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1.
J Nanosci Nanotechnol ; 21(4): 2312-2322, 2021 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-33500047

RESUMO

Looking for multifunctional materials, an assessment of the performances both as fire retardant and generator of electrically conductive surfaces for a three component mixture of graphene oxide, phosphoric acid and melamine applied on wood chipboard was performed. A simple approach was used to investigate the intumescent char formation and quantify the loss mass during vertical burning tests, in which the prepared samples were exposed for a certain time interval to a flame generated by an ethanol lamp in ambient conditions. Moreover, mass loss evolution and structural changes that occur during the burning process were more comprehensive investigated by differential thermal and thermogravimetric (DTA/TGA) techniques. By comparing the performances between the wood chipboard samples without any coverage and those covered with one or multiple component mixture, an increase of protection against the fire action was noticed when the three component mixture was used. Also, an improvement of the electrical properties was observed, after flame exposure of the samples covered with multiple layers (i.e., two and three), when the three component mixture was used. Morphological and structural investigations by microscopy (optical and electronic-SEMEDX), X-ray diffraction (XRD) and spectral (Raman, FTIR) methods are described. An assessment of market potential is also discussed.

2.
Phys Rev Lett ; 125(13): 131802, 2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-33034464

RESUMO

We report the final measurement of the neutrino oscillation parameters Δm_{32}^{2} and sin^{2}θ_{23} using all data from the MINOS and MINOS+ experiments. These data were collected using a total exposure of 23.76×10^{20} protons on target producing ν_{µ} and ν[over ¯]_{µ} beams and 60.75 kt yr exposure to atmospheric neutrinos. The measurement of the disappearance of ν_{µ} and the appearance of ν_{e} events between the Near and Far detectors yields |Δm_{32}^{2}|=2.40_{-0.09}^{+0.08}(2.45_{-0.08}^{+0.07})×10^{-3} eV^{2} and sin^{2}θ_{23}=0.43_{-0.04}^{+0.20}(0.42_{-0.03}^{+0.07}) at 68% C.L. for normal (inverted) hierarchy.

3.
Phys Rev Lett ; 125(7): 071801, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32857527

RESUMO

Searches for electron antineutrino, muon neutrino, and muon antineutrino disappearance driven by sterile neutrino mixing have been carried out by the Daya Bay and MINOS+ collaborations. This Letter presents the combined results of these searches, along with exclusion results from the Bugey-3 reactor experiment, framed in a minimally extended four-neutrino scenario. Significantly improved constraints on the θ_{µe} mixing angle are derived that constitute the most constraining limits to date over five orders of magnitude in the mass-squared splitting Δm_{41}^{2}, excluding the 90% C.L. sterile-neutrino parameter space allowed by the LSND and MiniBooNE observations at 90% CL_{s} for Δm_{41}^{2}<13 eV^{2}. Furthermore, the LSND and MiniBooNE 99% C.L. allowed regions are excluded at 99% CL_{s} for Δm_{41}^{2}<1.6 eV^{2}.

4.
Phys Rev Lett ; 122(9): 091803, 2019 Mar 08.
Artigo em Inglês | MEDLINE | ID: mdl-30932529

RESUMO

A search for mixing between active neutrinos and light sterile neutrinos has been performed by looking for muon neutrino disappearance in two detectors at baselines of 1.04 and 735 km, using a combined MINOS and MINOS+ exposure of 16.36×10^{20} protons on target. A simultaneous fit to the charged-current muon neutrino and neutral-current neutrino energy spectra in the two detectors yields no evidence for sterile neutrino mixing using a 3+1 model. The most stringent limit to date is set on the mixing parameter sin^{2}θ_{24} for most values of the sterile neutrino mass splitting Δm_{41}^{2}>10^{-4} eV^{2}.

5.
Phys Rev Lett ; 117(15): 151803, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768323

RESUMO

We report results of a search for oscillations involving a light sterile neutrino over distances of 1.04 and 735 km in a ν_{µ}-dominated beam with a peak energy of 3 GeV. The data, from an exposure of 10.56×10^{20} protons on target, are analyzed using a phenomenological model with one sterile neutrino. We constrain the mixing parameters θ_{24} and Δm_{41}^{2} and set limits on parameters of the four-dimensional Pontecorvo-Maki-Nakagawa-Sakata matrix, |U_{µ4}|^{2} and |U_{τ4}|^{2}, under the assumption that mixing between ν_{e} and ν_{s} is negligible (|U_{e4}|^{2}=0). No evidence for ν_{µ}→ν_{s} transitions is found and we set a world-leading limit on θ_{24} for values of Δm_{41}^{2}≲1 eV^{2}.

6.
Phys Rev Lett ; 117(15): 151801, 2016 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-27768356

RESUMO

Searches for a light sterile neutrino have been performed independently by the MINOS and the Daya Bay experiments using the muon (anti)neutrino and electron antineutrino disappearance channels, respectively. In this Letter, results from both experiments are combined with those from the Bugey-3 reactor neutrino experiment to constrain oscillations into light sterile neutrinos. The three experiments are sensitive to complementary regions of parameter space, enabling the combined analysis to probe regions allowed by the Liquid Scintillator Neutrino Detector (LSND) and MiniBooNE experiments in a minimally extended four-neutrino flavor framework. Stringent limits on sin^{2}2θ_{µe} are set over 6 orders of magnitude in the sterile mass-squared splitting Δm_{41}^{2}. The sterile-neutrino mixing phase space allowed by the LSND and MiniBooNE experiments is excluded for Δm_{41}^{2}<0.8 eV^{2} at 95% CL_{s}.

7.
Phys Rev Lett ; 116(15): 151806, 2016 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-27127961

RESUMO

We report results from the first search for ν_{µ}→ν_{e} transitions by the NOvA experiment. In an exposure equivalent to 2.74×10^{20} protons on target in the upgraded NuMI beam at Fermilab, we observe 6 events in the Far Detector, compared to a background expectation of 0.99±0.11(syst) events based on the Near Detector measurement. A secondary analysis observes 11 events with a background of 1.07±0.14(syst). The 3.3σ excess of events observed in the primary analysis disfavors 0.1π<δ_{CP}<0.5π in the inverted mass hierarchy at the 90% C.L.

8.
Phys Rev Lett ; 112(19): 191801, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-24877929

RESUMO

We report on a new analysis of neutrino oscillations in MINOS using the complete set of accelerator and atmospheric data. The analysis combines the ν(µ) disappearance and ν(e) appearance data using the three-flavor formalism. We measure |Δm(32)(2)| = [2.28-2.46] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.35-0.65 (90% C.L.) in the normal hierarchy, and |Δm(32)(2)| = [2.32-2.53] × 10(-3) eV(2) (68% C.L.) and sin(2)θ(23) = 0.34-0.67 (90% C.L.) in the inverted hierarchy. The data also constrain δ(CP), the θ(23} octant degeneracy and the mass hierarchy; we disfavor 36% (11%) of this three-parameter space at 68% (90%) C.L.

9.
Phys Rev Lett ; 110(25): 251801, 2013 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-23829728

RESUMO

We report measurements of oscillation parameters from ν(µ) and ν(µ) disappearance using beam and atmospheric data from MINOS. The data comprise exposures of 10.71×10(20) protons on target in the ν(µ)-dominated beam, 3.36×10(20) protons on target in the ν(µ)-enhanced beam, and 37.88 kton yr of atmospheric neutrinos. Assuming identical ν and ν oscillation parameters, we measure |Δm2| = (2.41(-0.10)(+0.09))×10(-3) eV2 and sin2(2θ) = 0.950(-0.036)(+0.035). Allowing independent ν and ν oscillations, we measure antineutrino parameters of |Δm2| = (2.50(-0.25)(+0.23))×10(-3) eV2 and sin2(2θ) = 0.97(-0.08)(+0.03), with minimal change to the neutrino parameters.

10.
Chirurgia (Bucur) ; 108(3): 341-5, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23790782

RESUMO

PURPOSE: To analyse the gastrostomy procedures performed in HNC patients admitted to Coltea Clinical Hospital in order to underline the similarities and differences to the data published worldwide. PATIENTS AND METHODS: Our retrospective study contains 64 HNC cases that met the inclusion criteria between 2008 and 2011. RESULTS AND DISCUSSIONS: The study group presents numerous specific characteristics (a larger number of cases aged over 55 than younger patients; elective use of classic gastrostomy instead of newer techniques; approximately two thirds of the gastrostomies were performed in patients with laryngeal carcinoma; only one third approximately of the cases benefited from prophylactic gastrostomy; etc.). CONCLUSIONS: 22% of the gastrostomies were made after the appearance of a pharyngocutaneous fistula. Therefore we will begin a future prospective study in order to ascertain the value of prophylactic PEG in preventing the appearance of pharyngocutaneous fistulas.


Assuntos
Carcinoma/terapia , Fístula Cutânea/prevenção & controle , Fístula do Sistema Digestório/prevenção & controle , Nutrição Enteral/métodos , Gastrostomia/métodos , Neoplasias de Cabeça e Pescoço/terapia , Doenças Faríngeas/prevenção & controle , Adulto , Idoso , Idoso de 80 Anos ou mais , Fístula Cutânea/etiologia , Fístula do Sistema Digestório/etiologia , Feminino , Humanos , Neoplasias Laríngeas/terapia , Masculino , Pessoa de Meia-Idade , Doenças Faríngeas/etiologia , Estudos Retrospectivos , Resultado do Tratamento
11.
Phys Rev Lett ; 110(17): 171801, 2013 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-23679706

RESUMO

We report on ν(e) and ν(e) appearance in ν(µ) and ν(µ) beams using the full MINOS data sample. The comparison of these ν(e) and ν(e) appearance data at a 735 km baseline with θ13 measurements by reactor experiments probes δ, the θ23 octant degeneracy, and the mass hierarchy. This analysis is the first use of this technique and includes the first accelerator long-baseline search for ν(µ) → ν(e). Our data disfavor 31% (5%) of the three-parameter space defined by δ, the octant of the θ23, and the mass hierarchy at the 68% (90%) C.L. We measure a value of 2sin(2)(2θ13)sin(2)(θ23) that is consistent with reactor experiments.

12.
Chirurgia (Bucur) ; 107(5): 640-5, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-23116839

RESUMO

PURPOSE: To analyze the risk factors associated with Nasopharyngeal Carcinoma (NPC)in patients admitted to the ENT Department at Coltea Clinical Hospital in order to assess the similarities and differences as compared to the epidemiological data internationally reported. PATIENTS AND METHODS: This is a retrospective study on 178 cases that met the inclusion criteria from 2003 to 2011. RESULTS AND DISCUSSIONS: There are a number of specific characteristics noticed in our study group: a larger number of cases aged over 60 than younger patients; a linear fall in number of the cases aged between 30-39 years; approximately one third of the cases did not have any of the traditional risk factors; more than 10% of the cases were associated with lymphoma, etc. CONCLUSIONS: The immunologic pattern of our patients presenting undifferentiated NPC is the following: MNF116, CK19, S100, CD34betaE12, Ki67, EBV positive. The rest of the markers were negative (CerB2, EGFR, COX2, p53, CK7, CD117, VGFR, PCNA, L26/CD20, UHCL1, CD15, CD30, VIM, TTF1, CLA, CK17, CEA, LMP, CD79a, EMA).


Assuntos
Biomarcadores Tumorais/análise , Carcinoma/diagnóstico , Carcinoma/imunologia , Neoplasias Nasofaríngeas/diagnóstico , Neoplasias Nasofaríngeas/imunologia , Adulto , Distribuição por Idade , Idoso , Idoso de 80 Anos ou mais , Alcoolismo/complicações , Anticorpos Antivirais/sangue , Antígenos CD34/análise , Carcinoma/epidemiologia , Carcinoma/radioterapia , Detecção Precoce de Câncer , Infecções por Vírus Epstein-Barr/complicações , Feminino , Substâncias Perigosas/efeitos adversos , Herpesvirus Humano 4/imunologia , Humanos , Queratina-19/análise , Queratinas/análise , Antígeno Ki-67/análise , Linfoma/complicações , Masculino , Pessoa de Meia-Idade , Neoplasias Nasofaríngeas/radioterapia , Valor Preditivo dos Testes , Prevalência , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Romênia/epidemiologia , Proteínas S100/análise , Sensibilidade e Especificidade , Distribuição por Sexo , Fumar/efeitos adversos
13.
Chirurgia (Bucur) ; 107(3): 373-8, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22844837

RESUMO

Basal cell Carcinoma (BCC) is the most common type of skin cancer, 85% of BCC are located in the head and neck area, of which 30% on the nose. The author present a retrospective study, own experience in surgical treatment in 31 cases with basal cell carcinoma of the nose operated in the period 2005-2011. The age of patients was between 50 to 90 years old. The anatomical site of the nose the most frecvently involved was ala 58%, and followed of the nasal tip 18%, lateral nose wall 12%, dorsum 9% and 3% basalioma terebrans. In all of the cases in this study it was performed the repair of the skin tumour defects of the nose, using varied local skin flaps, septal graft and auricle cartilage free grafts a ndcomposite (skin + cartilage) of conchal and helical rim. Treatment methods were depend on the tumor localization and extension. The best treatment option in BCC of the nose was radical surgical excision whith safety margin of the tumour, followed of reconstructive rhinoplasty.


Assuntos
Carcinoma Basocelular/cirurgia , Neoplasias Nasais/cirurgia , Rinoplastia/métodos , Retalhos Cirúrgicos , Idoso , Idoso de 80 Anos ou mais , Cartilagem/transplante , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Satisfação do Paciente , Estudos Retrospectivos , Resultado do Tratamento
14.
Artigo em Romano | MEDLINE | ID: mdl-2534836

RESUMO

On the basis of his experience in esophageal surgery (78 esophagoplasties--Gavriliu's techniques I and II) the author devised a semiflexible clip for making the new esophageal tube in the great gastric curvature. Unlike the other clips used, which sometimes produce lesions of the gastric mucosa or of the new esophageal tube--due to the rigidity of their arms--the new clip eliminates these shortcomings by two semiflexible arms (in the upper part) and an effort long scale (in the lower part).


Assuntos
Esofagoplastia/instrumentação , Estômago/transplante , Desenho de Equipamento , Humanos , Complicações Intraoperatórias/prevenção & controle
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