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1.
Sci Data ; 8(1): 218, 2021 Aug 12.
Artigo em Inglês | MEDLINE | ID: mdl-34385471

RESUMO

The OPERA experiment was designed to discover the vτ appearance in a vµ beam, due to neutrino oscillations. The detector, located in the underground Gran Sasso Laboratory, consisted of a nuclear photographic emulsion/lead target with a mass of about 1.25 kt, complemented by electronic detectors. It was exposed from 2008 to 2012 to the CNGS beam: an almost pure vµ beam with a baseline of 730 km, collecting a total of 1.8·1020 protons on target. The OPERA Collaboration eventually assessed the discovery of vµâ†’vτ oscillations with a statistical significance of 6.1 σ by observing ten vτ CC interaction candidates. These events have been published on the Open Data Portal at CERN. This paper provides a detailed description of the vτ data sample to make it usable by the whole community.

2.
Radiat Environ Biophys ; 58(4): 575-583, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31463523

RESUMO

Phaseolus vulgaris L. plants were irradiated with different doses (0.3, 10, 50 and 100 Gy) of X-rays in order to obtain a reference curve of response to ionizing radiations for this species. Growth analysis, gas exchange and chlorophyll a fluorescence measurements were performed to estimate the radio-resistance of bean plants. Specifically, there was a negative influence of X-rays on the net photosynthesis rate at 50 and 100 Gy, already on the day of irradiation. Experimental data showed a recovery over time in the gas exchange while the theoretical maximum photochemical efficiency of the photosystem II (Fv/Fm) was fairly constant throughout the period of measurements (20 days) and for all the experimental conditions. On the other hand, the quantum yield of PSII linear electron transport (ΦPSII) and non-photochemical quenching (NPQ) were deeply influenced over time by X-ray dose, suggesting a decrease in the functionality of the photosynthetic apparatus at the highest radiation doses. The growth was affected only at the highest doses of radiation with a significant and severe reduction of leaf expansion and number of leaves per plant. Despite the arrest in growth, X-ray exposure seems to trigger an increased photochemical activity probably signifying that P. vulgaris plants have a fairly elevated resistance to this kind of ionizing radiation. Our current results will provide a complete analysis of the photosystem II (PSII) response of P. vulgaris to different doses (0.3, 10, 50 and 100 Gy) of X-rays, providing sound references for both space-oriented and radioecology questions.


Assuntos
Clorofila A/metabolismo , Phaseolus/efeitos da radiação , Fotossíntese/efeitos da radiação , Fluorescência , Phaseolus/fisiologia , Folhas de Planta , Radiação Ionizante , Radiografia , Raios X
3.
Phys Rev Lett ; 120(21): 211801, 2018 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-29883136

RESUMO

The OPERA experiment was designed to study ν_{µ}→ν_{τ} oscillations in the appearance mode in the CERN to Gran Sasso Neutrino beam (CNGS). In this Letter, we report the final analysis of the full data sample collected between 2008 and 2012, corresponding to 17.97×10^{19} protons on target. Selection criteria looser than in previous analyses have produced ten ν_{τ} candidate events, thus reducing the statistical uncertainty in the measurement of the oscillation parameters and of ν_{τ} properties. A multivariate approach for event identification has been applied to the candidate events and the discovery of ν_{τ} appearance is confirmed with an improved significance level of 6.1σ. |Δm_{32}^{2}| has been measured, in appearance mode, with an accuracy of 20%. The measurement of the ν_{τ} charged-current cross section, for the first time with a negligible contamination from ν[over ¯]_{τ}, and the first direct evidence for the ν_{τ} lepton number are also reported.

4.
Phys Rev Lett ; 115(12): 121802, 2015 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-26430986

RESUMO

The OPERA experiment was designed to search for ν_{µ}→ν_{τ} oscillations in appearance mode, i.e., by detecting the τ leptons produced in charged current ν_{τ} interactions. The experiment took data from 2008 to 2012 in the CERN Neutrinos to Gran Sasso beam. The observation of the ν_{µ}→ν_{τ} appearance, achieved with four candidate events in a subsample of the data, was previously reported. In this Letter, a fifth ν_{τ} candidate event, found in an enlarged data sample, is described. Together with a further reduction of the expected background, the candidate events detected so far allow us to assess the discovery of ν_{µ}→ν_{τ} oscillations in appearance mode with a significance larger than 5σ.

5.
G Ital Nefrol ; 30(2)2013.
Artigo em Italiano | MEDLINE | ID: mdl-23832463

RESUMO

BACKGROUND: Anaemia is a risk factor for death, adverse cardiovascular outcomes and poor quality of life in patients with chronic kidney disease (CKD). Erythropoietin Stimulating Agents (ESA) are the most used treatment option. In observational studies, higher haemoglobin (Hb) levels (around 11-13 g/dL) are associated with improved survival and quality of life compared to Hb levels around 9-10 g/dL. Randomized studies found that targeting higher Hb levels with ESA causes an increased risk of death, mainly due to adverse cardiovascular outcomes. It is possible that this is mediated by ESA dose rather than haemoglobin concentration, although this hypothesis has never been formally tested. METHODS: We present the protocol of the Clinical Evaluation of the Dose of Erythropoietins (C.E. DOSE) trial, which will assess the benefits and harms of a high versus a low ESA dose therapeutic strategy for the management of anaemia of end stage kidney disease (ESKD). This is a randomized, prospective open label blinded end-point (PROBE) design trial due to enroll 900 haemodialysis patients. Patients will be randomized 1:1 to 4000 UI/week i. v. versus 18000 UI/week i. v. of epoetin alfa, beta or any other epoetin in equivalent doses. The primary outcome of the trial is a composite of cardiovascular events. In addition, quality of life and costs of these two strategies will be assessed. The study has been approved and funded by the Italian Agency of Drugs (Agenzia Italiana del Farmaco (AIFA)) within the 2006 funding plan for independent research on drugs (registered at www.clinicaltrials.gov (NCT00827021)).


Assuntos
Anemia/tratamento farmacológico , Hematínicos/administração & dosagem , Diálise Renal , Anemia/economia , Anemia/etiologia , Nefropatias Diabéticas/complicações , Gerenciamento Clínico , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Hematínicos/efeitos adversos , Hematínicos/economia , Hematínicos/farmacologia , Hematínicos/uso terapêutico , Hemoglobinas/análise , Humanos , Falência Renal Crônica/sangue , Falência Renal Crônica/complicações , Falência Renal Crônica/terapia , Metanálise como Assunto , Pessoa de Meia-Idade , Estudos Observacionais como Assunto , Avaliação de Resultados em Cuidados de Saúde , Qualidade de Vida , Diálise Renal/efeitos adversos , Diálise Renal/economia , Projetos de Pesquisa , Risco
6.
Clin Oral Implants Res ; 24 Suppl A100: 122-6, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22220509

RESUMO

INTRODUCTION: Nowadays, aesthetic appearance is receiving more and more attention from clinicians and patients. Therefore, it is of paramount importance for the surgeon to maintain or to improve the quality and the stability of the soft tissue-implant interface. The scientific literature supports the idea that the immediate placement and provisionalization of endosseus implants and abutments can indeed offer additional clinical control over the peri-implant tissue architecture. On this basis, this prospective study aims to evaluate the changes in soft tissues around immediately loaded dental implants in full-arch rehabilitations, over a period of 3 months. MATERIALS AND METHODS: Fifteen subjects were treated for immediate full-arch rehabilitations. Following implant placement, provisional rehabilitations made of bisphenol-A-glycidyldimethacrylate (BIS-GMA) and resin were placed. All records were made using a periodontal probe. The facial soft-tissue level was measured evaluating the distance between the soft-tissue margin and the incisal edge of the crown. Moreover, papilla levels were measured at the mesial and distal sites from a reference line connecting the occlusal edge of the crowns. RESULTS: The average value at the mesial site was -0.035 mm (±1, median 0 mm), while at the midfacial site, it was 0 mm (±0.76, median 0 mm) and at the distal site, -0.05 mm (±0.92, median 0 mm). The plaque score index showed a reduction during the follow-up period. DISCUSSION: Our data indicate that no differences at the midfacial point were detectable over the observation period. This is in agreement with several studies; it is plausible that these results are linked to a correct position of the implant in the alveolar socket. Moreover, comparing our results with what has been reported by other authors, it is surprising that while other studies highlight that papilla loss at the mesial and distal aspect is an expected consequence of immediate implant restorations, our data do not show any changes. The explanation of these results remains unclear. Further studies are needed to support our data and to clarify what mechanisms are involved in the maintenance of soft tissue.


Assuntos
Implantes Dentários , Carga Imediata em Implante Dentário/métodos , Arcada Edêntula/reabilitação , Mucosa Bucal/cirurgia , Adulto , Bis-Fenol A-Glicidil Metacrilato , Retenção em Prótese Dentária , Estética Dentária , Feminino , Humanos , Masculino , Complicações Pós-Operatórias/epidemiologia , Estudos Prospectivos , Resultado do Tratamento , Cicatrização
7.
Biochim Biophys Acta ; 1797(5): 525-30, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20122896

RESUMO

Non-photochemical quenching (NPQ) is a complex and still unclear mechanism essential for higher plants. The intensive research on this subject has highlighted three main components of NPQ: energy-dependent process (qE); state transitions to balance the excitation of PSII and PSI (qT); and photoinhibitory processes (qI). Recently, these components have been resolved as quantum yields according to the energy partitioning approach that takes into account the rate constants of every process involved in the quenching mechanisms of excited chlorophylls. In this study a fully extended quantum yield approach and the introduction of novel equations to assess the yields of each NPQ component are presented. Furthermore, a complete analysis of the yield of NPQ in Beta vulgaris exposed to different irradiances has been carried out. In agreement with experimental results here it is shown that the previous approach may amplify the yield of qE component and flatten the quantitative results of fluorescence analysis. Moreover, the significance of taking into account the physiological variability of NPQ for a correct assessment of energy partitioning is demonstrated.


Assuntos
Beta vulgaris/química , Clorofila/química , Metabolismo Energético , Processos Fotoquímicos , Fluorescência , Fotossíntese , Complexo de Proteína do Fotossistema II/química , Termodinâmica
10.
Radiat Environ Biophys ; 31(1): 51-62, 1992.
Artigo em Inglês | MEDLINE | ID: mdl-1589574

RESUMO

The chlorophyll content and the fluorescence induction kinetics at two wavelengths (690 nm and 735 nm) have been measured in leaves of nine common broadleaf tree species during the autumnal chlorophyll breakdown. The ratio of the chlorophyll fluorescence maxima F690/F735 was determined at fluorescence maximum (fm) and at steady-state conditions (fs) by the laser-induced fluorescence emission using the two-wavelength fluorometer. The ratio F690/F735 increases with the leaf discolouring during the autumnal chlorophyll breakdown. The relationship between the chlorophyll content and the ratio F690/F735 can be expressed by a power function (curvilinear relationship) which is valid for all the species examined. In most cases the ratio F690/F735 measured in the upper leaf side is lower than that in the lower leaf side, but the trend is the same along the decreasing chlorophyll content. The ratio F690/F735 is always higher at maximum fluorescence than at steady-state fluorescence in the upper as well as lower leaf side and these values are well fitted in a linear correlation. This study confirms the usefulness of the ratio F690/F735 as a suitable non-destructive indicator of the in-vivo chlorophyll content, especially at medium and low chlorophyll content.


Assuntos
Clorofila/química , Estações do Ano , Árvores , Clorofila/metabolismo , Fluorescência , Cinética
11.
Photosynth Res ; 21(2): 117-22, 1989 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-24424530

RESUMO

We investigated several photosynthetic parameters of a virescent mutant of durum wheat and of its wild-type. Electron transport rate to ferricyanide was the same in the two genotypes when expressed on leaf area basis while O2 evolution of the leaf tissue in saturating light and CO2 was slightly higher in the yellow genotype. RuBPCase was also slightly higher. Quantum yield per absorbed light was similar in the two genotypes. P700 and Cyt f were less concentrated in the mutant while PS II was only marginally lower. The light response curve of CO2 assimilation indicated higher level of photosynthesis of the mutant in high light, which corresponded to a lower non-photochemical quenching compared to the wild-type. It is concluded that the reaction centres, cyt f and chlorophyll are not limiting factors of electron transport in wheat seedlings and that electron transport capacity is in excess with respect to that needed for driving photosynthesis. Since the differences in photosynthesis reflect differences in RuBPCase activity, it is suggested that this enzyme limits photosynthesis in wheat seedlings also at high light intensities.

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