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1.
ACS Meas Sci Au ; 2(6): 576-583, 2022 Dec 21.
Artículo en Inglés | MEDLINE | ID: mdl-36785775

RESUMEN

Scanning electrochemical microscopy (SECM) is one of the scanning probe techniques that has attracted considerable attention because of its ability to interrogate surface morphology or electrochemical reactivity. However, the quality of SECM images generally depends on the sizes of the electrodes and many uncontrollable factors. Furthermore, manipulating fragile glass ultramicroelectrodes and blurred images sometimes frustrate researchers. To overcome the challenges of modern SECM, we developed novel soft gold probes and then established the AI-assisted methodology for image fusion. A novel gold microelectrode probe with high softness was developed to scan fragile samples. The distribution of EGFR (protein biomarker) in oral cancer was investigated. Then, we fused the optical microscopic and SECM images to enhance the image quality using Matlab software. However, thousands of fused images were generated by changing the parameters for image fusion, which is annoying for researchers. Thus, a deep learning model was built to select the best-fused images according to the contrast and clarity of the fused images. Therefore, the quality of the SECM images was improved using a novel soft probe and combining the image fusion technique. In the future, a new scanning probe with AI-assisted fused SECM image processing may be interpreted more preciously and contribute to the early detection of cancers.

2.
J Org Chem ; 85(8): 5570-5579, 2020 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-32249566

RESUMEN

Two new classes of heteroarene-fused [1,2,4]thiadiazole and [1,2,4]selenadiazole are synthesized through the iodine-mediated [3 + 2] oxidative cyclization of 2-aminoheteroarenes and isothiocyanates/isoselenocyanates. This oxidative [3 + 2] annulation strategy is highly regiospecific to proceed a selective C-N bond formation at the endo-nitrogen of 2-aminoheteroarenes followed by an intramolecular oxidative N-S/N-Se bond formation. It is the first example of an I2-mediated oxidative nitrogen-selenium (N-Se) bond formation.

3.
ACS Comb Sci ; 21(4): 269-275, 2019 04 08.
Artículo en Inglés | MEDLINE | ID: mdl-30775908

RESUMEN

Base-controlled regioselective synthesis of 2-imino thiazolines and 2-thioxoimidazolin-4-ones was achieved to use a one-pot reaction between chiral amino esters, isothiocyanates, and α-bromoketones/alkyl halides. This three-component coupling reaction in acetonitrile provides 2-imino thiazolines, whereas the formation of 2-thioxoimidazolin-4-ones was observed under basic conditions at ambient temperature. The corresponding products were obtained in good to excellent yield with broad substrate scope. Isolation of thiourea and thiohydantoin intermediates disclosed the course of the reaction mechanism.


Asunto(s)
Imidazolidinas/síntesis química , Tiazoles/síntesis química , Ésteres/química , Imidazolidinas/química , Iminas/química , Isotiocianatos/química , Cetonas/química , Estructura Molecular , Oxidación-Reducción , Estereoisomerismo , Tiazoles/química , Tiohidantoínas/química , Tiourea/química
4.
Carbohydr Polym ; 170: 281-288, 2017 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-28521998

RESUMEN

Chitosan-g-poly[(2-dimethylamino)ethyl methacrylate] was investigated as a CO2-switchable emulsifier in this study. Poly(2-dimethylamino)ethyl methacrylate (PDMAEMA) was prepared by atom transfer radical polymerization followed by grafting to chitosan (CS). The CO2-responsiveness and reversible CO2-switchable temperature- and pH-sensitive behavior of PDMAEMA and CS-g-PDMAEMA were investigated as emulsifiers via simple CO2 and N2 bubbling. The lower critical solution temperatures (LCSTs) of PDMAEMA and CS-g-PDMAEMA aqueous solutions both increased as pH decreased to about pH 7.3, at which point the LCSTs disappeared. At elevated temperatures (e.g. 60°C), CO2 bubbling removed the turbidity in CS-g-PDMAEMA aqueous solution and N2 bubbling restored turbidity. The presence of CS-g-PDMAEMA in a two-phase solution of n-butanol/deionized water enabled the formation of a completely emulsified single phase after CO2 bubbling, which reverted to a two-phase solution on N2 bubbling. Overall, CS-g-PDMAEMA has potential as a CO2-switchable emulsifier.


Asunto(s)
Dióxido de Carbono/química , Quitosano/química , Emulsionantes/química , Metacrilatos/química , Polimerizacion
5.
Sensors (Basel) ; 16(7)2016 Jul 11.
Artículo en Inglés | MEDLINE | ID: mdl-27409621

RESUMEN

Most individuals with intellectual disabilities (ID) demonstrate problems in learning and movement coordination. Consequently, they usually have difficulties in activities such as standing, walking, and stair climbing. To monitor the physical impairments of these children, regular gross motor evaluation is crucial. Straight-line level walking is the most frequently used test of their mobility. However, numerous studies have found that unless the children have multiple disabilities, no significant differences can be found between the children with ID and typically-developed children in this test. Stair climbing presents more challenges than level walking because it is associated with numerous physical factors, including lower extremity strength, cardiopulmonary endurance, vision, balance, and fear of falling. Limited ability in those factors is one of the most vital markers for children with ID. In this paper, we propose a sensor-based approach for measuring stair-walking performance, both upstairs and downstairs, for adolescents with ID. Particularly, we address the problem of sensor calibration to ensure measurement accuracy. In total, 62 participants aged 15 to 21 years, namely 32 typically-developed (TD) adolescents, 20 adolescents with ID, and 10 adolescents with multiple disabilities (MD), participated. The experimental results showed that stair-walking is more sensitive than straight-line level walking in capturing gait characteristics for adolescents with ID.


Asunto(s)
Discapacidad Intelectual/fisiopatología , Caminata/fisiología , Acelerometría , Adolescente , Análisis de Varianza , Humanos , Reproducibilidad de los Resultados , Rotación , Procesamiento de Señales Asistido por Computador , Adulto Joven
6.
PLoS One ; 11(3): e0151772, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-26986626

RESUMEN

PURPOSE: We sought to imitate angiographic cerebral circulation time (CCT) and create a similar index from baseline CT perfusion (CTP) to better predict vasospasm in patients with subarachnoid hemorrhage (SAH). METHODS: Forty-one SAH patients with available DSA and CTP were retrospectively included. The vasospasm group was comprised of patients with deterioration in conscious functioning and newly developed luminal narrowing; remaining cases were classified as the control group. The angiography CCT (XA-CCT) was defined as the difference in TTP (time to peak) between the selected arterial ROIs and the superior sagittal sinus (SSS). Four arterial ROIs were selected to generate four corresponding XA-CCTs: the right and left anterior cerebral arteries (XA-CCTRA2 and XA-CCTLA2) and right- and left-middle cerebral arteries (XA-CCTRM2 and XA-CCTLM2). The CCTs from CTP (CT-CCT) were defined as the differences in TTP from the corresponding arterial ROIs and the SSS. Correlations of the different CCTs were calculated and diagnostic accuracy in predicting vasospasm was evaluated. RESULTS: Intra-class correlations ranged from 0.96 to 0.98. The correlations of XA-CCTRA2, XA-CCTRM2, XA-CCTLA2, and XA-CCTLM2 with the corresponding CT-CCTs were 0.64, 0.65, 0.53, and 0.68, respectively. All CCTs were significantly prolonged in the vasospasm group (5.8-6.4 s) except for XA-CCTLA2. CT-CCTA2 of 5.62 was the optimal cut-off value for detecting vasospasm with a sensitivity of 84.2% and specificity 82.4. CONCLUSION: CT-CCTs can be used to interpret cerebral flow without deconvolution algorithms, and outperform both MTT and TTP in predicting vasospasm risk. This finding may help facilitate management of patients with SAH.


Asunto(s)
Circulación Cerebrovascular/fisiología , Hemorragia Subaracnoidea/fisiopatología , Vasoespasmo Intracraneal/fisiopatología , Angiografía de Substracción Digital/métodos , Femenino , Humanos , Masculino , Persona de Mediana Edad , Imagen de Perfusión/métodos , Hemorragia Subaracnoidea/complicaciones , Hemorragia Subaracnoidea/diagnóstico por imagen , Tomografía Computarizada por Rayos X/métodos , Vasoespasmo Intracraneal/diagnóstico por imagen , Vasoespasmo Intracraneal/etiología
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