4,981 research outputs found

    Effect of Al doping on the optical phonon spectrum in Mg(1-x)Al(x)B(2)

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    Raman and infrared absorption spectra of Mg(1-x)Al(x)B(2) have been collected for 0<x<0.5 in the spectral range of optical phonons. The x-dependence of the peak frequency, the width and the intensity of the observed Raman lines has been carefully analized. A peculiar x-dependence of the optical modes is pointed out for two different Al doping ranges. In particular the onset of the high-doping structural phase previously observed in diffraction measurements is marked by the appearence of new spectral components at high frequencies. A connection between the whole of our results and the observed suppression of superconductivity in the high doping region is established

    Phase equilibria in the La-Mg-Ge system at 500 &#176;c and crystal structure of the new ternary compounds La11Mg2Ge7 and LaMg3-xGe2

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    The whole 500 \ub0C isothermal section of the La-Mg-Ge ternary system was constructed. The existence and crystal structure of three ternary compounds were confirmed: La2+xMg1-xGe2 (\u3c42, P4/mbm, tP10-Mo2FeB2, 0 64x 640.25), La 4Mg5Ge6 (\u3c43, Cmc21, oS60-Gd4Zn5Ge6) and La4Mg 7Ge6 (\u3c44, C2/m, mS34, own structure type). Five novel compounds were identified and structurally characterized: La 11Mg2Ge7 (\u3c41, P4 2/ncm, tP88-8, own structure type, a=1.21338(5), c=1.57802(6) nm), LaMg3-xGe2 (\u3c45, P 3\u3041c, hP34-0.44, own structure type, x=0.407(5), a=0.78408(4), c=1.45257(7) nm), La 6Mg23Ge (\u3c46, Fm3\u304m, cF120-Zr 6Zn23Si, a=1.46694(6) nm), La4MgGe 10-x (\u3c47, x=0.37(1), C2/m, mS60-1.46, own structure type, a=0.88403(8), b=0.86756(8), c=1.7709(2) nm, \u3b2=97.16\ub0(1) and La2MgGe6 (\u3c48, Cmce, oS72-Ce 2(Ga0.1Ge0.9)7, a=0.8989(2), b=0.8517(2), c=2.1064(3) nm). Disordering phenomena were revealed in several La-Mg-Ge phases in terms of partially occupied sites. The crystal structures of La11Mg2Ge7 and LaMg3-xGe2 are discussed in details. The latter is a 1a3a 7 1a3a 72c superstructure of the LaLi3Sb2 structure type; the symmetry reduction scheme is shown in the B\ue4rnighausen formalism terms. \ua9 2014 Elsevier Inc

    Operating Parameters Optimization for the Production of Liposomes Loaded with Antibodies Using a Supercritical Fluid-Assisted Process

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    Encapsulation of antibodies represents a significant advance to protect and deliver these therapeutics in a controlled manner, increasing the stability requested to cover the temporal gap between particle production and their administration. Furthermore, using encapsulation, extracellular, cell surface, and intracellular targets can be reached. This work examines the feasibility of encapsulating mouse IgG isotype control antibodies within phosphatidylcholine-based liposomes using a supercritical fluid-based process called SuperLip (Supercritical-assisted Liposome formation). This process allows a continuous production of both nano- and micrometric liposomes with high encapsulation efficiency working under mild operative conditions. The effect of some operative parameters has been studied on liposome mean diameter, particle size distribution, and antibody entrapment efficiency, comparing these data with those collected working with liposomes obtained by the thin-layer hydration technique. In particular, the effect of water flow rate and of the antibody loading were studied. Antibody-loaded liposomes with mean diameters in the range between 205 and 501 nm have been obtained by using a supercritical fluid-assisted process. High entrapment efficiencies up to 94% have been calculated

    No measure for culture? Value in the new economy

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    This paper explores articulations of the value of investment in culture and the arts through a critical discourse analysis of policy documents, reports and academic commentary since 1997. It argues that in this period, discourses around the value of culture have moved from a focus on the direct economic contributions of the culture industries to their indirect economic benefits. These indirect benefits are discussed here under three main headings: creativity and innovation, employability, and social inclusion. These are in turn analysed in terms of three forms of capital: human, social and cultural. The paper concludes with an analysis of this discursive shift through the lens of autonomist Marxist concerns with the labour of social reproduction. It is our argument that, in contemporary policy discourses on culture and the arts, the government in the UK is increasingly concerned with the use of culture to form the social in the image of capital. As such, we must turn our attention beyond the walls of the factory in order to understand the contemporary capitalist production of value and resistance to it. </jats:p

    Comparative pharmacokinetic and pharmacodynamic evaluation of branded and generic formulations of meloxicam in healthy male volunteers

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    PURPOSE: The primary aim of the present study was to assess the pharmacokinetic bioequivalence between a generic formulation of meloxicam 15 mg tablets (Meloxicam Hexal) and its respective brand product (Mobic), in order to verify whether the generic product conforms to the regulatory standards of bioequivalence in the postmarketing setting. As a secondary exploratory aim, the pharmacodynamic effects of the two formulations were also evaluated by means of rating scales following hyperalgesia induced by cutaneous freeze injury. SUBJECTS AND METHODS: A single 15 mg dose of generic or branded meloxicam tablets was administered to 24 healthy male volunteers in a crossover fashion. Plasma samples, collected for 24 hours after dosing, were assayed for meloxicam concentration by a validated highperformance liquid chromatography method. RESULTS: THE ANALYSIS OF PHARMACOKINETIC PARAMETERS DID NOT SHOW ANY SIGNIFICANT DIFFERENCE BETWEEN THE TWO MELOXICAM FORMULATIONS: the 90% confidence intervals fell within the acceptance range of 80%-125% (0.84-1.16 for area under the curve [0-24], and 0.89-1.23 for peak concentration). No difference in the pharmacodynamic end point was observed between the two groups. CONCLUSION: The pharmacokinetic profiles of the two meloxicam formulations confirm the regulatory criteria for bioequivalence; pharmacodynamic data indicate a similar antihyperalgesic effect. The two formulations can be used interchangeably in the clinical setting
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