Focal Nodular Hyperplasia (FNH) is a hypervascular benign tumor that usually appears in young women. Its course is generally asymptomatic and diagnosis is often incidental. OBJECTIVE: We report a ...case of symptomatic FNH in a 33-year-old women, mimicking hepatic abscess. At clinical examination she referred prolonged fever and pain localized in right upper abdomen; 2 months earlier pelvic endometriosis was removed with surgical endoscopic treatment. METHODS: Triphasic helical CT scan, ultrasound examination+fine needle biopsy and echo-enhanced Doppler sonography (Levovist super(TM)) were performed. RESULTS: CT and Doppler sonography suggested FNH with central stellate scar in right hepatic lobe (7 cm). Cytological examination showed normal hepatic cells and granulocyte; Gram stain and culture were negative. Empiric antibiotic treatment with cefotaxime plus metronidazole was performed for 4 weeks with defervescence and decrease of abdominal pain. CONCLUSION: We suggest that in this case FNH played a critical role in secondary localization (presuppurative hepatic lesion) of an occult bacteriemia subsequent to pelvic surgery. Clinical presentation, differential diagnosis and management is discussed and the role of echo-enhanced Doppler sonography in the diagnosis of FNH is stressed.
In a prospective, controlled, single-blind study the efficacy of teicoplanin versus cefamandole in preventing infections in total hip replacement was investigated in 496 consecutive patients. A ...single intravenous dose of teicoplanin (400 mg) was as effective as two intravenous doses of cefamandole (2 g before and 1 g after surgery). No major complications were observed in either group. Infective wound complications were observed only in the cefamandole group. These infections, although not dangerous for the patients, required supplementary antibiotic treatment in all cases. Teicoplanin is a reasonable choice as a prophylactic agent in orthopaedic surgery when a high risk of infection due to staphylococci is present.
Borexino is a 300 ton sub-MeV liquid scintillator solar neutrino detector which has been running at the Laboratori Nazionali del Gran Sasso (Italy) since 2007. Thanks to its unprecedented ...radio-purity, it was able to measure the flux of 7Be, 8B, pp, and pep solar neutrinos and to detect geo-neutrinos. A reliable simulation of the detector is an invaluable tool for all Borexino physics analyses. The simulation accounts for the energy loss of particles in all the detector components, the generation of the scintillation photons, their propagation within the liquid scintillator volume, and a detailed simulation of the electronics chain. A novel efficient method for simulating the external background which survives the Borexino passive shield was developed. This technique allows to reliably predict the effect of the contamination in the peripheral construction materials. The techniques developed to simulate the Borexino detector and their level of refinement are of possible interest to the neutrino and dark matter communities, especially for current and future large-volume liquid scintillator experiments.
The Borexino experiment, located in the Laboratori Nazionali del Gran Sasso in Italy and widely known for its rich Solar Neutrino physics program, has recently celebrated the 10 years of data taking. ...Among the achievements of the Borexino experiment solar program are: a precision measurement of 7Be neutrino flux with uncertainty of 3%, limit on its day/night asymmetry, first spectral measurement of pp-neutrinos, first evidence of monoenergetic pep neutrinos at 5 sigma, 8B neutrinos detection with the lowest visible energy threshold of 3 MeV, observation of season modulation of the 7Be solar neutrino rate at 3.8 sigma and the best current limit on CNO neutrino flux. Borexino is now in its high-purity Phase II data taking, thanks to intense purification campaigns of scintillator in 2010-11 that were very successful in further reducing the already low backgrounds. The advanced tecniques of data analysis were improved, allowing to maximize the signal/noise ratio. The detector was thermally insulated in order to improve the fluid stability. As an outcome, quality of the data has significantly increased leading to new levels of sensitivity to all solar neutrino fluxes. This allows a more sensitive probe for CNO neutrinos relevant to the solar metallicity problem.
We present the evidence for the seasonal modulation of the 7Be neutrino interaction rate with the Borexino detector at the Laboratori Nazionali del Gran Sasso in Italy. The period, amplitude, and ...phase of the observed time evolution of the signal are consistent with its solar origin, and the absence of an annual modulation is rejected at 99.99% C.L. The data are analyzed using three methods: the analytical fit to event rate, the Lomb-Scargle and the Empirical Mode Decomposition techniques, which all yield results in excellent agreement.
Plastic scintillators have become increasingly important in particle physics for time-of-flight and calorimetry measurements. Their light yield and the possibility of customizing their geometry make ...them also attractive for the construction of active vetoes in rare event physics experiments. For this purpose, some commercial plastic scintillators (purchased from Eljen Technology) were tested in cryogenic environments (liquid nitrogen and liquid helium). Their relative light yield was estimated by comparing the data acquired at room temperature with those acquired at cryogenic temperatures. Finally, estimates of the variation of the light yield at cryogenic temperatures were obtained.
Solar neutrino physics with Borexino Andrea Pocar, M. Agostini, K. Altenmüller, S. Appel, V. Atroshchenko, Z. Bagdasarian, D. Basilico, G. Bellini, J. Benziger, G. Bonfini, D. Bravo, B. Caccianiga, F. Calaprice, A. Caminata, L. Cappelli, S. Caprioli, M. Carlini, P. Cavalcante, F. Cavanna, A. Chepurnov, K. Choi, L. Collica, D. D’Angelo, S. Davini, A. Derbin, X. F. Ding, A. Di Ludovico, L. Di Noto, I. Drachnev, K. Fomenko, A. Formozov, D. Franco, F. Gabriele, C. Galbiati, M. Gschwender, C. Ghiano, M. Giammarchi, A. Goretti, M. Gromov, D. Guffanti, T. Houdy, E. Hungerford, Aldo Ianni, Andrea Ianni, A. Jany, D. Jeschke, S. Kumaran, V. Kobychev, G. Korga, T. Lachenmaier, M. Laubenstein, E. Litvinovich, P. Lombardi, L. Ludhova, G. Lukyanchenko, L. Lukyanchenko, I. Machulin, G. Manuzio, S. Marcocci, J. Maricic, J. Martyn, E. Meroni, M. Meyer, L. Miramonti, M. Misiaszek, V. Muratova, B. Neumair, M. Nieslony, L. Oberauer, V. Orekhov, F. Ortica, M. Pallavicini, L. Papp, Ö. Penek, L. Pietrofaccia, N. Pilipenko, A. Porcelli, G. Raikov, G. Ranucci, A. Razeto, A. Re, M. Redchuk, A. Romani, N. Rossi, S. Rottenanger, S. Schönert, D. Semenov, M. Skorokhvatov, O. Smirnov, A. Sotnikov, L. F. F. Stokes, Y. Suvorov , R. Tartaglia, G. Testera, J. Thurn, E. Unzhakov, A. Vishneva, R. B. Vogelaar, F. von Feilitzsch, S. Weinz, M. Wojcik, M. Wurm, O. Zaimidoroga, S. Zavatarelli, K. Zuber, G. Zuzel
SciPost physics proceedings,
02/2019
1
Journal Article
Recenzirano
Odprti dostop
We present the most recent solar neutrino results from the Borexino experiment at the Gran Sasso underground laboratory. In particular, refined measurements of all neutrinos produced in the {\it pp} ...fusion chain have been made. It is the first time that the same detector measures the entire range of solar neutrinos at once. These new data weakly favor a high-metallicity Sun. Prospects for measuring CNO solar neutrinos are also discussed.
Borexino is a liquid scintillator detector sited underground in the Laboratori Nazionali del Gran Sasso (Italy). Its physics program, until the end of this year, is focussed on the study of solar ...neutrinos, in particular from the Beryllium, pp, pep and CNO fusion reactions. Knowing the reaction chains in the sun provides insights towards physics disciplines such as astrophysics (star physics, star formation, etc.), astroparticle and particle physics. Phase II started in 2011 and its aim is to improve the phase I results, in particular the measurements of the neutrino fluxes from the pep and CNO processes. By the end of this year, data taking from the sun will be over and a new project is scheduled to launch: Short distance Oscillation with boreXino (SOX), which uses a Cerium source for neutrinos (100÷150 kCi of activity) and aims to confirm or rule out the presence of sterile neutrinos. This particle is hypothesised to justify the reactor, Gallium and LSND anomalies found and can reject extensions to the standard model. The work presented is a summary of the solar neutrino results achieved so far, which lead not only to a precise study of the processes in the sun, but also to more Standard Model oriented measurements (such as the stability of the charge, i.e. the life time of the electron). Furthermore, the perspectives of the SOX program are discussed showing the experiment sensitivity to a fourth neutrino state covering almost entirely 3σ of the preferred region of the anomalous neutrino experiments, and additional applications of the detector such as the study of geo-neutrinos.