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1.
Phys Rev Lett ; 131(16): 162501, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37925694

RESUMO

Neutrinoless double beta decay (0νßß) is a yet unobserved nuclear process that would demonstrate Lepton number violation, a clear evidence of beyond standard model physics. The process two neutrino double beta decay (2νßß) is allowed by the standard model and has been measured in numerous experiments. In this Letter, we report a measurement of 2νßß decay half-life of ^{100}Mo to the ground state of ^{100}Ru of [7.07±0.02(stat)±0.11(syst)]×10^{18} yr by the CUPID-Mo experiment. With a relative precision of ±1.6% this is the most precise measurement to date of a 2νßß decay rate in ^{100}Mo. In addition, we constrain higher-order corrections to the spectral shape, which provides complementary nuclear structure information. We report a novel measurement of the shape factor ξ_{3,1}=0.45±0.03(stat)±0.05(syst) based on a constraint on the ratio of higher-order terms from theory, which can be reliably calculated. This is compared to theoretical predictions for different nuclear models. We also extract the first value for the effective axial vector coupling constant obtained from a spectral shape study of 2νßß decay.

3.
Phys Rev Lett ; 131(22): 222501, 2023 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-38101385

RESUMO

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.

4.
Phys Rev Lett ; 129(22): 222501, 2022 Nov 23.
Artigo em Inglês | MEDLINE | ID: mdl-36493444

RESUMO

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.


Assuntos
Granisetron , Meia-Vida , Teorema de Bayes
5.
Phys Rev Lett ; 129(11): 111801, 2022 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-36154394

RESUMO

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.

6.
Phys Rev Lett ; 126(18): 181802, 2021 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-34018798

RESUMO

The CUPID-Mo experiment at the Laboratoire Souterrain de Modane (France) is a demonstrator for CUPID, the next-generation ton-scale bolometric 0νßß experiment. It consists of a 4.2 kg array of 20 enriched Li_{2}^{100}MoO_{4} scintillating bolometers to search for the lepton-number-violating process of 0νßß decay in ^{100}Mo. With more than one year of operation (^{100}Mo exposure of 1.17 kg×yr for physics data), no event in the region of interest and, hence, no evidence for 0νßß is observed. We report a new limit on the half-life of 0νßß decay in ^{100}Mo of T_{1/2}>1.5×10^{24} yr at 90% C.I. The limit corresponds to an effective Majorana neutrino mass ⟨m_{ßß}⟩<(0.31-0.54) eV, dependent on the nuclear matrix element in the light Majorana neutrino exchange interpretation.

7.
Phys Rev Lett ; 126(17): 171801, 2021 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-33988435

RESUMO

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.

8.
Phys Rev Lett ; 124(12): 122501, 2020 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-32281829

RESUMO

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.

9.
Phys Rev Lett ; 123(3): 032501, 2019 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-31386478

RESUMO

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.

10.
Phys Rev Lett ; 123(26): 262501, 2019 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-31951429

RESUMO

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.

11.
Phys Rev Lett ; 120(23): 232502, 2018 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-29932707

RESUMO

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.

12.
Phys Rev Lett ; 120(13): 132501, 2018 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-29694201

RESUMO

The CUORE experiment, a ton-scale cryogenic bolometer array, recently began operation at the Laboratori Nazionali del Gran Sasso in Italy. The array represents a significant advancement in this technology, and in this work we apply it for the first time to a high-sensitivity search for a lepton-number-violating process: ^{130}Te neutrinoless double-beta decay. Examining a total TeO_{2} exposure of 86.3 kg yr, characterized by an effective energy resolution of (7.7±0.5) keV FWHM and a background in the region of interest of (0.014±0.002) counts/(keV kg yr), we find no evidence for neutrinoless double-beta decay. Including systematic uncertainties, we place a lower limit on the decay half-life of T_{1/2}^{0ν}(^{130}Te)>1.3×10^{25} yr (90% C.L.); the median statistical sensitivity of this search is 7.0×10^{24} yr. Combining this result with those of two earlier experiments, Cuoricino and CUORE-0, we find T_{1/2}^{0ν}(^{130}Te)>1.5×10^{25} yr (90% C.L.), which is the most stringent limit to date on this decay. Interpreting this result as a limit on the effective Majorana neutrino mass, we find m_{ßß}<(110-520) meV, where the range reflects the nuclear matrix element estimates employed.

13.
J Endocrinol Invest ; 41(8): 929-936, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-29302920

RESUMO

PURPOSE: Few examples of the involvement of a single gene in idiopathic short stature have been described until now. Our aim was to identify the causative gene of proportionate short stature in a large family showing co-segregation of the phenotype with the reciprocal translocation t(10;15)(q22;q24). METHODS: FISH mapping was carried out with BACs and long-range PCR probes to identify the smallest genomic regions harboring the translocation breakpoints. Real-Time RT-PCR was performed in blood after pre-amplification of target genes cDNA. RESULT: The affected family members presented with a final height of between - 2.41 and - 4.18 SDS and very mild skeletal dysmorphisms. Growth rates of the proband and of her cousin, whose childhood and pre-pubertal bone age corresponded to the chronological age, showed a poor growth spurt during treatment with rhGH. However, their adult height was greater than that of their untreated mothers, suggesting efficacy of GH therapy. Breakpoint mapping revealed that the translocation t(10;15)(q22.3;q26.1) disrupts, on 15q, the ACAN gene at intron 1, decreasing its transcriptional expression. CONCLUSIONS: This is the first description of a chromosome rearrangement disrupting ACAN and leading to its haploinsufficiency. ACAN loss of function should be considered a potential underpinning of short patients who display a poor growth spurt and belong to families with autosomal dominant segregation of proportionate short stature. Besides this core phenotype, literature review suggests that advanced bone age, early onset osteochondritis dissecans, osteoarthritis, intervertebral disc disease as well as craniofacial dysmorphisms can be important suggestive phenotypes in affected families.


Assuntos
Cromossomos Humanos Par 10/genética , Cromossomos Humanos Par 15/genética , Nanismo/genética , Translocação Genética , Adolescente , Adulto , Agrecanas , Criança , Nanismo/patologia , Feminino , Seguimentos , Humanos , Masculino , Pessoa de Meia-Idade , Linhagem , Fenótipo , Prognóstico , Adulto Jovem
14.
Phys Rev Lett ; 115(10): 102502, 2015 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-26382673

RESUMO

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.

15.
Pulm Pharmacol Ther ; 27(2): 129-38, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24468677

RESUMO

Randomized Controlled Trials (RCTs) are the "gold standard" for evaluating treatment outcomes providing information on treatments "efficacy". They are designed to test a therapeutic hypothesis under optimal setting in the absence of confounding factors. For this reason they have high internal validity. The strict and controlled conditions in which they are conducted, leads to low generalizability because they are performed in conditions very different from real life usual care. Conversely, real life studies inform on the "effectiveness" of a treatment, that is, the measure of the extent to which an intervention does what is intended to do in routine circumstances. At variance to RCTs, real life trials have high generalizability, but low internal validity. Recently the number of real life studies has been rapidly growing in different areas of respiratory medicine, particularly in asthma and COPD. The role of such studies is becoming a hot topic in respiratory medicine, attracting research interest and debate. In the first part of this review we discuss some of the advantages and disadvantages of different types of RCTs and analyze the strengths and weaknesses of real life trials, considering the recent examples of some studies conducted in COPD. We then discuss methodological approaches and options to overcome some of the limitations of real life studies. Comparing the conclusions of effectiveness and efficacy trials can provide important pieces of information. Indeed, these approaches can result complementary, and they can guide the interpretation of each other results.


Assuntos
Doença Pulmonar Obstrutiva Crônica/terapia , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Projetos de Pesquisa , Asma/terapia , Fatores de Confusão Epidemiológicos , Humanos
16.
Eur Ann Allergy Clin Immunol ; 46(3): 100-5, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24853567

RESUMO

Oral food challenge (OFC) is still considered the gold standard for diagnosis of food allergy (FA). Skin prick test (SPT) and specific IgE (sIgE) tests are very useful but limited in their predictive accuracy. End point test (EPT) has been recently considered to determine the starting dose to induce oral desensitization. Allergometric tests combined may discriminate children at higher risk of reactions during OFC. We considered 94 children referred to our Allergy and Immunology Pediatric Department between January 2009 and December 2011 with CMA. Cutaneous allergometric skin tests (SPT and EPT) were periodically performed on all 94 children with CMA; sIgE levels against cow's milk proteins (CMP) α-lactalbumin, ß-lactoglobulin and casein were periodically evaluated through blood samples every 6-12 months. During the period of the study, 26/94 (27.6%) children underwent more than once OFC. We collected 135 OFC compared with clinical presentation: 49/135 (36.2%) OFC were performed shortly after the onset of symptoms directly related to spontaneous intake of milk, to confirm suspicion of FA; 86/135 (63.7%) OFC were performed to evaluate the acquisition of tolerance. Of these, 52/86 (60.4%) OFC resulted positive, 34/86 (39.5%) were negative. The 3D EPT has the best ratio sensitivity (SE) / positive predictive value (PPV), SE 83%, specificity (SP) 58.3%, PPV 89.3%, negative predictive value (NPV) 45.1%. EPT 6D and 7D have the best PPV (100%) with a low NPV (respectively 22.2% and 21.2%). We obtained that a mean fresh milk wheal diameter ≥ 12 mm was predictive of 97% OFC, but only 32/101 (31.6%) allergic children presented this value. The tests with a wheal diameter ≤ 5 were performed on younger children, all of which were less than 9 months old; only 5 other tests performed on less than 9 months olds resulted in the others subgroups (1 in ≥ 12 mm wheal and 4 in the group between 6-11 mm). We also found that 95% of children with 4D EPT wheal diameter < 6 mm resulted tolerant. This cut off could be useful to decide which children have a lower risk of reactions during the OFC. EPT is more useful than SPT especially for children < 1 year of age being a less operator dependent test, and it could be helpful to discriminate between children with the highest risk to develop anaphylaxis following an OFC (≥ 5D positive EPT) and children with lowest risk (> 2D positive EPT), but it can't replace OFC, that currently remains the gold standard in the diagnosis of FA. We also underline that in allergic children younger than 9 months old, the values of SPT with fresh milk is much lower than in older children, so that it's better to separate this group of age when we try to predict the evolution of OFC through the evaluation with EPT. A validation of such results in a prospective study could maybe be useful to confirm the outcome of our data in the predictivity of OFC.


Assuntos
Dermatite Atópica/diagnóstico , Imunoglobulina E/sangue , Testes Intradérmicos , Hipersensibilidade a Leite/diagnóstico , Proteínas do Leite/imunologia , Fatores Etários , Anafilaxia/imunologia , Biomarcadores/sangue , Caseínas/imunologia , Dermatite Atópica/imunologia , Determinação de Ponto Final , Humanos , Lactente , Lactalbumina/imunologia , Lactoglobulinas/imunologia , Hipersensibilidade a Leite/sangue , Hipersensibilidade a Leite/imunologia , Valor Preditivo dos Testes , Fatores de Risco , Índice de Gravidade de Doença , Fatores de Tempo
17.
Eur Phys J C Part Fields ; 81(8): 722, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34720725

RESUMO

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.

18.
Epidemiol Psychiatr Sci ; 29: e27, 2019 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-30968810

RESUMO

AIMS: First-episode psychosis (FEP) is a major life event and can have an adverse impact on the diagnosed individual and their families. The importance of intervening early and providing optimal treatments is widely acknowledged. In comparison to patient groups, literature is scarce on identifying treatment predictors and moderators of caregiver outcomes. This study aimed to identify pre-treatment characteristics predicting and/or moderating carer outcomes, based on data from a multi-element psychosocial intervention to FEP patients and carers (GET-UP PIANO trial). METHODS: Carer demography, type of family relationship, patient contact hours, pre-treatment carer burden, patient perceptions of parental caregiving and expressed emotion (EE) were selected, a priori, as potential predictors/moderators of carer burden and emotional distress at 9 months post treatment. Outcomes were analysed separately in mixed-effects random regression models. RESULTS: Analyses were performed on 260 carers. Only patient perceptions of early maternal criticism predicted reports of lower carer burden at follow-up. However, multiple imputation analysis failed to confirm this result. For treatment moderators: higher levels of carer burden at baseline yielded greater reductions in carer emotional distress at follow-up in the experimental group compared with treatment as usual (TAU). Higher levels of perceived EE moderated greater reductions in carer reports of tension in experimental group, compared with TAU, at follow-up. In younger caregivers (<51 years old), there were greater reductions in levels of worry during the baseline to follow-up period, within the experimental group compared with TAU. CONCLUSION: The study failed to identify significant treatment predictors of FEP carer outcomes. However, our preliminary findings suggest that optimal treatment outcomes for carers at first episode might be moderated by younger carer age, and carers reporting higher baseline levels of burden, and where patients perceive higher levels of negative effect from caregivers.


Assuntos
Cuidadores/psicologia , Efeitos Psicossociais da Doença , Angústia Psicológica , Transtornos Psicóticos/psicologia , Transtornos Psicóticos/terapia , Cuidadores/estatística & dados numéricos , Análise por Conglomerados , Emoções Manifestas , Feminino , Humanos , Itália , Masculino , Pessoa de Meia-Idade
19.
Eur Phys J C Part Fields ; 78(11): 888, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30881205

RESUMO

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).

20.
Eur Phys J C Part Fields ; 78(9): 734, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30839752

RESUMO

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.

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