687 research outputs found
Accurate inspiral-merger-ringdown gravitational waveforms for non-spinning black-hole binaries including the effect of subdominant modes
We present an analytical waveform family describing gravitational waves (GWs)
from the inspiral, merger and ringdown of non-spinning black-hole binaries
including the effect of several non-quadrupole modes [( apart from ].
We first construct spin-weighted spherical harmonics modes of hybrid waveforms
by matching numerical-relativity simulations (with mass ratio )
describing the late inspiral, merger and ringdown of the binary with
post-Newtonian/effective-one-body waveforms describing the early inspiral. An
analytical waveform family is constructed in frequency domain by modeling the
Fourier transform of the hybrid waveforms making use of analytical functions
inspired by perturbative calculations. The resulting highly accurate,
ready-to-use waveforms are highly faithful (unfaithfulness ) for observation of GWs from non-spinning black hole binaries and are
extremely inexpensive to generate.Comment: 10 pages, 5 figure
Testing the no-hair nature of binary black holes using the consistency of multipolar gravitational radiation
Gravitational-wave (GW) observations of binary black holes offer the best probes of the relativistic, strong-field regime of gravity. Gravitational radiation in the leading order is quadrupolar. However, nonquadrupole (higher order) modes make appreciable contribution to the radiation from binary black holes with large mass ratios and misaligned spins. The multipolar structure of the radiation is fully determined by the intrinsic parameters (masses and spin angular momenta of the companion black holes) of a binary in quasicircular orbit. Following our previous work [S. Dhanpal, A. Ghosh, A. K. Mehta, P. Ajith, and B. S. Sathyaprakash, Phys. Rev. D 99, 104056 (2019).], we develop multiple ways of testing the consistency of the observed GW signal with the expected multipolar structure of radiation from binary black holes in general relativity. We call this a no-hair test of binary black holes as this is similar to testing the no-hair theorem for isolated black holes through mutual consistency of the quasinormal mode spectrum. We use Bayesian inference on simulated GW signals that are consistent/inconsistent with binary black holes in general relativity to demonstrate the power of the proposed tests. We also make estimate systematic errors arising as a result of neglecting companion spins
Review: Mycoendophytes in medicinal plants: Diversity and bioactivities
Rai M, Gade A, Rathod D, Dar M, Varma A. 2012. Review: Mycoendophytes in medicinal plants: Diversity and bioactivities. Nusantara Bioscience 4: 86-96. Endophytes are microorganisms that reside in internal tissues of living plants without causing any negative effect. These offer tremendous potential for the exploitation of novel and eco-friendly secondary metabolites used in medicine, the pharmaceutical industry and agriculture. The present review is focused on diversity of endophytes, current national and international bioactive secondary metabolite scenario and future prospects. Endophytic fungi as novel source of potentially useful medicinal compounds are discussed along with the need to search for new and more effective agents from endophytes to combat disease problems
Characterization of Actinomycetes and Trichoderma spp. for cellulase production utilizing crude substrates by response surface methodology
Laboratory bench scaling was done and an average of 1.85 fold increase by Response Surface Methodology (RSM) optimization was obtained. It was found that the predicted value (4.96 IU/ml) obtained by RSM is in close accordance with observed activity 5.14 IU/ml. Endoglucanases are mainly induced by CMC while Wheat bran (natural substrate) exoglucanase is more active when induced by avicel and cellulose. Addition of substrate beyond a level caused inhibition of cellulase production. The molecular weight of protein as determined by SDS-PAGE is very similar to molecular weight of cellulase of Trichoderma viride (T. viride) cellulase and Trichoderma reesei (T. reesei) endoglucanase. T. reesei β-glucosidase has high enzymatic activity on CMC substrate when compared with T. viride β-glucosidase. Secondary structure analysed by using Circular Dichroism confirmed that composition of celluase system is very similar to other analysed species. The cellulase was found to be active in pH range of 4.8-5.5; while temperature range varied from 50°C to 70°C. Although the enzymatic activity produced by mutants were lesser than the parent, but in one case mutants of Trichoderma reesei’s BGL has shown higher activity on cellulose
Formulation And Development Of Transdermal Patch Of Amlodipine Besylate Using Novel Polymers As Rate Controlling Membrane
This research study aims to formulate, prepare and evaluate transdermal drug delivery system for the purpose of controlled release of Amlodipine Bebesylate as a model drug using different polymers as a rate controlling membraneamlodipine undergoes first pass metabolism and also has easy permeability through skin therefore transdermal system of Amlodipine Bebesylate can be developed. The transdermal patches for the delivery were prepared by evaporation method i.e., solvent evaporation method. A matrix-type amlodipine besylate transdermal drug delivery system was prepared using novel polymers such as hydroxypropyl methylcellulose (HPMC) and sodium carboxymethylcellulose (SCMC) and Carbopol P 934 as a rate controlling or rate limiting membrane which delivers the drug or releases the therapeutic drugin controlled and a predetermined manner and rate. The formula for the transdermal patch was optimized using the experimental design. On the basis of the Data from drug release studies and the drug content the optimized batch was found to be F14 showing 80.1% of drug release and 95.62% of drug content. The patches were also evaluated forvarious evaluation parameters such as thickness uniformity,weight variation, moisture content determination, hygroscopicity &tensile strength
Effect of Light Quality on Phycobilisome Components of the Cyanobacterium Spirulina platensis
Biofilm Producing Clinical \u3ci\u3eStaphylococcus aureus\u3c/i\u3e Isoates Augmented Prevalence of Antibiotic Resistant Cases In Tertiary Care Hospitals of Nepal
Staphylococcus aureus, a notorious human pathogen, is a major cause of the community as well as healthcare associated infections. It can cause a diversity of recalcitrant infections mainly due to the acquisition of resistance to multiple drugs, its diverse range of virulence factors, and the ability to produce biofilm in indwelling medical devices. Such biofilm associated chronic infections often lead to increase in morbidity and mortality posing a high socio-economic burden, especially in developing countries. Since biofilm formation and antibiotic resistance function dependent on each other, detection of biofilm expression in clinical isolates would be advantageous in treatment decision. In this premise, we attempt to investigate the biofilm formation and its association with antibiotic resistance in clinical isolates from the patients visiting tertiary health care hospitals in Nepal. Bacterial cells isolated from clinical samples identified as S. aureus were examined for in-vitro biofilm production using both phenotypic and genotypic assays. The S. aureus isolates were also examined for susceptibility patterns of clinically relevant antibiotics as well as inducible clindamycin resistance using standard microbiological techniques and D-test, respectively. Among 161 S. aureus isolates, 131 (81.4%) were methicillin resistant S. aureus (MRSA) and 30 (18.6%) were methicillin sensitive S. aureus (MSSA) strains. Although a majority of MRSA strains (69.6%) showed inducible clindamycin resistance, almost all isolates (97% and 94%) were sensitive toward chloramphenicol and tetracycline, respectively. Detection of in vitro production of biofilm revealed the association of biofilm with methicillin as well as inducible clindamycin resistance among the clinical S. aureus isolates
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