We describe an experimental methodology for the study of chemical self-organization in micropatterned reaction systems. Our approach is based on office-printer-assisted soft lithography and allows the fabrication of centimeter-scale devices with reactor units as small as 50 µm. The devices are made from the elastomeric material poly(dimethylsiloxane) and are filled with a modified Belousov-Zhabotinsky solution. This excitable reaction-diffusion medium employs 1,4-cyclohexanedione as a bubble-free organic substrate and Fe(II)-[batho(SO 3 ) 2 ] 3 as a high-absorbance redox catalyst/indicator. Chemical wave propagation is affected by the loss of bromine from the aqueous phase into the elastomer matrix. The strength of this activating process depends on the local surface-to-volume ratio and can increase the wave velocity by a factor of 2. For devices with gridlike reactor networks, we observe a pronounced deformation of target patterns and the pinning of spiral waves to single elastomer obstacles as well as to obstacle clusters.

The aim of this research is to describe the development of the Science Teachers’ Pedagogical Discontentment Scale, an instrument that measures the discontentment that arises in teachers as they recognize a mismatch between their own pedagogical beliefs and goals and their actual classroom practices. From a conceptual change perspective, we explore the meaning of pedagogical discontentment and discuss its role in shaping teachers’ receptivity to messages of reform. We present an instrument that can be used to measure teachers’ pedagogical discontentment, an instrument that will allow science educators to better describe the affective states of teachers as they enter professional development experiences. The items for the initial instrument were derived from a series of interviews with practicing teachers; from these interviews, a group of 42 items were designed around a group of five subscales. The final instrument, revised after two rounds of field testing, includes 21 multiple‐choice items clustered around six subscales (subscales derived from interviews with science teachers). The processes used to develop the items and to refine instrument are discussed. Uses for this instrument to inform professional development experiences are explored as well as implications.

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The Science Teachers' Pedagogical Discontentment (STPD) scale has formerly been developed in the United States and used since 2006. Based on the perceptions of selected teachers, the scale is deeply rooted in the cultural and national standards. Given these limitations, the measurement integrity of its scores has not yet been conclusively established internationally, such as in the Saudi Arabia context. The items of the scale are slightly tailored to make the instrument suitable in the specific context, such as with respect to country-based regulations, reforms, and everyday practices of science teachers and their professional development initiatives. Item-based descriptive statistics, the measure's factor structure as opposed to its former validity studies, and factor-based reliability scores are investigated in the present report. Thus, this study extends the validity and reliability measures of the instrument to the international scale and further confirms its appropriateness to measure teacher attitudes towards inquirybased science education initiatives.