532 research outputs found

    Pulse Shape Analysis with scintillating bolometers

    Full text link
    Among the detectors used for rare event searches, such as neutrinoless Double Beta Decay (0ν\nuDBD) and Dark Matter experiments, bolometers are very promising because of their favorable properties (excellent energy resolution, high detector efficiency, a wide choice of different materials used as absorber, ...). However, up to now, the actual interesting possibility to identify the interacting particle, and thus to greatly reduce the background, can be fulfilled only with a double read-out (i.e. the simultaneous and independent read out of heat and scintillation light or heat and ionization). This double read-out could greatly complicate the assembly of a huge, multi-detector array, such as CUORE and EURECA. The possibility to recognize the interacting particle through the shape of the thermal pulse is then clearly a very interesting opportunity. While detailed analyses of the signal time development in purely thermal detectors have not produced so far interesting results, similar analyses on macro-bolometers (∼\sim10-500 g) built with scintillating crystals showed that it is possible to distinguish between an electron or γ\gamma-ray and an α\alpha particle interaction (i.e. the main source of background for 0ν\nuDBD experiments based on the bolometric technique). Results on pulse shape analysis of a CaMoO4_4 crystal operated as bolometer is reported as an example. An explanation of this behavior, based on the energy partition in the heat and scintillation channels, is also presented.Comment: Presented at the 14th International Workshop on Low Temperature Detectors, proceedings to be published in the Journal of Low Temperature Physic

    Nicotinamide and calcipotriol counteract UVB-induced photoaging on primary human dermal fibroblasts

    Get PDF
    Background: Photoaging is mainly caused by ultraviolet radiations inasmuch they can damage the DNA, trigger ROS production, and activate p53/p21 pathway, which cause cell cycle arrest and senescence. The accumulationof senescent cells within the dermis contributes to tissue deregulation and skin carcinogenesis. However, the use of photoprotector molecules could reduce UV-induced damages and prevent photoaging. Therefore, the aim of this study is to evaluate whether the active forms of vitamin B3 (nicotinamide) and the analog of vitamin D3 (calcipotriol) might protect primary human dermal fibroblasts (HDFs) from UVB-induced photoaging. Methods: HDFs were isolated from a healthy adult donor and stimulated with nicotinamide (25 μM) and calcipotriol (100 nM) for 24h before UVB exposure, and then, cultured for further 24h on vitamin-supplemented media. Then, cell viability, ROS production, DNA damages, senescence markers, protein and gene expression were evaluated. Results: HDFs treated with nicotinamide and calcipotriol showed better proliferation properties and lower DNA damages due to a reduced UVB-induced ROS production. Consequently, p53/p21 pathway was less active which enhanced cell cycle progression and reduced senescence and cell death. Conclusions: Overall, our results suggest that nicotinamide and calcipotriol can counteract UVB-induced effects responsible for the onset of skin photoaging

    Tetracyclines in COVID-19 patients quarantined at home: Literature evidence supporting real-world data from a multicenter observational study targeting inflammatory and infectious dermatoses

    Get PDF
    Tetracyclines (TetraC) are widely used in dermatology for both inflammatory and infectious dermatoses; recently both in vivo and in vitro studies started to suggest also a potential antiviral effect. During COVID-19 outbreak, several dermatological patients contracted SARS-CoV-2 experiencing only mild symptoms, but no protocol were approved. A multicenter prospective observational study that enrolled COVID-19 patients visited with teledermatology and undergoing TetraC was performed. About 38 adult outpatients (M/F: 20/18, age 42.6 years [21-67]) were enrolled. During the TetraC treatment, symptoms resolved in all patients within 10 days. Remarkably, ageusia and anosmia disappeared in the first week of TetraC treatment. TetraC seem a promising drug to treat COVID-19 outpatients with mild symptoms

    Development of a Li2MoO4 scintillating bolometer for low background physics

    Full text link
    We present the performance of a 33 g Li2MoO4 crystal working as a scintillating bolometer. The crystal was tested for more than 400 h in a dilution refrigerator installed in the underground laboratory of Laboratori Nazionali del Gran Sasso (Italy). This compound shows promising features in the frame of neutron detection, dark matter search (solar axions) and neutrinoless double-beta decay physics. Low temperature scintillating properties were investigated by means of different alpha, beta/gamma and neutron sources, and for the first time the Light Yield for different types of interacting particle is estimated. The detector shows great ability of tagging fast neutron interactions and high intrinsic radiopurity levels (< 90 \muBq/kg for 238-U and < 110 \muBq/kg for 232-Th).Comment: revised versio

    CUPID-0: the first array of enriched scintillating bolometers for 0decay investigations

    Get PDF
    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 of82Se neutrinoless double-beta decay (0). CUPID-0 aims at measuring a background index in the region of interest (RoI) for 0at the level of 10- 3 counts/(keV kg years), the lowest value ever measured using cryogenic detectors. CUPID-0 operates an array of Zn82Se 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

    Efficacy of intranasal virosomal influenza vaccine in the prevention of recurrent acute otitis media in children

    Get PDF
    To evaluate the efficacy of an intranasal, inactivated, virosomal subunit influenza vaccine for prevention of new episodes of acute otitis media (AOM) in children with recurrent AOM, 133 children aged 1-5 years were randomized to receive the vaccine (n=67) or no vaccination (n=66). During a 6-month period, 24 (35.8%) vaccine recipients had 32 episodes of AOM; 42 (63.6%) control subjects had 64 episodes. The overall efficacy of vaccination in preventing AOM was 43.7% (95% confidence interval, 18.6-61.1; P=.002). Children vaccinated before influenza season had a significantly better outcome than did those vaccinated after the onset of influenza season. The cumulative duration of middle ear effusion was significantly less in vaccinated children than in control subjects. Data suggest that the intranasal virosomal influenza vaccine might be considered among the options for the prevention of AOM in children <5 years old with recurrent AO

    First array of enriched Zn82^{82}Se bolometers to search for double beta decay

    Get PDF
    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 82^{82}Se, the Zn82^{82}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 Zn82^{82}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
    • …
    corecore