Associations between physical activity and health-related fitness – volume versus pattern

Approximately 3.2 million people die of non-communicable diseases (NCD) each year due to insufficient physical activity. Physical activity guidelines are possibly perceived as too demanding and might thus pose a barrier. We addressed the question if a more stable physical activity pattern is associated with higher levels of health-related fitness than one with high and low intensities, regardless of the physical activity level (PAL). Physical activity was objectively measured in 296 men and women (53.7 ± 8.94 years) with the SenseWear Pro Armband^®. Using this data, the PAL and a Gini index were calculated to report the physical activity pattern. Health-related fitness was expressed as a fitness index. PAL was weakly correlated to health-related fitness (r = 0.38, P < .0001). The Gini index was also weakly correlated to the fitness index (r = 0.23, P < .0001). Results of the ANCOVA showed that participants in the first quartile of PAL always scored significantly lower for health-related fitness than participants in quartile four, after adjustment for the Gini index. These results suggest that as long as the volume of physical activity is high, health-related fitness will be high as well, independent of the physical activity pattern or variability in intensities throughout the day.     

Identification of red colorants in van Gogh paintings and ancient Andean textiles by microspectrofluorimetry

Red lake pigments and dyes used in works of art were characterized by microspectrofluorimetry, a new tool in the field of cultural heritage. Emission and excitation spectra were obtained with high spatial resolution (8–30 μm) in cross-sections from paintings by Vincent van Gogh and Lucien Pissarro and from millenary Andean textiles. The fluorophores were identified by comparing their spectra with those from historic reconstructions assembled in a database. In the paints, purpurin and eosin lakes were detected. In the Paracas and Nasca textiles, dated from 200 B.C. to A.D.1476, purpurin and pseudopurpurin were the red dyes used. Carminic acid was detected in textiles dated close to the Inca Empire, A.D. 1000–1476. The results obtained with this new technique were confirmed and are in agreement with those obtained with conventional methods, requiring microsampling, such as HPLC-DAD-MS and SEM-EDX.     

A social network perspective on the management of product development programs

Creativity is essential to the performance of product development programs (PDPs). Most PDPs are designed around teams that jointly work together according to the product decomposition into components, the design and development procedure, and the methods of the final integration. Since the creative product development task requires the teams to combine and integrate input from multiple other teams, the team's structure of interaction is an important determinant of their creativity. In research and practice, however, little is known about the social networks of the teams and their creativity within PDPs. In this study we investigate different structural aspects of social networks of such teams and their creativity within two multinational PDPs. The main results of our investigation imply that many direct network contacts around a weekly intensity stimulate the creativity of teams of PDPs, whereas very open networks with a high information variety minimizes the team's creativity.     

Innovation studies—The emerging structure of a new scientific field

The scholarly literature on innovation was for a long time not very voluminous. But as shown in the paper, this is now rapidly changing. New journals, professional associations and organizational units within universities focusing on innovation have also been formed. This paper explores the cognitive and organizational characteristics of this emerging field of social science and considers its prospects and challenges. The research reported in this paper is based on a web-survey in which more than one thousand scholars worldwide took part.     

Changes in the relation between cognitive and metacognitive skills during the acquisition of expertise

This paper focuses on the transformation of general metacognitive skills of novices into domain-specific regulatory procedures of experts, and the relation of those skills to intelligence. Research has shown that the general metacognitive skills of novices, although partly correlated to intelligence, additionally contribute to learning outcome on top of intelligence. The metacognitive skills of experts appear to be domainspecific and unrelated to intelligence. Two experiments were conducted. The objective of the first experiment was to confirm and generalize these earlier results concerning the relation of intellectual ability, metacognitive skillfulness and learning of novices vs. advanced subjects. The objective of the second experiment was to investigate this relation under different conditions of task complexity. It was hypothesized that advanced subjects would regress to more novice-like behavior under very complex learning conditions (i.e., general metacognitive skills and intelligence would re-appear as combined predictors of learning outcome). On the other hand, low intelligent novices, irrespective of their metacognitive skillfulnes, were expected to fail on very complex problems. Results partly confirmed these hypotheses. Implications for the conditions under which metacognitive experiences should be implemented, are being discussed.     

Problem‐based distance learning of energy issues via computer network

Problem‐based learning (PBL) modified for distance education (PBDiL = Problem‐Based Distance Learning) has been used for teaching energy issues at Uppsala University, Sweden. Collaborative learning in groups of seven to eight students was enabled by computer communication and enhanced the use of Internet. Two different teaching methods have been tried and are compared, both being influenced by methods used in conventional face‐to‐face PBL. The problem presentation was entirely built on pictures, and examination through student reports was successful. A student remark, ‘I study on my own but yet not alone’ shows the importance of social contact.     

Developing science teachers' pedagogical content knowledge

This article discusses the concept of pedagogical content knowledge (PCK) within the context of science teaching. First, an attempt is made to define this concept within the tradition of research on teachers' craft knowledge and to identify possible purposes of research on PCK. From this point of view, recent research on science teaching is investigated. This investigation identifies teaching experience as the major source of PCK, whereas adequate subject-matter knowledge appears to be a prerequisite. Finally, an empirical study is presented which focuses on PCK with respect to a specific topic—that is, chemical equilibrium. The effects on teachers' PCK of participation in an in-service workshop and conducting an experimental course in classroom practice are reported. This leads to the identification of elements of PCK teachers can use to promote student understanding. It is concluded that research on topic-related PCK may complement research on student learning of specific topics. © 1998 John Wiley & Sons, Inc. J Res Sci Teach 35: 673–695, 1998.     

Professional knowledge affects action-related skills: The development of preservice physics teachers' explaining skills during a field experience

Professional knowledge is an important source of science teachers' actions in the classroom (e.g., personal professional content knowledge [pedagogical content knowledge, PCK] is the source of enacted PCK in the refined consensus model [RCM] for PCK). However, the evidence for this claim is ambiguous at best. This study applied a cross-lagged panel design to examine the relationship between professional knowledge and actions in one particular instructional situation: explaining physics. Pre- and post a field experience (one semester), 47 preservice physics teachers from four different universities were tested for their content knowledge (CK), PCK, pedagogical knowledge (PK), and action-related skills in explaining physics. The study showed that joint professional knowledge (the weighted sum of CK, PCK, and PK scores) at the beginning of the field experience impacted the development of explaining skills during the field experience (β = .38**). We interpret this as a particular relationship between professional knowledge and science teachers' action-related skills (enacted PCK): professional knowledge is necessary for the development of explaining skills. That is evidence that personal PCK affects enacted PCK. In addition, field experiences are often supposed to bridge the theory-practice gap by transforming professional knowledge into instructional practice. Our results suggest that for field experiences to be effective, preservice teachers should start with profound professional knowledge.     

Embedding inquiry-based practices in schools: The strategic role of school leaders

The context of this study were research and development projects in Dutch secondary education, particularly funded by government to combine practice-based research with school development goals for inquiry-based culture. Aiming at better understanding of the strategic role that school leaders play in embedding inquiry-based practices in schools, the research question of this study was to explore to what extent and how do school leaders use the opportunity of participating in funded research and development projects for encouraging and integrating inquiry-based practices in their schools? Differences concerning the integration of inquiry-based working in the school as professional learning community were examined, distinguishing between school leaders’ strategies of capacity building. Twenty-eight school leaders of Dutch secondary schools, involved in nineteen projects, were interviewed retrospectively. Analyses showed the majority of the school leaders to be convinced that inquiry-based working is important for their schools’ development as a professional community. Their strategies for achieving school level project significance differed in school leaders’ successive attention on personal or interpersonal capacity building with regard to inquiry-based practices. Moreover, while some school leaders were actively involved with capacity building right from the start of the research and development projects projects, almost two-third of the school leaders developed interest in inquiry-based practices during the projects and started to enact in the final year of the project. In discussing the results, it is proposed that the interaction of strategy and context needs further study, for instance to inform peer learning among school leaders that are novice and experienced in inquiry-based practices as a means to develop the school as a professional learning community.