565 research outputs found

    Knowledge Diffusion in R&D Groups: The Impact of Internet Technologies

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    Knowledge Diffusion in R&D Groups: The Impact of Internet Technologies

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    Knowledge flows are the lifeblood of any R&D organisation. These firms are increasingly discovering that the knowledge they require is often located beyond their boundaries. In this paper, we investigate how R&D groups acquire and diffuse external knowledge and the role Internet technologies play in this process. The focus of our study is on the technological gatekeeper. Previous studies have found that gatekeepers are key nodes in the innovation process. These sporadic individuals have the skills to identify useful knowledge outside the firm and disseminate this among their local colleagues. However, much of the seminal gatekeeper research has been conducted over two decades ago. In the time since, there have been huge advances in ICT and especially Internet technologies. These technologies have dramatically altered how knowledge workers source and share their information. Our objective is to advance the gatekeeper theory into an era where the knowledge worker is saturated with information. Using case study methods, we examine knowledge flows in the R&D group of an Irish medical devices firm. Our results indicate that due to advances in Internet technology, the traditional gatekeeper no longer exists to any great extent. Instead, the modern R&D lab acquires and diffuses external knowledge through a combination of a ‘web gatekeeper’ and a ‘knowledge transformer.

    Parental Co‐Construction of 5‐ to 13‐Year‐Olds\u27 Global Self‐Esteem Through Reminiscing About Past Events

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    The current study explored parental processes associated with children\u27s global self‐esteem development. Eighty 5‐ to 13‐year‐olds and one of their parents provided qualitative and quantitative data through questionnaires, open‐ended questions, and a laboratory‐based reminiscing task. Parents who included more explanations of emotions when writing about the lowest points in their lives were more likely to discuss explanations of emotions experienced in negative past events with their child, which was associated with child attachment security. Attachment was associated with concurrent self‐esteem, which predicted relative increases in self‐esteem 16 months later, on average. Finally, parent support also predicted residual increases in self‐esteem. Findings extend prior research by including younger ages and uncovering a process by which two theoretically relevant parenting behaviors impact self‐esteem development

    O(a^2) cutoff effects in lattice Wilson fermion simulations

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    In this paper we propose to interpret the large discretization artifacts affecting the neutral pion mass in maximally twisted lattice QCD simulations as O(a^2) effects whose magnitude is roughly proportional to the modulus square of the (continuum) matrix element of the pseudoscalar density operator between vacuum and one-pion state. The numerical size of this quantity is determined by the dynamical mechanism of spontaneous chiral symmetry breaking and turns out to be substantially larger than its natural magnitude set by the value of Lambda_QCD.Comment: 38 pages, 1 figure, 2 table

    Co-Seismic Displacements of the 1994 Northridge, California, Earthquake

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    The 17 January 1994 Northridge, California, earthquake significantly deformed the Earth's crust in the epicentral region. Displacements of 66 survey stations determined from Global Positioning System (GPS) observations collected before and after the earthquake show that individual stations were uplifted by up to 417 ± 5 mm and displaced horizontally by up to 216 ± 3 mm. Using these displacements, we estimate parameters of a uniform-slip model. Fault geometry and slip are estimated independent of seismological information, using Monte Carlo optimization techniques that minimize the model residuals. The plane that best fits the geodetic data lies 1 to 2 km above the plane indicated by aftershock seismicity. Modeling for distributed slip on a coplanar, yet larger model fault indicates that a high-slip patch occurred up-dip and northwest of the mainshock hypocenter and that less than 1 m of slip occurred in the uppermost 5 km of the crust. This finding is consistent with the lack of clear surface rupture and with the notion that the intersection with the fault that ruptured in 1971 formed the up-dip terminus of slip in the Northridge earthquake. Displacements predicted by either of these simple models explain most of the variance in the data within 50 km of the epicenter. On average, however, the scatter of the residuals is twice the data uncertainties, and in some areas, there is significant systematic misfit to either model. The co-seismic contributions of aftershocks are insufficient to explain this mismatch, indicating that the source geometry is more complicated than a single rectangular plane

    Decision and Discovery in Defining “Disease”

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    This version (May 17, 2005) was published in its final form as: Schwartz PH. Decision and discovery in defining 'disease'. In: Kincaid H, McKitrick J, editors. Establishing medical reality: essays in the metaphysics and epistemology of biomedical science. Dordrecht: Springer; 2007. p. 47-63. http://dx.doi.org/10.1007/1-4020-5216-2_5The debate over how to analyze the concept of disease has often centered on the question of whether to include a reference to values, in particular the ‘disvalue’of diseases, or whether to avoid such notions. ‘Normativists,’such as King ([1954], 1981) and Culver and Gert (1982) emphasize the undesirability of diseases, while ‘Naturalists,’ most prominently Christopher Boorse (1977, 1987, 1997), instead require just the presence of biological dysfunction. The debate between normativism and naturalism often deteriorates into stalemate, with each side able to point out significant problems with the other. It starts to look as if neither approach can work. In this paper, I argue that the standoff stems from deeply questionable assumptions that have been used to formulate the opposing positions and guide the debate. In the end, I propose an alternative set of guidelines that offer a more constructive way to devise and compare theories

    Pulsed Feedback Defers Cellular Differentiation

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    Environmental signals induce diverse cellular differentiation programs. In certain systems, cells defer differentiation for extended time periods after the signal appears, proliferating through multiple rounds of cell division before committing to a new fate. How can cells set a deferral time much longer than the cell cycle? Here we study Bacillus subtilis cells that respond to sudden nutrient limitation with multiple rounds of growth and division before differentiating into spores. A well-characterized genetic circuit controls the concentration and phosphorylation of the master regulator Spo0A, which rises to a critical concentration to initiate sporulation. However, it remains unclear how this circuit enables cells to defer sporulation for multiple cell cycles. Using quantitative time-lapse fluorescence microscopy of Spo0A dynamics in individual cells, we observed pulses of Spo0A phosphorylation at a characteristic cell cycle phase. Pulse amplitudes grew systematically and cell-autonomously over multiple cell cycles leading up to sporulation. This pulse growth required a key positive feedback loop involving the sporulation kinases, without which the deferral of sporulation became ultrasensitive to kinase expression. Thus, deferral is controlled by a pulsed positive feedback loop in which kinase expression is activated by pulses of Spo0A phosphorylation. This pulsed positive feedback architecture provides a more robust mechanism for setting deferral times than constitutive kinase expression. Finally, using mathematical modeling, we show how pulsing and time delays together enable “polyphasic” positive feedback, in which different parts of a feedback loop are active at different times. Polyphasic feedback can enable more accurate tuning of long deferral times. Together, these results suggest that Bacillus subtilis uses a pulsed positive feedback loop to implement a “timer” that operates over timescales much longer than a cell cycle

    Russell-names: an introduction to Millian descriptivism

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    This essay studies the semantic properties of what I call Russell-names. Russell-names bear intimate semantic relations with descriptive conditions, in consonance with the main tenets of descriptivism. Yet, they are endowed with the semantic properties attributed to ordinary proper names by Millianism: they are rigid and non-indexical devices of direct reference. This is not an essay in natural language semantics, and remains deliberately neutral with respect to the question whether any among the expressions we ordinarily classify as proper names behave as Russell-names. Its aim is rather that of casting a new light on the traditional debate about descriptivism on the one hand, and, on the other, what is commonly understood as a radically anti-descriptivist approach. From the viewpoint of descriptivism, the conceivability of Russell-names provides welcome relief from the pressure exerted by considerations at odds with a flaccid and/or indexical treatment of proper names. Conversely, from a Millian standpoint, the conceivability of Russell-names indicates that the Millian stance, far from providing a meagre picture of names as ‘mere tags’, is at least in principle consistent with the recognition of their semantic bonds with richer descriptive material. The Appendix provides a formal treatment of Russell-names within a model theoretic semantics for indexical intensional languages, developed within an original ‘double-context’ framework
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