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1.
Phys Rev Lett ; 129(20): 201801, 2022 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-36461983

RESUMO

This Letter presents the results from the MiniBooNE experiment within a full "3+1" scenario where one sterile neutrino is introduced to the three-active-neutrino picture. In addition to electron-neutrino appearance at short baselines, this scenario also allows for disappearance of the muon-neutrino and electron-neutrino fluxes in the Booster Neutrino Beam, which is shared by the MicroBooNE experiment. We present the 3+1 fit to the MiniBooNE electron-(anti)neutrino and muon-(anti)neutrino data alone and in combination with MicroBooNE electron-neutrino data. The best-fit parameters of the combined fit with the exclusive charged-current quasielastic analysis (inclusive analysis) are Δm^{2}=0.209 eV^{2}(0.033 eV^{2}), |U_{e4}|^{2}=0.016(0.500), |U_{µ4}|^{2}=0.500(0.500), and sin^{2}(2θ_{µe})=0.0316(1.0). Comparing the no-oscillation scenario to the 3+1 model, the data prefer the 3+1 model with a Δχ^{2}/d.o.f.=24.7/3(17.3/3), a 4.3σ(3.4σ) preference assuming the asymptotic approximation given by Wilks's theorem.

2.
Morphologie ; 103(341 Pt 2): 94-102, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30905592

RESUMO

Polyhydroxyalkanoates (PHAs) are biomaterials widely investigated for tissue-engineering applications. In this regard, we describe a method to prepare fibers of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by a wet-spinning technique. Polymer fibers were used to test the cytocompatibility of the material in vitro. We have investigated their behavior in vitro in presence of the osteoblast-like (SaOs2) and macrophage (J774.2) cell lines. The PHBV fibers used were 100-200µm in diameter and offered a large surface for cell adhesion, similar to that they encounter when apposed onto a bone trabeculae. The fiber surface possessed a suitable roughness, a factor known to favor the adherence of cells, particularly osteoblasts. PHBV fibers were degraded in vitro by J774.2 cells as erosion pits were observable by transmission electron microscopy. The fibers were also colonisable by SaOs2 cells, which can spread and develop onto their surface. However, despite this good cytocompatibility observed in vitro, implantation in a bone defect drilled in rabbit femoral condyles showed that the material was only biotolerated without any sign of osteoconduction or degradation in vivo. We can conclude that PHBV is cytocompatible but is not suitable to be used as a bone graft as it does not favor osteoconduction and is not resorbed by bone marrow macrophages.


Assuntos
Materiais Biocompatíveis/administração & dosagem , Transplante Ósseo/métodos , Teste de Materiais , Poli-Hidroxialcanoatos/administração & dosagem , Alicerces Teciduais/química , Animais , Materiais Biocompatíveis/química , Regeneração Óssea/efeitos dos fármacos , Adesão Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fêmur/lesões , Fêmur/transplante , Humanos , Camundongos , Modelos Animais , Osteoblastos/efeitos dos fármacos , Poli-Hidroxialcanoatos/química , Coelhos
3.
Phys Rev Lett ; 121(22): 221801, 2018 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-30547637

RESUMO

The MiniBooNE experiment at Fermilab reports results from an analysis of ν_{e} appearance data from 12.84×10^{20} protons on target in neutrino mode, an increase of approximately a factor of 2 over previously reported results. A ν_{e} charged-current quasielastic event excess of 381.2±85.2 events (4.5σ) is observed in the energy range 200

4.
Phys Rev Lett ; 120(14): 141802, 2018 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-29694148

RESUMO

We report the first measurement of monoenergetic muon neutrino charged current interactions. MiniBooNE has isolated 236 MeV muon neutrino events originating from charged kaon decay at rest (K^{+}→µ^{+}ν_{µ}) at the NuMI beamline absorber. These signal ν_{µ}-carbon events are distinguished from primarily pion decay in flight ν_{µ} and ν[over ¯]_{µ} backgrounds produced at the target station and decay pipe using their arrival time and reconstructed muon energy. The significance of the signal observation is at the 3.9σ level. The muon kinetic energy, neutrino-nucleus energy transfer (ω=E_{ν}-E_{µ}), and total cross section for these events are extracted. This result is the first known-energy, weak-interaction-only probe of the nucleus to yield a measurement of ω using neutrinos, a quantity thus far only accessible through electron scattering.

5.
Phys Rev Lett ; 118(22): 221803, 2017 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-28621993

RESUMO

The MiniBooNE-DM Collaboration searched for vector-boson mediated production of dark matter using the Fermilab 8-GeV Booster proton beam in a dedicated run with 1.86×10^{20} protons delivered to a steel beam dump. The MiniBooNE detector, 490 m downstream, is sensitive to dark matter via elastic scattering with nucleons in the detector mineral oil. Analysis methods developed for previous MiniBooNE scattering results were employed, and several constraining data sets were simultaneously analyzed to minimize systematic errors from neutrino flux and interaction rates. No excess of events over background was observed, leading to a 90% confidence limit on the dark matter cross section parameter, Y=ε^{2}α_{D}(m_{χ}/m_{V})^{4}≲10^{-8}, for α_{D}=0.5 and for dark matter masses of 0.01

6.
ScientificWorldJournal ; 2014: 103462, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24600316

RESUMO

Gold-dendrimer nanocomposites were obtained for the first time by a simple colloidal approach based on the use of polyamidoamine dendrimers with succinamic acid terminal groups and dodecanediamine core. Spherical and highly crystalline nanoparticles with dimensions between 3 nm and 60 nm, and size-polydispersity depending on the synthesis conditions, have been generated. The influence of the stoichiometric ratio and the structural and architectural features of the dendrimers on the properties of the nanocomposites has been described. The self-assembling behaviour of these materials produces gold-dendrimer nanostructured porous networks with variable density, porosity, and composition. The investigations of the reaction systems, by TEM, at two postsynthesis moments, allowed to preliminary establish the control over the properties of the nanocomposite products. Furthermore, this study allowed better understanding of the mechanism of nanocomposite generation. Impressively, in the early stages of the synthesis, the organization of gold inside the dendrimer molecules has been evidenced by micrographs. Growth and ripening mechanisms further lead to nanoparticles with typical characteristics. The potential of such nanocomposite particles to induce calcification when coating a polymer substrate was also investigated.


Assuntos
Calcificação Fisiológica , Dendrímeros/química , Ouro/química , Nanocompostos/química , Dendrímeros/síntese química
7.
Phys Rev Lett ; 110(16): 161801, 2013 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-23679593

RESUMO

The MiniBooNE experiment at Fermilab reports results from an analysis of ν[over ¯](e) appearance data from 11.27×10(20) protons on target in the antineutrino mode, an increase of approximately a factor of 2 over the previously reported results. An event excess of 78.4±28.5 events (2.8σ) is observed in the energy range 200

8.
Phys Rev Lett ; 105(18): 181801, 2010 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-21231096

RESUMO

The MiniBooNE experiment at Fermilab reports results from a search for ¯ν_{µ}→¯ν_{e} oscillations, using a data sample corresponding to 5.66×10²° protons on target. An excess of 20.9±14.0 events is observed in the energy range 475

9.
Phys Rev Lett ; 103(11): 111801, 2009 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-19792365

RESUMO

The MiniBooNE Collaboration reports initial results from a search for nu(mu)-->nu(e) oscillations. A signal-blind analysis was performed using a data sample corresponding to 3.39x10(20) protons on target. The data are consistent with background prediction across the full range of neutrino energy reconstructed assuming quasielastic scattering, 200

10.
Rev Med Suisse ; 4(171): 1960-2, 1964-6, 1968-9, 2008 Sep 17.
Artigo em Francês | MEDLINE | ID: mdl-18847128

RESUMO

Mobile teams have been developed for the three ages to meet the needs of people who should receive--but do not access to--a psychiatric assessment or to specialized care. To achieve this goal, the teams built a strong partnership within the social network, both with relatives and professionals involved. The general principles of intervention are similar between the ages: a focused target population, assertive outreach which benefits also relatives and carers, multidisciplinary teams with a limited caseload to ensure availability. The specificities of each age will be analyzed.


Assuntos
Psiquiatria do Adolescente , Psiquiatria Geriátrica , Unidades Móveis de Saúde/estatística & dados numéricos , Psiquiatria/tendências , Adolescente , Adulto , Idoso , Criança , Psiquiatria Infantil , França , Humanos , Unidades Móveis de Saúde/tendências
11.
Rev Med Suisse ; 4(153): 957-8, 960, 962-3, 2008 Apr 16.
Artigo em Francês | MEDLINE | ID: mdl-18549083

RESUMO

idemiological studies reveal that aging has significant consequences in community mental health. The mobile Team of the old age psychiatry (EMPAA) in Lausanne has the mission to respond to the increasing demands of psychiatric care, in a flexible, rapid and economic way, combining a high level of conceptual specificity with the logic of proximity. This article describes the development of this mobile team and reports data on the demographic pattern of patients and degree of satisfaction in the caregiver network. The question that arises in this context is that of the extension of this model in the other geographical areas of the district (Vaud country).


Assuntos
Serviços de Saúde para Idosos , Transtornos Mentais/terapia , Serviços de Saúde Mental , Unidades Móveis de Saúde , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Suíça
12.
J Biomed Mater Res A ; 77(1): 35-42, 2006 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-16345096

RESUMO

Polymers are widely used in medicine for vascular prostheses, bone substitutes, and devices for controlled release. Among these polymers, poly(2-hydroxyethyl methacrylate) (pHEMA) is the most employed. To confer particular properties, pHEMA can be copolymerized with other monomers or in the presence of plasticizers or crosslinking agents. The influence of the length of crosslink chains on swelling, surface rugosity, hardness, and stiffness of crosslinked pHEMA were studied by several techniques, including fractal analysis and AFM. Four crosslinking agents (divinyl benzene, DVB; ethylene glycol dimethacrylate, EGDMA; tetraethylene glycol diacrylate, TEGDA; and polyethylene glycol diacrylate, PEGDA) were added to the bulk polymerization mixture. Only linear and PEGDA-pHEMA presented a significant decrease in surface roughness confirmed by fractal analysis. Differences in hardness and biomechanical properties were evidenced on dried polymers but the highest differences were exhibited for hydrated pHEMA. Correlations between the length of the crosslink chain and hardness or stiffness of hydrated crosslinked pHEMA were evidenced. TEGDA and PEGDA appeared to be the two most suitable crosslinking agents for controlled release of bioactive molecules in bone.


Assuntos
Resinas Compostas/química , Reagentes de Ligações Cruzadas/química , Poli-Hidroxietil Metacrilato/química , Materiais Biocompatíveis/química , Dureza , Estrutura Molecular , Estresse Mecânico , Propriedades de Superfície
13.
J Biomed Mater Res A ; 69(3): 584-9, 2004 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-15127406

RESUMO

Polymers can be interesting alternatives to bone grafts; they must present suitable mechanical and osteoconductive properties. Biomimetic properties may be a key factor for the recognition by bone cells. Methacryloyloxyethyl phosphate (MOEP) was found to enhance hydroxyapatite deposition. The copolymer containing MOEP and 1-vinyl-2-pyrrolidinone (50-50%) binds large amounts of calcium. Particles of the copolymer were used to fill large cranial bone defects in the rat. After a 12-week healing period, the animals were euthanized and the skulls examined by X-ray, histology, and electron microscopy (EM). The high phosphate content of the polymer conferred a marked calcium-binding capacity, and the particles were heavily calcified. They were embedded in a light fibrous stroma containing numerous capillaries and multinucleated giant cells. The osteoconductive properties were poor: only few trabeculae developed centripetally from the margins of the defects. There was no bone bonding and no osteoblast on the surface of the calcified material. Backscattered EM revealed that the degree of calcification was homogeneous in all particles. Calcium-phosphorus calcospherites were never observed. The material appeared to trap calcium but to impair nucleation because only small hydroxyapatite tablets were occasionally observed. Polyphosphated materials do not represent a suitable source of potentially usable bone substitutes.


Assuntos
Regeneração Óssea/fisiologia , Substitutos Ósseos/metabolismo , Metacrilatos/metabolismo , Fosfatos/metabolismo , Polímeros/metabolismo , Animais , Substitutos Ósseos/química , Humanos , Masculino , Metacrilatos/química , Estrutura Molecular , Fosfatos/química , Polímeros/química , Radiografia , Ratos , Ratos Wistar , Crânio/diagnóstico por imagem , Crânio/metabolismo , Crânio/patologia , Crânio/ultraestrutura
14.
Phys Rev Lett ; 92(9): 091801, 2004 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-15089459

RESUMO

We observe a net beam excess of 8.7+/-6.3(stat)+/-2.4(syst) events, above 160 MeV, resulting from the charged-current reaction of nu(micro) and/or nu;(mu) on C and H in the LSND detector. No beam-related muon background is expected in this energy regime. Within an analysis framework of pi(0)-->nu(mu)nu;(mu), we set a direct upper limit for this branching ratio of Gamma(pi(0)-->nu(mu)nu;(mu))/Gamma(pi(0)-->all)<1.6 x 10(-6) at 90% confidence level.

15.
Biomaterials ; 25(2): 205-13, 2004 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-14585708

RESUMO

Methacryloyloxyethyl phosphate is a methacrylic monomer used to modify different substrates by copolymerisation, in order to enhance hydroxyapatite deposition onto their surfaces. We report the synthesis of two copolymers series using increasing concentrations of methacryloyloxyethyl phosphate with (diethylamino) ethyl methacrylate and 1-vinyl-2-pyrrolidinone. Reactivity ratios were evaluated for the two copolymer systems. The influence of phosphate content and distribution on the capacity to form a calcium-rich layer was evaluated after immersion for 15 days in a synthetic body fluid. Corresponding homopolymers were synthesised as controls. Calcium-phosphorus globules were developed only on samples containing (diethylamino) ethyl methacrylate, and presenting a low density of phosphate groups. The amounts of calcium increased when higher concentrations of methacryloyloxyethyl phosphate were used. The use of 1-vinyl-2-pyrrolidinone was associated with greater calcium amounts, (compared to (diethylamino) ethyl methacrylate). The amine groups may favour the attraction of phosphorus, thus creating another way for the nucleation of calcium/phosphate crystals.


Assuntos
Cálcio/química , Metacrilatos/química , Polímeros/síntese química , Microscopia Eletrônica de Varredura , Análise Espectral
20.
Phys Rev D Part Fields ; 43(4): 1283-1299, 1991 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-10013498
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