太阳能捕集器

太阳每天向地球倾泻成万倍于人类活动所需的能量,人们需要解决如何廉价地开发太阳能的问题.而自然界则不存在这个问题."太阳能电池"就长在树上,绿叶的光合作用把太阳光转化为化学能,几乎为一切自然生态系统提供着能源.的确,人们可以从植物得到启迪:如何充分利用太阳光.     

Levels of phonological awareness and learning to read

The paper reports studies of segmentation performance by a Nursery group of children, who had not yet started to learn to read, and by Primary 1 and 2 groups, who were in the early stages of learning by a standard method of whole word acquisition combined with letter-sound learning. Rhyme and alliteration production tasks were applied, together with segmentation tasks requiring division of monosyllabic words or non-words of simple or complex structure into two parts, three parts, or as many parts as possible. Performance was related to the hierarchical model of the syllable which distinguishes a two-dimensional (2D) level (onset/rime), a three-dimensional (3D) level (initial consonants, vowel, terminal consonants) and many-dimensional (nD) level (phonemes). The hypothesis that phonological awareness (PA) normally develops down the hierarchy, from larger to smaller units, predicts that segmentation ability should emerge in the sequence 2D 3D nD. In practice, the reverse of this order was found. The results are discussed in relation to theories of the relationship between literacy development and the different levels of PA.     

Child abuse and neglect—rare, but perhaps increasing, phenomena among the samia of Kenya

This study shows that child abuse and neglect as understood in the West are comparatively rare phenomena among the Samia of western Kenya. The existence of an extended family situation and a strong clan structure are importantly related to positive care accorded to children. However, due to increased migration to towns, socioeconomic change, and interethnic marriages, the clan unit has been eroded thus resulting in cases of child abuse and neglect. Several such cases are reported in this study. The Samia traditionally practice the “evil eye” which is here considered to be a form of child abuse. Our findings, therefore, also have implications for previous efforts to define child abuse cross-culturally.     

An investigation of the situated learnability effects of single- and dual-modal systems in education: a report of music-oriented learning environment and science computer-assisted teaching studies

The evolution of the World Wide Web has encouraged a huge surfacing of e‐learning technologies over recent years. Often, such technology is rolled out devoid of consideration towards the way in which students process and assimilate information. To date, there exists inconclusive and contradictory evidence concerning learnability effects of single‐ and dual‐model systems in education. To overcome this, we advocate that the design of e‐learning systems requires a managed mix of elements grounded in cognitive psychology. In this paper, we report the results of a study concerned with determining an effective mix of multimedia elements. This is with regard to the situated learnability effects of single‐ and dual‐modal systems tested via ‘text only’ and ‘text and auditory–verbal’ conditions. We report on these experiments using science computer‐assisted teaching and music‐oriented learning environment, e‐learning environments developed to act as test platforms for this research. The results indicated that simultaneous presentation of identical information via text and narration was associated with enhanced learnability.     

大学排行榜之困

大学排行榜在全球各地风靡一时,在21世纪充满竞争、面向市场的学术界,大学排名势所难免,但因评选方法存在诸多缺陷以及排行榜自身的原因,大学排名活动已招致多方批评。排行榜存在的问题跟实践有关,而与原则无关,要解决这些问题,首先应确立公众普遍认可的排名原则,而为这些原则提供合适的衡量办法也必不可少。     

The genetic and environmental origins of language disability and ability

This study investigated whether genes affect language impairment to the same extent as they affect differences in language ability following up an earlier study of 579 four-year-old twins with low language performance and their cotwins (Viding et al., in press). The present study selected low-language twins from 6,963 pairs of twins from the Twins Early Development Study assessed for vocabulary and grammar by their parents at 2, 3, and 4 years of age. For impaired groups corresponding to the lowest scoring 5% and 10% at each age, twin concordances and model-fitting analyses indicated substantial genetic influence on the mean difference between affected children and the population (h2g), generally higher than for individual differences for the entire sample (h2).     

Environmental Education in Guangzhou in the People's Republic of China: Global theme,politically determined

This article is concerned with environmental education in southern China and with factors that have determined the nature of environmental curricula in secondary schools. Data are based on interviews with key players within the field of environmental education in the city of Guangzhou. Six interdependent themes became apparent in the primarily utilitarian conception of environmental education, namely, environmental education as (1) a response to environmental degradation and practical needs of society; (2) a knowledge-focused area of scientific learning in the national interest; (3) a field of study with Chinese characteristics; (4) a political tool and an element in national propaganda; (5) an administratively led and centrally controlled innovation; and (6) a field of study in conflict with mainstream education. These themes are conceptualised within a tripartite framework emphasising the political factor, the socio-economic factor and the environmental factor.