693 research outputs found

    Hydrogenation of olefins by polymer-bound palladium(II) Schiff base catalyst

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    Chloromethylated poly(styrene-divinylbenzene) was modified into coordinating Schiff base bearing ligand which was subsequently complexed with palladium chloride and activated by using sodium borohydride. The polymer-supported palladium complex and activated catalyst were characterized by various techniques such as elemental analysis, X-ray photoelectron spectroscopy, atomic absorption spectroscopy, IR, far IR spectral studies, SEM and thermogravimetric analysis. Surface area measurements by BET method and swelling studies with different solvents for the catalyst were also carried out. Catalytic activity towards hydrogenation of 1-hexene, 1-heptene, 1-octene, cyclohexene, norbornadiene (nbd) and 1,5-cyclooctadiene (1,5-cod) was assessed. The influence of variation in temperature, pressure, concentration of the catalyst as well as the substrate and the nature of the solvent on the rate of the reaction was studied for a few olefins. Recycling ability of the catalyst was also evaluated. © 2009 Elsevier B.V. All rights reserved

    Report on swimbladder disorder in the honeycomb grouper, Epinephelus merra

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    Swimbladder or airbladder is a thin layered epithelial sac filled with air, lying above the alimentary canal of bony fishes that regulates buoyancy of the fish so that the specific gravity of the fish always matches the depth at which it is swimming. Swimbladder disorder (SBD) is a condition caused by sudden temperature changes impacted stomach resulting from improper feeding or due to bacterial or viral infections of the bladder characterised by inability of the fish to keep a normal upright position in water. Normally gold fishes suffer from SBD due to their globoid body shape. Fish with SBD may float on their side or their back, swim in circles or take head-down posture

    Tomorrow's Surgery: Micromotors and Microrobots

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    Surgical procedures have changed radically over the last few years due to the arrival of new technology. What will technology bring us in the future? This paper examines a few of the forces whose timing are causing new ideas to congeal from the fields of artificial intelligence, robotics, micromachining and smart materials. Intelligence systems for autonomous mobile robots can now enable simple insect level behaviors in small amounts of silicon. These software breakthroughs coupled with new techniques for microfabricating miniature sensors and actuators from both silicon and ferroelectric families of materials offer glimpses of the future where robots will be small, cheap and potentially useful to surgeons. In this paper we relate our recent efforts to fabricate piezoelectric micromotors in an effort to develop actuator technologies where brawn matches to the scale of the brain. We discuss our experiments with thin film ferroelectric motors 2mm in diameter and larger 8mm versions machined from bulk ceramic and sketch possible applications in the surgical field.MIT Artificial Intelligence Laborator

    Antibacterial activity of aqueous extract from selected macroalgae of southwest coast of India

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    Aqueous extract of seven species of marine macroalgae were screened for their antimicrobial potency against ten pathogenic bacterial strains. Ulva fasciata, Gracilaria corticata, Sargassum wightii and Padina tetrastromatica showed significantly higher activity against 70% of the tested bacterial isolates. The maximum zone of inhibition was noted for the red alga G.corticata against Proteus mirabilis (17mm) and brown alga P. tetrastromatica against the pathogens Staphylococcus aureus and Vibrio harveyi (15mm). The general trend of inhibitory activity was higher towards Gram negative bacteria

    Polymicrobial skin lesions in the red spot emperor, Lethrinus lentjan (Lacepede 1802) during mass incursion towards shore along Kanyakumari coast, south India

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    Mass incursion of fishes with polymicrobial skin lesions, fin erosions and scale loss was recorded in the red spot emperor Lethrinus lentjan (Lacepede 1802) along the Kanyakumari coast, south India during August 2009. An estimated 2.5 t of fish, mostly the red spot emperors were found to migrate in live condition to the shore areas in a stressful state. Microbiological analyses of tissue from sampled fishes revealed three distinct types of bacterial colonies forming 5.2 x 105 CFU g-1 of the infected tissues. The predominant bacterial colonies were characterized as Aeromonas sp. (70.0%) followed by Flavobacterium sp. (20%) and Vibrio sp. (10%). The Aeromonas isolate was highly susceptible to norfloxacin while the Flavobacterium and Vibrio isolates were susceptible to chloramphenicol. The Aeromonas and Vibrio isolates exhibited protease and amylase enzyme activities in vitro, suggesting their possible role in the progression of skin lesions and scale loss. The possibilities of ambient unknown stressors weakening the fish and subsequent infections by these bacterial isolates are discussed

    On Q*s - regular spaces and Q*s - normal spaces

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    The notion of Q* - open sets in a topological space was introduced by Murugalingam and Lalitha [7]. We introduce the notion of Q*s - regular, Q*s - normal, s*Q* - normal and obtain some characterizations Q*s - regularity and Q*s – normality, s*Q* - normal

    AUTOMATIC DETECTION OF DIABETIC RETINOPATHY THROUGH OPTIC DISC USING MORPHOLOGICAL METHODS

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    This paper proposes a method for the automatic detection of optic disc in retinal images. In the diagnosis and grading, the essential step is recognition of optic disk for diabetic retinopathy. The analysis of directional cross section profile focused on the local maximum pixel of pre-processed image is realized by the proposed method using optic disc detection. Each profile is implemented by peak detection and property like shape, size and height of the peak are estimated. The statistical measure of the estimated values for the attributes, where the orientation of the cross-section changes the constitute feature used in morphological classification to exclude encourages candidates. The result is to find the patient is affected by diabetics or not.Keywords: Diabetic retinopathy, Optic disk, Naives Bayes algorithm, Local maximum region

    POST-HARVEST SOIL TEST VALUES (PHSTVS) PREDICTION EQUATION FOR A PEARL MILLET BASED CROPPING SEQUENCE ON AN INCEPTISOL

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    Analyzing soil samples for prescribing soil test based fertilizer doses after each crop in a sequence is time, labour and energy consuming and involves additional cost. With a view to develop post-harvest soil-test values (PHSTVs) prediction equations with multiple linear regression, field experiments were conducted during 2015-16 by adopting Inductive cum Targeted yield model, on an Inceptisol (Vertic Ustropept) with pearl millet under integrated plant nutrition system (IPNS). The experiment was laid out in a fractional factorial design comprising twenty-four treatments. When grain yield was considered, the predictability values of KMnO4-N, Olsen-P, and NH4OAc-K under NPK plus FYM @ 12.5 t ha-1 treatment were 98.4, 97.5, and 98.1%, respectively. When uptake was considered, the predictability values of KMnO4-N, Olsen-P, and NH4OAc-K under NPK plus FYM @ 12.5 t ha-1 treatment were 98.4, 97.6, and 98.1%, respectively. Significant R2-values (>0.65) were recorded for these regression equations which could be used with confidence for the prediction of post-harvest KMnO4- N, Olsen-P and NH4OAc-K. The data on observed and predicted soil test values of available N, P and K were in good agreement with each other, proving the validity of the post-harvest soil test values prediction equations as evidenced by highly significant correlation
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