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971.
Math anxiety impedes performance in simple arithmetic tasks. Anxiety constrains working memory capacity and particularly the attentional functions of the central executive. The experiment reported here explored how interactivity mitigated the impact of math anxiety on the performance of elementary school students with simple additions. It manipulated two independent variables. The first was the length of the additions—involving either 7 or 11 number tokens (the value of the tokens ranged from 1 to 20). The other was the level of interactivity: in the low interactivity condition participants could not touch or point to the number tokens that configured the sums, and in a high interactivity condition participants could manipulate the tokens as they saw fit in deriving their answer. The length of the addition had an impact on accuracy, with longer sums leading to poorer performance. However, overall, performance in the high interactivity condition was superior, in terms of accuracy, absolute calculation error and efficiency, than performance in the low interactivity condition. Mathematics anxiety significantly predicted performance in the low interactivity condition, but not in the high interactivity condition. These results suggest that working memory resources are augmented through interactivity with the physical problem presentation, defusing the impact of anxiety on performance.  相似文献   
972.
Teachers are expected today to assess student understanding as an integral part of instruction, using a combination of various assessment methods and tools, among which are observing students solve problems in class and listening to their mathematical discussions. The aim of our study is to explore what it might mean for a teacher to hear students and to interpret their talk and actions. Analysis of an interview with Ruth – an experienced elementary school teacher – after she observed two of her students solve a mathematics problem, suggests four types of her interpretation: describing, explaining, assessing and justifying. This analysis illustrates the complexity of the way Ruth hears her students, as is indicated even in the relatively simple case of describing. Using various sources of data we also analyze different characteristics of Ruth’s hearing for the describing and explaining types of interpretation and examine possible resources for her over-hearing, compatible-hearing, under-hearing, non-hearing and biased-hearing.  相似文献   
973.
OBJECTIVE: The main objective was to know social representations about child maltreatment (severity, etiology, and intervention strategies) of the general population and the professionals working with children in the Caribbean area of Colombia. METHOD: Sample was composed for 402 participants. From this pool of participants, 111 of them were working in child protection, 95 worked with children but not in the child protection system and 196 pertained to the general population. All participants answered to a questionnaire composed by 86 items. The questionnaire was developed to assess (1) the perceived severity of different typologies of child abuse, (2) opinions about risk factors for child maltreatment and sexual abuse, and (3) opinions about the most adequate ways of intervention with perpetrator of child abuse. RESULTS: Sexual abuse is considered as the most severe typology of child maltreatment and emotional abuse is considered as more severe than physical abuse. No differences between groups were found in perceived severity of typologies of child maltreatment. Differences in the social representation about the etiology of child maltreatment were found. Professionals working in the child protection system give more value to characteristics of parents and to the socio-economic and familiar environment in the etiology of child maltreatment than participants from the general population. Prevention and treatment programs for abusers were considered as the more relevant strategies against child maltreatment. DISCUSSION: Findings of present study suggest that social representations about child maltreatment of general population and professionals from the Caribbean area of Colombia are similar than social representation observed in other regions and countries. It is important to take into account that child labor and child poverty were considered as non-severe typologies of child maltreatment. Moreover, findings suggest that people from general population in the Caribbean area of Colombia have a relevant knowledge about agencies working for child protection.  相似文献   
974.
The assessment system of a Canadian medical education program is described. The M.D. Program at McMaster University features the central use of clinical cases as the basis for learning, and the fostering of independence in learning by students. The assessment system, designed to match the objectives and methods of learning, is guided by several principles. These include a balanced emphasis on a range of objectives, the use of on‐going informal feedback, defined and shared responsibilities in assessment, and the design and use of measures which most appropriately match the objectives. More than ten years of experience has pointed out several lessons: if self‐directed learning is held as important, there is a trade‐off between excessively specific objectives, on the one hand, and too little guidance on the other. This attempt to create a balance between these extremes produces a degree of unevenness in the assessment system. External influences such as the national licensing examinations have some effect on the learning climate. It is predicted that the basic elements of the assessment system will remain in place, but some specific changes will occur. These include a clearer statement of objectives on which assessment can be based, the improvement of measurement tools, and an increased emphasis on the training of those who participate in the assessment system.  相似文献   
975.
Science & Education - In order to increase scientific competence within the general population, it is important that teachers and educators have a realistic image of science and scientists,...  相似文献   
976.
977.
Thirteen Ph.D. students took part in interviews focussed on the nature of their own learning of mathematics. In analysing these interviews an unexpected category emerged concerning the students awareness of others as having particular types of learning goal. In this paper we explore the three levels which we discerned within this category and link them to the notion of cognitive empathy. We suggest that differences in ones own cognitive style are linked to differences in the ability to empathise with those who have alternative learning goals. We also consider how these two features – cognitive style and cognitive empathy – may come to be linked.  相似文献   
978.
For a surface mounting machine(SMM)in printed circuit board(PCB)assembly line,there are four problems,e.g. CAD data conversion,nozzle selection,feeder assignment and placement sequence determination. A hierarchical planning for them to maximize the throughput rate of an SMM is presented here. To minimize set-up time,a CAD data conversion system was first applied that could automatically generate the data for machine placement from CAD design data files. Then an effective nozzle selection approach was implemented to minimize the time of nozzle changing. And then,to minimize picking time,an algorithm for feeder assignment was used to make picking multiple components simultaneously as much as possible. Finally,in order to shorten pick-and-place time,a heuristic algorithm was used to determine optimal component placement sequence according to the decided feeder positions. Experiments were conducted on a four head SMM.The experimental results were used to analyse the assembly line performance.  相似文献   
979.
The purpose of this article is to describe findings from a study of teachers’ social interaction during discussions about students’ thinking. The goal of the discussions was for the teachers to interpret their students’ thinking as revealed from work on non-routine, thought-revealing mathematical tasks, known as model-eliciting activities. The research reported in this article focuses on instances during the discussions when the teachers engaged in what the researcher termed ‘mini-inquiries’, occasions during which the teachers inquired into why their students thought about the associated model-eliciting activities as they did or when the teachers inquired into the underlying mathematical complexities associated with the model-eliciting activities. During these mini-inquiries, the teachers typically engaged in one of four types of interaction patterns that enabled them to meet some of the challenges of attending to students’ thinking that are described in United States reform documents.  相似文献   
980.
Objective: The aims of this research were to purify and identify the 130 kDa (CagA) protein ofH. pylori clinical isolate HP97002 and evaluate the relationships between the purified 130 kDa (CagA) protein and gastric diseases. Methods: The procedure for isolating the protein included 6 mol/L guanidine extract, size exclusion chromatography and elusion from gel. Sera of 68 patients with gastric diseases (44 with chronic gastritis, 15 with atrophic gastritis, 7 with peptic ulcer disease, 2 with gastric cancer) were obtained, and the serological response to CagA was studied by Western-blot using the purified protein. Results: The purified protein was 130 kDa and preserved good antigenicity and revealed basic isoelectric point about of 8.1. Among 68 sera, 43 sera could recognize the purified protein associated with chronic gastritis 47.7% (21/44), atrophic gastritis 86.7% (13/15), peptic ulcer disease 100% (7/7), gastric cancer 100% (2/2). Compared with each other, the difference was significant (χ2=13.327,P=0.004), and 130 kDa (CagA) protein was associated with severe gastric diseases (r s=0.442,P=0.001). Conclusion: The 130 kDa (CagA) protein was associated with severe gastric diseases. Project supported by the China Medical Board (96-628) and Zhejiang Province Hygiene Bureau (2000 A055)  相似文献   
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