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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.
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Core-collapse Supernovae (SNe) are one of the most energetic events in the Universe, during which almost all the star's binding energy is released in the form of neutrinos. These particles are direct probes of the processes occurring in the stellar core and provide unique insights into the gravitational collapse. RES-NOVA will revolutionize how we detect neutrinos from astrophysical sources, by deploying the first ton-scale array of cryogenic detectors made from archaeological lead. Pb offers the highest neutrino interaction cross-section via coherent elastic neutrino-nucleus scattering (CEνNS). Such process will enable RES-NOVA to be equally sensitive to all neutrino flavours. For the first time, we propose the use archaeological Pb as sensitive target material in order to achieve an ultra-low background level in the region of interest (O(1 keV)). All these features make possible the deployment of the first cm-scale neutrino telescope for the investigation of astrophysical sources. In this contribution, we will characterize the radiopurity level and the performance of a small-scale proof-of-principle detector of RES-NOVA, consisting in a PbWO4 crystal made from archaeological-Pb operated as cryogenic detector.
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This corrects the article DOI: 10.1103/PhysRevLett.126.171801.
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The Cryogenic Underground Observatory for Rare Events (CUORE) at Laboratori Nazionali del Gran Sasso of INFN in Italy is an experiment searching for neutrinoless double beta (0νßß) decay. Its main goal is to investigate this decay in ^{130}Te, but its ton-scale mass and low background make CUORE sensitive to other rare processes as well. In this Letter, we present our first results on the search for 0νßß decay of ^{128}Te, the Te isotope with the second highest natural isotopic abundance. We find no evidence for this decay, and using a Bayesian analysis we set a lower limit on the ^{128}Te 0νßß decay half-life of T_{1/2}>3.6×10^{24} yr (90% CI). This represents the most stringent limit on the half-life of this isotope, improving by over a factor of 30 the previous direct search results, and exceeding those from geochemical experiments for the first time.
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Granisetron , Meia-Vida , Teorema de BayesRESUMO
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.
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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.
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We measured two-neutrino double beta decay of ^{130}Te using an exposure of 300.7 kg yr accumulated with the CUORE detector. Using a Bayesian analysis to fit simulated spectra to experimental data, it was possible to disentangle all the major background sources and precisely measure the two-neutrino contribution. The half-life is in agreement with past measurements with a strongly reduced uncertainty: T_{1/2}^{2ν}=7.71_{-0.06}^{+0.08}(stat)_{-0.15}^{+0.12}(syst)×10^{20} yr. This measurement is the most precise determination of the ^{130}Te 2νßß decay half-life to date.
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We report new results from the search for neutrinoless double-beta decay in ^{130} Te with the CUORE detector. This search benefits from a fourfold increase in exposure, lower trigger thresholds, and analysis improvements relative to our previous results. We observe a background of (1.38±0.07)×10^{-2} counts/(keV kg yr)) in the 0νßß decay region of interest and, with a total exposure of 372.5 kg yr, we attain a median exclusion sensitivity of 1.7×10^{25} yr. We find no evidence for 0νßß decay and set a 90% credibility interval Bayesian lower limit of 3.2×10^{25} yr on the ^{130} Te half-life for this process. In the hypothesis that 0νßß decay is mediated by light Majorana neutrinos, this results in an upper limit on the effective Majorana mass of 75-350 meV, depending on the nuclear matrix elements used.
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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.
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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.
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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.
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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.
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We report the results of a search for neutrinoless double-beta decay in a 9.8 kg yr exposure of (130)Te using a bolometric detector array, CUORE-0. The characteristic detector energy resolution and background level in the region of interest are 5.1±0.3 keV FWHM and 0.058±0.004(stat)±0.002(syst)counts/(keV kg yr), respectively. The median 90% C.L. lower-limit half-life sensitivity of the experiment is 2.9×10(24) yr and surpasses the sensitivity of previous searches. We find no evidence for neutrinoless double-beta decay of (130)Te and place a Bayesian lower bound on the decay half-life, T(1/2)(0ν)>2.7×10(24) yr at 90% C.L. Combining CUORE-0 data with the 19.75 kg yr exposure of (130)Te from the Cuoricino experiment we obtain T(1/2)(0ν)>4.0×10(24) yr at 90% C.L. (Bayesian), the most stringent limit to date on this half-life. Using a range of nuclear matrix element estimates we interpret this as a limit on the effective Majorana neutrino mass, m(ßß)<270-760 meV.
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Next-generation experiments searching for neutrinoless double-beta decay must be sensitive to a Majorana neutrino mass as low as 10[Formula: see text]. CUORE , an array of 988 TeO[Formula: see text] bolometers being commissioned at Laboratori Nazionali del Gran Sasso, features an expected sensitivity of 50-130[Formula: see text] at 90 % C.L. The background is expected to be dominated by [Formula: see text] radioactivity, and can be in principle removed by detecting the small amount of Cherenkov light emitted by the [Formula: see text] signal. The Cryogenic wide-Area Light Detectors with Excellent Resolution project aims at developing a small prototype experiment consisting of TeO[Formula: see text] bolometers coupled to high-sensitivity light detectors based on kinetic inductance detectors. The R&D is focused on the light detectors in view of the implementation in a next-generation neutrinoless double-beta decay experiment.
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CUORE, an array of 988 TeO[Formula: see text] bolometers, is about to be one of the most sensitive experiments searching for neutrinoless double-beta decay. Its sensitivity could be further improved by removing the background from [Formula: see text] radioactivity. A few years ago it was pointed out that the signal from [Formula: see text]s can be tagged by detecting the emitted Cherenkov light, which is not produced by [Formula: see text]s. In this paper we confirm this possibility. For the first time we measured the Cherenkov light emitted by a CUORE crystal, and found it to be 100 eV at the [Formula: see text]-value of the decay. To completely reject the [Formula: see text] background, we compute that one needs light detectors with baseline noise below 20 eV RMS, a value which is 3-4 times smaller than the average noise of the bolometric light detectors we are using. We point out that an improved light detector technology must be developed to obtain TeO[Formula: see text] bolometric experiments able to probe the inverted hierarchy of neutrino masses.
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The precise measurement of forces is one way to obtain deep insight into the fundamental interactions present in nature. In the context of neutral antimatter, the gravitational interaction is of high interest, potentially revealing new forces that violate the weak equivalence principle. Here we report on a successful extension of a tool from atom optics--the moiré deflectometer--for a measurement of the acceleration of slow antiprotons. The setup consists of two identical transmission gratings and a spatially resolving emulsion detector for antiproton annihilations. Absolute referencing of the observed antimatter pattern with a photon pattern experiencing no deflection allows the direct inference of forces present. The concept is also straightforwardly applicable to antihydrogen measurements as pursued by the AEgIS collaboration. The combination of these very different techniques from high energy and atomic physics opens a very promising route to the direct detection of the gravitational acceleration of neutral antimatter.
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BACKGROUND AND AIMS: Lifestyle changes are considered first line treatment in type 2 diabetes, but very few data are available in the "real world" of diabetes units. We aimed to measure the effectiveness of moderate and high intensity interventions on weight loss, metabolic control and insulin use. We report a prospective cohort study, carried out in 822 consecutive subjects with type 2 diabetes, first seen in a 4-year period in a diabetes unit of an academy hospital. METHODS AND RESULTS: Subjects were treated with either a sole prescriptive diet (Diet), or received an additional short-course Elementary Nutritional Education (4 group sessions-ENE) or an intensive Cognitive Behavioural Therapy (12-15 group sessions-CBT). The results were adjusted for the propensity score to be assigned different treatments, derived from logistic regression on the basis of age, gender, BMI, HbA1c, diabetes duration and insulin use at baseline. Main outcome measures were weight loss and weight loss maintenance, metabolic control, and secondary failure to insulin use. Both structured programmes produced a larger weight loss, and the adjusted probability of achieving the 7% weight loss target was increased. Similarly, both programmes favoured metabolic control, irrespective of insulin use. After adjustment for propensity score, both ENE (hazard ratio, 0.48; 95% CI, 0.27-0.84) and CBT (hazard ratio, 0.36; 95% CI, 0.16-0.83) were associated with a reduced risk of de novo insulin treatment. CONCLUSION: Structured behavioural programmes aimed at lifestyle changes are feasible and effective in the "real world" setting of a diabetes unit for the treatment of type 2 diabetes.
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Terapia Cognitivo-Comportamental , Diabetes Mellitus Tipo 2/terapia , Dieta Redutora , Exercício Físico/fisiologia , Ciências da Nutrição/educação , Índice de Massa Corporal , Estudos de Coortes , Diabetes Mellitus Tipo 2/dietoterapia , Diabetes Mellitus Tipo 2/tratamento farmacológico , Dieta para Diabéticos , Gerenciamento Clínico , Feminino , Seguimentos , Hemoglobinas Glicadas , Humanos , Hipoglicemiantes/uso terapêutico , Insulina/uso terapêutico , Estilo de Vida , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Resultado do Tratamento , Redução de Peso/fisiologiaRESUMO
Cognitive behavioural therapy (CBT) is the most comprehensive means of medically treating obesity, but only few data have so far been published concerning its long-term effectiveness. We here report our experience of 1068 consecutive patients (868 females) treated with CBT at a university-based obesity centre. The patients were enrolled into three different programmes: a 14-week LEARN programme (672 patients), a 16-week MOB programme for the morbidly obese (259 patients), or a 20-week BINGE programme for subjects affected by binge eating (137 patients). Eighty-five percent of the subjects completed the weekly programmes. The percentage of patients attending the scheduled control visits during the 1-year follow-up gradually decreased, being very low in the BINGE group (10%). The percentage weight loss was an average of 6% during the weekly courses, being higher in the MOB programme; by the end of the weekly sessions, it exceeded 10% of initial body weight in 22% of cases and increased to 36% during the follow-up. The cumulative probability of follow-up was higher among the patients undergoing the MOB and LEARN programmes than among the BINGE patients (p < 0.0001), and decreased with the increasing severity of obesity. Female gender and a weight loss of > 10% i.b.w. increased compliance to follow-up. The study further demonstrates the difficulty of achieving compliance to chronic management of obesity and the critical role of binge eating disorder in the medium-term treatment of obesity. Strategies are needed to improve adherence to a follow-up protocol.
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Bulimia/terapia , Terapia Cognitivo-Comportamental/métodos , Obesidade Mórbida/terapia , Obesidade/terapia , Adaptação Psicológica , Adulto , Análise de Variância , Índice de Massa Corporal , Bulimia/psicologia , Terapia Cognitivo-Comportamental/normas , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Motivação , Obesidade/psicologia , Obesidade Mórbida/psicologia , Equipe de Assistência ao Paciente , Cooperação do Paciente/psicologia , Educação de Pacientes como Assunto , Resolução de Problemas , Avaliação de Programas e Projetos de Saúde , Modelos de Riscos Proporcionais , Índice de Gravidade de Doença , Resultado do Tratamento , Redução de PesoRESUMO
OBJECTIVE: To measure the effects of cognitive-behavioural therapy on health-related quality of life (HRQL) in obese patients, in relation to binge eating disorder. DESIGN: Longitudinal, clinical intervention study consisting of structured sessions of cognitive-behavioural therapy, preceded by sessions chaired by a psychologist in subjects with binge eating. SUBJECTS: Two groups of obese patients (92 treated by cognitive-behavioural therapy (77 females); 76 untreated controls (67 female), selected from the waiting list (control group)). Of 92 treated patients, 46 had a binge eating disorder at psychometric testing and structured clinical interview. MEASUREMENTS: Health-related quality of life by means of Short-Form 36 questionnaire at baseline and after 3-5 months. RESULTS: Cognitive-behavioural treatment produced an average weight loss of 9.4+/-7.5 kg, corresponding to a BMI reduction of 3.48+/-2.70 kg/m(2). No changes were observed in the control group. All scales of HRQL improved in treated subjects (by 5-19%). In obese subjects with binge eating weight loss was lower in comparison to non-bingers (7.7+/-8.1 vs 11.1+/-6.6; P=0.034). However, the improvement in HRQL was on average larger, and significantly so for Role Limitation-Physical (P=0.006), Role Limitation-Emotional (P=0.002), Vitality (P=0.003), Mental Health (P=0.032) and Social Functioning (P=0.034). Bodily Pain was the sole scale whose changes paralleled changes in body weight. CONCLUSIONS: The positive effects of cognitive-behavioural therapy, mainly in subjects with binge eating, largely outweigh the effects on body weight, resulting in a significant change in self-perceived health status.