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321.
Prasanna K. R. Allu B. Chakraborty Madhusudan Das Nitish R. Mahapatra Sajalendu Ghosh 《Aquaculture International》2014,22(2):775-782
High consumer preference together with its polyculture potential has undoubtedly driven Rohu (Labeo rohita) and Catla (Catla catla) to top the list of the most preferred fishes among the Indian major carps. Commonly found in these fishes are hybrids that can be natural or man-made. Increasing emphasis on biodiversity issues has necessitated proper stock management of these through molecular genetics techniques. Also with few morphological differences that can be used to differentiate wild types and hybrids properly, the problem demands a straightforward molecular approach. Here, we report a simple PCR-based technique that can differentiate the hybrid variety from wild types easily using three different microsatellite markers. Three sets of primers were used to amplify three different microsatellite markers from the genomic DNA isolated from pectoral fins. When the PCR products using all three primer sets were analyzed, ‘hybrid–Rohu’ could be distinguished from wild types. Whereas the hybrid–Rohu DNA yielded specific PCR products with all three primer pairs, only two PCR products were obtained either from wild-type Catla DNA (by primer sets 1 and 2) or from wild-type Rohu DNA (by primer sets 1 and 3). This study clearly demonstrates that a simple PCR-based technique will help the fish breeders and hatcheries to identify and differentiate suspected hybrid–Rohu carp from the wild types within a few hours. 相似文献
322.
Arun Ghosh Richard S. Carran Anita J. Grosvenor Santanu Deb-Choudhury Stephen R. Haines Jolon M. Dyer 《Fibers and Polymers》2016,17(1):9-14
The poultry meat processing industry produces large amounts of feather meal, which is traditionally used as lowvalue plant fertilizer or fish nutrient. A higher value application for feather meal is described in this paper - a thermal blending and compression molding method to create compostable composites out of environmentally friendly materials: feather meal, glycerol, and a biodegradable copolymer of methyl vinyl ether and maleic anhydride (MVEMA). The composite’s mechanical, microstructural and chemical characteristics are described. Feather meal plasticized only with glycerol is mechanically fragile, with average tensile strength of 1.7 MPa, Young’s modulus of 296 MPa and strain-at-failure of 0.6 %. With the addition of MVEMA copolymer, feather meal is transformed into a ductile plastic composite, with tensile modulus reduced 2- to 5-fold and strain-at-failure increased 4- to 25-fold. These properties are ideal for creating feather mealbased compostable bioplastics for agricultural and industrial applications. 相似文献
323.
Fibres being the structural unit of a yarn, its nature, composition and arrangement can influence structure and properties. The performance of yarn changes with arrangement of its constituent fibres. Arrangement of fibres in a yarn being system specific, different spinning system results different arrangement of fibres causing variation in product performance. A change in the arrangement of fibres in an already formed yarn can be brought about by suitable physical and/or chemical treatment. A treatment to remove a component is expected to cause changes in final arrangement of fibres in a yarn. In the present study, polyester/PVA blended yarn was modified through dissolution of the later component. The resultant change in structural arrangement on dissolution was assessed by the change in radial packing distribution of fibres. Migration index, helped in identifying the location that was influenced more in the redistribution. In the parent yarn, PVA had a preferential tendency to predominate near the core. On dissolution of PVA, creation of open space was expected and collapsing of the structure led to a possible rearrangement of fibres and reduction in diameter of yarn. Fibre denier, blend ratio and twist factor were also found to influence packing density both in parent and modified yarn. Unlike published reports, interestingly, an increase in fibre packing density was observed on dissolution of PVA. Average packing density in parent yarn was found to lie at a yarn radius between 0.07 mm to 0.09 mm while for the modified yarn it was between 0.05 mm to 0.07 mm. 相似文献
324.
Samik Bhattacharya Jayadri S. Ghosh Dipak K. Sahoo Nrisingha Dey Amita Pal 《Annals of Forest Science》2010,67(6):611-611
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• The search for alternative fiber resources is receiving worldwide attention for the potential role of these fibers in climate
and forest restoration. Among bamboos, Bambusa balcooa is generally preferred for industrial use due to its rapid growth, excellent flexibility and tensile strength. The aim of
this study is to establish a non-invasive and efficient method of screening superior fiber quality from the wild gene pool
of B. balcooa. 相似文献
325.
Sujan Biswas Arunava Ghosh Abhas Kumar Sinha Prabir Mukhopadhyay 《Communications in Soil Science and Plant Analysis》2016,47(7):851-862
A 12-week laboratory incubation experiment was conducted to determine the effect of chemical composition of residues of nine plant species on their cumulative net nitrogen (N) mineralization in soil under submergence (SUB) and field capacity (FC) water conditions. The influence of residues and of water regimes on residue-N released over time was significant. Net mineralization was higher in FC than SUB especially in later periods, although differences either among soil water levels or among species were not significant in all the periods sampled. Net N release had significant correlations with initial N and ratios of carbon, lignin or polyphenol or the (lignin + polyphenol) to N concentration of residues under two water conditions. (Lignin + polyphenol):N ratio in SUB and carbon/nitrogen (C:N) ratio in FC showed highest correlations with N mineralization in all periods and explained 64.1% variation in N mineralization from residues under SUB and 64.5% under FC after 2 and 8 weeks, respectively. 相似文献
326.
327.
328.
Ghosh S Rawat P Velusamy R Joseph D Gupta SC Singh BP 《Veterinary research communications》2005,29(2):123-135
An indirect enzyme-linked immunosorbent assay (ELISA) using 27 kDa glycoprotein of Fasciola gigantica has been evaluated for its potential use in the diagnosis of bovine fasciolosis. Following experimental infection of rabbits, F. gigantica infection-induced antibodies were isolated and later used as ligands in affinity chromatography for isolation of infection-induced antibody-specific proteins. Among the five infection-specific proteins isolated, a glycoprotein of 27 kDa was later isolated by second-step purification using concanavalin A matrix. In crossbred cattle receiving different doses of infection (100, 200 and 400 metacercariae), the anti-27 kDa antibodies were detected as early as the 2nd week post infection. No direct correlation between initial dose, antibody response and fluke establishment was recorded. No cross-reaction was noted with the sera of goats experimentally infected with Paramphistomum epiclitum. ELISA with the 27 kDa glycoprotein could be a feasible diagnostic tool for the early detection of bovine fasciolosis. 相似文献
329.
The composition and structure of the intervertebral discs have been studied in a group of six four-month-old beagles which were full or half-siblings. The animals were raised in identical environment and were comparable weight and size at sacrifice. Collagen, hexosamine, uronic acid, sialic acid and non-collagenous protein analysis (via indirect method) were performed on the nucleus pulposus (NP), transitional zone (TZ) and a annulus fibrosus (AF) of the discs for the lumbo-sacral, lumbar and thoracic spinal levels. Parallel histochemical and morphological examinations of the discs were also performed. The knee joint meniscus, and articular cartilage was also examined for the components described. The results of the analysis for the discs revealed that within this single age group there co-exist two statistically different compositional states. These differences reside largely in the NP and TZ regions and from the analytical values are interpreted as indicating the chondroid and non-chondroid conditions. No such compositional variation was observed for articular cartilage and fibrocartilage (knee joint menisci). 相似文献
330.
Immunoprotective Efficacy of a Purified 39 kDa Nymphal Antigen of Hyalomma anatolicum anatolicum 总被引:2,自引:0,他引:2
Soluble nymphal antigens (HNAg) were purified by immunoaffinity chromatography using CNBr-activated Sepharose 4B coupled with immunoglobulin ligands from animals immunized with HNAg and 69–71% protected against challenge infestations, and 8% recovery of the purified protein (Aff-HNAg) was obtained. Following immunization of crossbred calves (Bos indicus×Bos taurus) with 1600 g of Aff-HNAg in three divided doses, significant rejections of larvae (p<0.001, 84.2%), nymphs (p<0.05, 61.4%) and adults (p<0.05, 58.7%) were recorded. No significant changes were recorded in the engorgement weights of the larvae and nymphs, but there was a significant (p<0.05) reduction in the weight of the engorged adults. Immunization conferred a significant decrease in the numbers of resultant nymphs (p<0.001) and adults (p<0.001) that had fed on the immunized animals. SDS-PAGE analysis identified a 39 kDa protein, previously isolated from larvae of Hyalomma anatolicum anatolicum, as the antigen responsible for the induction of resistance against all the stages of the tick. 相似文献
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