355 research outputs found

    Unsteady MHD Convective Heat and Mass Transfer of a Casson Fluid Past a Semi-infinite Vertical Permeable Moving Plate with Heat Source/Sink

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    In this paper, the effects of heat and mass transfer on an unsteady MHD flow of a Casson fluid past a semi-infinite moving vertical plate with heat source/sink are investigated. The governing equations are transformed into a system of linear partial differential equations using appropriate non-dimensional variables. The resulting equations are solved analytically using perturbation technique. Further the expressions for velocity, temperature and concentration are obtained with the help of boundary conditions. Finally the effects of various parameters on velocity, temperature and concentration are shown in graphs.  It is found that velocity increases as Casson parameter increases and temperature increases as heat absorption coefficient decreases. Keywords: Casson parameter, MHD, Heat source/sink, Heat and mass transfer

    New age data on the geological evolution of Southern India

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    The Peninsular Gneisses of Southern India developed over a period of several hundred Ma in the middle-to-late Archaean. Gneisses in the Gorur-Hassan area of southern Karnataka are the oldest recognized constituents: Beckinsale et al. reported a preliminary Rb-Sr whole-rock isochron age of 33558 + or - 66 Ma, but further Rb-Sr and Pb/Pb whole-rock isochron determinations indicate a slightly younger, though more precise age of ca 3305 Ma (R. D. Beckinsale, Pers. Comm.). It is well established that the Peninsular Gneisses constitute basement on which the Dharwar schist belts were deposited. Well-documented exposures of unconformities, with basal quartz pebble conglomerates of the Dharwar Supergroup overlying Peninsular Gneisses, have been reported from the Chikmagalur and Chitradurga areas, and basement gneisses in these two areas have been dated by Rb-Sr and Pb/Pb whole-rock isochron methods at ca 3150 Ma and ca 3000 Ma respectively. Dharwar supracrustal rocks of the Chitradurga schist belt are intruded by the Chitradurga Granite, dated by a Pb/Pb whole-rock isochron at 2605 + or - 18 Ma. These results indicate that the Dharwar Supergroup in the Chitradurga belt was deposited between 3000 Ma and 2600 Ma

    Transition Metal Doping in CdS Quantum Dots: Diffusion, Magnetism, and Ultrafast Charge Carrier Dynamics

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    Transition metal (TM) doping in pristine II-VI semiconductor quantum dots (QDs) is known to add several otherwise unavailable properties by introducing midgap states in the host material. Albeit being extensively investigated, the periodicity of the observed properties with respect to the electronic structure has not been attempted so far. In this work, we investigate CdS QDs doped with several different TM ions (Mn, Fe, Co, Ni, and Cu) using extended X-ray absorption fine structure spectroscopy to study dopant-induced structural perturbations and femtosecond transient absorption (TA) spectroscopy to study the ultrafast charge carrier dynamics. This provides solid evidence for the origin of magnetization in doped QDs that has been lacking despite extensive studies. Further, we demonstrate that the ionic radius and the dopant oxidation state play crucial roles in determining the dopant-anion bond lengths. Based on the investigation of the relaxation pathways of excited charge carriers using ultrafast TA spectroscopy, we hypothesize that there exists photoinduced switching between multiple oxidation states in some dopants

    Studies on the phytoplankton of the west coast of India Part III. Seasonal Variation of the Phytoplankters and Environmental Factors

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    In this part of the studies, the seasonal distribution of the constituent elements of the phytoplankton as also the meteorological and hydrological conditions during the concerned period are presented based on data gathered over a period of five years by examination by the senior author of over 1,000 samples of plankton collection

    Spontaneous splenic rupture in Waldenstrom's macroglobulinemia: a case report

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    <p>Abstract</p> <p>Introduction</p> <p>We report the case of a patient with Waldenstrom's macroglobulinemia complicated by spontaneous splenic rupture.</p> <p>Case presentation</p> <p>A 49-year-old Caucasian woman was referred to our emergency department by her general practitioner following a three-week history of malaise, night sweats, six kilograms of weight loss, intermittent nausea and vomiting, progressive upper abdominal pain and easy bruising. On the fourth day following her admission, she had a rapid clinical deterioration, with subsequent radiological investigations revealing a splenic rupture. Her morphology, biochemistry, flow cytometry and histology were strongly suggestive of Waldenstrom's macroglobulinemia.</p> <p>Conclusions</p> <p>Spontaneous splenic rupture is not an expected complication of low-grade lymphoplasmacytic lymphomas, such as Waldenstrom's macroglobulinemia. To the best of our knowledge, this is the only reported case of early spontaneous splenic rupture due to Waldenstrom's macroglobulinemia. Our case highlights that despite the typical disease course of low-grade hematological malignancies, signs and symptoms of imminent splenic rupture should be considered when formulating a clinical assessment.</p

    Hesperidin Ameliorates Immobilization-Stress-Induced Behavioral and Biochemical Alterations and Mitochondrial Dysfunction in Mice by Modulating Nitrergic Pathway

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    The present study was aimed to evaluate the protective effect of hesperidin against immobilization-stress-induced alterations in biochemical, behavioral, and mitochondrial functions in mice. In many instances neuroscientists have reported that acute immobilization stress for 6 h resulted in anxiety and impaired locomotor activity due to excess oxidative-nitrergic stress, depletion of antioxidant defense mechanisms, and mitochondrial dysfunction in animals. In the present study, 6 h of acute immobilization stress had significantly altered the behavioral (anxiety and memory) and biochemical parameters coupled with mitochondrial dysfunction in Swiss albino mice. Fourteen days of pretreatment with Hesperidin (50 and 100 mg/kg, p.o.) significantly and dose-dependently inhibited the behavioral and biochemical alterations and mitochondrial dysfunction caused by acute immobilization stress. Furthermore, pre-treatment of l-arginine (50 mg/kg, i.p.), a nitric oxide precursor, reversed the protective effect of Hesperidin (50 and 100 mg/kg) (P < 0.05). In contrast, pretreatment of l-NAME (5 mg/kg, i.p.), a nitric oxide synthase inhibitor, potentiated the protective effect of Hesperidin (P < 0.05). These results suggest the possible involvement of nitrergic pathway in the protective effect Hesperidin against immobilization-stress-induced behavioral, biochemical, and mitochondrial dysfunction in mice

    Method For Increasing The Rate Of Heat Transfer Of Wood Fibres

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    The present invention relates to a method for increasing the rate of heat transfer of wood boards by the use of nano particles of certain metal oxides. The invention relates to increasing the thermal conductivity of wood fibers during manufacturing of wood composites. It reduces the pressing time during production thereby increasing the overall produc tion rate of wood composites and also increasing their strength and Smoothness of Surface
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