Revealing ensemble state transition patterns in multi-electrode neuronal recordings using hidden Markov models

In order to harness the computational capacity of dissociated cultured neuronal networks, it is necessary to understand neuronal dynamics and connectivity on a mesoscopic scale. To this end, this paper uncovers dynamic spatiotemporal patterns emerging from electrically stimulated neuronal cultures using hidden Markov models (HMMs) to characterize multi-channel spike trains as a progression of patterns of underlying states of neuronal activity. However, experimentation aimed at optimal choice of parameters for such models is essential and results are reported in detail. Results derived from ensemble neuronal data revealed highly repeatable patterns of state transitions in the order of milliseconds in response to probing stimuli.

A simple device for multiplex ELISA made from melt-extruded plastic microcapillary film

We present a simple device for multiplex quantitative enzyme-linked immunosorbant assays (ELISA) made from a novel melt-extruded microcapillary film (MCF) containing a parallel array of 200µm capillaries along its length. To make ELISA devices different protein antigens or antibodies were immobilised inside individual microcapillaries within long reels of MCF extruded from fluorinated ethylene propylene (FEP). Short pieces of coated film were cut and interfaced with a pipette, allowing sequential uptake of samples and detection solutions into all capillaries from a reagent well. As well as being simple to produce, these FEP MCF devices have excellent light transmittance allowing direct optical interrogation of the capillaries for simple signal quantification. Proof of concept experiments demonstrate both quantitative and multiplex assays in FEP MCF devices using a standard direct ELISA procedure and read using a flatbed scanner. This new multiplex immunoassay platform should find applications ranging from lab detection to point-of-care and field diagnostics.

The cry of the owl: investigating decision-making in a contemporary feature film

This article extends the traditions of style-based criticism through an encounter with the insights that can be gained from engaging with filmmakers at work. By bringing into relationship two things normally thought of as separate: production history and disinterested critical analysis, the discussion aims to extend the subjects which criticism can appreciate as well as providing some insights on the creative process. Drawing on close analysis, on observations made during fieldwork and on access to earlier cuts of the film, this article looks at a range of interrelated decision-making anchored by the reading of a particular sequence. The article examines changes the film underwent in the different stages of production, and some of the inventions deployed to ensure key themes and ideas remained in play, as other elements changed. It draws conclusions which reveal perspectives on the filmmaking process, on collaboration, and on the creative response to material realities. The article reveals elements of the complexity of the process of the construction of image and soundtrack, and extends the range of filmmakers’ choices which are part of a critical dialogue. Has a relationship to ‘Sleeping with half open eyes: dreams and realities in The Cry of the Owl’, Movie: A Journal of Film Criticism, 1, (2010) which provides a broader interpretative context for the enquiry.

Anisotropic films of polypyrrole formed electrochemically using a non-planar dopant

We report the electrochemical preparation of electrically conducting films based on polypyrrole, using 10-camphorsulfonate as the dopant, which exhibit a highly anisotropic molecular organisation. This contrasts with earlier reports, in which anisotropy appeared to be restricted to films prepared using aromatic-based planar dopants. Possible growth mechanisms for these materials to account for the molecular anisotropy are discussed.

Influence of synthesis on the structure of electrochemically prepared electrically conducting polymers

The inherent possibility of structural anisotropy in polypyrrole and other heterocyclic systems is introduced. By selecting the appropriate electrochemical variables including monomer and dopant type this intrinsic molecular anisotropy may be used to prepare films with well defined global anisotropy, in which the planes of the pyrrole rings prefer to lie parallel to the electrode surface. The conditions for obtaining such materials are discussed and some of the effects of these novel anisotropic structures on the resultant properties are highlighted. Attention is directed at charge transport and optical properties.

The effect of dopant molecules on the molecular order of electrically-conducting films of polypyrrole

X-ray scattering curves have been measured for a range of electrochemically-prepared conducting polypyrrole films employing a variety of counterions in aqueous solutions. Films containing counterions based on aromatic rings exhibit an anisotropic molecular organization. The degree of anisotropy is enhanced through the use of highly planar counterions. The electrical conductivity of such films is also improved if the charge/volume ratio of the counterion is maintained at a high level. Polypyrrole films prepared using ‘spherically’ shaped counterions such as SO42− do not display such anisotropic molecular organizations, and exhibit lower electrical conductivities. The competing structural roles of the counterions within these molecular composites are discussed.

Children with Special Educational Needs as film makers: Using digital video to support Understandings of Narrative

The literature has identified issues around transitions among phases for all pupils (Cocklin, 1999) including pupils with special educational needs (SEN) (Morgan 1999, Maras and Aveling 2006). These issues include pupils’ uncertainties and worries about building size and spatial orientation, exposure to a range of teaching styles, relationships with peers and older pupils as well as parents’ difficulties in establishing effective communications with prospective secondary schools. Research has also identified that interventions to facilitate these educational transitions should consider managerial support, social and personal familiarisation with the new setting as well as personalised learning strategies (BECTA 2004). However, the role that digital technologies can play in supporting these strategies or facilitating the role of the professionals such as SENCos and heads of departments involved in supporting effective transitions for pupils with SEN has not been widely discussed. Uses of ICT include passing references of student-produced media presentations (Higgins 1993) and use of photographs of activities attached to a timetable to support familiarisation with the secondary curriculum for pupils with autism (Cumine et al. 1998).