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991.
DBA/2J mice were exposed to a distinctive floor stimulus (CS+) and ethanol (2 g/kg) in a place conditioning paradigm. A different floor stimulus (CS?) was presented with saline. Mice injected just before or 30 min before CS exposure (Groups 0, ?30) showed conditioned place preference, whereas mice injected right after exposure to the CS (Group 5) displayed place aversion (Experiment 1). None of the other groups (?120, ?60, 15, 60) showed place conditioning. Handling and saline injection given just before or after CS exposure were unable to produce place conditioning (Experiment 2). However, there was a positive relationship between ethanol concentration (10% vs. 20%) and test performance, suggesting that peritoneal irritation influences place conditioning (Experiment 3). Overall, these findings support the suggestion that intraperitoneal injection of ethanol produces an initial short-duration aversive effect that is followed by a longer lasting positive motivational effect.  相似文献   
992.
The study measured the general attitudes towards disability of academics, administrative staff, and students in a small rural University. Respondents were also asked to comment on the nature of support that might be provided for a student with an emotional disability. There were some significant differences in level and nature of support for students with an emotional disability among academics, administrative staff, and students. These differences were related to the levels of comfort with, and sympathy felt towards, students with an emotional disability. However, overall the results suggest that university students with expressed emotional difficulties are liable to be relatively negatively regarded and are not liable to receive much concrete assistance for the difficulties they face. It is proposed that the data supports the notion that academics, of all the groups measured, are best placed to decide types of support for students with an emotional disability on a case by case basis.  相似文献   
993.
In this contribution, a theoretical and empirical framework based on work carried out at the Open universiteit (Ou) for a new approach towards the design, production and delivery of flexible, interactive learning materials for distance education is presented.

In the Research and Development centre of the Ou, a project has concentrated on the innovation of current approaches. This framework can also be considered as an advance organizer to reading the remaining articles from the Open universiteit in this issue of Distance Education.

A key feature of the innovation is that during the design phase, course developers have to define ‘models’ of the materials to be developed: a content model, a support model, a student model and the learning path. From a flexibility point of view especially, the ‘student model’ is of importance since it defines the student variables that will be taken into account when developing/ presenting alternative materials (basic content and/or embedded support). A computer‐based system, the ‘Interactive Learning and Course Development Environment (ILCE)’, was developed to support the work of course development teams and tutors on the one hand, and students on the other hand. The development system supports the work of the developers; the delivery system supports the study process of students. The delivery is realised as an on‐line course, on the World Wide Web.

Students start working with the ILCE‐system by following an intake procedure. They can make choices in relation to student variables that have been defined in the student model (profession, study intentions, context, etc.). Next, they can ‘on the fly’ generate a course. Rom the large repository of learning materials only those materials are selected and compiled that are in line with the student model of this specific student Furthermore, they can choose to study the materials on screen and/or make prints of the materials. Of course, in printing the materials they lose the interactive and dynamic possibilities of the computer learning environment  相似文献   

994.
A flash card computer program designed to increase decoding speed in reading was evaluated with a sample of 55 eight- to twelve-year-old Dutch poor readers by using a pretest-training-posttest control group design. The reading level of the poor readers was comparable to the reading level of normal readers in grade two. After 8 weeks of practicing (twice a week) for 30 minutes per session, children in the training group showed substantial improvements in decoding speed not only on pseudowords directly practiced during the training, but also in untrained pseudowords and in existing words. The no-training control group did not improve in decoding speed from pre- to posttest. The results, furthermore, indicate that syllable-bound processes play a role in phonological decoding in Dutch, and that the flash card method used in this study stimulates poor readers to decode letter strings into syllabic units, which leads to an increase in decoding speed. The role of the syllable in phonological decoding and the potential of a specific flash card technique as a means to improve decoding skills of poor readers are discussed.  相似文献   
995.
澳门特区自2007~2008学年开始实施15年免费教育,即9年义务教育、3年高中教育和3年学前教育免费.研究者运用网络调查及访谈法,对澳门特区免费幼儿教育政策进行研究,结果发现:(1)免费幼儿教育政策只适用于6家公办幼儿园和42家加入免费教育学校系统的私立幼儿园.(2)7家未加入免费教育学校系统的私立幼儿园需缴学费、补充服务费和选择性服务费,但可获政府发放的学费津贴和书簿费.家长很满意这一政策,并表示愿意继续送孩子上收费的私立幼儿园.(3)受访园(校)长、家长及教师对澳门的免费幼儿教育政策都很满意,教师特别满意政府推出的幼儿园教师津贴.(4)免费幼儿教育政策对私立园所的影响有所不同:有些私立园所为了生存而选择加入免费教育学校系统,有些私立园所则为了校政自主而选择不加入免费教育学校系统.客观上,高收费门槛令不同阶层家庭的幼儿自然分流.  相似文献   
996.
International Journal for Educational and Vocational Guidance - This study provides insights into how Chinese adolescents in Hong Kong interpret the concept of “meaning in life.” Data...  相似文献   
997.
998.
999.
A simple theory is presented for decoupling a pair of lossless coupled nonuniform transmission lines (CNUTL), with a common return and supporting TEM waves, into two lossless nonuniform transmission lines (NUTL). This theory is independent of the port terminations, symmetry conditions, etc. The method directly relates the line parameters of the lossless CNUTL's to those of the decoupled lines and vice versa; further, the matrix parameters of the CNUTL's as a four-port are explicitly expressed in terms of those of the decoupled lines as two-ports. This theory is then utilized to study the applications of CNUTL's as directional couplers.It is shown that for CNUTL's to behave as a codirectional coupler, each of the decoupled lines should be a proportional line, while for contradirectional coupler action, the two decoupled lines have to be duals of each other. The coupling response of the codirectional coupler is found to be periodic, while the phase shift between coupled and transmitted signals varies linearly with frequency. The coupling response of various contradirectional couplers with smooth transition at one of the ends, for which the decoupled lines are “basic NUTL's with hyperbolic solutions”, are studied in detail. It is shown that all these couplers have a high-pass response and that the CNUTL's with “hyperbolic cosine squared lines” as decoupled lines have the best response of all the CNUTL's considered.  相似文献   
1000.
Given the linear system x = Ax - bu, y = cTx, it is shown that, for a certain non-quadratic cost functional, the optimal control is given by uopt(x) = h(cTx), where the function h(y) must satisfy the conditions ky2?h(y)y>0 for y≠0, h(0) = 0 and existence of h-1 everywhere. The linear system considered must satisfy the Popov condition 1/k + (1 +?ωβ) G(?ω)>0 for all ω, G(s) being the y(s)/u(s) transfer function.  相似文献   
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