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1.
World J Microbiol Biotechnol ; 39(10): 282, 2023 Aug 17.
Artículo en Inglés | MEDLINE | ID: mdl-37589866

RESUMEN

Bloodstream infections are a growing public health concern due to emerging pathogens and increasing antimicrobial resistance. Rapid antibiotic susceptibility testing (AST) is urgently needed for timely and optimized choice of antibiotics, but current methods require days to obtain results. Here, we present a general AST protocol based on surface-enhanced Raman scattering (SERS-AST) for bacteremia caused by eight clinically relevant Gram-positive and Gram-negative pathogens treated with seven commonly administered antibiotics. Our results show that the SERS-AST protocol achieves a high level of agreement (96% for Gram-positive and 97% for Gram-negative bacteria) with the widely deployed VITEK 2 diagnostic system. The protocol requires only five hours to complete per blood-culture sample, making it a rapid and effective alternative to conventional methods. Our findings provide a solid foundation for the SERS-AST protocol as a promising approach to optimize the choice of antibiotics for specific bacteremia patients. This novel protocol has the potential to improve patient outcomes and reduce the spread of antibiotic resistance.


Asunto(s)
Bacteriemia , Técnicas Bacteriológicas , Farmacorresistencia Bacteriana , Espectrometría Raman , Bacteriemia/microbiología , Antibacterianos/farmacología , Bacterias/clasificación , Bacterias/efectos de los fármacos , Humanos , Técnicas Bacteriológicas/métodos , Cultivo de Sangre
2.
ACS Appl Mater Interfaces ; 15(26): 31692-31702, 2023 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-37339450

RESUMEN

An exciplex, which is composed of electron donor and acceptor molecules and formed by intermolecular charge transfer, is an excited-state species that is able to emit light or transfer its energy to a lower-energy emitter. In reported exciplex-based organic light-emitting diodes (OLEDs), their working mechanism is to generate exciplexes either in the bulk emitting layer (bulk exciplex) or at its interface with an electron transport layer (interface exciplex); both types give promising device performance. Here, we propose a novel strategy of creating both types of exciplexes simultaneously (dual exciplexes) for the generation of more exciplexes for better device performance as indicated in the improved photoluminescence quantum yield (PLQY). Impressively, the dual exciplex-based device with blue thermally activated delayed fluorescence (TADF) emitter 9,9-dimethyl-9,10-dihydroacridine-2,4,6-triphenyl-1,3,5-triazine (DMAC-TRZ) exhibits a record-high maximum external quantum efficiency (EQEmax) of 26.7% among the solution-processed TADF blue OLEDs. By further doping with the red-emitting phosphor emitter into the EML, the white device also gives a record-high EQEmax of 24.1% among the solution-processed TADF-phosphor hybrid white OLEDs (T-P WOLEDs) with the Commission Internationale de L'Eclairage (CIE) coordinates of (0.34, 0.42), color rendering index of 70, and correlated color temperature of 5198 K. Furthermore, both blue and white devices show an ultralow efficiency roll-off with external quantum efficiencies at a practical brightness value of 1000 cd m-2 (EQE1000) of 25.1 and 23.9%, respectively. This is the first report of employing a dual exciplex-based OLED with excellent device performance.

3.
Anal Chem ; 93(5): 2785-2792, 2021 02 09.
Artículo en Inglés | MEDLINE | ID: mdl-33480698

RESUMEN

Tuberculosis caused by Mycobacterium tuberculosis complex (MTBC) is one of the major infectious diseases in the world. Identification of MTBC and differential diagnosis of nontuberculous mycobacteria (NTM) species impose challenges because of their taxonomic similarity. This study describes a differential diagnosis method using the surface-enhanced Raman scattering (SERS) measurement of molecules released by Mycobacterium species. Conventional principal component analysis and linear discriminant analysis methods successfully separated the acquired spectrum of MTBC from those of NTM species but failed to distinguish between the spectra of different NTM species. A novel sensible functional linear discriminant analysis (SLDA), projecting the averaged spectrum of a bacterial specie to the subspace orthogonal to the within-species random variation, thereby eliminating its influence in applying linear discriminant analysis, was employed to effectively discriminate not only MTBC but also species of NTM. The successful demonstration of this SERS-SLDA method opens up new opportunities for the rapid differentiation of Mycobacterium species.


Asunto(s)
Infecciones por Mycobacterium no Tuberculosas , Mycobacterium tuberculosis , Tuberculosis , Análisis Discriminante , Humanos , Micobacterias no Tuberculosas
4.
Opt Express ; 28(19): 28218-28225, 2020 Sep 14.
Artículo en Inglés | MEDLINE | ID: mdl-32988097

RESUMEN

High color rendering index (CRI) and wide correlated color temperatures (CCTs) white LEDs (WLEDs) employing CaAlSiN3: Eu2+ and Lu3Al5O12: Ce3+ co-doped phosphor-in-glass (PiG) are demonstrated. Through fabrication using a low sintering temperature of 620°C to minimize inter-diffusion between the red phosphor and glass, and adjusting thickness of 0.5-0.7 mm to obtain the chromaticity tailorable co-doped PiG, the WLEDs exhibit high CRI of 94 and wide CCTs of 3900 K to 5300 K. This CRI is the highest yet reported for the co-doped PiG. The proposed of the co-doped PiG with good thermal stability fabricated by using a low sintering temperature may provide a novel technique to achieve high-performance WLEDs with high CRI for use in many high-quality of indoor lighting applications, especially in color inspection, clinical inspection, and gallery lighting.

5.
Sci Rep ; 10(1): 12538, 2020 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-32719444

RESUMEN

Blood stream infection is one of the major public health issues characterized with high cost and high mortality. Timely effective antibiotics usage to control infection is crucial for patients' survival. The standard microbiological diagnosis of infection however can last days. The delay in accurate antibiotic therapy would lead to not only poor clinical outcomes, but also to a rise in antibiotic resistance due to widespread use of empirical broad-spectrum antibiotics. An important measure to tackle this problem is fast determination of bacterial antibiotic susceptibility to optimize antibiotic treatment. We show that a protocol based on surface-enhanced Raman spectroscopy can obtain consistent antibiotic susceptibility test results from clinical blood-culture samples within four hours. The characteristic spectral signatures of the obtained spectra of Staphylococcus aureus and Escherichia coli-prototypic Gram-positive and Gram-negative bacteria-became prominent after an effective pretreatment procedure removed strong interferences from blood constituents. Using them as the biomarkers of bacterial metabolic responses to antibiotics, the protocol reported the susceptibility profiles of tested drugs against these two bacteria acquired from patients' blood with high specificity, sensitivity and speed.


Asunto(s)
Antibacterianos/farmacología , Bacterias/efectos de los fármacos , Bacterias/metabolismo , Espectrometría Raman , Animales , Biomarcadores/metabolismo , Escherichia coli/efectos de los fármacos , Cabras , Humanos , Pruebas de Sensibilidad Microbiana , Curva ROC , Procesamiento de Señales Asistido por Computador , Staphylococcus aureus/efectos de los fármacos
6.
J Food Prot ; 82(8): 1384-1389, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31335185

RESUMEN

Bubble tea beverages (n = 105) purchased from vendors in Taiwan were tested to determine their microbiological and chemical quality. Nearly half of the tested samples (48.6%, 51 of 105) had aerobic plate counts (APCs) higher than the Taiwan Food and Drug Administration guideline of 4.0 log CFU/mL, and 55 (52.4%) had coliform counts (most probable number [MPN]) higher than the 10 MPN/mL guideline. Escherichia coli, Salmonella, Staphylococcus aureus, sweeteners, preservatives, maleic acid, and coumarin were not detected in any sample. However, catechins were not detected to 188 mg/mL, and caffeine was 10.1 to 457.6 mg/mL. Bubble tea samples obtained from vendors in southern Taiwan had a mean APC of 2.6 log CFU/mL and a mean coliform count of 61.7 MPN/mL; these values were significantly lower (P < 0.05) than those from samples collected from vendors in northern, eastern, or central Taiwan. Samples obtained from southern Taiwan had the highest mean catechin concentrations of 21.3 mg/mL (P < 0.05). About 60% (63 of 105) of the bubble tea samples were not labeled with the origin of the tea leaves, which is in violation of Taiwanese food labeling regulations. In general, the bubble tea beverages tested had satisfactory microbial and chemical qualities.


Asunto(s)
Bebidas , Microbiología de Alimentos , , Bebidas/análisis , Catequina/análisis , Recuento de Colonia Microbiana , Análisis de los Alimentos , Taiwán , Té/microbiología
7.
J AOAC Int ; 100(4): 1086-1093, 2017 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-28330528

RESUMEN

Food detergents are commonly used in households. The main components of detergents include surfactants and water. It has been found that certain compounds, which may cause health concerns, appear in food detergents, such as alkylphenols, arsenic, and lead. After applying food detergents is when people may be exposed to various levels of these chemicals when there are residues. In this study, the Taguchi experimental design was performed to determine the possible factors that might affect the residual characteristics of food detergent on dishware, fruits, and vegetables. The results showed that the variety of detergent was found to be the most significant factor affecting the residue amounts of arsenic (62.9%) and lead (71.6%) on fruits and vegetables, whereas the concentration of detergent used affected the amount of lead residue only (10.5%). On the other hand, dishware material, the concentration of analytes, immersion time, and type of surfactant contributed to arsenic residues on dishware, whereas technical nonylphenol isomer residues on dishware increased as the concentration of spiked analyte increased. In addition, the occurrence of 1,4-dioxane, a possible human carcinogen, in household food detergents in Taiwan was also determined in this research by solid-phase microextraction and GC-MS. Among the 80 detergent samples, 71 contained different concentrations ranges of 1,4-dioxane, from 0.03 to ~3.73 µg/g. In the exposure assessment, it was estimated that the maximum amounts of 1,4-dioxane in contact with the skin from the use of household food detergent in Taiwan was 0.015 µg/kg/day.


Asunto(s)
Arsénico/análisis , Detergentes/análisis , Dioxanos/análisis , Productos Domésticos/análisis , Plomo/análisis , Taiwán
8.
IEEE Trans Vis Comput Graph ; 22(5): 1517-1526, 2016 05.
Artículo en Inglés | MEDLINE | ID: mdl-28113142

RESUMEN

We introduce a technique of calibrating camera motions in basketball videos. Our method particularly transforms player positions to standard basketball court coordinates and enables applications such as tactical analysis and semantic basketball video retrieval. To achieve a robust calibration, we reconstruct the panoramic basketball court from a video, followed by warping the panoramic court to a standard one. As opposed to previous approaches, which individually detect the court lines and corners of each video frame, our technique considers all video frames simultaneously to achieve calibration; hence, it is robust to illumination changes and player occlusions. To demonstrate the feasibility of our technique, we present a stroke-based system that allows users to retrieve basketball videos. Our system tracks player trajectories from broadcast basketball videos. It then rectifies the trajectories to a standard basketball court by using our camera calibration method. Consequently, users can apply stroke queries to indicate how the players move in gameplay during retrieval. The main advantage of this interface is an explicit query of basketball videos so that unwanted outcomes can be prevented. We show the results in Figs. 1, 7, 9, 10 and our accompanying video to exhibit the feasibility of our technique.


Asunto(s)
Gráficos por Computador , Movimiento (Física) , Baloncesto , Humanos
9.
Opt Express ; 23(15): A1024-9, 2015 Jul 27.
Artículo en Inglés | MEDLINE | ID: mdl-26367678

RESUMEN

In this paper, Lu3Al5O12:Ce3+ and CaAlSiN3: Eu2+ co-doped glass are presented as color conversion materials for white light-emitting diodes (WLEDs). Through adjusting the thickness of the glass phosphors, the chromaticity and CCT of the WLEDs follows the Planckian locus well. The WLEDs show CCT ranging from ~4000K to ~7000K with high CRI ranging from 83 to 90 due to the wide emission spectrum from the proposed glass phosphors. The glass phosphors provide an effective way to achieve chromaticity-tailorable WLEDs with high color quality for indoor lighting applications.

10.
Opt Express ; 22 Suppl 3: A671-8, 2014 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-24922375

RESUMEN

New broadband glass phosphors with excellent thermal stability were proposed and experimentally demonstrated for white light-emitting-diodes (WLEDs). The novel glass phosphors were realized through dispersing multiple phosphors into SiO2 based glass (SiO2-Na2O-Al2O3-CaO) at 680°C. Y3Al5O12:Ce³âº (YAG), Lu3Al5O12:Ce³âº (LuAG), and CaAlSiN3: Eu²âº (nitride) phosphor crystals were chosen respectively as the yellow, green, and red emitters of the glass phosphors. The effect of sintering temperature on inter-diffusion reduction between phosphor crystals and amorphous SiO2 in nitride-doped glass phosphors was studied and evidenced by the aid of high-resolution transmission electron microscopy (HRTEM). Broadband glass phosphors with high quantum-yield of 55.6% were thus successfully realized through the implementation of low sintering temperature. Proof-of-concept devices utilizing the novel broadband phosphors were developed to generate high-quality cool-white light with trisstimulus coordinates (x, y) = (0.358, 0.288), color-rending index (CRI) = 85, and correlated color temperature (CCT) = 3923K. The novel broadband glass phosphors with excellent thermal stability are essentially beneficial to the applications for next-generation solid-state indoor lighting, especially in the area where high power and absolute reliability are required.

11.
J Mater Chem B ; 2(9): 1136-1143, 2014 Mar 07.
Artículo en Inglés | MEDLINE | ID: mdl-32261349

RESUMEN

Novel nanohybrid arrays of silver (Ag)-on-silicate platelets with flexibility and three-dimensional (3D) hot-junctions (particularly in z-direction) were discovered for improving the stability of free nanoparticles and the mobility of rigid (glass or silicon-based) substrates in surface-enhanced Raman scattering (SERS) detection technology. Since the Ag nanoparticles are adsorbed on both sides of few nanometer-thick silicate platelets (single-layer exfoliated clay), the geometric arrangement of Ag on both sides of the nanoplatelets (Ag/NSP) may induce strong hot-junctions (z-direction) in reference to the pristine montmorillonite clay (multi-layers) at the thickness of ∼20 nm, measured by small molecules (adenine of DNA) and bacteria (S. aureus). Enormous red-shifts (16 nm wavelength difference) were observed between single layer and multi-layer silicate platelets, showing that huge surface plasmon enhancement comes from hot junctions in the z-direction (∼7 times higher than 2D hot-junctions of traditional SERS biochips). Further, the Ag/NSP SERS substrate displays a free floating mobility and optical transparency (less background interference), which inherently increase the contacted surface-area between the substrate and microorganisms, to enhance the SERS sensitivity. The surface modulation with a surfactant could be complimentary towards a variety of microorganisms including hydrophobic microbes, irregular-shaped microorganisms and larger biological cells due to their mutual specific surface interactions. It was anticipated to apply in the rapid detection for varied microbes with label-free and culture-free characterizations.

12.
J Food Prot ; 75(12): 2158-62, 2012 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23212012

RESUMEN

Acrylamide (AA) contents in 294 snack foods including cereal-based, root- and tuber-based, and seafood-based foods, nuts, dried beans, and dried fruits purchased in Taiwan were determined by gas chromatography-mass spectrometry in this study. The highest levels of average AA content were found in root- and tuber-based snack foods (435 µg/kg), followed by cereal-based snack foods (299 µg/kg). Rice flour-based, seafood-based, and dried fruit snack foods had the lowest average AA content (<50 µg/kg). This is the first large surveillance of AA content in snack foods in Taiwan. The results could provide important data regarding intake information from the snack foods. In addition, the results showed a great diversity of AA content in snack foods prepared from different ingredients. Rice- and seafood-based products had much lower AA than those made from other ingredients. This information could constitute a good reference for consumers to select products for healthy snacking.


Asunto(s)
Acrilamida/análisis , Contaminación de Alimentos/análisis , Cromatografía de Gases y Espectrometría de Masas/métodos , Seguridad de Productos para el Consumidor , Análisis de los Alimentos/métodos , Inocuidad de los Alimentos , Humanos , Taiwán
13.
Rapid Commun Mass Spectrom ; 23(12): 1776-82, 2009 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-19437442

RESUMEN

Little is known about melamine (MEL) analysis in children's urine. In this study, an isotopic ultra-performance liquid chromatography/tandem mass spectrometry (UPLC/MS/MS) method was developed and systematically validated for the analysis of MEL in urine. The method is easily performed and comprises acidification, solid-phase extraction (SPE) and UPLC/MS/MS analysis. (13)C(3)N(3)((15)NH(2))(3) was used as the internal standard (IS) for calibration. Transition ions m/z 127 > 85 of MEL and m/z 133 > 89 of the IS were used for quantification and m/z 127 > 68 of MEL was used for quantitative confirmation. Recovery and precision were assessed to guarantee the applicability of the method. The limit of quantification (LOQ) was 0.01 microg/mL while the calculated method detection limit was 0.006 microg/mL. The mean recoveries ranged from 96-99%. The method was then applied to analyze urine samples from children who had potentially consumed MEL-tainted dairy products during screening in Taiwan. Ten nephrolithiasis cases and 20 age- and gender-matched controls were selected for this study. Three out of the 10 nephrolithiasis cases had elevated levels of MEL. Comparatively, twenty age- and gender-matched non-nephrolithiasis controls consuming Taiwan brand milk powder all showed MEL levels lower than the detection limit except for two children with background levels of 0.02 microg/mL. The background level in these children urine samples was established by UPLC/MS/MS analysis. Positive results of urine MEL tests might be associated with nephrolithiasis in these candidates. Measurement of urine MEL concentration can be helpful in confirming MEL-related nephrolithiasis, but its clinical application needs further clarification.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Espectrometría de Masas en Tándem/métodos , Triazinas/orina , Adolescente , Isótopos de Carbono/análisis , Niño , Preescolar , Femenino , Humanos , Lactante , Masculino , Isótopos de Nitrógeno/análisis
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