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1.
Guang Pu Xue Yu Guang Pu Fen Xi ; 37(2): 651-8, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30292188

RESUMEN

The heart rate (HR) measurements based on the camera (visible light) can be used to detect HR in non-contact mode, which has great application prospects both in the clinical application and home health care. However, CMOS sensors equipped with "rolling shutters", which distinguishes different lines per frame to become light sensitive at different moments in time, and stylized dithering of image acquisition (IMAQ) time caused by different computer programs running in the background will greatly influence the accuracy of the measured HR. In this paper, we analyze the phase error caused by CMOS sensor and the system error introduced by system sampling clock jitters. According to derivation, we propose two methods, amplitude-frequency superposition and a cubic spline interpolation reconstruction method based on actual schedules, that can be widely utilized in computer vision to overcome the camera phase error and sampling time fluctuation error. Amplitude of signal is analyzed and processed in amplitude-frequency domain in the method of amplitude-frequency superposition, which ignores the signal phase. Thus it can eliminate the phase error effectively. The cubic spline interpolation reconstruction method based on actual schedules can reconstructed the non-uniform sampling of images as uniform ones, so it can eliminate the system error involved by the system clock jitters. What's more, the properties of the methods are tested by applying them to both simulation experiments and real HR measurements. In the simulation, amplitude of measured signal is improved 4.58% relative to the amplitude measured without the method of amplitude-frequency superposition; root mean square error of signal's frequency, detected by the cubic spline interpolation reconstruction method based on actual schedules, is reduced more than 30%. In the real HR measurements, the amplitude of HR is raised to 33.5% relatively based on amplitude-frequency superposition. And the accuracy of HR is raised to approximately 40% by the method of cubic spline interpolation reconstruction method based on actual schedules. Therefore, the simulation experiments and real HR measurement proof that we can effectively eliminate the camera phase error based on the amplitude-frequency superposition extraction method, and the cubic spline interpolation based on the timetable method can effectively reduce the random error in IMAQ due to system clock jitters. These methods can both be widely used in dynamic signal detection based on machine vision.


Asunto(s)
Algoritmos , Frecuencia Cardíaca
3.
Huan Jing Ke Xue ; 33(7): 2470-4, 2012 Jul.
Artículo en Chino | MEDLINE | ID: mdl-23002629

RESUMEN

Crude laccase extracted from the Amillariella mellea fermentation broth was directly used to catalyze the degradation of 2,4-chlorophenol (2,4-DCP) and 2-chlorophenol (2-CP). The effects of reaction time, pH, temperature, chlorophenol concentration, and laccase dosage on the removal efficiency of chlorophenols were investigated. Optimal catalytic conditions for the degradation of chlorophenols were obtained and the degradation kinetics were analyzed. The results indicated that the crude laccase from Amillariella mellea was able to effectively degrade 2,4-DCP and 2-CP, with higher catalytic ability towards 2,4-DCP degradation. For 2,4-DCP degradation, the optimal temperature was 40 degrees C, the optimal substrate concentration was 75 mg x L(-1), the optimal enzyme dosage was 0. 1 U x mL(-1), and the optimal pH was 6.5. Under these conditions, the maximum degradation rate of 2,4-DCP reached > 97% after 10 h. For 2-DCP degradation, the optimal temperature was 50 degrees C, the optimal substrate concentration was 100 mg x L(-1), the optimal enzyme dosage was 0.1 U x mL(-1), and the optimal pH was 6. Under these conditions, the maximum degradation rate of 2-CP was over 93% after 10 h. The reaction process of laccase-catalyzed 2,4-DCP and 2-CP degradation obeyed the first-order kinetics equation. The laccase from Amillariella mellea was able to effectively degrade chlorophenols, indicating its potential application value in phenolic pollutant control and environmental protection.


Asunto(s)
Clorofenoles/aislamiento & purificación , Hongos/enzimología , Lacasa/metabolismo , Catálisis , Clorofenoles/metabolismo , Hongos/clasificación , Eliminación de Residuos Líquidos/métodos , Aguas Residuales/química
4.
Huan Jing Ke Xue ; 33(2): 495-8, 2012 Feb.
Artículo en Chino | MEDLINE | ID: mdl-22509587

RESUMEN

Laccase extracted from the Amillariella mellea fermentation catalytic decolored on two common anthraquinone dyes: Reactive Brilliant Blue KN-R and Reactive Brilliant Blue X-BR which is broadly used in the printing and dyeing industry and obtained the optimal catalytic decolorizing conditions. The results showed that optimum temperature of Reactive Brilliant Blue KN-R decolorization was 30 degrees C, the optimum dye concentrations was 80 mg x L(-1), the optimum enzyme dosage was 0.25 U x mL(-1), and the optimum pH was 5. Under this optimal conditions, the maximum decolorization rate of Reactive Brilliant Blue KN-R was over 90%. The optimum temperature Reactive Brilliant Blue X-BR decolorization was 30 degrees C, the optimum dye concentrations was 50 mg x L(-1), the optimum enzyme dosage was 0.5 U x mL(-1), and the optimum was pH 4. Under the optimal conditions, the maximum decolorization rate of Reactive Brilliant Blue X-BR was over 70%. The decolorization on the two common industrial dyes by crude enzyme from Amillariella mellea fermentation obtained a good results. The results indicated that the decoloration on anthraquinone dyes by laccase from Amillariella mellea has a potential value in the printing and dyeing industry.


Asunto(s)
Antraquinonas/aislamiento & purificación , Colorantes/aislamiento & purificación , Hongos/enzimología , Lacasa/metabolismo , Eliminación de Residuos Líquidos/métodos , Antraquinonas/metabolismo , Bencenosulfonatos/aislamiento & purificación , Bencenosulfonatos/metabolismo , Colorantes/metabolismo , Hongos/clasificación , Industria Textil , Aguas Residuales/química
5.
Nat Prod Res ; 23(6): 527-32, 2009.
Artículo en Inglés | MEDLINE | ID: mdl-19384729

RESUMEN

Three di-O-caffeoylquinic acid derivatives were isolated from the ethanol extracts of the heads of Cynara scolymus L. Their structures were elucidated based on spectra analyses.


Asunto(s)
Cynara scolymus/química , Flores/química , Extractos Vegetales/aislamiento & purificación , Ácido Quínico/análogos & derivados , Etanol , Espectroscopía de Resonancia Magnética , Estructura Molecular , Extractos Vegetales/química , Ácido Quínico/química , Ácido Quínico/aislamiento & purificación
7.
J Clin Invest ; 109(1): 69-78, 2002 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-11781352

RESUMEN

It is estimated that up to one in five individuals develop pituitary gland tumors. Despite the common occurrence of these tumors, the pathogenetic mechanisms underlying their development remain largely unknown. We report the identification of a novel pituitary tumor-derived, N-terminally truncated isoform of FGF receptor-4 (ptd-FGFR4). The corresponding mRNA results from alternative transcription initiation and encodes a polypeptide that lacks a signal peptide and the first two extracellular Ig-like domains. ptd-FGFR4 has a distinctive cytoplasmic residence, is constitutively phosphorylated, and is transforming in vitro and in vivo. Here we show that targeted expression of ptd-FGFR4, but not FGFR4, results in pituitary tumors that morphologically recapitulate the human disease.


Asunto(s)
Neoplasias Hipofisarias/etiología , Neoplasias Hipofisarias/genética , Receptores de Factores de Crecimiento de Fibroblastos/genética , Receptores de Factores de Crecimiento de Fibroblastos/metabolismo , Células 3T3 , Animales , Secuencia de Bases , Transformación Celular Neoplásica , ADN de Neoplasias/genética , Expresión Génica , Humanos , Ratones , Ratones Desnudos , Ratones Transgénicos , Datos de Secuencia Molecular , Fragmentos de Péptidos/genética , Fragmentos de Péptidos/metabolismo , Fosforilación , Neoplasias Hipofisarias/metabolismo , Neoplasias Hipofisarias/patología , Isoformas de Proteínas/genética , Isoformas de Proteínas/metabolismo , ARN Mensajero/genética , ARN Mensajero/metabolismo , ARN Neoplásico/genética , ARN Neoplásico/metabolismo , Receptor Tipo 4 de Factor de Crecimiento de Fibroblastos , Eliminación de Secuencia
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