Studying studies on teacher reflection and action: An appraisal of research contributions

For decades a substantial body of research on teacher reflection and action has been conducted. This research contains a wealth of information on teachers’ thinking about their daily work in classrooms. But what do these studies tell us about the linkage between thought and action in actual teaching? How do they contribute to our understanding, or do they, in the very selection of their methods, ‘tell only half the story’? To address these concerns, we have engaged in a critical appraisal to learn about the scope and limitations of research contributions and identify criteria that may shed light on exactly what aspects of teacher learning and development are being studied.This appraisal uses an analytic framework to position the various studies that have been conducted. From our analysis, which focuses on the validity criterion of closeness between type of research question and data collection methods, we conclude that the research would profit from a set of more detailed criteria to address some of the limitations inherent in approaches to studying teacher reflection and action.     

“What is a good digital library?” – A quality model for digital libraries

In this article, we elaborate on the meaning of quality in digital libraries (DLs) by proposing a model that is deeply grounded in a formal framework for digital libraries: 5S (Streams, Structures, Spaces, Scenarios, and Societies). For each major DL concept in the framework we formally define a number of dimensions of quality and propose a set of numerical indicators for those quality dimensions. In particular, we consider key concepts of a minimal DL: catalog, collection, digital object, metadata specification, repository, and services. Regarding quality dimensions, we consider: accessibility, accuracy, completeness, composability, conformance, consistency, effectiveness, efficiency, extensibility, pertinence, preservability, relevance, reliability, reusability, significance, similarity, and timeliness. Regarding measurement, we consider characteristics like: response time (with regard to efficiency), cost of migration (with respect to preservability), and number of service failures (to assess reliability). For some key DL concepts, the (quality dimension, numerical indicator) pairs are illustrated through their application to a number of “real-world” digital libraries. We also discuss connections between the proposed dimensions of DL quality and an expanded version of a workshop’s consensus view of the life cycle of information in digital libraries. Such connections can be used to determine when and where quality issues can be measured, assessed, and improved – as well as how possible quality problems can be prevented, detected, and eliminated.     

Evaluating a digital library self-archiving service: The BDBComp user case study

In this article, we present an overview of a self-archiving service for the Brazilian Digital Library of Computing (BDBComp) and describe a user experiment conducted to evaluate it. This experiment involved several potential real users, including computer science graduate students and professors, and archivists/librarians. The results of this study and their implications for similar services are described and analyzed, following sound statistical principles, which can serve as a basis for other similar studies. These results and their analysis indicate that we have successed in building a usable, efficient and learnable self-archiving service, properties which are essential to bring users to the system.     

Comparison of three-dimensional lower extremity running kinematics of young adult and elderly runners

The objective of this study was to compare the three-dimensional lower extremity running kinematics of young adult runners and elderly runners. Seventeen elderly adults (age 67-73 years) and 17 young adults (age 26-36 years) ran at 3.1 m x s(-1) on a treadmill while the movements of the lower extremity during the stance phase were recorded at 120 Hz using three-dimensional video. The three-dimensional kinematics of the lower limb segments and of the ankle and knee joints were determined, and selected variables were calculated to describe the movement. Our results suggest that elderly runners have a different movement pattern of the lower extremity from that of young adults during the stance phase of running. Compared with the young adults, the elderly runners had a substantial decrease in stride length (1.97 vs. 2.23 m; P = 0.01), an increase in stride frequency (1.58 vs. 1.37 Hz; P = 0.002), less knee flexion/extension range of motion (26 vs. 33 degrees ; P = 0.002), less tibial internal/external rotation range of motion (9 vs. 12 degrees ; P < 0.001), larger external rotation angle of the foot segment (toe-out angle) at the heel strike (-5.8 vs. -1.0 degrees ; P = 0.009), and greater asynchronies between the ankle and knee movements during running. These results may help to explain why elderly individuals could be more susceptible to running-related injuries.     

Anticipatory strategies of team-handball goalkeepers

Abstract

This study seeks to discover whether handball goalkeepers employ a general anticipatory strategy when facing long distance throws and the effect of uncertainty on these strategies. Seven goalkeepers and four throwers took part. We used a force platform to analyse the goalkeeper's movements on the basis of reaction forces and two video cameras synchronised at 500 Hz to film the throw using 3D video techniques. The goalkeepers initiated their movement towards the side of the throw 193 ± 67 ms before the release of the ball and when the uncertainty was reduced the time increased to 349 ± 71 ms. The kinematics analysis of their centre of mass indicated that there was an anticipatory strategy of movement with certain modifications when there was greater uncertainty. All the average scores referring to velocity and lateral movement of the goalkeeper's centre of mass are significantly greater than those recorded for the experimental situation with bigger uncertainty. The methodology used has enabled us to tackle the study of anticipation from an analysis of the movement used by goalkeepers to save the ball.     

A case analysis of semantic technologies for R&D intermediation information management

It is evident that companies and research centres can find a myriad of instruments to fund their R&D (Research & Development) activities. Due to the dynamics of the information management in these circumstances there is a need for intermediary businesses intervention. Consequently, intermediary companies are thus involved in a complex process that needs to be managed and controlled. Within this scenario an Information Technology (IT) platform, named RDi-Advise, was developed by EgeoIT using semantic technologies to support R&D process decisions. This case analysis describes the development and implementation of the platform including the lessons learned during the activity period.     

A polymeric micro-optical interface for flow monitoring in biomicrofluidics

We describe design and miniaturization of a polymeric optical interface for flow monitoring in biomicrofluidics applications based on polydimethylsiloxane technology, providing optical transparency and compatibility with biological tissues. Design and ray tracing simulation are presented as well as device realization and optical analysis of flow dynamics in microscopic blood vessels. Optics characterization of this polymeric microinterface in dynamic experimental conditions provides a proof of concept for the application of the device to two-phase flow monitoring in both in vitro experiments and in vivo microcirculation investigations. This technology supports the study of in vitro and in vivo microfluidic systems. It yields simultaneous optical measurements, allowing for continuous monitoring of flow. This development, integrating a well-known and widely used optical flow monitoring systems, provides a disposable interface between live mammalian tissues and microfluidic devices making them accessible to detection∕processing technology, in support or replacing standard intravital microscopy.     

Components of attack response inhibition in fencing: Components of attack response inhibition in fencing

Applying the Go/No-Go paradigm to fencing, we investigated the relationship between the moment at which the No-Go signal appeared after a movement had been initiated and the time required by fencers to suppress the motor execution of a step-lunge. Secondarily, we determined a time threshold from which movement inhibition results in an error. The No-Go stimulus was represented by a real attack movement. 18 elite fencers and a fencing master were included in the study. Four force plates measured the horizontal components of the fencer's and master's reaction forces, which were used to calculate the time components of the attack and the response inhibition process. Also, the velocity and displacement of the master's and fencer's respective centres of mass were estimated using inverse dynamics. In all cases, cognitive inhibition processes were completed after the onset of movement. Movement time was calculated using four time components (muscle activation, muscle deactivation, transition and braking time). The results obtained revealed that cognitive processes were not significantly affected by the timing of the appearance of the No-Go signal. In contrast, movement time and its time components tended to decrease when the time delay between the No-Go stimulus and the onset of the fencer's movement increased. In conclusion, any attempt to withhold an attack movement when it has already started leads to an error that increases the risk of being hit by the opponent, especially when attack is inhibited within 150?ms after the movement has started.