13,356 research outputs found

    Flow of a Dusty Viscous Liquid Through Rectangular Channel

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    The Laminar flow of an unsteady liquid with uniform distribution of dust particles through a rectangular channel under the influence of exponential pressure gradient with respect to time has been investigated. The influence of the presence of the dust particles on fluid particles is discussed and graphs of velocity profile are drawn

    Stability of a Non Newtonian Fluid Between Two Concentric Rotating Porous Cylinders

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    The stability of non-Newtonian fluid confined between two concentric rotating porous cylinders has been examined. The critical determines the on set of instability has been determined as a function of 'a' (wave length) and S (cross viscous parameter). The variation of the critical Taylor number with S, suction parameter lambda and radial velocity distribution have been shown. It has been found that the effect of suction at the outer cylinder is to stabilize the flow whereas the injection destabilizes the flow. The presence of suction or injection does not affect radial velocity curves or vortex cells

    The Stability of Non Newtonian Fluid Between the Two Rotating Porous Cylinders (Wide Gap Case)

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    This paper is primarily concerned with the stability of the non Newtonian fluid between two porous cylinders in the case of wide gap. The problem is discussed for Mhu>0,Mhu=0 and Mhu,0. The results show that the Taylor number depends on the gap size in the case of non Newtonian fluids and the presence of suction stabilizes the flow whereas the injection destabilizes the flow. Its is found the stability of the fluid decreases when the gap increases. The non Newtonian fluid is less stable when compared to the Newtonian fluid in the case of wide gap. It is also found in the case of wide gap(for non Newtonian fluid and the cylinders are counter rotating equally) the application of injection at the outer cylinder disturbs the radial velocity will not effect any appreciable change or disturbance in the vortex cell pattern at the onset of instability

    Far-infrared study of K giants in the solar neighborhood: Connection between Li enrichment and mass-loss

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    We searched for a correlation between the two anomalous properties of K giants: Li enhancement and IR excess from an unbiased survey of a large sample of RGB stars. A sample of 2000 low-mass K giants with accurate astrometry from the Hipparcos catalog was chosen for which Li abundances have been determined from low-resolution spectra. Far-infrared data were collected from the WISEWISE and IRASIRAS catalogs. To probe the correlation between the two anomalies, we supplemented 15 Li-rich K giants discovered from this sample with 25 known Li-rich K giants from other studies. Dust shell evolutionary models and spectral energy distributions were constructed using the code DUSTY to estimate different dust shell properties, such as dust evolutionary time scales, dust temperatures, and mass-loss rates. Among 2000 K giants, we found about two dozen K giants with detectable far-IR excess, and surprisingly, none of them are Li-rich. Similarly, the 15 new Li-rich K giants that were identified from the same sample show no evidence of IR excess. Of the total 40 Li-rich K giants, only 7 show IR excess. Important is that K giants with Li enhancement and/or IR excess begin to appear only at the bump on the RGB. Results show that K giants with IR excess are very rare, similar to K giants with Li enhancement. This may be due to the rapid differential evolution of dust shell and Li depletion compared to RGB evolutionary time scales. We also infer from the results that during the bump evolution, giants probably undergo some internal changes, which are perhaps the cause of mass-loss and Li-enhancement events. However, the available observational results do not ascertain that these properties are correlated. That a few Li-rich giants have IR excess seems to be pure coincidence.Comment: Accepted for Publication in Astronomy & Astrophysics, 6 figures, 5 tables, 19 page

    Anthelmintic Activity of Trikatu Churna and its Ingredients

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    The alcoholic extract of Trikatu churna and its ingredients were evaluated for anthelmintic activity. The dried fruits of Piper nigrum L. (Piperaceae), Piper longum L. (Piperaceae) and rhizome of Zingiber officinale Roscoe. (Zingiberaceae) were powdered and mixed together in equiproportions to get a polyherbal formulation, Trikatu churna. All these three ingredients are spicy, commonly used in our daily diet, also well known for their tremendous therapeutic potential, since from the Vedic period. The alcoholic extract of Trikatu churna and its ingredients were screened for preliminary phytochemical studies and also tested for anthelmintic activity against Pheritima posthuma and recorded the time taken for induction of paralysis and death. Piperazine citrate (10 mg/ml) was included as standard reference and distilled water as control. The results demonstrated that, the extracts of Trikatu churna and its plant ingredients showed the presence of alkaloids, flavonoids, tannins, lignins and steroids, these test samples were also exhibited potent anthelmintic activity, but the highest activity was noticed in Trikatu churna, this might be due to the multifunctional effect of all the three plant ingredients of Trikatu churna. Based on the above results, it is confirmed that, combination of Piper nigrum, Piper longum and Zingiber officinale in Trikatu churna offered promising anthelmintic effect than using the ingredients alone

    Optical Absorption Studies on Ferrous Ion Doped CMDH Crystals

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    New Experimental Limit on the Electric Dipole Moment of the Electron in a Paramagnetic Insulator

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    We report results of an experimental search for the intrinsic Electric Dipole Moment (EDM) of the electron using a solid-state technique. The experiment employs a paramagnetic, insulating gadolinium gallium garnet (GGG) that has a large magnetic response at low temperatures. The presence of the eEDM would lead to a small but non-zero magnetization as the GGG sample is subject to a strong electric field. We search for the resulting Stark-induced magnetization with a sensitive magnetometer. Recent progress on the suppression of several sources of background allows the experiment to run free of spurious signals at the level of the statistical uncertainties. We report our first limit on the eEDM of (5.57±7.98±0.12)×(-5.57 \pm 7.98 \pm 0.12)\times1025^{-25}e\cdotcm with 5 days of data averaging.Comment: 9 pages, 9 figures, Revtex 4.

    Validation of Molecular Markers Genetically Linked to S-Cytoplasm and Restoration-of-fertility (Rf) Loci in Hot Pepper (Capsicum annuum L.)

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    Existence of CGMS system in hot pepper is due to the rearrangements in the mitochondrial genome and is largely used in economized and pure F 1 hybrid seed production around the world. The orf456, a new ORF present at flanking region of the coxII gene at the 3’ end, was distinguished male sterile cytoplasm in hot peppers along with atp6-2gene. In the current study, eighteen pepper genotypes (nine each of A and corresponding B lines) of varied origin were used to validate with two male sterile cytoplasm (S-cytoplasm) specific sequence characterised amplified region (SCAR) markers viz., atp6-2 (875 bp) and orf456 (456 bp) and one restoration-of-fertility (Rf) locus specific marker, CRF (550 bp). The results clearly showed that the presence of CMS-S-cytoplasm and absence of restoration-of-fertility (Rf) gene in the pepper genotypes studied and is comparable with the phenotypic data. In view of the outcomes it has been reasoned that the accessible S and Rf markers available in the public domain are reproducible and can be promptly utilized for marker assisted selection (MAS) in hot pepper crop improvement program

    Integrated Multiple Features for Tumor Image Retrieval Using Classifier and Feedback Methods

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    AbstractThe content based image retrieval method greatly assists in retrieving medical images close to the query image from a large database basing on their visual features. This paper presents an effective approach in which the region of the object is extracted with the help of multiple features ignoring the background of the object by employing edge following segmentation method followed by extracting texture and shape characteristics of the images. The former is extracted with the help of Steerable filter at different orientations and radial Chebyshev moments are used for extracting the later. Initially the images similar to the query image are extracted from a large group of medical images. Then the search is by accelerating the retrieval process with the help of Support Vector Machine (SVM) classifier. The performance of the retrieval system is enhanced by adapting the subjective feedback method. The experimental results show that the proposed region based multiple features and integrated with classifier and subjective feedback method yields better results than classical retrieval systems

    IN VITRO HEPATOPROTECTIVE EFFECT OF ECHINOCHLOA COLONA ON ETHANOL-INDUCED OXIDATIVE DAMAGE IN HEPG2 CELLS

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      Objective: The current study was aimed to evaluate the methanolic extract of caryopses of Echinochloa colona (ECME) for its in vitro hepatoprotective activity against ethanol in HepG2 cell lines.Methods: In this regard, the cytotoxicity studies were conducted for the extract, ECME using 3-(4,5-dimethythiazol- 2-yl)-2,5-diphenyl tetrazolium bromide assay to determine the inhibitory concentration 50% value based on which, the doses 50, 100, and 200 μg/ml were selected for the hepatoprotective studies in HepG2 cell lines. The toxicity was induced using ethanol (100 mM). The in vitro hepatoprotective activity of the extract was assessed based on the changes in the level of biochemical parameters such as aspartate aminotransferase, alanine aminotransferase, and lactate dehydrogenase.Results: The extract, ECME has shown a dose-dependent cytoprotective activity with maximum protection at 200 μg/ml. The percentage cell viability of the extract, ECME at 200 μg/ml was more, i.e., 69.33% which was well comparable to that of standard drug, silymarin (100 μg/ml).Conclusion: The study revealed that the extract had shown significant hepatoprotective activity at all the test doses against ethanol-induced cytotoxity assay
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