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Using game theory to optimize honeypot behavior is an important method in improving defender's trapping ability. Existing work tends to use over simplified action spaces and consider isolated game stages. A game model named HoneyED with expanded action spaces and covering comprehensively the whole interaction process between a honeypot and its adversary was proposed. The model was focused on the change in the attacker's beliefs about its opponent's real identity. A pure-strategy-equilibrium involving belief was established for the model by theoretical analysis. Then, based on the idea of deep counterfactual regret minimization (Deep-CFR), an optimization algorithm was designed to find an approximate hybrid-strategy-equilibrium. Agents for both sides following hybrid strategies from the approximate equilibrium were obtained. Theoretical and experimental results show that the attacker should quit the game when its belief reaches a certain threshold for maximizing its payoff. But the defender's strategy is able to maximize the honeypot's profit by reducing the attacker's belief to extend its stay as long as possible and by selecting the most suitable response to attackers with different deception recognition abilities. [ABSTRACT FROM AUTHOR]

There is usually a reconnaissance stage before a network attack, the attacker obtains the key information of the target system through techniques such as traffic analysis and active scanning, to formulate a targeted network attack. Deception defense techniques based on network characteristics obfuscation is an effective strategy to confront network reconnaissance, which makes the attacker launch an ineffective attack by thwarting the attacker's reconnaissance stage. The technical principle of the existing obfuscation defense solutions was analyzed, the formal definition of network obfuscation was given, the existing research works were discussed from three aspects, and finally the development trend of the obfuscation deception defense technique were analyzed. [ABSTRACT FROM AUTHOR]

The torque of magnetic couplers can be transferred by utilizing the magnetic field coupling,which changes the rigid connection into non-contact soft connection. It has the advantages of soft starting,vibration reduction,locked-rotor protection,high reliability,and is applied in industry. The magnetic couplers can also be used in specific conditions,such as superconducting flywheel energy storage system（ SFESS）,which can realize the motor placed out of vacuum chamber with no need for stator cooling system,the completely dynamic sealing of vacuum chamber,and long time energy storage. Due to rare application and research in the condition of high speed for magnetic couplers,the transfer characteristics at high speed of asynchronous axial magnetic coupler is studied based on the application of SFESS. The finite element model is built by using the general simulation method based on slip speed,the performance parameters of transferred torque,axial force,and magnetic flux density in the air-gap are calculated,and the temperature rise characteristic of critical components is analyzed. The prototype is manufactured,and the test platform of transfer characteristics at high speed is established. The experiments are conducted at the synchronous speed 9 500 r/min and the conventional modeling method is validated by comparing the experimental results with simulated results. Also the torque transfer characteristic at various speeds is compared. The feasibility of asynchronous axial magnetic coupler for high speed application is validated.

Objectives: To understand the awareness rate and its influencing factors of their HBV infection status among HBsAg-positive persons aged 15-69 years in China. Methods: A cross-sectional design was used to conduct a questionnaire survey on the awareness of their infection status among HBsAg-positive persons aged 15-69 years who were identified in the 2020 national hepatitis B seroepidemiology survey. The awareness rate of the whole respondent and respondents with different characteristics were described, and the differences were compared with the χ 2 test. The logistic regression model was used to analyze the factors influencing the awareness rate. Results: The overall awareness rate among the respondents was 43.10% (1 828/4 241). The awareness rate was lower in males than in females (41.30% vs. 44.65%). The awareness rate was lower in the 60-69-years-old age group than in other age groups (30.38% vs. 36.77%-57.58%). The awareness rate was lower in rural areas than in urban areas (39.43% vs. 47.32%). The awareness rate was lower in regions with a per capita gross domestic product (GDP) below RMB 54 000 than in regions with a per capita GDP of RMB 54 000 and above (36.81% vs. 41.61%-50.30%). The awareness rate was lower in respondents without other liver diseases than with other liver diseases (41.52% vs. 60.68%). The awareness rate was lower in respondents without a family history of hepatitis B-related disease or unknown family history than with a family history (43.58% vs. 68.26%; 24.71% vs. 68.26%). Multivariate logistic regression analysis showed that male [odds ratio ( OR )=0.841, 95% confidence interval ( CI) : 0.734-0.964], high school and below [primary school and below, junior middle school, high school/technical secondary school, OR (95% CI ): 0.247 (0.190-0.321), 0.451 (0.352-0.577), 0.634 (0.486-0.827)], rural areas ( OR =0.822, 95% CI : 0.715-0.945) and regions with a per capita GDP below RMB 80 000 [54 000-80 000, OR (95% CI ): 0.810 (0.688-0.954), below RMB 54 000, OR (95% CI ): 0.793 (0.669-0.941)] were the negative factors influencing the awareness rate. While 30-39-years-old ( OR =2.089, 95% CI : 1.626-2.683) and 40-49-years-old ( OR =1.590, 95% CI : 1.250-2.023) age groups, with other liver diseases ( OR =2.244, 95% CI : 1.754-2.871) and family history related to hepatitis B ( OR =2.688, 95% CI : 2.242-3.223) were the positive factors influencing the awareness rate. Conclusion: The overall awareness rate of their infection status among HBsAg-positive persons aged 15-69 years is 43.10% in China. Health promotion and coverage expansion on HBV screening should be further strengthened to achieve the proposed World Health Organization's target of 90% HBV infection diagnosis rate by 2030.

Objective: To examine the influence of three-booster-doses hepatitis B vaccines on children with normal and high antibody response to primary vaccination., Methods: Antibody against hepatitis B surface antigen (anti-HBs) were detected after primary vaccination and children with normal or high response to hepatitis B primary vaccination at infancy, were identified. Children who were given three booster doses were selected to form the booster group and who were given no booster dose were 1∶1 matched with the same gender and residence to form the control group. Blood samples were obtained from all the participants and tested for anti-HBs and anti-HBc, 5 years after the primary vaccination., Results: The positive rates of anti-HBs response to primary vaccination were 97.39% (224/230, 95% CI: 94.41%-99.04%) in the booster group and 53.91% (124/230, 95% CI: 47.24%-60.48%) in the control group (P<0.05), 5 years after the primary vaccination. Geometric mean concentration (GMC) of anti-HBs were 1 140.02 (887.46-1 464.46) mIU/ml in the booster group and 11.53 (8.73-15.23) mIU/ml in the control group (P<0.05). The prevalence rates of breakthrough HBV infection were 0.87% (2/230) in the booster group and 2.17%(5/230) in the control group (P>0.05). RESULTS from the multivariable analysis showed that the booster doses (OR=38.75, 95%CI: 16.23-92.54) and the level of anti-HBs after the primary vaccination (OR =3.06, 95%CI:1.51-6.17) were independently associated with the positive rates of anti-HBs, 5 years after the primary vaccination (P<0.05)., Conclusion: Programs with three booster doses to children that showing normal and high antibody response to primary vaccination could improve the persistence of anti-HBs but possibly would not be able to prevent the HBV infection.

Objective: To analyze the characteristics of health-seeking behaviors and related influencing factors of the community-based hepatitis B surface antigen (HBsAg) positive adults, in China., Methods: Based on the cohort formed by the HBsAg positive patients, in the national sero-survey project in 2006, we conducted a follow-up programs in 2010 and 2014. In the latest follow-up project, we carried out a cross-sectional study to collect information on health-seeking behaviors of the patients. Questionnaires would include information on clinic visits, diagnosis, regular physical examination and treatments,etc. We used the SPSS 18.0 software for data analysis., Results: Totally, 2 478 HBsAg positive adults (≥18 years old) were followed through, with 34.4% (853/2 478) of them had visited the doctors and diagnosed after they were informed the status of HBsAg positivity, in the 2006-sero-survey program. Among patients who ever visiting the clinic, 51.2% (372/727) of them underwent at least medical examination once a year, with 31.5% (229/727) of them received treatment. Furthermore, 34.5% (79/229) of the treated patients adopted the traditional Chinese medicine or medicine for ' liver protection'. 56.8% (130/229) of the treated patients received antiviral drugs. Data from the binary logistic regression showed that the major influencing factors on clinic visits would include: age, level of education received and residencial areas (rural/urban)., Conclusions: Consciousness on health was low in those community-based HBsAg positive people. Standerdized management and clinical treatment programs should be set up accordingly.

We wished to undertake molecular genetic typing and evaluate recombinants of the hepatitis-B virus (HBV) in Tibet (China). Multistage random sampling was used to collect HBsAg-positive samples. Nested polymerase chain reactions were used to amplify the whole sequence of the HBV. DNAstar, MEGA6 and SimPlot were used to assemble sequences, create phylogenetic trees, and undertake recombination analyses. Twelve whole sequences of the HBV of a Tibetan population were collected using these methods. Results showed that all 12 strains were C/D recombinants. Nine of the recombinations were at nt750, and the other three at nt1526. Therefore, the 12 strains could be divided into two types of recombinants: C/Da and C/Db. Analyses of the sequence of the whole genome revealed that the 12 strains belonged to genotype C, and that the nucleotide distance was > 4% between the 12 strains and sub-genotypes C1 to C15 in Genbank. The most likely sub-genotype was C1. Individuals with C/Da were from central and northern Tibet (e.g., Lasa, Linzhi, Ali) and those with C/Db recombinants were from Shannan in southern Tibet. These data suggest that the two types of recombinants had a good distribution in Tibet. Also, they can provide important information for studies on HBV recombination, gene features, virus evolution, as well as the control and prevention of HBV infection in Tibet.

Objective: To examine the immune memory status to hepatitis B vaccine among infants with normal or high antibody response to primary vaccination, 5 years after the primary vaccination and the risk factors associated with the immune memory., Methods: Titers of the antibody against hepatitis B surface antigen (anti-HBs) were detected, five years after the primary vaccination among children who appeared normal or high response to hepatitis B primary vaccination in infancy. Those whose anti-HBs titers were low than protective level (10 mIU/ml) were given a challenge dose of hepatitis B vaccine and titers of anti-HBs were detected 14 days after the challenge. Positive rate and geometric mean titer (GMT) of anti-HBs were calculated. Level of the anti-HBs titers after primary vaccination, at following-up and after the challenge periods were divided into different levels, respectively. Risk factors associated with the levels of anti-HBs titer after the challenge were examined by univariate analysis that and multivariable analysis., Results: Anti-HBs waned to the level below protective standard among 37.98% of the children with normal or high antibody response to hepatitis B primary vaccination; among those children whose anti-HBs were below the protection standard. The seroconversion rate and GMT of anti-HBs after the challenge dose were 98.95% (757/765) and 2 811.69 mIU/ml [95% Confidence Interval (CI) :2 513.55-3 145.19 mIU/ml] , respectively. Titers and levels of anti-HBs after the challenge, appeared an increase with anti-HBs after primary vaccination and the anti-HBs in the following-up (F=5.46, 10.23 respectively; P<0.000 1 for both) periods. Results from the multivariable analysis showed that gender, premature birth and birth weight were factors insignificantly associated with the anti-HBs titers after the dose of challenge, while the anti-HBs levels were independently associated with the levels of anti-HBs titer after the challenge [OR = 1.001 (95%CI: 1.000-1.002) , P<0.001; OR=1.28 (95%CI: 1.81-1.39) , P<0.001]at the following-up periods., Conclusions: Strong immune memory could be found among those children with normal or high responses to hepatitis B vaccination, 5 years after the primary vaccination. The intensity of immune memory might be associated with the anti-HBs titer after primary vaccination as well as the anti-HBs titers before the challenge dose was given.

Objective: To analyze the information of the supplementary card for hepatitis B and the laboratory confirmed result of immunoglobulin M antibody to hepatitis B virus (HBV) Core Antigen (anti-HBc IgM) for the suspected acute hepatitis B to evaluate the hepatitis B report data on pilot surveillance., Methods: 200 counties were established in China for hepatitis B pilot surveillance and 63 641 cases were reported. We added a supplementary card in National Notificable Disease Reporting System (NNDRS) and all the reported hepatitis B cases in NNDRS were required to fill the supplementary card. Venous blood 5 ml was collected and a confirmed test of anti-HBc IgM was made for suspected acute hepatitis B. We made confirmed diagnosis for the suspected acute hepatitis B according to the supplementary card information of the reporting card and the confirmed test result of anti-HBc IgM., Results: 63 641 hepatitis B cases were reported in 200 hepatitis B pilot surveillance counties in 2013. Among 1 723 cases which were filled with the HBsAg positive within six months in supplementary card, 735 cases were reported as chronic hepatitis B, the proportion was 42.66%. Among 4 582 cases which were filled with anti-HBc IgM positive in supplementary card, 2 436 cases were reported as acute hepatitis B, the proportion was 53.16%. 1 829 cases were reported as chronic hepatitis B, the proportion was 39.92%. The validity cases of the information for liver puncture and the HBV surface antigen (HBsAg) transform during the recovery period in supplementary cards for all the reporting cases were 579 and 4 961, and the rate were 0.91% and 7.80%, respectively. 4 302 suspected acute cases were made confirmed diagnosis, and 1 197 cases (27.82%) were confirmed acute and 2 590 cases (60.20%) were confirmed chronic., Conclusion: Clinical doctors failed to make full use of the information of supplementary cards to make classification diagnose for hepatitis B. Suspected acute hepatitis B with anti-HBc IgM positive should be pay attention to follow up and further distinguish acute or chronic hepatitis B according to the HBsAg transform.

Induced pluripotent stem cells (iPSCs) were reprogrammed from somatic cells using specific transcription factors. Bypassing the ethical issue caused by embryonic stem cells (ESCs), iPSCs can be successfully induced from a variety of cells, which makes iPSCs a powerful research tool for developmental biology. iPSCs have also become indispensable to the research of life science due to their broad potential applications. However, it's a big challenge to obtain iPSCs with high quality and genetic stability. Here, we review the research progress of increasing the reprogramming mechanism and genetic stability of iPSCs in order to provide references of reprogramming efficiency of iPSCs, reducing the cost, and addressing key points of iPSCs quality control, further promoting clinical application of the iPSCs.