Active Microrheology of Networks Composed of Semiflexible Polymers. II. Theory and comparison with simulations

Building on the results of our computer simulation (ArXiv cond-mat/0503573)we develop a theoretical description of the motion of a bead, embedded in a network of semiflexible polymers, and responding to an applied force. The theory reveals the existence of an osmotic restoring force, generated by the piling up of filaments in front of the moving bead and first deduced through computer simulations. The theory predicts that the bead displacement scales like x ~ t^alfa with time, with alfa=0.5 in an intermediate- and alfa=1 in a long-time regime. It also predicts that the compliance varies with concentration like c^(-4/3) in agreement with experiment.Comment: 18 pages and 2 figure

‘It stays with you’: multiple evocative representations of dance and future possibilities for studies in sport and physical cultures

This article considers the integration of arts-based representations via poetic narratives together with artistic representation on dancing embodiment so as to continue an engagement with debates regarding multiple forms/representations. Like poetry, visual images are unique and can evoke particular kinds of emotional and visceral responses, meaning that alternative representational forms can resonate in different and powerful ways. In the article, we draw on grandparent-grandchild interactions, narrative poetry, and artistic representations of dance in order to illustrate how arts-based methods might synergise to offer new ways of ‘knowing’ and ‘seeing’. The expansion of the visual arts into interdisciplinary methodological innovations is a relatively new, and sometimes contentious approach, in studies of sport and exercise. We raise concerns regarding the future for more arts-based research in the light of an ever-changing landscape of a neoliberal university culture that demands high productivity in reductionist terms of what counts as ‘output’, often within very restricted time-frames. Heeding feminist calls for ‘slow academies’ that attempt to ‘change’ time collectively, and challenge the demands of a fast-paced audit culture, we consider why it is worth enabling creative and arts-based methods to continue to develop and flourish in studies of sport, exercise and health, despite the mounting pressures to ‘perform’

Doing audio-visual montage to explore time and space: The everyday rhythms of Billingsgate Fish Market

This article documents, shows and analyses the everyday rhythms of Billingsgate, London’s wholesale fish market. It takes the form of a short film based an audio-visual montage of time-lapse photography and sound recordings, and a textual account of the dimensions of market life revealed by this montage. Inspired by Henri Lefebvre’s Rhythmanalysis, and the embodied experience of moving through and sensing the market, the film renders the elusive quality of the market and the work that takes place within it to make it happen. The composite of audio-visual recordings immerses viewers in the space and atmosphere of the market and allows us to perceive and analyse rhythms, patterns, flows, interactions, temporalities and interconnections of market work, themes that this article discusses. The film is thereby both a means of showing market life and an analytic tool for making sense of it. This article critically considers the documentation, evocation and analysis of time and space in this way

Affordances, constraints and information flows as ‘leverage points’ in design for sustainable behaviour

Copyright @ 2012 Social Science Electronic PublishingTwo of Donella Meadows' 'leverage points' for intervening in systems (1999) seem particularly pertinent to design for sustainable behaviour, in the sense that designers may have the scope to implement them in (re-)designing everyday products and services. The 'rules of the system' -- interpreted here to refer to affordances and constraints -- and the structure of information flows both offer a range of opportunities for design interventions to in fluence behaviour change, and in this paper, some of the implications and possibilities are discussed with reference to parallel concepts from within design, HCI and relevant areas of psychology

Co-creation: Moving towards a framework for creating innovation in the triple helix

The objective of the paper is to demonstrate how the theoretical ideas of Service-Dominant Logic (S-D logic) can usefully be applied to innovation through collaboration between university, industry and government. The debate around S-D logic has stimulated much discussion around three areas that are particularly pertinent in considering the co-creation of knowledge within the Triple Helix. The first area relates to understanding the nature of the resources provided by all the parties involved and the process through which they are integrated. The second area relates to interaction between the parties involved. The third and most complex area relates to how value is perceived by the different parties. This discussion leads to a proposed model of the co-creation process and four suggested research agendas: Research Agenda One, relating to the resources supplied by the parties and their integration; Research Agenda Two, concerning the interaction practices that enhance co-creation; Research Agenda Three, exploring what value propositions will motivate the different parties to co-create; and Research Agenda Four, considering how co-creation modifies the resources of the parties involved. A model of the co-creation process that encompasses these four research agendas and provides a conceptual framework to analyse Triple Helix initiatives is proposed. Some practical implications are then discussed, relating to the challenges for researchers in identifying who to co-create with and understanding what value propositions will motivate potential partners

Intercultural ethics: questions of methods in language and intercultural communication

This paper explores how questions of ethics and questions of method are intertwined and unavoidable in any serious study of language and intercultural communication. It argues that the focus on difference and solution orientations to intercultural conflict has been a fundamental driver for theory, data collection and methods in the field. These approaches, the paper argues, have created a considerable consciousness raising industry, with methods, trainings and ‘critical incidents’, which ultimately focus intellectual energy in areas which may be productive in terms of courses and publications but which have a problematic basis in their ethical terrain. Dieser Artikel untersucht wie ethische und methodische Fragen nicht nur ineinander greifen, sondern in keiner ernstzunehmenden Studie ueber Sprache und interkulturelle Kommunikation ausgelassen werden duerfen. Es wird hier argumentiert, dass der Schwerpunkt auf Verschiedenheit und Problemorientierung im interkulturellen Konflikt einen wesentlichen Einfluss auf theoretische Entwicklungen, Datenerhebung und Methoden in diesem Bereich hatte. Dieser Artikel legt auch dar, wie diese Ansaetze eine betraechtliche ‘Bewusstseinsbildungs – Branche' erzeugt haben, mit Methoden, Trainings, und ‘kritischen Interaktionssituationen’, welche letztendlich allen intellektuellen Arbeitseifer auf Bereiche konzentriert hat, die zwar ertragreich sind in Bezug auf Kurse und Publikationen, jedoch eine problematische Grundlage im ethischen Bereich aufweisen

Unscrambling butterfly oogenesis

Background Butterflies are popular model organisms to study physiological mechanisms underlying variability in oogenesis and egg provisioning in response to environmental conditions. Nothing is known, however, about; the developmental mechanisms governing butterfly oogenesis, how polarity in the oocyte is established, or which particular maternal effect genes regulate early embryogenesis. To gain insights into these developmental mechanisms and to identify the conserved and divergent aspects of butterfly oogenesis, we analysed a de novo ovarian transcriptome of the Speckled Wood butterfly Pararge aegeria (L.), and compared the results with known model organisms such as Drosophila melanogaster and Bombyx mori. Results A total of 17306 contigs were annotated, with 30% possibly novel or highly divergent sequences observed. Pararge aegeria females expressed 74.5% of the genes that are known to be essential for D. melanogaster oogenesis. We discuss the genes involved in all aspects of oogenesis, including vitellogenesis and choriogenesis, plus those implicated in hormonal control of oogenesis and transgenerational hormonal effects in great detail. Compared to other insects, a number of significant differences were observed in; the genes involved in stem cell maintenance and differentiation in the germarium, establishment of oocyte polarity, and in several aspects of maternal regulation of zygotic development. Conclusions This study provides valuable resources to investigate a number of divergent aspects of butterfly oogenesis requiring further research. In order to fully unscramble butterfly oogenesis, we also now also have the resources to investigate expression patterns of oogenesis genes under a range of environmental conditions, and to establish their functio

Nonhuman humanitarianism: when ‘AI for good’ can be harmful

Artificial intelligence (AI) applications have been introduced in humanitarian operations in order to help with the significant challenges the sector is facing. This article focuses on chatbots which have been proposed as an efficient method to improve communication with, and accountability to affected communities. Chatbots, together with other humanitarian AI applications such as biometrics, satellite imaging, predictive modelling and data visualisations, are often understood as part of the wider phenomenon of ‘AI for social good’. The article develops a decolonial critique of humanitarianism and critical algorithm studies which focuses on the power asymmetries underpinning both humanitarianism and AI. The article asks whether chatbots, as exemplars of ‘AI for good’, reproduce inequalities in the global context. Drawing on a mixed methods study that includes interviews with seven groups of stakeholders, the analysis observes that humanitarian chatbots do not fulfil claims such as ‘intelligence’. Yet AI applications still have powerful consequences. Apart from the risks associated with misinformation and data safeguarding, chatbots reduce communication to its barest instrumental forms which creates disconnects between affected communities and aid agencies. This disconnect is compounded by the extraction of value from data and experimentation with untested technologies. By reflecting the values of their designers and by asserting Eurocentric values in their programmed interactions, chatbots reproduce the coloniality of power. The article concludes that ‘AI for good’ is an ‘enchantment of technology’ that reworks the colonial legacies of humanitarianism whilst also occluding the power dynamics at play