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Genetic studies have identified numerous regions associated with plasma fibrinogen levels in Europeans, yet missing heritability and limited inclusion of non-Europeans necessitates further studies with improved power and sensitivity. Compared with array-based genotyping, whole genome sequencing (WGS) data provides better coverage of the genome and better representation of non-European variants. To better understand the genetic landscape regulating plasma fibrinogen levels, we meta-analyzed WGS data from the NHLBI's Trans-Omics for Precision Medicine (TOPMed) program (n=32,572), with array-based genotype data from the Cohorts for Heart and Aging Research in Genomic Epidemiology (CHARGE) Consortium (n=131,340) imputed to the TOPMed or Haplotype Reference Consortium panel. We identified 18 loci that have not been identified in prior genetic studies of fibrinogen. Of these, four are driven by common variants of small effect with reported MAF at least 10 percentage points higher in African populations. Three signals (SERPINA1, ZFP36L2, and TLR10) contain predicted deleterious missense variants. Two loci, SOCS3 and HPN, each harbor two conditionally distinct, non-coding variants. The gene region encoding the fibrinogen protein chain subunits (FGG;FGB;FGA), contains 7 distinct signals, including one novel signal driven by rs28577061, a variant common in African ancestry populations but extremely rare in Europeans (MAFAFR=0.180; MAFEUR=0.008). Through phenome-wide association studies in the VA Million Veteran Program, we found associations between fibrinogen polygenic risk scores and thrombotic and inflammatory disease phenotypes, including an association with gout. Our findings demonstrate the utility of WGS to augment genetic discovery in diverse populations and offer new insights for putative mechanisms of fibrinogen regulation.
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Here Fe2O(SeO3)2/Fe3C@NC catalysts with high performance were fabricated for zinc-air batteries (ZABs). The experimental results confirmed that the existence of Fe-O-Se bonds in Fe2O(SeO3)2 crystal phase, and the Fe-O-Se bonds could obviously enhance ORR and OER catalytic performance of Fe2O(SeO3)2/Fe3C@NC. Density functional theoretical calculations (DFT) confirmed that the Fe2O(SeO3)2 in Fe2O(SeO3)2/Fe3C@NC had a higher d-band center of Fe atom and a lower p-orbital coupling degree with its own lattice O atom than Fe2O3, which leads to Fe site of Fe2O(SeO3)2 being more likely to adsorb external oxygen intermediates. The Fe-O-Se bonds in Fe2O(SeO3)2 results in the modification of coordination environment of Fe atoms and optimizes the adsorption energy of Fe site for oxygen intermediates. Compared with Fe2O3/Fe3C@NC, the Fe2O(SeO3)2/Fe3C@NC showed obvious enhancements of ORR/OER catalytic activities with a half-wave potential of 0.91 V for ORR in 0.1 M KOH electrolyte and a low overpotential of 345 mV for OER at 10 mA cm-2 in a 1.0 M KOH electrolyte. The peak power density and specific capacity of Fe2O(SeO3)2/Fe3C@NC-based ZABs are higher than those of Pt/C+RuO2-ZABs. The above results demonstrate that the asymmetrical Fe-O-Se bonds in Fe2O(SeO3)2 plays a key role in improving the bifunctional catalytic activities of ORR/OER for ZABs.
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[This corrects the article DOI: 10.1016/j.isci.2024.110255.].
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ABSTRACT: The relaxation of trapezius muscles is widely believed to alleviate fatigue or injury of the trapezius muscles and reduce the risk of shoulder and neck pain. This study aims to examine the effects of different muscle relaxation techniques on the physical properties of the trapezius muscle and to explore how changes in the physical properties of the upper trapezius muscle affect those of the middle trapezius muscle. Twenty-four healthy males (mean age: 23.08 ± 0.97 years; height: 172.42 ± 4.61 cm; weight: 66.38 ± 6.68 kg; and body mass index: 22.30 ± 1.81 kg/m2), randomly divided into four groups: stretching relaxation group (ST, n = 6), mechanical vibration massage (MV, n = 6), pulse massage (PU, n = 6), and control (CO, n = 6). Measurements using the Myoton digital muscle assessment system were conducted daily over 2 weeks. The experimental groups demonstrated a notable decrease in tension and stiffness, accompanied by heightened elasticity in the upper trapezius muscles. Conversely, the control group exhibited contrasting trends. Although no significant variances were detected among the relaxation techniques, all proved efficacious compared to the control group (P < 0.05). Moreover, relaxation of the upper trapezius muscles significantly influenced the middle trapezius muscles (P < 0.05). Various relaxation methods positively influenced trapezius muscle attributes over 2 weeks, with inter-regional effects noted.
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Masaje , Relajación Muscular , Músculos Superficiales de la Espalda , Humanos , Masculino , Músculos Superficiales de la Espalda/fisiología , Relajación Muscular/fisiología , Adulto Joven , Masaje/métodos , Adulto , Ejercicios de Estiramiento Muscular , Vibración/uso terapéuticoRESUMEN
Iminothioindoxyl (ITI) is a new class of photoswitch that exhibits many excellent properties including well-separated absorption bands in the visible region for both conformers, ultrafast Z to E photoisomerization as well as the millisecond reisomerization at room temperature for the E isomer, and switchable ability in both solids and various solvents. However, the underlying ultrafast photoisomerization mechanism at the atomic level remains unclear. In this work, we have employed a combination of high-level RMS-CASPT2-based static electronic structure calculations and nonadiabatic dynamics simulations to investigate the ultrafast photoisomerization dynamics of ITI. Based on the minimum-energy structures, minimum-energy conical intersections, linear interpolation internal coordinate paths, and nonadiabatic dynamics simulations, the overall photoisomerization scenario of ITI upon excitation is established. Upon excitation around 416 nm, the molecule will be excited to the S2 state considering its close energy to the experimentally measured absorption maximum and larger oscillator strength, from which ultrafast decay of S2 to S1 state can take place efficiently with a time constant of 62 fs. However, the photoisomerization is not likely to complete in the S2 state since the dihedral associated with the Z to E isomerization changes little during the relaxation. Upon relaxing to the S1 state, the molecule will decay to the S0 state ultrafast with a time constant of 232 fs. In contrast, the decay of the S1 state is important for the isomerization considering that the dihedral related to the isomerization of the hopping structures is close to 90°. Therefore, the S1/S0 intersection region should be important for the isomerization of ITI. Arriving at the S0 state, the molecule can either go back to the original Z reactant or isomerize to the E products. At the end of the 500 fs simulation time, the E configuration accounts for nearly 37% of the final structures. Moreover, the photoisomerization mechanism is different from the isomerization mechanism in the ground state; i.e., instead of the inversion mechanism in the ground state, the photoisomerization prefers the rotation mechanism. Our results not only agree well with previous experimental studies but also provide some novel insights that could be helpful for future improvements in the performance of the ITI photoswitches.
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Leukaemia-related protein 16 (LRP16) has been found to be highly expressed in various tumours and to be related to poor prognosis. However, the role of LRP16 in endometrial carcinoma remains to be explored. We aimed to investigate the prognosis and role of LRP16 in endometrial carcinoma. Overall, 160 endometrial carcinoma (EC) tissues and 60 benign samples were collected. The expression of LRP16 protein in EC tissues was significantly increased compared with that in normal endometrial tissues, and high LRP16 expression was related to poor patient prognosis. Reduced LRP16 expression markedly inhibited cancer cell growth. The proliferation rates in the prophylactic bilateral salpingectomy (PBS) group and the shNon group were 0.727 ±0.015 and 0.743 ±0.009, respectively, while the proliferation rate in the shLRP16 group was only 0.373 ±0.012. The migration experiment showed that the number of cells passing through the basement membrane in the shLRP16 group was 34.2 ±5.1, which was significantly different to the shNon (161.6 ±7.8) and PBS groups (138.0 ±7.2). The results of the invasion experiment showed that the number of cells was 39.2 ±6.2 in the shLRP16 group, 146.7 ±8.2 in the shNon group, and 141.2 ±8.1 in the PBS group ( p < 0.05). Leukaemia-related protein 16 is highly expressed in oestrogen-dependent EC and may promote cancer cell growth.
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Biomarcadores de Tumor , Proliferación Celular , Neoplasias Endometriales , Humanos , Femenino , Neoplasias Endometriales/patología , Neoplasias Endometriales/metabolismo , Persona de Mediana Edad , Biomarcadores de Tumor/metabolismo , Biomarcadores de Tumor/análisis , Anciano , Línea Celular Tumoral , Movimiento Celular , Adulto , Neoplasias Hormono-Dependientes/patología , Neoplasias Hormono-Dependientes/metabolismo , Estrógenos/metabolismo , Hidrolasas de Éster CarboxílicoRESUMEN
The comprehensive utilization of sustainable green energy is essential to face the global energy and environmental crisis. The oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and electrocatalytic urea synthesis (EUS) are the pivotal electrocatalytic processes, necessitating the development of low-cost electrocatalysts with high efficiency. Small-sized transition metal oxide (TMO) clusters have attracted a lot of attention because of their exceptional qualities, such as exhibiting a dense array of low-coordinated metal active sites (e.g. abundant metal cation defects and oxygen vacancy), amorphous structures with high surface energy, high atom utilization efficiency, and cost-effectiveness. Furthermore, the synergistic actions between metal clusters and TM-Nx single atom active sites remarkably boost up the electrocatalytic performances, corroborated by density functional theory (DFT). More efforts in this comprehensive feature article are expected to achieve insights into the fundamental understanding of electrocatalytic reaction mechanisms in our lab and serve as a guide for creating cutting-edge electrocatalysts of transition metal oxide clusters.
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Water electrolysis has become an attractive hydrogen production method. Oxygen evolution reaction (OER) is a bottleneck of water splitting as its four-electron transfer procedure presents sluggish reaction kinetics. Designing composite catalysts with high performance for efficient OER still remains a huge challenge. Here, the P-doped cobalt oxide/NiFe layered double hydroxides (P-CoOX/NiFe LDHs) composite catalysts with amorphous/crystalline interfaces are successfully prepared for OER by hydrothermal-electrodeposition combined method. The results of electrochemical characterizations, operando Raman spectra, and DFT theoretical calculations have demonstrated the electrons in the P-CoOX/NiFe LDHs heterointerfaces are easily transferred from Ni2+ to Co3+ because that the amorphous configuration of P-CoOX can well induce Ni-O-Co orbital coupling. The electron transfer of Ni2+ to the surrounding Fe3+ and Co3+ will lead to the unoccupied eg orbitals of Ni3+ that can promote water dissociation and accelerate *OOH migration to improve OER catalytic performance. The optimized P-CoOX/NiFe LDHs exhibit superior catalytic performance for OER with a very low overpotential of 265 mV at 300 mA cm-2 and excellent long-term stability of 500 h with almost no attenuation at 100 mA cm-2. This work will provide a new method to design high-performance NiFe LDHs-based catalysts for OER.
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Flexible rechargeable Zn-air batteries (FZABs) exhibit high energy density, ultra-thin, lightweight, green, and safe features, and are considered as one of the ideal power sources for flexible wearable electronics. However, the slow and high overpotential oxygen reaction at the air cathode has become one of the key factors restricting the development of FZABs. The improvement of activity and stability of bifunctional catalysts has become a top priority. At the same time, FZABs should maintain the battery performance under different bending and twisting conditions, and the design of the overall structure of FZABs is also important. Based on the understanding of the three typical configurations and working principles of FZABs, this work highlights two common strategies for applying bifunctional catalysts to FZABs: 1) powder-based flexible air cathode and 2) flexible self-supported air cathode. It summarizes the recent advances in bifunctional oxygen electrocatalysts and explores the various types of catalyst structures as well as the related mechanistic understanding. Based on the latest catalyst research advances, this paper introduces and discusses various structure modulation strategies and expects to guide the synthesis and preparation of efficient bifunctional catalysts. Finally, the current status and challenges of bifunctional catalyst research in FZABs are summarized.
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BACKGROUND: Giant salamander protein peptide is a peptide with rich functional properties. Giant salamander protein peptide KGEYNK (KK-6) is a peptide with both antioxidant and anti-inflammatory properties. The antioxidant and anti-inflammatory mechanisms of KK-6 are still unclear. When we studied the functional mechanism of KK-6, we found that the antioxidant property of KK-6 has a synergistic and promoting effect on anti-inflammatory properties. RESULTS: KK-6 enhances cellular resistance to LPS via the MAPK/NF-κB signaling pathway, leading to increased levels of inflammatory factors: interleukin-1ß (764.81 ng mL-1), interleukin-6 (1.06 ng mL-1) and tumor necrosis factor-α (4440.45 ng mL-1). KK-6 demonstrates potent antioxidant properties by activating the Nrf2 signaling pathway, resulting in elevated levels of antioxidant enzymes (glutathione peroxidase: 0.03 µg mL-1; superoxide dismutase: 0.589 µg mL-1) and a reduction in the concentration of the oxidative product malondialdehyde (967.05 µg mL-1). CONCLUSION: Our findings highlight the great potential of KK-6, a peptide extracted from giant salamander protein, as a remedy for intestinal inflammation. Through its dual role as an antioxidant and anti-inflammatory agent, KK-6 offers a promising avenue for alleviating inflammation-related damage and oxidative stress. This study lays the foundation for further exploration of giant salamander products and highlights their importance in health and novel food development. © 2024 Society of Chemical Industry.
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Three chromomycin derivatives, chromomycins A3 (1, CA3), A5 (2, CA5), and monodeacetylchromomycin A3 (3, MDA-CA3), were identified from the soil-derived Streptomyces sp. CGMCC 26516. A reinvestigation of the structure of CA5 is reported, of which the absolute configuration was unambiguously determined for the first time to be identical with that of CA3 based on nuclear magnetic resonance (NMR) data analysis as well as NMR and electronic circular dichroism calculations. Compounds 1-3 showed potent cytotoxicity against the non-small-cell lung cancer (NSCLC) cells (A549, H460, H157-c-FLIP, and H157-LacZ) and down-regulated the protein expression of c-FLIP in A549 cells. The IC50 values of chromomycins in H157-c-FLIP were higher than that in H157-LacZ. Furthermore, si-c-FLIP promoted anti-proliferation effect of chromomycins in NSCLC cells. In nude mice xenograft model, 1 and 2 both showed more potent inhibition on the growth of H157-lacZ xenografts than that of H157-c-FLIP xenografts. These results verify that c-FLIP mediates the anticancer effects of chromomycins in NSCLC.
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The degradation of Belamcanda chinensis (L.) DC. polysaccharides was carried out by five concentrations of trifluoroacetic acid (TFA) (1-5 mol/L), and their physicochemical properties, degradation kinetics and anticomplementary activity were investigated. The findings revealed a notable reduction in the molecular weight of BCP, from an initial value of 2.622 × 105 g/mol to a final value of 6.255 × 104 g/mol, and the water solubility index increased from 90.66 ± 0.42 % to 97.78 ± 0.43 %. The degraded polysaccharides of B. chinensis exhibited a comparable monosaccharide composition comprising Man, GalA, Glc, Gal, and Ara. As the concentration of TFA increased, the degradation rate constant increased from 1.468 × 10-3 to 5.943 × 10-3, and the process followed the first-order degradation kinetic model (R2 > 0.97) and the random fracture model (R2 > 0.96). Furthermore, the five degraded polysaccharides still exhibit good thermal stability. In vitro experiments showed that DBCP-3 exhibited more potent anticomplementary activity than the original polysaccharides and positive drugs, which was strongly correlated with its Mw (r = 0.6-0.8), inhibiting complement activation by blocking C2 and C4. These results indicated that TFA degradation has a positive effect on polysaccharides, of which DBCP-3 is expected to treat diseases involving hyperactivation of the complement system.
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Peso Molecular , Polisacáridos , Ácido Trifluoroacético , Polisacáridos/química , Polisacáridos/farmacología , Ácido Trifluoroacético/química , Cinética , Monosacáridos/análisis , Monosacáridos/química , Animales , Solubilidad , Caryophyllaceae/química , Activación de Complemento/efectos de los fármacosRESUMEN
The effect on catalytic behavior induced by different morphology of NiO supports has been investigated using the example of gold-catalyzed CO oxidation. Three NiO-supported nanogold consisting of nanogold deposited onto NiO nanorods (NiO-R), nanosheet (NiO-S), and nanodiscs (NiO-D) were prepared. Transmission electron microscopy(TEM)/Scanning transmission electron microscopy(STEM) investigations indicated that Au particles dominantly exposed Au(111) facets virtually independent of NiO architectures. Au/NiO-S displayed a normal Arrhenius-type behavior. Au/NiO-R and Au/NiO-D showed an atypical behavior, characterized by a U-shaped curve of activity vs. temperature, which is attributed to the carbonate accumulation on whose catalytically active sites. On Au/NiO-R, a stable CO-conversion rate of 1.78 molCO gAu -1 h-1 at 30°C was achieved, which is among the higher rates reported so far for supported Au-based systems. DRIFTS measurement identified Auδ+ species as crucial CO adsorption sites promoting CO oxidation, and the catalytic CO oxidation should obey Mars-van Krevelen (<200°C) and Eley-Rideal mechanism (>240°C).
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ETHNOPHARMACOLOGICAL RELEVANCE: Danggui Sini Decoction (DGSD), which is commonly used to treat sciatica, has been shown to have an analgesic effect, but the underlying mechanisms are unclear. Here, Danggui Sini Decoction was shown to normalize the intestinal microbiota and serum metabolite levels to exert an analgesic effect. AIM OF THE STUDY: This study aimed to elucidate the therapeutic effects of DGSD on sciatica and the underlying mechanisms involved. METHODS: In this study, we conducted chronic constriction injury (CCI) model. Mecobalamin and DGSD were administered to CCI rats. Behavioural tests were used to examine the therapeutic effects of the drugs. UHPLC was used to identify DGSD components. 16S rRNA gene sequencing analysis of the intestinal flora was used to analyse the effect of DGSD on the intestinal microbiota. UHPLCâMS/MS was used to identify blood metabolites. KEGG pathway analysis of differentially abundant metabolites was subsequently conducted. ELISA was used to measure the serum inflammatory factor levels, and correlation analysis between the serum inflammatory factor levels and intestinal microbe abundance was conducted. PCR, western blotting, and immunohistochemical staining were used to validate the results of the KEGG pathway analysis. RESULTS: After CCI, the rats exhibited obvious thermal hyperalgesia; disruption of sciatic nerve structure; increased IL1α, SP, CCL5, and PGE2 levels; decreased IL10 levels in the blood; increased IL1ß, IL6, COX2, MMP9, nNOS, and p-NF-κB levels; and decreased IL4 levels in the sciatic nerve. In addition, CCI led to increased abundances of Peptostreptococcaceae, Leuconostocaceae, Christensenellaceae, Akkermansiaceae, Staphylococcaceae, Romboutsia, Marvinbryantia, Turicibacter, Weissella, UCG-005, Christensenellaceae_R-7_group, Akkermansia, Staphylococcus, Romboutsia_ilealis, Weissella_paramesenteroides, and Akkermansia_muciniphila and decreased abundances of Lactobacillaceae, Lactobacillus, Lactobacillus_murinus, and Lactobacillus_johnsonii. Correlation analysis indicated that Turicibacter abundance was most strongly related to IL1α, PGE2, IL10, and CCL5 levels, while norank_o_Coriobacteriales abundance had the weakest relationship with SP levels. KEGG pathway analysis of the differentially abundant metabolites revealed that the 'NF-kappa B signalling pathway' was involved in sciatica. DGSD reduced the levels of inflammatory factors, including IL1α, SP, CCL5, PGE2, IL6, COX2, and MMP9, in the blood and sciatic nerve and inhibited nNOS and NF-κB phosphorylation. DGSD improved the abundance of probiotics, including Lactobacillus and Blautia, and lowered the abundance of harmful bacteria, including Romboutsia, Turicibacter, and Weissella. DGSD promoted the repair of the injured sciatic nerve. CONCLUSIONS: DGSD can treat sciatica by inhibiting intestinal microbiota disorders induced by CCI in rats, normalizing inflammatory factor levels, and promoting nerve repair.
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Medicamentos Herbarios Chinos , Microbioma Gastrointestinal , Ratas Sprague-Dawley , Ciática , Animales , Microbioma Gastrointestinal/efectos de los fármacos , Medicamentos Herbarios Chinos/farmacología , Masculino , Ciática/tratamiento farmacológico , Ratas , Analgésicos/farmacología , Modelos Animales de Enfermedad , ARN Ribosómico 16SRESUMEN
The highly efficient photo-oxidation of alcohols has sparked significant potential to cope with environmental pollution and the ever-increasing energy crisis. This study reports a unique Ti3C2/BiOBr (TB) heterojunction with a rich inter-face based on in situ exfoliation of MXene and subsequently anchored onto BiOBr sheets. The TB nano-composites exhibited substantially improved photo-catalytic activity towards the photo-oxidation of benzyl alcohol (BA) to benzaldehyde and achieved a formation rate of 1.73 mmol g-1 h-1, greater than pristine BiOBr. The ultra-thin inter-facial contact boosted the oxygen vacancies (Ov) and Ti3+ and possessed the most negative adsorption energy, which boosted the transfer and separation of inter-facial charge carriers and the adsorption and dissociation of BA. Overall, the successful synthesis of TB composite, along with its exceptional photo-catalytic performance, offers valuable insights for applications in green chemistry and environmental remediation.
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The abnormal aggregation of Aß has been considered one of the primary causative factors for Alzheimer's disease. Diverse molecular entities have been developed to mitigate the formation of toxic Aß aggregates within the brain by inhibiting Aß aggregation. Recognizing that many FDA-approved drugs are derived from natural products, we present a summary of recent discoveries involving natural product molecules with inhibitory effects on Aß aggregation. By consolidating these findings, our review offers researchers a concise overview of the latest advancements in natural product-based interventions for Alzheimer's disease.
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Enfermedad de Alzheimer , Péptidos beta-Amiloides , Productos Biológicos , Agregado de Proteínas , Productos Biológicos/química , Productos Biológicos/farmacología , Productos Biológicos/síntesis química , Péptidos beta-Amiloides/antagonistas & inhibidores , Péptidos beta-Amiloides/metabolismo , Humanos , Enfermedad de Alzheimer/tratamiento farmacológico , Enfermedad de Alzheimer/metabolismo , Agregado de Proteínas/efectos de los fármacos , Estructura MolecularRESUMEN
BACKGROUND: Increased risk of venous thromboembolism (VTE) is a life-threatening side effect for users of oral contraceptives (OCs) or hormone therapy (HT). OBJECTIVES: To investigate the potential for genetic predisposition to VTE in OC or HT users, we conducted a gene-by-environment case-only meta-analysis of genome-wide association studies (GWAS). METHODS: Use or nonuse of OCs (7 studies) or HT (8 studies) at the time of the VTE event was determined by pharmacy records or self-report. A synergy index (SI) was modeled for each variant in each study and submultiplicative/supramultiplicative gene-by-environment interactions were estimated. The SI parameters were first meta-analyzed across OC and HT studies and subsequently meta-analyzed to obtain an overall estimate. The primary analysis was agnostic GWAS and interrogated all imputed genotypes using a P value threshold of <5.0 × 10-8; secondary analyses were candidate-based. RESULTS: The VTE case-only OC meta-analysis included 2895 OC users and 6607 nonusers; the case-only HT meta-analysis included 2434 HT users and 12 793 nonusers. In primary GWAS meta-analyses, no variant reached genome-wide significance, but the smallest P value approached statistical significance: rs9386463 (P = 5.03 × 10-8). We tested associations for 138 candidate variants and identified 2 that exceeded statistical significance (0.05/138 = 3.62 × 10-4): F5 rs6025 (P = 1.87 × 10-5; SI, 1.29; previously observed) and F11 rs2036914 (P = 2.0 × 10-4; SI, 0.91; new observation). CONCLUSION: The candidate variant approach to identify submultiplictive/supramultiplicative associations between genetic variation and OC and HT use identified a new association with common genetic variation in F11, while the agnostic interrogations did not yield new discoveries.
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Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Tromboembolia Venosa , Humanos , Tromboembolia Venosa/genética , Tromboembolia Venosa/epidemiología , Tromboembolia Venosa/inducido químicamente , Femenino , Factores de Riesgo , Adulto , Interacción Gen-Ambiente , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Medición de Riesgo , Anticonceptivos Hormonales Orales/efectos adversos , Anticonceptivos Hormonales Orales/administración & dosificación , Variación Genética , Terapia de Reemplazo de Estrógeno/efectos adversosRESUMEN
Compared to Ir, Ru-based catalysts often exhibited higher activity but suffered significant and rapid activity loss during the challenging oxygen evolution reaction (OER) in a corrosive acidic environment. Herein, we developed a hybrid MnRuOx catalyst in which the RuO2 microcrystalline regions serve as a supporting framework, and the amorphous MnRuOx phase fills the microcrystalline interstices. In particular, the MnRuOx-300 catalyst from an annealing temperature of 300 °C contains an optimal amorphous/crystalline heterostructure, providing substantial defects and active sites, facilitating efficient adsorption and conversion of OH-. In addition, the heterostructure leads to a relative increase of the d-band center close to the Fermin level, thus accelerating electron transfer with reduced charge transfer resistance at the active interface between crystalline and amorphous phases during the OER. The catalyst was further thoroughly evaluated under various operating conditions and demonstrated exceptional activity and stability for the OER, representing a promising solution to replace Ir in water electrolyzers.
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Electrocatalytic conversion of nitrates and carbon dioxide to urea under ambient conditions shows promise as a potential substitute for traditional urea synthesis processes characterized by high consumption and pollution. In this study, a straightforward one-pot method is employed to prepare a highly efficient FeNC-Fe1N4 electrocatalyst, consisting of atomically dispersed Fe1N4 sites and metallic Fe clusters (FeNC) with particle size of 4-7 nm. The FeNC-Fe1N4 catalyst exhibits remarkable electrocatalytic activity for urea synthesis from nitrate anion (NO3 -) and carbon dioxide (CO2), achieving a urea production rate of 38.2 mmol gcat -1 h-1 at -0.9 V (vs RHE) and a Faradaic efficiency of 66.5% at -0.6 V (vs RHE). Both experimental and theoretical results conclusively demonstrate that metallic Fe clusters and Fe1N4 species provide active sites for the adsorption and activation of NO3 - and CO2, respectively, and the synergistic effect between Fe1N4 and metallic Fe clusters significantly enhances the electrochemical efficiency of urea synthesis. In all, this work contributes to the rational design and comprehensive synthesis of a dual-active site iron-based electrocatalyst, facilitating efficient and sustainable urea synthesis.