Pore REconstruction and Segmentation (PORES) method for improved porosity quantification of nanoporous materials

Electron tomography is currently a versatile tool to investigate the connection between the structure and properties of nanomaterials. However, a quantitative interpretation of electron tomography results is still far from straightforward. Especially accurate quantification of pore-space is hampered by artifacts introduced in all steps of the processing chain, i.e., acquisition, reconstruction, segmentation and quantification. Furthermore, most common approaches require subjective manual user input. In this paper, the PORES algorithm “POre REconstruction and Segmentation” is introduced; it is a tailor-made, integral approach, for the reconstruction, segmentation, and quantification of porous nanomaterials. The PORES processing chain starts by calculating a reconstruction with a nanoporous-specific reconstruction algorithm: the Simultaneous Update of Pore Pixels by iterative REconstruction and Simple Segmentation algorithm (SUPPRESS). It classifies the interior region to the pores during reconstruction, while reconstructing the remaining region by reducing the error with respect to the acquired electron microscopy data. The SUPPRESS reconstruction can be directly plugged into the remaining processing chain of the PORES algorithm, resulting in accurate individual pore quantification and full sample pore statistics. The proposed approach was extensively validated on both simulated and experimental data, indicating its ability to generate accurate statistics of nanoporous materials

A Computer Algebra Primer and Homework Exercises for use in an Intermediate Macroeconomics Course – A Student/Teacher Collaboration

We discuss using computer algebras systems (CAS) in an undergraduate intermediate macroeconomics class. The criteria used in choosing a CAS are considered. One criterion was that students would bear little or no financial. The lessons learned in implementing a CAS – things that worked well and those that did not work so well – are noted. We also discuss the need for communications with information technology staff for successful implementation. Copyright Springer Science+Business Media, Inc. 2005computer algebra systems, undergraduate education, intermediate macroeconomics,

Characterizing Roman Artifacts to Investigate Gendered Practices in Contexts Without Sexed Bodies

This article concerns the characterization of Roman artifacts so that they can play a greater role in gendered approaches to Roman sites—sites that constitute lived spaces but lack actual references to sexed bodies. It commences with a brief discussion on gendered approaches in the two main strands of Roman archaeology—classical and provincial. Within the differing frameworks of the wider disciplines of classics and archaeology, both strands focus on contexts with sexed bodies—burials, figurative representation, and inscriptions. The discussion serves as a background for more integrated and more interrogative approaches to relationships between Roman artifacts and gendered practices, approaches that aim to develop interpretative tools for investigating social practice in contexts where no representational or biologically sexed bodies are evident. Three types of artifacts—brooches, glass bottles, and needles—are used to demonstrate how differing degrees of gender associations of artifacts and artifact assemblages can provide insights into gender relationships in settlement contexts. These insights in turn contribute to better understandings of gendered sociospatial practices across the Roman world