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981.
Cluster Computing - With the exponential proliferation of cloud services, the decision of trustworthy cloud service selection has become tremendously challenging nowadays. It demands an accurate... 相似文献
982.
Seda Yerlikaya Madeleine Meusburger Romika Kumari Alexandre Huber Dorothea Anrather Michael Costanzo Charles Boone Gustav Ammerer Pavel V. Baranov Robbie Loewith 《Molecular biology of the cell》2016,27(2):397-409
Nutrient-sensitive phosphorylation of the S6 protein of the 40S subunit of the eukaryote ribosome is highly conserved. However, despite four decades of research, the functional consequences of this modification remain unknown. Revisiting this enigma in Saccharomyces cerevisiae, we found that the regulation of Rps6 phosphorylation on Ser-232 and Ser-233 is mediated by both TOR complex 1 (TORC1) and TORC2. TORC1 regulates phosphorylation of both sites via the poorly characterized AGC-family kinase Ypk3 and the PP1 phosphatase Glc7, whereas TORC2 regulates phosphorylation of only the N-terminal phosphosite via Ypk1. Cells expressing a nonphosphorylatable variant of Rps6 display a reduced growth rate and a 40S biogenesis defect, but these phenotypes are not observed in cells in which Rps6 kinase activity is compromised. Furthermore, using polysome profiling and ribosome profiling, we failed to uncover a role of Rps6 phosphorylation in either global translation or translation of individual mRNAs. Taking the results together, this work depicts the signaling cascades orchestrating Rps6 phosphorylation in budding yeast, challenges the notion that Rps6 phosphorylation plays a role in translation, and demonstrates that observations made with Rps6 knock-ins must be interpreted cautiously. 相似文献
983.
Neelam Mangwani Supriya Kumari Sudhir K. Shukla T. S. Rao Surajit Das 《Current microbiology》2014,68(5):648-656
Biofilm-forming marine bacterium Paenibacillus lautus NE3B01 was isolated from a mangrove ecosystem, Odisha, India. This isolate formed a swarming type of colony pattern on the solid culture medium with 0.5–2 % agar. Phase contrast microscopy study of a growing colony of P. lautus on solid media and swarming pattern revealed the existence of two phenotypically distinct cells (i.e. cocci and rods) across the colonies. However, in actively growing planktonic culture, only rod-shaped cells were observed. Biofilm growth studies (crystal violet assay) with the isolate showed significant biofilm formation by 6 h, and the detachment phase was observed after 18 h. Biofilm parameters (such as total biomass, roughness coefficient, biofilm thickness, etc.) of 24-h-old P. lautus biofilm were studied by confocal scanning laser microscopy (CSLM). The CSLM study showed that P. lautus formed a biofilm with an average thickness of 14.8 ± 2.6 μm, a high roughness coefficient (0.379 ± 0.103) and surface to bio-volume ratio (4.59 ± 1.12 μm2/μm3), indicating a highly uneven topography of the biofilm. This also indicates that the 24-h-old biofilm is in dispersal phase. Scanning electron microphotographs of P. lautus also supported the existence of two distinct phenotypes of P. lautus. The current findings suggest that P. lautus has two vegetative phenotypes and to decongest the overcrowded biofilm the bacterium can switch over to motile rods from nonmotile cocci and vice versa. 相似文献
984.
Plasmonics - In this paper, a detailed numerical investigation has been carried out to find the effect of stress on the optical performances of hybrid plasmonic waveguides (HPWs) operating at 1550... 相似文献
985.
Binu Mani Tripathi Priyanka Kumari Kela P. Weber Anil Kumar Saxena Dilip Kumar Arora Rajeev Kaushik 《Indian journal of microbiology》2014,54(1):65-73
Microbial communities play a vital role in maintaining soil health. A multiphasic approach to assess the effect of pulp and paper mill effluent on both the structure and function of microbial soil communities is taken. Bacterial communities from agricultural soils irrigated with pulp and paper mill effluent were compared to communities form soils irrigated with well water. Samples were taken from fields in the state of Uttarakhand, India, where pulp and paper mill effluent has been used for irrigation for over 25 years. Comparisons of bacterial community structure were conducted using sequencing of the 16S rRNA gene from both isolates and clone libraries attained from the soil. Community-level physiological profiling was used to characterize the functional diversity and catabolic profile of the bacterial communities. The multiphasic approach using both physiological and molecular techniques proved to be a powerful tool in evaluating the soil bacterial community population and population differences therein. A significant and consistent difference in the population structure and function was found for the bacterial communities from soil irrigated with effluent in comparison to fields irrigated with well water. The diversity index parameters indicated that the microbial community in pulp and paper mill effluent irrigated fields were more diverse in both structure and function. This suggests that the pulp and paper mill effluent is not having a negative effect on the soil microbial community, but in fact may have a positive influence. In terms of soil health, this finding supports the continued use of pulp and paper mill effluent for irrigation. This is however only one aspect of soil health which was evaluated. Further studies on soil resistance and robustness could be undertaken to holistically evaluate soil health in this situation. 相似文献
986.
Avinash Kumar Vijay Rani Rajpal Ambika Rachayya Mallikarjun Devarumath Amita Kumari Rakesh Thakur Manju Chaudhary Pradeep Pratap Singh Shiv Murat Singh Chauhan Soom Nath Raina 《Physiology and Molecular Biology of Plants》2021,27(4):727
Picrorhiza kurroa is a medicinally important, high altitude perennial herb, endemic to the Himalayas. It possesses strong hepato-protective bioactivity that is contributed by two iridoid picroside compounds viz Picroside-I (P-I) and Picroside-II (P-II). Commercially, many P. kurroa based hepato-stimulatory Ayurvedic drug brands that use different proportions of P-I and P-II are available in the market. To identify genetically heterozygous and high yielding genotypes for multiplication, sustained use and conservation, it is essential to assess genetic and phytochemical diversity and understand the population structure of P. kurroa. In the present study, isolation and HPLC based quantification of picrosides P-I and P-II and molecular DNA fingerprinting using RAPD, AFLP and ISSR markers have been undertaken in 124 and 91 genotypes, respectively. The analyzed samples were collected from 10 natural P. kurroa Himalayan populations spread across four states (Jammu & Kashmir, Sikkim, Uttarakhand and Himachal Pradesh) of India. Genotypes used in this study covered around 1000 km geographical area of the total Indian Himalayan habitat range of P. kurroa. Significant quantitative variation ranging from 0.01 per cent to 4.15% for P-I, and from 0.01% to 3.18% in P-II picroside was observed in the analyzed samples. Three molecular DNA markers, RAPD (22 primers), ISSR (15 primers) and AFLP (07 primer combinations) also revealed a high level of genetic variation. The percentage polymorphism and effective number of alleles for RAPD, ISSR and AFLP analysis varied from 83.5%, 80.6% and 72.1%; 1.5722, 1.5787 and 1.5665, respectively. Further, the rate of gene flow (Nm) between populations was moderate for RAPD (0.8434), and AFLP (0.9882) and comparatively higher for ISSR (1.6093). Fst values were observed to be 0.56, 0.33, and 0.51 for RAPD, ISSR and AFLP markers, respectively. These values suggest that most of the observed genetic variation resided within populations. Neighbour joining (NJ), principal coordinate analysis (PCoA) and Bayesian based STRUCTURE grouped all the analyzed accessions into largely region-wise clusters and showed some inter-mixing between the populations, indicating the existence of distinct gene pools with limited gene flow/exchange. The present study has revealed a high level of genetic diversity in the analyzed populations. The analysis has resulted in identification of genetically diverse and high picrosides containing P. kurroa genotypes from Sainj, Dayara, Tungnath, Furkia, Parsuthach, Arampatri, Manvarsar, Kedarnath, Thangu and Temza in the Indian Himalayan region. The inferences generated in this study can be used to devise future resource management and conservation strategies in P. kurroa.Supplementary InformationThe online version contains supplementary material available at 10.1007/s12298-021-00972-w. 相似文献
987.
Ajayrajsinh R. Zala Dhanji P. Rajani Premlata Kumari 《Journal of biochemical and molecular toxicology》2023,37(1):e23231
A series of novel piperazine based cinnamic acid bearing coumarin derivatives were designed and synthesized by piperazine based cinnamic acids esterification with 4-hydroxycoumarin and characterized by various spectral techniques like infrared, 1H nuclear magnetic resonance (NMR), 13C NMR, and mass. The novel bioactive compounds (7a-7m) screen their potential against different bacterial and fungal strains. Compound 7g (minimum inhibitory concentration [MIC] = 12.5 µg/ml) exhibited potent antibacterial activity against Escherichia coli strain. Compounds 7d, 7f, 7g, 7k, 7l , and 7m showed potent antibacterial activity against all bacterial strains. Compounds 7a, 7g, 7h, 7k, 7l , and 7m exhibited potent antifungal activity against all fungal strains. Furthermore, a molecular docking study revealed that compounds 7d, 7f, 7g , and 7k could bind to the active site of E. coli DNA gyrase subunit B protein and form hydrogen bonding with crucial amino acid residues Arg136 in the active sites. Comprehensively, our study recommends that 7d, 7f, 7g , and 7k could be a promising lead for developing more efficient antimicrobial drug candidates and DNA gyrase inhibitors. 相似文献
988.
989.
It is well reported that the environmental factors along with different endocrine stimulus play a crucial role in maintenance of adrenocortical activity in birds. This study is first to report a detailed seasonal activity cycle of adrenal cortex, particu-larly its secretory physiology in a tropical nocturnal bird, Indian spotted owlet Athene brama . The maximum cortical activity having highest glandular mass, glandular free cholesterol, esterified cholesterol profiles, and peak level of corticosterone in plasma coincided with the long day length, highest temperature and increasing amplitude of relative humidity and rainfall of the early summer month, May. Cortical activity declined to minimum level in August when the ecofactors also declined parallely and hence, the birds entered into partial hibernation. The cortical activity progressed slowly throughout the winter (September-March) to reach maximum level in May. Further, the electron microscopic observations of cortical cell morphology strongly supported the above seasonal activity status of the gland revealing a comparatively large number of mitochondria during May than August, along with lipid filled vacuoles during May but not in August. Besides, assessment of gonadal and pineal hormones in relation with seasonal activity of adrenal cortex presented a parallel relationship with gonad while completely inverse relationship with pineal. Therefore, the study concludes that the seasonal adrenocortical activity of this tropical nocturnal bird might be regulated by multiple factors, particularly by the environmental temperature, humidity/rainfall and photoperiod along with the internal factors at least by gonadal and pineal hormones. 相似文献
990.
Kumari Kamalesh Nadav Scher Tom Biton Eyal D. Schejter Ben-Zion Shilo Ori Avinoam 《Developmental cell》2021,56(11):1603-1616.e6
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