2,244 research outputs found
Outlaw Community Innovations
Recent studies of outlaw communities provide qualitative evidence of their existence and the organisation of the underlying innovation processes. We provide descriptive results from a large scale survey of two online outlaw communities focussing on Microsoft's XBox. In line with previous findings, we identify two types of participants in outlaw communities - user innovators and adopters. Based on 2,256 responses, we find that users modify their XBox mainly to be able to increase the set of available functions of their XBox. Users are also motivated to modify their XBox for the sake of having fun and to conduct pirate behaviour. Finally, the results from our survey suggest that user innovators are largely intrinsically motivated by fun and the intellectual stimulation of writing code for homebrew software
Renormalization Group Study of the soliton mass on the (lambda Phi^4)_{1+1} lattice model
We compute, on the model on the lattice, the soliton
mass by means of two very different numerical methods. First, we make use of a
``creation operator'' formalism, measuring the decay of a certain correlation
function. On the other hand we measure the shift of the vacuum energy between
the symmetric and the antiperiodic systems. The obtained results are fully
compatible.
We compute the continuum limit of the mass from the perturbative
Renormalization Group equations. Special attention is paid to ensure that we
are working on the scaling region, where physical quantities remain unchanged
along any Renormalization Group Trajectory. We compare the continuum value of
the soliton mass with its perturbative value up to one loop calculation. Both
quantities show a quite satisfactory agreement. The first is slightly bigger
than the perturbative one; this may be due to the contributions of higher order
corrections.Comment: 19 pages, preprint DFTUZ/93/0
Economics of education research: a review and future prospects
In this paper we offer an appraisal of the economics of education research area, charting its history as a field and discussing the ways in which economists have contributed both to education research and to education policy-making. In particular, we highlight the theoretical and methodological contributions that economists have made to the field of education during the last 50 years. Despite the success of the economics of education as a field of inquiry, we argue that some of the contributions made by economists could be limited if the economics of education is seen as quite distinct from the other disciplines working in the field of education. In these areas of common interest, economists need to work side by side with the other major disciplines in the field of education if their contribution to the field is to be maximised, particularly in terms of applying improved methodology. We conclude that the study of education acquisition and its economic and social impact in the economics of education research area is very likely to remain a fertile research ground. Acknowledgement
The Role of Spokesperson in Ambiguous and Complex Crises: The CDC and Anthrax
This study evaluates the role of spokespersons in complex organizations facing ambiguous crises. Specifically, the Centers for Disease Control and Preventionâs (CDC) response to the anthrax crisis in 2001 is offered as a case study. A content analysis of the print media coverage of the anthrax crisis reveals that many claiming affiliation with the CDC spoke on behalf of the organization, resulting in what appeared to be a fragmented CDC message. The study concludes that the CDCâs failure to provide a central spokesperson contributed to the ambiguity of the situation
Models for linking hunter retention and recruitment to regulations and game populations
IntroductionDeclining hunter populations across North America present wildlife management agencies with the prospect of declining revenues for wildlife conservation and management and the need for new tools to evaluate management strategies and predict future status of game species and hunters.MethodsHere we present a modeling framework and potential decision support tool for managers to link future hunter population dynamics to regulatory restrictiveness, prey abundance, and harvest success. Our hunter model is parameterized based on the authorsâ judgment and can be used for demonstration purposes. We simulated three scenarios of restricted harvest, moderate harvest and liberal harvest.ResultsOur simulations show that even though liberal harvest predicts higher cumulative license sales revenue, it corresponds with a slight decline in buck abundance over 10 years. In contrast, highly restrictive harvest corresponds with deer population growth, but a near collapse of hunter populations. Our model demonstrates that managers might face tradeoffs between managing for deer population abundance and hunting revenue and clarifies how these factors might affect decision making.DiscussionThe utility of our tool would be dependent on accessing data on hunter retention and recruitment, however, the strength of our paper is in highlighting a new way of thinking about and potentially addressing these potential tradeoffs. Further, these simulations demonstrate that these tools could be used to evaluate management strategies but also highlight uncertainties, establish research priorities, and potentially design an adaptive management framework
Free energy of an SU(2) monopole-antimonopole pair
We present a high-statistic numerical study of the free energy of a
monopole-antimonopole pair in pure SU(2) theory. We find that the
monopole-antimonopole interaction potential exhibits a screened behavior, as
one would expect in presence of a monopole condensate. Screening occurs both in
the low-temperature, confining phase of the theory, and in the high-temperature
deconfined phase, with no evidence of a discontinuity of the screening mass
across the transition. The mass of the object responsible for the screening at
low temperature is approximately twice the established value for the lightest
glueball, indicating a prevalent coupling to glueball excitations. At high
temperature, the screening mass increases. We contrast the behavior of the
quantum system with that of the corresponding classical system, where the
monopole-antimonopole potential is of the Coulomb type.Comment: Latex, 22 pages, 8 figures. A mistake in the computer program
implementing the multihistogram method has been corrected and all the
affected numerical data have been revised. The main conclusions of the paper
are unchanged, but the screening masses turn out somehow larger. (We thank
Philippe de Forcrand for correspondence which helped us find the error.
Probabilistic chemotherapy in knee and hip replacement infection: the place of linezolid
Prosthetic joint infection (PJI) can occur with a wide range of microorganisms and clinical features. After replacement surgery of prosthetic joint, prescription of probabilistic broad-spectrum antimicrobial therapy is usual, while awaiting microbial culture results. The aim of our study was to describe the antibiotic susceptibility of microorganisms isolated from hip and knee PJI. The data were collected to determine the best alternative to the usual combination of piperacillin-tazobactam (TZP) or cefotaxime (CTX) and vancomycin (VAN). Based on a French prospective, multicenter study, we analyzed microbiological susceptibility to antibiotics of 183 strains isolated from patients with confirmed hip or knee PJI. In vitro susceptibility was evaluated: TZP+VAN, TZP+linezolid (LZD), CTX+VAN, and CTX+LZD. We also analyzed resistance to different antibiotics commonly used as oral alternatives. Among the 183 patients with PJI, 62 (34%) had a total knee prosthesis, and 121 (66%) a hip prosthesis. The main identified bacteria were Staphylococcus aureus (32.2% of isolates), coagulase-negative staphylococci (27.3%), Enterobacteriaceae (14.2%), and Streptococcus (13.7%). Infections were polymicrobial for 28 (15.3%) patients. All combinations were highly effective: CTX+VAN, CTX+LZD, TZP+VAN, and TZP+LZD (93.4%, 94%, 98.4%, and 98.9% of all cases respectively). Use of LZD instead of VAN in combination with a broad-spectrum beta-lactam covers almost all of the bacteria isolated in PJI. This association should be considered in probabilistic chemotherapy, as it is particularly easy to use (oral administration and no vancomycin monitoring)
Dynamic prediction in breast cancer:proving feasibility in clinical practice using the TEAM trial
School performance in Australia: is there a role for quasi-markets?
Recent changes to the organisation of Australia's education system have raised the possibility of implementing wide-ranging market reforms. In this article we discuss the scope for introducing reforms similar to the United Kingdom's 'quasi-market' model. We discuss the role of school league tables in providing signals and incentives in a quasi-market. Specifically, we compare a range of unadjusted and model-based league tables of primary school performance in Queensland's public education system. These comparisons indicate that model-based tables which account for socio-economic status and student intake quality vary significantly from the unadjusted tables
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