Fatty acid profile of fish scale of Catla catla

Fish scales are useful to ichthyologists for the purposes of classification, identification, age determination and history study. The fatty acid profile of the hexane extracts of the fresh water fish scale of Catla catla were analyzed by gas chromatography. Fish scales were collected from a local fish market, Chidambaram. The fatty acid profile was detected in the scales, with the following fatty acids dominating: 16:0, 18:0, 18:1, 18:2, 18:3 and 18:4. The use of fatty acid profiling in fish scales has the potential for stock identification in addition to the identification of fish farm escapees.Key words: Fish scales, fatty acid, gas chromatography, Catla catla

Ultrafine grained materials through mechanical processing: an assessment

In this paper severe plastic deformation (SPD) and friction stir processing/ welding are examined. The structural changes due to SPD are reflected in improved mechanical properties. Advantages of SPD are pointed out. Within the SPD technique, a number of approaches are possible, e.g., equi-channel angular pressing/extrusion, high pressure torsion, accumulative roll bonding/fold - roll process, reciprocating extrusion - compression, cyclic close die forging, repetitive corrugation and straightening. Analyses available are elementary and often assume uniform stress and strain distribution. These processes are easily adapted to suit standard metal working equipment fitted with inexpensive devices and tools. However, scaling up the processes to handle large billets and achieve large tonnage production is difficult. In the near future, medium and small-scale industrial production only is likely. Friction stir process, a solid state technique for joining similar or dissimilar materials of equal or different thickness, has some key metallurgical, environmental and energy benefits. It is already being considered for applications in aerospace and automotive industries. Significant improvements in surface properties and superplastic flow have been established in friction stir processed materials. Velocity of tool movement and power input needed for fast rotation of the tool are the major variables. Since significant temperature rise is there during processing, in a proper analysis, the boundary conditions arising from thermal and mechanical constraints have to be satisfied simultaneously, which is an extremely difficult. A few key issues have to be addressed before large-scale production can be attempted. An integral approach that takes into account the total system of material, design, mechanics and component forming is likely to lead to industrially relevant solutions

Ultrafine grained materials through mechanical processing: An assessment

In this paper severe plastic deformation (SPD) and friction stir processing/ welding are examined. The structural changes due to SPD are reflected in improved mechanical properties. Advantages of SPD are pointed out. Within the SPD technique, a number of approaches are possible, e.g., equi-channel angular pressing/extrusion, high pressure torsion, accumulative roll bonding/fold - roll process, reciprocating extrusion – compression, cyclic close die forging, repetitive corrugation and straightening. Analyses available are elementary and often assume uniform stress and strain distribution. These processes are easily adapted to suit standard metal working equipment fitted with inexpensive devices and tools. However, scaling up the processes to handle large billets and achieve large tonnage production is difficult. In the near future, medium and small-scale industrial production only is likely. Friction stir process, a solid state technique for joining similar or dissimilar materials of equal or different thickness, has some key metallurgical, environmental and energy benefits. It is already being considered for applications in aerospace and automotive industries. Significant improvements in surface properties and superplastic flow have been established in friction stir processed materials. Velocity of tool movement and power input needed for fast rotation of the tool are the major variables. Since significant temperature rise is there during processing, in a proper analysis, the boundary conditions arising from thermal and mechanical constraints have to be satisfied simultaneously, which is an extremely difficult. A few key issues have to be addressed before large-scale production can be attempted. An integral approach that takes into account the total system of material, design, mechanics and component forming is likely to lead to industrially relevant solutions

Current redistribution model of anomalous resistance behaviour in superconductor-topological insulator heterostructures

Anomalous resistance upturn and downturn have been observed on the topological insulator (TI) surface in superconductor-TI (NbN-Bi1.95Sb0.05Se3) heterostructures at ~ mm length scales away from the interface. Magnetotransport measurements were performed to verify that the anomaly is caused due to the superconducting transition of the NbN layer. The possibility of long range superconducting proximity effect due to the spin-polarized TI surface state was ruled out due to the observation of similar anomaly in NbN-Au and NbN-Al heterostructures. It was discovered that the unusual resistance jumps were caused due to current redistribution at the superconductor-TI interface on account of the geometry effects. Results obtained from finite element analysis using COMSOL package has validated the proposed current redistribution (CRD) model of long range resistance anomalies in superconductor-TI and superconductor-metal heterostructures.Comment: 37 pages (including references), 17 figure

Effect of dietary supplementation of cassia auriculata leaf powder on growth and immune responses of milkfish, Chanos chanos

A 30 days feeding trial was conducted to evaluate the effects of Cassia auriculata leaf powder on growth and immunomological parameters of the juveniles of Milkfish, Chanos chanos and disease resistance against Vibrio anguillarum. The juvenile fishes with an average weight of 20±3 g were stocked in four treatments each with three replicates. Four practical diets were prepared with graded level of Cassia auriculata leaf powder (CAL) at the rate of 0%, 0.5%, 1% and 1.5% and fed to four treatments respectively named as CAL0, CAL0.5, CAL1 and CAL1.5. At the end of the experiment blood samples were collected for immunological parameters. After sampling, the remaining fishes were challenged with 0.1 mL of virulent V. anguillarum suspension at a concentration of 107 CFU mL-1 and mortality was observed for 7 days. Post challenge sampling was performed for the collection of blood samples. The growth parameters such as Weight gain%, SGR%, PER were positively affected by Cassia auriculata leaf powder incorporated diet. Higher weight gain %, SGR% and PER were noticed in CAL1.5 group followed by CAL1, CAL0.5 and CAL0. The respiratory burst, lysozyme and phagocytic activities were increased with increasing level of CAL in the diet which indicates better immune response of the fishes fed with CAL. The higher respiratory burst (0.522 ± 0.03), lysozyme (70.07 ± 1.57) and phagocytic (52.91 ± 1.76) activitieswere observed in CAL1.5, CAL1 and CAL1.5 groups respectively during pre-challenge and post challenge. There was significant difference in the survival rate of control (CAL0) and CAL incorporated diet fed groups (P<0.05). Maximum survival was witnessed in CAL1 followed by CAL1.5 and least survival was in CAL0 group. The results indicate that diets supplemented with 1% CAL potentially enhance the immune system and effectively protects the host against V. anguillarum infection and thereby improve the survivability of the fish against this dreadful pathogen

ELECTROCHEMICAL DETERMINATION OF NITRO EXPLOSIVE (HNS) USING GLASSY CARBON ELECTRODE

A glassy carbon electrode (GC) exhibited an attractive performance for the detection and determination of a nitro compound like 1,2- Bis(2,4,6-trinitrophenyl)ethylene (HNS). Cyclic voltammetry, differential pulse and square wave voltammetry were used in a combined way to identify the electrochemical characteristics and to optimize the conditions for detection. For calibrating and estimating HNS, square- wave voltammetry was mainly used. The HNS shows a well-defined peak at in the dimethy sulfoxide (DMSO) containing Tetrabutyl Ammonium Bromide (TBABr) medium. The existence of peak at -0.10 V showed good peak and high current response

Evaluation of the Quality of Commercial Fish Feeds in India with Respect to Microbiological Parameters

This paper describes the first comprehensive study of the quality of commercial fish feeds in India with regard to microbiological indices. Quality of feed is an important parameter that has a direct impact on the outcome of any aquaculture system. Microbiological parameters such as total plate count (TPC), Escherichia coli (CFUg-1), coliformes (CFUg-1), Enterobacteriaceae (CFUg-1) and yeast and mould (CFUg-1) counts were analysed using 3M™ Petrifilm™ as per guidelines. The TPC ranged from 2.0 × 102 to3.13 × 104 CFUg-1 in different feeds. Presence of E. coli was detected in one of the feeds with 1.15×102 CFUg-1. Coliform bacteria were not detected in any of the feeds. Enterobacteriaceae was present in three feeds in the range of 5.45 × 102 to 1.58×103 CFUg-1. Yeast and mould count ranged from <10 to 1.68 × 104 CFUg-1 in the feeds analyzed. The results obtained from the present study indicate that the feeds were contaminated with micro-organisms. As far as Indian scenario is concerned, there exist several feed companies which do not comply with the quality regulations and specifications as laid down by the Bureau of Indian Standards (BIS). In addition, specifications are not available for aqua feeds regarding the acceptable levels of microbiological parameters. Hence the present study calls for a standardized code of quality to be observed by feed manufacturing companies for quality products

FSL-BM: Fuzzy Supervised Learning with Binary Meta-Feature for Classification

This paper introduces a novel real-time Fuzzy Supervised Learning with Binary Meta-Feature (FSL-BM) for big data classification task. The study of real-time algorithms addresses several major concerns, which are namely: accuracy, memory consumption, and ability to stretch assumptions and time complexity. Attaining a fast computational model providing fuzzy logic and supervised learning is one of the main challenges in the machine learning. In this research paper, we present FSL-BM algorithm as an efficient solution of supervised learning with fuzzy logic processing using binary meta-feature representation using Hamming Distance and Hash function to relax assumptions. While many studies focused on reducing time complexity and increasing accuracy during the last decade, the novel contribution of this proposed solution comes through integration of Hamming Distance, Hash function, binary meta-features, binary classification to provide real time supervised method. Hash Tables (HT) component gives a fast access to existing indices; and therefore, the generation of new indices in a constant time complexity, which supersedes existing fuzzy supervised algorithms with better or comparable results. To summarize, the main contribution of this technique for real-time Fuzzy Supervised Learning is to represent hypothesis through binary input as meta-feature space and creating the Fuzzy Supervised Hash table to train and validate model.Comment: FICC201