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1.
Mil Med Res ; 11(1): 36, 2024 Jun 11.
Artículo en Inglés | MEDLINE | ID: mdl-38863031

RESUMEN

BACKGROUND: Dysregulation of enhancer transcription occurs in multiple cancers. Enhancer RNAs (eRNAs) are transcribed products from enhancers that play critical roles in transcriptional control. Characterizing the genetic basis of eRNA expression may elucidate the molecular mechanisms underlying cancers. METHODS: Initially, a comprehensive analysis of eRNA quantitative trait loci (eRNAQTLs) was performed in The Cancer Genome Atlas (TCGA), and functional features were characterized using multi-omics data. To establish the first eRNAQTL profiles for colorectal cancer (CRC) in China, epigenomic data were used to define active enhancers, which were subsequently integrated with transcription and genotyping data from 154 paired CRC samples. Finally, large-scale case-control studies (34,585 cases and 69,544 controls) were conducted along with multipronged experiments to investigate the potential mechanisms by which candidate eRNAQTLs affect CRC risk. RESULTS: A total of 300,112 eRNAQTLs were identified across 30 different cancer types, which exert their influence on eRNA transcription by modulating chromatin status, binding affinity to transcription factors and RNA-binding proteins. These eRNAQTLs were found to be significantly enriched in cancer risk loci, explaining a substantial proportion of cancer heritability. Additionally, tumor-specific eRNAQTLs exhibited high responsiveness to the development of cancer. Moreover, the target genes of these eRNAs were associated with dysregulated signaling pathways and immune cell infiltration in cancer, highlighting their potential as therapeutic targets. Furthermore, multiple ethnic population studies have confirmed that an eRNAQTL rs3094296-T variant decreases the risk of CRC in populations from China (OR = 0.91, 95%CI 0.88-0.95, P = 2.92 × 10-7) and Europe (OR = 0.92, 95%CI 0.88-0.95, P = 4.61 × 10-6). Mechanistically, rs3094296 had an allele-specific effect on the transcription of the eRNA ENSR00000155786, which functioned as a transcriptional activator promoting the expression of its target gene SENP7. These two genes synergistically suppressed tumor cell proliferation. Our curated list of variants, genes, and drugs has been made available in CancereRNAQTL ( http://canernaqtl.whu.edu.cn/#/ ) to serve as an informative resource for advancing this field. CONCLUSION: Our findings underscore the significance of eRNAQTLs in transcriptional regulation and disease heritability, pinpointing the potential of eRNA-based therapeutic strategies in cancers.


Asunto(s)
Elementos de Facilitación Genéticos , Neoplasias , Sitios de Carácter Cuantitativo , Humanos , Elementos de Facilitación Genéticos/genética , Neoplasias/genética , Variación Genética/genética , Estudio de Asociación del Genoma Completo/métodos , Neoplasias Colorrectales/genética , Estudios de Casos y Controles , ARN/genética , China , ARN Potenciadores
2.
Discov Med ; 36(184): 882-897, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38798249

RESUMEN

Cardiovascular disease stands as the leading cause of death globally, with hypertension emerging as an independent risk factor for its development. The worldwide prevalence of hypertension hovers around 30%, encompassing a staggering 1.2 billion patients, and continues to escalate annually. Medication plays a pivotal role in managing hypertension, not only effectively regulating blood pressure (BP) but also substantially mitigating the occurrence of cardiovascular and cerebrovascular diseases. This review comprehensively outlines the categories, mechanisms, clinical applications, and drawbacks of conventional antihypertensive drugs. It delves into the five primary pharmacological classifications, namely ß-receptor blockers, calcium channel blockers (CCBs), angiotensin-converting enzyme inhibitors (ACEIs), angiotensin receptor blockers (ARBs), and diuretics. The emphasis is placed on elucidating the mechanisms, advantages, and research progress of novel antihypertensive drugs targeting emerging areas. These include mineralocorticoid receptor antagonists (MRAs), atrial natriuretic peptides (ANPs), neutral endopeptidase inhibitors (NEPIs), sodium-dependent glucose transporter 2 inhibitors (SGLT-2Is), glucagon-like peptide-1 receptor agonists (GLP-1RAs), endothelin receptor antagonists (ERAs), soluble guanylate cyclase (sGC) agonists, brain aminopeptidase A inhibitors (APAIs), and small interfering ribonucleic acids (siRNAs) targeting hepatic angiotensinogen. Compared to conventional antihypertensive drugs, these novel alternatives exhibit favorable antihypertensive effects with minimal adverse reactions. This review serves as a valuable reference for future research and the clinical application of antihypertensive drugs.


Asunto(s)
Inhibidores de la Enzima Convertidora de Angiotensina , Antihipertensivos , Hipertensión , Humanos , Antihipertensivos/uso terapéutico , Antihipertensivos/farmacología , Hipertensión/tratamiento farmacológico , Inhibidores de la Enzima Convertidora de Angiotensina/uso terapéutico , Inhibidores de la Enzima Convertidora de Angiotensina/farmacología , Antagonistas de Receptores de Angiotensina/uso terapéutico , Bloqueadores de los Canales de Calcio/uso terapéutico , Bloqueadores de los Canales de Calcio/farmacología , Animales , Antagonistas Adrenérgicos beta/uso terapéutico , Antagonistas Adrenérgicos beta/farmacología , Diuréticos/uso terapéutico , Diuréticos/farmacología , Antagonistas de Receptores de Mineralocorticoides/uso terapéutico
3.
Water Res ; 256: 121608, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38657310

RESUMEN

The application of ozone (O3) disinfection has been hindered by its low solubility in water and the formation of disinfection by-products (DBPs). In this study, capacitive disinfection is applied as a pre-treatment for O3 oxidation, in which manganese dioxide with a rambutan-like hollow spherical structure is used as the electrode to increase the charge density on the electrode surface. When a voltage is applied, the negative-charged microbes are attracted to the electrodes and killed by electrical interactions. The contact between microbes and capacitive electrodes leads to changes in cell permeability and burst of reactive oxygen species, thereby promoting the diffusion of O3 into the cells. After O3 penetrates the cell membrane, it can directly attack the cytoplasmic constituents, accelerating fatal and irreversible damage to pathogens. As a result, the performance of the capacitance-O3 process is proved better than the direct sum of the two individual process efficiencies. The design of capacitance-O3 system is beneficial to reduce the ozone dosage and DBPs with a broader inactivation spectrum, which is conducive to the application of ozone in primary water disinfection.


Asunto(s)
Desinfección , Compuestos de Manganeso , Óxidos , Ozono , Ozono/farmacología , Ozono/química , Óxidos/farmacología , Óxidos/química , Desinfección/métodos , Compuestos de Manganeso/química , Compuestos de Manganeso/farmacología , Membrana Celular/efectos de los fármacos , Purificación del Agua/métodos , Electrodos , Bacterias/efectos de los fármacos
4.
J Am Chem Soc ; 146(17): 11968-11977, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38630990

RESUMEN

The direct oxidation of CH4 to C2H5OH is attractive but challenging owing to the intricate processes involving carbon-chain growth and hydroxylation simultaneously. The inherent difficulty arises from the strong tendency of CH4 to overoxidize in the commonly used pressurized powder suspension systems rich in reactive oxygen radicals (ROR), which are specifically designed for CH4 concentration and activation. Meanwhile, the strong tendency of nucleophilic attack of potent ROR on the C-C bond of the resulting product C2H5OH ultimately leads to a higher selectivity for C1 oxygenates. This study addresses this multifaceted issue by designing a three-phase interface based on a hydrophilic floating Fe(III)-cross-linked macroporous alginate hydrogel film encapsulated with C3N4 [Fe(III)@ACN] to simultaneously enhance the accessibility of H2O and CH4 molecules to the active sites and species within the macroporous channel. The hydrophilic properties of Fe(III)@ACN allow the in situ production of H2O2 from C3N4 through the water oxidation reaction under irradiation. The concurrent photoinduced Fe(II) triggers Fenton reaction with H2O2 to produce •OH. The enhanced mass transfer of CH4 at the three-phase interface ensures the efficient formation of •CH3 by reacting with •OH, ultimately facilitating carbon-chain growth in the conversion pathway from CH4 to CH3OH and finally to C2H5OH with •CH3 and •OH present in comparable concentrations. Thus, the Fe(III)@ACN catalyst exhibits a remarkable 96% selectivity for alcohol, achieving a 90% selectivity for C2H5OH in the alcohol products. The C2H5OH production rate reaches 171.7 µmol g-1 h-1 without the need for precious-metal additive.

5.
J Phys Condens Matter ; 36(29)2024 Apr 25.
Artículo en Inglés | MEDLINE | ID: mdl-38593836

RESUMEN

We theoretically study the crossed Andreev reflection (CAR) of the normal metal-superconductor-normal metal (NSN) heterojunction based on Kekulé-Y patterned graphene with two doping types, i.e.nSnandnSpconfigurations. It is found that the enhanced CAR is more likely to occur in thenSpjunction rather than thenSnjunction. To be concrete, the almost perfect CAR occurs in a large range of incident angle in the single Dirac cone phase when the incident energy is inside the gap of the nonlinear band. Furthermore, the roles of the length of superconductor and pseudospin-valley coupling on conductance are also evaluated.

6.
Mol Genet Genomic Med ; 12(4): e2440, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38634212

RESUMEN

BACKGROUND: Malformations of cortical development (MCD) are a group of congenital disorders characterized by structural abnormalities in the brain cortex. The clinical manifestations include refractory epilepsy, mental retardation, and cognitive impairment. Genetic factors play a key role in the etiology of MCD. Currently, there is no curative treatment for MCD. Phenotypes such as epilepsy and cerebral palsy cannot be observed in the fetus. Therefore, the diagnosis of MCD is typically based on fetal brain magnetic resonance imaging (MRI), ultrasound, or genetic testing. The recent advances in neuroimaging have enabled the in-utero diagnosis of MCD using fetal ultrasound or MRI. METHODS: The present study retrospectively reviewed 32 cases of fetal MCD diagnosed by ultrasound or MRI. Then, the chromosome karyotype analysis, single nucleotide polymorphism array or copy number variation sequencing, and whole-exome sequencing (WES) findings were presented. RESULTS: Pathogenic copy number variants (CNVs) or single-nucleotide variants (SNVs) were detected in 22 fetuses (three pathogenic CNVs [9.4%, 3/32] and 19 SNVs [59.4%, 19/32]), corresponding to a total detection rate of 68.8% (22/32). CONCLUSION: The results suggest that genetic testing, especially WES, should be performed for fetal MCD, in order to evaluate the outcomes and prognosis, and predict the risk of recurrence in future pregnancies.


Asunto(s)
Variaciones en el Número de Copia de ADN , Diagnóstico Prenatal , Embarazo , Femenino , Humanos , Estudios Retrospectivos , Diagnóstico Prenatal/métodos , Ultrasonografía Prenatal/métodos , Pruebas Genéticas/métodos
7.
Curr Med Sci ; 44(2): 450-461, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38639827

RESUMEN

OBJECTIVE: Cymbopogon citratus (DC.) Stapf is a medicinal and edible herb that is widely used for the treatment of gastric, nervous and hypertensive disorders. In this study, we investigated the cardioprotective effects and mechanisms of the essential oil, the main active ingredient of Cymbopogon citratus, on isoproterenol (ISO)-induced cardiomyocyte hypertrophy. METHODS: The compositions of Cymbopogon citratus essential oil (CCEO) were determined by gas chromatography-mass spectrometry. Cardiomyocytes were pretreated with 16.9 µg/L CCEO for 1 h followed by 10 µmol/L ISO for 24 h. Cardiac hypertrophy-related indicators and NLRP3 inflammasome expression were evaluated. Subsequently, transcriptome sequencing (RNA-seq) and target verification were used to further explore the underlying mechanism. RESULTS: Our results showed that the CCEO mainly included citronellal (45.66%), geraniol (23.32%), and citronellol (10.37%). CCEO inhibited ISO-induced increases in cell surface area and protein content, as well as the upregulation of fetal gene expression. Moreover, CCEO inhibited ISO-induced NLRP3 inflammasome expression, as evidenced by decreased lactate dehydrogenase content and downregulated mRNA levels of NLRP3, ASC, CASP1, GSDMD, and IL-1ß, as well as reduced protein levels of NLRP3, ASC, pro-caspase-1, caspase-1 (p20), GSDMD-FL, GSDMD-N, and pro-IL-1ß. The RNA-seq results showed that CCEO inhibited the increase in the mRNA levels of 26 oxidative phosphorylation complex subunits in ISO-treated cardiomyocytes. Our further experiments confirmed that CCEO suppressed ISO-induced upregulation of mt-Nd1, Sdhd, mt-Cytb, Uqcrq, and mt-Atp6 but had no obvious effects on mt-Col expression. CONCLUSION: CCEO inhibits ISO-induced cardiomyocyte hypertrophy through the suppression of NLRP3 inflammasome expression and the regulation of several oxidative phosphorylation complex subunits.


Asunto(s)
Cymbopogon , Aceites Volátiles , Aceites Volátiles/farmacología , Inflamasomas/metabolismo , Proteína con Dominio Pirina 3 de la Familia NLR , Cymbopogon/química , Cymbopogon/metabolismo , Isoproterenol , Miocitos Cardíacos/metabolismo , Fosforilación Oxidativa , ARN Mensajero/metabolismo , Hipertrofia/inducido químicamente , Hipertrofia/tratamiento farmacológico , Hipertrofia/metabolismo
8.
Org Lett ; 26(15): 3097-3102, 2024 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-38574397

RESUMEN

This study introduces a novel approach involving XB-mediated cross-coupling of α-trifluoromethylated alkyl bromides with coumarins and quinolinones under visible light irradiation. Both density functional theory (DFT) calculations and experimental studies converge to suggest that the noncovalent interaction between alkyl bromides and DMAP, intensified by the α-trifluoromethyl group, plays a pivotal role in facilitating this chemoselective reaction.

9.
Histol Histopathol ; : 18739, 2024 Mar 27.
Artículo en Inglés | MEDLINE | ID: mdl-38606875

RESUMEN

BACKGROUND: Knee osteoarthritis (KOA) is one of the leading causes of disability. Polydatin has a potential effect on KOA treatment but the therapeutic mechanism is not clear. This study aims to investigate the therapeutic action of polydatin in KOA and its mechanism in activating autophagy via the AMP-activated protein kinase (AMPK)/mTOR signaling pathway. METHODS: After a KOA rat model was established by anterior cruciate ligament transection surgery, model rats were treated with polydatin 40 mg/kg for 30 days. Subsequently, cartilage tissues were collected, and hematoxylin-eosin (HE), Safranin-O, and TUNEL staining, and western blotting were performed to evaluate the pathological damage and autophagy-related protein expression. Then, human chondrocyte C28/I2 cells were stimulated with lipopolysaccharide (LPS), and the effects of polydatin on C28/I2 cell viability, apoptosis, and autophagy-related protein expression were detected by MTT, Flow Cytometry, and western blot. In addition, an AMPK inhibitor (Dorsomorphin 2HCl) was used to probe the cell proliferation and apoptosis of polydatin-administered C28/I2 cells. RESULTS: Polydatin ameliorated the pathological damage in rat cartilage tissues and inhibited cell apoptosis in KOA rats. Meanwhile, in C28/I2 cells, polydatin promoted viability and reduced apoptosis. In addition, the protein expression of collagen II, LC3II/LC3I, Beclin-1, and p-AMPK/AMPK were upregulated, and p62 and p-mTOR/mTOR were downregulated by polydatin treatment. Interestingly, relative results showed that the protective effect of polydatin in LPS-stimulated-C28/I2 cells was blocked by the AMPK/mTOR inhibitor, dorsomorphin 2HCl. CONCLUSION: Our research showed that polydatin reduced apoptosis and activated autophagy both in vivo and in vitro by the AMPK/mTOR signaling pathway to protect against KOA, which provided the basis for further investigation into the potential therapeutic impact of polydatin on KOA.

10.
Surg Infect (Larchmt) ; 25(3): 247-252, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38588519

RESUMEN

Background: The prevalence of community-onset infections of extended spectrum ß-lactamase (ESBL)-producing strains has increased globally, yet surveillance and resistance in patients with oral and maxillofacial surgery site infections is less investigated. Patients and Methods: A retrospective cohort study was performed to investigate risk factors and resistance of ESBL-producing Escherichia coli (ESBL-EC) and ESBL-producing Klebsiella pneumonia (ESBL-KP) among community-onset patients with oral and maxillofacial surgery during January 2010 to December 2016. Demographic features, predisposing factors, clinical outcomes, and antibiotic agent costs were analyzed. Antimicrobial susceptibility testing of nine antimicrobial agents against ESBL-KP and ESBL-EC were measured. Results: Among 2,183 cultures from infection sites in patients with oral and maxillofacial surgery site (45 cases [2.06%]) were confirmed with community-onset ESBL-KP (24; 1.10%) or ESBL-EC (21; 0.96%) infection. Multivariable analysis showed the independent risk factors for ESBL-producing bacterial infection were prior history of hospitalization (adjusted odds ratio [aOR], 10.984; 95% confidence interval [CI], 5.965-59.879; p = 0.025) and malignant condition (aOR, 3.373; 95% CI 2.947-7.634; p = 0.024). Based on antimicrobial susceptibility testing, 57.8% ESBL-KP and ESBL-EC were found receiving inappropriate antimicrobial therapy, and antibiotic agent costs were higher than non-ESBL-producing bacterial infections ($493.8 ± $367.3 vs. $304.1 ± $334.7; p = 0.031). Conclusions: Infections caused by ESBL-KP and ESBL-EC among patients in sites with oral and maxillofacial surgery are associated with prior history of hospitalization and malignant conditions. Prompt detection and appropriate antibiotic administration for community-onset infections of ESBLs are necessary for such populations.


Asunto(s)
Infecciones por Escherichia coli , Infecciones por Klebsiella , Neumonía , Humanos , Infecciones por Escherichia coli/tratamiento farmacológico , Infecciones por Escherichia coli/epidemiología , Infecciones por Escherichia coli/microbiología , Estudios Retrospectivos , beta-Lactamasas , Escherichia coli , Infecciones por Klebsiella/tratamiento farmacológico , Infecciones por Klebsiella/epidemiología , Klebsiella pneumoniae , Antibacterianos/farmacología , Antibacterianos/uso terapéutico , Factores de Riesgo , Klebsiella , Infección de la Herida Quirúrgica/tratamiento farmacológico , Infección de la Herida Quirúrgica/epidemiología
11.
Proc Natl Acad Sci U S A ; 121(16): e2319119121, 2024 Apr 16.
Artículo en Inglés | MEDLINE | ID: mdl-38588435

RESUMEN

The advancement of atomically precise dinuclear heterogeneous catalysts holds great potential in achieving efficient catalytic ozonation performance and contributes to the understanding of synergy mechanisms during reaction conditions. Herein, we demonstrate a "ship-in-a-bottle and pyrolysis" strategy that utilizes Fe2(CO)9 dinuclear-cluster to precisely construct Fe2 site, consisting of two Fe1-N3 units connected by Fe-Fe bonds and firmly bonded to N-doped carbon. Systematic characterizations and theoretical modeling reveal that the Fe-Fe coordination motif markedly reduced the devotion of the antibonding state in the Fe-O bond because of the strong orbital coupling interaction of dual Fe d-d orbitals. This facilitates O-O covalent bond cleavage of O3 and enhances binding strength with reaction intermediates (atomic oxygen species; *O and *OO), thus boosting catalytic ozonation performance. As a result, Fe dinuclear site catalyst exhibits 100% ozonation efficiency for CH3SH elimination, outperforming commercial MnO2 catalysts by 1,200-fold. This research provides insights into the atomic-level structure-activity relationship of ozonation catalysts and extends the use of dinuclear catalysts in catalytic ozonation and beyond.

12.
Zhongguo Dang Dai Er Ke Za Zhi ; 26(4): 403-409, 2024 Apr 15.
Artículo en Chino | MEDLINE | ID: mdl-38660905

RESUMEN

Further evidence is needed to explore the impact of high-altitude environments on the neurologic function of neonates. Non-invasive techniques such as cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography can provide data on cerebral oxygenation and brain electrical activity. This study will conduct multiple cerebral near-infrared spectroscopy and amplitude-integrated electroencephalography monitoring sessions at various time points within the first 3 days postpartum for healthy full-term neonates at different altitudes. The obtained data on cerebral oxygenation and brain electrical activity will be compared between different altitudes, and corresponding reference ranges will be established. The study involves 6 participating centers in the Chinese High Altitude Neonatal Medicine Alliance, with altitude gradients divided into 4 categories: 800 m, 1 900 m, 2 400 m, and 3 500 m, with an anticipated sample size of 170 neonates per altitude gradient. This multicenter prospective cohort study aims to provide evidence supporting the impact of high-altitude environments on early brain function and metabolism in neonates.


Asunto(s)
Altitud , Encéfalo , Electroencefalografía , Oxígeno , Humanos , Recién Nacido , Encéfalo/metabolismo , Oxígeno/metabolismo , Espectroscopía Infrarroja Corta , Estudios Prospectivos
13.
Dermatol Ther (Heidelb) ; 14(4): 893-906, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38483777

RESUMEN

INTRODUCTION: The necessity for tuberculosis preventive treatment (TPT) and routine T-SPOT.TB monitoring in patients with psoriasis and tuberculosis infection (TBI) undergoing interleukin (IL)-17A inhibitor therapy remains uncertain. This study aims to evaluate the long-term safety of IL-17A inhibitors administered without TPT and analyze changes in T-SPOT.TB among these patients. It also identifies risk factors for TBI in patients with psoriasis. METHODS: This single-center prospective study enrolled adult patients with plaque psoriasis and TBI receiving IL-17A inhibitors. TBI was defined as positive T-SPOT.TB results (≥ 6 spots) without symptoms or evidence of active tuberculosis (ATB). TPT administration was based on contraindications, tuberculosis risk factors, and patient preferences. The primary endpoint was the incidence of ATB over 2 years. Secondary outcomes included T-SPOT.TB changes and TBI risk factors. RESULTS: Of the 129 patients with psoriasis and TBI enrolled in the study, 97 (75.2%) did not receive TPT, while 32 (24.8%) did. Among them, 109 patients (84.5%) completed the 2-year follow-up. During the 235 person-years of observation, no ATB cases were identified. Median T-SPOT.TB values showed no significant changes from baseline to year 2 in both the non-TPT (20 vs. 17 spots, p = 0.975) and TPT groups (55 vs. 58 spots, p = 0.830). T-SPOT.TB reversed in 14 patients (12.8%), mostly in the non-TPT group. Moreover, for TBI risk factor analysis, a cohort of 212 patients with psoriasis with negative baseline T-SPOT.TB was evaluated, revealing a TBI prevalence of 37.8%. Logistic regression analysis highlighted age ≥ 45 years (odds ratio [OR] 2.44, 95% confidence interval [CI] 1.50-3.99, p < 0.001) and body mass index (BMI) < 24.0 kg/m2 (OR 2.12, 95% CI 1.27-3.54, p = 0.004) as independent risk factors for TBI. CONCLUSION: IL-17A inhibitors do not appear to reactivate tuberculosis in patients with psoriasis and TBI, potentially reducing the need for routine TBI screening and preventive treatment. TRIAL REGISTRATION: Chinese Clinical Trial Registry, ChiCTR2100045823.

14.
Small ; : e2311879, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38461527

RESUMEN

Carbon-defect engineering in single-atom metal-nitrogen-carbon (M─N─C) catalysts by straightforward and robust strategy, enhancing their catalytic activity for volatile organic compounds, and uncovering the carbon vacancy-catalytic activity relationship are meaningful but challenging. In this study, an iron-nitrogen-carbon (Fe─N─C) catalyst is intentionally designed through a carbon-thermal-diffusion strategy, exposing extensively the carbon-defective Fe─N4 sites within a micro-mesoporous carbon matrix. The optimization of Fe─N4 sites results in exceptional catalytic ozonation efficiency, surpassing that of intact Fe─N4 sites and commercial MnO2 by 10 and 312 times, respectively. Theoretical calculations and experimental data demonstrated that carbon-defect engineering induces selective cleavage of C─N bond neighboring the Fe─N4 motif. This induces an increase in non-uniform charges and Fermi density, leading to elevated energy levels at the center of Fe d-band. Compared to the intact atomic configuration, carbon-defective Fe─N4 site is more activated to strengthen the interaction with O3 and weaken the O─O bond, thereby reducing the barriers for highly active surface atomic oxygen (*O/*OO), ultimately achieving efficient oxidation of CH3 SH and its intermediates. This research not only offers a viable approach to enhance the catalytic ozonation activity of M─N─C but also advances the fundamental comprehension of how periphery carbon environment influences the characteristics and efficacy of M─N4 sites.

15.
Inorg Chem ; 63(12): 5761-5768, 2024 Mar 25.
Artículo en Inglés | MEDLINE | ID: mdl-38485515

RESUMEN

The reasonably constructed high-performance electrocatalyst is crucial to achieve sustainable electrocatalytic water splitting. Alloying is a prospective approach to effectively boost the activity of metal electrocatalysts. However, it is a difficult subject for the controllable synthesis of small alloying nanostructures with high dispersion and robustness, preventing further application of alloy catalysts. Herein, we propose a well-defined molecular template to fabricate a highly dispersed NiRu alloy with ultrasmall size. The catalyst presents superior alkaline hydrogen evolution reaction (HER) performance featuring an overpotential as low as 20.6 ± 0.9 mV at 10 mA·cm-2. Particularly, it can work steadily for long periods of time at industrial-grade current densities of 0.5 and 1.0 A·cm-2 merely demanding low overpotentials of 65.7 ± 2.1 and 127.3 ± 4.3 mV, respectively. Spectral experiments and theoretical calculations revealed that alloying can change the d-band center of both Ni and Ru by remodeling the electron distribution and then optimizing the adsorption of intermediates to decrease the water dissociation energy barrier. Our research not only demonstrates the tremendous potential of molecular templates in architecting highly active ultrafine nanoalloy but also deepens the understanding of water electrolysis mechanism on alloy catalysts.

17.
Small ; : e2400551, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38516940

RESUMEN

Electrocatalytic nitrogen reduction technology seamlessly aligns with the principles of environmentally friendly chemical production. In this paper, a comprehensive review of recent advancements in electrocatalytic NH3 synthesis utilizing single-atom catalysts (SACs) is offered. Into the research and applications of three categories of SACs: noble metals (Ru, Au, Rh, Ag), transition metals (Fe, Mo, Cr, Co, Sn, Y, Nb), and nonmetallic catalysts (B) in the context of electrocatalytic ammonia synthesis is delved. In-depth insights into the material preparation methods, single-atom coordination patterns, and the characteristics of the nitrogen reduction reaction (NRR) are provided. The systematic comparison of the nitrogen reduction capabilities of various SAC types offers a comprehensive research framework for their integration into electrocatalytic NRR. Additionally, the challenges, potential solutions, and future prospects of incorporating SACs into electrocatalytic nitrogen reduction endeavors are discussed.

18.
Org Biomol Chem ; 22(11): 2279-2283, 2024 Mar 13.
Artículo en Inglés | MEDLINE | ID: mdl-38407278

RESUMEN

Here, we demonstrate a practical method toward the facile synthesis of CF3-containing amino acids through visible light promoted decarboxylative cross-coupling of a redox-active ester with tert-butyl 2-(trifluoromethyl)acrylate. The reaction was driven by the photochemical activity of electron donor-acceptor (EDA) complexes that were formed by the non-covalent interaction between a Hantzsch ester and a redox-active ester. The advantages of this protocol are its synthetic simplicity, rich functional group tolerance, and a cost-effective reaction system.

19.
ACS Nano ; 18(8): 6579-6590, 2024 Feb 27.
Artículo en Inglés | MEDLINE | ID: mdl-38353995

RESUMEN

Excitonic effects significantly influence the selective generation of reactive oxygen species and photothermal conversion efficiency in photocatalytic reactions; however, the intrinsic factors governing excitonic effects remain elusive. Herein, a series of single-atom catalysts with well-defined M1-N3C1 (M = Mn, Fe, Co, and Ni) active sites are designed and synthesized to investigate the structure-activity relationship between photocatalytic materials and excitonic effects. Comprehensive characterization and theoretical calculations unveil that excitonic effects are positively correlated with the number of valence electrons in single metal atoms. The single Mn atom with 5.93 valence electrons exhibits the weakest excitonic effects, which dominate superoxide radical (O2•-) generation through charge transfer and enhance photothermal conversion efficiency. Conversely, the single Ni atom with 9.27 valence electrons exhibits the strongest excitonic effects, dominating singlet oxygen (1O2) generation via energy transfer while suppressing photothermal conversion efficiency. Based on the valence electron number dependent excitonic effects, a reaction environment with hyperthermia and abundant cytotoxic O2•- is designed, achieving efficient and stable water disinfection. This work reveals single metal atom dependent excitonic effects and presents an atomic-level methodology for catalytic application targeted reaction environment tailoring.

20.
Sensors (Basel) ; 24(2)2024 Jan 05.
Artículo en Inglés | MEDLINE | ID: mdl-38257420

RESUMEN

Hyperspectral images (HSIs) contain abundant spectral and spatial structural information, but they are inevitably contaminated by a variety of noises during data reception and transmission, leading to image quality degradation and subsequent application hindrance. Hence, removing mixed noise from hyperspectral images is an important step in improving the performance of subsequent image processing. It is a well-established fact that the data information of hyperspectral images can be effectively represented by a global spectral low-rank subspace due to the high redundancy and correlation (RAC) in the spatial and spectral domains. Taking advantage of this property, a new algorithm based on subspace representation and nonlocal low-rank tensor decomposition is proposed to filter the mixed noise of hyperspectral images. The algorithm first obtains the subspace representation of the hyperspectral image by utilizing the spectral low-rank property and obtains the orthogonal basis and representation coefficient image (RCI). Then, the representation coefficient image is grouped and denoised using tensor decomposition and wavelet decomposition, respectively, according to the spatial nonlocal self-similarity. Afterward, the orthogonal basis and denoised representation coefficient image are optimized using the alternating direction method of multipliers (ADMM). Finally, iterative regularization is used to update the image to obtain the final denoised hyperspectral image. Experiments on both simulated and real datasets demonstrate that the algorithm proposed in this paper is superior to related mainstream methods in both quantitative metrics and intuitive vision. Because it is denoising for image subspace, the time complexity is greatly reduced and is lower than related denoising algorithms in terms of computational cost.

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