Cross-linked α-Ni(OH)2 nanosheets with a Ni3+-rich structure for accelerating electrochemical oxidation of 5-hydroxymethylfurfural.

Electrochemical oxidation of biomass-based 5-hydroxymethylfurfural (HMF) is an effective approach for achieving the high-value products of 2,5-furandicarboxylic acid (FDCA). However, the restricted formation of high-valence metal active species for electrocatalysts results in a sluggish kinetic process of HMF oxidation reaction (HMFOR). Herein, we fabricated the Ni3+-rich cross-linked α-Ni(OH)2 nanosheets for accelerating the HMFOR through an anion-mediated strategy. It is identified that the Cl- ions with strong penetrability replace a portion of lattice oxygen atoms in α-Ni(OH)2 to form Ni-Cl bonds, contributing to breaking the inherent lattice order and generating a special Ni3+-rich structure. Owing to the promoted adsorption and accelerated oxidation of hydroxyl and aldehyde groups by the affluent Ni3+ active species, the large oxidation current density of 116.5 mA cm-2 and HMFOR kinetic constant of 0.067 min-1 has been achieved at 1.45 V (vs. RHE). By analyzing the oxidation products, the FDCA yield and Faradic efficiency are both higher than 99.25 % and 99.36 % for five successive determinations. Therefore, this work provides an insightful anion-mediated strategy for designing high-performance electrocatalysts for biomass conversion application.

Cerebral Protection of Intraoperative Infusion of Dexmedetomidine in Patients with Chronic Cerebrovascular Stenosis Undergoing Endovascular Interventional Therapies: A Prospective Randomized Controlled Trial.

BACKGROUND: To investigate the cerebral protective effect of intraoperative dexmedetomidine infusion on patients with chronic cerebral vascular stenosis receiving endovascular interventional therapy. METHODS: Sixty patients with carotid artery or cerebral artery stenosis or occlusion stenting under elective general anesthesia were divided into dexmedetomidine group (group D) and normal saline group (group N). Group D was given dexmedetomidine loading dose 1.0 µg/kg after peripheral vein opening for 10 min, and then adjusted infusion rate to 0.5 µg/kg/h until stopped 30 min before end. RESULTS: At 7 days after operation, the contents of S100ß, neuron-specific enolase (NSE) and interleukin-6 (IL-6) in group D were apparently lower than those in group N (P < 0.05), while the contents of IL-1ß and tumor necrosis factor-α in 2 groups showed no statistical significance (P > 0.05). Additionally, at 4 days and 7 days after operation, the scores of Mini-Mental State Scale (MMSE) and Wechsler Memory Scale (WMS) in group D were significantly higher than those in group N (P < 0.05). Thirty days after surgery, the cerebral hemodynamic indexes (relative mean transit time, relative time to peak) in group D were significantly improved, and obviously better than those in group N (P < 0.05). CONCLUSIONS: The S-100ß, NSE, and inflammatory mediator IL-6 in group D were significantly decreased compared with group N, the MMSE and WMS cognitive function scores, and the cerebral blood perfusion were apparently improved in group D, clarifying dexmedetomidine has protective effect on nerve tissue injury by inhibiting inflammation.

Underestimation about the Contribution of Nitrate Reducers to Iron Cycling Indicated by Enterobacter Strain.

Nitrate-reducing iron(II) oxidation (NRFO) has been intensively reported in various bacteria. Iron(II) oxidation is found to be involved in both enzymatic and chemical reactions in nitrate-reducing Fe(II)-oxidizing microorganisms (NRFOMs). However, little is known about the relative contribution of biotic and abiotic reactions to iron(II) oxidation for the common nitrate reducers during the NRFO process. In this study, the typical nitrate reducers, four Enterobacter strains E. hormaechei, E. tabaci, E. mori and E. asburiae, were utilized as the model microorganisms. The comparison of the kinetics of nitrate, iron(II) and nitrite and N2O production in setups with and without iron(II) indicates a mixture of enzymatic and abiotic oxidation of iron(II) in all four Enterobacter strains. It was estimated that 22-29% of total oxidized iron(II) was coupled to microbial nitrate reduction by E. hormaechei, E. tabaci, E. mori, and E. asburiae. Enterobacter strains displayed an metabolic inactivity with heavy iron(III) encrustation on the cell surface in the NRFOmedium during days of incubation. Moreover, both respiratory and periplasmic nitrate-reducing genes are encoded by genomes of Enterobacter strains, suggesting that cell encrustation may occur with periplasmic iron(III) oxide precipitation as well as the surface iron(II) mineral coating for nitrate reducers. Overall, this study clarified the potential role of nitrate reducers in the biochemical cycling of iron under anoxic conditions, in turn, re-shaping their activity during denitrification because of cell encrustation with iron(III) minerals.

Prevalence of Antibiotic Resistome in Ready-to-Eat Salad.

Ready-to-eat salad harbors microorganisms that may carry various antibiotic resistance genes (ARGs). However, few studies have focused on the prevalence of ARGs on salad, thus underestimating the risk of ARGs transferring from salad to consumers. In this small-scale study, high-throughput quantitative PCR was used to explore the presence, prevalence and abundance of ARGs associated with serving salad sourced from two restaurant types, fast-food chain and independent casual dining. A total of 156 unique ARGs and nine mobile genetic elements (MGEs) were detected on the salad items assessed. The abundance of ARGs and MGEs were significantly higher in independent casual dining than fast-food chain restaurants. Absolute copies of ARGs in salad were 1.34 × 107 to 2.71 × 108 and 1.90 × 108 to 4.87 × 108 copies per g salad in fast-food and casual dining restaurants, respectively. Proteobacteria, Bacteroidetes, Actinobacteria, and Firmicutes were the dominant bacterial phyla detected from salad samples. Pseudomonas, Acinetobacter, Exiguobacterium, Weissella, Enterobacter, Leuconostoc, Pantoea, Serratia, Erwinia, and Ewingella were the 10 most dominant bacterial genera found in salad samples. A significant positive correlation between ARGs and MGEs was detected. These results integrate knowledge about the ARGs in ready-to-eat salad and highlight the potential impact of ARGs transfer to consumers.

High-flow nasal cannula oxygen therapy and hypoxia during gastroscopy with propofol sedation: a randomized multicenter clinical trial.

BACKGROUND AND AIMS: Hypoxia is one of the most frequent adverse events with sedated GI endoscopy and can lead to serious consequences. No modalities have been found previously to prevent hypoxia. High-flow nasal cannula (HFNC) supportive oxygen therapy provides heated and humidified oxygen up to 60 L/minute. Because of its ability to improve respiratory function and good tolerance, we aimed to evaluate the validity and safety of HFNC supportive oxygen therapy in preventing the incidence of hypoxia in patients undergoing gastroscopy with propofol sedation. METHODS: In a multicenter, prospective randomized single-blinded study, 1994 outpatients undergoing routine gastroscopy with propofol sedation provided by an anesthesiologist were randomized into 2 groups: the nasal cannula group (O2 [2 L/minute] was supplied via an HFNC) and the HFNC group (O2 [30-60 L/minute] was supplied via an HFNC) at 3 centers from November 2017 to February 2018. The primary outcome was the incidence of hypoxia. Other adverse events were also recorded. RESULTS: HFNC supportive oxygen therapy decreased the incidence of hypoxia (75% ≤ Spo2 < 90% for <60 seconds) and severe hypoxia (Spo2 < 75% for any duration or 75% ≤ Spo2 < 90% for ≥60 seconds) from 8.4% to 0% (P < .001) and from 0.6% to 0% (P = .03), respectively. The only HFNC-related adverse event was xeromycteria/rhinalgia (1.7%), which was observed 1 minute after the procedure and disappeared after 30 minutes. CONCLUSIONS: HFNC supportive oxygen therapy can prevent the incidence of hypoxia and severe hypoxia in patients in America Society of Anesthesiologists class I-II undergoing elective gastroscopy under propofol sedation, with minimal related adverse events and good tolerance. (Clinical trial registration number: NCT03332433.).

Core-shell nanomaterials: Applications in energy storage and conversion.

Materials with core-shell structures have attracted increasing attention in recent years due to their unique properties and wide applications in energy storage and conversion systems. Through reasonable adjustments of their shells and cores, various types of core-shell structured materials can be fabricated with favorable properties that play significant roles in energy storage and conversion processes. The core-shell material can provide an effective solution to the current energy crisis. Various synthetic strategies used to fabricate core-shell materials, including the atomic layer deposition, chemical vapor deposition and solvothermal method, are briefly mentioned here. A state-of-the -art review of their applications in energy storage and conversion is summarized. The involved energy storage includes supercapacitors, li-ions batteries and hydrogen storage, and the corresponding energy conversion technologies contain quantum dot solar cells, dye-sensitized solar cells, silicon/organic solar cells and fuel cells. In addition, the correlation between the core-shell structures and their performance in energy storage and conversion is introduced, and this finding can provide guidance in designing original core-shell structures with advanced properties.