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1.
Small ; 20(21): e2307981, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38126913

RESUMEN

A new method to engineer hierarchically porous zeolitic imidazolate frameworks (ZIFs) through selective ligand removal (SeLiRe) is presented. This innovative approach involves crafting mixed-ligand ZIFs (ML-ZIFs) with varying proportions of 2-aminobenzimidazole (NH2-bIm) and 2-methylimidazole (2-mIm), followed by controlled thermal treatments. This process creates a dual-pore system, incorporating both micropores and additional mesopores, suggesting selective cleavage of metal-ligand coordination bonds. Achieving this delicate balance requires adjustment of heating conditions for each mixed-ligand ratio, enabling the targeted removal of NH2-bIm from a variety of ML-ZIFs while preserving their inherent microporous framework. Furthermore, the distribution of the initial thermolabile ligand plays a pivotal role in determining the resulting mesopore architecture. The efficacy of this methodology is aptly demonstrated through the assessment of hierarchically porous ZIFs for their potential in adsorbing diverse organic dyes in aqueous environments. Particularly striking is the performance of the 10%NH2-ZIF-2 h, which showcases an astonishing 40-fold increase in methylene blue adsorption capacity compared to ZIF-8, attributed to larger pore volumes that accelerate the diffusion of dye molecules to adsorption sites. This versatile technique opens new avenues for designing micro/mesoporous ZIFs, particularly suited for liquid media scenarios necessitating efficient active site access and optimal diffusion kinetics, such as purification, catalysis, and sensing.

2.
Inorg Chem ; 61(24): 9318-9327, 2022 Jun 20.
Artículo en Inglés | MEDLINE | ID: mdl-35675572

RESUMEN

Rational design and fabrication of efficient and low-cost catalysts for both the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are crucial for hydrogen production from water electrolysis. Herein, we report heteroatom Fe-incorporated Ni5P4 (Fe-NiP) as an excellent bifunctional catalyst for overall water splitting. Density functional theory (DFT) calculations reveal that heteroatom Fe effectively steers the electronic structure of Ni5P4, which optimizes the hydrogen adsorption behavior. Additionally, the hierarchical conductive framework of Fe-NiP contributes to abundant active sites. Thus, the Fe-NiP catalyst shows robust performance with enhanced intrinsic catalytic activity. As a good bifunctional catalyst, it demands low overpotentials of 144 and 223 mV to deliver a current density of 10 mA cm-2 for HER and OER, respectively. Considering the good bifunctional activity, an outstanding electrolyzer has been successfully assembled, which is superior to the benchmark of a RuO2(+)//Pt/C(-) electrolyzer. This study sheds light on steering the electronic structure of electrocatalysts through a heteroatom modulation strategy.

3.
Angew Chem Int Ed Engl ; 61(3): e202112116, 2022 Jan 17.
Artículo en Inglés | MEDLINE | ID: mdl-34704659

RESUMEN

The electrochemical reduction of CO2 to hydrocarbons involves a multistep proton-coupled electron transfer (PCET) reaction. Second coordination sphere engineering is reported to be effective in the PCET process; however, little is known about the actual catalytic active sites under realistic operating conditions. We have designed a defect-containing metal-organic framework, HKUST-1, through a facile "atomized trimesic acid" strategy, in which Cu atoms are modified by unsaturated carboxylate ligands, producing coordinatively unsaturated Cu paddle wheel (CU-CPW) clusters. We investigate the dynamic behavior of the CU-CPW during electrochemical reconstruction through the comprehensive analysis of in situ characterization results. It is demonstrated that Cu2 (HCOO)3 is maintained after electrochemical reconstruction and that is behaves as an active site. Mechanistic studies reveal that CU-CPW accelerates the proton-coupled multi-electron transfer (PCMET) reaction, resulting in a deep CO2 reduction reaction.

4.
Clin Lab ; 61(11): 1589-99, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-26731982

RESUMEN

Tumor biomarkers can serve as tools for early detection, diagnosis, prognosis, therapeutic target, response predicting, therapy monitoring of tumors or can be used as surrogate endpoints. Their abilities to assist various clinical decisions make them indispensable tools for current oncotherapies. Therefore, in the past decades, significant effort has been put into finding sensitive, specific, noninvasive, inexpensive, and clinically feasible tumor biomarkers. This review will summarize the recent progress made in different kinds of tumor biomarkers, introduce a promising and versatile novel tumor biomarker called DEK oncoprotein, and lastly, discuss the prospects of tumor biomarkers.


Asunto(s)
Biomarcadores de Tumor/análisis , Neoplasias/diagnóstico , Biomarcadores de Tumor/sangre , Biomarcadores de Tumor/orina , Humanos , Neoplasias/química
5.
Front Psychol ; 13: 939426, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35859822

RESUMEN

This study implies finding the linkages among financial inclusion, non-performing loans (NPLs), and economic growth. The study uses large panel data of 21 Organization for Economic Corporation and Development (OECD) countries for the dynamic panel estimation by using the Driscoll-Kraay standard errors with fixed effect. The results of the dynamic panel estimation technique revealed the existence of a long-run relationship among financial inclusion, NPLs, and economic growth. Financial inclusion contributes positively to economic growth by reducing NPLs. Furthermore, NPLs negatively impact financial inclusion as well as economic growth. The study presents important policy recommendations to control NPLs and boost the level of financial inclusion in the selected economies.

6.
Adv Mater ; 34(21): e2201774, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35363922

RESUMEN

Achieving efficient and durable nonprecious hydrogen evolution reaction (HER) catalysts for scaling up alkaline water/seawater electrolysis is desirable but remains a significant challenge. Here, a heterogeneous Ni-MoN catalyst consisting of Ni and MoN nanoparticles on amorphous MoN nanorods that can sustain large-current-density HER with outstanding performance is demonstrated. The hierarchical nanorod-nanoparticle structure, along with a large surface area and multidimensional boundaries/defects endows the catalyst with abundant active sites. The hydrophilic surface helps to achieve accelerated gas-release capabilities and is effective in preventing catalyst degradation during water electrolysis. Theoretical calculations further prove that the combination of Ni and MoN effectively modulates the electron redistribution at their interface and promotes the sluggish water-dissociation kinetics at the Mo sites. Consequently, this Ni-MoN catalyst requires low overpotentials of 61 and 136 mV to drive current densities of 100 and 1000 mA cm-2 , respectively, in 1 m KOH and remains stable during operation for 200 h at a constant current density of 100 or 500 mA cm-2 . This good HER catalyst also works well in alkaline seawater electrolyte and shows outstanding performance toward overall seawater electrolysis with ultralow cell voltages.

7.
Oncol Lett ; 15(6): 8573-8581, 2018 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-29844811

RESUMEN

DEK is a protein ubiquitously expressed in multicellular organisms as well as certain unicellular organisms. It is associated with the regulation of cell proliferation, differentiation, migration, apoptosis, senescence, self-renewal and DNA repairing. In tumor cells it is associated with the carcinogenesis process, however there have been few previous studies into the expression of DEK in lung cancer. In the present study the expression level of DEK mRNA and protein was detected in lung cancer tissues and non-cancerous counterparts by performing reverse transcription-quantitative polymerase chain reaction and immunohistochemical staining. It was revealed that the expression of DEK was increased in lung cancer tissues compared with normal tissue. Knock-down and over-expression of DEK in A549 cells were performed to determine the role of DEK in tumor formation. An MTT assay, colony formation assay and Matrigel invasion assay demonstrated that DEK positively regulated cell proliferation and invasion. These results suggest that DEK is highly expressed in lung cancer tissues and positively regulates cell proliferation and invasion.

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