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2.
Phys Rev Lett ; 129(22): 222501, 2022 Nov 23.
Artículo en Inglés | MEDLINE | ID: mdl-36493444

RESUMEN

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.


Asunto(s)
Granisetrón , Semivida , Teorema de Bayes
3.
Phys Rev Lett ; 126(17): 171801, 2021 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-33988435

RESUMEN

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.

4.
Phys Rev Lett ; 124(12): 122501, 2020 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-32281829

RESUMEN

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.

5.
Phys Rev Lett ; 120(13): 132501, 2018 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-29694201

RESUMEN

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.

6.
Phys Rev Lett ; 115(10): 102502, 2015 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-26382673

RESUMEN

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.

9.
Riv Patol Nerv Ment ; 99(4): 195-206, 1978.
Artículo en Italiano | MEDLINE | ID: mdl-752181

RESUMEN

A case of Progressive Supranuclear Palsy (P.S.P.) of early onset (38 years) is described, with somewhat atypical features: the patient was oligophrenic, had no pseudobulbar signs, but there was some muscular atrophy, particularly of the shoulders girdle. On examination there was a slight cortical and cerebellar atrophy on the air encephalogram. Electromyography showed signs of damage to the lower motor neurone which was confirmed by muscular biopsy. In the literature a muscular atrophy in association with P.S.P. is rarely reported clinically although in some cases studied histologically there was degeneration in the nuclei of the cranial and spinal motor nerves. The present case may be an example of such widespread degeneration.


Asunto(s)
Parálisis Bulbar Progresiva/complicaciones , Atrofia Muscular/etiología , Atrofia , Parálisis Bulbar Progresiva/patología , Enfermedades Cerebelosas/complicaciones , Enfermedades Cerebelosas/patología , Femenino , Humanos , Discapacidad Intelectual , Persona de Mediana Edad , Neuronas Motoras/patología , Atrofia Muscular/patología
10.
Arthropod Struct Dev ; 31(4): 313-27, 2003 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-18088989

RESUMEN

The morphology and the ultrastructure of the male accessory glands and ejaculatory duct of Ceratitis capitata were investigated. There are two types of glands in the reproductive apparatus. The first is a pair of long, mesoderm-derived tubules with binucleate, microvillate secretory cells, which contain smooth endoplasmic reticulum and, in the sexually mature males, enlarged polymorphic mitochondria. The narrow lumen of the gland is filled with dense or sometimes granulated secretion, containing lipids. The second type consists of short ectoderm-derived glands, finger-like or claviform shaped. Despite the different shape of these glands, after a cycle of maturation, their epithelial cells share a large subcuticular cavity filled with electron-transparent secretion. The ejaculatory duct, lined by cuticle, has epithelial cells with a limited involvement in secretory activity. Electrophoretic analysis of accessory gland secretion reveals different protein profiles for long tubular and short glands with bands of 16 and 10kDa in both types of glands. We demonstrate that a large amount of accessory gland secretion is depleted from the glands after 30min of copulation.

11.
Radiol Med ; 87(1-2): 111-7, 1994.
Artículo en Italiano | MEDLINE | ID: mdl-8128012

RESUMEN

Neonatal adrenal gland hemorrhage is not uncommon. Its etiology is still questionable, though hypoxia (antenatal, labor-induced, or neonatal) seems to be usually associated with the event. Symptoms include acute shock associated with severe blood loss. Milder cases exhibit anemia and jaundice associated with a suprarenal mass. Ultrasonography (US) has replaced urography in the diagnosis of this condition, demonstrating site and size of the lesion and allowing an accurate follow-up. The authors report on a series of 11 patients; US was performed on 9 of them. In 10 cases the lesion was unilateral and in one case bilateral. Antenatal US diagnosis was possible in 2 cases and confirmed neonatally. The extant 9 infants developed a palpable abdominal mass or were diagnosed while examined for other conditions. All cases were evident by the 2nd week of life. Eight patients exhibited spontaneous hemorrhage resolution, as shown by repeated US and/or urographic exams. Three patients underwent surgery because the lesion seemed stable. In these 3 instances, CT scans were inconclusive. This paper is aimed at reporting on the radiologic and US features we observed, with a special emphasis on the changes in size, shape and US features in the cases which resolved spontaneously. The first US examination is not conclusive and does not allow an unquestionable differential diagnosis. Only lesion evolution with progressive decrease in its size (changes in US features are less useful) allows unquestionable US diagnosis and prevents unnecessary surgery.


Asunto(s)
Enfermedades de las Glándulas Suprarrenales/diagnóstico por imagen , Hemorragia/diagnóstico por imagen , Enfermedades de las Glándulas Suprarrenales/cirugía , Glándulas Suprarrenales/diagnóstico por imagen , Glándulas Suprarrenales/cirugía , Diagnóstico Diferencial , Femenino , Hemorragia/cirugía , Humanos , Recién Nacido , Masculino , Remisión Espontánea , Factores de Tiempo , Ultrasonografía
12.
Boll Soc Ital Biol Sper ; 65(5): 473-80, 1989 May.
Artículo en Italiano | MEDLINE | ID: mdl-2775553

RESUMEN

Serum values of retinol, carotenoids, tocopherol and ascorbic acid were assayed in healthy adult females (Group A: 20 cases) and in subjects with fibrocistic mastopathy (Group B: 20 cases), benign breast neoplasms, as fibroadenomas and intraductal papillomas (Group C: 18 cases), and breast carcinoma in situ (Group D: 36 cases). Retinol and carotenoids were evaluated by spectrophotometry using trifluoroacetic acid. Tocopherol was determined by a colorimetric method involving the reduction of Fe to Fe++ by tocopherol with the formation of a red complex of the Fe++ with alpha, alpha'-dipirydyl. Ascorbic acid was estimated by a colorimetric method after derivatization with 2,4-dinitrophenylhydrazine. Our results point out that there is a highly significant decrease (p less than 0.001) of average retinol serum levels in all three patient groups as compared with group A, whereas carotenoids resulted decreased but not significantly. Tocopherol was found to be significantly lower only in groups B (p less than 0.05) and D (p less than 0.01), ascorbic acid in groups B (p less than 0.01) C (p less than 0.05) and D (p less than 0.001).


Asunto(s)
Neoplasias de la Mama/sangre , Carotenoides/sangre , Vitaminas/sangre , Adenoma/sangre , Carcinoma in Situ/sangre , Femenino , Enfermedad Fibroquística de la Mama/sangre , Fibroma/sangre , Humanos , Papiloma/sangre , Deficiencia de Vitamina A/complicaciones
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