We propose a scheme for achieving widefield coherent anti-Stokes Raman scattering (CARS) microscopy images with sub-diffraction-limited resolution. This approach adds structured illumination to the widefield CARS configuration [Applied Physics Letters 84, 816 (2004)]. By capturing a number of images at different phases of the standing wave pattern, an image with up to three times the resolution of the original can be constructed. We develop a theoretical treatment of this system and perform numerical simulations for a typical CARS system, which indicate that resolutions around 120 nm are obtainable with the present scheme. As an imaging system, this method combines the advantages of sub-diffraction-limited resolution, endogenous contrast generation, and a wide field of view.

The psychoanalytical case history was in many ways the pivot point of John Forrester’s reflections on case-based reasoning. Yet the Freudian case is not without its own textual forebears. This article closely analyses texts from two earlier case-writing traditions in order to elucidate some of the negotiations by which the case history as a textual form came to articulate the mode of reasoning that we now call ‘thinking in cases’. It reads Eugène Azam’s 1876 observation of Félida X and her ‘double personality’—the case that brought both Azam and Félida to prominence in late 19th-century French science—against a medico-surgical case penned by the Bordeaux physician in the same decade. While the stylistics of Azam’s medical case mirror its epistemic underpinnings in the ‘vertical’ logics of positivist science, the multiple narratives interwoven in Félida’s case grant both Azam and his patient the role of knowledge-making actors in the text. This narrative transformation chimes with the way Azam reasons ‘horizontally’ from particulars to Félida’s singular condition, but sits in tension with his choice to structure the observation along a ‘vertical’ axis. Between the two, we glimpse the emergence of the psychological observation as a mode of writing and thus of thinking in cases.

This article interrogates the way/s in which rival schools studying hypnotism in late nineteenth-century France framed what counts as valid evidence for the purposes of science. Concern over the scientific reality of results is particularly situated in the notion of simulation (the faking of results); the respective approaches to simulation of the Salpêtrière and Nancy schools are analysed through close reading of key texts: Binet and Féré for the Salpêtrière, and Bernheim for Nancy. The article reveals a striking divergence between their scientific frames, which helps account for the bitterness of the schools' disputes. It then explores Bernheim's construction of scientific authority in more detail, for insights into the messiness entailed by theorizing hypnotism in psychical terms, while also attempting to retain scientific legitimacy. Indicative of this messiness, it is argued, is the way in which Bernheim's (apparently inconsistent) approach draws on multiple epistemic frames.

Multiple filamentation in a high concentration solution of coumarin 153 in ethanol is studied. It is shown that the output filament pattern may be controlled by placing diffractive elements (circular aperture, edge) in the input beam path. These filaments are formed in highly reproducible arrays along diffraction maxima corresponding to the element used. Experimental results are supported by numerical simulations. They confirm that diffraction-induced intensity gradients swamp modulational instability on the wavefront, forcing filaments to form along diffraction maxima. The effect of two-photon absorption by coumarin molecules on filament patterns is also investigated over a range of dye concentrations. Control results are finally exploited in the production of arrays of localized lasing filaments, which should open novel applications. The resultant lasing sources are mutually coherent and highly repeatable from shot-to-shot, as is shown by their far-field interference patterns