1,320 research outputs found

    New mixed ligand complexes of ruthenium(II) that incorporate a modified phenanthroline ligand: synthesis, spectral characterization and DNA binding

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    The hexafluorophosphate and chloride salts of two ruthenium(II) complexes, viz. [Ru(phen)(ptzo)2]2 and [Ru(ptzo)3]2+, where ptzo = 1,10-phenanthrolino[5,6-e]1,2,4-triazine-3-one (ptzo) - a new modified phenanthroline (phen) ligand, have been synthesised. These complexes have been characterised by infrared, UV-Vis, steady-state emission and1H NMR spectroscopic methods. Results of absorption and fluorescence titration as well as thermal denaturation studies reveal that both thebis- and tris-complexes of ptzo show moderately strong affinity for binding with calf thymus (CT) DNA with the binding constants being close to 105M-1 in each case. An intercalative mode of DNA binding has been suggested for both the complexes. Emission studies carried out in non-aqueous solvents and in aqueous media without DNA reveal that both [Ru(phen)(ptzo)2]2+ and [Ru(ptzo)3]2+ are weakly luminescent under these solution conditions. Successive addition of CT DNA to buffered aqueous solutions containing [Ru(phen)(ptzo)2]2+results in an enhancement of the emission. These results have been discussed in the light of the dependence of the structure-specific deactivation processes of the MLCT state of the metallo-intercalator with the characteristic features of its DNA interaction. In doing so, attempts have been made to compare and contrast its properties with those of the analogous phenanthroline-based complexes including the ones reported by us previously

    OPTIMIZATION AND CHARECTERIZATION OFINTRACELLULAR ORANGE FLUORESCENT PIGMENT FROM BACILLUS ENDOPHYTICUS (AVP-9(Kf527823)

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    Objective: Our study aimed to characterize and optimize the physico-chemical properties which render the high yield of intracellular orange fluorescent pigment (IOFP) and its antibacterial activity against clinical pathogens.Methods: Intracellular orange fluorescent pigment (IOFP) extracted from Bacillus endophyticus AVP-9(Kf527823) a rhizobacteria of chilli agricultural field using different solvent systems, fractioned by TLC and analyzed for absorption maxima. Purified pigment was screened for antimicrobial activity against clinical pathogen, Optimization of cultural conditions for maximizing the yield of pigment and compared the yield in different broth media.Results: AVP-9(Kf527823) showed circular, large orange color colonies which fluoresced orange under U. V light,. Intracellular pigment affectively extracted in acetone showed a bright fluorescent orange spot on the TLC plate, and absorption maxima at 493 nm. Antibacterial activity of isolated pigment showed highest zone of inhibition against E. coli and least to Pseudomonas. Maximum yield of the pigment was achieved in modified nutrient brot (MNB)h medium containing 2% w/v nutrient broth containing1% w/v glucose,1% w/v peptone and0.5% methionine at 35 °C and pH 7.0 with 48 h of incubation period. The yield was observed maximum in MNB. Compared to lactose broth, Tryptone soya broth and peptone water.Conclusion: Bright fluorescent orange pigment of Bacterium avp-9(Kf527823) with absorption maxima at 493 indicating that the pigment shows the characters of carotenoids. Yield maximum in MNB and its potential antibacterial activity needs further investigation for pharmaceutical applications

    Real-Gas Effects and Phase Separation in Underexpanded Jets at Engine-Relevant Conditions

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    A numerical framework implemented in the open-source tool OpenFOAM is presented in this work combining a hybrid, pressure-based solver with a vapor-liquid equilibrium model based on the cubic equation of state. This framework is used in the present work to investigate underexpanded jets at engine-relevant conditions where real-gas effects and mixture induced phase separation are probable to occur. A thorough validation and discussion of the applied vapor-liquid equilibrium model is conducted by means of general thermodynamic relations and measurement data available in the literature. Engine-relevant simulation cases for two different fuels were defined. Analyses of the flow field show that the used fuel has a first order effect on the occurrence of phase separation. In the case of phase separation two different effects could be revealed causing the single-phase instability, namely the strong expansion and the mixing of the fuel with the chamber gas. A comparison of single-phase and two-phase jets disclosed that the phase separation leads to a completely different penetration depth in contrast to single-phase injection and therefore commonly used analytical approaches fail to predict the penetration depth.Comment: Preprint submitted to AIAA Scitech 2018, Kissimmee, Florid

    Stochastic Budget Optimization in Internet Advertising

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    Internet advertising is a sophisticated game in which the many advertisers "play" to optimize their return on investment. There are many "targets" for the advertisements, and each "target" has a collection of games with a potentially different set of players involved. In this paper, we study the problem of how advertisers allocate their budget across these "targets". In particular, we focus on formulating their best response strategy as an optimization problem. Advertisers have a set of keywords ("targets") and some stochastic information about the future, namely a probability distribution over scenarios of cost vs click combinations. This summarizes the potential states of the world assuming that the strategies of other players are fixed. Then, the best response can be abstracted as stochastic budget optimization problems to figure out how to spread a given budget across these keywords to maximize the expected number of clicks. We present the first known non-trivial poly-logarithmic approximation for these problems as well as the first known hardness results of getting better than logarithmic approximation ratios in the various parameters involved. We also identify several special cases of these problems of practical interest, such as with fixed number of scenarios or with polynomial-sized parameters related to cost, which are solvable either in polynomial time or with improved approximation ratios. Stochastic budget optimization with scenarios has sophisticated technical structure. Our approximation and hardness results come from relating these problems to a special type of (0/1, bipartite) quadratic programs inherent in them. Our research answers some open problems raised by the authors in (Stochastic Models for Budget Optimization in Search-Based Advertising, Algorithmica, 58 (4), 1022-1044, 2010).Comment: FINAL versio

    Kloniranje, ekspresija i karakterizacija paraflagelarnog gena Rod 2 bičaša Trypanosoma evansi

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    Paraflagellar rod is the major structural component of the trypanosomatid flagellum and is identified as a complex lattice of filaments which runs parallel to the axoneme throughout most of the flagellar length. The present study was carried out to investigate the existence of the paraflagellar rod (PFR 2) gene in Trypanosoma evansi infecting Indian cattle. Local isolates of T. evansi collected from naturally infected cow were multiplied in Wistar rats. Complementary DNA (cDNA) was synthesized from the RNA of host cell free T. evansi parasites by reverse transcription. The gel purified PCR product (PFR 2 gene of T. evansi) was cloned into the pTZ57R/T vector system. The nucleotide sequence of the PFR 2 gene of the T. evansi S.V.V.U. isolate (Accession No. KT277497) obtained in the present study revealed 100% homology with T. evansi China isolate and 99% homology with T. evansi Izatnagar and Bikaner isolates. The recombinant protein was sub-cloned into pET 32a and expressed in the BL21 (DE3) pLysS expression system. The PFR 2 gene of T. evansi S.V.V.U. isolate was further characterized by determination of its protein profile with SDS-PAGE and western blotting. Indirect ELISA was optimized for detection of the specific antibody titre against the recombinant protein of the PFR 2 gene of T. evansi. In the kinetoplastid species the PFR 2 gene is highly conserved. Therefore the PFR 2 gene was suggested as a vaccine candidate, as well as a diagnostic antigen.Paraflagelarni štapić glavna je strukturna komponenta tripanosomskog biča i dio je kompleksa filamenaza koji teku paralelno s aksonemom duž biča. Istraživanje je provedeno kako bi se ispitalo postojanje paraflagelarnog gena Rod 2 (PFR2) u bičaša Trypanosoma evansi koji invadira goveda u Indiji. Lokalni izolat T. evansi prikupljen od prirodno invadiranih krava umnožen je u Wistar štakora. Komplementarna DNA (cDNA) sintetizirana je iz RNA obrnutom transkripcijom iz stanica neinvadiranih nositelja T. evansi parazita. Pročišćeni PCR produkt (gen PFR2 bičaša T. evansi) kloniran je u vektorski sustav pTZ57R/T. Nukleotidna sekvencija gena PFR2 bičaša T. evansi, izolat S.V.V.U. (pristupni broj KT277497) dobivena u ovom istraživanju pokazala je 100 %-tnu sličnost s izolatom T. evansi China i 99 %-tnu s izolatom T. evansi Izatnagar i Bikaner. Rekombinantni protein ponovno je kloniran u sustavu pET 32a i prikazan u sustavu BL21 (DE3) pLysS. Gen PFR2 bičaša T. evansi, izolat S.V.V.U. dalje je karakteriziran određivanjem proteinskog profila metodama SDS-PAGE i Western blotting. Indirektni test ELISA optimiziran je za dokaz titra specifičnih protutijela za rekombinantni protein gena PFR2 bičaša T. evansi. U kinetoplastida gen PFR2 izrazito je očuvan. Stoga bi se gen PFR2 mogao upotrijebiti za cjepivo te kao dijagnostički antigen

    Heat content of the Arabian Sea Mini Warm Pool is increasing

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    © The Author(s), 2015. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Atmospheric Science Letters 17 (2016): 39-42, doi:10.1002/asl.596.Sea surface temperature in the Arabian Sea Mini Warm Pool has been suggested to be one of the factors that affects the Indian summer monsoon. In this paper, we analyze the annual ocean heat content (OHC) of this region during 1993–2010, using in situ data, satellite observations, and a model simulation. We find that OHC increases significantly in the region during this period relative to the north Indian Ocean, and propose that this increase could have caused the decrease in Indian Summer Monsoon Rainfall that occurred at the same time

    Classification of Ultra Fine Particles from Fly Ash

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    The annual generation of coal combustion residue in the country is 110 MT. The generation of coal combustion residue is expected to increase with ever increasing demand for power. Management of this solid waste has been a great concern to the nation. Most of the reports on utilization of coal combustion residue are limited to direct usage of the material or selective collection from ESP fields in the thermal power plants. In this connection several efforts are being made in the country to enhance its application as a replacement to cement, soil modifier, roads and embankments etc. Very little or no research attempts are made in understanding the appropriate compo-nents which results in beneficial properties and value added products. Fly ash in very fine size range exhibits spherical morphological characteristics and thus acts as good fillers in rubber and polymer compounds. However, recovery of this size material from the bulk is yet a challenge in the process industry as the material forms clusters at very fine sizes. The present study is an atte-mpt to beneficiate fly ash to obtain material with an average particle size around 5 microns. A cyclone separa-tor, which employs very high g* forces for separation of particles is employed for achieving the separation. At this high g* forces, the declustering of particles is observed. This technique has generated product with an average particle size (ds& between 4 to 8 microns. The results obtained at different test runs are discussed

    Mapping and marker-assisted breeding of a gene allelic to the major Asian rice gall midge resistance gene Gm8

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    Host plant resistance is the preferred management strategy for Asian rice gall midge (Orseolia oryzae), a serious pest in many rice-growing countries. Identification of simple sequence repeat (SSR) markers that are tightly linked to pest resistance genes can accelerate development of gene pyramids for durable/multiple resistance. Based on conventional and molecular allelism tests, we report herein that rice genotype Aganni possesses Gm8 gene, conferring hypersensitive independent (HR– type) resistance to gall midge biotypes GMB1, GMB2, GMB3, GMB4, and GMB4M. The gene Gm8 was mapped to chromosome 8 within a 400-kbp region, and the SSR markers RM22685 and RM22709 flank the gene closely. Using these closely linked flanking markers, nine other gall midge-resistant genotypes were identified as carrying the same gene Gm8. Through marker-assisted selection, Gm8 has been introgressed into an elite bacterial blight-resistant cultivar, Improved Samba-Mahsuri (IS

    Discriminating neutrino mass models using Type II seesaw formula

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    In this paper we propose a kind of natural selection which can discriminate the three possible neutrino mass models, namely the degenerate, inverted hierarchical and normal hierarchical models, using the framework of Type II seesaw formula. We arrive at a conclusion that the inverted hierarchical model appears to be most favourable whereas the normal hierarchical model follows next to it. The degenerate model is found to be most unfavourable. We use the hypothesis that those neutrino mass models in which Type I seesaw term dominates over the Type II left-handed Higgs triplet term are favoured to survive in nature.Comment: No change in the results, a few references added, some changes in Type[IIB] calculation

    A holistic multi-methodology for sustainable renovation

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    A review of the barriers for building renovation has revealed a lack of methodologies, which can promote sustainability objectives and assist various stakeholders during the design stage of building renovation/retrofitting projects. The purpose of this paper is to develop a Holistic Multi-methodology for Sustainable Renovation, which aims to deal with complexity of renovation projects. It provides a framework through which to involve the different stakeholders in the design process to improve group learning and group decision-making, and hence make the building renovation design process more robust and efficient. Therefore, the paper discusses the essence of multifaceted barriers in building renovation regarding cultural changes and technological/physical changes. The outcome is a proposal for a multi-methodology framework, which is developed by introducing, evaluating and mixing methods from Soft Systems Methodologies (SSM) with Multiple Criteria Decision Making (MCDM). The potential of applying the proposed methodology in renovation projects is demonstrated through a case study
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