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2.
  • Akkoyun, S., et al. (author)
  • AGATA - Advanced GAmma Tracking Array
  • 2012
  • In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002 .- 0167-5087 .- 1872-9576. ; 668, s. 26-58
  • Journal article (peer-reviewed)abstract
    • The Advanced GAmma Tracking Array (AGATA) is a European project to develop and operate the next generation γ-ray spectrometer. AGATA is based on the technique of γ-ray energy tracking in electrically segmented high-purity germanium crystals. This technique requires the accurate determination of the energy, time and position of every interaction as a γ ray deposits its energy within the detector volume. Reconstruction of the full interaction path results in a detector with very high efficiency and excellent spectral response. The realisation of γ-ray tracking and AGATA is a result of many technical advances. These include the development of encapsulated highly segmented germanium detectors assembled in a triple cluster detector cryostat, an electronics system with fast digital sampling and a data acquisition system to process the data at a high rate. The full characterisation of the crystals was measured and compared with detector- response simulations. This enabled pulse-shape analysis algorithms, to extract energy, time and position, to be employed. In addition, tracking algorithms for event reconstruction were developed. The first phase of AGATA is now complete and operational in its first physics campaign. In the future AGATA will be moved between laboratories in Europe and operated in a series of campaigns to take advantage of the different beams and facilities available to maximise its science output. The paper reviews all the achievements made in the AGATA project including all the necessary infrastructure to operate and support the spectrometer. © 2011 Elsevier B.V. All rights reserved.
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4.
  • Aprile, E., et al. (author)
  • The XENON1T dark matter experiment
  • 2017
  • In: European Physical Journal C. - : Springer Science and Business Media LLC. - 1434-6044 .- 1434-6052. ; 77:12
  • Journal article (peer-reviewed)abstract
    • The XENON1T experiment at the Laboratori Nazionali del Gran Sasso (LNGS) is the first WIMP dark matter detector operating with a liquid xenon target mass above the ton-scale. Out of its 3.2t liquid xenon inventory, 2.0t constitute the active target of the dual-phase time projection chamber. The scintillation and ionization signals from particle interactions are detected with low-background photomultipliers. This article describes the XENON1T instrument and its subsystems as well as strategies to achieve an unprecedented low background level. First results on the detector response and the performance of the subsystems are also presented.
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5.
  • Bree, N, et al. (author)
  • Shape Coexistence in the Neutron-Deficient Even-Even Hg182-188 Isotopes Studied via Coulomb Excitation.
  • 2014
  • In: Physical Review Letters. - 1079-7114. ; 112:16
  • Journal article (peer-reviewed)abstract
    • Coulomb-excitation experiments to study electromagnetic properties of radioactive even-even Hg isotopes were performed with 2.85 MeV/nucleon mercury beams from REX-ISOLDE. Magnitudes and relative signs of the reduced E2 matrix elements that couple the ground state and low-lying excited states in Hg182-188 were extracted. Information on the deformation of the ground and the first excited 0+ states was deduced using the quadrupole sum rules approach. Results show that the ground state is slightly deformed and of oblate nature, while a larger deformation for the excited 0+ state was noted in Hg182,184. The results are compared to beyond mean field and interacting-boson based models and interpreted within a two-state mixing model. Partial agreement with the model calculations was obtained. The presence of two different structures in the light even-mass mercury isotopes that coexist at low excitation energy is firmly established.
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7.
  • Paciaroni, M., et al. (author)
  • Timing of initiation of oral anticoagulants in patients with acute ischemic stroke and atrial fibrillation comparing posterior and anterior circulation strokes
  • 2020
  • In: European Stroke Journal. - : SAGE Publications. - 2396-9873 .- 2396-9881.
  • Journal article (peer-reviewed)abstract
    • Introduction: The aim of this study in patients with acute posterior ischaemic stroke (PS) and atrial fibrillation (AF) was to evaluate (1) the risks of recurrent ischaemic event and severe bleeding and (2) these risks in relation with oral anticoagulant therapy (OAT) and its timing. Materials and Methods: Patients with PS were prospectively included; the outcome events of these patients were compared with those of patients with anterior stroke (AS) which were taken from previous registries. The primary outcome was the composite of stroke recurrence, transient ischaemic attack, symptomatic systemic embolism, symptomatic cerebral bleeding and major extracranial bleeding occurring within 90 days from acute stroke. Results: A total of 2470 patients were available for the analysis: 473 (19.1%) with PS and 1997 (80.9%) with AS. Over 90 days, 213 (8.6%) primary outcome events were recorded: 175 (8.7%) in patients with AS and 38 (8.0%) in those with PS. In patients who initiated OAT within 2 days, the primary outcome occurred in 5 out of 95 patients (5.3%) with PS compared to 21 out of 373 patients (4.3%) with AS (OR 1.07; 95% CI 0.39-2.94). In patients who initiated OAT between days 3 and 7, the primary outcome occurred in 3 out of 103 patients (2.9%) with PS compared to 26 out of 490 patients (5.3%) with AS (OR 0.54; 95% CI 0.16-1.80). Discussion: our findings suggest that, when deciding the time to initiate oral anticoagulation, the location of stroke, either anterior or posterior, does not predict the risk of outcome events. Conclusions: Patients with PS or AS and AF appear to have similar risks of ischaemic or haemorrhagic events at 90 days with no difference concerning the timing of initiation of OAT.
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8.
  • Wrzosek-Lipska, K., et al. (author)
  • Electromagnetic properties of low-lying states in neutron-deficient Hg isotopes : Coulomb excitation of 182Hg, 184Hg, 186Hg and 188Hg
  • 2019
  • In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 55:8
  • Journal article (peer-reviewed)abstract
    • The neutron-deficient mercury isotopes serve as a classical example of shape coexistence, whereby at low energy near-degenerate nuclear states characterized by different shapes appear. The electromagnetic structure of even-mass 182-188 Hg isotopes was studied using safe-energy Coulomb excitation of neutron-deficient mercury beams delivered by the REX-ISOLDE facility at CERN. The population of 01,2+, 21,2+ and 41+ states was observed in all nuclei under study. Reduced E2 matrix elements coupling populated yrast and non-yrast states were extracted, including their relative signs. These are a sensitive probe of shape coexistence and may be used to validate nuclear models. The experimental results are discussed in terms of mixing of two different configurations and are compared with three different model calculations: the Beyond Mean Field model, the Interacting Boson Model with configuration mixing and the General Bohr Hamiltonian. Partial agreement with experiment was observed, hinting to missing ingredients in the theoretical descriptions.
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9.
  • Doncel, Maria, et al. (author)
  • Lifetime Measurements in Neutron-rich Cu Isotopes
  • 2013
  • In: Acta Physica Polonica B. - 0587-4254 .- 1509-5770. ; 44:3, s. 505-510
  • Journal article (peer-reviewed)abstract
    • The nuclear structure of neutron-rich nuclei close to the double-magic nucleus Ni-78 has been investigated by measuring the lifetime of excited states. In this contribution, it will be presented the lifetime of the J(pi) = 7/2(-) excited state at 981 keV of the Cu-71 isotope, measured using the AGATA Demonstrator coupled to the PRISMA spectrometer and the Koln plunger setup. This is the first time this combined setup has been used for a lifetime measurement.
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10.
  • Giustozzi, M., et al. (author)
  • Safety of Anticoagulation in Patients Treated with Urgent Reperfusion for Ischemic Stroke Related to Atrial Fibrillation
  • 2020
  • In: Stroke. - 0039-2499. ; 51:8, s. 2347-2354
  • Journal article (peer-reviewed)abstract
    • Background and Purpose: The optimal timing for starting oral anticoagulant after an ischemic stroke related to atrial fibrillation remains a challenge, mainly in patients treated with systemic thrombolysis or mechanical thrombectomy. We aimed at assessing the incidence of early recurrence and major bleeding in patients with acute ischemic stroke and atrial fibrillation treated with thrombolytic therapy and/or thrombectomy, who then received oral anticoagulants for secondary prevention. Methods: We combined the dataset of the RAF and the RAF-NOACs (Early Recurrence and Major Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Treated With Non-Vitamin K Oral Anticoagulants) studies, which were prospective observational studies carried out from January 2012 to March 2014 and April 2014 to June 2016, respectively. We included consecutive patients with acute ischemic stroke and atrial fibrillation treated with either vitamin K antagonists or nonvitamin K oral anticoagulants. Primary outcome was the composite of stroke, transient ischemic attack, symptomatic systemic embolism, symptomatic cerebral bleeding, and major extracerebral bleeding within 90 days from the inclusion. Treated-patients were propensity matched to untreated-patients in a 1:1 ratio after stratification by baseline clinical features. Results: A total of 2159 patients were included, 564 (26%) patients received acute reperfusion therapies. After the index event, 505 (90%) patients treated with acute reperfusion therapies and 1287 of 1595 (81%) patients untreated started oral anticoagulation. Timing of starting oral anticoagulant was similar in reperfusion-treated and untreated patients (median 7.5 versus 7.0 days, respectively). At 90 days, the primary study outcome occurred in 37 (7%) patients treated with reperfusion and in 146 (9%) untreated patients (odds ratio, 0.74 [95% CI, 0.50-1.07]). After propensity score matching, risk of primary outcome was comparable between the 2 groups (odds ratio, 1.06 [95% CI, 0.53-2.02]). Conclusions: Acute reperfusion treatment did not influence the risk of early recurrence and major bleeding in patients with atrial fibrillation-related acute ischemic stroke, who started on oral anticoagulant. © 2020 Georg Thieme Verlag. All rights reserved.
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11.
  • Louchart, C., et al. (author)
  • Collective nature of low-lying excitations in Zn-70,Zn-72,Zn-74 from lifetime measurements using the AGATA spectrometer demonstrator
  • 2013
  • In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 87:5
  • Journal article (peer-reviewed)abstract
    • Background: Neutron-rich nuclei with protons in the fp shell show an onset of collectivity around N=40. Spectroscopic information is required to understand the underlying mechanism and to determine the relevant terms of the nucleon-nucleon interaction that are responsible for the evolution of the shell structure in this mass region. Methods: We report on the lifetime measurement of the first 2(+) and 4(+) states in Zn-70,Zn-72 ,Zn-74 and the first 6(+) state in Zn-72 using the recoil distance Doppler shift method. The experiment was carried out at the INFN Laboratory of Legnaro with the AGATA demonstrator, first phase of the Advanced Gamma Tracking Array of highly segmented, high-purity germanium detectors coupled to the PRISMA magnetic spectrometer. The excited states of the nuclei of interest were populated in the deep inelastic scattering of a Ge-76 beam impinging on a U-238 target. Results: The maximum of collectivity along the chain of Zn isotopes is observed for Zn-72 at N=42. An unexpectedly long lifetime of 20(-5.2)(+1.8) ps was measured for the 4(+) state in Zn-74. Conclusions: Our results lead to small values of the B(E2;4(1)(+) -> 21(+))/B(E2;2(1)(+->)0(1)(+)) ratio for Zn-72,Zn-74, suggesting a significant noncollective contribution to these excitations. These experimental results are not reproduced by state-of-the-art microscopic models and call for lifetime measurements beyond the first 2(+) state in heavy zinc and nickel isotopes.
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12.
  • Sahin, E., et al. (author)
  • Shell evolution beyond N=40 : Cu-69,Cu-71,Cu-73
  • 2015
  • In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 91:3
  • Journal article (peer-reviewed)abstract
    • The level structure of the neutron-rich Cu-69, Cu-71, and Cu-73 isotopes has been investigated by means of multinucleon transfer reactions. The experiment was performed at Laboratori Nazionali di Legnaro using the AGATA Demonstrator array coupled to the PRISMA magnetic spectrometer. Lifetimes of excited states in Cu nuclei were measured with the recoil-distance Doppler-shift method. The resulting electromagnetic matrix elements for transitions from excited states in Cu-69,Cu-71,Cu-73 nuclei are used to assess the collective or single-particle character of these states. The results are compared with predictions of large-scale shell-model calculations, giving further insight into the evolution of the proton pf shell as neutrons fill the 1g(9/2) orbital.
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  • Altavilla, R., et al. (author)
  • Anticoagulation After Stroke in Patients With Atrial Fibrillation: To Bridge or Not With Low-Molecular-Weight Heparin?
  • 2019
  • In: Stroke. - : Ovid Technologies (Wolters Kluwer Health). - 0039-2499 .- 1524-4628. ; 50:8, s. 2093-2100
  • Journal article (peer-reviewed)abstract
    • Background and Purpose- Bridging therapy with low-molecular-weight heparin reportedly leads to a worse outcome for acute cardioembolic stroke patients because of a higher incidence of intracerebral bleeding. However, this practice is common in clinical settings. This observational study aimed to compare (1) the clinical profiles of patients receiving and not receiving bridging therapy, (2) overall group outcomes, and (3) outcomes according to the type of anticoagulant prescribed. Methods- We analyzed data of patients from the prospective RAF and RAF-NOACs studies. The primary outcome was defined as the composite of ischemic stroke, transient ischemic attack, systemic embolism, symptomatic cerebral bleeding, and major extracerebral bleeding observed at 90 days after the acute stroke. Results- Of 1810 patients who initiated oral anticoagulant therapy, 371 (20%) underwent bridging therapy with full-dose low-molecular-weight heparin. Older age and the presence of leukoaraiosis were inversely correlated with the use of bridging therapy. Forty-two bridged patients (11.3%) reached the combined outcome versus 72 (5.0%) of the nonbridged patients (P=0.0001). At multivariable analysis, bridging therapy was associated with the composite end point (odds ratio, 2.3; 95% CI, 1.4-3.7; P<0.0001), as well as ischemic (odds ratio, 2.2; 95% CI, 1.3-3.9; P=0.005) and hemorrhagic (odds ratio, 2.4; 95% CI, 1.2-4.9; P=0.01) end points separately. Conclusions- Our findings suggest that patients receiving low-molecular-weight heparin have a higher risk of early ischemic recurrence and hemorrhagic transformation compared with nonbridged patients.
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14.
  • Apponi, A., et al. (author)
  • Heisenberg's uncertainty principle in the PTOLEMY project : A theory update
  • 2022
  • In: Physical Review D. - : American Physical Society. - 2470-0010 .- 2470-0029. ; 106:5
  • Journal article (peer-reviewed)abstract
    • We discuss the consequences of the quantum uncertainty on the spectrum of the electron emitted by the beta-processes of a tritium atom bound to a graphene sheet. We analyze quantitatively the issue recently raised by Cheipesh, Cheianov, and Boyarsky [Phys. Rev. D 104, 116004 (2021)], and discuss the relevant timescales and the degrees of freedom that can contribute to the intrinsic spread in the electron energy. We perform careful calculations of the potential between tritium and graphene with different coverages and geometries. With this at hand, we propose possible avenues to mitigate the effect of the quantum uncertainty.
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15.
  • Apponi, A., et al. (author)
  • Implementation and optimization of the PTOLEMY transverse drift electromagnetic filter
  • 2022
  • In: Journal of Instrumentation. - : IOP Publishing Ltd. - 1748-0221. ; 17:5
  • Journal article (peer-reviewed)abstract
    • The PTOLEMY transverse drift filter is a new concept to enable precision analysis of the energy spectrum of electrons near the tritium beta-decay endpoint. This paper details the implementation and optimization methods for successful operation of the filter for electrons with a known pitch angle. We present the first demonstrator that produces the required magnetic field properties with an iron return-flux magnet. Two methods for the setting of filter electrode voltages are detailed. The challenges of low-energy electron transport in cases of low field are discussed, such as the growth of the cyclotron radius with decreasing magnetic field, which puts a ceiling on filter performance relative to fixed filter dimensions. Additionally, low pitch angle trajectories are dominated by motion parallel to the magnetic field lines and introduce non-adiabatic conditions and curvature drift. To minimize these effects and maximize electron acceptance into the filter, we present a three-potential-well design to simultaneously drain the parallel and transverse kinetic energies throughout the length of the filter. These optimizations are shown, in simulation, to achieve low-energy electron transport from a 1 T iron core (or 3 T superconducting) starting field with initial kinetic energy of 18.6 keV drained to < 10 eV (< 1 eV) in about 80 cm. This result for low field operation paves the way for the first demonstrator of the PTOLEMY spectrometer for measurement of electrons near the tritium endpoint to be constructed at the Gran Sasso National Laboratory (LNGS) in Italy.
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16.
  • Grodner, E., et al. (author)
  • Hindered Gamow-Teller Decay to the Odd-Odd N=Z 62Ga: Absence of Proton-Neutron T=0 Condensate in A=62
  • 2014
  • In: Physical Review Letters. - 1079-7114. ; 113:9
  • Journal article (peer-reviewed)abstract
    • Search for a new kind of superfluidity built on collective proton-neutron pairs with aligned spin is performed studying the Gamow-Teller decay of the T=1, Jπ=0+ ground state of Ge62 into excited states of the odd-odd N=Z nucleus Ga62. The experiment is performed at GSI Helmholtzzentrum für Schwerionenforschung with the Ge62 ions selected by the fragment separator and implanted in a stack of Si-strip detectors, surrounded by the RISING Ge array. A half-life of T1/2=82.9(14) ms is measured for the Ge62 ground state. Six excited states of Ga62, populated below 2.5 MeV through Gamow-Teller transitions, are identified. Individual Gamow-Teller transition strengths agree well with theoretical predictions of the interacting shell model and the quasiparticle random phase approximation. The absence of any sizable low-lying Gamow-Teller strength in the reported beta-decay experiment supports the hypothesis of a negligible role of coherent T=0 proton-neutron correlations in Ga62.
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17.
  • Jentschel, M., et al. (author)
  • EXILL - a high-efficiency, high-resolution setup for gamma-spectroscopy at an intense cold neutron beam facility
  • 2017
  • In: Journal of Instrumentation. - : IOP PUBLISHING LTD. - 1748-0221. ; 12
  • Journal article (peer-reviewed)abstract
    • In the EXILL campaign a highly efficient array of high purity germanium (HPGe) detectors was operated at the cold neutron beam facility PF1B of the Institut Laue-Langevin (ILL) to carry out nuclear structure studies, via measurements of gamma-rays following neutron-induced capture and fission reactions. The setup consisted of a collimation system producing a pencil beam with a thermal capture equivalent flux of about 10(8) ns(-1)cm(2) at the target position and negligible neutron halo. The targetwas surrounded by an array of eight to ten anti-Compton shielded EXOGAMClover detectors, four to six anti-Compton shielded large coaxial GASP detectors and two standard Clover detectors. For a part of the campaign the array was combined with 16 LaBr3:(Ce) detectors from the FATIMA collaboration. The detectorswere arranged in an array of rhombicuboctahedron geometry, providing the possibility to carry out very precise angular correlation and directional-polarization correlation measurements. The triggerless acquisition system allowed a signal collection rate of up to 6 x 10(5) Hz. The data allowed to set multi-fold coincidences to obtain decay schemes and in combination with the FATIMA array of LaBr3:(Ce) detectors to analyze half-lives of excited levels in the pico-to microsecond range. Precise energy and efficiency calibrations of EXILL were performed using standard calibration sources of Ba-133, Co-60 and Eu-152 as well as data from the reactions Al-27(n, gamma)Al-28 and Cl-35(n,gamma)Cl-36 in the energy range from 30 keV up to 10MeV.
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18.
  • Paciaroni, M., et al. (author)
  • Early Recurrence and Major Bleeding in Patients With Acute Ischemic Stroke and Atrial Fibrillation Treated With Non-Vitamin-K Oral Anticoagulants (RAF-NOACs) Study
  • 2017
  • In: Journal of the American Heart Association. - : Ovid Technologies (Wolters Kluwer Health). - 2047-9980. ; 6:12
  • Journal article (peer-reviewed)abstract
    • Background-The optimal timing to administer non-vitamin K oral anticoagulants (NOACs) in patients with acute ischemic stroke and atrial fibrillation is unclear. This prospective observational multicenter study evaluated the rates of early recurrence and major bleeding (within 90 days) and theirtiming in patients with acute ischemic stroke and atrial fibrillation who received NOACs for secondary prevention. Methods and Results-Recurrence was defined as the composite of ischemic stroke, transient ischemic attack, and symptomatic systemic embolism, and major bleeding was defined as symptomatic cerebral and major extracranial bleeding. For the analysis, 1127 patients were eligible: 381 (33.8%) were treated with dabigatran, 366 (32.5%) with rivaroxaban, and 380 (33.7%) with apixaban. Patients who received dabigatran were younger and had lower admission National Institutes of Health Stroke Scale score and less commonly had a CHA(2)DS(2)-VASc score >4 and less reduced renal function. Thirty-two patients (2.8%) had early recurrence, and 27 (2.4%) had major bleeding. The rates of early recurrence and major bleeding were, respectively, 1.8% and 0.5% in patients receiving dabigatran, 1.6% and 2.5% in those receiving rivaroxaban, and 4.0% and 2.9% in those receiving apixaban. Patients who initiated NOACs within 2 days after acute stroke had a composite rate of recurrence and major bleeding of 12.4%; composite rates were 2.1% for those who initiated NOACs between 3 and 14 days and 9.1% for those who initiated > 14 days after acute stroke. Conclusions-In patients with acute ischemic stroke and atrial fibrillation, treatment with NOACs was associated with a combined 5% rate of ischemic embolic recurrence and severe bleeding within 90 days.
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  • Paciaroni, M., et al. (author)
  • Hemorrhagic transformation in patients with acute ischemic stroke and atrial fibrillation: Time to initiation of oral anticoagulant therapy and outcomes
  • 2018
  • In: Journal of the American Heart Association. - 2047-9980. ; 7:22
  • Journal article (peer-reviewed)abstract
    • Background—In patients with acute ischemic stroke and atrial fibrillation, early anticoagulation prevents ischemic recurrence but with the risk of hemorrhagic transformation (HT). The aims of this study were to evaluate in consecutive patients with acute stroke and atrial fibrillation (1) the incidence of early HT, (2) the time to initiation of anticoagulation in patients with HT, (3) the association of HT with ischemic recurrences, and (4) the association of HT with clinical outcome at 90 days. Methods and Results—HT was diagnosed by a second brain computed tomographic scan performed 24 to 72 hours after stroke onset. The incidence of ischemic recurrences as well as mortality or disability (modified Rankin Scale scores >2) were evaluated at 90 days. Ischemic recurrences were the composite of ischemic stroke, transient ischemic attack, or systemic embolism. Among the 2183 patients included in the study, 241 (11.0%) had HT. Patients with and without HT initiated anticoagulant therapy after a mean 23.3 and 11.6 days, respectively, from index stroke. At 90 days, 4.6% (95% confidence interval, 2.3-8.0) of the patients with HT had ischemic recurrences compared with 4.9% (95% confidence interval, 4.0-6.0) of those without HT; 53.1% of patients with HT were deceased or disabled compared with 35.8% of those without HT. On multivariable analysis, HT was associated with mortality or disability (odds ratio, 1.71; 95% confidence interval, 1.24-2.35). Conclusions—In patients with HT, anticoagulation was initiated about 12 days later than patients without HT. This delay was not associated with increased detection of ischemic recurrence. HT was associated with increased mortality or disability. © 2018 The Authors.
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20.
  • Paciaroni, M., et al. (author)
  • Prediction of Early Recurrent Thromboembolic Event and Major Bleeding in Patients With Acute Stroke and Atrial Fibrillation by a Risk Stratification Schema The ALESSA Score Study
  • 2017
  • In: Stroke. - : Ovid Technologies (Wolters Kluwer Health). - 0039-2499 .- 1524-4628. ; 48:3, s. 726-732
  • Journal article (peer-reviewed)abstract
    • Background and Purposes-This study was designed to derive and validate a score to predict early ischemic events and major bleedings after an acute ischemic stroke in patients with atrial fibrillation. Methods-The derivation cohort consisted of 854 patients with acute ischemic stroke and atrial fibrillation included in prospective series between January 2012 and March 2014. Older age (hazard ratio 1.06 for each additional year; 95% confidence interval, 1.00-1.11) and severe atrial enlargement (hazard ratio, 2.05; 95% confidence interval, 1.08-2.87) were predictors for ischemic outcome events (stroke, transient ischemic attack, and systemic embolism) at 90 days from acute stroke. Small lesions (1.5 cm) were inversely correlated with both major bleeding (hazard ratio, 0.39; P=0.03) and ischemic outcome events (hazard ratio, 0.55; 95% confidence interval, 0.30-1.00). We assigned to age 80 years 2 points and between 70 and 79 years 1 point; ischemic index lesion >1.5 cm, 1 point; severe atrial enlargement, 1 point (ALESSA score). A logistic regression with the receiver-operating characteristic graph procedure (C statistic) showed an area under the curve of 0.697 (0.632-0.763; P=0.0001) for ischemic outcome events and 0.585 (0.493-0.678; P=0.10) for major bleedings. Results-The validation cohort consisted of 994 patients included in prospective series between April 2014 and June 2016. Logistic regression with the receiver-operating characteristic graph procedure showed an area under the curve of 0.646 (0.529-0.763; P=0.009) for ischemic outcome events and 0.407 (0.275-0.540; P=0.14) for hemorrhagic outcome events. Conclusions-In acute stroke patients with atrial fibrillation, high ALESSA scores were associated with a high risk of ischemic events but not of major bleedings.
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24.
  • Aktas, Özge, 1987-, et al. (author)
  • First observation of γ-ray transitions in 111Mo
  • In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X.
  • Journal article (peer-reviewed)abstract
    • Excited states in the extremely neutron-rich nuclei 109Mo and 111Mo have been studied following nucleon knock-out reactions. Seven $\gamma$-ray transitions, some of them in prompt mutual coincidence, have been identified for the first time in 11Mo using the DALI2 and MINOS detector systems at the BigRIPS and ZeroDegree electromagnetic fragments separator at the RIBF, RIKEN, Japan. Total Routhian surface (TRS) and Particle- Plus Rotor calculations have been performed to investigate the predicted shape coexistence and its effect on the structure of nuclei in this region of the nuclear chart. Following the results of the calculations, theoretical level schemes are proposed for positive and negative parity states and compared with the experimental findings.
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25.
  • Aktas, Özge, et al. (author)
  • Single-particle structures in 85,87Ge
  • In: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X.
  • Journal article (peer-reviewed)abstract
    • Gamma-ray transitions have been identified for the first time in the extremely neutron-rich (N =Z + 25) nucleus 87 Ge following nucleon knockout reactions studied at the RIBF, RIKEN, Japan.New γ-ray transitions from excited states in 85 Ge were also observed and placed in a tentative levelscheme. The exclusive parallel momentum distribution was measured for the 1/2 + state for theneutron knockout reaction leading to 85 Ge which is compared with calculated distorted wave impulseapproximation (DWIA) distributions. The 85,87 Ge results are compared with large-scale shell-modelcalculations and potential energy surface calculations based on the total Routhian surface formalism.
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28.
  • DiJulio, Douglas, et al. (author)
  • Electromagnetic properties of vibrational bands in Er-170
  • 2011
  • In: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 47:2, s. 25-
  • Journal article (peer-reviewed)abstract
    • Excited states of the nucleus Er-170 have been studied by Coulomb excitation using the GASP gamma-ray detector system at the Laboratori Nazionali di Legnaro. The ground-state band along with a low-lying K-pi = 0(+) band and gamma-vibrational band were populated during the experiment. Based on the measured gamma-ray yields, a set of interband and intraband matrix elements has been extracted using the Coulomb excitation code GOSIA. The resulting E2 matrix elements are compared to collective model predictions.
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30.
  • Kröll, T., et al. (author)
  • Transfer Reactions on Neutron-rich Nuclei at REX-ISOLDE
  • 2009
  • In: AIP Conference Proceedings. - 1551-7616 .- 0094-243X. ; 1165, s. 363-368 461
  • Conference paper (peer-reviewed)abstract
    • We report on one- and two-neutron transfer reactions to study the single-particle properties of nuclei at the border of the "island of inversion". The (d,p)- and (t,p)-reactions in inverse kinematics on the neutron-rich isotope Mg-30, delivered as radioactive beam by the REX-ISOLDE facility, have been investigated. The outgoing protons have been detected and identified by a newly built array of Si detectors. The gamma-decay of excited states has been detected in coincidence by the MINIBALL array. First results for Mg-31 and from the search for the second, spherical, 0(+) state in Mg-32 are presented.
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31.
  • Aires, F., et al. (author)
  • Microwave hyperspectral measurements for temperature and humidity atmospheric profiling from satellite: The clear-sky case
  • 2015
  • In: Journal of Geophysical Research. - 0148-0227 .- 2156-2202 .- 2169-897X .- 2169-8996. ; 120:21, s. 11334-11351
  • Journal article (peer-reviewed)abstract
    • This study investigates the benefits of a satellite HYperspectral Microwave Sensor (HYMS) for the retrieval of atmospheric temperature and humidity profiles, in the context of numerical weather prediction (NWP). In the infrared, hyperspectral instruments have already improved the accuracy of NWP forecasts. Microwave instruments so far only provide observations for a limited number of carefully selected channels. An information content analysis is conducted here to assess the impact of hyperspectral microwave measurements on the retrieval of temperature and water vapor profiles under clear-sky conditions. It uses radiative transfer simulations over a large variety of atmospheric situations. It accounts for realistic observation (instrument and radiative transfer) noise and for a priori information assumptions compatible with NWP practices. The estimated retrieval performance of the HYMS instrument is compared to those of the microwave instruments to be deployed on board the future generation of European operational meteorological satellites (MetOp-SG). The results confirm the positive impact of a HYMS instrument on the atmospheric profiling capabilities compared to MetOp-SG. Temperature retrieval uncertainty, compared to a priori information, is reduced by 2 to 10%, depending on the atmospheric height, and improvement rates are much higher than what will be obtained with MetOp-SG. For humidity sounding these improvements can reach 30%, a significant benefit as compared to MetOp-SG results especially below 250 hPa. The results are not very sensitive to the instrument noise, under our assumptions. The main impact provided by the hyperspectral information originates from the higher resolution in the O2 band around 60 GHz. The results are presented over ocean at nadir, but similar conclusions are obtained for other incidence angles and over land. Key Points A hyperspectral MW instrument could improve temperature & humidity retrieval compared to MetOp-SG The main impact from HYMS comes from higher resolution in the O2 band around 60 GHz Hyperspectral information is not really sensitive to instrument noise.
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32.
  • Awah, Nancy, 1976-, et al. (author)
  • Antibodies to the Plasmodium falciparum rhoptry protein RAP-2/RSP-2 in relation to anaemia in Cameroonian children
  • 2011
  • In: Parasite immunology (Print). - : Wiley. - 0141-9838 .- 1365-3024. ; 33:2, s. 104-115
  • Journal article (peer-reviewed)abstract
    • Previous studies have implicated reactive antibodies to the low molecular weight rhoptry-associated proteins (RAP-1, RAP-2/RSP-2 and RAP-3) in erythroid cell destruction during Plasmodium falciparum infection. In this pilot study, the frequency, specificity and functional capacity of naturally acquired anti-RAP-2/RSP-2 antibodies were investigated in the sera of anaemic and nonanaemic malaria-infected Cameroonian children. All sera recognized RAP-2/RSP-2 by FACS, irrespective of the clinical status of the subjects. However, the anaemic children showed higher levels of IgG antibodies than the nonanaemic group, while both groups showed similar levels of IgM antibodies. Only few individuals had detectable levels of RAP-2/RSP-2-specific IgG1 and IgG3 subclass antibodies, while no IgG2 and IgG4 subclass antibodies were detected in these subjects. By ELISA, the anaemic group tended to show higher levels of antibodies to RAP-2/RSP-2 regarding all antibody classes tested, except for IgG4 and IgE. Unexpectedly, sera from the nonanaemic group activated complement to a greater extent than those from the anaemic group. These results need to be confirmed in extended studies but indicate that the effector functions of the RAP-2/RSP-2-reactive antibodies may be more important than their amounts. Such antibodies could play a role in both immunity and pathogenesis during P. falciparum infection.
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33.
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34.
  • Gaffney, L. P., et al. (author)
  • Collectivity in the light radon nuclei measured directly via Coulomb excitation
  • 2015
  • In: Physical Review C (Nuclear Physics). - 0556-2813. ; 91:6
  • Journal article (peer-reviewed)abstract
    • Background: Shape coexistence in heavy nuclei poses a strong challenge to state-of-the-art nuclear models, where several competing shape minima are found close to the ground state. A classic region for investigating this phenomenon is in the region around Z = 82 and the neutron midshell at N = 104. Purpose: Evidence for shape coexistence has been inferred from a-decay measurements, laser spectroscopy, and in-beam measurements. While the latter allow the pattern of excited states and rotational band structures to be mapped out, a detailed understanding of shape coexistence can only come from measurements of electromagnetic matrix elements. Method: Secondary, radioactive ion beams of Rn-202 and Rn-204 were studied by means of low-energy Coulomb excitation at the REX-ISOLDE in CERN. Results: The electric-quadrupole (E2) matrix element connecting the ground state and first excited 2(1)(+) state was extracted for both Rn-202 and Rn-204, corresponding to B(E2; 2(1)(+) -> 0(1)(+)) = 29(-8)(+8) and 43(-12)(+17) W.u., respectively. Additionally, E2 matrix elements connecting the 2(1)(+) state with the 4(1)(+) and 2(2)(+) states were determined in Rn-202. No excited 0(+) states were observed in the current data set, possibly owing to a limited population of second-order processes at the currently available beam energies. Conclusions: The results are discussed in terms of collectivity and the deformation of both nuclei studied is deduced to be weak, as expected from the low-lying level-energy schemes. Comparisons are also made to state-of-the-art beyond-mean-field model calculations and the magnitude of the transitional quadrupole moments are well reproduced.
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35.
  • Gheorghiade, M., et al. (author)
  • Rationale and design of the multicenter, randomized, double-blind, placebo-controlled study to evaluate the Efficacy of Vasopressin antagonism in Heart Failure: Outcome Study with Tolvaptan (EVEREST)
  • 2005
  • In: Journal of cardiac failure. - 1071-9164. ; 11:4, s. 260-9
  • Journal article (peer-reviewed)abstract
    • BACKGROUND: Hospitalizations for worsening heart failure due to fluid overload (congestion) are common. Agents that treat congestion without causing electrolyte abnormalities or worsening renal function are needed. Tolvaptan is an oral vasopressin (V 2 ) antagonist that decreases body weight and increases urine volume without inducing renal dysfunction or hypokalemia. The Efficacy of Vasopressin antagonism in Heart Failure Outcome Study with Tolvaptan (EVEREST) trial is evaluating mortality, morbidity, and patient-assessed global clinical status in patients treated with tolvaptan compared with standard care. METHODS AND RESULTS: Patients are eligible for inclusion if they have a reduced left ventricular ejection fraction and are hospitalized for worsening heart failure with evidence of systemic congestion. Patients are randomized 1:1 to tolvaptan 30 mg/day or matching placebo for a minimum of 60 days. Time to all-cause mortality and time to cardiovascular mortality or heart failure hospitalization are the coprimary end points. Patient-assessed global clinical status and quality of life are also evaluated. EVEREST will be continued until 1065 deaths occur. As of April 18, 2005, 2260 patients have been enrolled. CONCLUSION: Tolvaptan has been shown to reduce body weight in patients with worsening heart failure without inducing renal dysfunction or causing hypokalemia. The results of EVEREST will determine whether these effects translate into improved clinical outcomes.
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36.
  • Gheorghiade, M., et al. (author)
  • Short-term clinical effects of tolvaptan, an oral vasopressin antagonist, in patients hospitalized for heart failure: the EVEREST Clinical Status Trials
  • 2007
  • In: JAMA. - 1538-3598. ; 297:12, s. 1332-43
  • Journal article (peer-reviewed)abstract
    • CONTEXT: Heart failure causes more than 1 million US hospitalizations yearly, mostly related to congestion. Tolvaptan, an oral, nonpeptide, selective vasopressin V2-receptor antagonist, shows promise in this condition. OBJECTIVE: To evaluate short-term effects of tolvaptan when added to standard therapy in patients hospitalized with heart failure. DESIGN, SETTING, AND PATIENTS: Two identical prospective, randomized, double-blind, placebo-controlled trials at 359 sites in North America, South America, and Europe were conducted during the inpatient period of the Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST) between October 7, 2003, and February 3, 2006. A total of 2048 (trial A) and 2085 (trial B) patients hospitalized with heart failure and congestion were studied. INTERVENTION: Patients were randomized to receive either tolvaptan (30 mg/d) or matching placebo, within 48 hours of admission. MAIN OUTCOME MEASURES: Primary end point was a composite of changes in global clinical status based on a visual analog scale and body weight at day 7 or discharge if earlier. Secondary end points included dyspnea (day 1), global clinical status (day 7 or discharge), body weight (days 1 and 7 or discharge), and peripheral edema (day 7 or discharge). RESULTS: Rank sum analysis of the composite primary end point showed greater improvement with tolvaptan vs placebo (trial A, mean [SD], 1.06 [0.43] vs 0.99 [0.44]; and trial B, 1.07 [0.42] vs 0.97 [0.43]; both trials P<.001). Mean (SD) body weight reduction was greater with tolvaptan on day 1 (trial A, 1.71 [1.80] vs 0.99 [1.83] kg; P<.001; and trial B, 1.82 [2.01] vs 0.95 [1.85] kg; P<.001) and day 7 or discharge (trial A, 3.35 [3.27] vs 2.73 [3.34] kg; P<.001; and trial B, 3.77 [3.59] vs 2.79 [3.46] kg; P<.001), whereas improvements in global clinical status were not different between groups. More patients receiving tolvaptan (684 [76.7%] and 678 [72.1%] for trial A and trial B, respectively) vs patients receiving placebo (646 [70.6%] and 597 [65.3%], respectively) reported improvement in dyspnea at day 1 (both trials P<.001). Edema at day 7 or discharge improved significantly with tolvaptan in trial B (P = .02) but did not reach significance in trial A (P = .07). Serious adverse event frequencies were similar between groups, without excess renal failure or hypotension. CONCLUSION: In patients hospitalized with heart failure, oral tolvaptan in addition to standard therapy including diuretics improved many, though not all, heart failure signs and symptoms, without serious adverse events. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00071331
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37.
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38.
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39.
  • Konstam, M. A., et al. (author)
  • Effects of oral tolvaptan in patients hospitalized for worsening heart failure: the EVEREST Outcome Trial
  • 2007
  • In: JAMA. - 1538-3598. ; 297:12, s. 1319-31
  • Journal article (peer-reviewed)abstract
    • CONTEXT: Vasopressin mediates fluid retention in heart failure. Tolvaptan, a vasopressin V2 receptor blocker, shows promise for management of heart failure. OBJECTIVE: To investigate the effects of tolvaptan initiated in patients hospitalized with heart failure. DESIGN, SETTING, AND PARTICIPANTS: The Efficacy of Vasopressin Antagonism in Heart Failure Outcome Study With Tolvaptan (EVEREST), an event-driven, randomized, double-blind, placebo-controlled study. The outcome trial comprised 4133 patients within 2 short-term clinical status studies, who were hospitalized with heart failure, randomized at 359 North American, South American, and European sites between October 7, 2003, and February 3, 2006, and followed up during long-term treatment. INTERVENTION: Within 48 hours of admission, patients were randomly assigned to receive oral tolvaptan, 30 mg once per day (n = 2072), or placebo (n = 2061) for a minimum of 60 days, in addition to standard therapy. MAIN OUTCOME MEASURES: Dual primary end points were all-cause mortality (superiority and noninferiority) and cardiovascular death or hospitalization for heart failure (superiority only). Secondary end points included changes in dyspnea, body weight, and edema. RESULTS: During a median follow-up of 9.9 months, 537 patients (25.9%) in the tolvaptan group and 543 (26.3%) in the placebo group died (hazard ratio, 0.98; 95% confidence interval [CI], 0.87-1.11; P = .68). The upper confidence limit for the mortality difference was within the prespecified noninferiority margin of 1.25 (P<.001). The composite of cardiovascular death or hospitalization for heart failure occurred in 871 tolvaptan group patients (42.0%) and 829 placebo group patients (40.2%; hazard ratio, 1.04; 95% CI, 0.95-1.14; P = .55). Secondary end points of cardiovascular mortality, cardiovascular death or hospitalization, and worsening heart failure were also not different. Tolvaptan significantly improved secondary end points of day 1 patient-assessed dyspnea, day 1 body weight, and day 7 edema. In patients with hyponatremia, serum sodium levels significantly increased. The Kansas City Cardiomyopathy Questionnaire overall summary score was not improved at outpatient week 1, but body weight and serum sodium effects persisted long after discharge. Tolvaptan caused increased thirst and dry mouth, but frequencies of major adverse events were similar in the 2 groups. CONCLUSION: Tolvaptan initiated for acute treatment of patients hospitalized with heart failure had no effect on long-term mortality or heart failure-related morbidity. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00071331
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40.
  • Lucani, Daniel E., et al. (author)
  • Secure generalized deduplication via multi-key revealing encryption
  • 2020
  • In: Security and Cryptography for Networks - 12th International Conference, SCN 2020, Proceedings. - Cham : Springer International Publishing. - 1611-3349 .- 0302-9743. - 9783030579890 ; 12238 LNCS, s. 298-318
  • Conference paper (peer-reviewed)abstract
    • Cloud Storage Providers (CSPs) offer solutions to relieve users from locally storing vast amounts of data, including personal and sensitive ones. While users may desire to retain some privacy on the data they outsource, CSPs are interested in reducing the total storage space by employing compression techniques such as deduplication. We propose a new cryptographic primitive that simultaneously realizes both requirements: Multi-Key Revealing Encryption (MKRE). The goal of MKRE is to disclose the result of a pre-defined function over multiple ciphertexts, even if the ciphertexts were generated using different keys, while revealing nothing else about the data. We present a formal model and a security definition for MKRE and provide a construction of MKRE for generalized deduplication that only uses symmetric key primitives in a black-box way. Our construction allows (a) cloud providers to reduce the storage space by using generalized deduplication to compress encrypted data across users, and (b) each user to maintain a certain privacy level for the outsourced information. Our scheme can be proven secure in the random oracle model (and we argue that this is a necessary evil). We develop a proof-of-concept implementation of our solution. For a test data set, our MKRE construction achieves secure generalized deduplication with a compression ratio of 87% for 1 KB file chunks and 82.2% for 8 KB chunks. Finally, our experiments show that, compared to generalized deduplication setup with un-encrypted files, adding privacy via MKRE introduces a compression overhead of less than $$3\%$$ and reduces the storage throughput by at most $$6.9\%$$.
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41.
  • Mahfouf, J.-F., et al. (author)
  • Information content on temperature and water vapour from a hyper-spectral microwave sensor
  • 2015
  • In: Quarterly Journal of the Royal Meteorological Society. - : Wiley. - 0035-9009 .- 1477-870X. ; 141:693, s. 3268-3284
  • Journal article (peer-reviewed)abstract
    • This study examines the information content on atmospheric temperature and humidity profiles that could be provided by a future spaceborne microwave sensor with a few hundred radiances in the millimetre and submillimetre spectral domains (ranging from 7–800 GHz). A channel selection method based on optimal estimation theory is undertaken, using a database of profiles with associated errors from the European Centre for Medium-Range Weather Forecasts (ECMWF) numerical weather prediction model and the radiative transfer model Atmospheric Radiative Transfer Simulator (ARTS) under clear-sky conditions. The main results indicate that, by increasing the number of channels within the oxygen absorption band around 60 GHz and within the water-vapour absorption band at 183 GHz, the accuracy of temperature and humidity retrievals in the troposphere and stratosphere (for temperature) would be noticeably improved compared with present and planned microwave radiometers. The channels located in the absorption lines at 118 GHz and above 200 GHz do not bring significant additional information regarding atmospheric profiles under clear-sky conditions, partly due to greater radiometric noise. With a set of 137 selected channels that contribute to 90% of the total information content (measured by the degree of freedom for signal), it is possible to achieve almost the same performance in terms of variance error reduction as with 276 candidate channels. Sensitivity studies of various prescribed quantities defining the channel selection have been undertaken, in order to check the robustness of the conclusions. They show that none of the choices modifies the above findings.
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42.
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43.
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44.
  • Söderström, Pär-Anders, et al. (author)
  • Interaction position resolution simulations and in-beam measurements of the AGATA HPGe detectors
  • 2011
  • In: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576. ; 638:1, s. 96-109
  • Journal article (peer-reviewed)abstract
    • The interaction position resolution of the segmented HPGe detectors of an AGATA triple cluster detector has been studied through Monte Carlo simulations and in an in-beam experiment. A new method based on measuring the energy resolution of Doppler-corrected γ-ray spectra at two different target to detector distances is described. This gives the two-dimensional position resolution in the plane perpendicular to the direction of the emitted γ-ray. The γ-ray tracking was used to determine the full energy of the γ-rays and the first interaction point, which is needed for the Doppler correction. Five different heavy-ion induced fusion-evaporation reactions and a reference reaction were selected for the simulations. The results of the simulations show that the method works very well and gives a systematic deviation of in the FWHM of the interaction position resolution for the γ-ray energy range from 60 keV to 5 MeV. The method was tested with real data from an in-beam measurement using a 30Si beam at 64 MeV on a thin 12C target. Pulse-shape analysis of the digitized detector waveforms and γ-ray tracking was performed to determine the position of the first interaction point, which was used for the Doppler corrections. Results of the dependency of the interaction position resolution on the γ-ray energy and on the energy, axial location and type of the first interaction point, are presented. The FWHM of the interaction position resolution varies roughly linearly as a function of γ-ray energy from 8.5 mm at 250 keV to 4 mm at 1.5 MeV, and has an approximately constant value of about 4 mm in the γ-ray energy range from 1.5 to 4 MeV.
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