A new calibration method for radon detector in seismic systems

Radon observation is an important measurement item of seismic precursor network observation.The radon detector calibration is a key technical link for ensuring radon observation accuracy.At present,the radon detector calibration in seismic systems in China is faced with a series of bottleneck problems,such as aging and scrap,acquisition difficulties,high supervision costs,and transportation limitations of radon sources.As a result,a large number of radon detectors cannot be accurately calibrated regularly,seriously affecting the accuracy and reliability of radon observation data in China.To solve this problem,a new calibration method for radon detectors was established.The advantage of this method is that the dangerous radioactive substance,i.e.,the radon source,can be avoided,but only“standard instruments”and water samples with certain dissolved radon concentrations can be used to realize radon detector calibration.This method avoids the risk of radioactive leakage and solves the current widespread difficulties and bottleneck of radon detector calibration in seismic systems in China.The comparison experiment with the traditional calibration method shows that the error of the calibration coefficient obtained by the new method is less than 5%compared with that by the traditional method,which meets the requirements of seismic observation systems,confirming the reliability of the new method.This new method can completely replace the traditional calibration method of using a radon source in seismic systems.

One Stone Four Birds:A Novel Liposomal Delivery System Multi-functionalized with Ginsenoside Rh2 for Tumor Targeting Therapy

Liposomes hold great potential in anti-cancer drug delivery and the targeting treatment of tumors.However,the clinical therapeutic efficacy of liposomes is still limited by the complexity of tumor microenvironment(TME)and the insufficient accumulation in tumor sites.Meanwhile,the application of cholesterol and polyethylene glycol(PEG),which are usually used to prolong the blood circulation and stabilize the structure of liposomes respectively,has been questioned due to various disadvantages.Herein,we developed a ginsenoside Rh2-based multifunctional liposome system(Rh2-lipo)to effectively address these challenges once for all.Different with the conventional’wooden’liposomes,Rh2-lipo is a much more brilliant carrier with multiple functions.In Rh2-lipo,both cholesterol and PEG were substituted by Rh2,which works as membrane stabilizer,long-circulating stealther,active targeting ligand,and chemotherapy adjuvant at the same time.Firstly,Rh2 could keep the stability of liposomes and avoid the shortcomings caused by cholesterol.Secondly,Rh2-lipo showed a specifically prolonged circulation behavior in the blood.Thirdly,the accumulation of the liposomes in the tumor was significantly enhanced by the interaction of glucose transporter of tumor cells with Rh2.Fourth,Rh2-lipo could remodel the structure and reverse the immunosuppressive environment in TME.When tested in a 4T1 breast carcinoma xenograft model,the paclitaxel-loaded Rh2-lipo realized high efficient tumor growth suppression.Therefore,Rh2-lipo not only innovatively challenges the position of cholesterol as a liposome component,but also provides another innovative potential system with multiple functions for anti-cancer drug delivery.

Effect of the structure of ginsenosides on the in vivo fate of their liposomes

To utilize themultiple functions and give full play of ginsenosides,a variety of ginsenosides with different structures were prepared into liposomes and evaluated for their effect on the stability,pharmacokinetics and tumor targeting capability of liposomes.The results showed that the position and number of glycosyl groups of ginsenosides have significant effect on the in vitro and in vivo properties of their liposomes.The pharmacokinetics of ginsenosides liposomes indicated that the C-3 sugar group of ginsenosides is beneficial to their liposomes for longer circulation in vivo.The C-3 and C-6 glycosyls can enhance the uptake of their liposomes by 4T1 cells,and the glycosyls at C-3 position can enhance the tumor active targeting ability significantly,based on the specific binding capacity to Glut 1 expressed on the surface of 4T1 cells.According to the results in the study,ginsenoside Rg3 and ginsenoside Rh2 are potential for exploiting novel liposomes because of their cholesterol substitution,long blood circulation and tumor targeting capabilities.The results provide a theoretical basis for further development of ginsenoside based liposome delivery systems.

Recent advances in ionic liquids-based hybrid processes for CO_(2) capture and utilization

CO_(2) capture and utilization(CCU)is an effective strategy to mitigate global warming.Absorption,adsorption and membranes are methods used for CO_(2) separation and capture,and various catalytic pathways have also been developed for CO_(2) utilization.Although widely researched and used in industry,these processes are energy-intensive and this challenge needs to be overcome.To realize further optimization,novel materials and processes are continuously being developed.New generation materials such as ionic liquids(ILs)have shown promising potential for cost-effective CO_(2) capture and utilization.This study reviews the current status of ILs-based solvents,adsorbents,membranes,catalysts and their hybrid processes for CO_(2) capture and utilization.The special properties of ILs are integrated into new materials through hybridization,which significantly improves the performance in the process of CCU.