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1.
Pilot Feasibility Stud ; 9(1): 36, 2023 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-36895054

RESUMO

BACKGROUND: The social determinants of health (SDOH) are the conditions in which people are born, grow, work, live, and age. Lack of SDOH training of dental providers on SDOH may result in suboptimal care provided to pediatric dental patients and their families. The purpose of this pilot study is to report the feasibility and acceptability of SDOH screening and referral by pediatric dentistry residents and faculty in the dental clinics of Family Health Centers at NYU Langone (FHC), a Federally Qualified Health Center (FQHC) network in Brooklyn, NY, USA. METHODS: Guided by the Implementation Outcomes Framework, 15 pediatric dentists and 40 pediatric dental patient-parent/guardian dyads who visited FHC in 2020-2021 for recall or treatment appointments participated in this study. The a priori feasibility and acceptability criteria for these outcomes were that after completing the Parent Adversity Scale (a validated SDOH screening tool), ≥ 80% of the participating parents/guardians would feel comfortable completing SDOH screening and referral at the dental clinic (acceptable), and ≥ 80% of the participating parents/guardians who endorsed SDOH needs would be successfully referred to an assigned counselor at the Family Support Center (feasible). RESULTS: The most prevalent SDOH needs endorsed were worried within the past year that food would run out before had money to buy more (45.0%) and would like classes to learn English, read better, or obtain a high school degree (45.0%). Post-intervention, 83.9% of the participating parents/guardians who expressed an SDOH need were successfully referred to an assigned counselor at the Family Support Center for follow-up, and 95.0% of the participating parents/guardians felt comfortable completing the questionnaire at the dental clinic, surpassing the a priori feasibility and acceptability criteria, respectively. Furthermore, while most (80.0%) of the participating dental providers reported being trained in SDOH, only one-third (33.3%) usually or always assess SDOH for their pediatric dental patients, and most (53.8%) felt minimally comfortable discussing challenges faced by pediatric dental patient families and referring patients to resources in the community. CONCLUSIONS: This study provides novel evidence of the feasibility and acceptability of SDOH screening and referral by dentists in the pediatric dental clinics of an FQHC network.

2.
Opt Lett ; 42(23): 4857-4860, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29216128

RESUMO

Spectral and coherence evolutions were measured for supercontinuum (SC) generated in a 2.7 cm highly nonlinear tellurite photonic crystal fiber. Numerical simulations were performed based on the generalized nonlinear Schrödinger equation with noise. The measurements show that coherence degradation first occurs after soliton fission, and then spreads to longer wavelengths as the average power of the SC increases. The solitonic coherence shows much slower degradation than the overall coherence.

3.
Pediatr Dent ; 39(2): 94-95, 2017 03 15.
Artigo em Inglês | MEDLINE | ID: mdl-28390454
4.
Opt Express ; 21(6): 6783-93, 2013 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-23546061

RESUMO

A new diffractive imaging technique called Imaging By Integrating Stitched Spectrograms (IBISS) is presented. Both the data collection and phase retrieval algorithm used in IBISS are direct extensions of frequency resolved optical gating to higher dimensions. Data collection involves capturing an array of diffraction patterns generated by scanning a sample across a coherent beam of light. Phase retrieval is performed using the Principal Components Generalized Projections Algorithm (PCGPA) by reducing the four dimensional data set of images to two remapped two-dimensional sets. The technique is successfully demonstrated using a Helium Neon laser to image a 350µm wide sample with 12µm resolution.


Assuntos
Algoritmos , Interpretação de Imagem Assistida por Computador/instrumentação , Interpretação de Imagem Assistida por Computador/métodos , Refratometria/instrumentação , Refratometria/métodos , Análise Espectral/instrumentação , Análise Espectral/métodos , Desenho de Equipamento , Análise de Falha de Equipamento , Integração de Sistemas
5.
Opt Express ; 21(7): 8007-17, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23571891

RESUMO

Current pulse measurement methods have proven inadequate to fully understand the characteristics of passively mode-locked quantum-dot diode lasers. These devices are very difficult to characterize because of their low peak powers, high bandwidth, large time-bandwidth product, and large timing jitter. In this paper, we discuss the origin for the inadequacies of current pulse measurement techniques while presenting new ways of examining frequency-resolved optical gating (FROG) data to provide insight into the operation of these devices. Under the assumptions of a partial coherence model for the pulsed laser, it is shown that simultaneous time-frequency characterization is a necessary and sufficient condition for characterization of mode-locking. Full pulse characterization of quantum dot passively mode-locked lasers (QD MLLs) was done using FROG in a collinear configuration using an aperiodically poled lithium niobate waveguide-based FROG pulse measurement system.


Assuntos
Lasers Semicondutores , Modelos Teóricos , Pontos Quânticos , Simulação por Computador , Desenho Assistido por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
6.
Opt Lett ; 34(17): 2602; discussion 2603, 2009 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-19724503

RESUMO

The authors of an earlier paper [Opt. Lett. 32, 3558 (2007)] reported two "ambiguities" in second-harmonic-generation frequency-resolved optical gating (FROG). One ambiguity is simply wrong--a miscalculation. The other is well known and easily avoided in simple well-known FROG variations. Finally, the authors' main conclusion--that autocorrelation can be more sensitive to pulse variations than FROG--is also wrong.

7.
Appl Opt ; 46(18): 3870-7, 2007 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-17538685

RESUMO

Complex-conjugate-resolved Fourier-domain optical coherence tomography, where the quadrature components of the interferogram are obtained by simultaneous acquisition of the first and second harmonics of the phase-modulated interferogram, is applied to multisurface test targets and biological samples. The method provides efficient suppression of the complex-conjugate, dc, and autocorrelation artifacts. A complex-conjugate rejection ratio as high as 70 dB is achieved.


Assuntos
Óptica e Fotônica , Animais , Análise de Fourier , Interferometria , Microscopia/métodos , Modelos Estatísticos , Projetos de Pesquisa , Sensibilidade e Especificidade , Espectrofotometria , Fatores de Tempo , Xenopus laevis
8.
Opt Lett ; 31(9): 1271-3, 2006 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-16642082

RESUMO

A method of resolving the complex conjugate ambiguity in Fourier-domain OCT is described. The complex differential spectral interferogram is obtained by simultaneous acquisition of the first and second harmonics of the ac component of the phase-modulated interferogram. The harmonics represent the imaginary and real parts of the interferogram, respectively. The complex conjugate rejection ratio is found to be at least 45 dB and is limited by background noise.


Assuntos
Algoritmos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Análise Espectral/métodos , Tomografia de Coerência Óptica/métodos , Análise de Fourier , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
9.
Appl Opt ; 42(34): 6953-8, 2003 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-14661810

RESUMO

A Michelson-type spectral interferometer that uses a common beam path for the reference and the sample arms is described. This optical arrangement is more compact and stable than the more commonly used dual-arm interferometer and is well suited for frequency-domain optical coherence tomography of biological samples. With a 16-bit CCD camera, the instrument has sufficient dynamic range and resolution for imaging to depths of 2 mm in scattering biological materials. Images obtained with this spectral interferometer are presented, including cross-sectional images in a Xenopus laevis tadpole.


Assuntos
Abdome/anatomia & histologia , Interpretação de Imagem Assistida por Computador/métodos , Microscopia de Interferência/instrumentação , Microscopia de Interferência/métodos , Tomografia de Coerência Óptica/instrumentação , Tomografia de Coerência Óptica/métodos , Gravação em Vídeo/instrumentação , Algoritmos , Animais , Desenho de Equipamento , Análise de Falha de Equipamento , Estudos de Viabilidade , Análise de Fourier , Larva , Espalhamento de Radiação , Gravação em Vídeo/métodos , Xenopus laevis
10.
Opt Lett ; 28(15): 1332-4, 2003 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-12906080

RESUMO

Differential spectral interferometry (DSI), a novel method of biomedical imaging that combines the high dynamic range of optical coherence tomography (OCT) with inherently parallel low-bandwidth image acquisition of spectral interferometry (SI), is described. DSI efficiently removes the deleterious dc background inherent in SI measurements while maintaining the parallel nature of SI. We demonstrate DSI on both synthetic and biological samples. Because DSI preserves the low-bandwidth, parallel nature of SI, it is competitive with OCT for biomedical applications in terms of image quality and acquisition rate.


Assuntos
Interferometria , Modelos Teóricos , Anatomia Transversal , Animais , Análise de Fourier , Larva/anatomia & histologia , Luz , Xenopus laevis/crescimento & desenvolvimento
11.
Appl Opt ; 42(6): 1140-4, 2003 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-12617232

RESUMO

Frequency-resolved optical gating (FROG) is a technique used to measure the intensity and phase of ultrashort laser pulses through the optical construction of a spectrogram of the pulse. To obtain quantitative information about the pulse from its spectrogram, an iterative two-dimensional phase retrieval algorithm must be used. Current algorithms are quite robust but retrieval of all the pulse information can be slow. Previous real-time FROG trace inversion work focused on second-harmonic-generation FROG, which has an ambiguity in the direction of time, and required digital signal processors (DSPs). We develop a simplified real-time FROG device based on a single-shot geometry that no longer requires DSPs. We use it and apply the principal component generalized projections algorithm to invert polarization gate FROG traces at rates as high as 20 Hz.

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