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This was a phase 1 dose-escalation study of ZR202-CoV, a recombinant protein vaccine candidate containing a pre-fusion format of the spike (S)-protein (S-trimer) combined with the dual-adjuvant system of Alum/CpG. A total of 230 participants were screened and 72 healthy adults aged 18–59 years were enrolled and randomized to receive two doses at a 28-day interval of three different ZR202-CoV formulations or normal saline. We assessed the safety for 28 days after each vaccination and collected blood samples for immunogenicity evaluation. All formulations of ZR202-CoV were well-tolerated, with no observed solicited adverse events ≥ Grade 3 within 7 days after vaccination. No unsolicited adverse events ≥ Grade 3, or serious adverse events related to vaccination occurred as determined by the investigator. After the first dose, detectable immune responses were observed in all subjects. All subjects that received ZR202-CoV seroconverted at 14 days after the second dose by S-binding IgG antibody, pseudovirus and live-virus based neutralizing antibody assays. S-binding response (GMCs: 2708.7 ~ 4050.0 BAU/mL) and neutralizing activity by pseudovirus (GMCs: 363.1 ~ 627.0 IU/mL) and live virus SARS-CoV-2 (GMT: 101.7 ~ 175.0) peaked at 14 days after the second dose of ZR202-CoV. The magnitudes of immune responses compared favorably with COVID-19 vaccines with reported protective efficacy.

Glycerol is a new green organic solvent. It not only acts as a phase transfer catalyst but also as a recyclable solvent by significantly enhancing the intramolecular cyclization. A series of 4-aryl-7,7 -dimethyl-5-oxo-3,4,5,6,7,8-hexahydrocoumarin derivatives were synthesized by one-pot multicomponent reaction of Meldrum’s acid with benzaldehyde, and cyclohexanedione in glycerol. Compared to classic methods, this method has the advantages of milder reaction conditions, good yields, easy processing and environmental benignity.

Based on the Cloud-P2P storage architecture, taking into account the data access mechanism with both the data center and the peer-based layer, considering the repair process of the replica, a three-dimensional Markov chain model was constructed. The steady-state analysis of the model is obtained by using a matrix-geometric method. Then, the per-formance measures in terms of peer-based traffic load, the average access time, and the repair rate are given. Moreover, numerical results with analysis and simulation are provided to demonstrate the influence of the system parameters on the system performance. By constructing a benefit function, the number of replicas in peer-based layer is optimized.

Andrias davidianus ranavirus (ADRV) is an emerging viral pathogen that causes severe systemic hemorrhagic disease in Chinese giant salamanders. There is an urgent need for developing an effective vaccine against this fatal disease. In this study, DNA vaccines containing the ADRV 2L gene (pcDNA-2L) and the 58L gene (pcDNA-58L) were respectively constructed, and their immune protective effects were evaluated in Chinese giant salamanders. In vitro and in vivo expression of the vaccine plasmids were confirmed in transfected cells and muscle tissues of vaccinated Chinese giant salamanders by using immunoblot analysis or RT-PCR. Following ADRV challenge, the Chinese giant salamanders vaccinated with pcDNA-2L showed a relative percent survival (RPS) of 66.7%, which was significant higher than that in Chinese giant salamanders immunized with pcDNA-58L (RPS of 3.3%). Moreover, the specific antibody against ADRV was detected in Chinese giant salamanders vaccinated with pcDNA-2L at 14 and 21 days post-vaccination by indirect enzyme-linked immunosorbent assay (ELISA). Transcriptional analysis revealed that the expression levels of immune-related genes including type I interferon (IFN), myxovirus resistance (Mx), major histocompatibility complex class IA (MHC IA), and immunoglobulin M (IgM) were strongly up-regulated after vaccination with pcDNA-2L. Furthermore, vaccination with pcDNA-2L significantly suppressed the virus replication, which was seen by a low viral load in the spleen of Chinese giant salamander survivals after ADRV challenge. These results indicated that pcDNA-2L could induce a significant innate immune response and an adaptive immune response involving both humoral and cell-mediated immunity that conferred effective protection against ADRV infection, and might be a potential vaccine candidate for controlling ADRV disease in Chinese giant salamanders.

A method was developed for the simultaneous analysis of trace arsine and phosphine in ethylene and propylene products by gas chromatography-atomic emission spectroscopy detector and the chromatographic analysis conditions were optimized, and the detection limit, linear range, recovery rate and repeatability of the method were investigated. The results showed that the detection limit of the method for arsine was as low as 0.02 mL/m3, the linear correlation coefficient was more than 0.999 in the volume concentration range of 0.02~2 090 mL/m3, the recovery rate was 87.60% and the relative standard deviation of the 3 parallel measurements was 1.83%. The detection limit of phosphine was as low as 0.03 mL/m3, the correlation coefficient was greater than 0.999 in the volume concentration range of 0.03~3 010 mL/m3, the recovery rate was 106.13% and the relative standard deviation of the 3 parallel measurements was 3.39%. The method can be used as a control analysis method for trace arsine and phosphine in ethylene and propylene products.