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1.
Inorg Chem ; 63(15): 6798-6812, 2024 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-38566011

RESUMEN

The impact of variable valence A-sites on the redox property and reactivity of Ln2Ce2O7 compounds in soot particulate combustion has been investigated. It was observed that Yb2Ce2O7, Y2Ce2O7, and Gd2Ce2O7 formed a rare earth C-type phase, while Tb2Ce2O7 formed a solid solution phase. Both Tb2Ce2O7 and Yb2Ce2O7 possess dual valence state A-sites, resulting in significantly more surface vacancies. Additionally, the advantageous solid solution phase structure of Tb2Ce2O7 leads to even more surface vacancies than Yb2Ce2O7, which is crucial to generate active oxygen sites. Moreover, the introduction of NO into the reaction feed enhances combustion activity by producing active surface monodentate nitrates. A catalyst with higher numbers of surface vacancies exhibits improved NO oxidation ability and better NO2 utilization efficiency. Consequently, the Tb2Ce2O7 compound demonstrates not only the best soot combustion activity, but also an optimal NOx-assistance effect. Therefore, it is concluded that variable valence A-site is the intrinsic factor to improve the reactivity of Ln2Ce2O7 catalysts.

2.
Phys Chem Chem Phys ; 26(2): 974-984, 2024 Jan 03.
Artículo en Inglés | MEDLINE | ID: mdl-38088058

RESUMEN

The quantity of surface oxygen vacancies/defects is critical to promote the reactivity of metal oxide catalysts. Therefore, for the controlled engineering of Bi2Zr2O7 with rich surface defects for soot combustion, four different methods have been adopted. Bi2Zr2O7 compounds with a defective fluorite phase but with varied surface vacancy concentrations have been successfully synthesized by various methods. The best catalyst (Bi2Zr2O7-CP) was fabricated by a facile co-precipitation method. Both O2- and O22- were the active surface sites whose number positively correlated to the number of surface oxygen vacancies and determined the activity. Moreover, a sample with more surface vacancies usually had weaker Zr-O bonds, which could be the intrinsic factor to enhance the activity. In addition, a novel and simple method has been developed to accurately titrate the absolute amount of soot reactive oxygen sites and calculate the TOF values. In conclusion, by optimizing the preparation methods, Bi2Zr2O7 catalysts with rich surface defects can be tuned, which may help in designing more applicable soot oxidation catalysts.

3.
Oral Dis ; 2024 Feb 26.
Artículo en Inglés | MEDLINE | ID: mdl-38409677

RESUMEN

OBJECTIVES: A zinc-finger transcription factor family comprising specificity proteins (SPs) and Krüppel-like factor proteins (KLFs) plays an important role in dentin development and regeneration. However, a systematic regulatory network involving SPs/KLFs in odontoblast differentiation has not yet been described. This review examined the expression patterns of SP/KLF gene family members and their current known functions and mechanisms in odontoblast differentiation, and discussed prospective research directions for further exploration of mechanisms involving the SP/KLF gene family in dentin development. MATERIALS AND METHODS: Relevant literature on SP/KLF gene family members and dentin development was acquired from PubMed and Web of Science. RESULTS: We discuss the expression patterns, functions, and related mechanisms of eight members of the SP/KLF gene family in dentin development and genetic disorders with dental problems. We also summarize current knowledge about their complementary or synergistic actions. Finally, we propose future research directions for investigating the mechanisms of dentin development. CONCLUSIONS: The SP/KLF gene family plays a vital role in tooth development. Studying the complex complementary or synergistic interactions between SPs/KLFs is helpful for understanding the process of odontoblast differentiation. Applications of single-cell and spatial multi-omics may provide a more complete investigation of the mechanism involved in dentin development.

4.
Sheng Wu Yi Xue Gong Cheng Xue Za Zhi ; 40(2): 365-372, 2023 Apr 25.
Artículo en Zh | MEDLINE | ID: mdl-37139770

RESUMEN

Blood glucose monitoring has become the weakest point in the overall management of diabetes in China. Long-term monitoring of blood glucose levels in diabetic patients has become an important means of controlling the development of diabetes and its complications, so that technological innovations in blood glucose testing methods have far-reaching implications for accurate blood glucose testing. This article discusses the basic principles of minimally invasive and non-invasive blood glucose testing assays, including urine glucose assays, tear assays, methods of extravasation of tissue fluid, and optical detection methods, etc., focuses on the advantages of minimally invasive and non-invasive blood glucose testing methods and the latest relevant results, and summarizes the current problems of various testing methods and prospects for future development trends.


Asunto(s)
Glucemia , Diabetes Mellitus , Humanos , Automonitorización de la Glucosa Sanguínea/métodos , Diabetes Mellitus/diagnóstico , Monitoreo Fisiológico/métodos , Lágrimas
5.
Nanoscale ; 14(3): 642-652, 2022 Jan 20.
Artículo en Inglés | MEDLINE | ID: mdl-34935821

RESUMEN

Dentinal tubule (DT) occlusion by desensitizing agents has been widely applied to inhibit the transmission of external stimuli that cause dentin hypersensitivity (DH). However, most desensitizing agents merely accomplish porous blocking or the formation of a superficial tubular occlusion layer, resulting in a lack of mechanical and acid resistance and long-term stability. Herein, combining biomimetic mineralization and mineral overgrowth of the dentinal matrix was shown to effectively occlude DTs, resulting in the formation of a compact and deep occluding mineral layer that is strongly bound to the organic matrix on tubule walls. This DT occlusion method could achieve both mechanical resistance and acid resistance, demonstrating the potential of an inexpensive, long-term, and efficient therapy for treating DH.


Asunto(s)
Biomimética , Dentina , Microscopía Electrónica de Rastreo , Minerales
6.
PLoS One ; 10(4): e0120151, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25915744

RESUMEN

This paper intends to generate the approximate Voronoi diagram in the geodesic metric for some unbiased samples selected from original points. The mesh model of seeds is then constructed on basis of the Voronoi diagram. Rather than constructing the Voronoi diagram for all original points, the proposed strategy is to run around the obstacle that the geodesic distances among neighboring points are sensitive to nearest neighbor definition. It is obvious that the reconstructed model is the level of detail of original points. Hence, our main motivation is to deal with the redundant scattered points. In implementation, Poisson disk sampling is taken to select seeds and helps to produce the Voronoi diagram. Adaptive reconstructions can be achieved by slightly changing the uniform strategy in selecting seeds. Behaviors of this method are investigated and accuracy evaluations are done. Experimental results show the proposed method is reliable and effective.


Asunto(s)
Algoritmos , Huesos/anatomía & histología , Procesamiento de Imagen Asistido por Computador/estadística & datos numéricos , Modelos Anatómicos , Animales , Simulación por Computador , Mano/anatomía & histología , Humanos , Modelos Logísticos , Conejos
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