42 research outputs found

    Interaction of Glucose with ZnO Nanoparticles

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    We report the results of the extent of interaction as well as the formation of a bioconjugate of glucose with Zinc Oxide nano particles (ZnO NPs) to understand the non-invasive monitoring of glucose by semiconductor NPs. We performed an array of photophysical as well as microscopic measurements to quantify the interaction between ZnO NPs and glucose. We have found that time constant of interaction (t1) 18.47 min for the binding glucose with surface of ZnO NPs and follows a single exponential association process. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3596

    Environment-Friendly Synthesis of Undoped and Cu doped ZnO Nanoparticles and Study of their Optical Absorption Properties towards Biological Applications

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    Wet chemical method is a simple and cost-effective way to synthesize nanoparticles of high yield and mass production compared to other conventional methods. Besides, it does not require the maintenance of rigorous experimental conditions like high temperature, low pressure or flow of carrier gases. We have followed a simple wet chemical method to synthesize pure and Cu doped ZnO nanoparticles. Absorption spectroscopic study yields the absorption behavior of a material over a wide range of the electromagnetic spectrum. Absorption study of the synthesized undoped ZnO and Cu/ZnO reveals that doping with Cu decreases the absorption coefficient. It clearly indicates that the scattering of photons by phonons reduces due to Cu doping. The Urbach energy is an important parameter to understand the degree of disorder of phonon states in a material. It also enables us to study the dependence of the absorption coefficient on the wavelength of incident photons of energies lower than the band gap energy. For pure ZnO, the Urbach energy was calculated to be 0.511 eV and decreased to 0.483 eV upon doping with Cu in ZnO. The extinction coefficient was also calculated to understand the optical absorption process in the material

    Chemical synthesis and optical properties of ZnO nanoparticles

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    We report here a simple wet chemical process to synthesize ZnO nanoparticles. The morphology of the nanoparticles was observed in field emission scanning electron microscope. The nanoparticles have average diameter ~ 100 nm. The optical property of the synthesized ZnO nanoparticles was investigated using UVvisible absorption spectra. The synthesized nanoparticles exhibit strong absorption at ~ 279 nm. The band gap of the nanoparticles was calculated from the absorption spectrum and found to be 3.76 eV. Thus the synthesized ZnO nanoparticles will be useful in various optoelectronic applications

    Interaction of Glucose with ZnO Nanoparticles

    Get PDF
    We report the results of the extent of interaction as well as the formation of a bioconjugate of glucose with Zinc Oxide nano particles (ZnO NPs) to understand the non-invasive monitoring of glucose by semiconductor NPs. We performed an array of photophysical as well as microscopic measurements to quantify the interaction between ZnO NPs and glucose. We have found that time constant of interaction (t1) 18.47 min for the binding glucose with surface of ZnO NPs and follows a single exponential association process. When you are citing the document, use the following link http://essuir.sumdu.edu.ua/handle/123456789/3596

    Viability of Noether symmetry of F(R) theory of gravity

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    Canonization of F(R) theory of gravity to explore Noether symmetry is performed treating R - 6(\frac{\ddot a}{a} + \frac{\dot a^2}{a^2} + \frac{k}{a^2}) = 0 as a constraint of the theory in Robertson-Walker space-time, which implies that R is taken as an auxiliary variable. Although it yields correct field equations, Noether symmetry does not allow linear term in the action, and as such does not produce a viable cosmological model. Here, we show that this technique of exploring Noether symmetry does not allow even a non-linear form of F(R), if the configuration space is enlarged by including a scalar field in addition, or taking anisotropic models into account. Surprisingly enough, it does not reproduce the symmetry that already exists in the literature (A. K. Sanyal, B. Modak, C. Rubano and E. Piedipalumbo, Gen.Relativ.Grav.37, 407 (2005), arXiv:astro-ph/0310610) for scalar tensor theory of gravity in the presence of R^2 term. Thus, R can not be treated as an auxiliary variable and hence Noether symmetry of arbitrary form of F(R) theory of gravity remains obscure. However, there exists in general, a conserved current for F(R) theory of gravity in the presence of a non-minimally coupled scalar-tensor theory (A. K. Sanyal, Phys.Lett.B624, 81 (2005), arXiv:hep-th/0504021 and Mod.Phys.Lett.A25, 2667 (2010), arXiv:0910.2385 [astro-ph.CO]). Here, we briefly expatiate the non-Noether conserved current and cite an example to reveal its importance in finding cosmological solution for such an action, taking F(R) \propto R^{3/2}.Comment: 16 pages, 1 figure. appears in Int J Theoretical Phys (2012

    Synthesis and Optical Absorption Properties of Copper Oxide Nanoparticles for Applications in Transparent Surface Coatings and Solar Cells

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    A simple wet chemical method has been successfully deployed to synthesize CuO nanoparticles (NPs) by using copper chloride and lithium hydroxide as the precursors. X-ray diffraction study revealed that the synthesized CuO is highly crystalline and pure. The synthesized CuO NPs has very high transparency in the visible region of wavelength. The band gap of the CuO NPs was found to be 1.54 eV

    Noether gauge symmetry for f(R)f(R) gravity in Palatini formalism

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    In this study, we consider a flat Friedmann-Robertson-Walker (FRW) universe in the context of Palatini f(R)f(R) theory of gravity. Using the dynamical equivalence between f(R)f(R) gravity and scalar-tensor theories, we construct a point Lagrangian in the flat FRW spacetime. Applying {\em Noether gauge symmetry approach} for this f(R)f(R) Lagrangian we find out the form of f(R)f(R) and the exact solution for cosmic scale factor. It is shown that the resulting form of f(R)f(R) yield a power-law expansion for the scale factor of the universe.Comment: 7 pagese, no figures; Published in Astrophysics & Space Science. Some minor corrections have been mad

    LRS Bianchi type I universes exhibiting Noether symmetry in the scalar-tensor Brans-Dicke theory

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    Following up on hints of anisotropy in the cosmic microwave background radiation (CMB) data, we investigate locally rotational symmetric (LRS) Bianchi type I spacetimes with non-minimally coupled scalar fields. To single out potentially more interesting solutions, we search for Noether symmetry in this system. We then specialize to the Brans-Dicke (BD) field in such a way that the Lagrangian becomes degenerate (nontrivial) and solve the equations for Noether symmetry and the potential that allows it. Then we find the exact solutions of the equations of motion in terms of three parameters and an arbitrary function. We illustrate with families of examples designed to be generalizations of the well-known power-expansion, exponential expansion and Big Rip models in the Friedmann-Robertson-Walker (FRW) framework. The solutions display surprising variation, a large subset of which features late-time acceleration as is usually ascribed to dark energy (phantom or quintensence), and is consistent with observational data.Comment: 25 pages, no figure, to appear in General Relativity and Gravitatio

    Zebrafish Kidney Phagocytes Utilize Macropinocytosis and Ca2+-Dependent Endocytic Mechanisms

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    Background: The innate immune response constitutes the first line of defense against invading pathogens and consists of a variety of immune defense mechanisms including active endocytosis by macrophages and granulocytes. Endocytosis can be used as a reliable measure of selective and non-selective mechanisms of antigen uptake in the early phase of an immune response. Numerous assays have been developed to measure this response in a variety of mammalian and fish species. The small size of the zebrafish has prevented the large-scale collection of monocytes/macrophages and granulocytes for these endocytic assays. Methodology/Principal Findings: Pooled zebrafish kidney hematopoietic tissues were used as a source of phagocytic cells for flow-cytometry based endocytic assays. FITC-Dextran, Lucifer Yellow and FITC-Edwardsiella ictaluri were used to evaluate selective and non-selective mechanisms of uptake in zebrafish phagocytes. Conclusions/Significance: Zebrafish kidney phagocytes characterized as monocytes/macrophages, neutrophils and lymphocytes utilize macropinocytosis and Ca 2+-dependant endocytosis mechanisms of antigen uptake. These cells do not appear to utilize a mannose receptor. Heat-killed Edwardsiella ictaluri induces cytoskeletal interactions for internalization in zebrafish kidney monocytes/macrophages and granulocytes. The proposed method is easy to implement and should prove especially useful in immunological, toxicological and epidemiological research

    A systematic review of outcome and outcome-measure reporting in randomised trials evaluating surgical interventions for anterior-compartment vaginal prolapse: a call to action to develop a core outcome set

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    INTRODUCTION: We assessed outcome and outcome-measure reporting in randomised controlled trials evaluating surgical interventions for anterior-compartment vaginal prolapse and explored the relationships between outcome reporting quality with journal impact factor, year of publication, and methodological quality. METHODS: We searched the bibliographical databases from inception to October 2017. Two researchers independently selected studies and assessed study characteristics, methodological quality (Jadad criteria; range 1-5), and outcome reporting quality Management of Otitis Media with Effusion in Cleft Palate (MOMENT) criteria; range 1-6], and extracted relevant data. We used a multivariate linear regression to assess associations between outcome reporting quality and other variables. RESULTS: Eighty publications reporting data from 10,924 participants were included. Seventeen different surgical interventions were evaluated. One hundred different outcomes and 112 outcome measures were reported. Outcomes were inconsistently reported across trials; for example, 43 trials reported anatomical treatment success rates (12 outcome measures), 25 trials reported quality of life (15 outcome measures) and eight trials reported postoperative pain (seven outcome measures). Multivariate linear regression demonstrated a relationship between outcome reporting quality with methodological quality (β = 0.412; P = 0.018). No relationship was demonstrated between outcome reporting quality with impact factor (β = 0.078; P = 0.306), year of publication (β = 0.149; P = 0.295), study size (β = 0.008; P = 0.961) and commercial funding (β = -0.013; P = 0.918). CONCLUSIONS: Anterior-compartment vaginal prolapse trials report many different outcomes and outcome measures and often neglect to report important safety outcomes. Developing, disseminating and implementing a core outcome set will help address these issues
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