Institution
University of Palermo
Education•Palermo, Italy•
About: University of Palermo is a education organization based out in Palermo, Italy. It is known for research contribution in the topics: Population & Cancer. The organization has 15621 authors who have published 40250 publications receiving 964384 citations. The organization is also known as: Università degli Studi di Palermo & Universita degli Studi di Palermo.
Topics: Population, Cancer, Catalysis, Diabetes mellitus, Volcano
Papers published on a yearly basis
Papers
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TL;DR: The average lifetime of the metastable state is greater than the time obtained in the absence of additive white noise and the system investigated exhibits a maximum of the lifetime as a function of the fluctuation rate of the potential.
Abstract: We derive general equations for the nonlinear relaxation time of Brownian diffusion in randomly switching potential with a sink For piece-wise linear dichotomously fluctuating potential with metastable state, we obtain the exact average lifetime as a function of the potential parameters and the noise intensity Our result is valid for arbitrary white noise intensity and for arbitrary fluctuation rate of the potential We find noise enhanced stability phenomenon in the system investigated: The average lifetime of the metastable state is greater than the time obtained in the absence of additive white noise We obtain the parameter region of the fluctuating potential where the effect can be observed The system investigated also exhibits a maximum of the lifetime as a function of the fluctuation rate of the potential
163 citations
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INAF1, Spanish National Research Council2, National Institute for Space Research3, University of Leicester4, Polish Academy of Sciences5, University of Helsinki6, Roma Tre University7, Royal Institute of Technology8, Stockholm University9, University of Oulu10, University of Valencia11, University of Tübingen12, Max Planck Society13, Marshall Space Flight Center14, Alenia Aeronautica15, University of Pisa16, University of Cagliari17, University of Palermo18, Academy of Sciences of the Czech Republic19, University of Birmingham20, University of Cambridge21, Tsinghua University22, University of Iowa23, Cornell University24, Centre national de la recherche scientifique25, University of Wrocław26, Moscow Institute of Physics and Technology27, Russian Academy of Sciences28, Harvard University29, Georgia Institute of Technology30, University College London31
TL;DR: The X-ray Imaging Polarimetry Explorer (XIPE) as mentioned in this paper was proposed in 2012 to the first ESA call for a small mission with a launch in 2017, but the proposal was, unfortunately, not selected.
Abstract: X-ray polarimetry, sometimes alone, and sometimes coupled to spectral and temporal variability measurements and to imaging, allows a wealth of physical phenomena in astrophysics to be studied. X-ray polarimetry investigates the acceleration process, for example, including those typical of magnetic reconnection in solar flares, but also emission in the strong magnetic fields of neutron stars and white dwarfs. It detects scattering in asymmetric structures such as accretion disks and columns, and in the so-called molecular torus and ionization cones. In addition, it allows fundamental physics in regimes of gravity and of magnetic field intensity not accessible to experiments on the Earth to be probed. Finally, models that describe fundamental interactions (e.g. quantum gravity and the extension of the Standard Model) can be tested. We describe in this paper the X-ray Imaging Polarimetry Explorer (XIPE), proposed in June 2012 to the first ESA call for a small mission with a launch in 2017. The proposal was, unfortunately, not selected. To be compliant with this schedule, we designed the payload mostly with existing items. The XIPE proposal takes advantage of the completed phase A of POLARIX for an ASI small mission program that was cancelled, but is different in many aspects: the detectors, the presence of a solar flare polarimeter and photometer and the use of a light platform derived by a mass production for a cluster of satellites. XIPE is composed of two out of the three existing JET-X telescopes with two Gas Pixel Detectors (GPD) filled with a He-DME mixture at their focus. Two additional GPDs filled with a 3-bar Ar-DME mixture always face the Sun to detect polarization from solar flares. The Minimum Detectable Polarization of a 1 mCrab source reaches 14 % in the 2–10 keV band in 105 s for pointed observations, and 0.6 % for an X10 class solar flare in the 15–35 keV energy band. The imaging capability is 24 arcsec Half Energy Width (HEW) in a Field of View of 14.7 arcmin × 14.7 arcmin. The spectral resolution is 20 % at 6 keV and the time resolution is 8 μs. The imaging capabilities of the JET-X optics and of the GPD have been demonstrated by a recent calibration campaign at PANTER X-ray test facility of the Max-Planck-Institut fur extraterrestrische Physik (MPE, Germany). XIPE takes advantage of a low-earth equatorial orbit with Malindi as down-link station and of a Mission Operation Center (MOC) at INPE (Brazil). The data policy is organized with a Core Program that comprises three months of Science Verification Phase and 25 % of net observing time in the following 2 years. A competitive Guest Observer program covers the remaining 75 % of the net observing time.
162 citations
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TL;DR: The influence of the calculation method in mimicking experimental 13C NMR chemical shifts of 15 low‐polarity natural products singularly containing 10–20 carbon atoms was investigated by employing different quantum chemistry approaches and basis sets, both in the preliminary geometry optimizations and in the following single‐point 13C GIAO calculations of the N MR chemical shifts.
Abstract: The influence of the calculation method in mimicking experimental 13C NMR chemical shifts of 15 low-polarity natural products singularly containing 10–20 carbon atoms was investigated by employing different quantum chemistry approaches and basis sets, both in the preliminary geometry optimizations and in the following single-point 13C GIAO calculations of the NMR chemical shifts. The geometries of the involved species were optimized at the PM3, HF, B3LYP and mPW1PW91 levels whereas the 13C NMR parameters were determined at the HF, B3LYP and mPW1PW91 levels. Different combinations of basis sets were also tested. The consistency and efficiency of the considered combinations of geometry optimizations and GIAO 13C NMR calculations were thoroughly checked by the analysis of statistical parameters concerning computed and experimental 13C NMR chemical shift values. Copyright © 2004 John Wiley & Sons, Ltd.
162 citations
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TL;DR: The actual frequency and intensity of symptoms in a non-selected home care population with advanced cancer is clarified, with the peak of opioid consumption and symptom frequency and severity found at K40.
162 citations
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TL;DR: In this paper, the concept of a @W-distance on a complete partially ordered G-metric space is considered and some fixed point theorems are proved.
162 citations
Authors
Showing all 15895 results
Name | H-index | Papers | Citations |
---|---|---|---|
Robin M. Murray | 171 | 1539 | 116362 |
Frede Blaabjerg | 147 | 2161 | 112017 |
Jean Bousquet | 145 | 1288 | 96769 |
Zhanhu Guo | 128 | 886 | 53378 |
Jean Ballet | 115 | 263 | 46301 |
Antonio Facchetti | 111 | 602 | 51885 |
Michele Pagano | 97 | 306 | 42211 |
Frank Z. Stanczyk | 93 | 620 | 30244 |
Eleonora Troja | 91 | 271 | 30873 |
Francesco Sciortino | 90 | 536 | 28956 |
Zev Rosenwaks | 89 | 772 | 32039 |
Antonio Russo | 88 | 934 | 34563 |
Carlo Salvarani | 88 | 730 | 31699 |
Giuseppe Basso | 87 | 643 | 33320 |
Antonio Craxì | 86 | 659 | 39463 |