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1.
Phys Rev Lett ; 130(10): 101001, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36962014

RESUMEN

Dark matter elastic scattering off nuclei can result in the excitation and ionization of the recoiling atom through the so-called Migdal effect. The energy deposition from the ionization electron adds to the energy deposited by the recoiling nuclear system and allows for the detection of interactions of sub-GeV/c^{2} mass dark matter. We present new constraints for sub-GeV/c^{2} dark matter using the dual-phase liquid argon time projection chamber of the DarkSide-50 experiment with an exposure of (12 306±184) kg d. The analysis is based on the ionization signal alone and significantly enhances the sensitivity of DarkSide-50, enabling sensitivity to dark matter with masses down to 40 MeV/c^{2}. Furthermore, it sets the most stringent upper limit on the spin independent dark matter nucleon cross section for masses below 3.6 GeV/c^{2}.

2.
Phys Rev Lett ; 130(10): 101002, 2023 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-36962032

RESUMEN

We present a search for dark matter particles with sub-GeV/c^{2} masses whose interactions have final state electrons using the DarkSide-50 experiment's (12 306±184) kg d low-radioactivity liquid argon exposure. By analyzing the ionization signals, we exclude new parameter space for the dark matter-electron cross section σ[over ¯]_{e}, the axioelectric coupling constant g_{Ae}, and the dark photon kinetic mixing parameter κ. We also set the first dark matter direct-detection constraints on the mixing angle |U_{e4}|^{2} for keV/c^{2} sterile neutrinos.

3.
Clin Ter ; 173(4): 384-395, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35857058

RESUMEN

Aim: To investigate whether and how ten ethical principles are mentioned within documents on critical care resources allocation during public health emergencies. Materials and Methods: We conducted a search of documents con-cerning critical resources allocation during public emergencies publicly available from Google and two specific international websites, up to November 2020. Each document was analyzed by two independent reviewers to assess whether a reference to any of the 10 key ethical principles indicated by the Northern Italy Ethical Committee could be found in the documents. Cohen's K statistic was used. Results: We obtained 34 documents, of which 19 were allocation frameworks, 15 crisis standards of care, 4 clinical triage protocol, 3 clinical guidelines and 2 public health emergency response plans. The principles most frequently mentioned as important for decision-making was "number of lives saved", followed by "transparency", "equity", "respect of person and their autonomy". The most cited tiebreakers were "younger first/life cycle" and "lottery". Conclusions: All documents aim to protect the life and health of the largest number of people and should be objective, ethical, transparent, applied equitably, and be publicly disclosed. It is plausible that short- and long-term prognostic tools can help allocate critical resources, but it remains strong that the decision-making process must be guided by a multi-principle ethical model that is not always easy to apply.


Asunto(s)
Asignación de Recursos para la Atención de Salud , Salud Pública , Cuidados Críticos , Toma de Decisiones , Urgencias Médicas , Humanos , Pandemias , Triaje
4.
Phys Rev Lett ; 128(9): 091803, 2022 Mar 04.
Artículo en Inglés | MEDLINE | ID: mdl-35302807

RESUMEN

We report the measurement of sub-MeV solar neutrinos through the use of their associated Cherenkov radiation, performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The measurement is achieved using a novel technique that correlates individual photon hits of events to the known position of the Sun. In an energy window between 0.54 to 0.74 MeV, selected using the dominant scintillation light, we have measured 10 887_{-2103}^{+2386}(stat)±947(syst) (68% confidence interval) solar neutrinos out of 19 904 total events. This corresponds to a ^{7}Be neutrino interaction rate of 51.6_{-12.5}^{+13.9} counts/(day·100 ton), which is in agreement with the standard solar model predictions and the previous spectroscopic results of Borexino. The no-neutrino hypothesis can be excluded with >5σ confidence level. For the first time, we have demonstrated the possibility of utilizing the directional Cherenkov information for sub-MeV solar neutrinos, in a large-scale, high light yield liquid scintillator detector. This measurement provides an experimental proof of principle for future hybrid event reconstruction using both Cherenkov and scintillation signatures simultaneously.

5.
Phys Rev Lett ; 129(25): 252701, 2022 Dec 16.
Artículo en Inglés | MEDLINE | ID: mdl-36608219

RESUMEN

We present an improved measurement of the carbon-nitrogen-oxygen (CNO) solar neutrino interaction rate at Earth obtained with the complete Borexino Phase-III dataset. The measured rate, R_{CNO}=6.7_{-0.8}^{+2.0} counts/(day×100 tonnes), allows us to exclude the absence of the CNO signal with about 7σ C.L. The correspondent CNO neutrino flux is 6.6_{-0.9}^{+2.0}×10^{8} cm^{-2} s^{-1}, taking into account the neutrino flavor conversion. We use the new CNO measurement to evaluate the C and N abundances in the Sun with respect to the H abundance for the first time with solar neutrinos. Our result of N_{CN}=(5.78_{-1.00}^{+1.86})×10^{-4} displays a ∼2σ tension with the "low-metallicity" spectroscopic photospheric measurements. Furthermore, our result used together with the ^{7}Be and ^{8}B solar neutrino fluxes, also measured by Borexino, permits us to disfavor at 3.1σ C.L. the "low-metallicity" standard solar model B16-AGSS09met as an alternative to the "high-metallicity" standard solar model B16-GS98.

6.
Phys Rev Lett ; 121(11): 111303, 2018 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-30265123

RESUMEN

We present new constraints on sub-GeV dark-matter particles scattering off electrons based on 6780.0 kg d of data collected with the DarkSide-50 dual-phase argon time projection chamber. This analysis uses electroluminescence signals due to ionized electrons extracted from the liquid argon target. The detector has a very high trigger probability for these signals, allowing for an analysis threshold of three extracted electrons, or approximately 0.05 keVee. We calculate the expected recoil spectra for dark matter-electron scattering in argon and, under the assumption of momentum-independent scattering, improve upon existing limits from XENON10 for dark-matter particles with masses between 30 and 100 MeV/c^{2}.

7.
Phys Rev Lett ; 121(8): 081307, 2018 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-30192596

RESUMEN

We present the results of a search for dark matter weakly interacting massive particles (WIMPs) in the mass range below 20 GeV/c^{2} using a target of low-radioactivity argon with a 6786.0 kg d exposure. The data were obtained using the DarkSide-50 apparatus at Laboratori Nazionali del Gran Sasso. The analysis is based on the ionization signal, for which the DarkSide-50 time projection chamber is fully efficient at 0.1 keVee. The observed rate in the detector at 0.5 keVee is about 1.5 event/keVee/kg/d and is almost entirely accounted for by known background sources. We obtain a 90% C.L. exclusion limit above 1.8 GeV/c^{2} for the spin-independent cross section of dark matter WIMPs on nucleons, extending the exclusion region for dark matter below previous limits in the range 1.8-6 GeV/c^{2}.

8.
Phys Chem Chem Phys ; 20(15): 10292-10301, 2018 Apr 18.
Artículo en Inglés | MEDLINE | ID: mdl-29610793

RESUMEN

This study reports the structural and stoichiometric modifications of bismuth oxide nanoparticles in the ß phase (ß-Bi2O3) by UV pulsed laser irradiation in water or ethanol solutions. Scanning electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, UV-vis diffuse reflectance and high-resolution transmission electron microscopy were used to characterize the synthesized nanomaterials. The various analyses demonstrate that the laser irradiation of ß-Bi2O3 nanospheres is a green, fast and effective method to produce Bi2O2CO3 nanosheets or metallic Bi nanoparticles depending on the liquid environment used. Bi subcarbonate is obtained by laser irradiation in water, whereas metallic Bi is produced by laser irradiation in ethanol, and in particular the relative amount of metallic Bi is found to depend on the laser fluence. These typologies of materials find application in several fields, such as photocatalytic processes, light filters and environmental sensors.

9.
J Appl Microbiol ; 122(6): 1438-1455, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28160353

RESUMEN

Food safety is a critical public health issue for consumers and the food industry because microbiological contamination of food causes considerable social and economic burdens on health care. Most foodborne illness comes from animal production, but as of the mid-1990s in the United States and more recently in the European Union, the contribution of fresh produce to foodborne outbreaks has rapidly increased. Recent studies have suggested that sterilization with nonthermal plasma could be a viable alternative to the traditional methods for the decontamination of heat-sensitive materials or food because this technique proves capable of eliminating micro-organisms on surfaces without altering the substrate. In the last 10 years, researchers have used nonthermal plasma in a variety of food inoculated with many bacterial species. All of these experiments were conducted exclusively in a laboratory and, to our knowledge, this technique has not been used in an industrial setting. Thus, the purpose of this review is to understand whether this technology could be used at the industrial level. The latest researches using nonthermal plasma on fresh produce were analysed. These evaluations have focused on the log reduction of micro-organisms and the treatment time.


Asunto(s)
Descontaminación/métodos , Microbiología de Alimentos , Inocuidad de los Alimentos/métodos , Gases em Plasma , Animales , Contaminación de Alimentos/análisis , Contaminación de Alimentos/prevención & control , Industria de Procesamiento de Alimentos , Enfermedades Transmitidas por los Alimentos/epidemiología , Enfermedades Transmitidas por los Alimentos/microbiología , Enfermedades Transmitidas por los Alimentos/prevención & control , Salud Pública , Estados Unidos
10.
Phys Rev Lett ; 115(23): 231802, 2015 Dec 04.
Artículo en Inglés | MEDLINE | ID: mdl-26684111

RESUMEN

Borexino is a liquid scintillation detector located deep underground at the Laboratori Nazionali del Gran Sasso (LNGS, Italy). Thanks to the unmatched radio purity of the scintillator, and to the well understood detector response at low energy, a new limit on the stability of the electron for decay into a neutrino and a single monoenergetic photon was obtained. This new bound, τ≥6.6×10^{28} yr at 90% C.L., is 2 orders of magnitude better than the previous limit.

12.
Ann Ig ; 26(4): 367-79, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-25001126

RESUMEN

BACKGROUND: Evidence on pain management highlights the importance of a multidisciplinary approach in order to achieve optimal therapeutic results. Such programs can be guaranteed by the Centers for Pain Management (CPMs), in which multidisciplinary teams are able to provide advanced and specialized activities for the assessment, diagnosis and treatment of chronic benign pain. To date, information related to healthcare supply and the organizational structure of these centers in Italy is incomplete. The aim of this paper was to provide an overview of the healthcare network of the CPMs in the Lazio region. METHODS: A descriptive survey was conducted in all the 37 CPMs existing in the Lazio region in 2011 of which 28 participated. RESULTS: CPMs were located either in Universities or in public or private hospital facilities. They included a clinic, a Day Hospital service, Day surgery and day-beds. CPMs were managed by anaesthesiologists who, in most instances, did not work in a multidisciplinary team. The number of other health professionals available, such as nurses, psychologists and physiotherapists, was limited. CPMs mainly provided drug therapy, Complementary Alternative Medicine (CAM) and complex interventional treatments. The median waiting time was 30 days. The clinics were not homogeneously distributed in the region with a higher concentration in Rome (56%), followed by other provinces of the Lazio region (26%) and the province of Rome (18%). Clearly, Rome was the city which offered the greatest range of healthcare services and the highest number of consultations with patients, which significantly differed from those of the other areas (χ²=19.6 p<0.01). CONCLUSIONS: In 2011, the availability of CPMs was not equally distributed throughout the territory, and there was an over-utilization of the facilities in Rome and an under-utilization in the provincial areas. Moreover, this study showed a lack of a multi-professional approach to chronic pain management.


Asunto(s)
Clínicas de Dolor/organización & administración , Humanos , Italia
13.
J Environ Radioact ; 138: 444-6, 2014 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24725806

RESUMEN

The decays of (214)Po into (210)Pb and of (212)Po into (208)Pb tagged by the previous decays from (214)Bi and (212)Bi have been studied inserting quartz vials inside the Counting Test Facility (CTF) at the underground laboratory in Gran Sasso (LNGS). We find that the mean lifetime of (214)Po is (236.00 ± 0.42(stat) ± 0.15(syst)) µs and that of (212)Po is (425.1 ± 0.9(stat) ± 1.2(syst)) ns. Our results are compatible with previous measurements, have a much better signal to background ratio, and reduce the overall uncertainties.


Asunto(s)
Radioisótopos de Plomo/análisis , Polonio/análisis , Contaminantes Radiactivos/análisis , Partículas alfa , Semivida , Laboratorios , Monitoreo de Radiación
14.
J Appl Microbiol ; 116(5): 1137-48, 2014 May.
Artículo en Inglés | MEDLINE | ID: mdl-24443877

RESUMEN

AIM: The aim of this study was to investigate the effect of plasma-enhanced chemical vapour deposition (PECVD) treatment on selected bacteria and spores and to contribute to the understanding of the synergistic effect of UV-directed plasma. METHODS AND RESULTS: The experiments were conducted on pure cultures of Aspergillus brasiliensis and Escherichia coli and on naturally contaminated pistachios that were exposed to pure oxygen-, pure argon- and to a mixture of oxygen-argon-generated plasma for different treatment times and at different micro-organism concentrations. Optical emission spectroscopy (OES) measurements were performed to observe the active species in the plasma. After exposure, the effectiveness of decontamination was assessed through microbiological techniques by calculating the growth reduction on a logarithmic scale. A treatment time of 30 min resulted in a 3·5 log reduction of A. brasiliensis using pure oxygen or argon, while treatment times of 5 min, 1 min and 15 s resulted in a 5·4 log reduction using a mixture of argon and oxygen (10 : 1 v/v). Treatment times of 1 min and 30 s resulted in a 4 log reduction of E. coli with oxygen and argon, respectively, which led to a complete elimination of the micro-organisms. Two-log reductions of fungi were achieved for pistachios after a treatment time of 1 min. CONCLUSIONS: These results suggest that this newly designed plasma reactor offers good potential applications for the reduction in micro-organisms on heat-sensitive materials, such as foods. The plasma that was generated with Ar/O2 was more effective than that which was generated with pure oxygen and pure argon. SIGNIFICANCE AND IMPACT OF THE STUDY: An improvement in the knowledge about PECVD mechanisms was acquired from the chemical and biological points of view, and the suitability of the method for treating dry food surfaces was demonstrated.


Asunto(s)
Aspergillus/efectos de los fármacos , Escherichia coli/efectos de los fármacos , Pistacia/microbiología , Gases em Plasma/farmacología , Esterilización/métodos , Argón , Frío , Oxígeno/química , Gases em Plasma/química , Presión
15.
Plant Dis ; 98(10): 1387-1397, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-30703938

RESUMEN

Seven field experiments were conducted in Ohio and Illinois between 2011 and 2013 to evaluate postanthesis applications of prothioconazole + tebuconazole and metconazole for Fusarium head blight and deoxynivalenol (DON) control in soft red winter wheat. Treatments consisted of an untreated check and fungicide applications made at early anthesis (A), 2 (A+2), 4 (A+4), 5 (A+5), or 6 (A+6) days after anthesis. Six of the seven experiments were augmented with artificial Fusarium graminearum inoculum, and the other was naturally infected. FHB index (IND), Fusarium damaged kernels (FDK), and DON concentration of grain were quantified. All application timings led to significantly lower mean arcsine-square-root-transformed IND and FDK (arcIND and arcFDK) and log-transformed (logDON) than in the untreated check; however, arcIND, arcFDK, and logDON for the postanthesis applications were generally not significantly different from those for the anthesis applications. Relative to the check, A+2 resulted in the highest percent control for both IND and DON, 69 and 54%, respectively, followed by A+4 (62 and 52%), A+6 (62 and 48%), and A (56 and 50%). A+2 and A+6 significantly reduced IND by 30 and 14%, respectively, relative to the anthesis application. Postanthesis applications did not, however, reduce DON relative to the anthesis application. These results suggest that applications made up to 6 days following anthesis may be just as effective as, and sometimes more effective than, anthesis applications at reducing FHB and DON.

16.
Phys Rev Lett ; 108(5): 051302, 2012 Feb 03.
Artículo en Inglés | MEDLINE | ID: mdl-22400925

RESUMEN

We observed, for the first time, solar neutrinos in the 1.0-1.5 MeV energy range. We determined the rate of pep solar neutrino interactions in Borexino to be 3.1±0.6{stat}±0.3{syst} counts/(day·100 ton). Assuming the pep neutrino flux predicted by the standard solar model, we obtained a constraint on the CNO solar neutrino interaction rate of <7.9 counts/(day·100 ton) (95% C.L.). The absence of the solar neutrino signal is disfavored at 99.97% C.L., while the absence of the pep signal is disfavored at 98% C.L. The necessary sensitivity was achieved by adopting data analysis techniques for the rejection of cosmogenic {11}C, the dominant background in the 1-2 MeV region. Assuming the Mikheyev-Smirnov-Wolfenstein large mixing angle solution to solar neutrino oscillations, these values correspond to solar neutrino fluxes of (1.6±0.3)×10{8} cm{-2} s^{-1} and <7.7×10{8} cm{-2} s{-1} (95% C.L.), respectively, in agreement with both the high and low metallicity standard solar models. These results represent the first direct evidence of the pep neutrino signal and the strongest constraint of the CNO solar neutrino flux to date.

17.
Oncogene ; 31(34): 3857-65, 2012 Aug 23.
Artículo en Inglés | MEDLINE | ID: mdl-22139073

RESUMEN

Previous studies have demonstrated that high mobility group A proteins have a critical role on the onset of human pituitary adenomas. Indeed, both high mobility group A (HMGA) genes are overexpressed in pituitary adenomas, and consistently transgenic mice overexpressing either the Hmga1 or the Hmga2 gene develop mixed growth hormone/prolactin (GH-PRL)-secreting pituitary adenomas. Trisomy of chromosome 12, where HMGA2 is located, and/or amplification of the HMGA2 gene locus account for the HMGA2 overexpression in most human prolactinomas. Conversely, HMGA1 overexpression is not associated to any rearrangement or amplification of the HMGA1 locus. We have first identified micro RNAs (miRNAs) able to target both HMGA1 and HMGA2 messenger RNAs. Then, all of these miRNAs have been found downregulated in pituitary adenomas of different histotypes, compared with normal pituitary. Interestingly, their downregulation was also observed in nonfunctioning pituitary adenomas where HMGA2 overexpression is not associated to any alteration of the HMGA2 locus. Functional studies show that all these HMGA-targeting miRNAs inhibit the proliferation of the rat pituitary adenoma cell line GH3. Therefore, these results indicate that the downregulation of the miRNAs able to target the HMGA genes could contribute to increase HMGA protein levels in human pituitary adenomas, and then to pituitary tumorigenesis.


Asunto(s)
Transformación Celular Neoplásica/genética , Proteínas HMGA/genética , MicroARNs/genética , Neoplasias Hipofisarias/genética , Regiones no Traducidas 3'/genética , Animales , Secuencia de Bases , Sitios de Unión/genética , Western Blotting , Línea Celular , Línea Celular Tumoral , Transformación Celular Neoplásica/metabolismo , Transformación Celular Neoplásica/patología , Proteínas HMGA/metabolismo , Proteína HMGA1a/genética , Proteína HMGA1a/metabolismo , Proteína HMGA2/genética , Proteína HMGA2/metabolismo , Humanos , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Homología de Secuencia de Ácido Nucleico
18.
Phys Rev Lett ; 107(14): 141302, 2011 Sep 30.
Artículo en Inglés | MEDLINE | ID: mdl-22107184

RESUMEN

The rate of neutrino-electron elastic scattering interactions from 862 keV (7)Be solar neutrinos in Borexino is determined to be 46.0±1.5(stat)(-1.6)(+1.5)(syst) counts/(day·100 ton). This corresponds to a ν(e)-equivalent (7)Be solar neutrino flux of (3.10±0.15)×10(9) cm(-2) s(-1) and, under the assumption of ν(e) transition to other active neutrino flavours, yields an electron neutrino survival probability of 0.51±0.07 at 862 keV. The no flavor change hypothesis is ruled out at 5.0 σ. A global solar neutrino analysis with free fluxes determines Φ(pp)=6.06(-0.06)(+0.02)×10(10) cm(-2) s(-1) and Φ(CNO)<1.3×10(9) cm(-2) s(-1) (95% C.L.). These results significantly improve the precision with which the Mikheyev-Smirnov-Wolfenstein large mixing angle neutrino oscillation model is experimentally tested at low energy.

19.
Oncogene ; 30(27): 3024-35, 2011 Jul 07.
Artículo en Inglés | MEDLINE | ID: mdl-21339738

RESUMEN

DNA-damaging therapies represent a keystone in cancer treatment. Unfortunately, many tumors often relapse because of a group of cancer cells, which are resistant to conventional therapies. High-mobility group A (HMGA) proteins has a key role in cell transformation, and their overexpression is a common feature of human malignant neoplasias, representing a poor prognostic index often correlated to anti-cancer drug resistance. Our previous results demonstrated that HMGA1 is a substrate of ataxia-telangiectasia mutated (ATM), the main cellular sensor of genotoxic stress. Here we also report thatHMGA2, the other member of the HMGA family, is a novel substrate of ATM. Interestingly, we found that HMGA proteins positively regulate ATM gene expression. Moreover, induction of ATM kinase activity by DNA-damaging agents enhances HMGA-dependent transcriptional activation of ATM promoter, suggesting that ATM expression is modulated by a DNA-damage- and HMGA-dependent positive feedback loop. Finally, inhibition of HMGA expression in mouse embryonic fibroblasts and in cancer cells strongly reduces ATM protein levels, impairing the cellular DNA-damage response and enhancing the sensitivity to DNA-damaging agents. These findings indicate this novel HMGA-ATM pathway as a new potential target to improve the effectiveness of conventional anti-neoplastic treatments on the genotoxic-drug resistant cancer cells.


Asunto(s)
Proteínas de Ciclo Celular/genética , Proteínas de Unión al ADN/genética , Regulación Neoplásica de la Expresión Génica/fisiología , Proteínas HMGA/fisiología , Mutágenos/toxicidad , Proteínas Serina-Treonina Quinasas/genética , Proteínas Supresoras de Tumor/genética , Animales , Proteínas de la Ataxia Telangiectasia Mutada , Línea Celular , Humanos , Fosforilación , Regiones Promotoras Genéticas
20.
Phys Rev Lett ; 101(9): 091302, 2008 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-18851600

RESUMEN

We report the direct measurement of the 7Be solar neutrino signal rate performed with the Borexino detector at the Laboratori Nazionali del Gran Sasso. The interaction rate of the 0.862 MeV 7Be neutrinos is 49+/-3stat+/-4syst counts/(day.100 ton). The hypothesis of no oscillation for 7Be solar neutrinos is inconsistent with our measurement at the 4sigma C.L. Our result is the first direct measurement of the survival probability for solar nu(e) in the transition region between matter-enhanced and vacuum-driven oscillations. The measurement improves the experimental determination of the flux of 7Be, pp, and CNO solar nu(e), and the limit on the effective neutrino magnetic moment using solar neutrinos.

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