Children's understanding of representational change and its relation to the understanding of false belief and the appearance-reality distinction

This research concerns the development of children's understanding of representational change and its relation to other cognitive developments. Children were shown deceptive objects, and the true nature of the objects was then revealed. Children were then asked what they thought the object was when they first saw it, testing their understanding of representational change; what another child would think the object was, testing their understanding of false belief; and what the object looked like and really was, testing their understanding of the appearance-reality distinction. Most 3-year-olds answered the representational change question incorrectly. Most 5-year-olds did not make this error. Children's performance on the representational change question was poorer than their performance on the false-belief question. There were correlations between performance on all 3 tasks. Apparently children begin to be able to consider alternative representations of the same object at about age 4.     

Development of children's knowledge about unconsciousness

Children of ages 5, 6, 7, 8, and 10 years, and adults were asked whether people who are sound asleep and not dreaming could or would: (1) see, hear, listen, notice, think, wish, pretend, and feel things (primary-consciousness activities), (2), know that they are asleep, and know whether they are or are not engaged in primary-consciousness activities such as perceiving and thinking (reflective-consciousness activities), (3) deliberately decide to or try to perform mental or physical actions (control activities). Results indicated that the recognition that people do not engage in conscious mental activities when unconscious is still developing during the late middle-childhood years. We speculate that a developing understanding of consciousness may assist the development of an understanding of unconsciousness and vice versa, and that sensitivity to the phenomenology as contrasted with the content of mental states may be a late acquisition in the theory-of-mind area.     

Development of knowledge about the use of cues to aid prospective retrieval

Retrieval cues can be used to help one remember to perform tasks in the future and to relocate objects in the environment. However, in both tasks there are requirements for a retrieval cue to be effective as a mnemonic aid. For example, the cue must be associated with the target item, but it must not be ambiguous, and it must be appropriately placed. 2 studies assessed children's ability to evaluate the communicative quality of retrieval cues. In Study 1, 5-9-year-old children and adults evaluated the potential effectiveness of cues to remind themselves. In Study 2, 4-9-year-olds evaluated the potential effectiveness of cues for relocating hidden objects. Patterns of results were similar in both studies: young children first learned that the retrieval cue should be associated with the target and should be encountered for retrieval to occur. However, children often overlooked problems with the potential informativeness of the cues, such as ambiguity, and did not anticipate that such cues might be misinterpreted in the future. Children's difficulty in estimating their information needs may be related to their difficulty in monitoring their current comprehension state.     

Dewey and mathematical practice: revisiting the distinction between procedural and conceptual knowledge

We identify a recent trend in school mathematics as well as in some of the research literature in mathematics education: an emphasis on the practical uses of mathematics and an increased emphasis on verbalizations as opposed to numerical and computational skills. With tools provided by John Dewey, an early advocate of contextual and practical knowledge, we analyse the common research framework for discussing mathematical knowledge in terms of the procedural and the conceptual. We argue that procedural and conceptual knowledge should not be seen as opposites, and that the tendency to treat them as such might be avoided by emphasising the notion of operational skill. We argue that this is important in order for the students to gain both the contextual knowledge and the computational skill entailed in mathematical knowledge.     

由种子演绎出来的系列生物学问题

近几年，有关种子的考点在高考中频频出现，这说明种子是一个较好的知识载体，能够考察高中学生的生物学知识。现对种子的生物学问题作了整理、归纳和总结，列为以下四大类型。     

服装中的生物学

衣、食、住、行是人类最基本的生活需要。随着生活水平的不断提高,人们已不满足于吃饱穿暧,而追求更高层次的享受,表现在穿着上就是“穿得漂亮,穿出个性”。但人们在选择衣服时,很少会注意到它是否含有害物质。本文从生物学的角度介绍服装的原料及洗涤等方面的知识。     

论编辑的知识修养

提高编辑工作者的自身修养，是提高书刊质量的重要保证。编辑的修养是多方面的，本文只从编辑的知识修养这一主要方面阐述了提高其修养的主要内容及其重要性。     

港澳基本法差异研究

港澳基本法是"一国两制"理论在法律上的集中体现.它们的绝大部分内容是一致的.但由于港澳的地位、历史及法律传统的不同,两部基本法在篇章结构上、内容上有一些不同.     

有关蜜蜂的问题

初中生物学教材在“蜜蜂”一节中，简要介绍了三种类型蜂的形态结构、功能及其发育；在高中生物学教材生殖和发育中涉及到蜜蜂的特殊生殖方式和发育特点，在遗传和变异涉及到单倍体雄峰。现将学生对蜜蜂感兴趣的问题总结如下：     

人类对物理微观世界的认识

从对粒子物理学发展概况的简要叙述,回顾了从元素、原子、原子核和基本粒子的发展过程,特别是最近六十年以来基本粒子的发现和人类对物质结构的探索,揭示出物质物理微观结构的奥秘.     

Subject-matter knowledge and knowledge about students as sources of teacher presentations of the subject-matter

Pedagogical content knowledge is made up of several components. In this paper we concentrate on one of these: teachers' planned presentations of the subject-matter. We deal with two main sources of this component of pedagogical content knowledge: knowledge about the subject-matter and knowledge about students. Illustrations are given in two mathematical domains: functions and undefined mathematical operations. The paper concludes with a discussion of the nature of teachers' knowledge and the interconnections between the three constructs: subject-matter knowledge, knowledge about students, and knowledge about ways of presenting the subject-matter.     

雪灾涉及的物理问题

今年一月我国南方出现了五十年不遇的冰雪灾害天气,给国家造成了巨大的损失,引起了社会各界的广泛关注.关于南方雪灾中涉及的物理问题很多,本文拟从雪的形成、雪灾的形成,高压输电铁塔的倒塌等热点问题从物理学角度加以分析,并对日常生活中的雪灾防护作一些简单的介绍.     

Two-year-olds use the generic/nongeneric distinction to guide their inferences about novel kinds

These studies investigated two hundred and forty-four 24- and 30-month-olds' sensitivity to generic versus nongeneric language when acquiring knowledge about novel kinds. Toddlers were administered an inductive inference task, during which they heard a generic noun phrase (e.g., "Blicks drink milk") or a nongeneric noun phrase (e.g., "This blick drinks milk") paired with an action (e.g., drinking) modeled on an object. They were then provided with the model and a nonmodel exemplar and asked to imitate the action. After hearing nongeneric phrases, 30-month-olds, but not 24-month-olds, imitated more often with the model than with the nonmodel exemplar. In contrast, after hearing generic phrases, 30-month-olds imitated equally often with both exemplars. These results suggest that 30-month-olds use the generic/nongeneric distinction to guide their inferences about novel kinds.     

进口仪器设备采购过程中的一些商务常识

结合采购进口仪器设备过程中的合同内容及合同执行过程中的问题,介绍进口设备采购过程中涉及的商务常识。降低进口设备采购过程中的风险,进而保障采购人利益。     

Young children's ability to differentiate appearance-reality and level 2 perspectives in the tactile modality

A key acquisition in the child's developing knowledge of the mind is the subjective-objective distinction, which includes a clear understanding that things may appear to be other than the way they really are (appearance-reality distinction) and may present different appearances to self and others (Level 2 perspective-taking). Previous studies using tasks involving visual appearances have found that most children do not show such understanding until 4 or 5 years of age. However, a conceptual analysis of tactile as compared to visual and other perceptual experiences suggested the hypothesis that this understanding might appear earlier if the appearances the child must identify are tactile rather than visual. This hypothesis was supported by the results of 3 studies. In Studies 1 and 2, 3-year-old subjects could correctly indicate, for example, that an ice cube they were feeling with a heavily gloved finger did not feel cold to that finger (tactile appearance for the self), did feel cold to the experimenter's ungloved or thinly gloved finger (tactile appearance for another person), and was a cold ice cube, really and truly (reality). In contrast, and consistent with previous research findings, they were much poorer at distinguishing between real and visually apparent object identity, number, and color. Similarly, in Study 3 they tended to perform better on tactile appearance-reality tasks involving the properties of number, wetness, and intactness than on visual appearance-reality tasks that involved these same properties.     

Young children's knowledge about printed names

Four experiments examined young children's knowledge about the visual characteristics of writing, specifically personal names. Children younger than 4 years of age, even those who could read no simple words, showed some knowledge about the horizontal orientation of English names, the Latin letters that make them up, and their left-to-right directionality. Preschoolers also had some familiarity with the shapes of the letters in their own first name, especially the leftmost letter. Knowledge of the conventional capitalization pattern for English names emerged later, after a period during which children preferred names in all uppercase letters. When tested with personal names, the kind of word they know best, young children are surprisingly knowledgeable about the visual characteristics of writing.     

关于噬菌体的几个问题

1噬菌体的遗传物质是否只有DNA 高中阶段学习了噬菌体（bacteriophage,phage）及烟草花叶病毒等知识,往往可能产生这样的印象,认为噬菌体的遗传物质就是DNA。事实上噬菌体只是一类病毒的统称。噬菌体是感染细菌、真菌、放线菌或螺旋体等微生物的病毒,噬菌体具有病毒的一些特性：个体微小,可以通过滤菌器;没有完整的细胞结构,主要由蛋白质构成的衣壳和包含于其中的核酸组成;     

浅谈知识经济与高校改革

本文从知识形态出发 ,提出历史赋予高校培养创新型人才的使命 ,唯有改革才是必由出路。