Simultaneous transcatheter intervention for atrial septal defect complicated with patent ductus arteriosus: A 13-year single institutional retrospective study

Purpose: The feasibility and validity of simultaneous transcatheter interventions for patients with atrial septal defect(ASD) complicated with patent ductus arteriosus(PDA) has not been systematically evaluated. Materials and Methods: A retrospective analysis was conducted in patients who received transcatheter procedures for ASD complicated with PDA concurrently. The indications and treatment protocols were in accordance with the current guidelines. The sequence of therapy for ASD complicated with PDA was determined by clinical experience. Patients were followed up for at least 6 months after therapy Results: Overall, 22 patients received simultaneous transcatheter interventional therapy, and the success rate was a 100%. No severe complications transpired during the procedure or follow-up stage. Conclusion: Simultaneous transcatheter intervention is feasible and effective for patients who have concurrent complications for both ASD and PDA.

Silk-based hydrogel incorporated with metal-organic framework nanozymes for enhanced osteochondral regeneration

Osteochondral defects(OCD)cannot be efficiently repaired due to the unique physical architecture and the pathological microenvironment including enhanced oxidative stress and inflammation.Conventional strategies,such as the control of implant microstructure or the introduction of growth factors,have limited functions failing to manage these complex environments.Here we developed a multifunctional silk-based hydrogel incorporated with metal-organic framework nanozymes(CuTA@SF)to provide a suitable microenvironment for enhanced OCD regeneration.The incorporation of CuTA nanozymes endowed the SF hydrogel with a uniform microstructure and elevated hydrophilicity.In vitro cultivation of mesenchymal stem cells(MSCs)and chondrocytes showed that CuTA@SF hydrogel accelerated cell proliferation and enhanced cell viability,as well as had antioxidant and antibacterial properties.Under the inflammatory environment with the stimulation of IL-1β,CuTA@SF hydrogel still possessed the potential to promote MSC osteogenesis and deposition of cartilage-specific extracellular matrix(ECM).The proteomics analysis further confirmed that CuTA@SF hydrogel promoted cell proliferation and ECM synthesis.In the full-thickness OCD model of rabbit,CuTA@SF hydrogel displayed successfully in situ OCD regeneration,as evidenced by micro-CT,histology(HE,S/O,and toluidine blue staining)and immunohistochemistry(Col I and aggrecan immunostaining).Therefore,CuTA@SF hydrogel is a promising biomaterial targeted at the regeneration of OCD.

Optimization of COVID-19 prevention and control measures during the Beijing 2022 Winter Olympics:a model-based study

Background:The continuous mutation of severe acute respiratory syndrome coronavirus 2 has made the coronavirus disease 2019(COVID-19)pandemic complicated to predict and posed a severe challenge to the Beijing 2022Winter Olympics and Winter Paralympics held in February and March 2022.Methods:During the preparations for the Beijing 2022 Winter Olympics,we established a dynamic model with pulsedetection and isolation efect to evaluate the efect of epidemic prevention and control measures such as entry policies,contact reduction,nucleic acid testing,tracking,isolation,and health monitoring in a closed-loop managementenvironment,by simulating the transmission dynamics in assumed scenarios.We also compared the importance ofeach parameter in the combination of intervention measures through sensitivity analysis.Results:At the assumed baseline levels,the peak of the epidemic reached on the 57th day.During the simulationperiod(100 days),13,382 people infected COVID-19.The mean and peak values of hospitalized cases were 2650and 6746,respectively.The simulation and sensitivity analysis showed that:(1)the most important measures to stopCOVID-19 transmission during the event were daily nucleic acid testing,reducing contact among people,and dailyhealth monitoring,with cumulative infections at 0.04%,0.14%,and 14.92%of baseline levels,respectively(2)strictlyimplementing the entry policy and reducing the number of cases entering the closed-loop system could delay thepeak of the epidemic by 9 days and provide time for medical resources to be mobilized;(3)the risk of environmentaltransmission was low.Conclusions:Comprehensive measures under certain scenarios such as reducing contact,nucleic acid testing,health monitoring,and timely tracking and isolation could efectively prevent virus transmission.Our research resultsprovided an important reference for formulating prevention and control measures during the Winter Olympics,andno epidemic spread in the closed-loop during the games indirectly proved the rationality of our research results.

A sampling method based on forecasting and combinatorial optimization for high performance A/B testing

1 Introduction A/B testing[1]is a popular statistical method for many applications,especially,widely used by Internet companies for user experience research.The sampling algorithm is an important part of A/B testing and has a critical impact on the performance of A/B testing.There are two challenges to achieving high performance in A/B testing.(1)The features of individuals being sampled change over time and the sampling results used for evaluation are valid only for a period of time.(2)The sampling methods in A/B testing require determining whether the two groups of samples have an identical distribution while Simple Random Sampling(SRS)has a different purpose,which only concerns whether the sample distribution is identical to the population.