255 research outputs found

    Does an Information Technology Investment Contribute to Company Performance: a Further Examination of the Productivity Paradox

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    This article continues the discussion examining IT’s contribution on firm performance. Byrnjolfsson (1993) identified what is known as the “productivity paradox” and posited a number of reasons for it. Carr (2003) added fuel by suggesting IT is ubiquitous and provides no significant firm advantage. This study does identify that industry type and size matters. Utilizing the position of CIO, or similar, as a proxy for IT emphasis, the study finds that non-IT intensive organizations, with annual sales less than $101million do achieve performance advantages over firms without an IT emphasis. The implication being that the debate is far from over

    P2X7 is an archaic scavenger receptor recognizing apoptotic neuroblasts in early human neurogenesis

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    The expression and function of P2X7 receptors in adult CNS have been widely studied, however, the roles of these purinergic receptors in human neural development has largely focused on the effects of receptor activation. Previous studies of embryonic and adult rodent neural precursors suggest adenosine triphosphate (ATP), the physiological agonist for P2X receptors, can act as a potent modifier of proliferation, migration and differentiation, mediated via intracellular calcium ([Ca2+]i) signaling. The P2X7 receptor has a ubiquitous distribution in the body but is most abundant on macrophages and microglia where its activation by ATP leads to secretion of proinflammatory cytokines. However, extracellular ATP concentrations in the CNS are usually at sub-micromolar levels suggesting that ATP-induced activation of the P2X7 receptor will not occur under physiological circumstances in the CNS. Another possible role for P2X7 receptors has been suggested by recent work on macrophages and neural precursor cells. In these studies the P2X7 receptor was shown to act as a scavenger receptor i.e. a receptor present on a phagocytotic cell which detects molecules present on the surface of apoptotic cells and facilitates phagocytosis of the apoptotic cell. In a recent study of human neural precursor cells (hNPCs) and neuroblasts isolated from human fetal telencephalons at 16-19 WG, our group showed that both P2X7Rhigh/DCXlow hNPCs and P2X7Rhigh/DCXhigh neuroblasts were capable of phagocytic engulfment of a range of targets including latex beads, apoptotic ReN cells and apoptotic neuroblasts. We found that these neuroblasts and their precursor cells expressed functional P2X7 receptors on their cell surface. Although expression of P2X7 is widespread in the cells of the neuroblast, it is those DCX+ neuroblasts with the highest expression of P2X7 which are actively phagocytic towards an autologous apoptotic neighbour or other phagocytic targets, including latex beads and apoptotic ReNcells. Pre-incubation of P2X7high neuroblasts with ATP or oxidized ATP inhibited phagocytosis of targets by these cells. Moreover siRNA knockdown of P2X7R also inhibited phagocytosis of the apoptotic targets. This review considers this major new role for the P2X7 receptor in early human neurogenesis

    The Lantern Vol. 51, No. 1, Fall 1984

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    • Sky Eyes • Flowerwait • Haiku • Sunwatch • Epitaph of A Tale • How Do You Tell A Child • Vineyard Wind • By The Sea • The Wanderer • In Back of the Real Supermarket in Collegeville • Mitosis • Smoke Dreams • On Humankind Today - A Message • Dragon • The Lull • Finale • The Sun • Three Steps in Life • Seaside • To Mark • To Father • Yesterday - Today • The Stars • The Journey • Our Shared Experience, Miles Away • Coming Home • Blossom • Life is the Teacher • Midnight Stroll in February • Eyes (Karen\u27s Poem) • Your Love • Same Welcome as Odysseus • Europa • Sinn Fein • Idle Dreams • I Can Take A Hint • In Retrospect • Rest • China and Porcelain are One in the Same • Momenthttps://digitalcommons.ursinus.edu/lantern/1125/thumbnail.jp

    The Lantern Vol. 49, No. 2, Spring 1983

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    • Time • The Lantern, 1933-1983 • The Battle • Lady Number 9 • That First Night • Wavering • If I Dared • The Hack • The Beauty of a Rose • H2O • The Island • Library • Unicorns • Prisoner of Myrin • How The Universe Was Won • On Success • I, The Poethttps://digitalcommons.ursinus.edu/lantern/1122/thumbnail.jp

    The Lantern Vol. 50, No. 1, Fall 1983

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    • Reaching for My Dream • All Hail • Appreciation • Egotism • Me (Dedicated to...) • Butterfly • Balloon and Bird • Never Again • Mother • The Deaf Ears • Healing • Distress • Silent Death • Whose Reality Is It Anyway? • To Helen • Luna Llena y Soledad • Saved • Jenny • Slope • A Poem in C Minor • A Birth of Proficiency • The Traveling Man • Competing With the Sea • To R. • The Child • And Besides • An Actress\u27 Demise • A Loving Tribute to Francis • Rapunzel • Memorieshttps://digitalcommons.ursinus.edu/lantern/1123/thumbnail.jp

    Exploring institutional reform of Korean civil service pension: advocacy coalition framework, policy knowledge and social innovation

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    Abstract This paper examines what factors are associated with the 2015 pension reform of Korean civil servant as social innovation. We explore what lessons we can learn from the pension reform in terms of the Advocacy Coalition Framework (ACF) model. The ACF model allows us to identify how the substantial reform is, relying on policy knowledge and entrepreneurs, possible in terms of political and social consensus. It also clearly demonstrates the possibility of systematic pension reform at an appropriate level through social learning and policy learning. Through the ACF model, we review how South Koreas civil servant pension reform act occurred at the end of May 2015. The temporal scope covers from 2009 latest reform, and the 2014s President administrative policy speech that had strongly been showed her will to reform the pension issue to the end of May 2015 when the reform bill enacted. We investigate each advocacy coalition in order to elucidate the actors that constitute the two coalition groups and to scrutinize whether a policy broker had existed in the process. We also attempt to find the relatively stable parameters and external events that affected the reform and also the belief system that shared by two advocacy coalition group. The result clearly shows that the two coalition groups shared their normative beliefs ultimately, for example, the need to change the current civil servants pension system, but, the gap in the numerical change in the policy core belief and secondary belief between the two actors had seemed to be excessively large and uncompromising. A policy broker who can coordinate the interests and interests of stakeholder groups over the government pension reform proposal was desperately needed. Negotiation and leadership of the policy entrepreneurs led to a settlement of the government pension reform proposal at the end of May 2015. Their entrepreneurial activities led to an appropriate level of social consensus on the sustainable reform of pension system through policy knowledge and learning. Further research is required to explore how models of socially innovative forms of governance are created in various pension reforms across various countries. It is also required to examine how policy entrepreneurs use policy knowledge and information for a successful institutional reform through social innovation across various countries

    The Lantern Vol. 50, No. 2, Spring 1984

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    • The Storm • Je ne sais pas • The Ghetious Blastious • An Empty Cradle • The Playing Hands • Battle Hymn • A Limerick • Parting Thoughts • The River • Miss You • De la Tristeza • Two So Special • Time of the Unicorn • The Absence • Thru The Breeze • Is the World Really a Round Ball? • Brother • To Michael • Gravity • Refuge • Der Witwer • Plastic Flowers Never Die • Book on the Shelfhttps://digitalcommons.ursinus.edu/lantern/1124/thumbnail.jp

    Turbulence induced additional deceleration in relativistic shock wave propagation: implications for gamma-ray burst

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    The late afterglow of gamma-ray burst is believed to be due to progressive deceleration of the forward shock wave driven by the gamma-ray burst ejecta propagating in the interstellar medium. We study the dynamic effect of interstellar turbulence on shock wave propagation. It is shown that the shock wave decelerates more quickly than previously assumed without the turbulence. As an observational consequence, an earlier jet break will appear in the light curve of the forward shock wave. The scatter of the jet-corrected energy release for gamma-ray burst, inferred from the jet-break, may be partly due to the physical uncertainties in the turbulence/shock wave interaction. This uncertainties also exist in two shell collisions in the well-known internal shock model proposed for gamma-ray burst prompt emission. The large scatters of known luminosity relations of gamma-ray burst may be intrinsic and thus gamma-ray burst is not a good standard candle. We also discuss the other implications.Comment: accepted for publication in Astrophysics and Space Scienc

    Biosemiotics, politics and Th.A. Sebeok’s move from linguistics to semiotics

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    This paper will focus on the political implications for the language sciences of Sebeok’s move from linguistics to a global semiotic perspective, a move that ultimately resulted in biosemiotics. The paper will seek to make more explicit the political bearing of a biosemiotic perspective in the language sciences and the human sciences in general. In particular, it will discuss the definition of language inherent in Sebeok’s project and the fundamental re-drawing of the grounds of linguistic debate heralded by Sebeok’s embrace of the concept of modelling. Thus far, the political co-ordinates of the biosemiotic project have not really been made explicit. This paper will therefore seek to outline 1. how biosemiotics enables us to reconfigure our understanding of the role of language in culture; 2. how exaptation is central to the evolution of language and communication, rather than adaptation; 3. how communication is the key issue in biosphere, rather than language, not just because communication includes language but because the language sciences often refer to language as if it were mere “chatter”, “tropes” and “figures of speech”; 4. how biosemiotics, despite its seeming “neutrality” arising from its transdisciplinarity, is thoroughly political; 5. how the failure to see the implications of the move from linguistics to semiotics arises from the fact that biosemiotics is devoid of old style politics, which is based on representation (devoid of experience) and “construction of [everything] in discourse” (which is grounded in linguistics, not communication study). In contrast to the post-“linguistic turn” idea that the world is “constructed in discourse”, we will argue that biosemiotics entails a reconfiguration of the polis and, in particular, offers the chance to completely reconceptualise ideology

    The novel object recognition memory: neurobiology, test procedure, and its modifications

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    Animal models of memory have been considered as the subject of many scientific publications at least since the beginning of the twentieth century. In humans, memory is often accessed through spoken or written language, while in animals, cognitive functions must be accessed through different kind of behaviors in many specific, experimental models of memory and learning. Among them, the novel object recognition test can be evaluated by the differences in the exploration time of novel and familiar objects. Its application is not limited to a field of research and enables that various issues can be studied, such as the memory and learning, the preference for novelty, the influence of different brain regions in the process of recognition, and even the study of different drugs and their effects. This paper describes the novel object recognition paradigms in animals, as a valuable measure of cognition. The purpose of this work was to review the neurobiology and methodological modifications of the test commonly used in behavioral pharmacology
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