2,104 research outputs found
A reddening-free method to estimate the Ni mass of Type Ia supernovae
The increase in the number of Type Ia supernovae (SNe\,Ia) has demonstrated
that the population shows larger diversity than has been assumed in the past.
The reasons (e.g. parent population, explosion mechanism) for this diversity
remain largely unknown. We have investigated a sample of SNe\,Ia near-infrared
light curves and have correlated the phase of the second maximum with the
bolometric peak luminosity. The peak bolometric luminosity is related to the
time of the second maximum (relative to the {\it B} light curve maximum) as
follows : .
Ni masses can be derived from the peak luminosity based on Arnett's
rule, which states that the luminosity at maximum is equal to instantaneous
energy generated by the nickel decay. We check this assumption against recent
radiative-transfer calculations of Chandrasekhar-mass delayed detonation models
and find this assumption is valid to within 10\% in recent radiative-transfer
calculations of Chandrasekhar-mass delayed detonation models.
The vs. relation is applied to a sample of 40 additional
SNe\,Ia with significant reddening ( 0.1 mag) and a reddening-free
bolometric luminosity function of SNe~Ia is established. The method is tested
with the Ni mass measurement from the direct observation of
rays in the heavily absorbed SN 2014J and found to be fully
consistent.
Super-Chandrasekhar-mass explosions, in particular SN\,2007if, do not follow
the relations between peak luminosity and second IR maximum. This may point to
an additional energy source contributing at maximum light.
The luminosity function of SNe\,Ia is constructed and is shown to be
asymmetric with a tail of low-luminosity objects and a rather sharp
high-luminosity cutoff, although it might be influenced by selection effects.Comment: 9 pages, 3 figures, Accepted to A&
Experimental and Clinical Evaluation of Nootropic Activity of Bacopa monniera Linn. (Brahmi)
Bacopa monniera Linn. (Brahmi) is an annual creeper belonging to familyScrophulariaceae and growing all over the Indian sub-continent in marshy areas. It is a major Medhya Rasayana used in Ayurveda for treatment of memory disorders. Large number of saponins and glycosides has been isolated from the plant. Most of the experimental and clinical studies have been done with crude extracts or standardized preparation of the two active saponins Bacosides A and B.Extracts or saponin mixture facilitate learning, improve consolidation of learned behavior and delay extinction in several models of learnt behavior in normal rats and mice as well as in chemically induced or transgenic models of Alzheimer's disease. They also prevent or reverse amnesia produced by drugs, stress or ischemic hypoxia. Other CNS effects include anti-anxiety, anti-convulsant and analgesic activity. Several mechanisms have been proposed to explain the mechanism of these CNS effects.Extracts as well as the bacoside preparation have been found safe and well tolerated in healthy volunteers in single dose or chronic administration for several weeks in a number of double blind placebo controlled studies in India and abroad. Chronic administration significantly improved information processing, learning and memory consolidation. It was found more effective than caffeine in a comparative study.Double blind placebo controlled studies with bacoside preparation have demonstrated beneficial effects and safety in elderly patients with Age Related Memory Impairment and in children with Attention Deficit Memory Disorder. It has also been found useful in anxiety neurosis, epilepsy and sleep disturbances in post menopausal women.The standardized preparation is marketed as a prescription drug after having obtained the necessary regulatory approval in India, Australia, New Zealand and South Africa and as an OTC product in several other south east Asian and African countries.Bacopa monniera Linn. (Brahmi) is an annual creeper belonging to familyScrophulariaceae and growing all over the Indian sub-continent in marshy areas. It is amajor Medhya Rasayana used in Ayurveda for treatment of memory disorders. Largenumber of saponins and glycosides has been isolated from the plant. Most of theexperimental and clinical studies have been done with crude extracts or standardizedpreparation of the two active saponins Bacosides A and B.Extracts or saponin mixture facilitate learning, improve consolidation of learnedbehavior and delay extinction in several models of learnt behavior in normal rats andmice as well as in chemically induced or transgenic models of Alzheimer's disease.They also prevent or reverse amnesia produced by drugs, stress or ischemic hypoxia.Other CNS effects include anti-anxiety, anti-convulsant and analgesic activity. Severalmechanisms have been proposed to explain the mechanism of these CNS effects.Extracts as well as the bacoside preparation have been found safe and well tolerated inhealthy volunteers in single dose or chronic administration for several weeks in anumber of double blind placebo controlled studies in India and abroad. Chronicadministration significantly improved information processing, learning and memoryconsolidation. It was found more effective than caffeine in a comparative study.Double blind placebo controlled studies with bacoside preparation have demonstratedbeneficial effects and safety in elderly patients with Age Related Memory Impairmentand in children with Attention Deficit Memory Disorder. It has also been found usefulin anxiety neurosis, epilepsy and sleep disturbances in post menopausal women.The standardized preparation is marketed as a prescription drug after having obtainedthe necessary regulatory approval in India, Australia, New Zealand and South Africaand as an OTC product in several other south east Asian and African countries.Bacopa monniera Linn. (Brahmi) is an annual creeper belonging to familyScrophulariaceae and growing all over the Indian sub-continent in marshy areas. It is a major Medhya Rasayana used in Ayurveda for treatment of memory disorders. Large number of saponins and glycosides has been isolated from the plant. Most of the experimental and clinical studies have been done with crude extracts or standardized preparation of the two active saponins Bacosides A and B.Extracts or saponin mixture facilitate learning, improve consolidation of learned behavior and delay extinction in several models of learnt behavior in normal rats and mice as well as in chemically induced or transgenic models of Alzheimer's disease. They also prevent or reverse amnesia produced by drugs, stress or ischemic hypoxia. Other CNS effects include anti-anxiety, anti-convulsant and analgesic activity. Several mechanisms have been proposed to explain the mechanism of these CNS effects.Extracts as well as the bacoside preparation have been found safe and well tolerated in healthy volunteers in single dose or chronic administration for several weeks in a number of double blind placebo controlled studies in India and abroad. Chronic administration significantly improved information processing, learning and memory consolidation. It was found more effective than caffeine in a comparative study.Double blind placebo controlled studies with bacoside preparation have demonstrated beneficial effects and safety in elderly patients with Age Related Memory Impairment and in children with Attention Deficit Memory Disorder. It has also been found useful in anxiety neurosis, epilepsy and sleep disturbances in post menopausal women.The standardized preparation is marketed as a prescription drug after having obtained the necessary regulatory approval in India, Australia, New Zealand and South Africa and as an OTC product in several other south east Asian and African countries.Bacopa monniera Linn. (Brahmi) is an annual creeper belonging to familyScrophulariaceae and growing all over the Indian sub-continent in marshy areas. It is amajor Medhya Rasayana used in Ayurveda for treatment of memory disorders. Largenumber of saponins and glycosides has been isolated from the plant. Most of theexperimental and clinical studies have been done with crude extracts or standardizedpreparation of the two active saponins Bacosides A and B.Extracts or saponin mixture facilitate learning, improve consolidation of learnedbehavior and delay extinction in several models of learnt behavior in normal rats andmice as well as in chemically induced or transgenic models of Alzheimer's disease.They also prevent or reverse amnesia produced by drugs, stress or ischemic hypoxia.Other CNS effects include anti-anxiety, anti-convulsant and analgesic activity. Severalmechanisms have been proposed to explain the mechanism of these CNS effects.Extracts as well as the bacoside preparation have been found safe and well tolerated inhealthy volunteers in single dose or chronic administration for several weeks in anumber of double blind placebo controlled studies in India and abroad. Chronicadministration significantly improved information processing, learning and memoryconsolidation. It was found more effective than caffeine in a comparative study.Double blind placebo controlled studies with bacoside preparation have demonstratedbeneficial effects and safety in elderly patients with Age Related Memory Impairmentand in children with Attention Deficit Memory Disorder. It has also been found usefulin anxiety neurosis, epilepsy and sleep disturbances in post menopausal women.The standardized preparation is marketed as a prescription drug after having obtainedthe necessary regulatory approval in India, Australia, New Zealand and South Africaand as an OTC product in several other south east Asian and African countries
Deep Learning Research: Scientometric Assessment of Global Publications Output during 2004 -17
The paper provides a quantitative and qualitative description of deep learning research using bibliometric indicators covering global research publications published during 14-year period 2004-17. Global deep learning research registered 106.76% high growth per annum, and averaged 7.99 citations per paper. Top 10 countries world- over dominate the research field with their 99.74% global publications share and more than 100% global citations share. China ranks the top with the highest (29.25%) global publications share, followed by USA (26.46%), U.K. (6.40%), etc. during the period. Canada tops in relative citation index (5.30). International collaboration has been a major driver of research in the subject with 14.96% to 53.76% of national-level share of top 10 countries output appeared as international collaborative publications. Computer Science is one of the most popular areas of research in deep learning research (76.85% share). The study identifies top 50 most productive organizations and 50 most productive authors and top 20 most productive journals reporting deep learning research and 118 highly cited papers with 100+ citations per paper
Claudin Family of Proteins and Cancer: An Overview
Tight junctions are the apical cell-cell adhesion that regulate paracellular permeability and are critical for epithelial cell polarity. Molecular architecture of tight junction has been studied extensively, which has confirmed that claudin family of proteins is integral component of tight junction. Loss of cell-cell adhesion is central to the cellular transformation and acquisition of metastatic potential; however, the role of claudin family of proteins play in a series of pathophysiological events, including human carcinoma development, is only now beginning to be understood. Several claudin mouse knockout models have been generated and the diversity of phenotypes observed clearly demonstrates their important roles in the maintenance of tissue integrity in various organs and suggest that claudins also participate in cellular contexts other than tight junctions. The mechanisms of claudin regulation and their exact roles in normal physiology and disease are being elucidated, but much work remains to be done. In this review, we have discussed the conceptual framework concerning claudins and their potential implication in cancer. We predict that next several years will likely witness a boom in our understanding of the potential role of claudins in the regulation of tumorigenesis, which may, in turn, provide new approaches for the targeted therapy
Nebular spectroscopy of SN 2014J: Detection of stable nickel in near infrared spectra
We present near infrared (NIR) spectroscopy of the nearby supernova 2014J
obtained 450 d after explosion. We detect the [Ni II] 1.939 m line
in the spectra indicating the presence of stable Ni in the ejecta. The
stable nickel is not centrally concentrated but rather distributed as the iron.
The spectra are dominated by forbidden [Fe II] and [Co II] lines. We use lines,
in the NIR spectra, arising from the same upper energy levels to place
constraints on the extinction from host galaxy dust. We find that that our data
are in agreement with the high and low found in earlier studies
from data near maximum light. Using a Ni mass prior from near maximum
light -ray observations, we find 0.05 M of stable nickel
to be present in the ejecta. We find that the iron group features are
redshifted from the host galaxy rest frame by 600 km s.Comment: 6 pages, 4 figures, submitted to A&
Emergence of metronidazole-resistant Bacteroides fragilis, India.
This article does not have an abstract
Mobile computing: a scientometric assessment of global publications output
The paper examines 34641 global publications output on mobile computing research, as covered in Scopus database during 2007-16. The study finds that mobile computing research is growing at 9.35% rate per annum and its citation impact averaged to 3.39 citations per paper. The global share of top 10 most productive countries ranged from 3.29% to 31.06%, with largest global publication share coming from China (31.06%), followed by USA (15.35%), etc. Together, the top 10 most productive countries accounted for 81.24% global publication share during 2007-16. Seven of top 10 countries achieved relative citation index above world average of 1: USA (2.37), U.K. (1.78), Italy (1.72), Canada (1.64), etc. International collaborative publications share of top 10 most productive countries in mobile computing research during 2007-16 varied from 11.55% to 48.16%. Computer Science, among subjects, accounted for the largest publication share (89.55%), followed by engineering (33.58%), social sciences (18.67%), mathematics (8.74%), etc. during 2007-16. The top 20 most productive organizations and authors contributed 14.79% and 1.76% global publication share respectively and accounted for 9.5% and 5.11% global citation share respectively during 2007-16. The top 20 journals accounted for 24.11% share of total journals output of 5673 papers during 2007-16. The top 50 highly cited publications registered citations in the range from 164 to 1235 citations per paper and together these top 50 papers cumulated 16822 citations, with an average of 336.4 citations per paper. These 50 highly cited papers resulted from participation of 184 authors and 103 organizations, and were published in 31 journals, including 4 in IEEE Transactions on Mobile Computing, 2 papers each in Decision Support System, IEEE Communication Magazine, IEEE Pervasive Computing and IEEE Communication Surveys & Tutorials and 1 paper each in other 26 journals.
Obesity-induces Organ and Tissue Specific Tight Junction Restructuring and Barrier Deregulation by Claudin Switching
Obesity increases susceptibility to multiple organ disorders, however, underlying mechanisms remain unclear. The subclinical inflammation assisted by obesity-induced gut permeability may underlie obesity-associated co-morbidities. Despite eminent clinical significance of the obesity led gut barrier abnormalities, its precise molecular regulation remains unclear. It is also unknown whether barrier deregulations, similar to the gut, characterize other vital organs in obese individuals. The claudin family of proteins is integral to the tight junction (TJ), the apical cell-cell adhesion and a key regulator of the epithelial barrier. Using comprehensive physiological and biochemical analysis of intestinal and renal tissues from high-fat diet fed mice, critical for maintaining metabolic homeostasis, this study demonstrates that profound TJ-restructuring by organ and tissue-specific claudin switching characterize obese organs. Protein expression and cellular distribution were examined. In-silico analysis further highlighted potential association of select claudins, modulated by the obesity, with signaling and metabolic pathways of pathological significance. In vitro studies using Leptin or DCA-treatment suggested causal significance of obesity-induced changes in tissue microenvironment in regulating barrier deregulations in tissue-specific manner. Overall, current findings advances our understanding of the molecular undertakings of obesity associated changes that help predispose to specific diseases and also identifies novel windows of preventive and/or therapeutic interventions
- …