488 research outputs found

    Magnetohydrodynamic free convection boundary layer Flow of non-Newtonian tangent hyperbolic fluid from a vertical permeable cone with variable temperature

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    The nonlinear, non-isothermal steady-state boundary layer flow and heat transfer of an incompressible tangent hyperbolic non-Newtonian (viscoelastic) fluid from a vertical permeable cone with magnetic field are studied. The transformed conservation equations are solved numerically subject to physically appropriate boundary conditions using the second-order accurate implicit finite difference Keller-box technique. The numerical code is validated with previous studies. The influence of a number of emerging non-dimensional parameters, namely a Weissenberg number (We), rheological power law index (m), surface temperature exponent (n), Prandtl number (Pr), magnetic parameter (M) suction/injection parameter (fw) and dimensionless tangential coordinate (Îľ) on velocity and temperature evolution in the boundary layer regime, is examined in detail. Furthermore, the effects of these parameters on surface heat transfer rate and local skin friction are also investigated. It is observed that velocity, surface heat transfer rate and local skin friction are reduced with increasing Weissenberg number, but temperature is increased. Increasing m enhances velocity and surface heat transfer rate but reduces temperature and local skin friction. An increase in non-isothermal power law index (n) is observed to decrease the velocity and temperature. Increasing magnetic parameter (M) is found to decrease the velocity and increase the temperature. Overall, the primary influence on free convection is sustained through the magnetic body force parameter, M, and also the surface mass flux (injection/suction) parameter, fw. The rheological effects, while still prominent, are not as dramatic. Boundary layers (both hydrodynamic and thermal) are, therefore, most strongly modified by the applied magnetic field and wall mass flux effect. The study is pertinent to smart coatings, e.g., durable paints, aerosol deposition processing and water-based solvent thermal treatment in chemical engineering

    Melting heat transfer analysis on magnetohydrodynamics buoyancy convection in an enclosure : a numerical study

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    Therollof melting heat transfer on magnetohydrodynamic natural convection in a square enclosurewithheatingof the bottom wall is examinednumericallyin this article.The dimensionlessgoverning partial differential equations are transformed into vorticity and stream functionformulationand then solved using the finite difference method(FDM). The effects of thermal Rayleigh number(Ra), melting parameter(M) and Hartmann number(Ha) are illustrated graphically.With an increasing melting parameter and Rayleigh number, the rate of fluid flow and temperature gradients are seen to increase. And in the presence of magnetic field, the temperature gradient reduces and hence the conductionmechanism dominated for larger Ha. Greater heat transfer rate is observed in the case of uniform heating compared with non-uniform case. The average Nusselt number reduces with increasing magnetic parameterin the both cases of heating of bottom wall

    Novel microfilaricidal activity of nanosilver

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    Sunil K Singh1, Kalyan Goswami2, Richa D Sharma2, Maryada VR Reddy2, Debabrata Dash11Department of Biochemistry, Institute of Medical Sciences, Banaras Hindu University, Varanasi, 2Department of Biochemistry, Mahatma Gandhi Institute of Medical Sciences, Sevagram, IndiaPurpose: The currently available drug repertoire against lymphatic filariasis, a major health hazard in the developing world, is inadequate and is fraught with serious limitations. Thus, the development of an effective antifilarial strategy has become a global research thrust mandated by the World Health Organization. Nanoparticles of silver endowed with antibacterial potency are known to induce apoptosis in eukaryotic cells. The present study was designed to investigate the possible microfilaricidal efficacy of silver nanoparticles and to establish the validity of apoptotic rationale in antifilarial drug designing.Methods: This report analyzed the effect of nanoparticles of silver as well as gold (size range: 10–15 nm) on the microfilariae of Brugia malayi obtained from the lavage of peritoneal cavities of infected jirds (Meriones unguiculatus). The study included a microfilarial motility assay, a trypan blue exclusion test, a poly(adenosine diphosphate-ribose) polymerase activity study, ethidium bromide/acridine orange differential staining, and transmission, as well as scanning electron microscopic evaluation of ultrastructural changes in microfilariae.Results: The study demonstrates that nanoparticles of silver, but not of gold, elicited significant loss in microfilarial motility. Differential staining of parasites with ethidium bromide and acridine orange, poly(adenosine diphosphate-ribose) polymerase activity in microfilarial lysate, and electron microscopic findings underscored apoptotic death of parasites attributable to nanosilver. In a trypan blue exclusion test, the 50% lethal dose of nanosilver was measured to be 101.2 µM, which was higher than the recorded complete inhibitory concentration value (50.6 µM), thus supporting nanosilver as a potential drug candidate against lymphatic filariasis.Conclusion: The present report provides the first ever conclusive proof in support of apoptosis as a novel stratagem in antifilarial drug designing and nanoscale silver as a valid lead in research on antifilarial therapeutics. The main embargo about the current drug diethylcarbamazine citrate is its empirical use without rationale. Effective microfilaricidal activity of nanosilver at relatively low concentrations as reported in this study, with evidence of the induction of apoptosis in microfilariae, projects nanosilver as a potential drug adjuvant against lymphatic filariasis. The much higher 50% lethal dose value of nanosilver compared to the complete inhibitory concentration value reported in this study argues in favor of a safe therapeutic window of this agent in its antifilarial efficacy.Keywords: silver nanoparticles, apoptosis, lymphatic filariasis, microfilaricidal agent, parasitic disease

    In vitro shoot multiplication and conservation of Caralluma bhupenderiana Sarkaria - an endangered medicinal plant from South India

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    An efficient protocol was described for the rapid in vitro multiplication of an endangered medicinal plant, Caralluma bhupenderiana Sarkaria, via enhanced axillary bud proliferation from nodal explants collected from young shoots of six-months-old plant. The physiological effects of growth regulators [6- Benzyladenine (BA), kinetin (Kn), 2-Isopentyl adenine (2iP), zeatin (Zn), indole-3-acetic acid (IAA), indole-3-butyric acid (IBA)], different strengths of Murashige and Skoog (MS) medium and various pH levels on in vitro morphogenesis were investigated. The highest number (8.40 + 0.50) of shoots and the maximum average shoot length (3.2 ± 0.31 cm) were recorded on MS medium supplemented with BA (8.87 μM) at pH 5.8. Rooting was best achieved on half-strength MS medium augmented with NAA (2.69 μM). The plantlets regenerated in vitro with well-developed shoot and roots were successfully established in pots containing peat mass and garden manure in 1:1 ratio and grown in a greenhouse with 80% survival rate. The regenerated plants did not show any immediate detectable phenotypic variation.Key words: Apocynaceae, asclepiadoideae, conservation, micro-propagation, endangered, Caralluma bhupenderiana

    Reconstructing Indian-Australian phylogenetic link

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    <p>Abstract</p> <p>Background</p> <p>An early dispersal of biologically and behaviorally modern humans from their African origins to Australia, by at least 45 thousand years via southern Asia has been suggested by studies based on morphology, archaeology and genetics. However, mtDNA lineages sampled so far from south Asia, eastern Asia and Australasia show non-overlapping distributions of haplogroups within pan Eurasian M and N macrohaplogroups. Likewise, support from the archaeology is still ambiguous.</p> <p>Results</p> <p>In our completely sequenced 966-mitochondrial genomes from 26 relic tribes of India, we have identified seven genomes, which share two synonymous polymorphisms with the M42 haplogroup, which is specific to Australian Aborigines.</p> <p>Conclusion</p> <p>Our results showing a shared mtDNA lineage between Indians and Australian Aborigines provides direct genetic evidence of an early colonization of Australia through south Asia, following the "southern route".</p

    Walker-Independent Features for Gait Recognition from Motion Capture Data

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    MoCap-based human identification, as a pattern recognition discipline, can be optimized using a machine learning approach. Yet in some applications such as video surveillance new identities can appear on the fly and labeled data for all encountered people may not always be available. This work introduces the concept of learning walker-independent gait features directly from raw joint coordinates by a modification of the Fisher’s Linear Discriminant Analysis with Maximum Margin Criterion. Our new approach shows not only that these features can discriminate different people than who they are learned on, but also that the number of learning identities can be much smaller than the number of walkers encountered in the real operation

    Endoscopic ultrasound guided radiofrequency ablation, for pancreatic cystic neoplasms and neuroendocrine tumors

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    AIM: To outline the feasibility, safety, adverse events and early results of endoscopic ultrasound (EUS)-radiofrequency ablation (RFA) in pancreatic neoplasms using a novel probe. METHODS: This is a multi-center, pilot safety feasibility study. The intervention described was radiofrequency ablation (RF) which was applied with an innovative monopolar RF probe (1.2 mm Habib EUS-RFA catheter) placed through a 19 or 22 gauge fine needle aspiration (FNA) needle once FNA was performed in patients with a tumor in the head of the pancreas. The Habib™ EUS-RFA is a 1 Fr wire (0.33 mm, 0.013") with a working length of 190 cm, which can be inserted through the biopsy channel of an echoendoscope. RF power is applied to the electrode at the end of the wire to coagulate tissue in the liver and pancreas. RESULTS: Eight patients [median age of 65 (range 27-82) years; 7 female and 1 male] were recruited in a prospective multicenter trial. Six had a pancreatic cystic neoplasm (four a mucinous cyst, one had intraductal papillary mucinous neoplasm and one a microcystic adenoma) and two had a neuroendocrine tumors (NET) in the head of pancreas. The mean size of the cystic neoplasm and NET were 36.5 mm (SD ± 17.9 mm) and 27.5 mm (SD ± 17.7 mm) respectively. The EUS-RFA was successfully completed in all cases. Among the 6 patients with a cystic neoplasm, post procedure imaging in 3-6 mo showed complete resolution of the cysts in 2 cases, whilst in three more there was a 48.4% reduction [mean pre RF 38.8 mm (SD ± 21.7 mm) vs mean post RF 20 mm (SD ± 17.1 mm)] in size. In regards to the NET patients, there was a change in vascularity and central necrosis after EUS-RFA. No major complications were observed within 48 h of the procedure. Two patients had mild abdominal pain that resolved within 3 d. CONCLUSION: EUS-RFA of pancreatic neoplasms with a novel monopolar RF probe was well tolerated in all cases. Our preliminary data suggest that the procedure is straightforward and safe. The response ranged from complete resolution to a 50% reduction in size

    Allelic variants of DYX1C1 are not associated with dyslexia in India

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    Dyslexia is a hereditary neurological disorder that manifests as an unexpected difficulty in learning to read despite adequate intelligence, education, and normal senses. The prevalence of dyslexia ranges from 3 to 15% of the school aged children. Many genetic studies indicated that loci on 6p21.3, 15q15-21, and 18p11.2 have been identified as promising candidate gene regions for dyslexia. Recently, it has been suggested that allelic variants of gene, DYX1C1 influence dyslexia. In the present study, exon 2 and 10 of DYX1C1 has been analyzed to verify whether these single nucleotide polymorphisms (SNPs) influence dyslexia, in our population. Our study identified 4 SNPs however, none of these SNPS were found to be significantly associated with dyslexia suggesting DYX1C1 allelic variants are not associated with dyslexia

    The STRIPES Trial - Support to Rural India's Public Education System

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    Background Performance of primary school students in India lags far below government expectations, and major disparity exists between rural and urban areas. The Naandi Foundation has designed and implemented a programme using community members to deliver after-school academic support for children in over 1,100 schools in five Indian states. Assessments to date suggest that it might have a substantial effect. This trial aims to evaluate the impact of this programme in villages of rural Andhra Pradesh and will compare test scores for children in three arms: a control and two intervention arms. In both intervention arms additional after-school instruction and learning materials will be offered to all eligible children and in one arm girls will also receive an additional 'kit' with a uniform and clothes. Methods/Design The trial is a cluster-randomised controlled trial conducted in conjunction with the CHAMPION trial. In the CHAMPION trial 464 villages were randomised so that half receive health interventions aiming to reduce neonatal mortality. STRIPES will be introduced in those CHAMPION villages which have a public primary school attended by at least 15 students at the time of a baseline test in 2008. 214 villages of the 464 were found to fulfil above criteria, 107 belonging to the control and 107 to the intervention arm of the CHAMPION trial. These latter 107 villages will serve as control villages in the STRIPES trial. A further randomisation will be carried out within the 107 STRIPES intervention villages allocating half to receive an additional kit for girls on the top of the instruction and learning materials. The primary outcome of the trial is a composite maths and language test score. Discussion The study is designed to measure (i) whether the educational intervention affects the exam score of children compared to the control arm, (ii) if the exam scores of girls who receive the additional kit are different from those of girls living in the other STRIPES intervention arm. One of the goals of the STRIPES trial is to provide benefit to the controls of the CHAMPION trial. We will also conduct a cost-benefit analysis in which we calculate the programme cost for 0.1 standard deviation improvement for both intervention arms

    Global prospective case series of ERCPs using a single-use duodenoscope

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    Background The first commercialized single-use duodenoscope was cleared by the US Food and Drug Administration in December 2019. Data regarding endoscopic retrograde cholangiopancreatography (ERCP) using a single-use duodenoscope are needed on a broader range of cases conducted by endoscopists with varying levels of experience in a wide range of geographic areas. Methods 61 endoscopists at 22 academic centers in 11 countries performed ERCP procedures in adult patients aged ? 18. Outcomes included ERCP completion for the intended indication, rate of crossover to a reusable endoscope, device performance ratings, and serious adverse events (SAEs). Results Among 551 patients, 236 (42.8 %) were aged &gt;65, 281 (51.0 %) were men, and 256 (46.5 %) had their procedure as an inpatient. ERCPs included 196 (35.6 %) with American Society for Gastrointestinal Endoscopy complexity of grades 3 4. A total of 529 ERCPs (96.0 %) were completed: 503 (91.3 %) using only the single-use duodenoscope, and 26 (4.7 %) with crossover to a reusable endoscope. There were 22 ERCPs (4.0 %) that were not completed, of which 11 (2.0 %) included a crossover and 11 (2.0 %) were aborted cases (no crossover). Median ERCP completion time was 24.0 minutes. Median overall satisfaction with the single-use duodenoscope was 8.0 (scale of 1 to 10 [best]). SAEs were reported in 43 patients (7.8 %), including 17 (3.1 %) who developed post-ERCP pancreatitis. Conclusions In academic medical centers over a wide geographic distribution, endoscopists with varying levels of experience using the first marketed single-use duodenoscope had good ERCP procedural success and reported high performance ratings for this device.</p
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