Quality incentive based congestion control for multimedia communication over IP networks

In this paper we introduce a framework for using quality as an incentive to promote proper application level congestion control. Through integrating a joint-source channel coder and feedback-based congestion control scheme, we are able to construct accurate and efficient quality incentives. The framework is applicable in all network architectures where end-to-end congestion control may be used, and is as such not specific to either best-effort or traffic class-based architectures. The concept is presented along with preliminary simulations that highlight the resulting rate control accuracy. We also discuss how to implement some well-known congestion control schemes within our framework.     

Attentional learning and flexible induction: how mundane mechanisms give rise to smart behaviors

Young children often exhibit flexible behaviors relying on different kinds of information in different situations. This flexibility has been traditionally attributed to conceptual knowledge. Reported research demonstrates that flexibility can be acquired implicitly and it does not require conceptual knowledge. In Experiment 1, 4- to 5-year-olds successfully learned different context-predictor contingencies and subsequently flexibly relied on different predictors in different contexts. Experiments 2A and 2B indicated that flexible generalization stems from implicit attentional learning rather than from rule discovery, and Experiment 3 pointed to very limited strategic control over generalization behaviors in 4- to 5-year-olds. These findings indicate that mundane mechanisms grounded in associative and attentional learning may give rise to smart flexible behaviors.     

Coaches' attitudes towards placebo interventions in sport

Placebo-induced performance enhancement is a new controversial issue in competitive sports. Coaches have control over the use of placebos, but their practices and attitudes were barely studied to date. In this survey 96 coaches from regional, national and international levels were asked about their practices and attitudes concerning placebo use in sports. Results revealed that 90% of the respondents were aware of placebo effects. Many (44%) coaches admitted to administering a placebo to their athletes. Those working at international level have administered placebos more often than the others (P = .02). Two thirds of the coaches agreed to the wider use of placebos in sport. Respondents who have used placebos in the past reported improved athletic performance. They also agreed more to the wider use of placebos than the coaches who previously did not use a placebo (P = .001). Team sport coaches use more often placebos than coaches working with individual athletes (P = .05). Only 10% of the sample thought that their athletes would refuse a hypothetical performance enhancer supplied by them. After a successful placebo intervention, only 15% of the coaches would administer it again without consulting the athlete. Overall, the coaches are optimistic about placebo use in sports. Close to half of them, especially those coaching at higher levels of competition, may use it regularly while achieving positive results.     

Teachers in retreat: The teacher as a dialogical self and the risks of an excessive formalization of its role

The aim of this paper is to explore the identity of the teacher as a dialectical being that is in permanent construction, to identify some obstacles teachers might find in this process while operating in an institutional framework, and the effects these could have upon the teacher and the goals she pursues with her students. By ruling out the idea of identity as an autonomous self that can be constructed with no ties with its context, we propose that identity is dialogical and is built through the relationships we establish with others. This fact situates the relationship between the student and the teacher at the center of pedagogical practices and allows us to establish the ideas of teacher presence and integrity as central elements for the moral development of students. In this context, we identify the excessive institutionalization of the role of the teacher as a cause for the reduction of identity and a defensive retreat to the possible outcomes of being judged by strictly formal criteria, which in turn can hinder the relation between student and teacher and risks possible negative consequences in the moral growth of both.     

What is Intended,What is Realized,and What is Learned? Teaching and Learning Biology in the Primary School Classroom

Within the framework of variation theory, 7- to 12-year-old students’ ways of understanding cellular respiration and photosynthesis were investigated against the background of their teachers’ teaching. Eighteen students were selected by the teachers and interviewed by the researcher. Lessons were observed and video recorded, and stimulated-recall interviews with the teachers were conducted. The students’ understanding of the function of oxygen and sugar in plants was described in four categories. The study concludes that young students can develop complex understanding if opportunities to learn are presented. The opportunities depended mainly on the language used by the teachers, such as metaphors, pointing out critical aspects of the object of learning. The study has implications for the relationship between teachers’ competence and students’ learning.     

Gender and Performance in Mathematical Tasks: Does the Context Make a Difference?

This study investigates how the context of mathematical tasks affects the performance of young children (ages 5–11). Subjects were 523 children from age 5 to 11. Three contexts of mathematical tasks (stereotypically boys’ contexts, stereotypically girls’ contexts and neutral contexts) are examined in three age groups (young, medium, and old). Boys’ and girls’ mean scores were compared for each age group in each of the three contexts. The data show that girls’ performance is affected by the context of the task while boys’ performance is not. The comparison between boys and girls in the three different contexts showed that in neutral contexts, the scores of boys and girls are similar. In (stereotypically) boys’ contexts, however, boys score significantly higher than girls. In (stereotypically) girls’ contexts, a significant interaction is found between age and gender, showing that the way girls are affected by such contexts depends on their age. The implications of these findings for gender-fair mathematics learning are discussed.     

Reference and Liaison Librarians: Endangered Species or “Vital Partners?” Views of Academic Library Administrators

Abstract

Reference, liaison, subject librarianship: all of these terms traditionally describe a combination of research assistance, instruction, and collection management. This study used structured interviews with 15 librarians at 14 geographically dispersed, medium to large academic institutions to investigate the current state of reference and liaison librarianship. Library administrators’ views are important to understanding the future of this work since they advocate for resources if they see the necessity. Findings included agreement on the goals of the work and the urgent need to communicate its value in the current higher education landscape; however, the specific means of communication and the types of work that being a partner could include varied.