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61.
Learning Environments Research - We investigated teachers’ perceptions of an online inservice teacher course in China and its outcomes, as well as connections between these two types of...  相似文献   
62.

In two dimensions (2D), representations associated with slopes are seen in numerous forms before representations associated with derivatives are presented. These include the slope between two points and the constant slope of a linear function of a single variable. In almost all multivariable calculus textbooks, however, the first discussion of slopes in three dimensions (3D) is seen with the introduction of partial derivatives. The nature of the discussions indicates that authors seem to assume that students are able to naturally extend the concept of a 2D slope to 3D and correspondingly it is not necessary to explicitly present slopes in 3D. This article presents results comparing students that do not explicitly discuss slopes in 3D with students that explicitly discuss slopes in 3D as a precursor to discussing derivatives in 3D. The results indicate that students may, in fact, have significant difficulty extending the concept of a 2D slope to a 3D slope. And that the explicit presentation of slopes in 3D as a precursor to the presentation of derivatives in 3D may significantly improve student comprehension of topics of differentiation in multivariable calculus.

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63.
Since late 2020,China and the United States,the world's two largest economies,have embarked on regulatory reforms to boost the regulatory development of genetic...  相似文献   
64.
An etiological study was designed to investigate the onset and development of drinking and driving among adolescents who recently received their driver’s license. A theoretical framework, derived from Problem Behavior Theory, was applied in order to identify environmental, personality and behavioral factors associated with drinking and driving. Among students who reported that they had driven a motor vehicle in the past three months (N=1416), 33 percent of the males and 22 percent of the females (who averaged 16.7 years) reported “drinking at least two drinks on a single occasion prior to driving” at least once in the previous three months. Personality factors (including perceived ability to drive after drinking, tolerance of drinking and driving, and lack of self-confidence in avoiding drinking and driving situations), perceived environmental factors (perceived car availability and friends modelling of drinking and driving) and behavioral factors (riding with a drinking driver and marijuana use) accounted for a large proportion (49%) of the variance in reported drinking and driving. It is recommended that school-based, peer-led educational programs be designed which target young adolescents prior to the age at which legal driver license is obtained. The programs should be broad-based and consider drinking and driving within the larger context of drinking and driving related behaviors and traffic safety in general.  相似文献   
65.
Biodeterioration of Incralac used for the protection of bronze monuments   总被引:2,自引:0,他引:2  
Outdoor bronze sculptures are highly susceptible to corrosion in many environments and organic coatings are widely used for their protection. The purpose of this study was to determine the susceptibility of the commonly used coating Incralac to biodeterioration by microorganisms. A yeast was isolated from a bronze statue treated with Incralac and its ability to degrade Incralac was determined using growth curves, scanning electron microscopy (SEM), and electrochemical impedance spectroscopy (EIS). The organism grew slowly on Incralac in liquid culture, but SEM images demonstrated its ability to adhere to Incralac coated metal. Additionally, the yeast caused a rapid drop in the low frequency impedance of Incralac coated metal that was not observed under sterile conditions, indicating that the organism accelerated deterioration of the coating. The potential for microbial growth to accelerate deterioration of Incralac should be considered when developing a maintenance strategy for the protection of outdoor metal monuments.  相似文献   
66.
In this study 149 kindergarten children were assessed for knowledge of letter names and letter sounds, phonological awareness, and cognitive abilities. Through this it examined child and letter characteristics influencing the acquisition of alphabetic knowledge in a naturalistic context, the relationship between letter-sound knowledge and letter-name knowledge, and the prediction of Grade 1 phonological awareness and word identification from these variables. Knowledge of letter sounds was better for vowels and for letters with consonant–vowel names than for those with vowel–consonant names or names bearing little relationship to their sounds. However, there were anomalies within each category reflecting characteristics of the individual letters. Structural equation modelling showed that cognitive ability, comprising receptive vocabulary, non-verbal reasoning, rapid automatized naming of colours, and phonological memory significantly contributed to alphabetic knowledge and phonological awareness. In turn, letter-name knowledge but not phonological awareness predicted letter-sound knowledge and subsequent reading skill.This research was supported by a grant from the Social Sciences and Humanities Research Council of Canada to the first author. Thank you is extended to the participating schools and children and to Ian Newby-Clark for his orientation to AMOS. Michelle Bell, Shelly Moretti and Jodi Page have since graduated from the University of Guelph  相似文献   
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68.
Little is known about the relative effects of post‐secondary learning services for students with learning disabilities. We compared outcomes for students with learning disabilities who selected to: (1) take an academic learning success course (course‐intervention), (2) have regular individual interventions (high‐intervention) or (3) use services only as needed (low‐intervention). Pre‐ and post‐test comparisons revealed improvements in academic self‐efficacy and academic resourcefulness for students in the course‐ and high‐intervention groups. The course‐intervention group also showed decreases in their failure attributions to bad luck and increases in their general repertoire of learned resourcefulness skills in comparison to the high‐intervention group and had significantly higher year‐end GPAs in comparison to the low‐intervention group. Here we find positive outcomes for students with learning disabilities taking a course that teaches post‐secondary learning and academic skills.  相似文献   
69.
Efforts to represent knowledge effectively have been central to progress in various aspects of medical informatics. These efforts range from relatively simple "electronic textbooks" to fairly sophisticated knowledge-based systems, which function as well as, or even better than, human experts faced with similar problems. Knowledge bases have been developed in many fields, but the relatively limited domains and structured language of medicine, as well as the importance of information in the provision of good medical care, have made research in medical knowledge representation an area of intense activity. This paper reviews representative knowledge bases and knowledge-based systems in medicine: electronic textbooks such as PDQ and the Hepatitis Knowledge Base (HKB), rule-based systems such as MYCIN, causal models (e.g., CASNET), and hypothesis- or frame-based systems, exemplified by PIP and INTERNIST-1. The paper describes the relationships among divergent approaches and provides a sense of current and future trends. It examines problems in knowledge-based systems, particularly in knowledge representation and acquisition, and the responses to these challenges. The latter include the use of domain-independent software shells for constructing knowledge bases, the adaptation and use of previously existing knowledge bases, and multiple uses of the same knowledge base for different purposes.  相似文献   
70.
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