[Analysis on influences of guardians on behavior of left-behind children aged 3 to 7 years in countryside].

OBJECTIVE: To explore the influences of guardians on emotion and behavior of rural left-behind children aged 3 to 7 years. METHODS: A self-designed questionnaire of children's condition and Children Strengths and Difficulties Questionnaire (the edition for parents, SDQ) were used to investigate 805 left-behind children aged 3 to 7 years in countryside. RESULTS: The prevalence of difficulty among left-behind children was 3.5%, in male it was 4.1% and in female 2.7%, the difference was not significant (chi(2) = 1.154, P > 0.05) between male and female. The scores of peer communication problems among associate the left-behind children were (2.30 +/- 1.86), which was significantly higher than that (2.09 +/- 1.74) of not left-behind children (P < 0.05). The score of emotion symptom was (2.76 +/- 1.84) and the total score of difficulty was (11.41 +/- 4.77) among left-behind children was significantly higher than those of left-behind children with one parent stayed out (2.29 +/- 1.64) and (10.41 +/- 5.18), were significantly different (t = -2.489 - 2.006, P < 0.05), the score of social behavior (6.39 +/- 2.26) was significantly lower than that of left-behind children with father or mother stayed out (7.34 +/- 2.18, P < 0.001). The score of social behavior of children whose guardians had higher education level (7.02 +/- 2.21) was significantly higher than those with guardians who were illiterate or semiliterate (6.20 +/- 2.44, P < 0.01). CONCLUSIONS: There are evident problems in emotion and behavior among left-behind children with parents staying out. One of parents should stay home to care for children. To improve educational level of guardian will be beneficial to development of physical and mental health among left-behind children.

Comparison of chloroplast DNA between photoperiod-sensitive genic male sterile (PGMS) rice Nongken58S and its derivative sterile lines.

The ORF100, ORF29-TrnC(GCA) spacer, rps16 gene intron and TrnT(UGU)-TrnL(UAA) spacer of chloroplast DNA (cpDNA) of 6 photoperiod-sensitive genic male sterile (PGMS) rice, Nongken58S and its 5 derivatives, were amplified and sequenced. According to the result of ORF100 and ORF29-TrnC(GCA) spacer analysis, the cpDNA of japonica PGMS line Nongken58S was Japonica, and among those PGMS lines derived from Nongken58S, cpDNA of japonica 7001S and 3 indica lines 1103S, Peiai64S and Guangzhan63S were that of japonica, which was in accordance with the cytoplasm pedigree provided by their breeders. But the cpDNA of indica PGMS line W6154S was that of indica, which disaccorded with the cytoplasm pedigree, so we conjectured that the breeders had used the PGMS line as the male parent. Basing on the result of sequence analysis, we found single nucleotide polymorphism in rps16 gene intron and TrnT(UGU)-TrnL(UAA) spacer of these 5 japonica PGMS lines.