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1.
J Med Syst ; 47(1): 11, 2023 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-36645535

RESUMEN

To evaluate usability of and satisfaction with OrCam MyEye, a finger-size wearable assistive technology device for visually impaired during real-world tasks. This prospective multicenter study was conducted on visually impaired people recruited from 5 vision rehabilitation centers. Patients performed real-world tasks such as near and distance reading, money handling, colour identification and face recognition in 2 different scenarios: without using any low vision aid and with OrCam. System Usability Scale (SUS), Patient's Global Impression of Change (PGIC), the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0) and the Psychosocial Impact of Assistive Devices Scale (PIADS) were administered after the use of the OrCam device. Among the 100 participants, use of OrCam MyEye device improved many daily-living tasks (F = 1.67, P < .05), and in particular reading and face recognition. Multivariate logistic regression showed that age and visual field defect explained 89% of the variation in efficacy of the device. Nearly half (45%) of the participants indicated a positive rating with the SUS. The PGIC rates showed a minimal improvement with a mean score of 4.2 (SD:1.8). The most highlighted parameter with the QUEST 2.0 test was "ease of use" in 58% (48 subjects). The PIADS indicator showed that the device positively impacted on the daily-living tasks of users (r2 = 0.72, P < .05). Regression modelling demonstrated a good relation between the questionnaires scores and demographic, disease and visual factors (P < .05). OrCam MyEye allowed visually impaired people to read, handle money and face recognition independently. This device may offer to these subjects to be independent.


Asunto(s)
Equipos de Comunicación para Personas con Discapacidad , Dispositivos de Autoayuda , Personas con Daño Visual , Humanos , Satisfacción del Paciente , Estudios Prospectivos , Encuestas y Cuestionarios
2.
Nano Lett ; 21(14): 6064-6070, 2021 07 28.
Artículo en Inglés | MEDLINE | ID: mdl-34240608

RESUMEN

Numerous laboratories have observed random lasing from optically pumped solutions of plasmonic nanoparticles (NPs) suspended with organic dye molecules. The underlying mechanism is typically attributed to the formation of closed-loop optical cavities enabled by the large local field and scattering enhancements in the vicinity of plasmonic NPs. In this manuscript, we propose an alternative mechanism that does not directly require the plasmon resonance. We used high-speed confocal microspectroscopy to observe the photophysical dynamics of NPs in solution. Laser pulses induce the formation of microbubbles that surround and encapsulate the NPs, then sharp peaks <1.0 nm are observed that match the spectral signature of random lasing. Electromagnetic simulations indicate that ensembles of microbubbles may form optical corral containing standing wave patterns that are sufficient to sustain coherent optical feedback in a gain medium. Collectively, these results show that ensembles of plasmonic-induced bubbles can generate optical feedback and random lasing.


Asunto(s)
Microburbujas , Nanopartículas , Rayos Láser , Luz
3.
Opt Express ; 28(21): 31923-31931, 2020 Oct 12.
Artículo en Inglés | MEDLINE | ID: mdl-33115156

RESUMEN

We show how photoexcitation of a single plasmonic nanoparticle (NP) in solution can create a whispering-gallery-mode (WGM) droplet resonator. Small nano/microbubbles are initially formed by laser-induced heating that is localized by the plasmon resonance. Fast imaging shows that the bubbles collect and condense around the NP and form a droplet in the interior of the bubble. Droplets containing dye generated lasing modes with wavelengths that depend on the size of the droplet, refractive index of the solvent, and surrounding environment, matching the behavior of a WGM. We demonstrated this phenomenon with two kinds of Au NPs in addition to TiN NPs and observed cavity diameters as small as 4.8 µm with a free spectral range (FSR) of 12 nm. These results indicate that optical pumping of plasmonic NPs in a gain medium can generate lasing modes that are not directly associated with the plasmon cavity but can arise from its photophysical processes. This process may serve as a method to generate plasmonic/photonic optical microcavities in solution on demand at any location in a solvent using free-space coupling in/out of the cavity.

4.
Sci Rep ; 10(1): 13855, 2020 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-32807869

RESUMEN

We experimentally investigated the spectral dependence of the third-order susceptibility [Formula: see text] of Au triangular nanoplates in a broad wavelength region (400-1,000 nm). Complex shaped plasmonic nanoparticles provide a promising route to achieve control of their optical properties at the nanoscale. However, little is known about the effects of geometrical parameters to the optical nonlinearities and underlying mechanisms of the plasmon modes. Here, we obtained the [Formula: see text] of Au triangular nanoplates featuring a narrow plasmon resonance that is tunable in the visible and near-IR regions. This work demonstrates that the plasmonic triangular nanoplates simultaneously shows self-focusing and -defocusing, and saturable and reverse-saturable absorption properties at specific wavelength regions. Maximum amplitudes of real and imaginary components are - 6.8 × 10-18 m2/V2 at 668 nm and - 6.7 × 10-18 m2/V2 at 646 nm, respectively. Spectral dependence of the quantity [Formula: see text] enables comparison between different shaped plasmonic NPs to boost active plasmonic applications performance.

5.
Opt Express ; 27(14): 19168-19176, 2019 Jul 08.
Artículo en Inglés | MEDLINE | ID: mdl-31503680

RESUMEN

We experimentally determined the dispersion of the complex third-order nonlinear optical susceptibility χ(3) of Au nanorods over a wide bandwidth (370 - 800 nm). Compared to bulk Au, these nanorods exhibit greatly enhanced nonlinearities that can be manipulated by geometrical parameters. Accurately measuring the χ(3) values of nanostructured metals is challenging because χ(3) is strongly influenced by the local field effects. Hence the current published χ(3) values for Au nanorods have huge variations in both magnitude and sign because Z-scan measurements are used almost exclusively. This work combines pump-probe methods with spectroscopic ellipsometry to show that Au nanorods exhibit strong wavelength dependence and enhanced χ(3) in the vicinity of the longitudinal plasmon mode and explains where the regions of SA and RSA exist and how focusing and defocusing affects χ(3). In this context, the results highlight the importance of the dispersion of the quantity χ(3) to design plasmonic platforms for nanophotonics applications.

6.
Rev. bras. psiquiatr ; 40(3): 244-248, July-Sept. 2018. tab
Artículo en Inglés | LILACS | ID: biblio-959236

RESUMEN

Objective: To compare social skills and related executive functions among bipolar disorder (BD) patients with a family history of mood disorders (FHMD), BD patients with no FHMD and healthy control (HCs). Methods: We evaluated 20 euthymic patients with FHMD, 17 euthymic patients without FHMD, and 31 HCs using the Social Skills Inventory (SSI) and a neuropsychological battery evaluating executive function, inhibitory control, verbal fluency and estimated intelligence. Results: Both BD groups had lower SSI scores than controls. Scores for one subfactor of the social skills questionnaire, conversational skills and social performance, were significantly lower among patients with FHMD than among patients without FHMD (p = 0.019). Both groups of BD patients exhibited significant deficits in initiation/inhibition, but only BD patients with FHMD had deficits in verbal fluency, both compared to HC. There were no associations between social skills questionnaire scores and measures of cognitive function. Conclusion: Euthymic BD patients have lower social skills and executive function performance than HC. The presence of FHMD among BD patients is specifically associated with deficits in conversational and social performance skills, in addition to deficits in verbal fluency. Both characteristics might be associated with a common genetically determined pathophysiological substrate.


Asunto(s)
Humanos , Masculino , Femenino , Adolescente , Adulto , Persona de Mediana Edad , Adulto Joven , Trastorno Bipolar/psicología , Cognición , Trastornos del Conocimiento/psicología , Trastornos del Humor/psicología , Función Ejecutiva , Habilidades Sociales , Conducta Verbal/fisiología , Trastorno Bipolar/genética , Inducción de Remisión , Estudios de Casos y Controles , Trastornos del Conocimiento/genética , Inteligencia , Pruebas Neuropsicológicas
7.
Braz J Psychiatry ; 40(3): 244-248, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29590265

RESUMEN

OBJECTIVE: To compare social skills and related executive functions among bipolar disorder (BD) patients with a family history of mood disorders (FHMD), BD patients with no FHMD and healthy control (HCs). METHODS: We evaluated 20 euthymic patients with FHMD, 17 euthymic patients without FHMD, and 31 HCs using the Social Skills Inventory (SSI) and a neuropsychological battery evaluating executive function, inhibitory control, verbal fluency and estimated intelligence. RESULTS: Both BD groups had lower SSI scores than controls. Scores for one subfactor of the social skills questionnaire, conversational skills and social performance, were significantly lower among patients with FHMD than among patients without FHMD (p = 0.019). Both groups of BD patients exhibited significant deficits in initiation/inhibition, but only BD patients with FHMD had deficits in verbal fluency, both compared to HC. There were no associations between social skills questionnaire scores and measures of cognitive function. CONCLUSION: Euthymic BD patients have lower social skills and executive function performance than HC. The presence of FHMD among BD patients is specifically associated with deficits in conversational and social performance skills, in addition to deficits in verbal fluency. Both characteristics might be associated with a common genetically determined pathophysiological substrate.


Asunto(s)
Trastorno Bipolar/psicología , Trastornos del Conocimiento/psicología , Cognición , Función Ejecutiva , Trastornos del Humor/psicología , Habilidades Sociales , Adolescente , Adulto , Trastorno Bipolar/genética , Estudios de Casos y Controles , Trastornos del Conocimiento/genética , Femenino , Humanos , Inteligencia , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Inducción de Remisión , Conducta Verbal/fisiología , Adulto Joven
8.
Implant Dent ; 26(3): 345-350, 2017 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-28362688

RESUMEN

PURPOSE: To evaluate survival rate and bone response around immediate loaded Morse taper implants installed in fresh sockets on the anterior area of the maxilla. MATERIAL AND METHODS: The sample comprised 16 patients in whom 16 single implants were installed. All the teeth were extracted in a flapless surgery. Radiographic and tomographic evaluations were performed immediately after surgery (T1) and after 12 months (T2). The variables studied were height of the buccal wall (HBW), buccal wall width (BW) at 3 levels, and proximal bone height at 2 different areas: the alveolar crest level (CLH) and at the point where bone tissue meets the implant surface (BIS). RESULTS: Statistically significant differences were observed. The buccal plate showed bone loss in height (HBW = -0.50 ± 0.42 mm) and in width (BW-1 = -0.71 ± 0.48 mm; BW-2 = -0.48 ± 0.34 mm; BW-3 = -0.48 ± 0.34 mm). In the proximal areas, there was also bone loss in height (CLH-M = -0.85 ± 0.89 mm; BIS-M = -0.91 ± 0.70 mm; CLH-D = -0.64 ± 0.57 mm; and BIS-D = -0.68 ± 0.62 mm). CONCLUSION: There was 100% survival rate after a 12-month period, but bone loss was observed in all evaluated areas.


Asunto(s)
Pérdida de Hueso Alveolar/diagnóstico por imagen , Implantes Dentales de Diente Único , Carga Inmediata del Implante Dental/métodos , Adulto , Proceso Alveolar/diagnóstico por imagen , Proceso Alveolar/cirugía , Coronas , Diseño de Prótesis Dental , Femenino , Humanos , Masculino , Maxilar/cirugía , Persona de Mediana Edad , Osteotomía , Estudios Prospectivos , Alveolo Dental/cirugía , Resultado del Tratamiento
9.
J Affect Disord ; 161: 104-8, 2014 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-24751316

RESUMEN

OBJECTIVES: To compare clinical characteristics of bipolar disorder (BD) in patients with and without a family history of mood disorders (FHMD) in a large sample from the Brazilian Research Network of Bipolar Disorders. METHODS: Four-hundred eighty-eight DSM-IV BD patients participating in the Brazilian Research Network of Bipolar Disorders were included. Participants were divided between those with FHMD (n=230) and without FHMD (n=258). We compared these two groups on demographic and clinical variables and performed a logistic regression to identify which variables were most strongly associated with positive family history of mood disorders. RESULTS: BD patients with FHMD presented with significantly higher lifetime prevalence of any anxiety disorder, obsessive-compulsive disorder, social phobia, substance abuse, and were more likely to present history of suicide attempts, family history of suicide attempts and suicide, and more psychiatric hospitalizations than BD patients without FHMD. Logistic regression showed that the variables most strongly associated with a positive FHMD were any comorbid anxiety disorder, comorbid substance abuse, and family history of suicide. LIMITATIONS: Cross-sectional study and verification of FHMD by indirect information. CONCLUSION: BD patients with FHMD differ from BD patients without FHMD in rates of comorbid anxiety disorder and substance abuse, number of hospitalizations and suicide attempts. As FHMD is routinely assessed in clinical practice, these findings may help to identify patients at risk for particular manifestations of BD and may point to a common, genetically determined neurobiological substrate that increases the risk of conditions such as comorbidities and suicidality in BD patients.


Asunto(s)
Trastornos de Ansiedad/psicología , Trastorno Bipolar/psicología , Trastornos Relacionados con Sustancias/psicología , Adolescente , Adulto , Trastornos de Ansiedad/epidemiología , Trastornos de Ansiedad/genética , Trastorno Bipolar/epidemiología , Trastorno Bipolar/genética , Brasil , Estudios de Casos y Controles , Comorbilidad , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Prevalencia , Riesgo , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/genética , Suicidio , Intento de Suicidio/psicología
10.
Inhal Toxicol ; 24(5): 288-95, 2012 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-22486346

RESUMEN

The study presented here is a laboratory pilot study using diluted car exhaust from a single vehicle to assess differences in toxicological response between primary emissions and secondary products resulting from atmospheric photochemical reactions of gas phase compounds with O3, OH and other radicals. Sprague Dawley rats were exposed for 5 h to either filtered room air (sham) or one of two different atmospheres: (i) diluted car exhaust (P)+Mt. Saint Helens Ash (MSHA); (ii) P+MSHA+secondary organic aerosol (SOA, formed during simulated photochemical aging of diluted exhaust). Primary and secondary gases were removed using a nonselective diffusion denuder. Continuous respiratory data was collected during the exposure, and bronchoalveolar lavage (BAL) and complete blood counts (CBC) were performed 24 h after exposure. ANOVA models were used to assess the exposure effect and to compare those effects across different exposure types. Total average exposures were 363 ± 66 µg/m³ P+MSHA and 212 ± 95 µg/m³ P+MSHA+SOA. For both exposures, we observed decreases in breathing rate, tidal and minute volumes (TV, MV) and peak and median flows (PIF, PEF and EF50) along with increases in breathing cycle times (Ti, Te) compared to sham. These results indicate that the animals are changing their breathing pattern with these test atmospheres. Exposure to P+MSHA+SOA produced significant increases in total cells, macrophages and neutrophils in the BAL and in vivo chemiluminescence of the lung. There were no significant differences in CBC parameters. Our data suggest that simulated atmospheric photochemistry, producing SOA in the P+MSHA+SOA exposures, enhanced the toxicity of vehicular emissions.


Asunto(s)
Contaminantes Atmosféricos/toxicidad , Material Particulado/toxicidad , Respiración/efectos de los fármacos , Emisiones de Vehículos/toxicidad , Compuestos Orgánicos Volátiles/toxicidad , Animales , Recuento de Células Sanguíneas , Líquido del Lavado Bronquioalveolar/química , Líquido del Lavado Bronquioalveolar/citología , Masculino , Proyectos Piloto , Ratas , Ratas Sprague-Dawley
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