| 1. |
- Feroci, M., et al.
(författare)
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The Large Observatory for X-ray Timing (LOFT)
- 2012
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Ingår i: Experimental Astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 34:2, s. 415-444
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Tidskriftsartikel (refereegranskat)abstract
- High-time-resolution X-ray observations of compact objects provide direct access to strong-field gravity, to the equation of state of ultradense matter and to black hole masses and spins. A 10 m(2)-class instrument in combination with good spectral resolution is required to exploit the relevant diagnostics and answer two of the fundamental questions of the European Space Agency (ESA) Cosmic Vision Theme "Matter under extreme conditions", namely: does matter orbiting close to the event horizon follow the predictions of general relativity? What is the equation of state of matter in neutron stars? The Large Observatory For X-ray Timing (LOFT), selected by ESA as one of the four Cosmic Vision M3 candidate missions to undergo an assessment phase, will revolutionise the study of collapsed objects in our galaxy and of the brightest supermassive black holes in active galactic nuclei. Thanks to an innovative design and the development of large-area monolithic silicon drift detectors, the Large Area Detector (LAD) on board LOFT will achieve an effective area of similar to 12 m(2) (more than an order of magnitude larger than any spaceborne predecessor) in the 2-30 keV range (up to 50 keV in expanded mode), yet still fits a conventional platform and small/medium-class launcher. With this large area and a spectral resolution of < 260 eV, LOFT will yield unprecedented information on strongly curved spacetimes and matter under extreme conditions of pressure and magnetic field strength.
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| 2. |
- Pellizzoni, A., et al.
(författare)
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Detection of Gamma-Ray Emission from the Vela Pulsar Wind Nebula with AGILE
- 2010
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Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 327:5966, s. 663-665
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Tidskriftsartikel (refereegranskat)abstract
- Pulsars are known to power winds of relativistic particles that can produce bright nebulae by interacting with the surrounding medium. These pulsar wind nebulae are observed by their radio, optical, and x-ray emissions, and in some cases also at TeV (teraelectron volt) energies, but the lack of information in the gamma-ray band precludes drawing a comprehensive multiwavelength picture of their phenomenology and emission mechanisms. Using data from the AGILE satellite, we detected the Vela pulsar wind nebula in the energy range from 100 MeV to 3 GeV. This result constrains the particle population responsible for the GeV emission and establishes a class of gamma-ray emitters that could account for a fraction of the unidentified galactic gamma-ray sources.
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| 3. |
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| 4. |
- Duran, Mauricio A. Caceres, et al.
(författare)
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Terrestrial Network-Based Positioning and Navigation
- 2012
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Ingår i: Satellite and Terrestrial Radio Positioning Techniques, Davide Dardari, Emanuela Falletti, and Marco Luise, editors. Oxford, Academic Press. - 9780123820846 ; , s. 75-153
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 5. |
- Hellström, Per M., et al.
(författare)
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Receptor-mediated inhibition of small bowel migrating complex by GLP-1 analog ROSE-010 delivered via pulmonary and systemic routes in the conscious rat
- 2012
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Ingår i: Regulatory Peptides. - : Elsevier BV. - 0167-0115 .- 1873-1686. ; 179:1-3, s. 71-76
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Tidskriftsartikel (refereegranskat)abstract
- Background: ROSE-010, a Glucagon-Like Peptide-1 (GLP-1) analog, reduces gastrointestinal motility and relieves acute pain in patients with irritable bowel syndrome (IBS). The rat small bowel migrating myoelectric complex (MMC) is a reliable model of pharmacological effects on gastrointestinal motility. Accordingly, we investigated whether ROSE-010 works through GLP-1 receptors in gut musculature and its effectiveness when administered by pulmonary inhalation. Materials and methods: Rats were implanted with bipolar electrodes at 5, 15 and 25 cm distal to pylorus and myoelectric activity was recorded. First, intravenous or subcutaneous injections of ROSE-010 or GLP-1 (1, 10, 100 mu g/kg) with or without the GLP-1 receptor blocker exendin(9-39)amide (300 mu g/kg.h), were studied. Second, ROSE-010 (100, 200 mu g/kg) Technosphere (R) powder was studied by inhalation. Results: The baseline MMC cycle length was 17.5 +/- 0.8 min. GLP-1 and ROSE-010. administered intravenously or subcutaneously, significantly inhibited myoelectric activity and prolonged MMC cycling; 100 mu g/kg completely inhibited spiking activity for 49.1 +/- 4.2 and 73.3 +/- 7.7 min, while the MMC cycle length increased to 131.1 +/- 11.4 and 149.3 +/- 15.5 min, respectively. Effects of both drugs were inhibited by exendin(9-39) amide. Insufflation of ROSE-010 (100, 200 mu g/kg) powder formulation totally inhibited myoelectric spiking for 52.6 +/- 5.8 and 70.1 +/- 5.4 min, and increased MMC cycle length to 102.6 +/- 18.3 and 105.9 +/- 9.5 min, respectively. Conclusions: Pulmonary delivery of ROSE-010 inhibits gut motility through the GLP-1R similar to natural GLP-1. ROSE-010 causes receptor-mediated inhibition of MMC comparable to that of intravenous or subcutaneous administration. This suggests that ROSE-010 administered as a Technosphere (R) inhalation powder has potential in IBS pain management and treatment.
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| 6. |
- Proletov, Ian, et al.
(författare)
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Primary and secondary glomerulonephritides 1.
- 2014
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Ingår i: Nephrology, dialysis, transplantation : official publication of the European Dialysis and Transplant Association - European Renal Association. - : Oxford University Press (OUP). - 1460-2385. ; 29 Suppl 3:May, s. 186-200
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Tidskriftsartikel (refereegranskat)
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| 7. |
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| 8. |
- Martinelli, E, et al.
(författare)
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Odor Processing with an experimental model of Olfactory epithelium and bulb
- 2011
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Ingår i: Chemical Senses. - : Oxford University Press. - 0379-864X .- 1464-3553. ; 36:1, s. E4-E4
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Artificial olfaction was introduced as a model tool to investigateolfaction properties [1]. Nonetheless, the only analogy between the natural and the artificial system lies just in the selectivity proper- ties of the receptors. The implementation of more sophisticated fea- tures such as the large number of receptors and the glomerular layer have been hampered by technical difficulties related to the manage- ment of large numbers of simultaneous signals.As demonstrated in the past, optical imaging is a read-out tech- nique for sensors development that can provide large sensor arrays [2]. On that basis, we recently introduced an artificial olfaction sys- tem based on the imaging of a continuous layer of chemical indi- cators [3]. In this situation an image sensor provides a segmentation of the whole sensing layer in a number of elementary units corre- sponding to the pixels of the image. Eventually, since it is possible to evaluate the optical properties of every single pixel, each pixel of the image may correspond to an individual sensor. In this regard, even low-resolution images may easily result in thousands of independ- ent sensing units.In our system a collection of arbitrarily shaped regions of color indicators is illuminated by a controlled light source; the optical characteristics of each pixel of the image are measured by a camera yielding the light intensities in the three channels red, green, and blue. The combination of illumination sequence and cameraread-out results in a fingerprint encoding the optical properties of the sensing layer portioned in image pixels. Even a simple clas- sification of these fingerprints assigns each pixel to a class, and each class contains pixels carrying the same color indicator. This behav- ior resembles the association between ORNs carrying the same chemical receptors into the same glomerulus [4]. On the basis of this analogy it is straightforward to describe the layer of indicators as an artificial epithelium, pixels of the image as artificial olfactory neu- rons, and the classes provided by the classifier as an abstract rep- resentation of artificial glomeruli.This system thus allows the generation of a complex model of olfaction, including glomerular compartmentalization [5], which is then applied to data generated by the exposure to pure and mixed gases. Results show that such a model enhances the discrimination of pure and mixed odors. Eventually, such a platform, apart from evidencing the similarities between natural and artificial olfactory systems, is also proposed as a practical tool to test olfactory models.1. K. Persaud and G. Dodds, Nature 299 (1982) 3522. Dickinson et al., Nature 382 (1996) 6973. C. Di Natale et al., PLoS ONE 3 (2008) 31394. P. Mombaerts, Annu Rev Neurosci 22 (1999) 4875. D. Schild and H. Riedel, Biophysical Journal, 61 (1992) 704
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| 9. |
- Soffitta, Paolo, et al.
(författare)
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XIPE : the X-ray imaging polarimetry explorer
- 2013
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Ingår i: Experimental astronomy. - : Springer Science and Business Media LLC. - 0922-6435 .- 1572-9508. ; 36:3, s. 523-567
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Tidskriftsartikel (refereegranskat)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 10(5) 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 x 14.7 arcmin. The spectral resolution is 20 % at 6 keV and the time resolution is 8 mu s. 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.
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