4,418 research outputs found
The influence of âtopic and resourceâ on some aspects of social theorising
Developments in sociological theory since the 1960s have been responses to disciplinary problems rather than changes in fashion. The problem of topic and resourceâwhere sociology has to use everyday understandings and practices as study resources even though they are legitimate topics of enquiryâhas been an important and sometimes neglected spur to many of these developments. The turn to discourse, conversation analysis and the rise of Bourdieu's reflexivity are all attempts to address the problem, but each is shown to be unsatisfactory in different ways. In summary, they seek to address the issue as requiring either a principled methodological or a principled theoretical solution, and neither approach is capable of comprehensively addressing the matter. It is argued that these âsolutionsâ depend, in turn, on one of two particular construals of what the âproblemâ consists in, neither of which is necessary or coherent. Each, it is argued, depends on a philosophical trick: making language out to need formal improvement (the Bertrand Russell trick) or introducing inappropriate scepticism to everyday life (the RenĂ© Descartes trick). It is suggested that treating topic and resource not as a problem but as something which opens up new areas of investigation successfully deflates the issue and avoids unnecessary theoretical and methodological contortions
Neural Network Model for Apparent Deterministic Chaos in Spontaneously Bursting Hippocampal Slices
A neural network model that exhibits stochastic population bursting is
studied by simulation. First return maps of inter-burst intervals exhibit
recurrent unstable periodic orbit (UPO)-like trajectories similar to those
found in experiments on hippocampal slices. Applications of various control
methods and surrogate analysis for UPO-detection also yield results similar to
those of experiments. Our results question the interpretation of the
experimental data as evidence for deterministic chaos and suggest caution in
the use of UPO-based methods for detecting determinism in time-series data.Comment: 4 pages, 5 .eps figures (included), requires psfrag.sty (included
Size-Dependent Transition to High-Dimensional Chaotic Dynamics in a Two-Dimensional Excitable Medium
The spatiotemporal dynamics of an excitable medium with multiple spiral
defects is shown to vary smoothly with system size from short-lived transients
for small systems to extensive chaos for large systems. A comparison of the
Lyapunov dimension density with the average spiral defect density suggests an
average dimension per spiral defect varying between three and seven. We discuss
some implications of these results for experimental studies of excitable media.Comment: 5 pages, Latex, 4 figure
Fluctuations in the Site Disordered Traveling Salesman Problem
We extend a previous statistical mechanical treatment of the traveling
salesman problem by defining a discrete "site disordered'' problem in which
fluctuations about saddle points can be computed. The results clarify the basis
of our original treatment, and illuminate but do not resolve the difficulties
of taking the zero temperature limit to obtain minimal path lengths.Comment: 17 pages, 3 eps figures, revte
The Conformal Penrose Limit and the Resolution of the pp-curvature Singularities
We consider the exact solutions of the supergravity theories in various
dimensions in which the space-time has the form M_{d} x S^{D-d} where M_{d} is
an Einstein space admitting a conformal Killing vector and S^{D-d} is a sphere
of an appropriate dimension. We show that, if the cosmological constant of
M_{d} is negative and the conformal Killing vector is space-like, then such
solutions will have a conformal Penrose limit: M^{(0)}_{d} x S^{D-d} where
M^{(0)}_{d} is a generalized d-dimensional AdS plane wave. We study the
properties of the limiting solutions and find that M^{(0)}_{d} has 1/4
supersymmetry as well as a Virasoro symmetry. We also describe how the
pp-curvature singularity of M^{(0)}_{d} is resolved in the particular case of
the D6-branes of D=10 type IIA supergravity theory. This distinguished case
provides an interesting generalization of the plane waves in D=11 supergravity
theory and suggests a duality between the SU(2) gauged d=8 supergravity of
Salam and Sezgin on M^{(0)}_{8} and the d=7 ungauged supergravity theory on its
pp-wave boundary.Comment: 20 pages, LaTeX; typos corrected, journal versio
SOME PROPERTIES OF THE KERR SOLUTION TO LOW ENERGY STRING THEORY
The Kerr solution to axidilaton gravity is analyzed in the
Debney--Kerr--Schild formalism. It is shown that the Kerr principal null
congruence retains its property to be geodesic and shear free, however, the
axidilatonic Kerr solution is not algebraically special. A limiting form of
this solution is considered near the ring-like Kerr singularity. This limiting
solution coincides with the field around a fundamental heterotic string
obtained by Sen.Comment: 14 pages., LaTe
The Claims Culture: A Taxonomy of Industry Attitudes
This paper presents an analysis of a familiar aspect of construction industry culture that we have dubbed 'the claims culture'. This is a culture of contract administration that lays a strong emphasis on the planning and management of claims. The principal elements of the analysis are two sets of distinctions. The first comprises economic and occupational orders, referring to two kinds of control that are exercised over the construction process; predicated respectively on economic ownership and occupational competence. The second refers to contrasting attitudes towards relationships and problem solving within these orders: respectively 'distributive' and 'integrative'. The concepts of economic and occupational order entail further sub-categories. The various attitudes associated with these categories and sub-categories are described. They are assessed as to their consequences for change initiatives in the industry
Towards practice-based studies of HRM: an actor-network and communities of practice informed approach
HRM may have become co-terminus with the new managerialism in the rhetorical orthodoxies of the HRM textbooks and other platforms for its professional claims. However, we have detailed case-study data showing that HR practices can be much more complicated, nuanced and indeed resistive toward management within organizational settings.
Our study is based on ethnographic research, informed by actor-network theory and community of practice theory conducted by one of the authors over an 18-month period. Using actor-network theory in a descriptive and critical way, we analyse practices of managerial resistance, enrolment and counter-enrolment through which an unofficial network of managers used a formal HRM practice to successfully counteract the official strategy of the firm, which was to close parts of a production site. As a consequence, this network of middle managers effectively changed top management strategy and did so through official HRM practices, coupled with other actor-network building processes, arguably for the ultimate benefit of the organization, though against the initial views of the top management.
The research reported here, may be characterized as a situated study of HRM-in-practice and we draw conclusions which problematize the concept of HRM in contemporary management literature
Drosophila melanogaster as a model for lead neurotoxicology and toxicogenomics research
Drosophila melanogaster is an excellent model animal for studying the neurotoxicology of lead. It has been known since ancient Roman times that long-term exposure to low levels of lead results in behavioral abnormalities, such as what is now known as attention deficit hyperactivity disorder (ADHD). Because lead alters mechanisms that underlie developmental neuronal plasticity, chronic exposure of children, even at blood lead levels below the current CDC community action level (10 ÎŒg/dl), can result in reduced cognitive ability, increased likelihood of delinquency, behaviors associated with ADHD, changes in activity level, altered sensory function, delayed onset of sexual maturity in girls, and changes in immune function. In order to better understand how lead affects neuronal plasticity, we will describe recent findings from a Drosophila behavioral genetics laboratory, a Drosophila neurophysiology laboratory, and a Drosophila quantitative genetics laboratory who have joined forces to study the effects of lead on the Drosophila nervous system. Studying the effects of lead on Drosophila nervous system development will give us a better understanding of the mechanisms of Pb neurotoxicity in the developing human nervous system
Restricted feedback control of one-dimensional maps
Dynamical control of biological systems is often restricted by the practical
constraint of unidirectional parameter perturbations. We show that such a
restriction introduces surprising complexity to the stability of
one-dimensional map systems and can actually improve controllability. We
present experimental cardiac control results that support these analyses.
Finally, we develop new control algorithms that exploit the structure of the
restricted-control stability zones to automatically adapt the control feedback
parameter and thereby achieve improved robustness to noise and drifting system
parameters.Comment: 29 pages, 9 embedded figure
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