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This study fills a gap with TPACK instrumentation by validating a survey instrument for use specifically with secondary mathematics in-service teachers in the United States using an instrument originally developed in Australia (Handal et al., 2012). A comparable national sample was surveyed in the U.S. to the original Australian instrumentation study. Findings revealed the factor structure of the Australian TPACK instrument differed when used in the U.S. and presents a new validated instrument (TPACK-M-US) for use with secondary mathematics in-service teachers in the U.S. We provide three sources of validity evidence (e.g. Instrument or Test Content, Internal Structure, Response Processes). Appropriate uses and interpretations are discussed in addition to the importance of validation research for educational settings. 

To enhance the solubility of orally administered pharmaceuticals, liquid capsules or amorphous tablets are often preferred over crystalline drug products. However, little is known regarding the variation in bonding mechanisms between pharmaceutical molecules in their different disordered forms. In this study, liquid and melt-quenched glassy carbamazepine have been studied using high energy X-ray diffraction and modeled using Empirical Potential Structure Refinement. The results show significant structural differences between the liquid and glassy states. The liquid shows a wide range of structures; from isolated molecules, to aromatic ring correlations and NH-O hydrogen bonding. Upon quenching from the liquid to the glass the number of hydrogen bonds per molecule increases by ~50% at the expense of a ~30% decrease in the close contact (non-bonded) carbon-carbon interactions between aromatic rings. During the cooling process, there is an increase in both singly and doubly hydrogen-bonded adjacent molecules. Although hydrogen-bonded dimers found in the crystalline states persist in the glassy state, the absence of a crystalline lattice also allows small, hydrogen-bonded NH-O trimers and tetramers to form. This proposed model for the structure of glassy carbamazepine is consistent with the results from vibrational spectroscopy and nuclear magnetic resonance. 

A research group at the Max Planck Institute for the History of Science on “Itineraries of Materials, Recipes, Techniques, and Knowledge in the Early Modern World” held a series of workshops (2014–2015) on the movement of knowledge(materials, techniques, objects) across Eurasia, resulting in an edited volume. Participants articulated a framework of “entangled itineraries,” “material complexes,” and “nodes of convergence” by which historians might follow routes ofknowledge-making extending over very long distances and/or great spans of time. The key concepts are (1) “material complex” denoting the constellation of substances, practices, techniques, beliefs, and values that accrete as knowledge around materials; (2) the “relational field,” the social, intellectual, economic, emotional domain formed by a “node of convergence”—often a hub of trade and exchange—within which a material complex crystalizes; and (3) “itineraries,” or the routes taken by materials through which they stabilize and/ or transform. 

Hands-on experimentation did not begin in the natural scientific laboratory of the nineteenth century; it is instead a characteristic part of craft processes wherever and whenever they have been carried out – whether the bronze hearths of the pre-historic Near East, the furniture ateliers of the Ancien Régime, or in the kilns of the Saintonge, where Bernard Palissy labored so hard to imitate porcelain. A contemporary manuscript, BnF Ms. Fr. 640, gives remarkable insight into this constant experimentation of the artisan in the workshop. It also highlights the experimentation on paper that Palissy and other craftspeople engaged in during the sixteenth century. 

Through a close reading and reconstruction of technical recipes for ephemeral artworks in a manuscript compiled in Toulouse ca. 1580 (BnF MS Fr. 640), we question whether ephemeral art should be treated as a distinct category of art. The illusion and artifice underpinning ephemeral spectacles shared the aims and, frequently, the materials and techniques of art more generally. Our analysis of the manuscript also calls attention to other aspects of art making that reframe consideration of the ephemeral, such as intermediary processes, durability, the theatrical and transformative potential of materials, and the imitation and preservation of lifelikeness. 

An anonymous author in late 16th-century France recorded 370 pages of art and technical recipes, among which are two especially puzzling entries: one for a medicine from the "east" that involved smoking rosemary in a pipe (a new medicinal device in the 16th century that had come to Europe from North America), and another for closing silkworms in a vessel in order to produce a gold powder. This essay traces these processes across Eurasia, and explores how such movement of medicinal and alchemical knowledge could occur across such long spans of distance and time.