5,478 research outputs found

    The Role of Narrative Fiction and Semi-Fiction in Organizational Studies

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    In this chapter, we discuss the use of narrative fiction and semi-fiction in organizational research and explore the strengths and weaknesses of these alternative approaches. We begin with an introduction reviewing the existing literature and clarifying what we mean by fiction and semi-fiction. We then present and discuss examples of fiction and semi-fiction focusing on how these approaches can be used in organizational research. We argue that fiction is more useful as a source of data and as a way of representing theory to an audience. Semi-fiction, on the other hand, provides a novel approach to the production and representation of theory. In both cases, researchers face a number of challenges, but also gain access to new and powerful techniques for developing insights into organizational topics

    Text me! New consumer practices and change in organizational fields

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    While scholars have provided increasingly well-developed theoretical frameworks for understanding the role of institutional entrepreneurs and other purposeful actors in bringing about change in organizational fields, much less attention has been paid to the role of unorganized, nonstrategic actors in catalyzing change. In particular, the role of consumers remains largely uninvestigated. In this article, we draw on a case of the introduction of text messaging in the United Kingdom to explore the role of consumers in catalyzing change in organizational fields. Text messaging has become a widely diffused and institutionalized communication practice, in part changing mobile telephony from a voice-based, aural, and synchronous experience to a text-based, visual, and asynchronous experience. As consumers innovated and diffused new practices around this product, their actions led to significant changes in the field. We suggest how and under what conditions consumers are likely to innovate at the micro level and, with the subsequent involvement of other actors, catalyze change at the field level. Our primary contribution is to show how the cumulative effect of the spontaneous activities of one important and particularly dispersed and unorganized group can lead to changes in a field. By showing how change can result from the uncoordinated actions of consumers accumulating and converging over time, we provide an alternative explanation of change in organizational fields that does not privilege purposeful actors such as institutional entrepreneurs

    Randomised, controlled trial of alternating pressure mattresses compared with alternating pressure overlays for the prevention of pressure ulcers : PRESSURE (pressure relieving support surfaces) trial

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    Objective To compare whether differences exist between alternating pressure overlays and alternating pressure mattresses in the development of new pressure ulcers, healing of existing pressure ulcers, and patient acceptability. Design Pragmatic, open, multicentre, randomised controlled trial. Setting 11 hospitals in six NHS trusts. Participants 1972 people admitted to hospital as acute or elective patients. Interventions Participants were randomised to an alternating pressure mattress (n = 982) of- an alternating pressure overlay (n = 990). Main outcome measures The proportion of participants developing a new pressure ulcer of grade 2 or worse; time to development of new pressure ulcers; proportions of participants developing a new ulcer within 30 days; healing of existing pressure ulcers; and patient acceptability Results Intention to treat analysis found no difference in the proportions of participants developing a new pressure ulcer of grade 2 or worse (10.7% overlay patients, 10.3% mattress patients; difference 0.4%, 95% confidence interval - 23% to 3.1%, P = 0.75). More overlay patients requested change owing to dissatisfaction (23.3%) than mattress patients (18.9%, P = 0.02). Conclusion No difference was found between alternating pressure mattresses and alternating pressure overlays in the proportion of people who develop a pressure ulcer

    Structure-based stabilization of insulin as a therapeutic protein assembly via enhanced aromatic-aromatic interactions

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    Key contributions to protein structure and stability are provided by weakly polar interactions, which arise from asymmetric electronic distributions within amino acids and peptide bonds. Of particular interest are aromatic side chains whose directional π-systems commonly stabilize protein interiors and interfaces. Here, we consider aromatic-aromatic interactions within a model protein assembly: the dimer interface of insulin. Semi-classical simulations of aromatic-aromatic interactions at this interface suggested that substitution of residue TyrB26 by Trp would preserve native structure while enhancing dimerization (and hence hexamer stability). The crystal structure of a [TrpB26]insulin analog (determined as a T3Rf3 zinc hexamer at a resolution of 2.25 Å) was observed to be essentially identical to that of WT insulin. Remarkably and yet in general accordance with theoretical expectations, spectroscopic studies demonstrated a 150-fold increase in the in vitro lifetime of the variant hexamer, a critical pharmacokinetic parameter influencing design of long-acting formulations. Functional studies in diabetic rats indeed revealed prolonged action following subcutaneous injection. The potency of the TrpB26-modified analog was equal to or greater than an unmodified control. Thus, exploiting a general quantum-chemical feature of protein structure and stability, our results exemplify a mechanism-based approach to the optimization of a therapeutic protein assembly

    Exact theory of kinkable elastic polymers

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    The importance of nonlinearities in material constitutive relations has long been appreciated in the continuum mechanics of macroscopic rods. Although the moment (torque) response to bending is almost universally linear for small deflection angles, many rod systems exhibit a high-curvature softening. The signature behavior of these rod systems is a kinking transition in which the bending is localized. Recent DNA cyclization experiments by Cloutier and Widom have offered evidence that the linear-elastic bending theory fails to describe the high-curvature mechanics of DNA. Motivated by this recent experimental work, we develop a simple and exact theory of the statistical mechanics of linear-elastic polymer chains that can undergo a kinking transition. We characterize the kinking behavior with a single parameter and show that the resulting theory reproduces both the low-curvature linear-elastic behavior which is already well described by the Wormlike Chain model, as well as the high-curvature softening observed in recent cyclization experiments.Comment: Revised for PRE. 40 pages, 12 figure

    Analysis of Nematic Liquid Crystals with Disclination Lines

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    We investigate the structure of nematic liquid crystal thin films described by the Landau--de Gennes tensor-valued order parameter with Dirichlet boundary conditions of nonzero degree. We prove that as the elasticity constant goes to zero a limiting uniaxial texture forms with disclination lines corresponding to a finite number of defects, all of degree 1/2 or all of degree -1/2. We also state a result on the limiting behavior of minimizers of the Chern-Simons-Higgs model without magnetic field that follows from a similar proof.Comment: 40 pages, 1 figur

    CP--odd Correlation in the Decay of Neutral Higgs Boson into ZZZZ, W+WW^+W^-, or ttˉt{\bar t}

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    We investigate the possibility of detecting CP--odd angular correlations in the various decay modes of the neutral Higgs boson including the modes of a ZZZZ pair, a W+WW^+W^- pair, or a heavy quark pair. It is a natural way to probe the CP character of the Higgs boson once it is identified. Final state interactions (i.e. the absorptive decay amplitude) is not required in such correlations. As an illustrative example we take the fundamental source of the CP nonconservation to be in the Yukawa couplings of the Higgs boson to the heavy fermions. A similar correlation in the process e+el+lHe^+e^- \to l^+ l^- H is also proposed. Our analysis of these correlations will be useful for experiments in future colliders such as LEP II, SSC, LHC or NLC.Comment: 16 pages, plus 8 postscript graphs not posted befor

    Prospective memory: age related change is influenced by APOE genotype

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    Non-focal prospective memory (PM) is sensitive to age-related decline; an additional impairment in focal PM is characteristic of mild stage Alzheimer’s disease. This research explored whether, by mid-adulthood, the distinct demands of focal and non-focal PM expose differences in carriers of an APOE ε4 allele, a genetic risk factor for Alzheimer’s disease. Thirty-three young and 55 mid-age adults, differentiated by APOE genotype, completed a category-decision task with a concurrent focal or non-focal PM demand. Only mid-age ε4 carriers showed a cost of carrying a focal PM intention. In addition, mid-age ε4 carriers showed a significantly greater cost of carrying a non-focal PM intention than young ε4 carriers, supporting a profile of accelerated aging. Consistency in the profile of cost differences observed in mid-age ε4 carriers and pathological aging may indicate premature vulnerability. Future research correlating a shift in PM performance with early genotype differences in brain-based markers of decline is important

    Reduced parahippocampal cortical thickness in subjects at ultra-high risk for psychosis

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    Background: Grey matter volume and cortical thickness represent two complementary aspects of brain structure. Several studies have described reductions in grey matter volume in people at ultra-high risk (UHR) of psychosis; however, little is known about cortical thickness in this group. The aim of the present study was to investigate cortical thickness alterations in UHR subjects and compare individuals who subsequently did and did not develop psychosis. Method: We examined magnetic resonance imaging data collected at four different scanning sites. The UHR subjects were followed up for at least 2 years. Subsequent to scanning, 50 UHR subjects developed psychosis and 117 did not. Cortical thickness was examined in regions previously identified as sites of neuroanatomical alterations in UHR subjects, using voxel-based cortical thickness. Results: At baseline UHR subjects, compared with controls, showed reduced cortical thickness in the right parahippocampal gyrus (p<0.05, familywise error corrected). There were no significant differences in cortical thickness between the UHR subjects who later developed psychosis and those who did not. Conclusions: These data suggest that UHR symptomatology is characterized by alterations in the thickness of the medial temporal cortex. We did not find evidence that the later progression to psychosis was linked to additional alterations in cortical thickness, although we cannot exclude the possibility that the study lacked sufficient power to detect such differences

    The Heavy Photon Search test detector

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    The Heavy Photon Search (HPS), an experiment to search for a hidden sector photon in fixed target electroproduction, is preparing for installation at the Thomas Jefferson National Accelerator Facility (JLab) in the Fall of 2014. As the first stage of this project, the HPS Test Run apparatus was constructed and operated in 2012 to demonstrate the experiment׳s technical feasibility and to confirm that the trigger rates and occupancies are as expected. This paper describes the HPS Test Run apparatus and readout electronics and its performance. In this setting, a heavy photon can be identified as a narrow peak in the e+e− invariant mass spectrum above the trident background or as a narrow invariant mass peak with a decay vertex displaced from the production target, so charged particle tracking and vertexing are needed for its detection. In the HPS Test Run, charged particles are measured with a compact forward silicon microstrip tracker inside a dipole magnet. Electromagnetic showers are detected in a PbW04 crystal calorimeter situated behind the magnet, and are used to trigger the experiment and identify electrons and positrons. Both detectors are placed close to the beam line and split top-bottom. This arrangement provides sensitivity to low-mass heavy photons, allows clear passage of the unscattered beam, and avoids the spray of degraded electrons coming from the target. The discrimination between prompt and displaced e+e− pairs requires the first layer of silicon sensors be placed only 10 cm downstream of the target. The expected signal is small, and the trident background huge, so the experiment requires very large statistics. Accordingly, the HPS Test Run utilizes high-rate readout and data acquisition electronics and a fast trigger to exploit the essentially 100% duty cycle of the CEBAF accelerator at JLab
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