A solvothermal method to prepare PtNi alloys that have differing morphologies is described. By adjusting the feed ratio of Pt and Ni precursors in this process, PtNi alloys with different ...compositions (Pt : Ni atomic ratio from 1 : 3 to 3 : 1) and morphologies (evolution from nanobranches to nanoparticles) are generated. The prepared Pt48Ni52 alloy, which has a composite morphology comprised of nanobranches and nanoparticles, exhibits superior activity and durability towards the hydrogen evolution reaction (HER) in seawater compared to those of commercial Pt/C catalyst and other PtNi alloys that have different compositions and morphologies. The excellent seawater HER performance of Pt48Ni52 is ascribed to its nanobranch/nanoparticle morphology that optimally facilitates electron accumulation on Pt, which enhances resistance to chloride corrosion in seawater.
Corrosion control: A PtNi alloy with a composite morphology comprised of nanobranches and nanoparticles is described. The unique morphology of the PtNi alloy facilitates electron accumulation on Pt, which enhances its resistance to chloride corrosion and performance in electrocatalytic hydrogen production in seawater.
Hierarchical porosity and functionalization help to fully make use of metal–organic frameworks (MOFs) for their diverse applications. Herein, a simple strategy is reported to construct hierarchically ...porous MOFs through a competitive coordination method using tetrafluoroborate (M(BF4)x, where M is metal site) as both functional sites and etching agents. The resulting MOFs have in situ formed defect‐mesopores and functional sites without sacrificing their structure stability. The formation mechanism of the defect‐mesopores is elucidated by a combination of experimental and first‐principles calculation method, indicating the general feasibility of this new approach. Compared with the original microporous counterparts, the new hierarchical MOFs exhibit superior adsorption for the bulky dye molecules and catalytic performance for the CO2 conversion attributed to their specific hierarchical pore structures.
A simple and novel strategy is reported to fabricate a series of hierarchically porous metal–organic frameworks through the competitive coordination method. The formation mechanism of defect‐mesopores is elucidated by a combination of experimental and first‐principles calculation methods. Furthermore, the adsorption and catalytic advantage over the original microporous counterparts is also demonstrated attributed to their specific hierarchical pore structures.
The homojunction of oxygen/metal vacancies and its interfacial n–p effect on the physiochemical properties are rarely reported. Interfacial n–p homojunctions of TiO2 are fabricated by directly ...decorating interfacial p‐type titanium‐defected TiO2 around n‐type oxygen‐defected TiO2 nanocrystals in amorphous–anatase homogeneous nanostructures. Experimental measurements and theoretical calculations on the cell lattice parameters show that the homojunction of oxygen and titanium vacancies changes the charge density of TiO2; a strong EPR signal caused by oxygen vacancies and an unreported strong titanium vacancies signal of 2D 1H TQ‐SQ MAS NMR are present. Amorphous–anatase TiO2 shows significant performance regarding the photogeneration current, photocatalysis, and energy storage, owing to interfacial n‐type to p‐type conductivity with high charge mobility and less structural confinement of amorphous clusters. A new “homojunction of oxygen and titanium vacancies” concept, characteristics, and mechanism are proposed at an atomic‐/nanoscale to clarify the generation of oxygen vacancies and titanium vacancies as well as the interface electron transfer.
The homojunction of oxygen and titanium vacancies developed in the amorphous–anatase interface of nanostructured TiO2 results in a unique n–p electronic transmission, which is mostly preferred to the mobility of electronic charge carriers. It also contributes to significant performance regarding photogeneration current, photocatalysis, and energy storage.
An electrocatalyst composed of RuO2 surrounded by interfacial carbon, is synthesized through controllable oxidization‐calcination. This electrocatalyst provides efficient charge transfer, numerous ...active sites, and promising activity for pH‐universal electrocatalytic overall seawater splitting. An electrolyzer with this catalyst gives current densities of 10 mA cm−2 at a record low cell voltage of 1.52 V, and shows excellent durability at current densities of 10 mA cm−2 for up to 100 h. Based on the results, a mechanism for the catalytic activity of the composite is proposed. Finally, a solar‐driven system is assembled and used for overall seawater splitting, showing 95% Faraday efficiency.
An electrocatalyst composed of RuO2 surrounded by interfacial carbon is synthesized through controllable oxidization‐calcination. The interfacial carbon in RuO2/carbon compositions can provide efficient charge transfer and enhanced structural stability for the RuO2, which exhibits promising activity for pH‐universal electrocatalytic overall seawater splitting and its application in the solar‐driven electrolyzer.
Summary
Background
There are limited data on the incidence of pneumonia and pneumonia‐related hospitalisation in the IBD population, and on any association of IBD medications with such outcomes.
Aims
...To evaluate the impact of IBD medications on the risk of pneumonia, pneumonia‐related hospitalisations and death.
Methods
We conducted a retrospective cohort study of IBD patients from the nationwide Veteran Affairs (VA) dataset. The exposure of interest was different IBD medication groups. We estimated the incidence rate of pneumonia, pneumonia‐related hospitalisation and mortality based on IBD medication subgroups. We used a multivariable Cox regression to estimate the adjusted hazard ratios (AHR) and 95% confidence intervals (CIs) for these outcomes.
Results
Out of 56 410 patients with IBD, 3759 developed pneumonia, 1489 were hospitalised, and 248 died within 30 days of their pneumonia diagnosis. The crude incidence rates of pneumonia, pneumonia‐related hospitalisation and pneumonia‐related mortality were 6.47, 2.52 and 0.43, respectively, per 1000 person‐years. In multivariable Cox regression analysis, compared to 5‐ASA alone, anti‐TNF medication was associated with an increased risk of pneumonia (AHR 1.39; 95% CI 1.22‐1.59) and hospitalisation (AHR 1.61; 95% CI 1.31‐1.98). Use of prednisone in the prior 30 days was associated with increased risk of pneumonia (AHR 2.14; 95% CI 1.92‐2.38) and hospitalisation (AHR 2.44; 95% CI 2.08‐2.88).
Conclusion
Anti‐TNF medications and prednisone use may be associated with increased risk of developing pneumonia and pneumonia‐related hospitalisation. Physicians should evaluate the risk–benefit ratio of IBD medications, especially in the elderly population.
CdS nanoparticles were introduced on E. coli cells to construct a hydrogen generating biohybrid system via the biointerface of tannic acid‐Fe complex. This hybrid system promotes good biological ...activity in a high salinity environment. Under light illumination, the as‐synthesized biohybrid system achieves a 32.44 % enhancement of hydrogen production in seawater through a synergistic effect.
Nanoncapsulation of E. coli by tannic acid (TA)‐Fe complexes enhances its stability in seawater. Further, different types of nanomaterials can be easily introduced to the surface of E. coli using TA−Fe shells as a biological interface. The E. coli‐based semiconductor biohybrid system prepared by nanoencapsulation and hybridisation can significantly enhance hydrogen production activity under illumination and shows good stability in seawater.
Age-related macular degeneration (AMD) is a devastating neurodegenerative disease and a major cause of blindness in the developed world. Owing to its complexity and the lack of an adequate human ...model that recapitulates key aspects of the disease, the molecular mechanisms of AMD pathogenesis remain poorly understood. Here we show that cultured human retinal pigment epithelium (RPE) from AMD donors (AMD RPE) are functionally impaired and exhibit distinct phenotypes compared with RPE cultured from normal donors (normal RPE). Accumulation of lipid droplets and glycogen granules, disintegration of mitochondria, and an increase in autophagosomes were observed in AMD RPE cultures. Compared with normal RPE, AMD RPE exhibit increased susceptibility to oxidative stress, produce higher levels of reactive oxygen species (ROS) under stress conditions, and showed reduced mitochondrial activity. Measurement of the ratio of LC3-II/ LC3-I, revealed impaired autophagy in AMD RPE as compared with normal RPE. Autophagic flux was also reduced in AMD RPE as compared with normal RPE, as shown by inability of AMD RPE to downregulate p62 levels during starvation. Impaired autophagic pathways were further shown by analyzing late autophagic vesicles; immunostaining with lysosome-associated membrane protein 1 (LAMP-1) antibody revealed enlarged and annular LAMP-1-positive organelles in AMD RPE as opposed to smaller discrete puncta observed in normal RPE. Our study provides insights into AMD cellular and molecular mechanisms, proposes dysfunctional autophagy as an underlying mechanism contributing to the pathophysiology of the disease, and opens up new avenues for development of novel treatment strategies.
ObjectiveGut microbiota influence metabolic pathways related to the pathogenesis of obesity, insulin-resistance and diabetes. Antibiotic therapy can alter the microbiota, and is commonly used in ...western countries. We sought to evaluate whether past antibiotic exposure increases diabetes risk.Research design and methodsWe conducted a nested case–control study using a large population-based database from the UK. The cases were defined as those with incident diagnosis of diabetes. For every case, four eligible controls matched on age, sex, practice-site, and duration of follow-up before index-date were selected using incidence-density sampling. Exposure of interest was antibiotic therapy >1 year before index-date. Odds ratios (ORs) and 95% CIs were estimated using conditional logistic regression. The risk was adjusted for BMI, smoking, last glucose level, and number of infections before index-date, as well as past medical history of coronary artery disease and hyperlipidaemia.ResultsThe study included 208 002 diabetic cases and 815 576 matched controls. Exposure to a single antibiotic prescription was not associated with higher adjusted diabetes risk. Treatment with two to five antibiotic courses was associated with increase in diabetic risk for penicillin, cephalosporins, macrolides and quinolones with adjusted OR ranging from 1.08 (95% CI 1.05–1.11) for penicillin to 1.15 (95% CI 1.08–1.23) for quinolones. The risk increased with the number of antibiotic courses and reached 1.37 (95% CI 1.19–1.58) for more than 5 courses of quinolones. There was no association between exposure to anti-virals and anti-fungals and diabetes risk.ConclusionsExposure to certain antibiotic groups increases diabetes risk.
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