Teaching Science Through Pictorial Models During Read-Alouds

This study examines how three elementary teachers refer to pictorial models (photographs, drawings, and cartoons) during science read-alouds. While one teacher used realistic photographs for the purpose of visually verifying facts about crystals, another employed analytical diagrams as heuristic tools to help students visualize complex target systems (rainbow formation and human eye functioning). Another teacher used fictional cartoons to engage students in analogical storytelling, communicating animal camouflage as analogous to human “blending in.” However, teachers did not always explicitly convey the representational nature of pictorial models (analog and target as separate entities). It is argued that teachers need to become more aware of how they refer to pictorial models in children’s science books and how to promote student visual literacy.     

Best Practice in Middle-School Science

Using socio-ecological theory, this study explores best practice (educational practices correlated with higher student performance) in middle-school science. Seven schools with consistently higher student performance were compared with three demographically similar, average-performing schools. Best practice included instructional approaches (relevance and engagement, inquiry, differentiated instruction, collaborative work, moderate amounts of homework, and integration of language literacy and science) and administrative practices (nurturing a climate of opportunity to succeed in science, offering professional development based on data and dialogue, engaging teachers in standards-based curriculum revision and alignment, and recruiting the right fit of teacher). It is argued that best practice entails multiple levels of teaching and administrative praxis that together form a school-wide socio-ecological system conducive to higher performance.     

Development and evaluation of an interactive electronic laboratory manual for cooperative learning of medical histology

This article describes the development of an interactive computer‐based laboratory manual, created to facilitate the teaching and learning of medical histology. The overarching goal of developing the manual is to facilitate self‐directed group interactivities that actively engage students during laboratory sessions. The design of the manual includes guided instruction for students to navigate virtual slides, exercises for students to monitor learning, and cases to provide clinical relevance. At the end of the laboratory activities, student groups can generate a laboratory report that may be used to provide formative feedback. The instructional value of the manual was evaluated by a questionnaire containing both closed‐ended and open‐ended items. Closed‐ended items using a five‐point Likert‐scale assessed the format and navigation, instructional contents, group process, and learning process. Open‐ended items assessed student's perception on the effectiveness of the manual in facilitating their learning. After implementation for two consecutive years, student evaluation of the manual was highly positive and indicated that it facilitated their learning by reinforcing and clarifying classroom sessions, improved their understanding, facilitated active and cooperative learning, and supported self‐monitoring of their learning. Anat Sci Educ 6: 342–350. © 2013 American Association of Anatomists.     

Quantifying the interdisciplinarity of scientific journals and fields

There is an overall perception of increased interdisciplinarity in science, but this is difficult to confirm quantitatively owing to the lack of adequate methods to evaluate subjective phenomena. This is no different from the difficulties in establishing quantitative relationships in human and social sciences. In this paper we quantified the interdisciplinarity of scientific journals and science fields by using an entropy measurement based on the diversity of the subject categories of journals citing a specific journal. The methodology consisted in building citation networks using the Journal Citation Reports^® database, in which the nodes were journals and edges were established based on citations among journals. The overall network for the 11-year period (1999–2009) studied was small-world and followed a power-law with exponential cutoff distribution with regard to the in-strength. Upon visualizing the network topology an overall structure of the various science fields could be inferred, especially their interconnections. We confirmed quantitatively that science fields are becoming increasingly interdisciplinary, with the degree of interdisplinarity (i.e. entropy) correlating strongly with the in-strength of journals and with the impact factor.     

Level of deprivation does not affect degree of discounting in pigeons

Two experiments tested the effects of food deprivation on discounting in pigeons. An adjusting-amount procedure was used to estimate the subjective value of food at delays ranging from 1 to 24 s. Experiment 1 compared pigeons’ discounting of delayed food reinforcers at 75 %–80 % and 90 %–95 % of free-feeding weight. Experiment 2 compared discounting under 1- and 23-h food deprivation. In both experiments at both deprivation levels, discounting was well described by the hyperboloid discounting function. No systematic effect of level of deprivation on degree of discounting was observed in either experiment. This finding is consistent with the view that pigeons’ choices are controlled by the relative, rather than the absolute, value of reinforcers.     

Viscoelasticity of blood and viscoelastic blood analogues for use in polydymethylsiloxane in vitro models of the circulatory system

The non-Newtonian properties of blood are of great importance since they are closely related with incident cardiovascular diseases. A good understanding of the hemodynamics through the main vessels of the human circulatory system is thus fundamental in the detection and especially in the treatment of these diseases. Very often such studies take place in vitro for convenience and better flow control and these generally require blood analogue solutions that not only adequately mimic the viscoelastic properties of blood but also minimize undesirable optical distortions arising from vessel curvature that could interfere in flow visualizations or particle image velocimetry measurements. In this work, we present the viscoelastic moduli of whole human blood obtained by means of passive microrheology experiments. These results and existing shear and extensional rheological data for whole human blood in the literature enabled us to develop solutions with rheological behavior analogous to real whole blood and with a refractive index suited for PDMS (polydymethylsiloxane) micro- and milli-channels. In addition, these blood analogues can be modified in order to obtain a larger range of refractive indices from 1.38 to 1.43 to match the refractive index of several materials other than PDMS.     

Cognitive Development and Comprehension of Physics Concepts

Summaries

English

The purpose of this study was twofold: (1) to investigate the cognitive development of llth‐grade science students in Jordan; and (2) to investigate the relationship between cognitive development of science students and their comprehension of concrete and formal physics concepts.

The sample of this study consisted of 389 secondary science students (209 males and 180 females) of the school year 1979‐1980. Cognitive development of the students was measured by an Arabic version of the Longeot Test. Comprehension of physics concepts was assessed by an achievement test constructed by the researchers and validated by teachers of physics and the science supervisor in the Irbid district of Jordan.

The study did not reveal any significant difference between males and females in cognitive development. Moreover, it revealed that only 17% of the students were formal thinkers, whereas 52% were concrete thinkers.

The 2×3 ANOVA revealed that cognitive level was a highly significant factor in the comprehension of both concrete and formal concepts. It also revealed that while sex was not a significant factor in the comprehension of concrete concepts, it was a significant factor in the comprehension of formal concepts. The interaction between sex and cognitive level was not significant in the comprehension of both types of concepts.     

Teams’ innovation: getting there through knowledge sharing and absorptive capacity

This study addresses the contribution of knowledge sharing behaviour and absorptive capacity to innovation at team level. Although the hypotheses reflect the dominant literature, the study’s novelty lies in the data collected from several industries in Portugal, avoiding possible industry bias. Relationships are tested outside sectors where traditionally team effects are studied, for example healthcare. Data were collected from 141 employees working in organizational teams, excluding top management teams, which are often the object of research addressing phenomena leading to innovation. There is no evidence in support of organizational size effect, team’s geographic concentration effect or gender effect. However, team tenure duration is positively related to increased knowledge sharing, that is, recent teams do not share as much knowledge as older ones. Structural Equation Modelling was used to test the mediation effect of absorptive capacity between individual knowledge sharing behaviour and team innovation. Evidence in support of full mediation was found.