Three Keys to Success for Principals (and Their Teachers)

This is the author's accepted manuscript, post peer-review. The publisher's official version is available at: http://dx.doi.org/10.1080/00228958.2008.10516527.What is successful leadership and how can leadership concepts be applied to schools? Hundreds of books and articles and a plethora of executive seminars describe what leadership is and propose strategies for what effective leaders do. Most of these writings and presentations, however, focus on business, with much less information available about how to lead schools. In addition, there is a diversity of opinions about what makes leaders effective. This article suggests that it is possible to extract, reframe, and apply the best of what is known about leadership to help principals be more successful. Moreover, if principals are successful, teachers also are positioned to be successful, with the ultimate impact being successful student learning

Supramolecular approach to new inkjet printing inks

Electronically complementary, low molecular weight polymers that self-assemble through tunable π−π stacking interactions to form extended supramolecular polymer networks have been developed for inkjet printing applications and successfully deposited using three different printing techniques. Sequential overprinting of the complementary components results in supramolecular network formation through complexation of π-electron rich pyrenyl or perylenyl chain-ends in one component with π-electron deficient naphthalene diimide residues in a chain-folding polyimide. The complementary π−π stacked polymer blends generate strongly colored materials as a result of charge-transfer absorption bands in the visible spectrum, potentially negating the need for pigments or dyes in the ink formulation. Indeed, the final color of the deposited material can be tailored by varying the end-groups of the π-electron rich polymer component. Piezoelectric printing techniques were employed in a proof of concept study to allow characterization of the materials deposited, and a thermal inkjet printer adapted with imaging software enabled in situ analysis of the ink drops as they formed and of their physical properties. Finally, continuous inkjet printing allowed greater volumes of material to be deposited, on a variety of different substrate surfaces, and demonstrated the utility and versatility of this novel type of ink for industrial applications

The trade-off between fertility and education : evidence from before the demographic transition

The trade-off between child quantity and quality is a crucial ingredient of unified growth models that explain the transition from Malthusian stagnation to modern growth. We present first evidence that such a trade-off indeed existed already in the nineteenth century, exploiting a unique census-based dataset of 334 Prussian counties in 1849. Furthermore, we find that causation between fertility and education runs both ways, based on separate instrumental-variable models that instrument fertility by sex ratios and education by landownership inequality and distance to Wittenberg. Education in 1849 also predicts the fertility transition in 1880-1905