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1.
Sensors (Basel) ; 23(19)2023 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-37836858

RESUMO

A flexible, non-enzymatic glucose sensor was developed and tested on a polyethylene terephthalate (PET) substrate. The sensor's design involved printing Ag (silver) as the electrode and utilizing mixtures of either gold-copper oxide-modified reduced graphene oxide (Au-CuO-rGO) or gold-copper oxide-modified reduced graphene oxide-multi-walled carbon nanotubes (Au-CuO-rGO-MWCNTs) as the carrier materials. A one-pot synthesis method was employed to create a nanocomposite material, consisting of Au-CuO-rGO mixtures, which was then printed onto pre-prepared flexible electrodes. The impact of different weight ratios of MWCNTs (0~75 wt%) as a substitute for rGO was also investigated on the sensing characteristics of Au-CuO-rGO-MWCNTs glucose sensors. The fabricated electrodes underwent various material analyses, and their sensing properties for glucose in a glucose solution were measured using linear sweep voltammetry (LSV). The LSV measurement results showed that increasing the proportion of MWCNTs improved the sensor's sensitivity for detecting low concentrations of glucose. However, it also led to a significant decrease in the upper detection limit for high-glucose concentrations. Remarkably, the research findings revealed that the electrode containing 60 wt% MWCNTs demonstrated excellent sensitivity and stability in detecting low concentrations of glucose. At the lowest concentration of 0.1 µM glucose, the nanocomposites with 75 wt% MWCNTs showed the highest oxidation peak current, approximately 5.9 µA. On the other hand, the electrode without addition of MWCNTs displayed the highest detection limit (approximately 1 mM) and an oxidation peak current of about 8.1 µA at 1 mM of glucose concentration.


Assuntos
Grafite , Nanocompostos , Nanotubos de Carbono , Cobre/química , Nanotubos de Carbono/química , Glucose/análise , Grafite/química , Eletrodos , Nanocompostos/química , Ouro/química , Óxidos , Técnicas Eletroquímicas/métodos
2.
Data Brief ; 46: 108861, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36624768

RESUMO

This data article describes a dataset of images of common Chinese deities. The dataset is divided into five categories according to the types of deities, and a total of 1314 original images were captured by smart phones from Chinese temples and through Google search engine. Each category were split into training, validation and test subsets in a ratio of 70:20:10. We rotated the pictures by 30°, 60°, 90°, 120°, 150°, and 180°; and zoomed in and out to augment the images for training and validation sets. After data enhancement, the total number of images reaches 10,786. Two models, EfficientNet-B0 and MobileNetV2, are used to identify five kinds of god images. After data augmentation, the accuracy, precision, recall, specificity and F1-score of EfficientNet-B0 were 96.15%, 96.44%, 96.18%, 96.16% and 97.60%, respectively; the accuracy, precision recall, specificity and F1-score of MobileNetV2 were 92.31%, 92.89%, 92.37%, 92.33% and 95.19%, respectively. This dataset can be used as a reference for traditional Chinese god statue images, and can also be used for object detection and image classification through machine learning and deep learning methods.

3.
Opt Express ; 30(26): 47082-47092, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558645

RESUMO

Phosphor-converted white light emitting diodes (pc-WLEDs) are used worldwide for an extensive amount of applications. The device is a complex combination of various components that introduce various technical issues: materials, electrical, chemical, thermal, and so on. All of these combined to obtain a targeted optical characteristic. While most of the pc-WLEDs are sufficient for basic illumination performance, there are still many issues to improve the pc-WLED performance. In this work, we deal with the incorporation of micron size particles of titanium oxide (TiO2) in silicone encapsulant that contains yttrium aluminum garnet (YAG) phosphor in remote phosphor pc-WLED. Based on the light output and the scattering spatial distribution measurements of the phosphor plates, we have found that several essential performance indices, like the color uniformity, the efficiency, and the amount of phosphor for the pc-WLEDs, can be adjusted by tuning the amount of TiO2 particles and thus be optimized. With a comprehensive model using a Monte-Carlo ray tracing process combined with the Mie scattering theory, two TiO2 loading conditions are revealed. The first one is the sparse condition that the TiO2 particles act as the scattering particles such as to increase the output flux to improve the efficiency of YAG. The second one is the dense condition that the TiO2 particles act more as barrier particles such so to decrease the output flux.

4.
J Hum Kinet ; 62: 231-240, 2018 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-29922394

RESUMO

This study examined the effects of one single bout daily versus triple bouts of resistance exercise for 12 weeks on muscular strength and anaerobic performance of the upper body. Twenty young male adults (age: 22.0 ± 1.0 years, bench press: 44.0 ± 10.3 kg) were randomly assigned to a single bout (SB) or triple bouts (TB) of resistance exercise group. Maximal strength and anaerobic performance of the upper body using the bench press (one-repetition maximum) and the modified 30 s Wingate test were determined before and after the intervention. Additionally, changes in lactate levels before and after the Wingate test were measured. Although the SB and TB groups showed a significant increase in maximal strength (post-intervention, SB: 67.2 ± 9.2 and TB: 67.6 ± 7.6 kg, respectively) compared with the values at pre-intervention (SB: 44.6 ± 11.4 and TB: 43.9 ± 8.7 kg, respectively), there was no significant difference for this variable between the two groups post-intervention (p > 0.05). The anaerobic performance of the upper body in the SB and TB groups also displayed improvements without significant difference between the two groups after the completion of different training regimes. On the basis of the same training volume, multiple bouts of resistance training showed similar improvements in maximal strength and anaerobic performance to one bout of resistance training in young adult men without prior experience in resistance training.

5.
Org Biomol Chem ; 13(47): 11550-60, 2015 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-26463681

RESUMO

A concise synthesis of single components of C2 sulfated oligomannans including trimers, tetramers, and pentamers is reported. The synthesis features the application of the DMF-modulation method for the participatory thiomannoside donors in 1,2-transα-glycosidic bond formation. The obtained oligomannans were fully characterized using (1)H, (13)C, COSY, and HSQC NMR spectroscopy.


Assuntos
Mananas/síntese química , Sulfatos/síntese química , Dimerização , Dissacarídeos/síntese química , Dissacarídeos/química , Espectroscopia de Ressonância Magnética , Mananas/química , Sulfatos/química
6.
Org Biomol Chem ; 12(8): 1184-97, 2014 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-24382624

RESUMO

The major challenge in carbohydrate synthesis is stereochemical control of glycosidic bond formation. Different glycosylation methods have been developed that are based on the modulation effect of external nucleophiles. This review highlights the development, synthetic application, challenges and outlook of the modulated glycosylation methods.


Assuntos
Técnicas de Química Sintética/métodos , Glicosídeos/química , Glicosilação , Glicosídeos/síntese química , Estereoisomerismo
7.
Proteomics ; 12(3): 380-90, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-22144111

RESUMO

Titanium dioxide (TiO2) has been widely used for phosphopeptide enrichment. Several approaches have been reported to produce magnetic TiO2 affinity probes. In this report, we present a facile approach to immobilize TiO2 onto poly(acrylic acid)-functionalized magnetic carbon-encapsulated iron nanoparticles as affinity probes for efficient enrichment of phosphopeptides. By using the new magnetic TiO2 affinity probes, denoted as TiO2-coated Fe@CNPs, rapid and effective MALDI-TOF MS profiling of phosphopeptides was demonstrated in different model systems such as tryptic digests of ß-casein, and complex ß-casein/BSA mixture. The TiO2-coated Fe@CNPs out-performed the commercial TiO2-coated magnetic beads for detection of phosphopeptides from tryptic digests of ß-casein/BSA mixture with a molar ratio of 1:100. The new TiO2-coated magnetic probes were also proven to be applicable for real life samples. The magnetic TiO2-coated Fe@CNPs were employed to selectively isolate phosphopeptides from tryptic digests of HeLa cell lysates and out-performed the commercial magnetic TiO2 beads in the number of identified phosphopeptides and phosphorylation sites. In a 200-µg equivalent of HeLa cell lysates, we identified 1415 unique phosphopeptides and 1093 phosphorylation sites, indicating the good performance of the new approach.


Assuntos
Nanopartículas de Magnetita/química , Fosfopeptídeos/química , Titânio/química , Cromatografia de Afinidade/métodos , Células HeLa , Humanos , Ferro/química , Fosforilação , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos
8.
Analyst ; 136(9): 1922-7, 2011 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-21403954

RESUMO

Simultaneous detection of multiply and singly phosphorylated peptides using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) is challenging because of suppression effects during ionization. In oder to overcome this problem, this study presents a new approach to improve the detection of phosphopeptides by stepwise enrichment using polyarginine-coated (PA-coated) and titanium dioxide-coated (TiO(2)-coated) nanodiamonds for fractionation of multiply and singly phosphorylated peptides prior to on-probe MALDI MS analysis. The feasibility of this approach was demonstrated using synthetic peptides containing different numbers of phosphate groups, tryptic digests of α-casein, ß-casein, and complex protein mixtures. The high specificity of the approach is shown in its effective enrichment and fractionation of phosphopeptides from the digest of ß-casein and bovine serum albumin at a molar ratio as low as 1 : 1000, which out-performs the commercial Fe(3+)-IMAC and TiO(2) isolation kits. It offers a simple and effective alternative for the fractionation and identification of multiply and singly phosphorylated peptides by MALDI MS and allows for deduction of more information from limited starting materials.


Assuntos
Nanodiamantes/química , Fosfopeptídeos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Sequência de Aminoácidos , Animais , Caseínas/química , Caseínas/isolamento & purificação , Bovinos , Humanos , Dados de Sequência Molecular , Peptídeos/química , Fosforilação , Soroalbumina Bovina/química , Soroalbumina Bovina/isolamento & purificação , Titânio/química , Tripsina/química
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