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961.
Sasaki and Biro (2017, Nature Communications, 8, 15049) show that pairs of pigeons can increase the efficiency of their homing routes over several ‘generations’ in which pair members are gradually replaced by naïve birds. Their findings show that socially transmitted cumulative alterations of behavior are not unique to humans and suggest a way to examine potential mechanisms of cultural evolution.  相似文献   
962.
This article investigates how culture shapes instruction in three early care and education programs on the Flathead Indian Reservation. Interviews with eight early childhood teachers as well as classroom observations were conducted. The investigation is framed by the following research question: How does the culture of the family and community shape curriculum? Data analysis suggested that ongoing communication with parents and community about teaching within a culturally relevant context, building a sense of belongingness and community through ritual, and respecting children, families, and community were essential to defining the Native American Indian culture within these early learning programs.  相似文献   
963.
In this paper, two theoretical positionsregarding the developmental origins of thephoneme as a unit for lexical representationand processing are outlined – theaccessibility and emergent positions. OurLexical Restructuring Model (Metsala & Walley1998), which is consistent with the secondposition, focuses on the role of vocabularygrowth in prompting the implementation of morefine-grained, segmental representations forlexical items in childhood; this restructuringis viewed as an important precursor to theexplicit segmentation or phoneme awarenessskills implicated in early reading success.Empirical evidence that supports this model issummarized, including preliminary results fromone of our most recent studies. Severalsuggestions are made for future research thatwill lead to a better understanding of thedevelopment of spoken word recognition and thelinks between speech- and reading-relatedabilities.  相似文献   
964.
Differential weighting of response alternatives and confidence testing have been proposed as ways to assess partial knowledge on multiple-choice tests. 211 students in an educational measurement course took their midterm examination under one of three procedures. Results from those students administered the test under conventional directions provided a baseline for comparing, in terms of reliability and validity, the results from students who took the test under the differential weighting of response alternatives or the confidence testing instructions. Reliability was estimated by the split-half technique. Validity was estimated by correlating midterm test scores with scores on a final examination. This investigation provides some support for the contention that validity can be improved using more sophisticated testing techniques. Suggestions for the conduct of more definitive studies were offered.  相似文献   
965.
Current printed courses of the Open universiteit (Ou) have been designed according to a variety of course models; for example the ‘learning unit model’ or the ‘textbook‐workbook model’ (van den Boom & Schlusmans 1991). Considering the potential of the ILCE approach (Valcke & Martens, this issue), one can imagine new and innovative course models that build on the interactivity and flexibility possibilities of such an environment An essential feature of the ILCE approach is that developers can consider student differences when designing and producing learning materials.

In this article we will explore the problem of adapting the delivery of learning materials to student characteristics in relation to a course based on ‘cases’ in the law domain. Two different study modes are researched: a study mode that starts with the theory and next moves to practical work with the cases versus a study mode that starts with the practical work and next moves to the theoretical base.

Two studies are presented. Within the exploratory study, the research questions focus on the potential interrelations between student characteristics and the preference/choice for one of the two study modes. From the results can be concluded that almost all students from the Open universiteit prefer a theory‐based study mode, because they have a relatively large amount of experience with this study mode and because they find it a successful study mode.

In the second study, an experimental design is adopted with students studying in one of four different conditions: two study modes of printed learning materials and two study modes of interactive learning materials. In contrast with the exploratory study students clearly indicate a more diverse preference for certain study modes. Students also differ in their preference for the delivery mode. However the more traditional study and delivery mode (theory‐based and printed learning material) remains more popular. Again this might again be due to the greater experience students have with this approach. Only two student characteristics are significantly related to opting for the practice‐based study mode: the experience level with a study mode and one's prior knowledge with the subject matter. Comparable results were detected regarding the preferred delivery mode: students with little prior knowledge more readily prefer a printed book, probably because they have a better overview.  相似文献   

966.
967.
968.
The transition to adult roles usually occurs within a normative age span. By focusing on preadolescence to late adolescence using 2-wave panel data, this research seeks to develop a more informed picture of how "early" exit from the student role and "early" entry into the adult role of parent or spouse reflect factors operating prior to adolescence. The short term consequences of adult role transition on teenage status aspirations, life plans, other psychological orientations, and parental influence are also examined. Even though multiple role transition is frequently observed, only leaving school early appears to be related to preadolescent career decisions and academic performance in high school. The determinants of early transition to the role of parent or spouse do not appear to be socioeconomic origins, parental child rearing techniques or other specific influences, academic ability or performance, or preadolescent aspirations, as has generally been hypothesized in the literature. Research dilemmas and policy implications are discussed.  相似文献   
969.
Social workers in the schools can take positive and immediate action to address teenage pregnancy through the use of interventive models that help teenagers avoid the risk of unwanted pregnancy. The present article describes and empirically supports 1 such school-based model. The author 1st delineates the major problems associated with teenage pregnancy and then relates the preventive model to prior research and details its implementation in school settings. A discussion of reslults from the model's field evaluation is followed with implications for school social workers. The model reported here is directed to all adolescents rather than focusing on a "high-risk" population. The risk of pregnancy is assumed to be a normal part of adolescent development. Grounded in an intterpersonal conceptualization of teenage pregnancy and in related empirical research, the school-based model helps young men and women acquire the requisite skills for preventing unwanted pregnancy. The program requires school social workers to meet with 12-18 teenage students of both sexes and to provide them with basic information on human sexuality, reproduction and contraception. These topics are covered by lectures, demostrations, discussion and audiovisual presentations. Through instruction, feedback and reinforcement, student learn how to talk about sensitive topics, stand up for their rights and be convincing and effective when carrying out decisions. Homework assignments are designed to develop the students'skills in interactions with dating partners, parents and friends. The clinical applicability and effectiveness of this prevention training model is documented through a study conducted in an urban high school. 36 informed and consenting sophomores of both sexes were randomly assigned either to an interventive group or to a non-treatment control group. Compared to the latter, the former had more accurate knowledge of human reproduction and contraception after the intervention. Buttressing these and other positive results, the students' enthusiastic feedback left little doubt that they enjoyed the group process and were interested in the training. Moreover, analyses of follow-up data on coital activity, the use of contraceptives, and family planning decisions revealed that the training had produced striking effects. Decision making tests, behavioral performance tests, follow-up questionnaires and videotaping of behavior during stressful interpersonal situations were among the evaluation techniques used.  相似文献   
970.

Objective

To evaluate the effect of anti-vascular endothelial growth factor (VEGF) on juxtafoveal choroidal neovascularization (CNV) secondary to multifocal choroiditis (MFC) and wet age-related macular degeneration (AMD). Methods: In this retrospective, comparative study, 20 unique eyes with CNV were divided into two groups: 10 patients affected by MFC and 10 patients diagnosed with wet AMD. They all received local intravitreal (IVT) injections of ranibizumab, with 6 months of follow-up. Retreatment injections were performed based on findings suggestive of active neovascularization.

Results

Significant improvements were observed in the juxtafoveal CNV lesions, and average central macular thickness decreased in both groups following the anti-VEGF therapy (P<0.05). The average number of injections used in MFC patients was 1.6, while three injections on average were used in wet AMD patients (Z=?2.844, P=0.009). Best-corrected visual acuity was significantly improved in MFC patients after anti-VEGF therapy (P<0.05), and there was no significant difference in wet AMD patients between before anti-VEGF therapy and 6 months later (P>0.05).

Conclusions

IVT ranibizumab resulted in good clinical outcomes for juxtafoveal CNV secondary to MFC and wet AMD, but the average number of injections used in MFC was fewer than that used in wet AMD over a 6-month observation period. Compared with the wet AMD group, visual acuity was obviously improved in the MFC group at 6 months.
  相似文献   
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