Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 7 de 7
Filtrar
Mais filtros








Base de dados
Intervalo de ano de publicação
1.
Eur Phys J C Part Fields ; 83(6): 467, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37303462

RESUMO

The ICARUS collaboration employed the 760-ton T600 detector in a successful 3-year physics run at the underground LNGS laboratory, performing a sensitive search for LSND-like anomalous νe appearance in the CERN Neutrino to Gran Sasso beam, which contributed to the constraints on the allowed neutrino oscillation parameters to a narrow region around 1 eV2. After a significant overhaul at CERN, the T600 detector has been installed at Fermilab. In 2020 the cryogenic commissioning began with detector cool down, liquid argon filling and recirculation. ICARUS then started its operations collecting the first neutrino events from the booster neutrino beam (BNB) and the Neutrinos at the Main Injector (NuMI) beam off-axis, which were used to test the ICARUS event selection, reconstruction and analysis algorithms. ICARUS successfully completed its commissioning phase in June 2022. The first goal of the ICARUS data taking will be a study to either confirm or refute the claim by Neutrino-4 short-baseline reactor experiment. ICARUS will also perform measurement of neutrino cross sections with the NuMI beam and several Beyond Standard Model searches. After the first year of operations, ICARUS will search for evidence of sterile neutrinos jointly with the Short-Baseline Near Detector, within the Short-Baseline Neutrino program. In this paper, the main activities carried out during the overhauling and installation phases are highlighted. Preliminary technical results from the ICARUS commissioning data with the BNB and NuMI beams are presented both in terms of performance of all ICARUS subsystems and of capability to select and reconstruct neutrino events.

2.
Eur Phys J C Part Fields ; 78(12): 1006, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30872956

RESUMO

One of the main objectives of the ANTARES telescope is the search for point-like neutrino sources. Both the pointing accuracy and the angular resolution of the detector are important in this context and a reliable way to evaluate this performance is needed. In order to measure the pointing accuracy of the detector, one possibility is to study the shadow of the Moon, i.e. the deficit of the atmospheric muon flux from the direction of the Moon induced by the absorption of cosmic rays. Analysing the data taken between 2007 and 2016, the Moon shadow is observed with 3.5 σ statistical significance. The detector angular resolution for downward-going muons is 0 . 73 ∘ ± 0 . 14 ∘ . The resulting pointing performance is consistent with the expectations. An independent check of the telescope pointing accuracy is realised with the data collected by a shower array detector onboard of a ship temporarily moving around the ANTARES location.

3.
Eur Phys J C Part Fields ; 77(6): 419, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28775667

RESUMO

A novel algorithm to reconstruct neutrino-induced particle showers within the ANTARES neutrino telescope is presented. The method achieves a median angular resolution of [Formula: see text] for shower energies below 100 TeV. Applying this algorithm to 6 years of data taken with the ANTARES detector, 8 events with reconstructed shower energies above 10 TeV are observed. This is consistent with the expectation of about 5 events from atmospheric backgrounds, but also compatible with diffuse astrophysical flux measurements by the IceCube collaboration, from which 2-4 additional events are expected. A [Formula: see text] C.L. upper limit on the diffuse astrophysical neutrino flux with a value per neutrino flavour of [Formula: see text] is set, applicable to the energy range from 23 TeV to 7.8 PeV, assuming an unbroken [Formula: see text] spectrum and neutrino flavour equipartition at Earth.

4.
Sci Rep ; 7: 45517, 2017 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-28401960

RESUMO

Despite dedicated research has been carried out to adequately map the distribution of the sperm whale in the Mediterranean Sea, unlike other regions of the world, the species population status is still presently uncertain. The analysis of two years of continuous acoustic data provided by the ANTARES neutrino telescope revealed the year-round presence of sperm whales in the Ligurian Sea, probably associated with the availability of cephalopods in the region. The presence of the Ligurian Sea sperm whales was demonstrated through the real-time analysis of audio data streamed from a cabled-to-shore deep-sea observatory that allowed the hourly tracking of their long-range echolocation behaviour on the Internet. Interestingly, the same acoustic analysis indicated that the occurrence of surface shipping noise would apparently not condition the foraging behaviour of the sperm whale in the area, since shipping noise was almost always present when sperm whales were acoustically detected. The continuous presence of the sperm whale in the region confirms the ecological value of the Ligurian sea and the importance of ANTARES to help monitoring its ecosystems.

5.
Dig Liver Dis ; 37(12): 934-9, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-16243592

RESUMO

BACKGROUND: Although general practitioners play a critical role in the management of irritable bowel syndrome because they deal with the most patients, guidelines are developed mainly by specialists. AIMS: To evaluate the clinical features of irritable bowel patients and the general practitioners' approach to irritable bowel syndrome in Italy. SUBJECTS AND METHODS: A questionnaire focusing on the management of this syndrome was completed by 28 general practitioners. Clinical features and diagnostic and treatment measures taken in 229 patients were analysed. RESULTS: Only 35.7% of the general practitioners were familiar with the Rome II criteria. Changes in bowel habits and abdominal pain/discomfort were the most common symptoms. Constipation (74.2%) was more frequent as the main symptom than diarrhoea. Routine blood tests (76.4%) and abdominal ultrasound (42.2%) were requested more frequently than colonoscopy (31.1%). At least one specialist consultation was recommended in 63.3% of patients. Drugs (mainly antispasmodics) were prescribed more frequently for diarrhoea (91.4%) than for constipation (55.7%). CONCLUSIONS: General practitioners are little acquainted with the Rome II criteria. Diagnostic tests and specialist consultations are often recommended; antispasmodics are the most frequently prescribed drug. Guidelines should be developed together by general practitioners and gastroenterologists to effectively manage patients at a lower cost.


Assuntos
Síndrome do Intestino Irritável/diagnóstico , Síndrome do Intestino Irritável/terapia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Medicina de Família e Comunidade , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade , Inquéritos e Questionários
6.
Am J Respir Crit Care Med ; 155(2): 466-72, 1997 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-9032180

RESUMO

We have applied the technique of sputum induction by hypertonic saline in asthmatics and nonatopic control subjects to study an array of indices of airway inflammation believed to be relevant to asthma pathogenesis. Compatible with a central role for eosinophils and mast cells in asthma, sputum of asthmatic subjects contained increased numbers of eosinophils and levels of eosinophil cationic protein (ECP) and mast cell tryptase. Eosinophil numbers, and ECP and histamine levels correlated with the degree of methacholine airways responsiveness, and ECP, tryptase, and histamine correlated with raised concentrations of albumin. Using the micro-Boyden chamber technique eosinophil chemotactic activity was identified only in the sputum from asthmatics. The correlation between the raised levels of total IgA, IL-8/IgA complexes, and tryptase and the degree of sputum eosinophilia and ECP levels, suggests possible mechanisms for eosinophil chemotaxis and activation in asthma. Row cytometric analysis of sputum lymphocytes showed an increase in CD4+ T cells and T cells expressing intercellular adhesion molecule-1 (ICAM-1) in asthma which, together with the finding of raised levels of soluble ICAM-1 in the sputum, indicates upregulation of this adhesion molecule. Finally, the proportion of CD16+ natural killer (NK) cells was reduced in the sputum of asthmatics. These observations highlight the importance of the airway inflammation in causing asthma and further confirm the usefulness of sputum induction as a tool in asthma research.


Assuntos
Asma/metabolismo , Fatores Quimiotáticos de Eosinófilos/análise , Molécula 1 de Adesão Intercelular/análise , Escarro/química , Adulto , Quimases , Humanos , Mediadores da Inflamação/análise , Pessoa de Meia-Idade , Testes de Função Respiratória , Serina Endopeptidases/análise , Escarro/citologia , Triptases
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA