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241.
Rajat Bajaj Pooja Rohilla Aman Prasad Ravita Ankur Shandilya Allam Srinivasa Rao 《Luminescence》2023,38(4):428-436
Samarium ion (Sm3+)-doped alkali zinc alumino borosilicate (AZABS) glass was synthesized via quick melt quench technique. Various spectroscopic studies like optical absorption, photoluminescence (PL) emission, PL excitation, temperature-dependent PL and PL decay kinetics were performed on the as prepared glass system. Under 402 nm excitation, three sharp bands at wavelengths 563, 599 and 645 nm corresponding to transitions 4G5/2 → 6H5/2, 6H7/2 and 6H9/2, respectively, can be seen in the PL emission spectra. The 0.25 mol% Sm3+ glass has the highest intensity for these emissions. The lanthanide interaction in the glass matrix is dipole–dipole in nature as was proven from Dexter's analysis. The direct bandgap of 0.25 mol% Sm3+-doped AZABS glass was calculated to be 2.88 eV. The lifetimes of the as prepared glass range from 1.93 ms for the lowest concentration of Sm3+ to 0.75 ms for the highest. From temperature dependent PL studies, the activation energy for 0.25 mol% Sm3+-doped AZABS glass was found to be 0.19 eV which shows high thermal stability of this glass. We propose to utilize these Sm3+-doped AZABS glasses for white-light emitting diodes (w-LEDs) and solid-state lighting (SSL) applications. 相似文献
242.
Xanthomonas axonopodis pv. citri (Xac) is the causal agent of citrus bacterial canker (CBC) and is a serious problem worldwide. Like CBC, several important diseases in other fruits, such as mango, pomegranate, and grape, are also caused by Xanthomonas pathovars that display remarkable specificity toward their hosts. While citrus and mango diseases were documented more than 100 years ago, the pomegranate and grape diseases have been known only since the 1950s and 1970s, respectively. Interestingly, diseases caused by all these pathovars were noted first in India. Our genome-based phylogenetic studies suggest that these diverse pathogens belong to a single species and these pathovars may be just a group of rapidly evolving strains. Furthermore, the recently reported pathovars, such as those infecting grape and pomegranate, form independent clonal lineages, while the citrus and mango pathovars that have been known for a long time form one clonal lineage. Such an understanding of their phylogenomic relationship has further allowed us to understand major and unique variations in the lineages that give rise to these pathovars. Whole-genome sequencing studies including ecological relatives from their putative country of origin has allowed us to understand the evolutionary history of Xac and other pathovars that infect fruits. 相似文献
243.
AbstractHuman meprin-β, a zinc metalloprotease belonging to the astacin family, have been found to be associated with many pathological conditions like inflammatory bowel disease, fibrosis and neurodegenerative disease. The inhibition of meprin-β by various inhibitors, both macromolecular and small molecules, is crucial in the control of several diseases. Human fetuin-A, a negative acute phase protein involved in inflammatory disease, has recently been identified as an endogenous inhibitor for meprin-β. In this computational study, an integrated in silico approach was performed using existing structural information of meprin-β coupled with ab initio modelling of human fetuin-A to predict a rational model of the complex through protein–protein docking. Further, the models were optimized and validated to generate an ensemble of conformations through extensive molecular dynamics simulation. Virtual alanine scanning mutagenesis was explored to identify hotspot residues on both proteins significant for protein–protein interaction (PPI). The results of the study provide structural insight into PPI between meprin-β and fetuin-A which can be useful in designing molecules to modulate meprin-β activity. Communicated by Ramaswamy H. Sarma 相似文献
244.
Previously, DAG scheduling schemes used the mean (average) of computation or communication time in dealing with temporal heterogeneity.
However, it is not optimal to consider only the means of computation and communication times in DAG scheduling on a temporally
(and spatially) heterogeneous distributed computing system. In this paper, it is proposed that the second order moments of
computation and communication times, such as the standard deviations, be taken into account in addition to their means, in
scheduling “stochastic” DAGs. An effective scheduling approach which accurately estimates the earliest start time of each
node and derives a schedule leading to a shorter average parallel execution time has been developed. Through an extensive
computer simulation, it has been shown that a significant improvement (reduction) in the average parallel execution times
of stochastic DAGs can be achieved by the proposed approach. 相似文献
245.
S D Roy E M Hawes G McKay J W Hubbard K K Midha 《Canadian journal of physiology and pharmacology》1985,63(7):778-781
The metabolism of the beta 2-adrenoceptor agent methoxyphenamine was investigated in rats of the Lewis and Dark Agouti strains, which are proposed models for human extensive and poor metabolizers of debrisoquine, respectively. Following oral ingestion of 20 mg kg-1 of methoxyphenamine, Dark Agouti excreted, on the average, significantly more methoxyphenamine and less O-demethylmethoxyphenamine and 5-hydroxymethoxyphenamine in 0- to 24-h urine than Lewis. In contrast, the N-demethylation of methoxyphenamine showed no interphenotype differences between the two strains. It is possible that in rats, the form of cytochrome P-450, which controls the 4-hydroxylation of debrisoquine, may also control the O-demethylation and aromatic 5-hydroxylation of methoxyphenamine. 相似文献
246.
Sourabh Agstam Ashutosh Yadav Praveen Kumar-M Ankur Gupta 《Indian pacing and electrophysiology journal》2021,21(1):36-43
BackgroundAmong many drugs that hold potential in COVID-19 pandemic, chloroquine (CQ), and its derivative hydroxychloroquine (HCQ) have generated unusual interest. With increasing usage, there has been growing concern about the prolongation of QTc interval and Torsades de Pointes (TdP) with HCQ, especially in combination with azithromycin.AimsThis meta-analysis is planned to study the risk of QTc prolongation and Torsades de pointes (TdP) by a well-defined criterion for HCQ, CQ alone, and in combination with Azithromycin in patients with COVID-19.MethodsA comprehensive literature search was made in two databases (PubMed, Embase). Three outcomes explored in the included studies were frequency of QTc > 500 ms (ms) or ΔQTc > 60 ms (Outcome 1), frequency of QTc > 500 ms (Outcome 2) and frequency of TdP (Outcome 3). Random effects method with inverse variance approach was used for computation of pooled summary and risk ratio.ResultsA total of 13 studies comprising of 2138 patients were included in the final analysis. The pooled prevalence of outcome 1, outcome 2 and outcome 3 for HCQ, CQ with or without Azithromycin were 10.18% (5.59–17.82%, I2 – 92%), 10.22% (6.01–16.85%, I2 – 79%), and 0.72% (0.34–1.51, I2 – 0%) respectively. The prevalence of outcome 2 in subgroup analysis for HCQ and HCQ + Azithromycin was 7.25% (3.22–15.52, I2 – 59%) and 8.61% (4.52–15.79, I2 – 76%), respectively. The risk ratio (RR) for outcome 1 and outcome 2 between HCQ + Azithromycin and HCQ was 1.22 (0.77–1.93, I2 – 0%) & 1.51 (0.79–2.87, I2 – 13%), respectively and was not significant. Heterogeneity was noted statistically as well clinically (regimen types, patient numbers, study design, and outcome definition).ConclusionThe use of HCQ/CQ is associated with a high prevalence of QTc prolongation. However, it is not associated with a high risk of TdP. 相似文献
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Singh Ankur Roychoudhury Aryadeep Samanta Santanu Banerjee Aditya 《Journal of Plant Growth Regulation》2021,40(4):1579-1593
Journal of Plant Growth Regulation - The aim of the current study was to investigate the regulation of tricarboxylic acid (TCA) cycle and sugar metabolism in the seedlings of the rice variety,... 相似文献