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Core structural materials such as cladding in advanced nuclear reactors face harsh service environments such as high-temperature, and their comprehensive performance is one of the bottlenecks restricting the development of advanced reactors. Mo and its alloys are key candidate, but pure Mo suffers from a lack of high-temperature strength. Mo-based alloys are superior to pure Mo in terms of mechanical properties. Research found that the addition of a certain amount of Re, W, Ti, Zr, C and other elements will enhance the high-temperature strength of Mo-based alloys. The effects produced by the ingredients are very complex and cannot be found in great detail by testing. Now materials genetic engineering, based on the prediction of data-driven material properties and optimization, shortening the cycle of materials research and development, and thus speed up the process of the entire field. Thus a CNN regression model based on Bayesian optimization was constructed based on the data obtained from literature research and preliminary experiment. The collected Mo-based alloy dataset contained 220 samples and 38 compositions as well as test temperature characteristics of tensile with the target variable being tensile strength. Found that the Re, C, O, N, Ti, Zr, Nb, La, W, Hf, Ta, Si, and Ni have a higher weight on the target value, and C, Ti, and Zr positively affect the tensile strength. Re, O, N, La, W, Hf, Ta, Si, and N have a negative tendency to correlate the characteristics with the tensile strength. Using the R2 value as an evaluation metric, the model is able to achieve 0.832 6. Combined with correlation analysis and modeling prediction analysis, it is concluded that Ti, Zr, Re and La2O3 are beneficial to the enhancement of high-temperature tensile strength of Mo-based alloy. N and Si are not conducive to the enhancement of tensile strength of Mo-based alloy at high-temperature. According to the correlation analysis conclusion, the effect of the coupling of these compositions C-Zr, Nb-Hf-Ta, Ni-Si, N-O and Zr-Ti on the tensile properties of the materials at high-temperatures will be considered subsequently, along with the simultaneous enhancement of toughness. Subsequently, by analyzing the influence of the combination of two elements or three elements on the change of tensile strength, it can get the composition design scheme that the tensile strength of Mo-based alloy reaches a certain range under specific temperature conditions.

Pandemic (H1N1) 2009 virus emerged in March 2009 and spread worldwide (1,2). Most patient laboratory data result from samples or information obtained on the day of hospitalization or when the [...]

Objective: To understand the hemagglutination inhibition antibody level in patients with influenza A H1N1., Methods: Sera from 28 patients with influenza A H1N1 at different time points after illness onset were collected and measured by hemagglutination inhibition assay., Results: The serum hemagglutination inhibition antibody titers at 1, 5, 15, 22, 37, 49 and 58 days after illness onset were 5.36, 9.39, 39.02, 57.99, 137.92, 55.19 and 57.99 respectively. The top geometric mean titer of hemagglutination inhibition antibody was 148.55. The antibody seroconversion rate and seroprotection rate were occurred in 96.4% (27/28) of patients., Conclusion: The patients with influenza A H1N1 have effective immune response.

Objective: To construct the recombinant plasmid containing S1 gene of new type of reovirus, and to study the expression of protein sigma1 in Vero cells., Methods: The recombinant plasmid, named pC-S, was constructed by cloning S1 gene into vector pCAGGS/MCS. Then Vero cells were transfected with pC-S and collected at 24, 48, 72 h post transfection followed by SDS-PAGE and Western-Blot assay., Results: Results both SDS-PAGE and Western-Blot assay indicated that sigma1 protein could be expressed well and the highest expression level was 72 h post transfection., Conclusions: Sigma1 protein could be expressed well in Vero cells by transfected with recombinant plasmid containing S1 gene, and could give some implications for subsequent research on virus-host interactions.

Aim: To develop a coxsackievirus A16 (Cox A16) VP1 gene plasmid which delivered by live attenuated Salmonella., Methods: The plasmid which expressed VP1 protein of CoxA16 was constructed by gene recombination. Cellular expression was assessed by Western bloten analysis. Then the recombinant attenuated Salmonella which harboring the plasmid were constructed by electro transformation., Results: CoxA16 VP1 gene sequence was inserted into a eukaryotic expression plasmid. VP1 protein was detected in the culture supernatant., Conclusion: The plasmid is constructed successfully and it can be expressed effectively in vitro. The recombinant bacteria are constructed successfully. This has provided a basis for further research of an oral CoxA16 vaccine.

Objective: To develop a system to rescue virus by intracellular expression of T7 RNA Polymerase., Methods: The gene of T7 RNA Polymerase was amplified and cloned to VR1012 by molecular biological technology. The expression plasmid VR-1a was then identified. VR-1a and EV71 infectious plasmid were co-transfected in Vero cell. CPE was observed and viral gene viral antigen were detected., Results: The gene of T7 RNA Polymerase was successfully cloned into vector VR1012. Vero cell developed to CPE after being transfected VR-1a and EV71 infectious plasmid. EV71 gene was amplified by RT-PCR from the culture. EV71 antigen was also detected by ELISA., Conclusion: The method can be used to rescue virus. It could apply to immunologic research of EV71 DNA vaccine.

Objective: To develop attenuated Salmonella which harboring enterovirus 71 (EV71) VP1 gene., Methods: The plasmid which expressed VP1 protein of EV71 was constructed by gene recombination. Cellular expression was assessed by Western Blot analysis. The recombinant plasmid was then transformed into attenuated Salmonella SL7207., Results: EV71 VP1 gene sequence was inserted into a eukaryotic expression plasmid VR1012. VP1 protein was detected by Western Blot analysis in the culture supernatant. And the attenuated Salmonella harbored the plasmid stable., Conclusion: The plasmid was constructed successfully and it can express effectively in vitro. The bacteria which harboring the plasmid were constructed successfully. This has provided a basis for further research of an oral EV71 vaccine.

Objective: To develop a vector inserted with complete genome of poliovirus strain Sabin I., Methods: The 3 fragments of the complete genome of Sabin I was amplified and cloned to pEASY-T3 by molecular biological technology. These cloned pEASY-T3 were then digested by Restriction enzymes and ligated to pWSK29 step by step and identified., Results: The complete genome of poliovirus strain Sabin I was successfully cloned into vector pWSK29 with 9 nucleotide mutations., Conclusion: The complete genome plasmid was constructed and it provided a basis for further research of the function of Sabin I.

Objective: To develop a coexpression plasmid which expressing envelope protein and nucleoprotein of hepatitis B virus and know of its expressing efficiency., Methods: The plasmid coexpressing envelope protein and nucleoprotein of hepatitis B virus under the CMV promoter respectively was constructed by gene recombination. Cellular expression was assessed by ELISA., Results: Multiple cloning site was inserted into expression vector contain hepatitis B virus PreS2-S gene. And expression unit containing hepatitis B virus PreC-C was cloned into it. HBsAg and HBeAg was detected both in the culture supernatant and in the cells., Conclusion: The coexpressing plasmid was constructed successfully and it can express effectively in vitro. This has provided a basis for further research of the therapeutic HBV DNA vaccine.

Objective: To understand the level and clinical significance of soluble CD40 in patients with chronic hepatitis B., Methods: Detecting the concentration of sCD40 from 176 cases with chronic hepatitis B by ELISA and analyzing its relationship with different grades of inflammation and necrosis in liver tissue., Results: sCD40 from patients with chronic hepatitis B was significantly higher than those from healthy. And that the concentration of sCD40 was positive correlation with severe clinical disease and liver inflammation and necrosis. In patients whose ALT lower than 80 IU/L and sCD40 higher than 80 pg/ml, it showed that 65.85% cases have high grade of liver inflammation and necrosis, which was significantly higher than patients with sCD40 lower than 80 pg/ ml., Conclusion: The concentration of sCD40 is positively related with the grade of liver inflammation and necrosis. This information could help us to evaluate the status of chronic hepatitis B as an immunological index.

Objective: To demonstrate molecular characterization of a newly isolated enterovirus., Methods: Virus were isolated from patient with unknown-causing disease and tested by reverse transcription-polymerase chain reaction (RT-PCR) and 5'3'RACE (rapid amplification of cDNA ends, RACE), in an attempt to obtain the sequence of this newly isolated enterovirus., Results: Sequence analysis showed that this newly isolated enterovirus shared 83%-94% nucleotide identity and 91%-100% amino acid identity with enterovirus 89. Phylogenetic analysis indicated that it was probably a new subtype of enterovirus 89., Conclusion: This newly isolated enterovirus in the stool specimen from patient has the same serotype with enterovirus 89, but it was probably a new subtype of enterovirus 89.