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1.
Kaohsiung J Med Sci ; 40(7): 650-659, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-38757734

RESUMEN

Colorectal cancer (CRC) is notable for its high mortality and high metastatic characteristics. The shear force generated by bloodstream provides mechanical signals regulating multiple responses of cells, including metastatic cancer cells, dispersing in blood vessels. We, therefore, studied the effect of shear flow on circulating CRC cells in the present study. The CRC cell line SW620 was subjected to shear flow of 12.5 dynes/cm2 for 1 and 2 h separately. Resulting elevated caspase-9 and -3 indicated that shear flow initiated the apoptosis of SW620. Enlarged cell size associated with a higher level of cyclin D1 was coincident with the flow cytometric results indicating that the cell cycle was arrested at the G1 phase. An elevated phosphor-eNOSS1177 increased the production of nitric oxide and led to reactive oxygen species-mediated oxidative stress. Shear flow also regulated epithelial-mesenchymal transition (EMT) by increasing E-cadherin and ZO-1 while decreasing Snail and Twist1. The migration and invasion of sheared SW620 were also substantially decreased. Further investigations showed that mitochondrial membrane potential was significantly decreased, whereas mitochondrial mass and ATP production were not changed. In addition to the shear flow of 12.5 dynes/cm2, the expressions of EMT were compared at lower (6.25 dynes/cm2) and at higher (25 dynes/cm2) shear flow. The results showed that lower shear flow increased mesenchymal characteristics and higher shear flow increased epithelial characteristics. Shear flow reduces the malignancy of CRC in their metastatic dispersal that opens up new ways to improve cancer therapies by applying a mechanical shear flow device.


Asunto(s)
Apoptosis , Movimiento Celular , Neoplasias Colorrectales , Transición Epitelial-Mesenquimal , Especies Reactivas de Oxígeno , Humanos , Neoplasias Colorrectales/patología , Neoplasias Colorrectales/metabolismo , Línea Celular Tumoral , Especies Reactivas de Oxígeno/metabolismo , Estrés Mecánico , Potencial de la Membrana Mitocondrial , Ciclina D1/metabolismo , Estrés Oxidativo , Cadherinas/metabolismo , Óxido Nítrico/metabolismo , Caspasa 9/metabolismo , Caspasa 3/metabolismo , Proteína de la Zonula Occludens-1/metabolismo , Proteína 1 Relacionada con Twist/metabolismo
2.
Plants (Basel) ; 13(10)2024 May 16.
Artículo en Inglés | MEDLINE | ID: mdl-38794455

RESUMEN

Eggplant is a highly significant vegetable crop and extensively cultivated worldwide. Sepal color is considered one of the major commercial traits of eggplant. Eggplant sepals develop from petals, and sepals have the ability to change color by accumulating anthocyanins, but whether the eggplants in sepal and their biosynthetic pathways are the same as those in petals is not known. To date, little is known about the underlying mechanisms of sepal color formation. In this study, we performed bulked segregant analysis and transcriptome sequencing using eggplant sepals and obtained 1,452,898 SNPs and 182,543 InDel markers, respectively, as well as 123.65 Gb of clean data using transcriptome sequencing. Through marker screening, the genes regulating eggplant sepals were localized to an interval of 2.6 cM on chromosome 10 by bulked segregant analysis sequencing and transcriptome sequencing and co-analysis, combined with screening of molecular markers by capillary electrophoresis. Eight possible candidate genes were then screened to further interpret the regulatory incentives for the eggplant sepal color.

3.
medRxiv ; 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38766145

RESUMEN

Background: Multiple studies from countries with relatively lower PM 2.5 level demonstrated that acute and chronic exposure even at lower than recommended level, e.g., 9 µg/m 3 in the US increased the risk of cardiovascular (CV) events. However, limited studies using individual level data exist from countries with a wider range of PM levels to illustrate shape of the exposure-response curve throughout the range including > 20 µg/m 3 PM 2·5 concentrations. Taiwan with its policies reduced PM 2.5 over time provide opportunities to illustrate the dose response curves and how reductions of PM 2.5 over time correlated with CV events incidence in a nationwide sample. Methods: Using data from the 2009-2019 Taiwan National Health Insurance Database linked to nationwide PM2.5 data. We examined the shape and magnitude of the exposure-response curve between seasonal average PM 2·5 level and CV events-related hospitalizations among older adults at high-risk for CV events. We used history-adjusted marginal structural models including potential confounding by individual demographic factors, baseline comorbidities, and health service measures. To quantify the risk below and above 20 µg/m 3 we conducted stratified Cox regression. We also plotted PM 2.5 and CV events from 2009-2019 as well as average temperature as a comparison. Findings: Using the PM 2.5 concentration <15 µg/m 3 (Taiwan regulatory standard) as a reference, the seasonal average PM 2.5 concentration (15-23.5µg/m 3 and > 23.5 µg/m 3 ) were associated with hazard ration of 1.13 (95%CI 1.09-1.18) and 1.19 (95%CI 1.14-1.24), 1.07 (95%CI 1.03-1.11) and 1.14 (95%CI 1.10-1.18), 1.22 (95%CI 1.08-1.38) and 1.31 (95%CI 1.16-1.48), 1.04 (95%CI 0.98-1.10) and 1.10 (95%CI 1.04-1.16) respectively for HF, IS/TIA,PE/DVT and MI/ACS. A nonlinear relationship between PM 2·5 and CV events outcomes was observed at PM 2·5 levels above 20 µg/m 3 . Interpretation: A nonlinear exposure-response relationship between PM2·5 concentration and the incidence of cardiovascular events exists when PM2.5 is higher than the levels recommended by WHO Air Quality Guidelines. Further lowering PM2·5 levels beyond current regulatory standards may effectively reduce the incidence of cardiovascular events, particularly HF and DVT, and can lead to tangible health benefits in high-risk elderly population.

4.
J Phys Chem Lett ; 15(18): 4782-4791, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38663021

RESUMEN

Inorganic mixed-halogen perovskites exhibit excellent photovoltaic properties and stability; yet, their photoelectric conversion efficiency is limited by inherent surface defects. In this work, we study the impact of defects on properties of CsPbI2Br slabs using first-principles calculations, focusing on specific defects such as I vacancy (VI), I interposition (Ii), and I substitution by Pb (PbI). Our findings reveal that these defects affect the geometric and optoelectronic properties as well as dynamics of charge carriers of slabs. We employ two theoretical frameworks (surface hopping and Redfield theory) of nonadiabatic molecular dynamics simulations to comprehensively study relaxation processes and obtain consistent results. The presence of VI reduces carrier lifetimes, while the influence of PbI on carrier lifetimes is negligible. In contrast, Ii defects lead to prolonged carrier lifetimes. These insights provide valuable guidance for the rational design of perovskite photovoltaic devices, aiming to enhance their efficiency and stability.

5.
Biosci Biotechnol Biochem ; 88(5): 529-537, 2024 Apr 22.
Artículo en Inglés | MEDLINE | ID: mdl-38509025

RESUMEN

Four ethanol fractionated crude extracts (EFCEs [A-D]) purified from the leaves of Cinnamomum macrostemon Hayata were screened for antioxidative effects and mitochondrial function in HaCaT cells. The higher cell viability indicated that EFCE C was mildly toxic. Under the treatment of 50 ng/mL EFCE C, the hydrogen peroxide (H2O2)-induced cytosolic and mitochondrial reactive oxygen species levels were reduced as well as the H2O2-impaired cell viability, mitochondrial membrane potential (MMP), ATP production, and mitochondrial mass. The conversion of globular mitochondria to tubular mitochondria is coincident with EFCE C-restored mitochondrial function. The mitophagy activator rapamycin showed similar effects to EFCE C in recovering the H2O2-impaired cell viability, MMP, ATP production, mitochondrial mass, and also mitophagic proteins such as PINK1, Parkin, LC3 II, and biogenesis protein PGC-1α. We thereby propose the application of EFCE C in the prevention of oxidative stress in skin cells.


Asunto(s)
Supervivencia Celular , Cinnamomum , Peróxido de Hidrógeno , Queratinocitos , Potencial de la Membrana Mitocondrial , Mitocondrias , Mitofagia , Estrés Oxidativo , Extractos Vegetales , Especies Reactivas de Oxígeno , Humanos , Mitofagia/efectos de los fármacos , Queratinocitos/efectos de los fármacos , Queratinocitos/metabolismo , Queratinocitos/citología , Estrés Oxidativo/efectos de los fármacos , Extractos Vegetales/farmacología , Extractos Vegetales/química , Potencial de la Membrana Mitocondrial/efectos de los fármacos , Especies Reactivas de Oxígeno/metabolismo , Peróxido de Hidrógeno/metabolismo , Supervivencia Celular/efectos de los fármacos , Cinnamomum/química , Mitocondrias/efectos de los fármacos , Mitocondrias/metabolismo , Adenosina Trifosfato/metabolismo , Hojas de la Planta/química , Antioxidantes/farmacología , Ubiquitina-Proteína Ligasas/metabolismo , Sirolimus/farmacología , Células HaCaT , Proteínas Quinasas/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/genética
6.
Aging Clin Exp Res ; 36(1): 10, 2024 Jan 28.
Artículo en Inglés | MEDLINE | ID: mdl-38281223

RESUMEN

BACKGROUND: Circulating metabolites (CM) play a pivotal role in our overall health, yet the current evidence concerning the involvement of diverse CM in benign prostatic hyperplasia (BPH) remains limited. Mendelian randomization (MR) offers a promising avenue to explore the potential impact of CM on BPH. METHODS: In a forward MR analysis, a cohort of 249 circulating metabolites was employed as exposures to investigate their potential associations with BPH risk. Conversely, in a reverse MR analysis, BPH was employed as an exposure to assess its effects on CM. RESULTS: The forward MR analysis discerned a linkage between six metabolites and BPH, with careful consideration to excluding heterogeneity and pleiotropy. Subsequently, the reverse MR analysis unveiled that nine metabolic compounds, mainly comprising phospholipids and triglycerides, potentially exhibit elevated levels in BPH patients. CONCLUSION: Bidirectional MR analysis furnishes genetic insight into the interplay between CM and BPH. The prominence of lipids and triglycerides emerges as significant factors intricately linked to BPH risk.


Asunto(s)
Hiperplasia Prostática , Masculino , Humanos , Hiperplasia Prostática/genética , Hiperplasia , Análisis de la Aleatorización Mendeliana , Próstata , Triglicéridos
7.
Diabetes Care ; 47(2): 233-238, 2024 Feb 01.
Artículo en Inglés | MEDLINE | ID: mdl-38060348

RESUMEN

OBJECTIVE: To measure the association between ambient heat and hypoglycemia-related emergency department visit or hospitalization in insulin users. RESEARCH DESIGN AND METHODS: We identified cases of serious hypoglycemia among adults using insulin aged ≥65 in the U.S. (via Medicare Part A/B/D-eligible beneficiaries) and Taiwan (via National Health Insurance Database) from June to September, 2016-2019. We then estimated odds of hypoglycemia by heat index (HI) percentile categories using conditional logistic regression with a time-stratified case-crossover design. RESULTS: Among ∼2 million insulin users in the U.S. (32,461 hypoglycemia case subjects), odds ratios of hypoglycemia for HI >99th, 95-98th, 85-94th, and 75-84th percentiles compared with the 25-74th percentile were 1.38 (95% CI, 1.28-1.48), 1.14 (1.08-1.20), 1.12 (1.08-1.17), and 1.09 (1.04-1.13) respectively. Overall patterns of associations were similar for insulin users in the Taiwan sample (∼283,000 insulin users, 10,162 hypoglycemia case subjects). CONCLUSIONS: In two national samples of older insulin users, higher ambient temperature was associated with increased hypoglycemia risk.


Asunto(s)
Diabetes Mellitus , Hipoglucemia , Anciano , Humanos , Estados Unidos/epidemiología , Insulina/efectos adversos , Estudios Cruzados , Hipoglucemiantes , Calor , Taiwán/epidemiología , Estudios Retrospectivos , Medicare , Hipoglucemia/inducido químicamente , Hipoglucemia/epidemiología , Insulina Regular Humana
8.
Chemistry ; 30(9): e202302900, 2024 Feb 12.
Artículo en Inglés | MEDLINE | ID: mdl-38105290

RESUMEN

The catalytic mechanisms of nitrogen reduction reaction (NRR) on the pristine and Co/α-MoC(001) surfaces were explored by density functional theory calculations. The results show that the preferred pathway is that a direct N≡N cleavage occurs first, followed by continuous hydrogenations. The production of second NH3 molecule is identified as the rate-limiting step on both systems with kinetic barriers of 1.5 and 2.0 eV, respectively, indicating that N2 -to-NH3 transformation on bimetallic surface is more likely to occur. The two components of the bimetallic center play different roles during NRR process, in which Co atom does not directly participate in the binding of intermediates, but primarily serves as a reservoir of H atoms. This special synergy makes Co/α-MoC(001) have superior activity for ammonia synthesis. The introduction of Co not only facilitates N2 dissociation, but also accelerates the migration of H atom due to the antibonding characteristic of Co-H bond. This study offers a facile strategy for the rational design and development of efficient catalysts for ammonia synthesis and other reactions involving the hydrogenation processes.

9.
Front Plant Sci ; 14: 1210513, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37528971

RESUMEN

Solanum torvum (Swartz) (2n = 24) is a wild Solanaceae plant with high economic value that is used as a rootstock in grafting for Solanaceae plants to improve the resistance to a soil-borne disease caused by root-knot nematodes (RKNs). However, the lack of a high-quality reference genome of S. torvum hinders research on the genetic basis for disease resistance and application in horticulture. Herein, we present a chromosome-level assembly of genomic sequences for S. torvum combining PacBio long reads (HiFi reads), Illumina short reads and Hi-C scaffolding technology. The assembled genome size is ~1.25 Gb with a contig N50 and scaffold N50 of 38.65 Mb and 103.02 Mb, respectively as well as a BUSCO estimate of 98%. GO enrichment and KEGG pathway analysis of the unique S. torvum genes, including NLR and ABC transporters, revealed that they were involved in disease resistance processes. RNA-seq data also confirmed that 48 NLR genes were highly expressed in roots and fibrous roots and that three homologous NLR genes (Sto0288260.1, Sto0201960.1 and Sto0265490.1) in S. torvum were significantly upregulated after RKN infection. Two ABC transporters, ABCB9 and ABCB11 were identified as the hub genes in response to RKN infection. The chromosome-scale reference genome of the S. torvum will provide insights into RKN resistance.

10.
Dalton Trans ; 52(31): 10895-10904, 2023 Aug 08.
Artículo en Inglés | MEDLINE | ID: mdl-37489006

RESUMEN

Our density functional theory calculations show that silicon doping in g-CN (SiC3N3) can improve the electrochemical performance of g-CN as an anode of alkali metal-ion batteries and solve the problems of too high adsorption ability and migration energy barrier commonly found in porous carbon nitride. The stability of SiC3N3 was verified by molecular dynamics simulations and phonon spectroscopy. Elastic constant calculations revealed that the Si doping in g-CN can improve its mechanical properties. Specifically, Li/Na/K has a suitable adsorption capability (-0.71/-0.52/-0.98 eV) and a lower migration barrier (0.73/0.43/0.21 eV) on SiC3N3, where the barrier of a single Li-ion is the lowest among the doped porous carbon nitride materials studied so far. Moreover, SiC3N3 exhibits a high theoretical capacity (253/1512/1512 mA h g-1) and a low open-circuit voltage (0.48/0.18/0.31 V) for Li/Na/K ion batteries. Compared with B-doped g-CN previously studied, Si doping can more effectively improve the electronic conductivity of g-CN owing to greater charge transfer between Si and g-CN; the migration energy barrier of alkali metal ions on SiC3N3 is reduced more significantly due to its puckered structure instead of a planar structure; and the capacity of SiC3N3 is nearly doubled for alkali metal ion batteries because it has more feasible adsorption sites for alkali metals. These results suggest that Si-doped g-CN can be a universal anode material for alkali metal ion batteries.

11.
Chem Commun (Camb) ; 59(65): 9832-9835, 2023 Aug 10.
Artículo en Inglés | MEDLINE | ID: mdl-37505224

RESUMEN

Unlike traditional methods of modifying phthalocyanines (Pcs), we herein report a smart and visible way to switch the aromaticity of silicon(IV) phthalocyanines via a reversible nucleophilic addition reaction of the Pc skeleton induced by alkalis and acids, leading to an interesting allochroism phenomenon and the switching of photosensitive activities.

12.
ACS Omega ; 7(48): 43915-43922, 2022 Dec 06.
Artículo en Inglés | MEDLINE | ID: mdl-36506202

RESUMEN

The adsorptions of iron(II) phthalocyanine (FePc) on graphene and defective graphene were investigated systematically using density functional theory. Three types of graphene defects covering stone-wales (SW), single vacancy (SV), and double vacancy (DV) were taken into account, in which DV defects included DV(5-8-5), DV(555-777), and DV(5555-6-7777). The calculations of formation energies of defects showed that the SW defect has the lowest formation energy, and it was easier for DV defects to form compared with the SV defect. It is more difficult to rotate or move FePc on the surface of defective graphenes than on the surface of graphene due to bigger energy differences at different sites. Although the charge analysis indicated the charge transfers from graphene or defective graphene to FePc for all studied systems, the electron distributions of FePc on various defective graphenes were different. Especially for FePc@SV, the d xy orbital of Fe in the conduction band moved toward the Fermi level about 1 eV, and the d xz of Fe in the valence band for FePc@SV also moved toward the Fermi level compared with FePc@graphene and other FePc@defective graphenes. Between the planes of FePc and defective graphene, the electron accumulation occurs majorly in the position of the FePc molecular plane for FePc@SW, FePc@DV(5-8-5), and FePc@DV(5555-6-7777) as well as FePc@graphene. However, electrons were accumulated on the upper and lower surfaces of the FePc molecular plane for FePc@SV and FePc@DV(555-777). Thus, the electron distribution of FePc can be modulated by introducing the interfaces of different defective graphenes.

13.
Can Respir J ; 2022: 5460400, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36072643

RESUMEN

Objectives: Viral load is important when evaluating viral transmission potential, involving the use of a polymerase chain reaction (PCR) cycle threshold (Ct) value. We aimed to analyze the PCR Ct values of respiratory tract samples taken from patients with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) Omicron variant strains to evaluate these strains' viral dynamics. Methods: This study comprised 361 patients. The Ct values of SARS-CoV-2-related respiratory samples were compared between symptomatic and asymptomatic patients. Results: The median (25th percentile and 75th percentile) nasopharynx and oropharynx SARS-CoV-2 Ct values were 30.5 (24.5-35.0) and 34.5 (30.0-37.0) in the symptomatic group, respectively, and 27.8 (23.4-34.5) and 33.5 (26.0-35.0) in the asymptomatic group, respectively, without significance. In the symptomatic group, subgroup analyses according to age showed the mean nasal Ct value for patients aged >18 years was 29.0 (23.5-34.5), which was significantly lower than that of patients aged 0-4 years and 5-13 years (36.0 (30.5-38.0) and 34.5 (31.0-39.0), respectively). The nasal Ct value for asymptomatic patients aged >18 years was 25.5 (20.9-28.4), which was significantly lower than of patients aged 5-13 years (34.5 (25.6-36.4)). Conclusion: Our findings suggest that the viral loads of asymptomatic and symptomatic patients did not differ significantly. However, adults infected with SARS-CoV-2 had higher nasal viral loads that those of young children.


Asunto(s)
COVID-19 , ARN Viral , Adulto , Niño , Preescolar , Humanos , ARN Viral/análisis , SARS-CoV-2 , Carga Viral
14.
Vet Med Sci ; 8(6): 2532-2537, 2022 11.
Artículo en Inglés | MEDLINE | ID: mdl-36037318

RESUMEN

BACKGROUND: Herpesviruses are a class of double-stranded DNA viruses found in both vertebrates and invertebrates. They are usually highly host-specific and do not easily spread across species. Chinchillas have gradually entered the Chinese pet market in recent years, but references to viral infections in chinchillas are extremely scarce, and only two reports about the herpesvirus in chinchillas are available at present. OBJECTIVES: The aim of this study was to present the first report of FHV-1 infection in chinchillas. METHODS: A total of 130 nasopharyngeal swab samples of chinchillas and three nasopharyngeal swabs of domestic cats collected from a chinchillas farm were investigated by nested PCR for FHV-1. RESULTS: Four chinchillas were infected with FHV-1, the positive rate was 3.08% (4/130), and two domestic cats were FHV-1 positive (2/3). The 253 bp fragments of FHV-1 gD gene from four chinchillas and two domestic cats were 100% identical, respectively, and the homology between chinchillas and domestic cat was 99.21%, but they all shared nearly 98.81% homology with the reference strain sequences. Phylogenetic tree analysis showed that these four chinchillas strains were clustered together with FHV-1. CONCLUSIONS: This is the first time that FHV-1 was detected in chinchillas and suggested chinchillas are susceptible to FHV-1 and may play a role as a temporary reservoir for FHV-1.


Asunto(s)
Varicellovirus , Animales , Gatos , Chinchilla , Filogenia , Granjas
15.
Angew Chem Int Ed Engl ; 61(39): e202204561, 2022 Sep 26.
Artículo en Inglés | MEDLINE | ID: mdl-35931663

RESUMEN

Developing light-harvesting materials with broad spectral response is of fundamental importance in full-spectrum solar energy conversion. We found that, when a series of earth-abundant metal (Cu, Co, Ni and Fe) salts are dissolved in coordinating solvents uniformly dispersed nanodots (NDs) are formed rather than fully dissolving as molecular species. The previously unrecognized formation of this condensed state is ascribed to spontaneous aggregation of molecular transition-metal-complexes (TMCs) via weak intermolecular interactions, which results in redshifted and broadened absorption into the NIR region (200-1100 nm). Typical photoredox reactions, such as carbonylation and oxidative dehydrogenation, well demonstrate the feasibility of efficient utilization of NIR light (λ>780 nm) by TMCs NDs. Our finding provides a conceptually new strategy for extending the absorption towards low energy photons in solar energy harvesting and conversion via photoredox transformations.

16.
J Chem Phys ; 156(20): 204702, 2022 May 28.
Artículo en Inglés | MEDLINE | ID: mdl-35649874

RESUMEN

The properties of KTiOPO4Mx (M = K, Na, and Li; x = 0.000-1.000) as an anode for potassium-ion batteries (PIBs), sodium-ion batteries (SIBs), and lithium-ion batteries (LIBs) are investigated by density functional theory calculations. Our work reveals that the electrochemical performance of KTiOPO4 as an anode for PIBs is superior to that for SIBs and LIBs, in terms of average voltage and ion diffusion kinetics. The ab initio molecular dynamics simulations indicate that the KTiOPO4Mx anode exhibits high structural stability, and alkali ion intercalation contributes to accelerating ion diffusion during the charging process. Particularly, the low activation energy of 0.406 eV of K migration on surface KTP(210), obtained by the climbing-image nudged elastic band method, suggests a high-rate capability. The systematical comparison of the performance of KTiOPO4 as an anode for PIBs, SIBs, and LIBs on the theoretical perspective clarifies that a large channel is not always promising for small radius ion intercalation and diffusion.

17.
J Thorac Dis ; 14(5): 1411-1427, 2022 May.
Artículo en Inglés | MEDLINE | ID: mdl-35693591

RESUMEN

Background: With the advancement in machine learning (ML) and artificial neural networks as well as the development of portable electrocardiogram devices, artificial intelligence (AI) has been increasing in popularity over the years. In this study, we aimed to provide an overview of the research regarding the utilization of AI techniques to improve the diagnosis of arrhythmia. Methods: We extracted data published 2004 to 2021 from Web of Science database. The online analytic platform, Literature Metrology (http://bibliometric.com), was used to analyze publication trends, including information about journals, authors, institutions, collaborations between countries, citations, and keywords. Results: Keywords, such as deep learning, electrocardiogram (ECG), and convolutional neural network, have been increasing in frequency over the years. The analysis outcomes demonstrated that topics associated with AI, robotic prosthesis, and big data analysis for arrhythmia have become increasingly popular since 2016. Our study also found that atrial fibrillation (AF) and ventricular arrhythmia were the two ECG signal sharing the most interest. Conclusions: The utility of deep learning in diagnostics and the prognostication of arrhythmia has been gaining traction over the years, covering areas from electrocardiogram detection to atrial arrhythmogenesis model construction. Our study revealed the trend of topics from 2004 to 2021, which may help researchers to monitor future trends.

18.
Chemosphere ; 305: 135401, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-35738405

RESUMEN

To address the water pollution induced by pharmaceuticals, especially antibiotics, and pathogens, natural product emodin, a traditional Chinese medicine with the characteristic large π-conjugation anthraquinone structure, was used to rationally develop a novel Emodin/HAp photocatalyst by integrating with a thermally stable and recyclable support material hydroxyapatite (HAp) through a simple preparation method. It was found that its photocatalytic activity to generate reactive oxygen species (ROS) was greatly improved due to the migration of photogenerated electrons and holes between emodin and HAp upon visible light irradiation. Thus, this Emodin/HAp photocatalyst not only quickly photodegraded tetracycline with 99.0% removal efficiency but also exhibited complete photodisinfection of pathogenic bacteria Staphylococcus aureus upon visible light irradiation. Therefore, this study offers a new route for the design and preparation of multifunctional photocatalysts using widely available natural products for environmental remediation.


Asunto(s)
Productos Biológicos , Emodina , Antibacterianos/química , Antibacterianos/farmacología , Catálisis , Descontaminación , Durapatita , Luz , Tetraciclina
19.
ACS Appl Mater Interfaces ; 14(26): 29832-29843, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35735752

RESUMEN

In Li-excess transition metal-oxide cathode materials, anionic oxygen redox can offer high capacity and high voltages, although peroxo and superoxo species may cause oxygen loss, poor cycling performance, and capacity fading. Previous work showed that undesirable formation of peroxide and superoxide bonds was controlled to some extent by Mn substitution, and the present work uses density functional calculations to examine the reasons for this by studying the anionic redox mechanism in Li8MnO6. This material is obtained by substituting Mn for Sn in Li8SnO6 or for Zr in Li8ZrO6, and we also compare this to previous work on those materials. The calculations predict that Li8MnO6 is stable at room temperature (with a band gap of 3.19 eV as calculated by HSE06 and 1.82 eV as calculated with the less reliable PBE+U), and they elucidate the chemical and structural effects involved in the inhibition of oxygen release in this cathode. Throughout the whole delithiation process, only O2- ions are oxidized. The directional Mn-O bonds formed from unfilled 3d orbitals effectively inhibit the formation of O-O bonds, and the layered structure is maintained even after removing 3 Li per Li8MnO6 formula unit. The calculated average voltage for removal of 3 Li is 3.69 V by HSE06, and the corresponding capacity is 389 mAh/g. The high voltage of oxygen anionic redox and the high capacity result in a high energy density of 1436 Wh/kg. The Li-ion diffusion barrier for the dominant interlayer diffusion path along the c axis is 0.57 eV by PBE+U. These results help us to understand the oxygen redox mechanism in a new lithium-rich Li8MnO6 cathode material and contribute to the design of high-energy density lithium-ion battery cathode materials with favorable electrochemical properties based on anionic oxygen redox.

20.
Phys Chem Chem Phys ; 24(26): 16183-16192, 2022 Jul 06.
Artículo en Inglés | MEDLINE | ID: mdl-35749066

RESUMEN

First-principles calculations based on density functional theory were utilized to study the performance of Na2ZrO3 (NZO) and yttrium-doped Na2ZrO3 (Y-NZO) as cathode materials for sodium ion batteries (SIBs), including the stability of the desodiated structures, desodiation energy, redox mechanism, and the diffusion of Na. When 62.5% sodium is removed from NZO, its structure and volume change little and the layered structure is retained, whereas the structure starts to distort and shift to the ZrO3 phase with the extraction of more than 62.5% sodium. As desodiation proceeds, oxygen anions act as the only redox center for charge compensation, yielding a high initial voltage of 4.03 eV vs. Na/Na+ by PBE + U-D3 functional and 4.82 eV vs. Na/Na+ by HSE06-D3 functional. When the desodiation content is less than 31.25%, O23- is formed with an O-O distance of 2.38 Å. At the desodiation content of 31.25%, peroxide dimer O22- starts to form; at the desodiation content of 56.25%, the O-O bond distance is further shortened to 1.3 Å, corresponding to the formation of superoxide O2-. However, for Y-NZO, the redox reaction firstly involves O2-/O1-, which does not occur in NZO. Peroxides and superoxides appear when the sodium removal concentration is 59.38% and 75%, respectively. This indicates that the O-O dimers appear in Y-NZO at much deeper sodium removal. The calculations of diffusion paths and barriers of Na ions in NZO by PBE + U-D3 predict that the barrier of Na escaping from the mixed layer to the Na layer in NZO is 0.48 eV (the reverse barrier is 0.76 eV), smaller than those of other O3-type layered transition metal compounds, such as Na2IrO3 and Na2RuO3. After yttrium doping, the diffusion of Na ions becomes easier, indicating that the Y-doping improves the diffusion ability. This investigation interprets the mechanism of oxygen oxidation of NZO as a cathode for SIBs, and provides theoretical support for a better design of Na-rich layered oxide Na2MO3 (M represents the transition metal element) in the future research.

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