441 research outputs found

    Performance analysis of anomalous photocatalytic activity of Cr-doped TiO2 nanoparticles [Cr(x)TiO2(1-x)]

    Get PDF
    We report the synthesis and characterisation of pristine and chromium (Cr) metal ion-doped titanium dioxide nanoparticles [Cr(x)TiO2(1-x)] to study the anomalous effect of Cr doping on the photocatalytic property of TiO2. The presence of dopants generates more number of recombination pairs and increases surface coverage sites which decreases photocatalytic activity. We study the structural morphology of the synthesised Cr(x)TiO2(1-x) samples using X-ray diffraction (XRD) and X-ray photoelectron spectroscopy analysis. The effect of Cr3+ ions on the optical properties of TiO2 has been studied using various imaging and spectroscopic techniques. Further, the effect of doping of Cr on the photocatalytic activity of TiO2 has been analysed in detail. The concentration of Cr in TiO2 has been chosen as 0, 1, 5 and 10% by weight. It has been observed that the pristine TiO2 exhibits better photocatalytic activity as compared to Cr-doped TiO2 irrespective of the Cr concentration. This can be attributed to the fact that due to Cr doping in TiO2, the number of available adsorption sites for malachite green reduces which degrades its photocatalytic activity. It is also confirmed by photoluminescence (PL) and time-resolved photoluminescence spectroscopy. PL intensity increases, and lifetime decreases with increase in doping concentration. Radiative recombination of electron and hole pairs of Cr3+ in TiO2 degrades its photocatalytic activity. The degradation efficiency is found to be 96% in the case of pristine TiO2 which reduces to 12% when doped with x = 10% concentration of chromium. Therefore, it is observed that in comparison with Cr-doped TiO2, pristine TiO2 exhibits an improved photocatalytic activity which shows the anomalous effect of Cr doping on the photocatalytic property of TiO2

    Statistical optimization for lipase production from solid waste of vegetable oil industry

    Get PDF
    <p>The production of biofuel using thermostable bacterial lipase from hot spring bacteria out of low-cost agricultural residue olive oil cake is reported in the present paper. Using a lipase enzyme from <i>Bacillus licheniformis</i>, a 66.5% yield of methyl esters was obtained. Optimum parameters were determined, with maximum production of lipase at a pH of 8.2, temperature 50.8°C, moisture content of 55.7%, and biosurfactant content of 1.693 mg. The contour plots and 3D surface responses depict the significant interaction of pH and moisture content with biosurfactant during lipase production. Chromatographic analysis of the lipase transesterification product was methyl esters, from kitchen waste oil under optimized conditions, generated methyl palmitate, methyl stearate, methyl oleate, and methyl linoleate.</p

    Eff ect of participatory women’s groups facilitated by Accredited Social Health Activists on birth outcomes in rural eastern India: a cluster-randomised controlled trial

    Get PDF
    Background A quarter of the world’s neonatal deaths and 15% of maternal deaths happen in India. Few community-based strategies to improve maternal and newborn health have been tested through the country’s government-approved Accredited Social Health Activists (ASHAs). We aimed to test the eff ect of participatory women’s groups facilitated by ASHAs on birth outcomes, including neonatal mortality. Methods In this cluster-randomised controlled trial of a community intervention to improve maternal and newborn health, we randomly assigned (1:1) geographical clusters in rural Jharkhand and Odisha, eastern India to intervention (participatory women’s groups) or control (no women’s groups). Study participants were women of reproductive age (15–49 years) who gave birth between Sept 1, 2009, and Dec 31, 2012. In the intervention group, ASHAs supported women’s groups through a participatory learning and action meeting cycle. Groups discussed and prioritised maternal and newborn health problems, identifi ed strategies to address them, implemented the strategies, and assessed their progress. We identifi ed births, stillbirths, and neonatal deaths, and interviewed mothers 6 weeks after delivery. The primary outcome was neonatal mortality over a 2 year follow up. Analyses were by intention to treat. This trial is registered with ISRCTN, number ISRCTN31567106. Findings Between September, 2009, and December, 2012, we randomly assigned 30 clusters (estimated population 156 519) to intervention (15 clusters, estimated population n=82 702) or control (15 clusters, n=73 817). During the follow-up period (Jan 1, 2011, to Dec 31, 2012), we identifi ed 3700 births in the intervention group and 3519 in the control group. One intervention cluster was lost to follow up. The neonatal mortality rate during this period was 30 per 1000 livebirths in the intervention group and 44 per 1000 livebirths in the control group (odds ratio [OR] 0.69, 95% CI 0·53–0·89). Interpretation ASHAs can successfully reduce neonatal mortality through participatory meetings with women’s groups. This is a scalable community-based approach to improving neonatal survival in rural, underserved areas of India

    Fabrication of magnetite nanocrystals in alcohol/water mixed solvents: catalytic and colloid property evaluation

    Get PDF
    In this work, Fe3O4 nanocrystals have been synthesized by homogeneous precipitation in different alcohol/water (1 : 1) solvent mixtures at two different temperatures to elucidate the role of the dielectric constant (ε) of the reaction medium. The effects of different solvents on the catalytic activity of precipitated NPs in carbon combustion were examined. HRTEM images, SAED and XRD confirmed that the nanocrystals are of pure fcc inverse spinel Fe3O4 phase with narrow size distribution, and the crystals are completely dispersible in water. The morphological features of the nanocrystals, such as their surface termination and shape of the Fe3O4 NPs, were analyzed by HR-TEM. As ε decreases, the crystal size decreases for mono-ol systems compared to ∼13 nm size in water, whereas ethylene glycol/water yields finer ∼8.2 nm crystals although it has the highest ε among the mono-/poly-ols. A soot combustion study demonstrates that the catalytic activity is mainly due to the available surface area along with the exposure of active crystallographic facets. A study of the colloids by light scattering shows that the alcohol mediated process produces 16 to 33 nm MNP clusters composed of 2 to 3 particles in highly stable aqueous magnetic fluids. The relatively high temperature process favors higher crystallinity and particle size with reduced colloidal stability in the aqueous phase. The nanocrystalline powders and the dispersed colloids have excellent potential applications in biotechnology and selective catalysis and also as ferrofluids

    A combined microRNA-based targeted therapeutic approach to eradicate glioblastoma stem-like cells

    Get PDF
    A minor population of glioblastoma stem-like cells (GSCs) has been implicated in the relapse and resistance of glioblastoma to therapeutic treatments. Based on knowledge of the involvement of multiple microRNAs in GSC propagation, we designed a combinational approach to target the GSC population with multiple miRNA-based therapeutics. As carriers for the targeted delivery we took advantage of two aptamers that bind to, and inhibit, the receptor tyrosine kinases, Axl and PDGFRβ. We showed that the aptamer conjugates are transported through an in vitro blood-brain barrier (BBB) model. Furthermore, combining miR-137 and antimiR-10b synergizes with the receptor inhibitory function of aptamer carriers and prevents GSC expansion. Results highlighted the potential of combining multifunctional RNA-based therapeutics for selective targeting of GSCs and offer a proof of principle strategy to potentially fulfill the still unmet need for effective and safe treatment of glioma

    Effect of participatory women's groups facilitated by Accredited Social Health Activists on birth outcomes in rural eastern India: A cluster-randomised controlled trial

    Get PDF
    Background: A quarter of the world's neonatal deaths and 15% of maternal deaths happen in India. Few community-based strategies to improve maternal and newborn health have been tested through the country's government-approved Accredited Social Health Activists (ASHAs). We aimed to test the effect of participatory women's groups facilitated by ASHAs on birth outcomes, including neonatal mortality. Methods: In this cluster-randomised controlled trial of a community interve

    Dose and time-dependent tolerability and efficacy of organo-osmium complex FY26 and its tissue pharmacokinetics in hepatocarcinoma-bearing mice

    Get PDF
    The organo-osmium complex [OsII(ɳ6-p-cym)(PhAzPy-NMe2)I]+ (FY26) exhibits promising in vitro antitumour activity against mouse hepatocarcinoma Hepa1-6 and other mouse or human cancer cell lines. Here, we drastically enhance water solubility of FY26 through the replacement of the PF6-counter-anion with chloride using a novel synthesis method. FY26.PF6 and FY26.Cl displayed similar in vitro cytoxicity in two cancer cell models. We then show the moderate and late anticancer efficacy of FY26.PF6 and FY26.Cl in a subcutaneous murine hepatocarcinoma mouse model. Both efficacy and tolerability varied according to FY26 circadian dosing time in hepatocarcinoma tumour-bearing mice. Tumour and liver uptake of the drug were determined over 48 h following FY26.Cl administration at Zeitgeber 6 (ZT6), when the drug is least toxic (in the middle of the light span when mice are resting). Our studies suggest the need to administer protracted low doses of FY26 at ZT6 in order to optimize its delivery schedule, for example through the use of chrono-releasing nanoparticles

    Draft genome sequence of Sclerospora graminicola, the pearl millet downy mildew pathogen:Genome sequence of pearl millet downy mildew pathogen

    Get PDF
    Sclerospora graminicola pathogen is one of the most important biotic production constraints of pearl millet worldwide. We report a de novo whole genome assembly and analysis of pathotype 1. The draft genome assembly contained 299,901,251 bp with 65,404 genes. Pearl millet [Pennisetum glaucum (L.) R. Br.], is an important crop of the semi-arid and arid regions of the world. It is capable of growing in harsh and marginal environments with highest degree of tolerance to drought and heat among cereals (1). Downy mildew is the most devastating disease of pearl millet caused by Sclerospora graminicola (sacc. Schroet), particularly on genetically uniform hybrids. Estimated annual grain yield loss due to downy mildew is approximately 10?80 % (2-7). Pathotype 1 has been reported to be the highly virulent pathotype of Sclerospora graminicola in India (8). We report a de novo whole genome assembly and analysis of Sclerospora graminicola pathotype 1 from India. A susceptible pearl millet genotype Tift 23D2B1P1-P5 was used for obtaining single-zoospore isolates from the original oosporic sample. The library for whole genome sequencing was prepared according to the instructions by NEB ultra DNA library kit for Illumina (New England Biolabs, USA). The libraries were normalised, pooled and sequenced on Illumina HiSeq 2500 (Illumina Inc., San Diego, CA, USA) platform at 2 x100 bp length. Mate pair (MP) libraries were prepared using the Nextera mate pair library preparation kit (Illumina Inc., USA). 1 ?g of Genomic DNA was subject to tagmentation and was followed by strand displacement. Size selection tagmented/strand displaced DNA was carried out using AmpureXP beads. The libraries were validated using an Agilent Bioanalyser using DNA HS chip. The libraries were normalised, pooled and sequenced on Illumina MiSeq (Illumina Inc., USA) platform at 2 x300 bp length. The whole genome sequencing was performed by sequencing of 7.38 Gb with 73,889,924 paired end reads from paired end library, and 1.15 Gb with 3,851,788 reads from mate pair library generated from Illumina HiSeq2500 and Illumina MiSeq, respectively. The sequences were assembled using various assemblers like ABySS, MaSuRCA, Velvet, SOAPdenovo2, and ALLPATHS-LG. The assembly generated by MaSuRCA (9) algorithm was observed superior over other algorithms and hence used for scaffolding using SSPACE. Assembled draft genome sequence of S. graminicola pathotype 1 was 299,901,251 bp long, with a 47.2 % GC content consisting of 26,786 scaffolds with N50 of 17,909 bp with longest scaffold size of 238,843 bp. The overall coverage was 40X. The draft genome sequence was used for gene prediction using AUGUSTUS. The completeness of the assembly was investigated using CEGMA and revealed 92.74% proteins completely present and 95.56% proteins partially present, while BUSCO fungal dataset indicated 64.9% complete, 12.4% fragmented, 22.7% missing out of 290 BUSCO groups. A total of 52,285 predicted genes were annotated using BLASTX and 38,120 genes were observed with significant BLASTX match. Repetitive element analysis in the assembly revealed 8,196 simple repeats, 1,058 low complexity repeats and 5,562 dinucleotide to hexanucleotide microsatellite repeats.publishersversionPeer reviewe
    corecore