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1.
Phys Rev Lett ; 130(5): 051802, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800478

RESUMO

The inclusive electron neutrino charged-current cross section is measured in the NOvA near detector using 8.02×10^{20} protons-on-target in the NuMI beam. The sample of GeV electron neutrino interactions is the largest analyzed to date and is limited by ≃17% systematic rather than the ≃7.4% statistical uncertainties. The double-differential cross section in final-state electron energy and angle is presented for the first time, together with the single-differential dependence on Q^{2} (squared four-momentum transfer) and energy, in the range 1 GeV≤E_{ν}<6 GeV. Detailed comparisons are made to the predictions of the GENIE, GiBUU, NEUT, and NuWro neutrino event generators. The data do not strongly favor a model over the others consistently across all three cross sections measured, though some models have especially good or poor agreement in the single differential cross section vs Q^{2}.

2.
Phys Rev Lett ; 127(20): 201801, 2021 Nov 12.
Artigo em Inglês | MEDLINE | ID: mdl-34860065

RESUMO

This Letter reports results from the first long-baseline search for sterile antineutrinos mixing in an accelerator-based antineutrino-dominated beam. The rate of neutral-current interactions in the two NOvA detectors, at distances of 1 and 810 km from the beam source, is analyzed using an exposure of 12.51×10^{20} protons-on-target from the NuMI beam at Fermilab running in antineutrino mode. A total of 121 of neutral-current candidates are observed at the far detector, compared to a prediction of 122±11(stat.)±15(syst.) assuming mixing only between three active flavors. No evidence for ν[over ¯]_{µ}→ν[over ¯]_{s} oscillation is observed. Interpreting this result within a 3+1 model, constraints are placed on the mixing angles θ_{24}<25° and θ_{34}<32° at the 90% C.L. for 0.05 eV^{2}≤Δm_{41}^{2}≤0.5 eV^{2}, the range of mass splittings that produces no significant oscillations at the near detector. These are the first 3+1 confidence limits set using long-baseline accelerator antineutrinos.

3.
Prog Urol ; 31(5): 275-281, 2021 Apr.
Artigo em Francês | MEDLINE | ID: mdl-33461866

RESUMO

PURPOSE: To compare the costs associated with GreenLight XPS 180W photoselective vaporization of the prostate (PVP) for an outpatient versus standard transurethral resection of the prostate (TURP) with a three nights hospitalization in a French private hospital. MATERIAL AND METHODS: A retrospective cost minimization analysis was performed between 2017 and 2019 in a French private hospital for the hospital stays associated with TURP and PVP procedures for benign prostatic hyperplasia (BPH). The peri-operative cost-benefit assessment of the two procedures was analyzed from the establishment's point of view according to the micro-costing method. RESULTS: 871 surgical treatment for BPH had been performed during the period of the study, including 743 photoselective laser vaporization (85%). The average length of stay of patients undergoing TURP was 3,7 days versus 0,9 days for PVP including 64,7% ambulatory. The cost-benefit was more of 500€ per patient in favor of ambulatory PVP compared with TURP in conventional three nights hospitalization for level 1 hospital stays. CONCLUSION: In this private hospital center, ambulatory PVP seemed more cost-effective than TURP with a three nights hospitalization for a severity level 1 patient. The financial profit for the establishment was mostly due to reduction of the main length of stay and ambulatory care. LEVEL OF EVIDENCE: 3.


Assuntos
Procedimentos Cirúrgicos Ambulatórios/economia , Custos e Análise de Custo , Hospitalização/economia , Terapia a Laser/economia , Prostatectomia/economia , Prostatectomia/métodos , Humanos , Masculino , Estudos Retrospectivos , Ressecção Transuretral da Próstata/economia
4.
J Appl Microbiol ; 129(1): 137-145, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32119179

RESUMO

AIMS: This study aimed to evaluate in vitro efficacy of essential oils (EOs) and their compounds (EOCs) alone or in combination against Aeromonas salmonicida subsp. salmonicida, the causative agent of furunculosis in salmonid fish. METHODS AND RESULTS: Antimicrobial activity of 13 EOs and 16 EOCs was investigated for four A. salmonicida subsp. salmonicida strains using broth microdilution. The checkerboard assay was used to evaluate a putative synergy between the most efficient EOs and EOCs against the tested strains. Cinnamon bark, oregano, clove, and thyme oils and their major compounds cinnamaldehyde, eugenol, carvacrol and thymol showed the lower minimum inhibitory concentration and minimum bactericidal concentration values. The association of cinnamaldehyde and eugenol (V/V: 30%/70%) showed a synergistic activity against three tested strains. The combinations of cinnamon with oregano, clove or thyme EOs showed a neutral or additive activity against all the tested strains. CONCLUSIONS: Cinnamon, oregano, clove and thyme oils and their major phytochemical compounds showed strong activities against A. salmonicida subsp. salmonicida strains. SIGNIFICANCE AND IMPACT OF THE STUDY: To reduce the use of antibiotics in aquaculture, phytochemicals such as cinnamaldehyde and eugenol can be tested alone or in combination in in vivo studies as functional feed alternatives.


Assuntos
Aeromonas salmonicida/efeitos dos fármacos , Antibacterianos/farmacologia , Óleos Voláteis/farmacologia , Compostos Fitoquímicos/farmacologia , Animais , Sinergismo Farmacológico , Furunculose/microbiologia , Testes de Sensibilidade Microbiana , Óleos Voláteis/química , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Salmonidae/microbiologia
5.
Opt Express ; 27(22): 31425-31434, 2019 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-31684377

RESUMO

We investigate the impact of the growth conditions of AlGaAsSb cladding layers on the properties of interband cascade lasers (ICLs). For an optimized structure emitting at 3.3 µm, we achieve an internal quantum efficiency of 65% per stage in good agreement with conventional ICL using InAs/AlSb superlattice cladding layers, in spite of internal losses of 15 cm-1 due to higher optical losses in the n-type AlGaAsSb alloys. Finally, we report a narrow ridge ICL emitting at 3.33 µm operating in continuous wave up to 80°C that produces 1 mW/uncoated facet at 80 °C, 10 mW at 40 °C and more than 12 mW at 20°C.

6.
Phys Rev Lett ; 123(15): 151803, 2019 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-31702305

RESUMO

The NOvA experiment has seen a 4.4σ signal of ν[over ¯]_{e} appearance in a 2 GeV ν[over ¯]_{µ} beam at a distance of 810 km. Using 12.33×10^{20} protons on target delivered to the Fermilab NuMI neutrino beamline, the experiment recorded 27 ν[over ¯]_{µ}→ν[over ¯]_{e} candidates with a background of 10.3 and 102 ν[over ¯]_{µ}→ν[over ¯]_{µ} candidates. This new antineutrino data are combined with neutrino data to measure the parameters |Δm_{32}^{2}|=2.48_{-0.06}^{+0.11}×10^{-3} eV^{2}/c^{4} and sin^{2}θ_{23} in the ranges from (0.53-0.60) and (0.45-0.48) in the normal neutrino mass hierarchy. The data exclude most values near δ_{CP}=π/2 for the inverted mass hierarchy by more than 3σ and favor the normal neutrino mass hierarchy by 1.9σ and θ_{23} values in the upper octant by 1.6σ.

7.
Phys Rev Lett ; 119(4): 041801, 2017 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-29341770

RESUMO

We report the results of a first experimental search for lepton number violation by four units in the neutrinoless quadruple-ß decay of ^{150}Nd using a total exposure of 0.19 kg yr recorded with the NEMO-3 detector at the Modane Underground Laboratory. We find no evidence of this decay and set lower limits on the half-life in the range T_{1/2}>(1.1-3.2)×10^{21} yr at the 90% C.L., depending on the model used for the kinematic distributions of the emitted electrons.

8.
Animal ; 18(3): 101081, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38335569

RESUMO

Cognitive enrichment is a promising but understudied type of environmental enrichment that aims to stimulate the cognitive abilities of animals by providing them with more opportunities to interact with (namely, to predict events than can occur) and to control their environment. In a previous study, we highlighted that farmed rainbow trout can predict daily feedings after two weeks of conditioning, the highest conditioned response being elicited by the combination of both temporal and signalled predictability. In the present study, we tested the feeding predictability that elicited the highest conditioned response in rainbow trout (both temporal and signalled by bubbles, BUBBLE + TIME treatment) as a cognitive enrichment strategy to improve their welfare. We thus analysed the long-term effects of this feeding predictability condition as compared with an unpredictable feeding condition (RANDOM treatment) on the welfare of rainbow trout, including the markers in the modulation of brain function, through a multidisciplinary approach. To reveal the brain regulatory pathways and networks involved in the long-term effects of feeding predictability, we measured gene markers of cerebral activity and plasticity, neurotransmitter pathways and physiological status of fish (oxidative stress, inflammatory status, cell type and stress status). After almost three months under these predictability conditions of feeding, we found clear evidence of improved welfare in fish from BUBBLE + TIME treatment. Feeding predictability allowed for a food anticipatory activity and resulted in fewer aggressive behaviours, burst of accelerations, and jumps before mealtime. BUBBLE + TIME fish were also less active between meals, which is in line with the observed decreased expression of transcripts related to the dopaminergic system. BUBBLE + TIME fish tented to present fewer eroded dorsal fin and infections to the pathogen Flavobacterium psychrophilum. Decreased expression of most of the studied mRNA involved in oxidative stress and immune responses confirm these tendencies else suggesting a strong role of feeding predictability on fish health status and that RANDOM fish may have undergone chronic stress. Fish emotional reactivity while isolated in a novel-tank as measured by fear behaviour and plasma cortisol levels were similar between the two treatments, as well as fish weight and size. To conclude, signalled combined with temporal predictability of feeding appears to be a promising approach of cognitive enrichment to protect brain function via the physiological status of farmed rainbow trout in the long term.


Assuntos
Oncorhynchus mykiss , Animais , Oncorhynchus mykiss/fisiologia , Cognição , Encéfalo
9.
Opt Express ; 20(16): 18138-44, 2012 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-23038361

RESUMO

We demonstrate rapid switching between picosecond and femtosecond operational regimes in a Cr(4+):forsterite laser, using an electrically-contacted GaInNAs SESAM with saturable absorption characteristics controlled via the quantum-confined Stark effect. Additionally, continuous picosecond pulse duration tuning by over a factor 3 is reported.

10.
Opt Express ; 19(10): 9995-10000, 2011 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-21643257

RESUMO

Efficient mode-locking in a Tm:KY(WO(4))(2) laser is demonstrated by using InGaAsSb quantum-well SESAMs. Self-starting ultrashort pulse generation was realized in the 1979-2074 nm spectral region. Maximum average output power up to 411 mW was produced around 1986 nm with the corresponding pulse duration and repetition rate of 549 fs and 105 MHz respectively. Optimised pulse durations of 386 fs were produced with an average power of 235 mW at 2029 nm.

11.
Opt Express ; 18(11): 11933-41, 2010 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-20589055

RESUMO

We report on cavity-dumping of a semiconductor disk laser as a method to generate energetic wavelength-tunable nanosecond pulses with repetition rates ranging from 0.1 to 4 MHz. Experimentally, emission of 24 ns pulses with peak output power of 41 W in a single beam output (and of 30 ns with peak power of 57 W in a combined beam output) with wavelength tuning from 1045 to 1080 nm was obtained. Numerical modeling is also introduced to provide more insight into the most important parameters controlling this mode of operation and to define optimization avenues.


Assuntos
Amplificadores Eletrônicos , Lasers Semicondutores , Nanotecnologia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
12.
Opt Express ; 18(21): 22090-8, 2010 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-20941110

RESUMO

We report on the spectroscopic characterization, continuous-wave and continuous wave mode-locked laser performance of bulk Tm(3+):GPNG fluorogermanate and Tm(3+)-Ho(3+):TZN tellurite glass lasers around 2 µm. A slope efficiency of up to 50% and 190 mW of output power were achieved from the Tm(3+):GPNG laser at 1944 nm during continuous wave operation. The Tm(3+)-Ho(3+):TZN laser produced a 26% slope efficiency with a maximum output power of 74 mW at 2012 nm. The Tm(3+):GPNG produced near-transform-limited pulses of 410 fs duration centered at 1997 nm with up to 84 mW of average output power and repetition frequency of 222 MHz when was passively modelocked using an ion-implanted InGaAsSb-based quantum well SESAM. Using the same SESAM, the Tm(3+)-Ho(3+):TZN laser generated 630-fs pulses with 38 mW of average output power at 2012 nm. Data analysis of pulses at different intracavity pulse energies provided an estimation of n(2) at 2012 nm of 2.9 × 10(-15) cm(2)/W for the Tm(3+)-Ho(3+):TZN.

13.
Opt Lett ; 35(18): 3027-9, 2010 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-20847767

RESUMO

We report, for the first time to our knowledge, femtosecond-pulse operation of a Tm,Ho:NaY(WO(4))(2) laser at around 2060 nm. Transform-limited 191 fs pulses are produced with an average output power of 82 mW at a 144 MHz pulse repetition frequency. Maximum output power of up to 155 mW is generated with a corresponding pulse duration of 258 fs. An ion-implanted InGaAsSb quantum-well-based semiconductor saturable absorber mirror is used for passive mode-locking maintenance.


Assuntos
Lasers de Estado Sólido , Fenômenos Ópticos , Análise Espectral , Fatores de Tempo
14.
Opt Lett ; 35(2): 172-4, 2010 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-20081958

RESUMO

We demonstrate, for the first time to our knowledge, femtosecond-regime mode locking of a Tm,Ho-codoped crystalline laser operating in the 2 microm spectral region. Transform-limited 570 fs pulses were generated at 2055 nm by a Tm,Ho:KY(WO(4))(2) laser that produced an average output power of 130 mW at a pulse repetition frequency of 118 MHz. Mode locking was achieved using an ion-implanted InGaAsSb quantum-well-based semiconductor saturable absorber mirror.

15.
AJNR Am J Neuroradiol ; 41(9): 1733-1739, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32816766

RESUMO

BACKGROUND AND PURPOSE: Focal areas of high signal intensity are T2WI/T2-FLAIR hyperintensities frequently found on MR imaging of children diagnosed with neurofibromatosis type 1, often thought to regress spontaneously during adolescence or puberty. Due to the risk of tumor in this population, some focal areas of high signal intensity may pose diagnostic problems. The objective of this study was to assess the characteristics and temporal evolution of focal areas of high signal intensity in children with neurofibromatosis type 1 using long-term follow-up with MR imaging. MATERIALS AND METHODS: We retrospectively examined the MRIs of children diagnosed with neurofibromatosis type 1 using the National Institutes of Health Consensus Criteria (1987), with imaging follow-up of at least 4 years. We recorded the number, size, and surface area of focal areas of high signal intensity according to their anatomic distribution on T2WI/T2-FLAIR sequences. A generalized mixed model was used to analyze the evolution of focal areas of high signal intensity according to age, and separate analyses were performed for girls and boys. RESULTS: Thirty-nine patients (ie, 285 MR images) with a median follow-up of 7 years were analyzed. Focal areas of high signal intensity were found in 100% of patients, preferentially in the infratentorial white matter (35% cerebellum, 30% brain stem) and in the capsular lenticular region (22%). They measured 15 mm in 95% of cases. They appeared from the age of 1 year; increased in number, size, and surface area to a peak at the age of 7; and then spontaneously regressed by 17 years of age, similarly in girls and boys. CONCLUSIONS: Focal areas of high signal intensity are mostly small (<15 mm) abnormalities in the posterior fossa or capsular lenticular region. Our results suggest that the evolution of focal areas of high signal intensity is not related to puberty with a peak at the age of 7 years. Knowledge of the predictive evolution of focal areas of high signal intensity is essential in the follow-up of children with neurofibromatosis type 1.


Assuntos
Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Neurofibromatose 1/diagnóstico por imagem , Neurofibromatose 1/patologia , Adolescente , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Interpretação de Imagem Assistida por Computador/métodos , Lactente , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Estudos Retrospectivos
16.
Opt Express ; 17(7): 5373-8, 2009 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-19333302

RESUMO

We report on the fast (approximately 50 micros) remote-controlled switching between continuous-wave (cw), cw mode-locked (ML) and Q-switched ML modes of operation of a Nd:YVO(4) laser using an optically-pumped saturable absorber (SA). Pulses as short as 40 ps with an average output power of 0.5 W are obtained in cw ML regime.


Assuntos
Lasers de Estado Sólido , Lasers , Neodímio , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
17.
Opt Express ; 17(26): 23536-43, 2009 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-20052061

RESUMO

A comparative study of thermal lensing effect in diode laser pumped Ng- and Np-cut Nd:KGd(WO4)2 (KGW) laser crystals was performed for laser emission polarized along the principle refractive axis, Nm. The thermal lens in the Ng-cut Nd: KGW was found to be weakly astigmatic with a positive refractive power for both the Nm- and Np-directions. For Np -cut Nd:KGW, strong astigmatism was observed and the refractive powers in the Ng- and Nm-directions had opposing signs. The degree of astigmatism was found to be considerably weaker for the Ng-cut Nd:KGW in comparison with the Np-cut one: 0.35 dptr/(W/cm2) and 2.85 dptr/(W/cm2), respectively. The ratio of the thermal lens refractive powers in the planes parallel and perpendicular to the laser emission polarisation were measured as +1.4 and -0.425 for Ng- and Np-cut Nd:KGW respectively.


Assuntos
Lasers de Estado Sólido , Lentes , Semicondutores , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Temperatura
18.
Opt Lett ; 34(17): 2587-9, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19724498

RESUMO

We report the first demonstration, to our knowledge, of passive mode locking in a Tm(3+), Ho(3+)-codoped KY(WO(4))(2) laser operating in the 2000-2060 nm spectral region. An InGaAsSb-based quantum well semiconductor saturable absorber mirror is used for the initiation and stabilization of the ultrashort pulse generation. Pulses as short as 3.3 ps were generated at 2057 nm with average output powers up to 315 mW at a pulse repetition frequency of 132 MHz for 1.15 W of absorbed pump power at 802 nm from a Ti:sapphire laser.


Assuntos
Hólmio/química , Lasers , Potássio/química , Túlio/química , Tungstênio/química , Ítrio/química , Adsorção , Óxido de Alumínio , Desenho de Equipamento , Luz , Óptica e Fotônica/métodos , Teoria Quântica , Semicondutores , Fatores de Tempo , Titânio/química
19.
Opt Express ; 16(23): 18739-44, 2008 Nov 10.
Artigo em Inglês | MEDLINE | ID: mdl-19581960

RESUMO

The operation of a femtosecond Cr(4+):YAG laser that incorporates a novel GaInNAsSb semiconductor saturable Bragg reflector is reported. In the mode-locked regime 230 fs pulses centred at 1528 nm were generated at an average output power of 280 mW. The SESAM exhibited a low saturation fluence of 10 microJ/cm(2) and a short recovery time of 12 ps.


Assuntos
Lasers de Estado Sólido , Nanotecnologia/instrumentação , Processamento de Sinais Assistido por Computador/instrumentação , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Folia Microbiol (Praha) ; 53(5): 417-22, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19085076

RESUMO

It was shown recently (Calvez et al. 2007) that glpQ and pde genes are involved in intermediate resistance of Enterococcus faecalis JH2-2 to DvnV41, a class IIa bacteriocin produced by Carnobacterium divergens V41. The listerial orthologs of lpQ and pde genes might be lmo0052 and lmo1292 genes, respectively. Here, the role of lmo0052 and lmo1292 genes in resistance of Listeria monocytogenes EGDe to DvnV41 and MesY105 was investigated. L. monocytogenes EGDe was inactivated in lmo0052 and/or lmo1292 by homologous recombination. Listerial mutant strain EGDSC02 (inactivated in the putative glpQ gene), was slightly resistant to DvnV41. The listerial mutant strain EGDSC01 (inactivated in the putative pde gene) remained, as the wild-type strain, sensitive to DvnV41, but was affected in growth parameters.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias , Bacteriocinas/farmacologia , Listeria monocytogenes/efeitos dos fármacos , Diester Fosfórico Hidrolases , Proteínas de Bactérias/efeitos dos fármacos , Proteínas de Bactérias/genética , Bacteriocinas/biossíntese , Farmacorresistência Bacteriana , Listeria monocytogenes/genética , Listeria monocytogenes/crescimento & desenvolvimento , Testes de Sensibilidade Microbiana , Mutação , Diester Fosfórico Hidrolases/efeitos dos fármacos , Diester Fosfórico Hidrolases/genética
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