Atomic-level-designed copper atoms on hierarchically porous gold architectures for high-efficiency electrochemical CO reduction

Electrochemical CO_(2) reduction is a promising technology for solving the CO_(2) emission problems and producing value-added products. Here, we report a hierarchically porous Cu1Au single-atom alloy(SAA) as an efficient electrocatalyst for CO_(2) reduction. Benefiting from the hierarchically porous architectures with abundant vacancies as well as three-dimensional accessible active sites, the as-prepared nanoporous Cu1Au SAA catalyst shows remarkable CO_(2) reduction performance with nearly 100% CO Faraday efficiency in a wide potential range(-0.4 to -0.9 V vs. reversible hydrogen electrode. The in-situ X-ray absorption spectroscopy studies and density functional theory calculations reveal that the Cu-Au interface sites serve as the intrinsic active centers,which can facilitate the activated adsorption of CO_(2) and stabilize the *COOH intermediate.

Effectiveness of intravenous r- tPA versus UK for acute ischaemic stroke: a nationwide prospective Chinese registry study

Background Intravenous recombinant tissue plasminogen activator(r-tPA)and urokinase(UK)are both recommended for the treatment of acute ischaemic stroke(AIS)in China,but with few comparative outcome data being available.We aimed to compare the outcomes of these two thrombolytic agents for the treatment of patients within 4.5 hours of onset of AIS in routine clinical practice in China.Methods A pre-planned,prospective,nationwide,multicentre,real-world registry of consecutive patients with AIS(age≥18 years)who received r-tPA or UK within 4.5 hours of symptom onset according to local decision-making and guideline recommendations during 2017-2019.The primary effectiveness outcome was the proportion of patients with an excellent functional outcome(defined by modified Rankin scale scores 0 to 1)at 90 days.The key safety endpoint was symptomatic intracranial haemorrhage according to standard definitions.Multivariable logistic regression was used for comparative analysis,with adjustment according to propensity scores to ensure balance in baseline characteristics.Results Overall,4130 patients with AIS were registered but 320 had incomplete or missing data,leaving 3810 with available data for analysis of whom 2666 received r-tPA(median dose 0.88(IQR 0.78-0.90)mg/kg)and 1144 received UK(1.71(1.43-2.00)×104 international unit per kilogram).There were several significant intergroup differences in patient characteristics:r-tPA patients were more educated,had less history of stroke,lower systolic blood pressure,greater neurological impairment and shorter treatment times from symptom onset than UK patients.However,in adjusted analysis,the frequency of excellent outcome(OR 1.18,95%CI 1.00 to 1.40,p=0.052)and symptomatic intracranial haemorrhage(OR 0.70,95%CI 0.33 to 1.47,p=0.344)were similar between groups.Conclusions UK may be as effective and carry a similar safety profile as r-tPA in treating mild to moderate AIS within guidelines in China.Registration http://www.clinicaltrials.gov.unique identifier:NCT02854592.