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671.
Saurabh Sudha Dhiman Gaurav Garg Ritu Mahajan Neelam Garg Jitender Sharma 《Bioresource technology》2009,100(20):4736-4741
Xylanase alone as ‘single lay out’ (strategy I) and in combination with pectinase as ‘mixed lay out’ (strategy II) was used to investigate their bio-bleaching potentials. Strategy I was carried at 70 °C using 5 U/g of xylanase at pH 9.5 and 12.5 whereas strategy II was carried out at 70 °C using 5 U/g of each of the enzyme, respectively at pH 9.5. Bio-bleaching caused 15% and 20% less Cl2 consumption though strategy I and II, respectively over chemical bleaching. Strategy II was proved to be 35.71% more efficient in ClO2 saving than conventional method. Significant improvement in various pulp properties viz. tensile strength 25.70%, breaking length 21.80%, burst factor 20.00%, burstness 13.86%, tear factor 6.61% and tearness 18.88%, was also observed through ‘mixed lay out’ strategy. 相似文献
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673.
S Goyal PK Dubey K Tripathy R Mahajan S Pan SP Dixit P Kathiravan BP Mishra SK Niranjan RS Kataria 《Animal biotechnology》2012,23(3):194-203
In this study, approximately 3.4?kb nucleotide sequence of caprine TLR7 (Toll-like receptor 7) gene was generated from twelve different Indian goat breeds belonging to different geographical regions. Goat TLR7 gene ORF (Open Reading Frame) was found to be 3141 nucleotides long coding for 1046?amino acids similar to sheep. The sequence analysis at nucleotide level revealed goat TLR7 having 99.5% homology with sheep, followed by other livestock species. Simple Modular Architecture Research Tool (SMART) was used for the structural analysis of goat TLR7 that showed the presence of 22 leucine rich repeats (LRRs) along with single Toll/interleukin-1 receptor (TIR) domains. TIR domain, when compared, was found to be similar in ruminant species, goat, sheep, cattle, and buffalo. The phylogenetic analysis also revealed grouping of all ruminant species together, goat being closer to sheep followed by cattle and buffalo. A total of 22 polymorphic sites were observed in TLR7 gene of 24 goats representing 12 different breeds, out of which 19 were present within the coding region and three in 3'UTR. Out of the seven nonsynonymous SNPs, two were in ectodomains and one in TIR domain. Overall our results indicate substantial variation within goat TLR7 gene, which could be exploited for association with disease susceptibility. 相似文献
674.
Iwona I. Smaczynska-de Rooij Christopher J. Marklew Ellen G. Allwood Sarah E. Palmer Wesley I. Booth Ritu Mishra Martin W. Goldberg Kathryn R. Ayscough 《Molecular and cellular biology》2016,36(5):742-755
The family of dynamin proteins is known to function in many eukaryotic membrane fusion and fission events. The yeast dynamin-related protein Vps1 functions at several stages of membrane trafficking, including Golgi apparatus to endosome and vacuole, peroxisomal fission, and endocytic scission. We have previously shown that in its endocytic role, Vps1 functions with the amphiphysin heterodimer Rvs161/Rvs167 to facilitate scission and release of vesicles. Phosphoproteome studies of Saccharomyces cerevisiae have identified a phosphorylation site in Vps1 at serine 599. In this study, we confirmed this phosphorylation event, and we reveal that, like Rvs167, Vps1 can be phosphorylated by the yeast cyclin-associated kinase Pho85 in vivo and in vitro. The importance of this posttranslational modification was revealed when mutagenesis of S599 to a phosphomimetic or nonphosphorylatable form caused defects in endocytosis but not in other functions associated with Vps1. Mutation to nonphosphorylatable valine inhibited the Rvs167 interaction, while both S599V and S599D caused defects in vesicle scission, as shown by both live-cell imaging and electron microscopy of endocytic invaginations. Our data support a model in which phosphorylation and dephosphorylation of Vps1 promote distinct interactions and highlight the importance of such regulatory events in facilitating sequential progression of the endocytic process. 相似文献
675.
R Raghubir G K Patnaik B J Dhotre K B Mathur M M Dhar B N Dhawan 《Indian journal of experimental biology》1989,27(9):826-828
Opioid activity of a homologous series of met-enkephalin alkylamides was analysed. In guinea pig ileum test, the hexylamide derivative was most active, whereas the isopropylamide derivative was most potent in analgesia test. The results suggest that structural changes of this type at the C-terminus of the pentapeptide improve the opioid activity. 相似文献
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Mild and brief electrical stimulation of sites in the pretectal nucleus of rat produced analgesia (SPA) of long duration without significant aversion. Intracerebroventricular (icv) administration of 5-HT receptor antagonists methysergide (50 micrograms) and ketanserin (50 micrograms) and the dopaminergic antagonist haloperidol (50 micrograms) had no significant effect on pretectal SPA, but alpha and beta adrenoceptor antagonists phenoxybenzamine (50 micrograms) and sotalol (50 micrograms) on icv injection significantly antagonised the pretectal SPA. The results suggest that pretectal SPA involves activation of central adrenoceptors. 相似文献
679.
Coumarin-caused stimulation of rooting of cuttings ofImpatiens balsamina L. is associated with an increase in the endogenous contents of carbohydrates, total phenols and proteins. Peroxidase, IAA
oxidase and polyphenol oxidase activities also increased in coumarin treated cuttings at the time of cell division preceding
primordia formation (6–12 h after treatment). Coumarin effect on rooting as well as on related biochemical changes resembles
the effect of auxins in some ways. 相似文献
680.
Rice straw as solid residues are biomass residue materials that are not optimally used by farmers in Punjab and potentially become environmental pollutant. A large amount of rice straw (17 million tons) is generated and left as much in combine harvested rice fields in Punjab, India. It is very difficult to manage such huge amount of rice straw thus, farmers resort to burning it which leads to greenhouse gas emissions like CO2 due to open field burning and loss of rich organic matter present in the soil. Further due to imposition of restrictions by the state government, the practice of burning rice straw has now become an offense. So farmers are looking for alternatives which are economically viable. Rice straw can be effectively used as bio energy as it has about the same heating value (15 kJ kg?1) as that of wood, half that of good quality coal and one third of oil. The operational conditions required to produce high-quality chopped rice straw briquettes have not been determined and this study determined the optimal moisture content, particle size, and binder ratio required to produce rice straw briquettes. The optimized conditions resulted in formation of high-density (1030.38–1159.22 kg m?3) briquettes with durability ranging from 71.9 to 92.3% with minimum power requirement for briquetting (36.60 kW), maximum calorific value of 15.61 MJ kg?1, and minimum ash content (16.34%).Total cost of making chopped rice straw briquettes was 0.041 USD per kg and 0.00281 USD per mega joule of energy. Cost of briquetting from chopped rice straw with 10 and 20% cotton stalks was 0.050 and 0.051 USD per kg, respectively, and 0.0033 USD per mega joule of energy. Also, the briquettes prepared from chopped rice straw with and without cotton stalk as a binder were economically viable. 相似文献