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141.
ABSTRACT:  The purpose of this study was to use a validated instrument to determine the attitudes and knowledge of high school teachers regarding food irradiation, and to determine the correlations among their knowledge and attitudes and certain demographic variables. Knowledge and attitudes about food irradiation were measured in selected high school family and consumer sciences teachers ( n = 121) who taught Food and Nutrition, Food Science and Technology, and/or Food Production Management and Services, via a 24-item instrument with 6 factors. Results revealed these teachers held neutral to positive attitudes about the safety of irradiated foods, their perception of the risk of foodborne illness, and learning about food irradiation, and neutral to negative perceptions of their understanding of food irradiation and their competence to teach about it. These teachers had a moderate knowledge base regarding food irradiation. Teachers' attitudes regarding the safety of food irradiation were positively correlated with their perceived understanding of food irradiation, actual knowledge of it, and competence to teach about it. Their perceived understanding of food irradiation was positively correlated with competence to teach about it, knowledge, and attitudes toward the safety of food irradiation. The only demographic variable correlated with knowledge or attitudes was teachers' previous food irradiation educational experiences. These data suggest the importance of education for family and consumer sciences teachers concerning food irradiation.  相似文献   
142.
For many years now, most countries of the world have increasingly valued the headteacher as a powerful force in facilitating school and staff development. Such recognition has resulted in widespread training programmeseven in the poorest countries. In Spain, however, there has been, until very recently, considerable ambiguity over the role of the headteacher. This uncertainty is manifested in the appointment system of headteachers and the lack of commitment to training. This paper seeks to show the reasons for this situation, through an evaluation of recent legislation, the impact of Franco's legacy on education and the current preoccupation with democratic government at all levels. The paper highlights important changes of attitude towards the role of the head now taking place, mainly at local levels, and encourages the government to ensure that examples of effective training, emanating from these ideological shifts, are recognised and contained within national programmes.  相似文献   
143.
Echolocation     
G. Marimuthu 《Resonance》1996,1(5):40-48
Bats are capable of avoiding obstacles that they encounter, even in complete darkness. This is because they emit ultrasound (high frequency sound) and analyse the echo produced when the sound hits objects on their path. This article describes the hunting flight of bats and how echolocation is useful in prey capture. Prey capture without the aid of echolocation by some bats is also described.  相似文献   
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INTRODUCTION The world population of buffaloes(Bubalus bubalis)has been estimated at over172million head,more than97%(167.6million)of which are in Asia and the Pacific region,mainly in India(97.7million)and Pakistan(25.5million)(FAO,2004).About98%of buffaloes in the region are raised by small farmers owning less than two hectares of land and less than five buffaloes(Mudgal,1992).In general,the water buffalo is regarded as more productive,healthier and more useful than the cow,especiall…  相似文献   
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Education is intimately associated with communication, and so may utilize any technology that is able to support a process that enables information to be transferred from one location to another. This paper describes the meaning of the term multi-media data base and presents a model of its potential role in aiding message creation for the purposes of communicating educational material using many parallel channels. Some of the problems associated with the implementation of such systems are outlined.  相似文献   
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Musso  Sandrine  Fanget  Delphine  Cherabi  Kémal 《Prospects》2002,32(2):207-213
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