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1.
Does achievement independent of ability or previous attainment provide a purer measure of the added value of school? In a study of 4000 pairs of 12-year-old twins in the UK, we measured achievement with year-long teacher assessments as well as tests. Raw achievement shows moderate heritability (about 50%) and modest shared environmental influences (25%). Unexpectedly, we show that for indices of the added value of school, genetic influences remain moderate (around 50%), and the shared (school) environment is less important (about 12%). The pervasiveness of genetic influence in how and how much children learn is compatible with an active view of learning in which children create their own educational experiences in part on the basis of their genetic propensities.  相似文献   

2.
Effects of high-rise living on infants' development were investigated in 1987-1988 in a high-rise residential area in Tokyo, using questionnaires on the daily behaviors of a total of 1,045 infants, completed by mothers and kindergarten teachers. Infants of high-rise living showed a delayed independence in fundamental daily customs compared with those of low-rise living. This could be ascribed to an over-attachment of mothers of high-rise living with their infants resulting from a reduced number of outings.  相似文献   

3.
Previous studies have indicated that the acculturation process may contribute to psychosocial and health problems among immigrants through the mediation of acculturation stress. This study focuses on adolescents with immigrant background permanently settled in the Croatian region of Dalmatia and the influences of the acculturation process on their dietary habits, nutritional behavior and perceived body-image. The survey was conducted on the total sample of 510 adolescents (aged 14-19) including 52 first generation and 248 second generation immigrants. The analysis included dietary habits and questions of restrictive diet as indicators of unhealthy influence on physical health. Psychological factors (stress and self-esteem) have been found to be associated with dietary habits, diet behavior and dissatisfaction with body-image among adolescents with significant differences by immigrant status. Immigrant status is viewed as a risk factor for psychological distress and unhealthy dieting behavior. Research stresses the need to study the interaction between acculturation and health not only from an individual perspective, but also from the broader socio-ecological context of population subgroups.  相似文献   

4.
We studied parental behaviour of two populations of Eurasian kestrels (Falco tinnunculus) living in environments with different reproductive constraints: a northern Italy population, resident, with relatively long reproductive season and almost stable prey availability, and a western Finland population, long-distance migrant, with short reproductive season and fluctuating availability of main prey (voles). The Finnish population was studied during a low vole availability year. We aimed to test the supposition that in variable environments the few pairs capable of breeding during low prey availability years show high-quality parental care. To estimate the quality of parental care in both Finnish and Italian pairs we measured the difference in the number of prey delivered by the male and by the female within each pair. The parental care, measured by that parameter, was greater among Italian pairs during both the incubation and early nestling periods. However, this was not the case in the late nestling period, when food requirements of offspring are greater. Moreover, the Finnish and Italian pairs produced about the same number of fledglings. Therefore, our data supported the initial supposition and we conclude that the few Finnish pairs capable of breeding in a low vole availability year show parental care similar to Italian pairs.  相似文献   

5.
A total of 257 healthy children (140 boys, 117 girls) varying in age from 5.7 to 18.5 years underwent graded exercise tests on a treadmill. Cardiorespiratory endurance capacity was assessed by determination of the ventilatory threshold, which was defined as the highest exercise intensity before a disproportionate increase occurred in pulmonary ventilation (VE) relative to oxygen uptake (VO2). The purpose of the present study was to investigate the relationship between the habitual level of physical activity (HLPA) and the cardiorespiratory endurance capacity in children. The HLPA was assessed by a standardized questionnaire. In boys and girls HLPA increased gradually with advancing age. For the group as a whole, the boys reached the highest values for HLPA. The most active boys reached the highest value for ventilatory threshold and the lowest value was found in the less active ones, except for the age span of 12-16 years. It is concluded that more active boys showed a higher cardiorespiratory endurance capacity, as assessed by the ventilatory threshold, compared to less active ones, except during puberty. It can be postulated that during puberty this effect may be overruled by the influence of other more dominant growth-related factors. In girls, because HLPA was rather low, there was no discriminative effect of HLPA on exercise performance, as would be expected.  相似文献   

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BACKGROUND/AIM: To determine the association of physical activity and the metabolic syndrome in a large national-representative sample of children. METHODS: This study was performed in 2003-2004 on 4,811 school students aged 6-18 years, selected by multi-stage random cluster sampling from six provinces in Iran. We assessed the level of physical activity using a standardized questionnaire, and categorized it to the tertiles. The metabolic syndrome was defined based on criteria analogous to those of the Adult Treatment Panel III. RESULTS: The participants comprised 2,248 boys and 2,563 girls with a mean age of 12.07 +/- 3.2 years. In all age groups, boys were more physically active than girls. The metabolic syndrome was detected in 14.1% of participants, and its prevalence was higher in those subjects in the 1st, 2nd and 3rd tertiles of physical activity, respectively (15.1 vs.14.2 and 13.1%, respectively, p <0.05). This difference was seen in boys, while no difference was found between girls in the 2nd and 3rd tertiles of physical activity. Physical activity was linked to a cluster of factors consisting of high-density lipoprotein-cholesterol and waist circumference, followed by triglycerides in boys, and of triglycerides, waist circumference and blood pressure in girls. In both genders, before and after adjustment for age and body mass index, low levels of physical activity significantly increased the risk of having the metabolic syndrome [in boys: OR: 1.8, 95% CI: 1.1, 2.1; and in girls, OR: 1.6 (1.1, 1.9)]. CONCLUSION: We found an association between physical activity and the metabolic syndrome, which was independent of body mass index and age. Children should be encouraged to have greater physical activity.  相似文献   

8.
This paper presents the socio-economic conditioning of somatic features in children and adolescents, as well as in adults, both men and women. The material used in the analysis was collected in 1990 in the Konin voivodeship (Poland). It comprises 1587-1608 boys and 2191-2213 girls at the age of 7-18 years. The adults consist of two groups: 1. aged 25-39 (3096 men and 4628 women), 2. aged 40-59 (4210 men and 3061 women). The metrical data comprise body height, body mass and BMI. Environmental (size of the district of residence) and social data (level of education and professional data of the parents) were taken into account. Multidimensional statistical analysis (step-wise) was applied to explain the variability of the somatic features under study in relation to the socio-environmental factors. It could be shown that the socio-environmental differentiation of the somatic features manifests itself in a different manner depending on the kind of feature, on the gender and on the age. In comparison with the girls the boys show a greater ecosensitivity of body height and mass and a lesser ecosensitivity concerning the BMI. Among all the factors describing "the quality of living conditions" the classically used indirect factors have a fundamental influence on the development of body height, body mass and BMI of boys, as well as on the body height of girls (e.g. parents' addiction to nicotine, physical effort). The social differentiation manifests itself most clearly in adult women's body mass and BMI and in men's body height. The level of education is a factor of relatively highest importance. It differentiates somatic features of men and women independently of their age (exceptions: body mass of younger women, BMI of older men). The occupational stratification differentiates women's somatic features (with the exception of the BMI of the older women) and body height of the younger men. The size of the district differentiates somatic features in younger women and men, apart from body height in men, and conditionally (Ha: one-sided) BMI in older women.  相似文献   

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10.
The aim of the study was to compare bone properties of two groups of students which strongly differ in the level of their everyday physical activity; the School of Medicine (SM) students and the Faculty of Physical Education (FPE) students, University of Zagreb. Quantitative ultrasound parameters--broadband ultrasound attenuation (BUA) and speed of sound (SOS) were measured. Quantitative ultrasound index (QUI) and estimated bone mineral density (BMD) were calculated by the device software. The final study sample consisted of 165 students from SM (94 males and 71 females) and 215 students from the FPE (164 males, 51 females). Sixty eight percent of FPE students and 21% of SM students reported a high level of everyday physical activity (P < 0.001). All ultrasound parameters were significantly higher in FPE students than in SM students (at the P < 0.001 level). The multiple regression model of the QUI confirmed that the school students attended was the single significant predictor variable for both genders. Our data indirectly showed the beneficial role of physical activity on bone properties.  相似文献   

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The aim of the present study is to evaluate blood levels (PbB) in a group of 500 (245 M, 255 F) children and adolescents of Campania (Italy) aged from 0.197 to 16.915 years, 269 (136 M, 133 F) of whom lived in urban zones and 231 (109 M, 122 F) in rural zones. PbB was assayed by electrothermal atomic absorption spectroscopy. The parents of the examined subjects children were interviewed about common risk factors for lead exposure using a standardized questionnaire. The PbB of children living in urban zones were significantly higher than the PbB of those living in rural zones (60.0 +/- 3.0 mg/L vs. 40.0 +/- 2.0 mg/L, p < 0.001). A PbB higher than 100 mg/L was found in 27 children (5.4%). We observed a significant correlation between age and PbB (p < 0.001, r = 0.529). Our data regarding children and adolescents demonstrate that the prevalence of PbB higher than 100 mg/L is greater in children living in urban areas (6.89%) than in subjects living in rural areas (3.89%). The findings can be explained by the higher presence of risk factors of Pb exposure in urban areas. Our data, if compared with those of previous studies concerning children of Campania, show a clear decrease of PbB. The correlation that we found between age and PbB indicates that long-term exposure at low doses more than a more intensive but short-term exposure seems to be important for the increase of blood lead levels.  相似文献   

14.
The purpose of the study was to find out differences in moderate to vigorous physical activity among non-overweight, overweight and obese children, and between boys and girls. The sample included 364 children (179 boys and 185 girls), aged 6.4 years (+/- 0.3 SD). Physical activity was assessed by 7-day questionnaire. Age adapted BMI was used as overweight and obesity indicator. The children were divided into non-overweight, overweight and obese groups. It was found out, that there are significant differences in non-overweight, overweight and obese children (p < 0.05). Boys were significantly (p < 0.05) less moderate to vigorous physical active than girls, especially in indoor activities. There were also significant differences (p < 0.05) in moderate to vigorous physical activity among non-overweight and obese boys and among overweight and obese boys in weekends and total weekly activity. In girls there are significant differences (p < 0.05) in non-overweight, overweight and groups in weekends and total weekly activity. It is possible to conclude, that obese boys and overweight and obese girls, are prone to less physical activity.  相似文献   

15.
The relationship between nutritional status, measured by height for age, and cognition, measured by WISC full-scale IQ, was studied in a longitudinal sample of 459 urban Guatemalan children, aged 4-9 years, from a disadvantage community of the fringe of Guatemala City, examined annually over a 3 year period. Socioeconomic status (SES) was controlled by developing a composite index for each home. The mean IQ differed significantly from the lowest to the highest quartiles of stature, the difference between the two extreme quartiles being approximately 0.3 SD of IQ. There was a significant interaction between SES and stature in their effects on IQ. Whereas nutritional status and SES affected IQ in an additive fashion in the upper three SES quartiles, there was no difference in IQ attributible to stature among children from the most disadvantaged homes. This analysis indicates that the mild-to-moderate protein-energy malnutrition (defined by height for age) that is prevalent among children from disadvantaged environments in developing countries is significantly related to cognitive development. However, in the poorest homes, SES is seen as a more important determinant of cognitive development than stature.  相似文献   

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环境因子对硬骨鱼类性腺发育成熟及其排卵和产卵的调控   总被引:21,自引:2,他引:21  
对影响硬骨鱼类性腺发育成熟及其排卵和产卵的诸多环境因子进行了综述(如水温、光照、降雨和水流、水体化学因子、水体生物因子以及环境污染(环境胁迫)等),并对其调控机制进行了阐述,侧重强调了环境胁迫对硬骨鱼类生殖的影响,旨在从生态学角度为保护鱼类种质资源提供对策。  相似文献   

18.
The current study aimed to determine the prevalence of obesity and overweight among Indian women living in Punjab, India and in Vienna, Austria. A series of 115 women ageing between 17 and 80 years (x = 38.7 yrs; +/- 14.5) was enrolled in the present study. 65 women lived in the district of Jalandhar in Punjab, 50 Punjabi women lived in as migrants in Vienna Austria. Data collection comprised an anthropometric analysis including stature height, body weight and the body mass index (BMI). For classification of the weight status the Indian BMI cutoffs defined by the WHO for Asian Indians were used. Data concerning dietary patterns and lifestyle parameters were collected by structured interviews using a standardized questionnaire. Among both subgroups overweight and obesity were highly prevalent. Underweight (18.5%) was significantly more prevalent in Punjab than in Vienna (6.0 %), while overweight and obesity were more frequently found among Punjabi women in Vienna (26.0%; 54.0%) than among Punjabi women in India (9.2%; 24.6 %). Analysing lifestyle and dietary patterns it turned out that energy dense meals were preferred and fat and sugar were used frequently among both subsamples. A statistically significant relationship between dietary habits and weight status could not be proved.  相似文献   

19.
The effects of environmental temperature and photoperiod on wheelrunning activity were studied in the diurnal red squirrel,Tamiasciurus hudsonicus. From 1 July to 22 November 1973 eight squirrels were maintained in separate cages in an outdoor shelter. Activity usually began before sunrise in the summer an early fall and after sunrise in the late fall. Wheel-running usually persisted throughout the day and ceased about the time of sunset in the summer and early fall. In late fall cessation frequently occurred after sunset. Neither changes in temperature nor photoperiod were found to separately account for the seasonal changes. Multiparameter analysis of variance was found to be a powerful statistical tool for analyzing the data. Six models for predicting the onset of activity were constructed and tested.This publication is based on a Master's thesis by B. R. Bahnak.  相似文献   

20.
B N Il'in 《Genetika》1983,19(6):1024-1032
The significance of physical development parameters of children and teen-agers in assessment of the state of health in this population group is emphasized. A brief analysis of some investigators' viewpoints relative to the ratio of biological and social factors in the physical development of children is given. Novel methodical approaches to more exact tabulation of the data concerning the physical development of children and teen-agers are suggested, instead of regional scales of regression generally used in this country. Statistical parameters of height-subgroup and not those of the whole age-sex group are assumed as a basis for such tables. These tables applicable for a long-term use all over the country will enhance reliability and the value of work within the programme of genetic monitoring of the population physical development. Attention is drawn to the significance of size variations in weight-, height- and other subgroups (except for the traditional parameters) in the whole age-sex group. Quite as important is determination and control of values of weight/height and other ratios in each height-subgroup.  相似文献   

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