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We show, for the first time, radio measurements of the depth of shower maximum (X_{max}) of air showers induced by cosmic rays that are compared to measurements of the established fluorescence method at the same location. Using measurements at the Pierre Auger Observatory we show full compatibility between our radio and the previously published fluorescence dataset, and between a subset of air showers observed simultaneously with both radio and fluorescence techniques, a measurement setup unique to the Pierre Auger Observatory. Furthermore, we show radio X_{max} resolution as a function of energy and demonstrate the ability to make competitive high-resolution X_{max} measurements with even a sparse radio array. With this, we show that the radio technique is capable of cosmic-ray mass composition studies, both at Auger and at other experiments.
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Instantons, which are nonperturbative solutions to Yang-Mills equations, provide a signal for the occurrence of quantum tunneling between distinct classes of vacua. They can give rise to decays of particles otherwise forbidden. Using data collected at the Pierre Auger Observatory, we search for signatures of such instanton-induced processes that would be suggestive of super-heavy particles decaying in the Galactic halo. These particles could have been produced during the post-inflationary epoch and match the relic abundance of dark matter inferred today. The nonobservation of the signatures searched for allows us to derive a bound on the reduced coupling constant of gauge interactions in the dark sector: α_{X}â²0.09, for 10^{9}â²M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}â³3×10^{13} GeV. In the context of dark matter production from gravitational interactions alone, we illustrate how these bounds are complementary to those obtained on the Hubble rate at the end of inflation from the nonobservation of tensor modes in the cosmological microwave background.
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We present the first measurement of the fluctuations in the number of muons in extensive air showers produced by ultrahigh energy cosmic rays. We find that the measured fluctuations are in good agreement with predictions from air shower simulations. This observation provides new insights into the origin of the previously reported deficit of muons in air shower simulations and constrains models of hadronic interactions at ultrahigh energies. Our measurement is compatible with the muon deficit originating from small deviations in the predictions from hadronic interaction models of particle production that accumulate as the showers develop.
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We report a measurement of the energy spectrum of cosmic rays above 2.5×10^{18} eV based on 215 030 events. New results are presented: at about 1.3×10^{19} eV, the spectral index changes from 2.51±0.03(stat)±0.05(syst) to 3.05±0.05(stat)±0.10(syst), evolving to 5.1±0.3(stat)±0.1(syst) beyond 5×10^{19} eV, while no significant dependence of spectral features on the declination is seen in the accessible range. These features of the spectrum can be reproduced in models with energy-dependent mass composition. The energy density in cosmic rays above 5×10^{18} eV is [5.66±0.03(stat)±1.40(syst)]×10^{53} erg Mpc^{-3}.
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We measure the energy emitted by extensive air showers in the form of radio emission in the frequency range from 30 to 80 MHz. Exploiting the accurate energy scale of the Pierre Auger Observatory, we obtain a radiation energy of 15.8±0.7(stat)±6.7(syst) MeV for cosmic rays with an energy of 1 EeV arriving perpendicularly to a geomagnetic field of 0.24 G, scaling quadratically with the cosmic-ray energy. A comparison with predictions from state-of-the-art first-principles calculations shows agreement with our measurement. The radiation energy provides direct access to the calorimetric energy in the electromagnetic cascade of extensive air showers. Comparison with our result thus allows the direct calibration of any cosmic-ray radio detector against the well-established energy scale of the Pierre Auger Observatory.
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Ultrahigh energy cosmic ray air showers probe particle physics at energies beyond the reach of accelerators. Here we introduce a new method to test hadronic interaction models without relying on the absolute energy calibration, and apply it to events with primary energy 6-16 EeV (E_{CM}=110-170 TeV), whose longitudinal development and lateral distribution were simultaneously measured by the Pierre Auger Observatory. The average hadronic shower is 1.33±0.16 (1.61±0.21) times larger than predicted using the leading LHC-tuned models EPOS-LHC (QGSJetII-04), with a corresponding excess of muons.
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We report a measurement of the proton-air cross section for particle production at the center-of-mass energy per nucleon of 57 TeV. This is derived from the distribution of the depths of shower maxima observed with the Pierre Auger Observatory: systematic uncertainties are studied in detail. Analyzing the tail of the distribution of the shower maxima, a proton-air cross section of [505±22(stat)(-36)(+28)(syst)] mb is found.
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In liquid argon time projection chambers exposed to neutrino beams and running on or near surface levels, cosmic muons, and other cosmic particles are incident on the detectors while a single neutrino-induced event is being recorded. In practice, this means that data from surface liquid argon time projection chambers will be dominated by cosmic particles, both as a source of event triggers and as the majority of the particle count in true neutrino-triggered events. In this work, we demonstrate a novel application of deep learning techniques to remove these background particles by applying deep learning on full detector images from the SBND detector, the near detector in the Fermilab Short-Baseline Neutrino Program. We use this technique to identify, on a pixel-by-pixel level, whether recorded activity originated from cosmic particles or neutrino interactions.
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We describe the measurement of the depth of maximum, X{max}, of the longitudinal development of air showers induced by cosmic rays. Almost 4000 events above 10;{18} eV observed by the fluorescence detector of the Pierre Auger Observatory in coincidence with at least one surface detector station are selected for the analysis. The average shower maximum was found to evolve with energy at a rate of (106{-21}{+35}) g/cm{2}/decade below 10{18.24+/-0.05} eV, and (24+/-3) g/cm{2}/decade above this energy. The measured shower-to-shower fluctuations decrease from about 55 to 26 g/cm{2}. The interpretation of these results in terms of the cosmic ray mass composition is briefly discussed.
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Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with [Formula: see text] eV by analyzing cosmic rays with energies above [Formula: see text] eV arriving within an angular separation of approximately 15[Formula: see text]. We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.
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Cardiopulmonary bypass with heparin-bonded circuits reduces systemic heparinization which is associated to a better clinical outcome in cardiac operations. In the present study, a novel biocompatible treatment, based on a phosphorylcholine coating without heparin, has been used to reduce systemic heparinization during cardiopulmonary bypass. Sixty patients underwent coronary revascularization with a fully phosphorylcholine-coated circuit. The circuit was entirely closed; suctions from the field were separated during the cardiopulmonary bypass time. A low systemic heparinization protocol based on half the loading dose of heparin (150 IU/kg) and a target activated clotting time of 320 seconds was applied. No thrombus formation inside the extracorporeal circulation circuit occurred; in-hospital mortality was absent. One patient (1.6%) had a postoperative myocardial infarction and 2 (3.3%) were surgically revised due to bleeding. Homologous blood transfusion rate was 11.6%, postoperative bleeding was 310 +/- 136 ml. If compared to patients treated with heparin-coated circuits and low systemic heparinization, these patients have better platelet count preservation and lower postoperative bleeding. The low thrombogenicity of phosphorylcholine-treated surfaces, despite the absence of surface-immobilized heparin, allows a safe reduction of systemic heparinization in the setting of an ECMO-like intraoperative cardiopulmonary - bypass. This intraoperative ECMO approach offers promising results in terms of clinical outcome after coronary revascularization operations.
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Anticoagulantes/administração & dosagem , Ponte Cardiopulmonar/instrumentação , Materiais Revestidos Biocompatíveis , Heparina/administração & dosagem , Fosforilcolina , Ponte Cardiopulmonar/métodos , Estudos de Casos e Controles , Protocolos Clínicos , Relação Dose-Resposta a Droga , Estudos de Viabilidade , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Avaliação de Resultados em Cuidados de Saúde , Fatores de Tempo , Tempo de Coagulação do Sangue TotalRESUMO
BACKGROUND: The aim of this study was to assess the ability of clinical and instrumental features to identify patients with left main coronary artery disease (LMCD) compared with a three-vessel coronary artery disease group. METHODS: A cohort of 70 patients with LMCD was matched with another one of 66 patients with three-vessel disease. A history of angina before angiography was similar in both groups; the higher degrees of stable angina and the forms of unstable angina were moderately prevalent in the group with LMCD. RESULTS: In the last subgroup a significantly reduced incidence of previous acute myocardial infarction (AMI) was observed (p < 0.05). The resting electrocardiogram (ECG) showed higher incidence of atrial fibrillation (fa) and left bundle branch block (BBS) in the subjects with LMCD, with a statistic value (p < 0.05). The exercise test performed by a lot of patients appeared equally positive for inducible ischemia in the 2 groups. Significantly higher exercise peak load was achieved by the patients with three-vessel disease (p < 0.05). The coronary angiography showed a prevalence of right dominant circulation in the 2 groups; significantly the collateral circulation was more represented in the subjects with three-vessel disease (p < 0.05). Most patients with LMCD underwent a bypass coronary artery graft surgery (CABG surgery) more frequently than the ones with three-vessel disease (p < 0.01). In the former group the cardiovascular mortality within an average 2-year follow-up proved higher as to the latter group even if without statistic significance. CONCLUSIONS: Nevertheless this retrospective study showed some limitations. Particularly the incidence of clinical and instrumental variables and their capacity to differentiate LMCD patients from those with three-vessel disease were not demonstrated.
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Doença das Coronárias/diagnóstico por imagem , Infarto do Miocárdio/diagnóstico por imagem , Revascularização Miocárdica , Doença Aguda , Angiografia Coronária , Doença das Coronárias/cirurgia , Feminino , Humanos , Masculino , Infarto do Miocárdio/cirurgia , Estudos RetrospectivosRESUMO
BACKGROUND: The aim of this study was to determine the role of the ST segment elevation resolution > 50% between the ECG before and 2 hours after thrombolytic therapy as a predictor of acute myocardial infarction (AMI)-related artery patency, assessed by a coronary angiography performed 1 month after AMI. MATERIALS AND METHODS: This study enrolled 95 patients, 75 men and 20 women, 58 years mean aged, admitted to the coronary care unit with diagnosis of AMI. Patients were treated with thrombolysis within 6 hours from the onset of chest pain, according to the GUSTO trial. RESULTS: The findings showed a significant prevalence of ST segment elevation resolution > 50% in inferior AMI (p < 0.01). It has been observed that the ST segment resolution is correlated with lower (p < 0.01) and earlier (p < 0.05) peak in serum creatinekinase (CK) and CK MB release and with less damage of left ventricular ejection fraction assessed by ventriculography (p < 0.01). All these findings indicated a lower extensive myocardial damage. Patients with ST segment resolution presented a prevalence of one or two-coronary vessel disease, with an infarct-related vessel narrowing like that observed in the other patients without ST resolution. Nevertheless a TIMI grade 2 or 3 flow was observed more frequently, but not significantly, in the subjects with ST resolution; a significant prevalence was limited to TIMI 3 grade flow (p < 0.05). In the present study ST segment elevation resolution > 50% represented a highly sensitive and a poor specific predictor of vessel patency in inferior AMI, but with a poor sensitivity and specificity in anterior AMI. CONCLUSIONS: Personal experience suggested that the thrombolytic therapy has a less favourable effect on the artery patency assessed 1 month after AMI, rather than in the acute phase as reported in previous studies. Dynamic changes of flow or a following worsening in atherosclerotic plaque could be probably responsible of reocclusion of an initially reperfused coronary artery.
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Eletrocardiografia , Infarto do Miocárdio/diagnóstico , Reperfusão Miocárdica/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Infarto do Miocárdio/terapia , Terapia Trombolítica , Fatores de TempoRESUMO
Bacterial endocarditis in pregnancy shows a low incidence; it is often associated with a prior history of rheumatic or congenital heart disease. In the large part of reports the illness tends to run a subacute course and to recognize a major frequency in the third trimester of pregnancy. We presented the case of a 29 year-old woman with mitral and aortic bacterial endocarditis. Transthoracic echocardiography performed one week after spontaneous delivery suggested valve vegetations. Antibiotic therapy turned out to be partially successful, in fact cerebral embolizations subsequently occurred. Conservative surgery appeared to be favourable and the patient shows a satisfactory present clinical state.
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Endocardite Bacteriana/diagnóstico por imagem , Complicações Cardiovasculares na Gravidez/diagnóstico por imagem , Complicações Infecciosas na Gravidez/diagnóstico por imagem , Transtornos Puerperais/diagnóstico por imagem , Adulto , Antibacterianos/uso terapêutico , Ecocardiografia/métodos , Endocardite Bacteriana/tratamento farmacológico , Endocardite Bacteriana/epidemiologia , Feminino , Humanos , Incidência , Insuficiência da Valva Mitral/diagnóstico por imagem , Gravidez , Complicações Cardiovasculares na Gravidez/tratamento farmacológico , Complicações Cardiovasculares na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/tratamento farmacológico , Complicações Infecciosas na Gravidez/epidemiologia , Complicações Infecciosas na Gravidez/microbiologia , Transtornos Puerperais/tratamento farmacológico , Resultado do TratamentoRESUMO
We describe the case of a 73-year-old man, admitted after several days of moderate dyspnea, followed by sincopal episode. Transesophageal echocardiography clearly demonstrated a high resolution image indicating thromboembolus of the proximal right main pulmonary artery. The patient's clinical conditions were moderately impaired; a treatment with heparin followed by warfarin was started. At 15 and 30 days interval, TEE controls were performed, showing an incomplete but evident resolution of pulmonary thromboembolism, associated to an improvement of clinical ECG and scintigraphic parameters. Our TEE observation, in accordance with the small number of similar observations reported in literature, showed a clear direct visualization with high resolutive diagnostic possibilities for pulmonary thromboembolism; successful resolution was confirmed by repeated TEE studies.
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Ecocardiografia Transesofagiana , Embolia Pulmonar/diagnóstico por imagem , Idoso , Humanos , MasculinoRESUMO
The authors discuss trends in return migration in Italy, with a focus on regional differences. "On a regional level, the effects of return migration are very much connected with socio-economic structure. Only highly developed and autonomous regions can absorb productive investments and changes brought about by return migration. Several southern regions--especially those with greater migration experience--have shown in the last decades a very poor socio-economic development." The study is concerned with both internal and international migration. (SUMMARY IN ENG AND FRE)
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Economia , Emigração e Imigração , Geografia , Dinâmica Populacional , Mudança Social , Fatores Socioeconômicos , Demografia , Países Desenvolvidos , Europa (Continente) , Itália , PopulaçãoRESUMO
PIP: The authors examine characteristics of female migration from Latin America to Italy. Aspects considered include country of origin, fertility behavior, age, employment status, household characteristics, and marriage patterns.^ieng
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Distribuição por Idade , Emigração e Imigração , Emprego , Características da Família , Casamento , Comportamento Sexual , Fatores Etários , Demografia , Países Desenvolvidos , Países em Desenvolvimento , Economia , Europa (Continente) , Fertilidade , Itália , América Latina , População , Características da População , Dinâmica Populacional , Classe Social , Fatores SocioeconômicosAssuntos
Emigração e Imigração/tendências , Adolescente , Adulto , África/etnologia , Idoso , Ásia/etnologia , Criança , Pré-Escolar , Emigração e Imigração/estatística & dados numéricos , Europa (Continente)/etnologia , Feminino , Humanos , Lactente , Recém-Nascido , Itália , Masculino , Pessoa de Meia-Idade , América do Norte/etnologia , Ilhas do Pacífico/etnologia , América do Sul/etnologia , Migrantes/estatística & dados numéricosRESUMO
"After having examined the relations between the partial net migration and the corresponding total net migration, an attempt is made to identify some indicators...of inter-regional mobility, considering the size of the total net migration in relation to all the net migrations with other territorial units. Attention is particularly focused on two indicators: the index of net regional migratory interchange, and the index of net total migratory interchange...." Data are for regions in Italy during the period 1955-1989. (SUMMARY IN ENG AND FRE)