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1.
Opt Express ; 31(13): 21107-21117, 2023 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-37381218

RESUMO

Recently, fluorescence-based optical techniques have emerged as a powerful tool to probe information in the mammalian brain. However, tissue heterogeneities prevent clear imaging of deep neuron bodies due to light scattering. While several up-to-date approaches based on ballistic light allow to retrieve information at shallow depths inside the brain, non-invasive localization and functional imaging at depth still remains a challenge. It was recently shown that functional signals from time-varying fluorescent emitters located behind scattering samples could be retrieved by using a matrix factorization algorithm. Here we show that the seemingly information-less, low-contrast fluorescent speckle patterns recovered by the algorithm can be used to locate each individual emitter, even in the presence of background fluorescence. We test our approach by imaging the temporal activity of large groups of fluorescent sources behind different scattering phantoms mimicking biological tissues, and through a brain slice with a thickness of ∼200 µm.


Assuntos
Algoritmos , Diagnóstico por Imagem , Animais , Fluorescência , Imagens de Fantasmas , Encéfalo/diagnóstico por imagem , Corantes , Mamíferos
2.
ArXiv ; 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36824429

RESUMO

Recently, fluorescence-based optical techniques have emerged as a powerful tool to probe information in the mammalian brain. However, tissue heterogeneities prevent clear imaging of deep neuron bodies due to light scattering. While several up-to-date approaches based on ballistic light allow to retrieve information at shallow depths inside the brain, non-invasive localization and functional imaging at depth still remains a challenge. It was recently shown that functional signals from time-varying fluorescent emitters located behind scattering samples could be retrieved by using a matrix factorization algorithm. Here we show that the seemingly information-less, low-contrast fluorescent speckle patterns recovered by the algorithm can be used to locate each individual emitter, even in the presence of background fluorescence. We test our approach by imaging the temporal activity of large groups of fluorescent sources behind different scattering phantoms mimicking biological tissues, and through a brain slice with a thickness of ~200 micron.

3.
Sci Rep ; 9(1): 9686, 2019 07 04.
Artigo em Inglês | MEDLINE | ID: mdl-31273263

RESUMO

A novel mesoporous silica with enhanced phosphonic functional groups (PFGs) and without any silane agents was provided by Sol-Gel technique for selective adsorption of U(VI) from aqueous solutions (AqS). The absorbent was synthesized based on the achieving the four best performance characteristics including availability, economically, adsorption efficiency, and selectivity which are undoubtedly defined the usefulness of the adsorbents. The sorption results exhibited the highest uranium adsorption capacity, qe, of 820.7 mg/g at pH ≈ 8 which indicated the adsorbent is the best alternative for uranium adsorption from the nearly neutral solutions such as seawater. The recovery percentages by the adsorbent in the aqueous environments involving other elements such as Mg, Cd, Hg, As, Ca, Na, Ni and the salty environment with high concentration of Cl- ions are indicated that the adsorbent presents the acceptable selectivity for uranium adsorption from the AqS such as industrial wastewater. Several activities and factors including removing the silane agents, using sodium metasilicate as an available and low-cost source of silica, and using the Sol-gel method as an unexpansive synthesis technique caused to reduce the synthesis costs from 222.787 EUR/kg for the template method to 60.078 EUR/kg for Sol-gel method which confirm the synthesis of a cost-effective adsorbent.

4.
Sci Rep ; 7(1): 11675, 2017 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-28916797

RESUMO

Enhanced phosphonic functional group (PFG)-based mesoporous silicas (MSs) were synthesized by hydrothermal method for uranium [U(VI)] selective adsorption from aqueous solutions. Considering that PFGs are directly related to U(VI) adsorption, the main idea of this research was to synthesize enhanced PFG-MSs and consequently enhance U(VI) adsorption. We synthesized two kinds of MSs based on acetic and phosphoric acids at weakly acidic pH, which allows high-loading phosphonic functionality. The main sodium and phosphonic functionality sources were sodium metasilicate and diethylphosphatoethyltriethoxysilane (DPTS). Adsorption experiment results exhibit enhanced U(VI) adsorption capacity from 55.75 mg/g to 207.6 mg/g for acetic and phosphoric acids, respectively. This finding was due to the enhancement of PFGs by phosphoric acids. The highest adsorption selectivity was 79.82% for U(VI) among the six different elements, including Pb, As, Cu, Mo, Ni, and K. Structural characterization of the samples was performed by Fourier transform infrared, X-ray diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Brunauer-Emmett-Teller analysis methods. Element concentrations were measured by inductively coupled plasma optical emission spectrometry. Several parameters affecting adsorption capacity, including pH, contact time, initial U(VI) concentration and solution volume, and adsorbent concentration, were also investigated.

5.
Man Ther ; 24: 18-24, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27317502

RESUMO

BACKGROUND: The Lateral Scapular Slide Test is a static test used in clinical settings to assess medio-lateral inferior angle displacement and scapular asymmetry at three different degrees of shoulder abduction. However, there is no evidence in the literature about the reliability and diagnostic accuracy of a modified LSST (arm elevation in the scapular plane with loading) in a symptomatic population. OBJECTIVE: To assess the intra- and inter-rater reliability, agreement, and diagnostic accuracy of the MLSST ​ (Modified Lateral Scapular Slide Test) in subjects with and without shoulder symptoms. A new test position is examined, in which the arm is held in 90° of elevation in the scapular plane with 1 kg load. DESIGN: Within day intra- and inter-rater reliability, agreement, and diagnostic accuracy study. METHOD: Participants included 25 (42 ± 2.7 years) subjects with shoulder symptoms and 25 (40 ± 2.1 years) asymptomatic control subjects. Two raters, blinded to each other's outcomes, measured the distance between the inferior scapular angle and T7 at arms by the side, hands on hips and 90° of arm elevation in the scapular plane with 1 kg load. Measurements were performed twice, bilaterally. Intraclass correlation coefficient (ICC), minimal detectable change (MDC95%) and diagnostic accuracy were calculated. RESULTS: The ICCs for intra- and inter-rater reliability were good to high in both shoulders of symptomatic and asymptomatic groups. The MDC95% in the symptomatic group ranged between 0.67 and 1.40 cm in the symptomatic shoulder and 0.72-1.16 cm in the asymptomatic shoulder. The asymptomatic group presented a MDC95% ranging between 0.63 and 1.52 cm in the dominant and 0.60-1.41 cm in the non dominant shoulder. Positive and negative likelihood ratios ranged between 0.67-5.50 and 0.81-1.11, respectively. CONCLUSION: The MLSST had good reliability and agreement properties to assess scapular position in both groups. However, no test position had clinical utility as a diagnostic criterion for shoulder pathology.


Assuntos
Fenômenos Biomecânicos/fisiologia , Artropatias/diagnóstico , Amplitude de Movimento Articular/fisiologia , Escápula/lesões , Escápula/fisiopatologia , Articulação do Ombro/diagnóstico por imagem , Articulação do Ombro/fisiopatologia , Adulto , Antropometria/métodos , Feminino , Humanos , Masculino , Reprodutibilidade dos Testes
6.
Br J Sports Med ; 44(4): 289-93, 2010 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18812417

RESUMO

BACKGROUND: Lateral scapular slide test (LSST) quantitatively measures the distance between thoracic spine (T7) and inferior angle of scapula. OBJECTIVE: In this study, the intra-rater reliability, inter-rater reliability and diagnostic accuracy of LSST were measured using a caliper. METHODS: Three measurements of each test position were obtained bilaterally. Intraclass correlation coefficient (ICC) (2.1), 95% CI and 2 SEMs were calculated for intra-rater and inter-rater reliability of the absolute scapular distance. Sensitivity, specificity, positive and negative likelihood ratios were determined. RESULTS: 27 people with and 30 people without shoulder pain participated. The mean age (SD) for the participant was 47.7 (11.6) years and 33.5 (11.7) years, respectively. The ICCs for intra-rater reliability were high. A range of poor to good ICCs was found for inter-rater reliability. The 2 SEMs ranged from 4.6 to 7.9 mm for intra-rater reliability and from 6.8 to 13.4 mm for inter-rater reliability for people with shoulder pain. Positive and negative likelihood ratios from 0.94 to 1.22 and from 0.21 to 2.5, respectively, were demonstrated. CONCLUSION: SST did not show a consistent high reliability. The diagnostic accuracy of the LSST was low, which questions the clinical importance of the tests outcomes.


Assuntos
Antropometria/métodos , Artropatias/patologia , Escápula/patologia , Articulação do Ombro/patologia , Adolescente , Adulto , Idoso , Estudos Transversais , Humanos , Pessoa de Meia-Idade , Variações Dependentes do Observador , Sensibilidade e Especificidade , Adulto Jovem
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