Comparative basal transcriptome profiles of the olfactory rosette and gills of Atlantic salmon (Salmo salar) unveil shared and distinct immunological features

The molecular repertoire of the mucosa-associated lymphoid tissue (MALT) in the olfactory rosette in most teleost fish is unknown. Here we present the basal transcriptome of the olfactory rosette of Atlantic salmon (Salmo salar). To investigate its mucosal immune features, we performed a comparative transcriptomic analysis with the gills, one of the most studied organs possessing MALT. Pathway enrichment revealed that cytokine-cytokine interaction and the neuroactive ligand-receptor interaction pathways were at the core of the shared similarity between the two organs. The immunological features of the two organs were further characterised by the overrepresentation of several immune-related pathways, particularly important for pathogen recognition. The immunological differences between the two organs were underlined with the differential regulation of markers for interleukins, extracellular matrix, antimicrobial peptides, and complement. The basal transcriptome of Atlantic salmon olfactory rosette is a valuable molecular toolbox that will advance our understanding of nasal immunity in teleost fish.publishedVersio

Internal Ballistic Code for Solid Rocket Motors using Minimum Distance Function for Grain Burnback

A computer code has been developed for internal ballistic performance evaluation of solid rocket motors, using minimum distance function (MDF) approach for prediction of geometry evolution. This method can handle any complex geometry without the need to define different geometrical shapes and their evolution as used in several existing analytical geometry evolution-based methodologies. The code is validated with both experimental results published in literature, as well as for solid rocket motors of tactical and strategic missiles and a very good match is obtained with static test results. The output of the code gives p-t (pressure-time) curve as well as the detailed parameters of the flow along the axial direction, and geometries in the form of mesh file, which can be further used as input to codes for CFD analysis.Defence Science Journal, Vol. 65, No. 3, May 2015, pp.181-188, DOI: http://dx.doi.org/10.14429/dsj.65.830

PRODUCTION, CHARACTERIZATION AND PURIFICATION OF ALKALINE PROTEASE FROM ALCALIGENES sp., AND ITS APPLICATION IN DETERGENT INDUSTRY

Proteases are enzymes well known for their wide range industrial applications such as food, detergent, pharmaceutical etc. The aim of the present work was to study the production, purification and application of alkaline protease from the strain Alcaligenes sp. (MTCC 9730). Batch and fed batch fermentation were used as the production strategies. The optimum temperature and pH for the production of enzyme was found to be 55°C and pH 9 respectively. Ca2+ increased the activity, Cu2+ and Mg2+ mildly inhibited and by Zn2+ strongly inhibited the activity. The protease enzyme was purified using Ammonium sulphate precipitation and maximum activity of 60 U/ml was found at 70percent saturation. Alkaline protease is known to be an active ingredient of the commercial detergents. The enzyme was used to study its compatibility with other detergents and its ability to remove the protein stain. Keywords: Alkaline protease, Alcaligenes sp, fermentation, purification, detergent

Diversification of the expanded teleost-specific toll-like receptor family in Atlantic cod, Gadus morhua.

BACKGROUND: Toll-like receptors (Tlrs) are major molecular pattern recognition receptors of the innate immune system. Atlantic cod (Gadus morhua) is the first vertebrate known to have lost most of the mammalian Tlr orthologues, particularly all bacterial recognising and other cell surface Tlrs. On the other hand, its genome encodes a unique repertoire of teleost-specific Tlrs. The aim of this study was to investigate if these duplicate Tlrs have been retained through adaptive evolution to compensate for the lack of other cell surface Tlrs in the cod genome. RESULTS: In this study, one tlr21, 12 tlr22 and two tlr23 genes representing the teleost-specific Tlr family have been cloned and characterised in cod. Phylogenetic analysis grouped all tlr22 genes under a single clade, indicating that the multiple cod paralogues have arisen through lineage-specific duplications. All tlrs examined were transcribed in immune-related tissues as well as in stomach, gut and gonads of adult cod and were differentially expressed during early development. These tlrs were also differentially regulated following immune challenge by immersion with Vibrio anguillarum, indicating their role in the immune response. An increase in water temperature from 4 to 12°C was associated with a 5.5-fold down-regulation of tlr22d transcript levels in spleen. Maximum likelihood analysis with different evolution models revealed that tlr22 genes are under positive selection. A total of 24 codons were found to be positively selected, of which 19 are in the ligand binding region of ectodomain. CONCLUSION: Positive selection pressure coupled with experimental evidence of differential expression strongly support the hypothesis that teleost-specific tlr paralogues in cod are undergoing neofunctionalisation and can recognise bacterial pathogen-associated molecular patterns to compensate for the lack of other cell surface Tlrs

Investigating Tantalum as a Plasma-Facing Component for Nuclear Fusion Reactors

Nuclear fusion is a potential source for producing unlimited environment-friendly energy. Tungsten (W) is selected as the primary candidate material for plasma facing component in nuclear fusion reactors due to its high melting temperature (3695 K), low sputtering erosion yield and strong mechanical properties. However, recent investigations on W have confirmed that it undergoes severe surface morphology changes during low energy He plasma and/or ion irradiation similar to a harsh fusion environment. Additionally, our previous studies indicate that tantalum (Ta) may show better resistance to the harsh radiation environment and is therefore worthy of investigation. Hydrogen retention properties, specifically deuterium (D) retention in Ta, are not well documented and are extremely important safety issue for fusion reactors. Consequently, we exposed Ta to a fusion-like environment of low-energy D ions and performed thermal desorption spectroscopy (TDS). Then, the samples were rapidly loaded (to avoid possible surface oxidation) into another vacuum chamber where we performed the thermal desorption spectroscopy measurements. Our investigations indicate two binding energy values for D in Ta, i.e. 1.8 eV and 2.1 eV. We observe a higher binding energy and a higher retention rate for D in Ta than W. We also observed that our results are consistent with theoretical predictions based on the absorption of D in Ta. Our preliminary results indicate that Ta shows better resistance to nanostructure formation (fuzz) than W in a fusion environment. However, this is still an open question and part of ongoing investigations

Nasal responses to elevated temperature and Francisella noatunensis infection in Atlantic cod (Gadus morhua)

We report the histological and transcriptomic changes in the olfactory organ of Atlantic cod exposed to Francisella noatunensis. Experimental infection was performed at either 12oC or 17oC. Infected fish presented the classic gross pathologies of francisellosis. Nasal morpho-phenotypic parameters were not significantly affected by temperature and infection, except for the number of mucus cells in the 12oC group seven weeks after the challenge. A higher number of genes were altered through time in the group reared at 17oC. At termination, the nasal transcriptome of infected fish in both groups was similar to the control. When both infected groups were compared, 754 DEGs were identified, many of which were involved in signalling, defence, transmembrane and enzymatic processes. In conclusion, the study reveals that elevated temperature could trigger responses in the olfactory organ of Atlantic cod and shape the nasal response to F. noatunensis infection.Nasal responses to elevated temperature and Francisella noatunensis infection in Atlantic cod (Gadus morhua)publishedVersio

Deltamethrin resistance in the salmon louse, Lepeophtheirus salmonis (Krøyer): Maternal inheritance and reduced apoptosis

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Gene Expression in Embryos From Norwegian Red Bulls With High or Low Non Return Rate: An RNA-Seq Study of in vivo-Produced Single Embryos

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