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1.
J Am Chem Soc ; 146(33): 23278-23288, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39049154

RESUMO

Manipulating electronic polarizations such as ferroelectric or spin polarizations has recently emerged as an effective strategy for enhancing the efficiency of photocatalytic reactions. This study demonstrates the control of electronic polarizations modulated by ferroelectric and magnetic approaches within a two-dimensional (2D) layered crystal of copper indium thiophosphate (CuInP2S6) to boost the photocatalytic reduction of CO2. We investigate the substantial influence of ferroelectric polarization on the photocatalytic CO2 reduction efficiency, utilizing the ferroelectric-paraelectric phase transition and polarization alignment through electrical poling. Additionally, we explore enhancing the CO2 reduction efficiency by harnessing spin electrons through the synergistic introduction of sulfur vacancies and applying a magnetic field. Several advanced characterization techniques, including piezoresponse force microscopy, ultrafast pump-probe spectroscopy, in situ X-ray absorption spectroscopy, and in situ diffuse reflectance infrared Fourier transformed spectroscopy, are performed to unveil the underlying mechanism of the enhanced photocatalytic CO2 reduction. These findings pave the way for manipulating electronic polarizations regulated through ferroelectric or magnetic modulations in 2D layered materials to advance the efficiency of photocatalytic CO2 reduction.

2.
Curr Med Sci ; 44(2): 406-418, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38619681

RESUMO

OBJECTIVE: Uterine corpus endometrial carcinoma (UCEC), a kind of gynecologic malignancy, poses a significant risk to women's health. The precise mechanism underlying the development of UCEC remains elusive. Zinc finger protein 554 (ZNF554), a member of the Krüppel-associated box domain zinc finger protein superfamily, was reported to be dysregulated in various illnesses, including malignant tumors. This study aimed to examine the involvement of ZNF554 in the development of UCEC. METHODS: The expression of ZNF554 in UCEC tissues and cell lines were examined by qRT-PCR and Western blot assay. Cells with stably overexpressed or knocked-down ZNF554 were established through lentivirus infection. CCK-8, wound healing, and Transwell invasion assays were employed to assess cell proliferation, migration, and invasion. Propidium iodide (PI) staining combined with fluorescence-activated cell sorting (FACS) flow cytometer was utilized to detect cell cycle distribution. qRT-PCR and Western blotting were conducted to examine relative mRNA and protein levels. Chromatin immunoprecipitation assay and luciferase reporter assay were used to explore the regulatory role of ZNF554 in RNA binding motif 5 (RBM5). RESULTS: The expression of ZNF554 was found to be reduced in both UCEC samples and cell lines. Decreased expression of ZNF554 was associated with higher tumor stage, decreased overall survival, and reduced disease-free survival in UCEC. ZNF554 overexpression suppressed cell proliferation, migration, and invasion, while also inducing cell cycle arrest. In contrast, a decrease in ZNF554 expression resulted in the opposite effect. Mechanistically, ZNF554 transcriptionally regulated RBM5, leading to the deactivation of the Wingless (WNT)/ß-catenin signaling pathway. Moreover, the findings from rescue studies demonstrated that the inhibition of RBM5 negated the impact of ZNF554 overexpression on ß-catenin and p-glycogen synthase kinase-3ß (p-GSK-3ß). Similarly, the deliberate activation of RBM5 reduced the increase in ß-catenin and p-GSK-3ß caused by the suppression of ZNF554. In vitro experiments showed that ZNF554 overexpression-induced decreases in cell proliferation and migration were counteracted by RBM5 knockdown. Additionally, when RBM5 was overexpressed, it hindered the improvements in cell proliferation and migration caused by reducing the ZNF554 levels. CONCLUSION: ZNF554 functions as a tumor suppressor in UCEC. Furthermore, ZNF554 regulates UCEC progression through the RBM5/WNT/ß-catenin signaling pathway. ZNF554 shows a promise as both a prognostic biomarker and a therapeutic target for UCEC.


Assuntos
Neoplasias do Endométrio , Via de Sinalização Wnt , Feminino , Humanos , beta Catenina/genética , beta Catenina/metabolismo , Proteínas de Ciclo Celular/genética , Linhagem Celular Tumoral , Proteínas de Ligação a DNA/genética , Neoplasias do Endométrio/genética , Glicogênio Sintase Quinase 3 beta/metabolismo , Proteínas de Ligação a RNA/metabolismo , Proteínas Supressoras de Tumor/genética , Via de Sinalização Wnt/genética
3.
Small ; : e2400724, 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38639018

RESUMO

The lack of intrinsic active sites for photocatalytic CO2 reduction reaction (CO2RR) and fast recombination rate of charge carriers are the main obstacles to achieving high photocatalytic activity. In this work, a novel phosphorus and boron binary-doped graphitic carbon nitride, highly porous material that exhibits powerful photocatalytic CO2 reduction activity, specifically toward selective CO generation, is disclosed. The coexistence of Lewis-acidic and Lewis-basic sites plays a key role in tuning the electronic structure, promoting charge distribution, extending light-harvesting ability, and promoting dissociation of excitons into active carriers. Porosity and dual dopants create local chemical environments that activate the pyridinic nitrogen atom between the phosphorus and boron atoms on the exposed surface, enabling it to function as an active site for CO2RR. The P-N-B triad is found to lower the activation barrier for reduction of CO2 by stabilizing the COOH reaction intermediate and altering the rate-determining step. As a result, CO yield increased to 22.45 µmol g-1 h-1 under visible light irradiation, which is ≈12 times larger than that of pristine graphitic carbon nitride. This study provides insights into the mechanism of charge carrier dynamics and active site determination, contributing to the understanding of the photocatalytic CO2RR mechanism.

4.
Small Methods ; : e2301674, 2024 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-38284329

RESUMO

Double-atom site catalysts (DASs) have emerged as a recent trend in the oxygen reduction reaction (ORR), thereby modifying the intermediate adsorption energies and increasing the activity. However, the lack of an efficient dual atom site to improve activity and durability has limited these catalysts from widespread application. Herein, the nitrogen-coordinated iron and tin-based DASs (Fe-Sn-N/C) catalyst are synthesized for ORR. This catalyst has a high activity with ORR half-wave potentials (E1/2 ) of 0.92 V in alkaline, which is higher than those of the state-of-the-art Pt/C (E1/2  = 0.83 V), Fe-N/C (E1/2  = 0.83 V), and Sn-N/C (E1/2  = 0.77 V). Scanning electron transmission microscopy analysis confirmed the atomically distributed Fe and Sn sites on the N-doped carbon network. X-ray absorption spectroscopy analysis revealed the charge transfer between Fe and Sn. Both experimental and theoretical results indicate that the Sn with Fe-NC (Fe-Sn-N/C) induces charge redistribution, weakening the binding strength of oxygenated intermediates and leading to improved ORR activity. This study provides the synergistic effects of DASs catalysts and addresses the impacts of P-block elements on d-block transition metals in ORR.

5.
Small Methods ; 7(10): e2300348, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37350490

RESUMO

Basic insight into the structural evolution of electrocatalysts under operating conditions is of substantial importance for designing water oxidation catalysts. The first-row transition metal-based catalysts present state-of-the-art oxygen evolution reaction (OER) performance under alkaline conditions. Apparently, confinement has become an exciting strategy to boost the performance of these catalysts. The van der Waals (vdW) gaps of transition metal dichalcogenides are acknowledged to serve as a suitable platform to confine the first-row transition metal catalysts. This study focuses on confining Ni(OH)2 nanoparticle in the vdW gaps of 2D exfoliated SnS2 (Ex-SnS2 ) to accelerate water oxidation and to guarantee long term durability in alkaline solutions. The trends in oxidation states of Ni are probed during OER catalysis. The in situ studies confirm that the confined system produces a favorable environment for accelerated oxygen gas evolution, whereas the un-confined system proceeds with a relatively slower kinetics. The outstanding OER activity and excellent stability, with an overpotential of 300 mV at 100 mA cm-2 and Tafel slope as low as 93 mV dec-1 results from the confinement effect. This study sheds light on the OER mechanism of confined catalysis and opens up a way to develop efficient and low-cost electrocatalysts.

6.
Zhongguo Zhong Yao Za Zhi ; 48(10): 2620-2624, 2023 May.
Artigo em Chinês | MEDLINE | ID: mdl-37282922

RESUMO

Chaihu Jia Longgu Muli Decoction was firstly recorded in Treatise on Cold Damage(ZHANG Zhong-jing, Eastern Han dynasty). According to this medical classic, it is originally used in the treatment of the Shaoyang and Yangming syndrome. Based on the modern pathophysiological mechanism, this study interpreted the classic provisions of Chaihu Jia Longgu Muli Decoction. Original records of "chest fullness" "annoyance" "shock" "difficult urination" "delirium" "heavy body and failing to turn over" all have profound pathophysiological basis, involving disorders in cardiovascular, respiratory, nervous, and mental systems. This formula is widely used, which can be applied to treat epilepsy, cerebral arteriosclerosis, cerebral infarction, and other cerebrovascular diseases, hypertension, arrhythmia, and other cardiovascular diseases, insomnia, constipation, anxiety, depression, cardiac neurosis and other acute and chronic diseases as well as diseases in psychosomatic medicine. The clinical indications include Bupleuri Radix-targeted syndrome such as fullness and discomfort in chest and hypochondrium, bitter taste mouth, dry throat, and dizziness, the insomnia, anxiety, depression, susceptibility to fright, upset, dreamfulness and other psychiatric symptoms, red tongue, thick and yellow tongue coating, and wiry hard and powerful pulse. This formula was found to be used in combination with other formulas, such as Gualou Xiebai Decoction, Wendan Decoction, Zhizhu Pills, Juzhijiang Decoction, Suanzaoren Decoction, and Banxia Baizhu Tianma Decoction.


Assuntos
Medicamentos de Ervas Chinesas , Hipertensão , Distúrbios do Início e da Manutenção do Sono , Humanos , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Hipertensão/tratamento farmacológico , Síndrome , Arritmias Cardíacas/tratamento farmacológico , Medicina Tradicional Chinesa
7.
Commun Chem ; 6(1): 118, 2023 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-37301865

RESUMO

Structural flexibility is a critical issue that limits the application of metal-organic framework (MOF) membranes for gas separation. Herein we propose a mixed-linker approach to suppress the structural flexibility of the CAU-10-based (CAU = Christian-Albrechts-University) membranes. Specifically, pure CAU-10-PDC membranes display high separation performance but at the same time are highly unstable for the separation of CO2/CH4. A partial substitution (30 mol.%) of the linker PDC with BDC significantly improves its stability. Such an approach also allows for decreasing the aperture size of MOFs. The optimized CAU-10-PDC-H (70/30) membrane possesses a high separation performance for CO2/CH4 (separation factor of 74.2 and CO2 permeability of 1,111.1 Barrer under 2 bar of feed pressure at 35°C). A combination of in situ characterization with X-ray diffraction (XRD) and diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy, as well as periodic density functional theory (DFT) calculations, unveils the origin of the mixed-linker approach to enhancing the structural stability of the mixed-linker CAU-10-based membranes during the gas permeation tests.

8.
J Am Chem Soc ; 145(14): 7829-7836, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-37010254

RESUMO

Acidic water electrolysis enables the production of hydrogen for use as a chemical and as a fuel. The acidic environment hinders water electrolysis on non-noble catalysts, a result of the sluggish kinetics associated with the adsorbate evolution mechanism, reliant as it is on four concerted proton-electron transfer steps. Enabling a faster mechanism with non-noble catalysts will help to further advance acidic water electrolysis. Here, we report evidence that doping Ba cations into a Co3O4 framework to form Co3-xBaxO4 promotes the oxide path mechanism and simultaneously improves activity in acidic electrolytes. Co3-xBaxO4 catalysts reported herein exhibit an overpotential of 278 mV at 10 mA/cm2 in 0.5 M H2SO4 electrolyte and are stable over 110 h of continuous water oxidation operation. We find that the incorporation of Ba cations shortens the Co-Co distance and promotes OH adsorption, findings we link to improved water oxidation in acidic electrolyte.

9.
J Am Chem Soc ; 145(11): 6087-6099, 2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36853653

RESUMO

Efficient O2 reduction reaction (ORR) for selective H2O generation enables advanced fuel cell technology. Nonprecious metal catalysts are viable and attractive alternatives to state-of-the-art Pt-based materials that are expensive. Cu complexes inspired by Cu-containing O2 reduction enzymes in nature are yet to reach their desired ORR catalytic performance. Here, the concept of mechanical interlocking is introduced to the ligand architecture to enforce dynamic spatial restriction on the Cu coordination site. Interlocked catenane ligands could govern O2 binding mode, promote electron transfer, and facilitate product elimination. Our results show that ligand interlocking as a catenane steers the ORR selectivity to H2O as the major product via the 4e- pathway, rivaling the selectivity of Pt, and boosts the onset potential by 130 mV, the mass activity by 1.8 times, and the turnover frequency by 1.5 fold as compared to the noninterlocked counterpart. Our Cu catenane complex represents one of the first examples to take advantage of mechanical interlocking to afford electrocatalysts with enhanced activity and selectivity. The mechanistic insights gained through this integrated experimental and theoretical study are envisioned to be valuable not just to the area of ORR energy catalysis but also with broad implications on interlocked metal complexes that are of critical importance to the general fields in redox reactions involving proton-coupled electron transfer steps.

10.
J Dent Sci ; 18(1): 264-271, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36643279

RESUMO

Background/purpose: Limited studies have discussed the convergent profiles regarding tapered implants based on biological considerations. This study analyzed the convergent angles (CAs) of premolar roots and imitated a tapered implant according to the anatomy of tooth roots. Materials and methods: A total of 60 single-rooted premolars were explored by micro-computed tomography. Every individual root was divided into 10 segments corono-apically, and the roots' buccolingual (BL) and mesiodistal (MD) CAs were measured by sections. To mimic a dental implant, the irregular shape of examined root cross-sections was transformed into a circular shape with equal areas. A biomimetic dental implant (BDI) was reconstructed and its CAs were compared with those of the natural roots' BL and MD at the examined levels and overall estimation. Results: In general, the maxillary and mandibular premolars demonstrated comparable CA patterns. However, significantly different CA patterns of BL, MD, and BDI were developed for both the maxillary and mandibular roots at the examined levels. The BL's CAs were greater than those CAs measured from the BDI and MD aspects, particularly for the sections at the middle and apical thirds of the roots. For overall CAs, the BDI's CAs were comparable with the average CAs of the BL and MD for both premolar groups. Conclusion: Instead of a cylindrical configuration, the BDI prototype demonstrated a tapered model with a continuous slope. The average CA of BDI was 14°-24°, serving as a biological reference for future tapered implant design and research.

11.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-1009828

RESUMO

OBJECTIVES@#To improve the understanding of the clinical phenotypes and genetic characteristics of nephronophthisis (NPHP) and related syndromes in children.@*METHODS@#A retrospective analysis was performed on the medical data of eight children with NPHP and related syndromes who were diagnosed and treated in the Department of Pediatrics of the Second Hospital of Hebei Medical University, from January 2018 to November 2022. The clinical characteristics and genetic testing results were analyzed.@*RESULTS@#Among these eight children, there were five boys and three girls, with an age of onset ranging from 15 months to 12 years. All 8 children exhibited different degrees of renal function abnormalities when they attended the hospital. Among the eight children, two had the initial symptom of delayed development, two had the initial symptom of anemia, and two were found to have abnormal renal function during physical examination. The extrarenal manifestations included cardiovascular abnormalities in two children, skeletal dysplasia in two children, liver dysfunction in one child, retinitis pigmentosa in one child, and visceral translocation in one child. All eight children had renal structural changes on ultrasound, and four children had mild to moderate proteinuria based on routine urine test. Of all eight children, five had NPHP1 gene mutations and one each had a gene mutation in the NPHP3, IFT140, and TTC21B genes, and four new mutation sites were discovered.@*CONCLUSIONS@#Children with NPHP and related syndromes often have the initial symptom of delayed development or anemia, and some children also have extrarenal manifestations. NPHP and related syndromes should be considered for children with unexplained renal dysfunction, and high-throughput sequencing may help to make a confirmed diagnosis.


Assuntos
Criança , Humanos , Estudos Retrospectivos , Síndrome , Doenças Renais Císticas/genética , Mutação , Fenótipo
12.
Artigo em Chinês | WPRIM (Pacífico Ocidental) | ID: wpr-981365

RESUMO

Chaihu Jia Longgu Muli Decoction was firstly recorded in Treatise on Cold Damage(ZHANG Zhong-jing, Eastern Han dynasty). According to this medical classic, it is originally used in the treatment of the Shaoyang and Yangming syndrome. Based on the modern pathophysiological mechanism, this study interpreted the classic provisions of Chaihu Jia Longgu Muli Decoction. Original records of "chest fullness" "annoyance" "shock" "difficult urination" "delirium" "heavy body and failing to turn over" all have profound pathophysiological basis, involving disorders in cardiovascular, respiratory, nervous, and mental systems. This formula is widely used, which can be applied to treat epilepsy, cerebral arteriosclerosis, cerebral infarction, and other cerebrovascular diseases, hypertension, arrhythmia, and other cardiovascular diseases, insomnia, constipation, anxiety, depression, cardiac neurosis and other acute and chronic diseases as well as diseases in psychosomatic medicine. The clinical indications include Bupleuri Radix-targeted syndrome such as fullness and discomfort in chest and hypochondrium, bitter taste mouth, dry throat, and dizziness, the insomnia, anxiety, depression, susceptibility to fright, upset, dreamfulness and other psychiatric symptoms, red tongue, thick and yellow tongue coating, and wiry hard and powerful pulse. This formula was found to be used in combination with other formulas, such as Gualou Xiebai Decoction, Wendan Decoction, Zhizhu Pills, Juzhijiang Decoction, Suanzaoren Decoction, and Banxia Baizhu Tianma Decoction.


Assuntos
Humanos , Distúrbios do Início e da Manutenção do Sono/tratamento farmacológico , Medicamentos de Ervas Chinesas/uso terapêutico , Hipertensão/tratamento farmacológico , Síndrome , Arritmias Cardíacas/tratamento farmacológico , Medicina Tradicional Chinesa
13.
ACS Nano ; 16(8): 12202-12213, 2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-35959924

RESUMO

Net-zero carbon strategies and green synthesis methodologies are key to realizing the United Nations' sustainable development goals (SDGs) on a global scale. An electrocatalytic glycerol oxidation reaction (GOR) holds the promise of upcycling excess glycerol from biodiesel production directly into precious hydrocarbon commodities that are worth orders of magnitude more than the glycerol feedstock. Despite years of research on the GOR, the synthesis process of nanoscale electrocatalysts still involves (1) prohibitive heat input, (2) expensive vacuum chambers, and (3) emission of toxic liquid pollutants. In this paper, these knowledge gaps are closed via developing a laser-assisted nanomaterial preparation (LANP) process to fabricate bimetallic nanocatalysts (1) at room temperature, (2) under an ambient atmosphere, and (3) without liquid waste emission. Specifically, PdCu nanoparticles with adjustable Pd:Cu content supported on few-layer graphene can be prepared using this one-step LANP method with performance that can rival state-of-the-art GOR catalysts. Beyond exhibiting high GOR activity, the LANP-fabricated PdCu/C nanomaterials with an optimized Pd:Cu ratio further deliver an exclusive product selectivity of up to 99% for partially oxidized C3 products with value over 280000-folds that of glycerol. Through DFT calculations and in situ XAS experiments, the synergy between Pd and Cu is found to be responsible for the stability under GOR conditions and preference for C3 products of LANP PdCu. This dry LANP method is envisioned to afford sustainable production of multimetallic nanoparticles in a continuous fashion as efficient electrocatalysts for other redox reactions with intricate proton-coupled electron transfer steps that are central to the widespread deployment of renewable energy schemes and carbon-neutral technologies.

14.
Rapid Commun Mass Spectrom ; 36(18): e9351, 2022 Sep 30.
Artigo em Inglês | MEDLINE | ID: mdl-35802517

RESUMO

RATIONALE: Thermogravimetry (TG) combined with electrospray and atmospheric chemical ionization (ESI+APCI) mass spectrometry (MS) was developed to rapidly characterize thermal decomposition products of synthetic polymers and plastic products. The ESI-based TG-MS method is useful for characterizing thermally labile, nonvolatile, and polar compounds over an extensive mass range; and the APCI-based TG-MS counterpart is useful for characterizing volatile and nonpolar compounds. Both polar and nonpolar compounds can be simultaneously detected by ESI+APCI-based TG-MS. METHODS: Analytes with different volatility were produced from TG operated at different temperatures, which were delivered through a heated stainless-steel tube to the ESI+APCI source where they reacted with the primary charged species generated from electrospray and atmospheric pressure chemical ionization (ESI+APCI) of solvent and nitrogen. The analyte ions were then detected by an ion trap mass spectrometer. RESULTS: A semi-volatile PEG 600 standard was used as the sample and protonated and sodiated molecular ions together with adduct ions including [(PEG)n + 15]+ , [(PEG)n + 18]+ , and [(PEG)n + 29]+ were detected by TG-ESI+APCI-MS. The technique was further utilized to characterize thermal decomposition products of nonvolatile polypropylene glycol (PPG) and polystyrene (PS) standards, as well as a PS-made water cup and coffee cup lid. The characteristic fragments of PPG and PS with mass differences of 58 and 104 between respective ion peaks were detected at the maximum decomposition temperature (Tmax ). CONCLUSIONS: The information obtained from the TG-ESI+APCI-MS analysis is useful in rapidly distinguishing different types of polymers and their products. In addition, the signals of the additives in the polymer products, including antioxidants and plasticizers, were also detected before the TG temperature reached Tmax .


Assuntos
Pressão Atmosférica , Espectrometria de Massas por Ionização por Electrospray , Polímeros , Solventes , Espectrometria de Massas por Ionização por Electrospray/métodos , Termogravimetria
15.
Huan Jing Ke Xue ; 43(4): 1697-1705, 2022 Apr 08.
Artigo em Chinês | MEDLINE | ID: mdl-35393793

RESUMO

PM2.5 is the main component of haze, and Henan Province has become one of the key areas of PM2.5 pollution control. Based on the PM2.5 concentration data of Henan Province from 2015 to 2019, spatial autocorrelation, spatial hot spot detection, and other methods were used to analyze its temporal and spatial characteristics, and the geodetector method was introduced to analyze the interpretation strength of meteorological factors, air quality factors, and social factors on PM2.5 concentration. The results showed that:from 2015 to 2019, the concentration of PM2.5 in Henan Province showed an overall downward trend, the days of high pollution decreased, the days of low pollution increased, and the high pollution gradually transformed into medium pollution. The concentration of PM2.5 had obvious characteristics of spatial aggregation. The five-year global spatial autocorrelation index first dropped and then rose, and the spatial hot spots were concentrated in northern Henan (Anyang, Hebi, Xinxiang, and Jiaozuo); the spatial cold spots were concentrated in western Henan (Sanmenxia, Luoyang, and Nanyang). The shift in space center of gravity showed a trend of going north. Single-factor detection showed that among the nine influencing factors, land use type (0.511), precipitation (0.312), and NO2(0.277) were the most obvious factors affecting PM2.5 concentration, and the other factors were PM10(0.255), temperature (0.209), wind speed (0.183), O3(0.121), GDP(0.073), and population (0.046). Interaction detection showed that the combined effect of multiple factors was more significant than that of single factors. These results can provide theoretical support for the control of air pollution in Henan Province.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Poluição do Ar/análise , China , Monitoramento Ambiental/métodos , Conceitos Meteorológicos , Material Particulado/análise
16.
ACS Omega ; 7(11): 9152-9163, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35356688

RESUMO

The widespread use of energy storage technologies has created a high demand for the development of novel anode materials in Li-ion batteries (LIBs) with high areal capacity and faster electron-transfer kinetics. In this work, carbon-coated Cu2ZnSnS4 with a hierarchical 3D structure (CZTS@C) is used as an anode material for LIBs. The CZTS@C microstructures with enhanced electrical conductivity and improved Li-ion diffusivity exhibit high areal and gravimetric capacities of 2.45 mA h/cm2 and 1366 mA h/g, respectively. The areal capacity achieved in the present study is higher than that of previously reported CZTS-based materials. Moreover, in situ X-ray diffraction results show that lithium ions are stored in CZTS through the insertion reaction, followed by the alloying and conversion reactions at ∼1 V. The structural evolution of Li2S and Cu-Sn/Cu-Zn alloy phases occurs during the conversion and alloying reactions. The present work provides a cost-effective and simple method to prepare bulk CZTS and highlights the conformal carbon coating over CZTS, which can enhance the electrical and ionic conductivities of CZTS materials and increase the mass loading (1-2.3 mg/cm2). The improved stability and rate capability of CZTS@C anode materials can therefore be achieved.

17.
ACS Nano ; 16(3): 4298-4307, 2022 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-35254822

RESUMO

The adsorption and desorption of electrolyte ions strongly modulates the carrier density or carrier type on the surface of monolayer-MoS2 catalyst during the hydrogen evolution reaction (HER). The buildup of electrolyte ions onto the surface of monolayer MoS2 during the HER may also result in the formation of excitons and trions, similar to those observed in gate-controlled field-effect transistor devices. Using the distinct carrier relaxation dynamics of excitons and trions of monolayer MoS2 as sensitive descriptors, an in situ microcell-based scanning time-resolved liquid cell microscope is set up to simultaneously measure the bias-dependent exciton/trion dynamics and spatially map the catalytic activity of monolayer MoS2 during the HER. This operando probing technique used to monitor the interplay between exciton/trion dynamics and electrocatalytic activity for two-dimensional transition metal dichalcogenides provides an excellent platform to investigate the local carrier behaviors at the atomic layer/liquid electrolyte interfaces during electrocatalytic reaction.

18.
Nat Rev Chem ; 6(12): 862-880, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-37117701

RESUMO

Hybrid bilayer membrane (HBM) platforms represent an emerging nanoscale bio-inspired interface that has broad implications in energy catalysis and smart molecular devices. An HBM contains multiple modular components that include an underlying inorganic surface with a biological layer appended on top. The inorganic interface serves as a support with robust mechanical properties that can also be decorated with functional moieties, sensing units and catalytic active sites. The biological layer contains lipids and membrane-bound entities that facilitate or alter the activity and selectivity of the embedded functional motifs. With their structural complexity and functional flexibility, HBMs have been demonstrated to enhance catalytic turnover frequency and regulate product selectivity of the O2 and CO2 reduction reactions, which have applications in fuel cells and electrolysers. HBMs can also steer the mechanistic pathways of proton-coupled electron transfer (PCET) reactions of quinones and metal complexes by tuning electron and proton delivery rates. Beyond energy catalysis, HBMs have been equipped with enzyme mimics and membrane-bound redox agents to recapitulate natural energy transport chains. With channels and carriers incorporated, HBM sensors can quantify transmembrane events. This Review serves to summarize the major accomplishments achieved using HBMs in the past decade.


Assuntos
Prótons , Oxirredução , Transporte de Elétrons , Catálise
19.
Acta Pharmacol Sin ; 43(8): 2109-2118, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34876700

RESUMO

Cln Three Requiring 9 (CTR9), a scaffold protein of the polymerase-associated factor-1 (PAF1) complex (PAF1c), is primarily localized in the nucleus of cells. Recent studies show that CTR9 plays essential roles in the development of various human cancers and their occurrence; however, its regulatory roles and precise mechanisms in hepatocellular carcinoma (HCC) remain unclear. In this study, we investigated the roles of CTR9 using in vitro assays and a xenograft mouse model. We found that CTR9 protein is upregulated in tumor tissues from HCC patients. Knockdown of CTR9 substantially reduced HCC cell proliferation, invasion, and migration, whereas its overexpression promoted these activities. In addition, in vitro results revealed that CTR9 silencing dramatically increased cell cycle regulators, p21 and p27, but markedly decreased matrix metalloproteinases, MMP2 and MMP9, with these outcomes reversed upon CTR9 overexpression. Furthermore, the underlying molecular mechanism suggests that CTR9 promoted the oncogene paternally expressed gene 10 (PEG10) transcription via its promoter region. Finally, the oncogenic roles of CTR9 were confirmed in a xenograft mouse model. This study confirms that CTR9, an oncoprotein that promotes HCC cell proliferation, invasion, and migration, increases tumor growth in a xenograft mouse model. CTR9 could be a novel therapeutic target. Further investigation is warranted to verify CTR9 potential in novel therapies for HCC.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , Fosfoproteínas , Fatores de Transcrição , Animais , Proteínas Reguladoras de Apoptose/genética , Proteínas Reguladoras de Apoptose/metabolismo , Carcinogênese/genética , Carcinoma Hepatocelular/patologia , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células/genética , Proteínas de Ligação a DNA/genética , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/patologia , Camundongos , Fosfoproteínas/metabolismo , Proteínas de Ligação a RNA/metabolismo , Fatores de Transcrição/metabolismo
20.
J Prosthet Dent ; 128(6): 1320-1327, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33867165

RESUMO

STATEMENT OF PROBLEM: Developing tapered implants with the most appropriate angular characteristics requires an improved analysis of the anatomy of premolar roots. PURPOSE: The purpose of this observational study was to analyze the 3D anatomy of premolar roots by determining the tapered slope and convergent angle (TS/CA), to transform the TS/CA patterns into those in which the tapered implants mimic natural tooth roots, and to provide TS/CA references for future investigations. MATERIAL AND METHODS: A total of 73 human single-rooted premolars were surveyed and analyzed by microcomputed tomography and an associated software program. The 3D root surface area (RSA), the radius/diameter (R/D) at the planned first to tenth millimeter levels apical to the cementoenamel junction (CEJ), and the TS/CA at corresponding levels were calculated. The results were statistically analyzed by using an independent samples t test to assess the general differences of tested parameters between maxillary and mandibular premolars. A paired t test was used to examine the significant intragroup TS/CA differences between sequential coronoapical levels. One-way ANOVA was applied to study the general significance of developmental patterns in maxillary and/or mandibular groups. Two-way ANOVA was used to inspect the TS/CA significance at various measurements coronoapically between the maxillary and mandibular premolars (α=.05). RESULTS: Generally, the RSA, root length, R/D, and TS/CA parameters examined for the maxillary premolar roots differed significantly from those for the mandibular roots at the evaluated levels (P<.05). According to the measurements, the maxillary premolar roots generally exhibited nonsignificant RSA and R/D reduction patterns, with a decreasing angle of TS=13.44 degrees and CA=24.53 degrees coronoapically. However, mandibular premolar roots exhibited a significant reduction pattern, with TS=11.25 degrees and CA=21.06 degrees coronoapically according to both individual and general evaluations. CONCLUSIONS: Based on the developmental patterns of the evaluated TSs/CAs, tapered implants imitating premolar root anatomy should have a conical rather than a cylindrical shape, and the R/D of these models should be reduced to half at the apical third. However, further studies are warranted to identify more TS/CA characteristics related to the tapered implants, including the TSs/CAs of other tooth types.


Assuntos
Tomografia Computadorizada de Feixe Cônico , Implantes Dentários , Humanos , Dente Pré-Molar/cirurgia , Microtomografia por Raio-X/métodos , Tomografia Computadorizada de Feixe Cônico/métodos , Raiz Dentária/diagnóstico por imagem
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