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1.
Phys Rev Lett ; 132(2): 021001, 2024 Jan 12.
Article in English | MEDLINE | ID: mdl-38277596

ABSTRACT

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.

2.
Phys Rev Lett ; 130(6): 061001, 2023 Feb 10.
Article in English | MEDLINE | ID: mdl-36827568

ABSTRACT

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}≲0.09, for 10^{9}≲M_{X}/GeV<10^{19}. Conversely, we obtain that, for instance, a reduced coupling constant α_{X}=0.09 excludes masses M_{X}≳3×10^{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.

3.
Front Artif Intell ; 4: 649917, 2021.
Article in English | MEDLINE | ID: mdl-34505055

ABSTRACT

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.

4.
Phys Rev Lett ; 126(15): 152002, 2021 Apr 16.
Article in English | MEDLINE | ID: mdl-33929235

ABSTRACT

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.

5.
Phys Rev Lett ; 125(12): 121106, 2020 Sep 18.
Article in English | MEDLINE | ID: mdl-33016715

ABSTRACT

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}.

6.
Phys Rev Lett ; 117(19): 192001, 2016 Nov 04.
Article in English | MEDLINE | ID: mdl-27858429

ABSTRACT

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.

7.
Phys Rev Lett ; 116(24): 241101, 2016 Jun 17.
Article in English | MEDLINE | ID: mdl-27367377

ABSTRACT

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.

8.
Eur Phys J C Part Fields ; 75(6): 269, 2015.
Article in English | MEDLINE | ID: mdl-26120280

ABSTRACT

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.

9.
Phys Rev Lett ; 109(6): 062002, 2012 Aug 10.
Article in English | MEDLINE | ID: mdl-23006259

ABSTRACT

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.

10.
Phys Rev Lett ; 104(9): 091101, 2010 Mar 05.
Article in English | MEDLINE | ID: mdl-20366976

ABSTRACT

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.

11.
Int J Artif Organs ; 25(9): 875-81, 2002 Sep.
Article in English | MEDLINE | ID: mdl-12403404

ABSTRACT

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.


Subject(s)
Anticoagulants/administration & dosage , Cardiopulmonary Bypass/instrumentation , Coated Materials, Biocompatible , Heparin/administration & dosage , Phosphorylcholine , Cardiopulmonary Bypass/methods , Case-Control Studies , Clinical Protocols , Dose-Response Relationship, Drug , Feasibility Studies , Female , Humans , Male , Middle Aged , Outcome Assessment, Health Care , Time Factors , Whole Blood Coagulation Time
12.
Minerva Cardioangiol ; 47(7-8): 231-8, 1999.
Article in English, Italian | MEDLINE | ID: mdl-10582433

ABSTRACT

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.


Subject(s)
Coronary Disease/diagnostic imaging , Myocardial Infarction/diagnostic imaging , Myocardial Revascularization , Acute Disease , Coronary Angiography , Coronary Disease/surgery , Female , Humans , Male , Myocardial Infarction/surgery , Retrospective Studies
13.
Minerva Cardioangiol ; 45(9): 407-14, 1997 Sep.
Article in Italian | MEDLINE | ID: mdl-9446061

ABSTRACT

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.


Subject(s)
Electrocardiography , Myocardial Infarction/diagnosis , Myocardial Reperfusion/methods , Female , Humans , Male , Middle Aged , Myocardial Infarction/therapy , Thrombolytic Therapy , Time Factors
14.
Minerva Cardioangiol ; 44(7-8): 369-72, 1996.
Article in Italian | MEDLINE | ID: mdl-8965994

ABSTRACT

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.


Subject(s)
Echocardiography, Transesophageal , Pulmonary Embolism/diagnostic imaging , Aged , Humans , Male
15.
Studi Emigr ; 33(122): 273-303, 1996 Jun.
Article in Italian | MEDLINE | ID: mdl-12292144

ABSTRACT

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)


Subject(s)
Economics , Emigration and Immigration , Geography , Population Dynamics , Social Change , Socioeconomic Factors , Demography , Developed Countries , Europe , Italy , Population
16.
Estud Migr Latinoam ; 11(32): 169-77, 1996 Apr.
Article in Spanish | MEDLINE | ID: mdl-12348135

ABSTRACT

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


Subject(s)
Age Distribution , Emigration and Immigration , Employment , Family Characteristics , Marriage , Sexual Behavior , Age Factors , Demography , Developed Countries , Developing Countries , Economics , Europe , Fertility , Italy , Latin America , Population , Population Characteristics , Population Dynamics , Social Class , Socioeconomic Factors
17.
Minerva Cardioangiol ; 43(10): 443-7, 1995 Oct.
Article in Italian | MEDLINE | ID: mdl-8819813

ABSTRACT

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.


Subject(s)
Endocarditis, Bacterial/diagnostic imaging , Pregnancy Complications, Cardiovascular/diagnostic imaging , Pregnancy Complications, Infectious/diagnostic imaging , Puerperal Disorders/diagnostic imaging , Adult , Anti-Bacterial Agents/therapeutic use , Echocardiography/methods , Endocarditis, Bacterial/drug therapy , Endocarditis, Bacterial/epidemiology , Female , Humans , Incidence , Mitral Valve Insufficiency/diagnostic imaging , Pregnancy , Pregnancy Complications, Cardiovascular/drug therapy , Pregnancy Complications, Cardiovascular/epidemiology , Pregnancy Complications, Infectious/drug therapy , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/microbiology , Puerperal Disorders/drug therapy , Treatment Outcome
19.
Genus ; 48(1-2): 47-67, 1992.
Article in Italian | MEDLINE | ID: mdl-12317870

ABSTRACT

"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)


Subject(s)
Geography , Methods , Population Dynamics , Demography , Developed Countries , Emigration and Immigration , Europe , Italy , Population
20.
Genus ; 45(3-4): 37-54, 1989.
Article in English | MEDLINE | ID: mdl-12283195

ABSTRACT

PIP: Findings are analyzed of the Instituto di Richerche solla poplazione survey carried out in Italy in 1987 which focused on: 1) those variables which may be indirectly affecting Italian's fertility intentions, and 2) the degree of acceptability of a global social policy i.e., one that is not only restricted to economic incentives to be offered to families. Data was obtained from a national sample of 1500 people between 18-49 years. Italians have a good awareness of demographic issues; 61% knew of the decline in marriages; 72% were aware of the increasing aging population; 50% viewed the fall in birth rate negatively; and 41% thought that population and fertility trends would remain at the present low level or would decrease even further (49%). The birth rate decline was contributed to economic reasons at both reasons at both a global and an individual level. The majority of people did not show any signs of prejudice toward immigrants; however, they did favor limiting the number of foreigners in general with the exception of political refugees. The majority were also in favor of helping 3rd World countries. Although Italians value their children and the parent-child relationship very highly, a reduction in the value of children with increasing educational level of the respondents was observed. 83% thought that couples should be allowed to have as many children as they wanted; 81% agreed that measures regarding contraceptive knowledge and availability should be improved; and 49% were in favor of measures to increase births. Regarding possible new policy measures, 50% were in full agreement on the development and increased efficiency of social services to enable women to go out to work. (author's modified)^ieng


Subject(s)
Attitude , Child , Data Collection , Demography , Knowledge , Public Policy , Statistics as Topic , Behavior , Developed Countries , Economics , Europe , Italy , Population , Population Dynamics , Psychology , Research , Sampling Studies
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