5,565 research outputs found

    Retrieval of cloud spherical albedo from top-of-atmosphere reflectance measurements performed at a single observation angle

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    International audienceThe paper is devoted to the derivation of the simple analytical relationship between the cloud spherical albedo and the cloud reflection function. The relationship obtained can be used for the derivation of the spherical albedo from backscattered solar light measurements performed by radiometers on geostationary and polar orbiting satellites. The example of the application of the technique to MODIS data is shown

    Generation of chirp-free picosecond pulses

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    The frequency spectrum of moderately chirped laser pulses depends upon the portion of the beam which is accepted by the spectrometer. Observation of the development of the chirp in a mode-locked pulse train allows to determine the small incipient chirp of early pulses. A product, bandwidth times pulse duration, of 0.47 ± 0.03 is consistently observed for single pulses switched from a passively mode-locked Nd-glass system

    Radius dependent shift of surface plasmon frequency in large metallic nanospheres: theory and experiment

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    Theoretical description of oscillations of electron liquid in large metallic nanospheres (with radius of few tens nm) is formulated within random-phase-approximation semiclassical scheme. Spectrum of plasmons is determined including both surface and volume type excitations. It is demonstrated that only surface plasmons of dipole type can be excited by homogeneous dynamical electric field. The Lorentz friction due to irradiation of electro-magnetic wave by plasmon oscillations is analyzed with respect to the sphere dimension. The resulting shift of resonance frequency turns out to be strongly sensitive to the sphere radius. The form of e-m response of the system of metallic nanospheres embedded in the dielectric medium is found. The theoretical predictions are verified by a measurement of extinction of light due to plasmon excitations in nanosphere colloidal water solutions, for Au and Ag metallic components with radius from 10 to 75 nm. Theoretical predictions and experiments clearly agree in the positions of surface plasmon resonances and in an emergence of the first volume plasmon resonance in the e-m response of the system for limiting big nanosphere radii, when dipole approximation is not exact

    Surgeons produce innovative ideas which are frequently lost in the labyrinth of patents

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    Thoracic and cardiovascular surgery are innovative specialties that regularly recruit the latest technological developments into their armoury of devices and equipment. The introduction of new technology is dependant on patents; an important but single component of intellectual property. Patents enable the attribution of rights to concepts, ideas and inventions and this facilitates ownership, subsequent licensing and overall management of innovation and its outcome. It is not just thoracic and cardiovascular surgery, but the healthcare world in general that experiences ongoing technological evolution; so to remain contemporary, it is important that those in positions of responsibility are familiar with the relevant processes. This requires basic medico-legal knowledge and may be entwined with significant financial responsibility. Penetrating clinical, academic and industrial environments, informed awareness of patents also contributes to important leadership skills, encouraging the incorporation of innovation into the professional milieu. We aim to present through this manuscript an overview of these issues in order to promote awareness of patents within thoracic and cardiovascular surgery using a descriptive and practical approac

    Beryllium film deposition in cavity samples in remote areas of the JET divertor during the 2011-2012 ITER-like wall campaign

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    Beryllium film deposition was studied with cavity samples in remote areas of the inner and outer JET divertor and below divertor tile 5 during the 2011–2012 campaign with the ITER-like wall. Predominantly beryllium films were formed inside the cavities with some additional carbon, the ratio Be/C was > 2. These deposited layers had high D/(Be + C) ratios of about 0.3. The formation of these films is mainly due to sticking of beryllium-containing particles with low sticking coefficients < 0.5. The observed surface loss probabilities depend on the position in the divertor. The particles responsible for film deposition originated from the location of in the divertor strike points.EURATOM 63305

    Multiple glass transitions in star polymer mixtures: Insights from theory and simulations

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    The glass transition in binary mixtures of star polymers is studied by mode coupling theory and extensive molecular dynamics computer simulations. In particular, we have explored vitrification in the parameter space of size asymmetry δ\delta and concentration ρ2\rho_2 of the small star polymers at fixed concentration of the large ones. Depending on the choice of parameters, three different glassy states are identified: a single glass of big polymers at low δ\delta and low ρ2\rho_2, a double glass at high δ\delta and low ρ2\rho_2, and a novel double glass at high ρ2\rho_2 and high δ\delta which is characterized by a strong localization of the small particles. At low δ\delta and high ρ2\rho_2 there is a competition between vitrification and phase separation. Centered in the (δ,ρ2)(\delta, \rho_2)-plane, a liquid lake shows up revealing reentrant glass formation. We compare the behavior of the dynamical density correlators with the predictions of the theory and find remarkable agreement between the two.Comment: 15 figures, to be published in Macromolecule

    Pre-transplant CDKN2A expression in kidney biopsies predicts renal function and is a future component of donor scoring criteria

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    CDKN2A is a proven and validated biomarker of ageing which acts as an off switch for cell proliferation. We have demonstrated previously that CDKN2A is the most robust and the strongest pre-transplant predictor of post- transplant serum creatinine when compared to “Gold Standard” clinical factors, such as cold ischaemic time and donor chronological age. This report shows that CDKN2A is better than telomere length, the most celebrated biomarker of ageing, as a predictor of post-transplant renal function. It also shows that CDKN2A is as strong a determinant of post-transplant organ function when compared to extended criteria (ECD) kidneys. A multivariate analysis model was able to predict up to 27.1% of eGFR at one year post-transplant (p = 0.008). Significantly, CDKN2A was also able to strongly predict delayed graft function. A pre-transplant donor risk classification system based on CDKN2A and ECD criteria is shown to be feasible and commendable for implementation in the near future
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