808 research outputs found
Universal features in the growth dynamics of complex organizations
We analyze the fluctuations in the gross domestic product (GDP) of 152
countries for the period 1950--1992. We find that (i) the distribution of
annual growth rates for countries of a given GDP decays with ``fatter'' tails
than for a Gaussian, and (ii) the width of the distribution scales as a power
law of GDP with a scaling exponent . Both findings are in
surprising agreement with results on firm growth. These results are consistent
with the hypothesis that the evolution of organizations with complex structure
is governed by similar growth mechanisms.Comment: 4 pages, 7 ps figures, using Latex2e with epsf rotate and multicol
style files. Submitted to PR
Simvastatin inhibits TLR8 signaling in primary human monocytes and spontaneous TNF production from rheumatoid synovial membrane cultures
Simvastatin has been shown to have anti-inflammatory effects that are independent of its serum cholesterol lowering action, but the mechanisms by which these anti-inflammatory effects are mediated have not been elucidated. To explore the mechanism involved, the effect of simvastatin on Toll-like receptor (TLR) signalling in primary human monocytes was investigated. A short pre-treatment with simvastatin dose-dependently inhibited the production of tumor necrosis factor-α (TNF) in response to TLR8 (but not TLRs 2, 4, or 5) activation. Statins are known inhibitors of the cholesterol biosynthetic pathway, but intriguingly TLR8 inhibition could not be reversed by addition of mevalonate or geranylgeranyl pyrophosphate; downstream products of cholesterol biosynthesis. TLR8 signalling was examined in HEK 293 cells stably expressing TLR8, where simvastatin inhibited IKKα/β phosphorylation and subsequent NF-κB activation without affecting the pathway to AP-1. Since simvastatin has been reported to have anti-inflammatory effects in RA patients and TLR8 signalling contributes to TNF production in human RA synovial tissue in culture, simvastatin was tested in these cultures. Simvastatin significantly inhibited the spontaneous release of TNF in this model which was not reversed by mevalonate. Together, these results demonstrate a hitherto unrecognized mechanism of simvastatin inhibition of TLR8 signalling that may in part explain its beneficial anti-inflammatory effects
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The confidence cult(ure)
In this paper we explore how confidence has become a technology of self that invites girls and women to work on themselves. The discussion demonstrates the extensiveness of what we call the ‘cult(ure) of confidence’ across different areas of social life, and examines the continuities in the way that exponents of the confidence cult(ure) name, diagnose and propose solutions to archetypal feminist questions about labour, value and the body. Our analysis focuses on two broad areas of social life in which the notion of confidence has taken hold powerfully in the last few years: popular discussions about gender and work, and consumer body culture. Examining the incitements to self-confidence in these realms, we show how an emergent technology of confidence, systematically re-signifies feminist accounts, by turning away from structural inequalities and collectivist critiques of male domination into heightened modes of self-work and self-regulation, and by repudiating the injuries inflicted by the structures of inequality. We conclude by situating the ‘confidence cult(ure)’ in relation to wider debates about feminism, postfeminism and neoliberalism
Heterogeneity and the dynamics of technology adoption
We estimate the demand for a videocalling technology in the presence of both network effects and heterogeneity. Using a unique dataset from a large multinational firm, we pose and estimate a fully dynamic model of technology adoption. We propose a novel identification strategy based on
post-adoption technology usage to disentangle equilibrium beliefs concerning the evolution of the network from observed and unobserved heterogeneity in technology adoption costs and use benefits. We find that employees have significant heterogeneity in both adoption costs and network benefits, and have preferences for diverse networks. Using our estimates, we evaluate a number of counterfactual adoption policies, and find that a policy of strategically targeting the right subtype for initial adoption can lead to a faster-growing and larger network than a policy of uncoordinated or diffuse adoption
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Scripts people live in the marketplace: an application of script analysis to Confessions of a Shopaholic
This paper shows how Script Analysis can produce new marketing theory by applying it to
contemporary shopping behaviour via British novelist Madeleine Wickham’s novel,
Confessions of a Shopaholic. We show how Becky Bloomwood, the central character, is a
Scripted Shopaholic for whom shopping is the activity around which everything else in her
live falls in and out of place. In presenting a Scripted Shopaholic Racket System, we theorise:
how shopping is used to structure time and relationships with others; the role of injunctions
and attributions and related discounting in fulfilling shopping scripts; and, the possibility of
freedom from excessive shopping scripts. We therefore bring together psychoanalysis, literary
texts, and shopping theories to generate new insights about why people shop (and often shop
too much), and how such behaviours might be transforme
Nigellissima: A Study of Glamour, Performativity and Embodiment
This is a study of glamour, its complexities and its relationship with and role within celebrity culture. We explore glamour in the context of Nigella, the London-born TV cook, food writer and self-proclaimed ‘domestic goddess’ of British culinary culture. In our study we consider the interconnections between glamour, specifically Italian-style retro-glamour, and performativity in Nigella’s career. We also address the role of embodiment and authenticity in the masquerade of femininity. Our analysis focuses on Nigella’s glamour over time, considering its creation, enactment and reaffirmation following scandal. We conclude by speculating on glamour’s complex and ambivalent relationship with celebrity culture, and the role of vulnerability in creating authentic and enduring glamour in contemporary consumer society
A review of multi-component maintenance models with economic dependence
In this paper we review the literature on multi-component maintenance models with economic dependence. The emphasis is on papers that appeared after 1991, but there is an overlap with Section 2 of the most recent review paper by Cho and Parlar (1991). We distinguish between stationary models, where a long-term stable situation is assumed, and dynamic models, which can take information into account that becomes available only on the short term. Within the stationary models we choose a classification scheme that is primarily based on the various options of grouping maintenance activities: grouping either corrective or preventive maintenance, or combining preventive-maintenance actions with corrective actions. As such, this classification links up with the possibilities for grouped maintenance activities that exist in practice
Methodology of calculation of construction and hydrodynamic parameters of a foam layer apparatus for mass-transfer processes
Промислова реалізація методу стабілізації газорідинного шару дозволяє значно розширити галузь застосування пінних апаратів і відкриває нові можливості інтенсифікації технологічних процесів з одночасним створенням маловідходних технологій. У статті встановлені основні параметри, що впливають на гідродинаміку пінних апаратів, розглянуті основні конструкції та режими роботи пінних апаратів. Виявлено зв'язок гідродинамічних параметрів. Розглянуто гідродинамічні закономірності пінного шару. Вказані фактори, що впливають на процес масообміну, як в газовій, так і в рідкій фазах. Проведений аналіз ряду досліджень показав, що перспективним напрямком інтенсифікації процесу масообміну є розробка апаратів з трифазним псевдозрідженим шаром зрошуваної насадки складних форм із сітчастих матеріалів. Отже, необхідне проведення спеціальних досліджень гідродинамічних режимів роботи апарату з сітчастою насадкою і визначенням параметрів, що впливають на швидкість переходу насадки з одного режиму в інший.Industrial implementation of the stabilization method of the gas-liquid layer can significantly expand the field of use of foaming apparatus and opens up new opportunities for intensifying technological processes with the simultaneous creation of low-waste technologies. The article establishes the basic parameters influencing the hydrodynamics of foam apparatus, considers the basic constructions and operating modes of foam apparatus. The connection of hydrodynamic parameters is revealed. The hydrodynamic laws of the foam layer are considered. The indicated factors affecting the process of mass transfer, both in the gas and in the liquid phases. The conducted analysis of a number of studies showed that the perspective direction of intensification of the mass transfer process is the development of apparatuses with a three-phase fluidized bed of an irrigated nozzle of complex forms with mesh materials
What benefit-risk trade-offs are acceptable to rheumatoid arthritis patients during treatment selection? Evidence from a multicountry choice experiment
Objective Understanding preferences of patients with rheumatoid arthritis (RA) can facilitate tailored patient-centric care. This study elicited trade-offs that patients with RA were willing to make during treatment selection. Methods Patients with RA completed an online discrete choice experiment, consisting of a series of choices between hypothetical treatments. Treatment attributes were selected based on literature review and qualitative patient interviews. Eligible patients were ≥18 years old, diagnosed with RA, receiving systemic disease-modifying antirheumatic drug therapy, and residents of Europe or USA. Male patients were oversampled for subgroup analyses. Data were analysed using a correlated mixed logit model. Results Of 2090 participants, 42% were female; mean age was 45.2 years (range 18-83). Estimated effects were significant for all attributes (p<0.001) but varied between patients. Average relative attribute importance scores revealed different priorities (p<0.001) between males and females. While reducing pain and negative effect on semen parameters was most important to males, females were most concerned by risk of blood clots and serious infections. No single attribute explained treatment preferences by more than 30%. Preferences were also affected by patients' age: patients aged 18-44 years placed less importance on frequency and mode of treatment administration (p<0.05) than older age groups. Patients were willing to accept higher risk of serious infections and blood clots in exchange for improvements in pain, daily activities or administration convenience. However, acceptable trade-offs varied between patients (p<0.05). Conclusion Treatment preferences of patients with RA were individual-specific, but driven by benefits and risks, with no single attribute dominating the decision-making.</p
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