[Association between speed and endurance performance with sleep duration in children and adolescents].

OBJECTIVE: To analyze the association between sleep duration and athletic performance, and provide scientific basis to improve the 50 m and endurance performance in children and adolescents. METHODS: All the 119 462 subjects aged 9-15 years in both genders were sampled from 2014 National Physical Fitness and Health Surveillance by using stratified random cluster sampling method, to measure the height, weight, 50 meters and endurance performance and investigate sleep duration with questionnaire. Their body mass indexes (BMI) were calculated and the students' 50 m, endurance run scores and sleep durations were assessed. Binary Logistic regression was used to analyze the difference between the different sleep groups, and multifactor Logistic regression was used to analyze the relationship between the sleep condition and athletic performance. RESULTS: The prevalence of insufficient sleep was 94.67% in the total subjects, the prevalence was higher among the girls (95.26%)than the boys (94.09%, χ2=80.99, P<0.001), and higher among the urban (95.41%) than the rural students(93.93%, χ2=128.48, P<0.001).The children with sufficient sleep had better performance in 50 m and endurance run scores( χ250 m=10.10, P50 m＜0.01; χ2endurance run=21.76, P<0.001). Logistic regression analysis after controlling the gender, area, grade and BMI showed that children with adequate sleep showed better results(OR50 m=1.14, 95%CI50 m=1.05-1.23, P50 m<0.01; ORendurance run=1.21, 95%CIendurance run=1.11-1.31, Pendurance run<0.001). As for gender, the excellent rates of 50 m and endurance run scores in the boys with adequate sleep were higher (P<0.001), but there were no significant difference in 50 m and endurance run excellent rates in the girls of different sleep conditions. The excellent rates of 50 m and endurance run in the urban children and the endurance rate in the rural children and adolescents with adequate sleep were higher than those with insufficient sleep (P<0.01) while there were no significant difference in the 50 m excellent rates between the different sleep groups in rural areas. The 50 m and endurance run excellent rates of the children and adolescents with adequate sleep in each grade were higher than those of the children in the same grade with insufficient sleep (Pprimary students' endurance performance<0.001, and the rest P<0.05). Children and adolescents with normal BMI and overweight who slept well had better performance in 50 m (P<0.05). The endurance run excellent rate of children and adolescents with adequate sleep in each BMI group was higher than that in children and adolescents with insufficient sleep in the same BMI group (Pmalnutrition<0.01, Pnormal<0.01, Poverweight<0.05, Pobesity<0.05). The children and adolescents were divided into different groups according to the sleep duration,the one who slept less than 7 hours had lower 50 m excellent rate than the other groups with longer sleeping duration (P<0.01) and the rate in the ones who slept more than 9 hours was the highest (P<0.001).The endurance excellent rate in the children and adolescents who slept more than 9 hours was significantly higher than that in the other groups (P<0.001).There was no significant dose-response relationship in excellent rates and sleep durations. CONCLUSION: The prevalence of insufficient sleep has increased, and the sleep condition in children and adolescents is severe. Children and adolescents with sufficient sleep have better athletic performance, so we should strengthen the prevention and control of the lack of sleep in children and adolescents.

In vitro antioxidant activities of endophytic fungi isolated from the liverwort Scapania verrucosa.

We investigated in vitro antioxidant activities of 49 endophytic fungi isolated from the liverwort Scapania verrucosa. Based on morphological and molecular identification, the endophytic fungi isolated were classified into seven genera (Hypocrea, Penicillium, Tolypocladium, Chaetomium, Xylaria, Nemania, and Creosphaeria), all belonging to one family (Xylariaceae). By screening with the 2,2'-azino-di(3-ethylbenzthiazoline-6-sulfonic acid) (ABTS) decolorization assay, the ethyl acetate extracts of five endophytic fungi (T7, T21, T24, T32, and T38 strains), which exhibited remarkable Trolox equivalent (TE) antioxidant capacity (ranging from 997.06 to 1248.10 µmol TE/g extract), were selected and their antioxidant capacity was further evaluated by assays for 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging, hydroxyl radical scavenging, reducing power, and ferrous ion chelating. The ethyl acetate extracts of two endophytic fungi (T24 and T38) were found to have comparable scavenging abilities on both DPPH-free radicals (93.9 and 88.7%, respectively, at 50 µg/mL) and hydroxyl radicals (97.1 and 89.4%, respectively, at 2 mg/mL) when compared with those of the positive controls (ascorbic acid and butylated hydroxytoluene, respectively). Although their reducing powers were similar to that of butylated hydroxytoluene, as indicated by absorbance (0.35 and 0.30 at 50 µg/mL, respectively), only the T38 strain's ethyl acetate extract showed ferrous ion chelating ability (92.9% at 1 mg/mL) comparable to that of the EDTA-2Na control. These endophytic fungi in S. verrucosa are a potential novel source of natural antioxidants.

Fourier-phase method for the location of moving objects.

A novel method is presented that permits one to locate a moving object. According to this method, the change in location of a moving object can be detected from its Fourier spectrum. This method has the advantages of a high-precision locating mechanism and the capacity to permit one to ignore the change in the orientation and the size of the moving object. The principles are introduced, a computer simulation and experimental demonstration are given, and the practicality of this method is discussed.

Immunization of neonates with trivalent oral poliomyelitis vaccine (Sabin).

A study was carried out between November 1981 and April 1982 on the immunological effect of administering trivalent live, oral polio vaccine to 200 mature healthy neonates from Henan Province, China. The initial dose of vaccine was given at 3 days of age, and 2 months thereafter antibodies to poliovirus types 1, 2, and 3, respectively, were detected in 46.7%, 60.7% and 48.6% of the neonates; after the second dose, the levels were 86.9%, 95.3%, and 97.2%, with geometric mean titres of 1:106.2, 1:349.8, and 1:232.5. Almost 100% of neonates exhibited antibodies after the fourth dose of vaccine. Eighty-two percent of the neonates excreted poliovirus for at least a week after the initial dose of vaccine, and this increased to 99% after the second dose. Seroconversion at 4 months of age was similar to that of a group of controls who received their initial dose of vaccine at 2 months of age; however, immunization of neonates induced immunity to poliovirus at the earliest possible age.