peak of the QTL between markers UBC733B (distance 4.1 cM) and UBC181A (distance 9.6 cM), while OPS03-1 mapped 25.1 cM away from marker UBC733B on the other flank of the resistance locus. STMS markers localised on this linkage group were transferred to the population segregating for ascochyta resistance. Three of these markers were closely linked to QTL1. Twelve of 14 STMS markers could be used in both populations. The order of STMS markers was essentially similar in both populations, with differences in map distances between them. The availability of flanking STMS markers for the major resistance locus QTL1 will help to elucidate the complex resistance against different Ascochyta pathotypes in future. [ABSTRACT FROM AUTHOR]

Immobilized Pseudomonas fluorescens lipase enzyme was used to enrich the important polyunsaturated fatty acid (PUFA), docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) from tuna oil. Hydrolysis, esterification, and transesterification reactions were studied in detail to find out the fractionation pattern of DHA and EPA during these processes due to preferential selectivity for or against these PUFA. Hydrolysis with P. fluorescens biotype I lipase with stoichiometric amount of water content gave more than 80% of DHA and EPA in the free fatty acid (FFA) form after around 60% of hydrolysis. After some preferential specificity during the early stages of hydrolysis, P. fluorescens lipase exhibits nonselective characteristics on extended hydrolysis. Esterification of FFA extracted from the completely hydrolyzed mixture of tuna oil was found to be better with long chain fatty alcohol like octanol which lead to good enrichment (44.5% for DHA and 11.3% for EPA) and yields of the PUFA in the FFA form. Transesterification (ethanolysis) with immobilized P. fluorescens lipase enzyme resulted in good enrichment and recovery of DHA and EPA in the glyceride mixture. After around 60% of ester synthesis, 74% of (DHA + EPA) enrichment was achieved with yields of more than 90% in the glyceride mixture. [ABSTRACT FROM AUTHOR]

Hydrolysis of methyloleate was optimized using lipase from Chromobacterium viscosum immobilized on IRC-50. The optimization was studied by a statistical methodology using response surface methodology (RSM). The cumulative interactive effect of substrate, water concentration and time was studied in optimizing the hydrolysis of methyloleate. The interactive effect of substrate-time was found to be significant compared to substrate-water and time-water interactions. A well correlation was observed between the optimum values obtained from the response surface contour plots and from the quadratic regression model equation. The optimal values obtained for substrate, water and time were found to be in the experimental range chosen. [ABSTRACT FROM AUTHOR]

Aspergillus foetidus was used to produce transferases that can be utilized in the synthesis of isooligosaccharides. Maltose and corn steep liquor were found to be the best carbon and nitrogen substrates at optimum concentration of 1% and 3% respectively. Surfactant Tween 80 and metal ions including Fe2+, Zn2+, Mg2+ and Cu2+ were found to have no obvious effect on the enzyme productivity. Uncontrolled pH starting with an initial value of 5.0 gave the highest transferase productivity compared with pH controlled at constant levels and control after natural fall. The optimum temperature was found to be 30 °C. Enzyme activity increased 8 fold in reactors, with better aeration and agitation condition, as compared to shake flask. The morphology of the organism was highly dependent on the nitrogen source and had great influence on enzyme productivity. [ABSTRACT FROM AUTHOR]

As part of an integrated pest management project to study the role blue-green algae (BGA) may play in the food web of rice-field ecosystems, 14C-labelled filamentous and monocellular BGA were used as food for fish, zooplankton and benthic fauna in artificial rice fields in the form of three aquaria. 14C present in the organisms was then traced by liquid scintillation to follow the manner in which the labelled BGA were consumed by different organisms. In this study the grazing rate of fish (mud carp) was compared to that of benthic organisms and zooplankton. It was found that fish consumed the BGA at the fastest rates and in the largest amounts, followed by the benthic species and zooplankton. It was also found that filamentous BGA were consumed in higher amounts than monocellular BGA. The importance of grazing in nutrient recycling is emphasized. [ABSTRACT FROM AUTHOR]

Dry seeds of an early variety of jute (Fanduk) were X-irradiated to study the effect of selection for days to flower. Variation was induced in days to flower as evident from the high values of genotypic variances and heritability estimates in the M&sub1; generation. Asymmetric response was realized in tile M4 generation following disruptive selection- response being more towards lateness than earliness. However, significant variances for days to flower were present among both early and late selections in M4 generation. While late lines were superior to the mother variety in plant height and fibre yield/plant, early lines were inferior to the mother variety in these waits. Distribution of 15 late lines in fibre yield and plant height, classes showed that 8 lines exceeded the mother variety in fibre yield/plant and 7 of them exceeded it in plant height. In general, gradual shift towards lateness was associated with gradual shift towards greater plant height and fibre yield. Two late lines were very promising and earlier in maturity than the recommended early varieties. [ABSTRACT FROM AUTHOR]

The temperature dependence of the threshold current in electron-beam-pumped (EBP) lasers using p-type GaAs (2 1.0 cm) at 27 kV is theoretically determined, taking into account the inhomogeneous distribution and the temperature dependence of the lifetime of the excess carriers. The computed dependence is found to be in excellent agreement with the experimental observation. A comparison is then made of the result with results obtained under different assumptions to confirm positively that, in the study of the performance of these lasers, the above two features cannot be ignored.
The purpose of the present communication is to determine the influence of the inhomogeneous distribution of the minority carriers on the temperature dependence of the threshold current in EBP lasers using p-type GaAs (2 10 cm) at 27 kV, taking due consideration of the variation of the recombination lifetime with temperature. [ABSTRACT FROM AUTHOR]

The influence of wave confinement on the threshold variation with active region thickness in heterostructure injection lasers is studied by assuming a simplified model of electromagnetic wave propagation through such lasers. It is found that the threshold variation is predominantly determined by the effects of wave confinement. The analysis, though approximate, yields results in reasonable agreement with experimental observation. [ABSTRACT FROM AUTHOR]