Electrochemical detection of TNT at cobalt phthalocyanine mediated screen-printed electrodes and application to detection of airborne vapours

We describe the use of cobalt phthalocyanine as a mediator to improve the sensitivity for the electrochemical detection of TNT. Commercial screen-printed electrodes containing cobalt phthalocyanine were employed for determination of TNT. Improved sensitivities compared to screen-printed carbon electrodes without phthalocyanine were observed, current response for cyclic voltammetric measurements at modified electrodes being at least double that of unmodified electrodes. A synergistic effect between oxygen and TNT reduction was also observed. Correlation between TNT concentrations and sensor output was observed between 0–200 µM TNT. Initial proof-of-concept experiments combining electrochemical determinations, with the use of an air-sampling cyclone, are also reported

The proneural wave in the Drosophila optic lobe is driven by an excitable reaction-diffusion mechanism.

In living organisms, self-organised waves of signalling activity propagate spatiotemporal information within tissues. During the development of the largest component of the visual processing centre of the Drosophila brain, a travelling wave of proneural gene expression initiates neurogenesis in the larval optic lobe primordium and drives the sequential transition of neuroepithelial cells into neuroblasts. Here, we propose that this 'proneural wave' is driven by an excitable reaction-diffusion system involving epidermal growth factor receptor (EGFR) signalling interacting with the proneural gene l'sc. Within this framework, a propagating transition zone emerges from molecular feedback and diffusion. Ectopic activation of EGFR signalling in clones within the neuroepithelium demonstrates that a transition wave can be excited anywhere in the tissue by inducing signalling activity, consistent with a key prediction of the model. Our model illuminates the physical and molecular underpinnings of proneural wave progression and suggests a generic mechanism for regulating the sequential differentiation of tissues.Wellcome Trust Royal Societ

Where Nothing Happened: The Experience of War Captivity and Levinas’s Concept of the ‘There Is’

This article takes as its subject matter the juridico-political space of the prisoner of war (POW) camp. It sets out to determine the nature of this space by looking at the experience of war captivity by Jewish members of the Western forces in World War II, focusing on the experience of Emmanuel Levinas, who spent 5 years in German war captivity. On the basis of a historical analysis of the conditions in which Levinas spent his time in captivity, it argues that the POW camp was a space of indifference that was determined by the legal exclusion of prisoners from both war and persecution. Held behind the stage of world events, prisoners were neither able to exercise their legal agency nor released from law into a realm of extra-legal violence. Through a close reading of Levinas’s early concept of the ‘there is’ [il y a], the article seeks to establish the impact on prisoners of prolonged confinement in such a space. It sets out how prisoners’ subjectivity dissolved in the absence of meaningful relations with others and identifies the POW camp as a space in which existence was reduced to indeterminate, impersonal being

Adorno?s Grey, Taussig?s Blue: Colour, Organization and Critical Affect

In this article we seek to open up the study of affect and organization to colour. Often simply taken for granted in organizational life and usually neglected in organizational thought, colour is an affective force by default. Deploying and interweaving the languages of affect theory, critical theory, and organization studies, we discuss colour as a primary phenomenon for the study of ?critical affect?. We then trace colour?s affect in conditioning the unfolding of organization in two particular ?colour/spaces? ? Adorno?s grey and Taussig?s blue of our title ? and discuss both its ambiguity and critical potential. Finally, we ponder what colour might do to the style of an organizational scholarship attuned to affect, where sentences blur with things and forces more than they seek to represent them

Opposition and dissidence: two modes of resistance against international rule

Rule is commonly conceptualized with reference to the compliance it invokes. In this article, we propose a conception of rule via the practice of resistance instead. In contrast to liberal approaches, we stress the possibility of illegitimate rule, and, as opposed to critical approaches, the possibility of legitimate authority. In the international realm, forms of rule and the changes they undergo can thus be reconstructed in terms of the resistance they provoke. To this end, we distinguish between two types of resistance - opposition and dissidence - in order to demonstrate how resistance and rule imply each other. We draw on two case studies of resistance in and to international institutions to illustrate the relationship between rule and resistance and close with a discussion of the normative implications of such a conceptualization

Robustness under Functional Constraint: The Genetic Network for Temporal Expression in Drosophila Neurogenesis

Precise temporal coordination of gene expression is crucial for many developmental processes. One central question in developmental biology is how such coordinated expression patterns are robustly controlled. During embryonic development of the Drosophila central nervous system, neural stem cells called neuroblasts express a group of genes in a definite order, which leads to the diversity of cell types. We produced all possible regulatory networks of these genes and examined their expression dynamics numerically. From the analysis, we identified requisite regulations and predicted an unknown factor to reproduce known expression profiles caused by loss-of-function or overexpression of the genes in vivo, as well as in the wild type. Following this, we evaluated the stability of the actual Drosophila network for sequential expression. This network shows the highest robustness against parameter variations and gene expression fluctuations among the possible networks that reproduce the expression profiles. We propose a regulatory module composed of three types of regulations that is responsible for precise sequential expression. This study suggests that the Drosophila network for sequential expression has evolved to generate the robust temporal expression for neuronal specification