177,082 research outputs found
Magnetic behaviour and transport properties of Hg-1201 prepared by vapour-solid reaction.
No full textDetection of paraneoplastic anti-neuronal-specific antibodies: comparison of different immunohistochemical techniques.
No full textNew parametric transducer for resonant detectors: Advances and room temperature test
No full textWe are developing a prototype of cryogenic parametric converter transducer operating at 5 GHz, for the upgrade of the ROG Collaboration resonant G. W. antennas. This device is built on the experience of the Niobe detector (D. G. Blair et al.), with substantial modifications that should let us achieve better stability and sensitivity. The prototype uses as parametric converter a superconducting coaxial cavity with a 50 micron gap (Q 0 = 5 × 10 8 at 1.5K and 100μW RF power dissipation), and a contacless RF coupling for thermal insulation between the 2K stage and the ultra cryogenic (100mK) antenna. The coupler features a constant transmission loss of 0.2dB over a range of displacements of 5mm in x, y and z around the nominal operating position with a separation of 8mm between the two halves of the coupler. In this way the large, low frequency swings (0.5 and 17 Hz), of the 2 Tons antenna around its suspension point have no influence on the transducer performance. To test all the components of the transducer and the system performance, a room temperature prototype is installed on the TART (Test Antenna at Room Temperature) facility at the INFN labs. Using critical coupling for the RF cavity input coupler we manage to keep to a minimum the leakage of the drive signal to the first RF amplifier. In this way we avoid degradation of the RF amplifier noise figure (0.6 dB at room temperature) produced by the RF amplifier saturation Experimental results agree with the full analysis of the room temperature detector performances. © 2008 IOP Publishing Ltd
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Environmental benefits of a universal mobile charger and energy-aware survey on current products
No full textIntelec, The International Telecommunications Energy Conference 201
Supercurrent lengthscale in sintered YBCO and critical state model.
No full textMagnetization measurements on sintered YBa2Cu3O7−y in two geometries (slab and cylinder) show the coexistence of two transport mechanisms: intergranular and intragranular currents. Both mechanisms can be explained in the framework of the critical state model. Using a simple law for the critical current versus magnetic field dependence, it is possible to calculate the magnetization and the in-phase and out-of-phase AC susceptibility and the agreement with the experimental data is good. Magnetization measurements on tubular samples have been performed too; these measurements, together with χAC measurements allow to determine the dimensions of magnetized regions
Characterization of the superconducting transition of thin Ir films for TES
No full textWe are currently producing iridium based TESs for a wide variety of applications such as single photon detection of the visible and infrared light, X-ray spectroscopy and low energy nuclear beta and electron capture spectroscopy for neutrino mass search experiment. We present a study of the TES performance related to the superconductivity properties of the Ir film as function of the production processes, that depend on substrate type: Si or SiN, and of the operating electrical parameters. Moreover we developed a Finite Element model of thin superconducting film, by which we obtain qualitative agreement between experimental and simulated data. © 2009 IEEE
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Pulmonary toxicity of instilled cadmium-doped silica nanoparticles during acute and subacute stages in rats
No full textSilica nanoparticles (NPs) incorporating cadmium (Cd) have been developed for a range of potential application including drug delivery devices. Occupational Cd inhalation has been associated with emphysema, pulmonary fibrosis and lung tumours. Mechanistically, Cd
can induce oxidative stress and mediate cell-signalling pathways that are involved in inflammation.This in vivo study aimed at investigating pulmonary molecular effects of NPs doped with Cd (NP-Cd, 1 mg/animal) compared to soluble CdCl2 (400 mg/animal), in Sprague
Dawley rats treated intra-tracheally, 7 and 30 days after administration. NPs of silica containing Cd salt were prepared starting from commercial nano-size silica powder (HiSilTM T700 Degussa) with average pore size of 20 nm and surface area of 240 m2/g.
Toxicogenomic analysis was performed by the DNA microarray technology (using Agilent Whole Rat Genome Microarray 4x44K) to evaluate changes in gene expression of the entire genome. These findings indicate that the whole genome analysis may represent a valuable approach to assess the whole spectrum of biological responses to cadmium containing nanomaterials
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