Femtosecond laser micro-inscription of optical coherence tomography resolution test artifacts

Optical coherence tomography (OCT) systems are becoming more commonly used in biomedical imaging and, to enable continued uptake, a reliable method of characterizing their performance and validating their operation is required. This paper outlines the use of femtosecond laser subsurface micro-inscription techniques to fabricate an OCT test artifact for validating the resolution performance of a commercial OCT system. The key advantage of this approach is that by utilizing the nonlinear absorption a three dimensional grid of highly localized point and line defects can be written in clear fused silica substrates.

Material artifacts:practices for doing strategy with 'stuff'

This paper addresses the dearth of research into material artifacts and how they are engaged in strategizing activities. Building on the strategy-as-practice perspective, and the notion of epistemic objects, we develop a typology of strategy practices that show how managers use material artifacts to strategize by a dual process of knowledge abstraction and substitution. Empirically, we study the practice of underwriting managers in reinsurance companies. Our findings first identify the artifacts – pictures, maps, data packs, spreadsheets and graphs – that these managers use to appraise reinsurance deals. Second, the analysis of each artifact’s situated use led to the identification of five practices for doing strategy with artifacts: physicalizing, locating, enumerating, analyzing, and selecting. Last, we developed a typology that shows how practices vary in terms of their level of abstraction from the physical properties of the risk being reinsured and unfold through a process of substituting. Our conceptual framework extends existing work in the strategy-as-practice field that calls for research into the role of material artifacts.

Quantization of the Inhomogeneous Bianchi I model:quasi-Heisenberg picture

The quantization scheme is suggested for a spatially inhomogeneous 1+1 Bianchi I model. The scheme consists in quantization of the equations of motion and gives the operator (so called quasi-Heisenberg) equations describing explicit evolution of a system. Some particular gauge suitable for quantization is proposed. The Wheeler-DeWitt equation is considered in the vicinity of zero scale factor and it is used to construct a space where the quasi-Heisenberg operators act. Spatial discretization as a UV regularization procedure is suggested for the equations of motion.