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161.
Effects of social and visual contact on the oxygen consumption of juvenile sea bass measured by computerized intermittent respirometry 总被引:1,自引:0,他引:1
J. Herskin 《Journal of fish biology》1999,55(5):1075-1085
The resting metabolic rate (RMR) of juvenile European sea bass Dicentrarchus labrax L. (47·5±1·5 g, 15–18 cm) was 126·2±2·5 mgO2 kg−1 h−1 , and temporal patterns of oxygen consumption were not affcted by visual contact or social interaction with conspecifics. The results suggest that a group effect is not present in juvenile D. labrax , thus no selective advantage of shoaling is gained through lowered metabolism in this facultative schooling species. 相似文献
162.
云南巧家金沙江干热河谷的植被分类 总被引:12,自引:3,他引:9
采用法瑞植物社会学学派的排表法对巧家干热河谷的植被进行系统分类,并以数量分类方法(组平均法)进行验证,结果将当地植被划分为一个群目(order)、两个群属(alliance)、四个群丛(association)。本文还详细探讨了当地植被的生境及区系、生态学特征,同时对比了当地植被与元谋干热河谷植被的异同。 相似文献
163.
Priti Chandrakar 《Biological Rhythm Research》2017,48(1):99-112
The present study investigated social jetlag in school students of the Raipur district of Chhattisgarh. The sample consisted of 919 school students from six different schools, age range 12–19 year, comprising of both males (n = 513) and females (n = 406). Two inventories, the 19-item MEQ and MCTQ (Munich Chronotype Questionnaire) were employed. Data analysis (SPSS) used t-test, Chi-square test, ANOVA, and correlation. The results revealed that 73.9% of the sample had social jetlag. There were significant effects upon social jetlag of chronotype, gender, and the use of an alarm clock. Owls were at a higher risk of having social jetlag. There was a significant positive correlation between the amount of social jetlag and the time spent watching television. From these results, it is concluded that there is prevalence of social jetlag, particularly among boys and those who use an alarm clock. The results also lead to the prediction that those school students with social jetlag will be predisposed to health hazards associated with it in the future. Thus it is recommended that school students must be provided with sleep education so that they understand the role of sleep on health and do not become sleep deprived. 相似文献
164.
Kim BJ Lee BY Chung HK Lee YS Lee KH Chung HJ Ock MS 《The Korean journal of parasitology》2003,41(1):75-77
The status of pinworm (Enterobius vermicularis) egg positive rate of primary school children in Geoje island was investigated by using adhesive cellotape anal swap method, in September, 2002. Total egg positive rates of E. vermicularis were 9.8% (74/754) and those of male and female were 10.8% and 8.7%, respectively. Among three schools examined, Myeongsa primary school showed the highest egg positive rate (12.6%) followed by Yeoncho [9.8% (26/266)] and Geoje [9.1% (35/385)]. As for the age groups, the 2nd grade had the highest egg positive rate (15.3%), whereas the 5th grade showed the lowest egg positive rate (2.6%). The above result led us to confirm that the egg positive rates of E. vermicularis in primary school children in Geoje island were not significantly different from the those in the whole country including urban and rural areas, showing more than 10%. 相似文献
165.
Since 1979, fishery-independent data and fishery-dependent data have been used to estimate trends in the abundance of the northeastern stock of spotted dolphins in the eastern tropical Pacific. Data collected aboard tuna vessels have been used to estimate trends in relative abundance, while data collected from fishery-independent research vessels have been used to estimate trends in actual abundance. One of the largest discrepancies between the two data sources is that tuna vessels tend to report dolphin schools that are 400%—500% larger than schools observed by research vessels. After comparing research vessel and tuna vessel observations overlapping in space and time, it appears that either measurement error or selective reporting of large schools is the most likely explanation for the disparity. Comparing single-species schools against portions of mixed- species schools introduced bias. Revised fishery-dependent abundance estimates were generated using only single-species dolphin schools, resulting in estimates that appear more similar to recent fishery-independent abundance estimates.
correctable in fishery-dependent data, suggesting that data on mixed-species schools should not be considered if fishery-dependent data are to be combined with fishery-independent data for stock assessment purposes. 相似文献
correctable in fishery-dependent data, suggesting that data on mixed-species schools should not be considered if fishery-dependent data are to be combined with fishery-independent data for stock assessment purposes. 相似文献
166.
Alexander Hew Dale Crooke 《Arts Education Policy Review》2019,120(1):19-32
This article explores the extent to which recent policy-based advocacy for music in Australian schools has been guided by economic arguments. This exploration was driven by emerging commentary on the rise of neo-social education policy, which is said to have reframed equality and social justice in education as tools for economic agendas. To explore the presence of this neo-social ideology in school music advocacy, key Australian policy documents have been analyzed using Critical Discourse Analysis. Results show that while current advocacy does champion social and subjective benefits, these benefits are ultimately justified in economistic terms. While caveats to these findings are discussed, the argument is made for new education policies that adequately value subjective wellbeing and social justice as goals in their own right. 相似文献
167.
A total of 4,287 primary school children, comprising 1,740 males and 2,547 females in Arochukwu local government area of Abia
state Nigeria were examined for clinical signs of dermatophytoses. About 873 (20.4%), consisting of 505 males and 368 females
had lesions consistent with dermatophytoses. The disease was more prevalent in males (29%) than females (14.4%) in a ratio
of approximately 2:1 (P < 0.05). The infection rate increased from 16.8% in the 4–6 year age group to a peak of 28.1% in the 10–12 year age bracket
and dropped sharply to 5.6% in the 16–18 year group. The highest prevalence (39%) was observed among males aged 10–12 years
while females 16–18 years had the lowest prevalence (2.5%). Tinea capitis was the predominant clinical type of dermatophytoses,
and occurred in 13.7% of the total population studied and 67% of lesion positive cases. Trichophyton soudanense and Trichophyton tonsurans the predominant aetiological agents of dermatophytoses with a prevalence of 26.2% and 21.6%, respectively. Others include
Trichophyton mentagrophytes (18.8%), Epidermophyton floccosum (8.3%), Microsporum audouinii (6.4%), Microsporum gypseum (6.0%), Trichophyton rubrum (5.5%) and Microsporum ferrugineum (7.3%), which was isolated for the first time in Nigeria. 相似文献
168.
成聪聪 《现代生物医学进展》2006,6(7):81-83
为了了解在学校体育改革大潮中,高校体育教育专业大学生对学校体育改革的认知情况,运用文献资料法、问卷调查法、数理统计法,对体育教育专业学生对学校体育改革状况的认知情况进行研究。研究结果显示:高校体育教育专业学生对学校体育改革状况的认知情况不太乐观,制约因素主要有学校信息不畅、个人学习习惯问题及经济因素。 相似文献
169.
Background: The relationship between H. pylori infection and anemia in childhood is still unclear. The aim of the study was to examine the association between H. pylori infection and anemia or iron deficiency in school‐age children and in infants. Materials and Methods: Six‐ to 9‐ year‐old Israeli Arab children (N = 202) and infants (N = 197) were examined for hemoglobin and ferritin levels. ELISA was used to detect H. pylori antigens in stool specimens collected from the participants. Household characteristics were obtained through personal interviews with the mothers. Results: The prevalence of anemia was 15.5 versus 5.5% in H. pylori‐positive and ‐negative school‐age children, respectively and 34.5 versus 29.8% in H. pylori‐positive and ‐negative infants, respectively. The Mantel–Haenszel age‐adjusted prevalence ratio (PR) and 95% confidence intervals (CIs) were 1.6 (95%CI 1.0, 2.6). In multivariate analysis controlling for socioeconomic variables, H. pylori infection was associated with 2.8 higher prevalence of anemia only in school‐age children: adjusted PR 2.8 (95% CI 0.9, 9.3). The adjusted mean difference in hemoglobin levels between H. pylori infected school‐age children and uninfected ones was ?0.372 gr/dL (95% CI ?0.704, ?0.039) (p = .04). The respective mean ferritin difference was ?6.74 μg/L (95% CI ?13.38, ?.011) (p = .04). Such differences were not found in infants. Conclusions: H. pylori infection is associated with higher prevalence of anemia in school‐age children independently of socioeconomic variables. Such association was not observed in infants. These findings are of clinical and public health importance. 相似文献
170.
中国产业生态学发展的回顾与展望 总被引:2,自引:0,他引:2
作为一门探讨产业发展与生态环境之间相互关系的学科,产业生态学需要对我国生态化转型重大战略选择做出贡献。本文回顾与评述了产业生态学在我国的发展,指出产业生态学在我国的起源具有多源性,既有着中国传统哲学的传承,也有着多种工程学科的经验升华,还有着前苏联经验的烙印。在进入新世纪后,我国产业生态学的发展开始深受西方学术的影响,逐渐建立起较为系统的教育、研究和组织体系。这些成果体现在课程开设、学科建设、机构成立和研究发表等方面。本专栏评述了其中的代表性领域并收录了相关成果,例如生命周期评价和产业共生等。在探讨产业生态学学科发展的现实性、理论性及政治性基础上,提出了需要进一步观察、总结和提炼过去的发展实践,需要关注中国根本性和战略性的核心问题,需要建构产业生态学的中国学派,需要加速建设产业生态学的教育和学科发展体系,并接受生态文明转型这一历史使命的挑战,为中国乃至世界产业生态学发展以及产业生态化做出贡献。 相似文献