Prevalence of Autism Spectrum Disorder in China:A Nationwide Multi-center Population-based Study Among Children Aged 6 to 12 Years

This study aimed to obtain the first national estimate of the prevalence of autism spectrum disorder(ASD) in Chinese children.We targeted the population of 6 to 12-year-old children for this prevalence study by multistage convenient cluster sampling.The Modified Chinese Autism Spectrum Rating Scale was used for the screening process.Of the target population of 142,086 children,88.5%(n=125,806) participated in the study.A total of 363 children were confirmed as having ASD.The observed ASD prevalence rate was 0.29%(95% CI:0.26%-0.32%) for the overall population.After adjustment for response rates,the estimated number of ASD cases was867 in the target population sample,thereby achieving an estimated prevalence of 0.70%(95% CI:0.64%-0.74%).The prevalence was significantly higher in boys than in girls(0.95%;95% CI:0.87%-1.02% versus 0.30%;95%CI:0.26%-0.34%;P <0.001).Of the 363 confirmed ASD cases,43.3% were newly diagnosed,and most of those(90.4%) were attending regular schools,and 68.8% of the children with ASD had at least one neuropsychiatric comorbidity.Our findings provide reliable data on the estimated ASD prevalence and comorbidities in Chinese children.

Comparison of biochar properties from 5 kinds of halophyte produced by slow pyrolysis at 500℃

Glycophyte biomass-derived biochars are currently concerned in most studies.However,little attention is given to the char-acteristics of halophyte-derived biochars.In this study,five typical halophytes of euhalophytes(Suaeda altissima,Suaeda salsa,and Kalidium foliatum),recretohalophytes(Phragmites australis),and pseudohalophytes(Tamarix chinensis)which are widely distributed in the arid and semiarid regions of northwestern China were selected for producing biochars with a slow pyrolysis process at 500℃for 1 h.The harvested biochars were characterized in elemental content,pores,surface area,and surface charges,and then their potential value as a soil conditioner was evaluated.The results showed that the halophyte-derived biochars had variable ash and Na+contents,ranging from 7.26 to 23.64%and 1.06 to 33.93 g kg^(−1)respectively.The EC value of the biochars ranged from 1.76 to 23.45 mS cm^(−1).The biochar derived from Suaeda altissima had a very low specific surface area(SSA),3.50 m^(2)g^(−1),while that derived from Phragmites australis(BPA)had a very high SSA,344.02 m^(2)g^(−1).All the biochars carried both positive and negative charges.Kalidium foliatum biochar(BKF)possessed more nega-tive charges,while Suaeda altissima biochar(BSA)contained more positive charges.In general,the halophyte biochars had a higher ash content and lower point of zero net charge(PZNC)value,compared with the biochars derived from glycophytes,which would imply their higher potential value as an acidic soil conditioner.