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1.
Phys Rev Lett ; 131(22): 222501, 2023 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-38101385

RESUMEN

We report on the results obtained with the global CUPID-0 background model, which combines the data collected in the two measurement campaigns for a total exposure of 8.82 kg×yr of ^{82}Se. We identify with improved precision the background sources within the 3 MeV energy region, where neutrinoless double ß decay of ^{82}Se and ^{100}Mo is expected, making more solid the foundations for the background budget of the next-generation CUPID experiment. Relying on the excellent data reconstruction, we measure the two-neutrino double ß-decay half-life of ^{82}Se with unprecedented accuracy: T_{1/2}^{2ν}=[8.69±0.05(stat)_{-0.06}^{+0.09}(syst)]×10^{19} yr.

2.
Phys Rev Lett ; 129(11): 111801, 2022 Sep 09.
Artículo en Inglés | MEDLINE | ID: mdl-36154394

RESUMEN

CUPID-0, an array of Zn^{82}Se cryogenic calorimeters, was the first medium-scale demonstrator of the scintillating bolometers' technology. The first project phase (March 2017-December 2018) allowed the most stringent limit on the neutrinoless double beta decay half-life of the isotope of interest, ^{82}Se, to be set. After a six month long detector upgrade, CUPID-0 began its second and last phase (June 2019-February 2020). In this Letter, we describe the search for neutrinoless double beta decay of ^{82}Se with a total exposure (phase I+II) of 8.82 kg yr^{-1} of isotope. We set a limit on the half-life of ^{82}Se to the ground state of ^{82}Kr of T_{1/2}^{0ν}(^{82}Se)>4.6×10^{24} yr (90% credible interval), corresponding to an effective Majorana neutrino mass m_{ßß}<(263-545) meV. We also set the most stringent lower limits on the neutrinoless decays of ^{82}Se to the 0_{1}^{+}, 2_{1}^{+}, and 2_{2}^{+} excited states of ^{82}Kr, finding 1.8×10^{23} yr, 3.0×10^{23} yr, and 3.2×10^{23} yr (90% credible interval) respectively.

3.
Phys Rev Lett ; 123(3): 032501, 2019 Jul 19.
Artículo en Inglés | MEDLINE | ID: mdl-31386478

RESUMEN

CUPID-0 is the first pilot experiment of CUPID, a next-generation project for the measurement of neutrinoless double beta decay (0νDBD) with scintillating bolometers. The detector, consisting of 24 enriched and 2 natural ZnSe crystals, has been taking data at Laboratori Nazionali del Gran Sasso from June 2017 to December 2018, collecting a ^{82}Se exposure of 5.29 kg×yr. In this Letter we present the phase-I results in the search for 0νDBD. We demonstrate that the technology implemented by CUPID-0 allows us to reach the lowest background for calorimetric experiments: (3.5_{-0.9}^{+1.0})×10^{-3} counts/(keV kg yr). Monitoring 3.88×10^{25} ^{82}Se nuclei×yr we reach a 90% credible interval median sensitivity of T_{1/2}^{0ν}>5.0×10^{24} yr and set the most stringent limit on the half-life of ^{82}Se 0νDBD: T_{1/2}^{0ν}>3.5×10^{24} yr (90% credible interval), corresponding to m_{ßß}<(311-638) meV depending on the nuclear matrix element calculations.

4.
Phys Rev Lett ; 123(26): 262501, 2019 Dec 31.
Artículo en Inglés | MEDLINE | ID: mdl-31951429

RESUMEN

We report on the measurement of the two-neutrino double-ß decay of ^{82}Se performed for the first time with cryogenic calorimeters, in the framework of the CUPID-0 experiment. With an exposure of 9.95 kg yr of Zn^{82}Se, we determine the two-neutrino double-ß decay half-life of ^{82}Se with an unprecedented precision level, T_{1/2}^{2ν}=[8.60±0.03(stat) _{-0.13}^{+0.19}(syst)]×10^{19} yr. The very high signal-to-background ratio, along with the detailed reconstruction of the background sources allowed us to identify the single state dominance as the underlying mechanism of such a process, demonstrating that the higher state dominance hypothesis is disfavored at the level of 5.5σ.

5.
Phys Rev Lett ; 120(23): 232502, 2018 Jun 08.
Artículo en Inglés | MEDLINE | ID: mdl-29932707

RESUMEN

We report the result of the search for neutrinoless double beta decay of ^{82}Se obtained with CUPID-0, the first large array of scintillating Zn^{82}Se cryogenic calorimeters implementing particle identification. We observe no signal in a 1.83 kg yr ^{82}Se exposure, and we set the most stringent lower limit on the 0νßß ^{82}Se half-life T_{1/2}^{0ν}>2.4×10^{24} yr (90% credible interval), which corresponds to an effective Majorana neutrino mass m_{ßß}<(376-770) meV depending on the nuclear matrix element calculations. The heat-light readout provides a powerful tool for the rejection of α particles and allows us to suppress the background in the region of interest down to (3.6_{-1.4}^{+1.9})×10^{-3} counts/(keV kg yr), an unprecedented level for this technique.

6.
Eur Phys J C Part Fields ; 81(8): 722, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34720725

RESUMEN

Localization and modeling of radioactive contaminations is a challenge that ultra-low background experiments are constantly facing. These are fundamental steps both to extract scientific results and to further reduce the background of the detectors. Here we present an innovative technique based on the analysis of α - α delayed coincidences in 232 Th and 238 U decay chains, developed to investigate the contaminations of the ZnSe crystals in the CUPID-0 experiment. This method allows to disentangle surface and bulk contaminations of the detectors relying on the different probability to tag delayed coincidences as function of the α decay position.

7.
Eur Phys J C Part Fields ; 78(11): 888, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30881205

RESUMEN

The CUPID-0 experiment searches for double beta decay using cryogenic calorimeters with double (heat and light) read-out. The detector, consisting of 24 ZnSe crystals 95 % enriched in 82 Se and two natural ZnSe crystals, started data-taking in 2017 at Laboratori Nazionali del Gran Sasso. We present the search for the neutrino-less double beta decay of 82 Se into the 0 1 + , 2 1 + and 2 2 + excited states of 82 Kr with an exposure of 5.74 kg · yr (2.24 × 10 25  emitters · yr). We found no evidence of the decays and set the most stringent limits on the widths of these processes: Γ ( 82 Se → 82 Kr 0 1 + )8.55 × 10 - 24  yr - 1 , Γ ( 82 Se → 82 Kr 2 1 + ) < 6.25 × 10 - 24  yr - 1 , Γ ( 82 Se → 82 Kr 2 2 + )8.25 × 10 - 24  yr - 1 (90 % credible interval).

8.
Eur Phys J C Part Fields ; 78(9): 734, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30839752

RESUMEN

The suppression of spurious events in the region of interest for neutrinoless double beta decay will play a major role in next generation experiments. The background of detectors based on the technology of cryogenic calorimeters is expected to be dominated by α particles, that could be disentangled from double beta decay signals by exploiting the difference in the emission of the scintillation light. CUPID-0, an array of enriched Zn 82 Se scintillating calorimeters, is the first large mass demonstrator of this technology. The detector started data-taking in 2017 at the Laboratori Nazionali del Gran Sasso with the aim of proving that dual read-out of light and heat allows for an efficient suppression of the α background. In this paper we describe the software tools we developed for the analysis of scintillating calorimeters and we demonstrate that this technology allows to reach an unprecedented background for cryogenic calorimeters.

9.
Eur Phys J C Part Fields ; 78(5): 428, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-30996670

RESUMEN

The CUPID-0 detector hosted at the Laboratori Nazionali del Gran Sasso, Italy, is the first large array of enriched scintillating cryogenic detectors for the investigation of 82 Se neutrinoless double-beta decay ( 0 ν ß ß ). CUPID-0 aims at measuring a background index in the region of interest (RoI) for 0 ν ß ß at the level of 10 - 3  counts/(keV kg years), the lowest value ever measured using cryogenic detectors. CUPID-0 operates an array of Zn 82 Se scintillating bolometers coupled with bolometric light detectors, with a state of the art technology for background suppression and thorough protocols and procedures for the detector preparation and construction. In this paper, the different phases of the detector design and construction will be presented, from the material selection (for the absorber production) to the new and innovative detector structure. The successful construction of the detector lead to promising preliminary detector performance which is discussed here.

10.
Eur Phys J C Part Fields ; 76(7): 364, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-28280442

RESUMEN

The R&D activity performed during the last years proved the potential of ZnSe scintillating bolometers to the search for neutrino-less double beta decay, motivating the realization of the first large-mass experiment based on this technology: CUPID-0. The isotopic enrichment in [Formula: see text]Se, the Zn[Formula: see text]Se crystals growth, as well as the light detectors production have been accomplished, and the experiment is now in construction at Laboratori Nazionali del Gran Sasso (Italy). In this paper we present the results obtained testing the first three Zn[Formula: see text]Se crystals operated as scintillating bolometers, and we prove that their performance in terms of energy resolution, background rejection capability and intrinsic radio-purity complies with the requirements of CUPID-0.

11.
J Ultrasound ; 15(1): 16-9, 2012 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23396940

RESUMEN

PURPOSE: To characterize the rotator cable high-resolution ultrasound appearance in asymptomatic shoulders of volunteers of different age. MATERIALS AND METHODS: IRB approval and volunteers' written consent was obtained. Excluding subjects with known shoulder affections, we screened 24 asymptomatic volunteers. Supraspinatus and infraspinatus tendons high-resolution ultrasound evaluation was performed according to standard scan protocols, further excluding shoulders with partial/full-thickness cuff tears. Thus, we studied 24 shoulders in 12 young volunteers (age range 21-39 years, mean age 33 ± 8 years) and 21 shoulders in 11 elderly volunteers (age range 62-83 years, mean age 75 ± 45 years). For each shoulder, we noted rotator cable visibility and its thickness and width. Fisher's and U Mann-Whitney statistics were used. RESULTS: Rotator cable was less frequently detected in young than in elderly volunteers (5/24 vs. 11/21 shoulders; P = 0.034). When detected, rotator cable was significantly thicker in young (range 1.2-1.5 mm, mean thickness 1.3 ± 0.1 mm) than in elderly (range 0.9-1.4 mm, mean thickness 1.2 ± 0.1 mm) volunteers (P = 0.025), while its width was not significantly different in young (range 4.5-7.1 mm, mean 5.6 ± 1.1 mm) compared to elderly (range 2.5-7.1 mm, mean 4.2 ± 1.4 mm) volunteers (P = 0.074) although a tendency can be highlighted. CONCLUSIONS: Ultrasound demonstrated the different consistency of rotator cable in young and elderly asymptomatic patients, with high interobserver reproducibility.

12.
J Ultrasound ; 15(4): 267-72, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23730393

RESUMEN

Thanks to its intrinsic high spatial resolution, ultrasound is an ideal imaging modality for examining very thin, superficial structures, and this makes it very helpful in the evaluation of extrinsic carpal ligaments. These structures, which arise from the radius and ulna and insert on the carpal bones, are extremely important for wrist stability. Previous studies have assessed the use of ultrasound to study the extrinsic carpal ligaments in cadavers, healthy asymptomatic subjects, and patients with rheumatoid arthritis. In the present report, we review the normal anatomy, biomechanics, and ultrasound appearance of these ligaments.

13.
J Ultrasound ; 15(4): 260-6, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23730392

RESUMEN

PURPOSE: The efficacy of platelet-rich plasma (PRP) in the treatment and healing of chronic tendinopathy through stimulation of cell proliferation and total collagen production has been demonstrated by both in vitro and in vivo studies. The aim of this study is to evaluate the effectiveness of ultrasound (US)-guided autologous PRP injections in patellar and Achilles tendinopathy. MATERIALS AND METHODS: Autologous PRP was injected under US-guidance into the Achilles and patellar tendons (30 Achilles tendons, 28 patellar tendons) in 48 prospectively selected patients (30 males, 18 females, mean age 38 ± 16 years, range 20-61 years). All patients were previously evaluated according to the Victoria Institute of Sport Assessment (VISA) scale, which assessed pain and activity level, and they all underwent US of the tendon before treatment and at follow-up after 20 days and 6 months. Statistical analysis was performed with Chi-square and Wilcoxon tests. RESULTS: 20 days after PRP injection the patients presented a non-significant improvement of clinical symptoms. At the 6-month follow-up VISA score increased from a mean value of 57-75.5 (p < .01). US evaluation revealed a reduction of hypoechoic areas in 26 tendons (p < .01) associated with a widespread improvement of fibrillar echotexture of the tendon and reduced hypervascularity at power Doppler. CONCLUSION: PRP injection in patellar and Achilles tendinopathy results in a significant and lasting improvement of clinical symptoms and leads to recovery of the tendon matrix potentially helping to prevent degenerative lesions. US-guidance allows PRP injection into the tendon with great accuracy.

14.
Epilepsia ; 25(2): 161-7, 1984 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-6705746

RESUMEN

Sixteen subjects affected by Lennox-Gastaut syndrome (11 males and five females, ranging from 5 to 15 years of age [mean age, 9 years 11 months]) were followed for periods of 9 months to 5 years 9 months, and were studied during three to five prolonged hospitalizations for total periods of 2-9 months with a veiw to examining the distribution of epileptic seizures during four states of vigilance, evaluated from a behavioral point of view: sleep, drowsiness, inactive wakefulness, and active wakefulness. it was ascertained that the overall average of 406 seizures daily, directly observed, was distributed as follows: 26 (6.40%) during sleep; 128 (31.52%) during drowsiness; 219 (53.94%) during inactive wakefulness; and 33 (8.12%) during active wakefulness. The comparison between the incidence of seizures observed during active wakefulness and those observed during both drowsiness and inactive wakefulness was significant (p less than 0.001). The latter two states represent, in our study, the shortest period of the day (8 h as compared with the 16 h of sleep and active wakefulness), thus making the results of the comparison even more significant. The results of this study suggest the importance of a stimulating environment for children affected by Lennox-Gastaut syndrome, and they point out that an overdose of antiepileptic drugs, not uncommon in the treatment of this syndrome, may make seizures more frequent.


Asunto(s)
Epilepsia/fisiopatología , Adolescente , Niño , Preescolar , Femenino , Humanos , Masculino , Convulsiones/fisiopatología , Sueño/fisiología , Factores de Tiempo , Vigilia/fisiología
15.
In. Varma, Avnish K; Kowalski, Luiz Paulo; Herter, Nilton T. Oral oncology. New Delhi, MACMILLAN, 2002. p.16-21, graf, CD-ROM. (UICC).
Monografía en Inglés | LILACS, BBO | ID: biblio-871975
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