饲料营养免疫对非洲猪瘟防控的作用

非洲猪瘟疫情的暴发对我国养猪产业造成了严重影响。尽管农业部门、科研专家和养猪工作者通过提高生物安全手段防控非洲猪瘟,对恢复我国生猪养殖数量和猪肉自给能力取得了相应效果,但随之而来的是猪群应激增加、饲料营养的有效性降低和猪群抗病力降低等问题。文章结合非洲猪瘟病毒特点和防控现状等,从饲料营养免疫的视角,分析如何减少猪群应激和提升猪群免疫力,以期为非洲猪瘟的综合防控提供思路。

Sufficient conditions of the various stabilities of the linear time-varying delayed differential equations

Due to the appearance and the study of the ornithopter and flexible-wing micro air vehicles, etc., the time-varying systems become more and more important and ubiquitous in the study of the mechanics. In this letter, the sufficient conditions of the uniform asymptotic stability are first presented for the delayed time-varying linear differential equations with any time delay by employing the Dini derivative, Lozinskii measure and the generalized scalar Halanay delayed differential inequality. They are especially based on the estimation of the arbitrary solutions but not the fundamental solution matrix since their solutions＇ space is infinite-dimensional. Then some sufficient conditions of the stability, asymptotic stability and uniform asymptotic stability of the delayed time-varying linear system with a sufficiently small time delay are reported by employing Taylor expansion and Dini derivative. It implies that these stabilities can be guaranteed by the Lozinskii measure of the matrix composing of the time delay and the coefficient matrices of the system.

Incidence of Macrosomia in Rural Areas—Henan Province,China,2013–2017

Introduction:Macrosomia has short-term and long-term adverse health effects and is thus an important public health concern.Recent decades have witnessed increasing incidence of macrosomia in many countries.Methods:The present study used a large population-based birth cohort study to depict incidence of macrosomia among live births in rural areas of Henan Province of China from 2013 to 2017.Results:Among the 1,262,916 births,82,353 were cases of macrosomia.The overall incidence of all types of macrosomia,of macrosomia with birth weight<4,500 g,and of macrosomia with birth weight≥4,500 g were 6.52%,5.30%,and 1.22%,respectively.From 2013 to 2017,the incidence of macrosomia decreased by 31.3%from 7.96%in 2013 to 5.47%in 2017(X^(2)_(trend)=946.96,P_(trend)<0.001).Male infants and infants≥42 gestational weeks had significantly higher incidence of macrosomia than that of female infants and infants<42 gestational weeks(P<0.001).Conclusion:Gestational weight control through nutrition management and physical activities during pregnancy are needed to reduce incidence of macrosomia.

Trends of Adverse Pregnancy Outcomes in a High Prevalence Region of Birth Defects——Shanxi Province,China,2007-2019

Summary What is already known about this topic?Shanxi Province in northern China has been identified as a region with the highest prevalence of birth defects nationwide.With large amounts of financial support devoted for prevention and related interventions for birth defects,huge progress has been made as a 60% decrease in its prevalence was observed from 2009 to 2014.

Measuring the Effect of COVID-19 Pandemic on Mortality:Review and Prospect--China,2021

Current progress in measuring the effect of the pandemic on mortality is limited.Few studies have comprehensively and systematically elucidated the mechanism through which the pandemic affects mortality and what indicators are valid to capture such an effect.This paper presents a comprehensive analysis regarding the multifaceted effects of coronavirus disease 2019(COVID-19)on mortality and its measurements[i.e.,confirmed deaths per million people(CDPMP),case fatality rate(CFR),infection fatality risk(IFR),excess mortality P-score(EMPS),and life expectancy(LE)].It was revealed that both data collection efforts and measurements on mortality due to COVID-19 were far from perfect and discussed the importance of accurate,prompt,and accessible data by any government over the course of fighting against the COVID-19 pandemic.It is believed that the biggest challenge in measuring the effect of the COVID-19 pandemic on mortality lies not in the construction of indicators at the academic level,but in the collection of data at the practical level.Thus,it is suggested to take measures to better monitor the development of the pandemic and mitigate the increasing burdens borne by the public health systems by improving the tracking system of mortality,standardizing the diagnosis of COVID-19’s deaths,and disclosing mortality data.

Trends in the Prevalence of Cognitive Impairment Among Older Adults Aged 65 to 105 Years—China,2002–2018

Introduction:This study aims to analyze trends and subgroup differences in the prevalence of cognitive impairment among older Chinese adults aged 65–105 years from 2002 to 2018.Methods:Data were drawn from six waves of the Chinese Longitudinal Healthy Longevity Survey(CLHLS).Cognitive function was measured using the Chinese version of the Mini-Mental State Examination(CMMSE).Cognitive impairment was determined by the total CMMSE score and educational attainment of participants.The generalized estimating equation(GEE)models with a logistic link and binominal distribution were performed to assess the secular trend in the prevalence.Results:The prevalence of cognitive impairment among older adults aged 65–105 years decreased from 3.44%[95%confidence interval(CI):3.15%–3.73%]in 2002 to 2.41%(95%CI:2.17%–2.65%)in 2018 in China.The prevalence was slightly higher in women than in men in 2002(3.71%vs.3.13%,P<0.05),and there was no significant difference between women and men in 2018(2.60%vs.2.21%,P=0.12).Rural older adults had a higher prevalence of cognitive impairment before 2014,but their urban counterparts had a higher prevalence in 2018(2.75%vs.2.06%,P<0.05).The GEE regression model showed that each successive year was associated with a 3%reduction in the odds of the prevalence of cognitive impairment[odds ratio(OR)=0.97;95%CI:0.97–0.97;P<0.05].Conclusions:The prevalence of cognitive impairment among Chinese older adults aged 65–105 years declined slowly from 2002 to 2018.The gender,urban-rural,age,and regional differences in the prevalence of cognitive impairment changed over time.

Adverse Childhood Experiences and Depressive Symptoms Trajectories Among Middle-Aged and Elderly—China,2011–2018

Summary What is already known about this topic?Previous studies in western populations have found consistent relationships between adverse childhood experiences and the development of mood and anxiety disorders,especially depressive symptoms in adolescence and adulthood.What is added by this report?This study used a longitudinal design and analytic method to model depressive symptom trajectories from 2011 to 2018 among the middle-aged and elderly in China.This study also investigated the association between adverse childhood experiences and adulthood depressive symptoms in the Chinese population.What are the implications for public health practice?Future public policy could consider early prevention and intervention on adverse childhood experiences to prevent adult depressive symptoms.Besides,it is essential to create safe,stable,and nurturing environments for children’s development.