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Electrochemical nitrate reduction reaction (NO3RR) is a promising approach to realize ammonia generation and wastewater treatment. However, the transformation from NO3 - to NH3 involves multiple proton-coupled electron transfer processes and by-products (NO2 -, H2, etc.), making high ammonia selectivity a challenge. Herein, a two-phase nanoflower P-Cu/Co(OH)2 electrocatalyst consisting of P-Cu clusters and P-Co(OH)2 nanosheets is designed to match the two-step tandem process (NO3 - to NO2 - and NO2 - to NH3) more compatible, avoiding excessive NO2 - accumulation and optimizing the whole tandem reaction. Focusing on the initial 2e- process, the inhibited *NO2 desorption on Cu sites in P-Cu gives rise to the more appropriate NO2 - released in electrolyte. Subsequently, P-Co(OH)2 exhibits a superior capacity for trapping and transforming the desorbed NO2 - during the latter 6e- process due to the thermodynamic advantage and contributions of active hydrogen. In 1 m KOH + 0.1 m NO3 -, P-Cu/Co(OH)2 leads to superior NH3 yield rate of 42.63 mg h- 1 cm- 2 and NH3 Faradaic efficiency of 97.04% at -0.4 V versus the reversible hydrogen electrode. Such a well-matched two-step process achieves remarkable NH3 synthesis performance from the perspective of optimizing the tandem catalytic reaction, offering a novel guideline for the design of NO3RR electrocatalysts.
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The characteristics of dopamine self-polymerization were used to cover the nano-titanium dioxide (TiO2) surface and produce nano-titanium dioxide-polydopamine (TiO2-PDA). The reducing nature of dopamine was then used to reduce silver nitrate to silver elemental particles on the modified nano-titanium dioxide: The resulting TiO2-PDA-Ag nanoparticles were used as antimicrobial agents. Finally, the antibacterial agent was mixed with silicone to obtain an antibacterial silicone composite material. The composition and structure of antibacterial agents were analyzed by scanning electron microscopy, transmission electron microscopy, X-ray photoelectron energy spectroscopy, and X-ray diffraction. Microscopy and the antibacterial properties of the silicone antibacterial composites were studied as well. The TiO2-PDA-Ag antimicrobial agent had good dispersion versus nano-TiO2. The three were strongly combined with obvious characteristic peaks. The antibacterial agents were evenly dispersed in silicone, and the silicone composite has excellent antibacterial properties. Bacillus subtilis (B. subtilis) adhesion was reduced from 246 × 104 cfu/cm2 to 2 × 104 cfu/cm2, and colibacillus (E. coli) reduced from 228 × 104 cfu/cm2 leading to bacteria-free adhesion.
Assuntos
Bacillus subtilis , Escherichia coli , Silicones , Prata , Titânio , Titânio/química , Titânio/farmacologia , Silicones/química , Prata/química , Prata/farmacologia , Escherichia coli/efeitos dos fármacos , Bacillus subtilis/efeitos dos fármacos , Nanopartículas Metálicas/química , Antibacterianos/farmacologia , Antibacterianos/química , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Polímeros/química , Polímeros/farmacologia , Difração de Raios X , Testes de Sensibilidade Microbiana , Aderência Bacteriana/efeitos dos fármacos , IndóisRESUMO
Improving the selective ammonia production capacity of electrocatalytic nitrate reduction reaction (NO3 RR) at ambient conditions is critical to the future development and industrial application of electrosynthesis of ammonia. However, the reaction involves multi-proton and electron transfer as well as the desorption and underutilization of intermediates, posing a challenge to the selectivity of NO3 RR. Here the electrodeposition site of Co is modulated by depositing Bi at the bottom of the catalyst, thus obtaining the Co+Bi@Cu NW catalyst with a Bi-Co corridor structure. In 50 mm NO3 - , Co+Bi@Cu NW exhibits a highest Faraday efficiency of ≈100% (99.51%), an ammonia yield rate of 1858.2 µg h-1 cm-2 and high repeatability at -0.6 V versus the reversible hydrogen electrode. Moreover, the change of NO2 - concentration on the catalyst surface observed by in situ reflection absorption imaging and the intermediates of the NO3 RR process detected by electrochemical in situ Raman spectroscopy together verify the NO2 - trapping effect of the Bi-Co corridor structure. It is believed that the measure of modulating the deposition site of Co by loading Bi element is an easy-to-implement general method for improving the selectivity of NH3 production as well as the corresponding scientific research and applications.
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OBJECTIVE: Thyroid cancer has been an increasingly high-profile public health issue. Comprehensive assessment for its disease burden seems particularly important for understanding health priorities and hinting high-risk populations. METHODS: We estimated the age-sex-specific thyroid cancer burden and its temporal trend in China from 1990 to 2019 by following the general methods from the global burden of disease (GBDs) 2019 Study. And Joinpoint regression model, the Cox-Stuart trend test, and Cochran-Armitage test were applied for the analysis of temporal and age trend. The Mantel-Haenszel statistical method was used to compare the gender difference. RESULTS: From 1990 to 2019, the age-standardized incidence rate of thyroid cancer in China has almost doubled to 2.05 per 100,000. Although the mortality rate and DALY rate kept leveling off, they presented a downtrend among females, while an upward trend in males. While the average annual percentage changes of those metrics all became deline since 2010 than the previous years. With age advancing, the rates of incidence, mortality, and DALYs for both sexes all presented linear fashion increases, which was particularly typical among males. CONCLUSION: Given the serious trend and gender-age heterogeneity of Chinese thyroid cancer burden, male gender and advanced age may be related to poor prognosis of thyroid cancer, and strengthening primary prevention and exploring the underlying risk factors should be among the top priorities.
Assuntos
Efeitos Psicossociais da Doença , Neoplasias da Glândula Tireoide , Feminino , Humanos , Masculino , Anos de Vida Ajustados por Qualidade de Vida , Incidência , Neoplasias da Glândula Tireoide/epidemiologia , China/epidemiologiaRESUMO
Cardiovascular diseases (CVDs), which are associated with high morbidity and mortality worldwide, include atherosclerosis (AS), hypertension, heart failure (HF), atrial fibrillation, and myocardial fibrosis. CVDs are influenced by the diversity, distribution, and metabolites of intestinal microflora, and their risk can be reduced through physical activity (PA) such as regular exercise. PA benefits the metabolic changes that occur in the gut microbiota (GM). The major metabolites of the GM influence pathogenesis of CVDs through various pathways. However, the relationship between PA and GM is less well understood. In this review, we discuss the impacts of different types of PA on intestinal microflora including the diversity, distribution, metabolites, and intestinal barrier function including intestinal permeability, with a focus on the mechanisms by which PA affects GM. We also discuss how GM influences CVDs. Finally, we summarize current research and knowledge on the effects of PA on CVD via regulation of the GM and intestinal function. More understanding of relevant relationship between PA and GM may provide hope for the prevention or treatment of CVDs. Furthermore, a better understanding of regulation of the GM and intestinal function may lead to novel diagnostic and therapeutic strategies, improving the clinical care of CVD patients.
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Doenças Cardiovasculares , Microbioma Gastrointestinal , Hipertensão , Doenças Cardiovasculares/diagnóstico , Exercício Físico , Humanos , IntestinosRESUMO
Background and purpose. A single nucleotide polymorphism at nucleotide 196 (G/A) in the human brain-derived neurotrophic factor (BDNF) gene produces an amino acid substitution (valine to methionine) at codon 66(Val66Met). It is unclear whether carriers of this substitution may have worse functional outcomes after stroke. We aimed to explore the distribution of Val66Met polymorphism and evaluate the effect of different genotypes on stroke functional recovery. Methods. Several databases were searched using the keywords BDNF or brain-derived neurotrophic factor, codon66, G196A, rs6265, or Val66Met, and stroke. Results. A total of 25 articles were relevant to estimate the distribution of alleles; 5 reports were applied in the meta-analysis to assess genetic differences on recovery outcomes. The genetic model analysis showed that the recessive model should be used; we combined data for AA versus GA+GG (GG-Val/Val, GA-Val/Met, AA-Met/Met). The results showed that stroke patients with AA might have worse recovery outcomes than those with GA+GG (odds ratio = 1.90; 95% CI: 1.17-3.10; P = .010; I2 = 69.2%). Overall, the A allele may be more common in Asian patients (48.6%; 95% CI: 45.8%-51.4%, I2 = 54.2%) than Caucasian patients (29.8%; 95% CI: 7.5%-52.1%; I2 = 99.1%). However, in Caucasian patients, the frequency of the A allele in Iranians (87.9%; 95% CI: 83.4%-92.3%) was quite higher than that in other Caucasians (18.7%; 95% CI: 16.6%-20.9%; I2 = 0.00%). Conclusion. Val66Met AA carriers may have worse rehabilitation outcomes than GA+GG carriers. Further studies are needed to determine the effect of Val66Met polymorphism on stroke recovery and to evaluate this relationship with ethnicity, sex, age, stroke type, observe duration, stroke severity, injury location, and therapies.