Modeling the Long-term Antibody Response and Duration of Immune Protection Induced by an Inactivated,Preservative-free Hepatitis A Vaccine(Healive)in Children

Objective Long-term seroprotection via the hepatitis A vaccine is essential for the prevention of disease from the hepatitis A virus(HAV).Due to documented difficulties during decade-long follow-ups after receiving vaccines,statistical-modeling approaches have been applied to predict the duration of immune protection.Methods Based on five-year follow-up data from a randomized positive-controlled trial among Chinese children(1–8 years old)following a 0,6 months vaccination schedule,a power-law model accounting for the kinetics of B-cell turnover,as well as a modified power-law model considering a memory-B-cell subpopulation,were fitted to predict the long-term immune responses induced by HAV vaccination(Healive or Havrix).Anti-HAV levels of each individual and seroconversion rates up to 30 years after vaccination were predicted.Results A total of 375 participants who completed the two-dose vaccination were included in the analysis.Both models predicted that,over a life-long period,participants vaccinated with Healive would have close but slightly higher antibody titers than those of participants vaccinated with Havrix.Additionally,consistent with previous studies,more than 90%of participants were predicted to maintain seroconversion for at least 30 years.Moreover,the modified power-law model predicted that the antibody titers would reach a plateau level after nearly 15 years post-vaccination.Conclusions Based on the results of our modeling,Healive may adequately induce long-term immune responses following a 0,6 months vaccination schedule in children via induction of memory B cells to provide stable and durable immune protection.

Construction and application of Markov model for followup data

Objective: To construct Markov model for clinical follow up data and predict the number of survivals and deaths. Methods: The state of patients was classified into survival. death and censorship. The weighted least squares method was used for estimating parameters. Results: Markov model for survival analysis of follow--up data was presented. By using an example, the transition probability matrices were obtained and the number of survivals and deaths at each observation point was predicted respectively. Conclusion: Markov model constructed in the present study to analyze clinical follow up data could be used as effective supplemention for life table analysis.

Jidong cognitive impairment cohort study: objectives, design, and baseline screening

The risk of dementia increases in patients with cognitive impairment.However,it is not clear what factors contribute to the onset of dementia in those with cognitive impairment.In this prospective cohort study,we will investigate the every-five-year incidence of cognitive impairment and prognostic factors for cognitive impairment.The Jidong cognitive impairment cohort was established from April 2012 to August 2015,during which we recruited 5854 healthy participants(55.1%male)older than 45 years(mean,57 years).Participants received a health examination in the Staff Hospital,Jidong Oilfield Branch,China National Petroleum Corporation.Baseline data and blood samples were collected.Cognitive impairment was evaluated using the Mini-Mental State Examination,and was defined as a Mini-Mental State Examination score of less than 24.Dementia was assessed using the criteria of Diagnostic and Statistical Manual of Mental Disorders(Fourth edition),the International Working Group criteria,and the Mini-Mental State Examination score.The follow-up will continue until December 2024,during which a prognostic model will be constructed.The primary outcome is the presence/absence of dementia and the secondary outcome is quality of life.Baseline screening results showed the following:(1)Cognitive impairment was apparent in 320 participants(5.5%).These participants will be excluded from the Jidong cohort study,and the remaining participants will be followed up.(2)Of the 320 participants with cognitive impairment,there was a significantly higher prevalence of illiteracy than other education levels(35.9%,P<0.05).Age,arterial hypertension,alcohol consumption,and passive smoking differed significantly between the cognitive impairment and healthy groups(P<0.05).Multivariate logistic regression models showed that age(odds ratio[OR]=1.059,95%confidence interval[CI]:1.044-1.074)and arterial hypertension(OR=1.665,95%CI:1.143-2.427)were risk factors for mild cognitive impairment.With the increase of educational level(illiteracy,primary school,junior high school,high school,university,and above),cognitive impairment gradually decreased(OR<1,P<0.05).(3)This cohort study has initially screened for several risk factors for cognitive impairment at baseline,and subsequent prospective data will further describe,validate,and evaluate the effects of these risk factors on cognitive impairment and dementia.These results can provide clinical evidence for the early prevention of cognitive impairment and dementia.The study was approved by the Ethics Committee of Kailuan General Hospital of Tangshan City and the Medical Ethics Committee,Staff Hospital,Jidong Oilfield Branch,China National Petroleum Corporation on July 12,2013(approval No.2013 YILUNZI 1).

Tax and Fee Burden of Rural Households and Economic Growth in China

This paper is based on the fixed follow-up observation data of the countryside in Shanxi and Zhejiang provinces of china. It gives positive analysis of the tax and fee burden of rural households in these two provinces as weU as the tendency of its development since the mid-1980s. It is found from the analysis that the model of tax and fee burden is completely different between these two provinces and each model brings quite different effects. In the Shanxi burden model focusing on the collection of fees, farmers pay less taxes and fees, but they have to pay more compared with their income, thus resulting in a lack of the stamina for rural household economy even causing the economy to be thrown into a state of stagnancy. In the Zhejiang burden model focusing on tax, farmers pay more tax, but its percentage is lower compared with their income, with the result that the rural household economy has a strong stamina for growth. With the coming system of ＂transforming fees into taxes＂ to be trial-implemented in the rural areas, the pilot experience in Anhui Province is truly important, but comparatively speaking, the practice in Zhejiang is of more immediate significance.

英语专业继续教育的教学改革

There has been an increased demand for qualifiedteachers and the consequent need to train these teachers wlth the development of economy.The last fiveyears have witnessed the significance of in-serviceteacher training.However,quite a lot of in-serviceteacher training focuses are laid on English languageimprovement,content rather than process is empha-sized.That is,I think,not in accordance with the na-