11,363 research outputs found

    A model of the learning process with local knowledge externalities illustrated with an integrated graphical framework

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    In this paper we present a theoretical model of the learning process with knowledge externalities to R&D and other learning inputs within a region, a technological district, an industry or a technological cluster with fast rates of accumulation of new technological knowledge. As there are several definitions of localized technological and learning opportunities (according to the technical space, or to the regional space) and of localized technological knowledge, we can therefore find several possible applications to the generic model. The analysis of the learning firm interacting with a specific region in the production of new technological knowledge is just one of them. The analytical model we develop is amenable to a graphical representation. Thus we provide in the first place a unifying graphical framework, consisting of a four-quadrant picture to analyze the process of knowledge accumulation by learning firms located and operating in a specific region or industry, which simultaneously stresses the nature of the basic learning process and the importance of true knowledge spillovers in the generation of new knowledge. We adopt the following approach to the construction of spillover stocks or pools. First, the magnitude of the state of aggregate knowledge in a region or industry is reconstructed through the historic accumulation of flows of knowledge. Thus, the aggregate level of knowledge can always be updated after every learning loop, or at every moment of discrete time, whose unit of measurement we might assume at the outset of our analysis. Secondly, every firm within a region or industry is treated symmetrically regarding spillover effects and magnitudes. Such statement meaning that the amount of aggregate knowledge borrowed from any available source, either the region or industry under analysis or some other distant region or industry, is regarded as the same by every firm. And finally, we model both the loss of appropriation of benefits from innovation and the distance between different technological bases or regional sources in terms of single parameters, or instantaneous rates of growth, weighting respectively the leakage and the absorption intensities of flows and stocks of knowledge. Several theoretical predictions about the direction and magnitude of the knowledge spillovers can therefore be deducted from parametric changes in the leakage and absorption functions of our model arising from, among other things: - Improvements in information technology and falling communication costs observed in the economic system at general. - Improvements in technological communication systems within specific technological districts. - The establishment of explicit cooperative relations and effective access to the pool of collective knowledge, or instead any improvements of the mutuality and trust conditions, within the group of firms located and operating within a specific region. - The increasing of competitive pressures, or the working of any other mechanism for lowering the appropriation of a firm’s gains from innovation, in an array of industrial sectors. One interesting theoretical result is then derived from our full model. With such purpose in mind, we consider first the existence of a relevant competitive situation where appropriation and communication are both dependent upon the number of receiving and sending firms within the region. Whereas the amount of technological leakage per firm increases with the number of firms effectively operating within the region, ceteris paribus; the extent of absorption per firm also increases with the number of firms effectively communicating within the region, ceteris paribus. Apparently, there is a trade-off between such appropriation conditions and communication conditions. In the long-run, the addition of firms eventually exhausts the net positive effects of taking part in an effective network, and so we can establish an equilibrium number of firms operating in the region.

    Integrated graphical framework accounting for the nature and the speed of the learning process: an application to MNEs strategies of internationalisation of production and R&D investment

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    Existing illustrations of the learning phenomenon either stress the relationship between flows and stocks, neglecting the chronological time variable, or the speed of knowledge accumulation along time, neglecting the nature of the underlying learning process. In this paper we present a graphical depiction stressing, in an explicit way, both the nature of interplay between flows and stocks and the intensity of the learning process. The four-quadrant graphs that we develop overcome considerable simplification in literature by deriving, by construction, a measure of dynamic gains of knowledge following the interplay of stock of scientific and technological knowledge and the flow of effort in R&D. This scheme is then applied to study the internationalisation of production and R&D, which are strategies followed by multinational firms. Two types of innovation – process innovation and product innovation – are therefore studied constructing, in each case, an industry performance measure adequately indexed to the cumulated knowledge stock at a given moment in time. In any case, the dynamic efficiency measure adopted naturally takes into account both the absolute changes in the technology indexes and the time delays to reach them, which are properly discounted. Regarding multinationals strategies - internationalisation of production and R&D investment -, we begin with the question of finding a new location for using a now well developed production technology, and then deal with the problem of selecting a region of excellence in research to take gains of concentration advantages and local externalities.Learning; knowledge; technology; R&D; MNEs

    A Model of the Learning Process with Local Knowledge Externalities Illustrated with an Integrated Graphical Framework

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    We present a unified graphical framework accounting for the nature and impact of spillover effects. The dynamics of the learning process with a specific spillover transfer mechanism can be illustrated by recurring to this four-quadrant picture. In particular, a whole cycle of technological learning is explained with help of such a graphical representation of the basic learning process in the presence of knowledge spillovers. We hypothesize two different functional specifications of spillover exchanges among firms within a local innovation system. Each conceivable shape for the knowledge transfer relationship among firms expresses a possible mode and intensity of information processing arising from technology spillovers. A general proposition regarding the relative efficiency of the two alternative formal models with spillovers effects is derived. The basic models with spillover effects are then extended in several relevant directions.Learning; knowledge; technology spillovers; knowledge externalities; local innovation systems

    Global Science Books: A Tale from the Cuckoo’s Nest

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    Successful storage of protocorm-like bodies of hybrid Cymbidium (Orchidaceae) under low temperature conditions

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    AbstractLow temperatures result in lower metabolic cellular activity, thus slowing down cell division and growth. This is advantageous where a plant scientist might seek to store important germplasm without the risks associated with low temperature storage. In this study, two cold temperatures above freezing, namely 4 and 10°C, were tested to assess for how long PLBs could be preserved without a significant loss in regeneration ability (i.e., the ability to form neo-PLBs). Control treatments were cultured at 25°C on Teixeira Cymbidium (TC) medium at a 16-h photoperiod at a photosynthetic photon flux density (PPFD) of 45ÎŒmolm−2s−1. For the cold treatments, each was replicated in the dark and at low light intensity (12-h photoperiod and a PPFD of 10ÎŒmolm−2s−1). All cultures were sub-cultured six times onto fresh medium every 60days, for approximately 1year. On the 7th subculture, all neo-PLBs were prepared uniformly and replated onto standard TC medium under light conditions described above for the control. 45days after the 7th subculture and just before subcultures 1–6, the number of neo-PLBs per half-PLB was measured. The number of neo-PLBs that formed under different treatments depended strongly on the temperature and light conditions with most neo-PLBs forming under control conditions, although that number dropped significantly as the temperature was dropped to 10°C and then even more to 4°C, the same trend being observed when explants were cultured and subcultured under dim light, with organogenesis being more strongly negatively influenced in darkness. For all low-temperature treatments, as well as the dimmed light and darkness treatments, the number of neo-PLBs increased significantly when recultured, on the 7th subculture, onto control TC medium under control environmental conditions, almost as high as the control values. In contrast, the control values decreased, with significantly fewer neo-PLBs by the 7th subculture relative to the control, indicating that new PLBs should be induced from shoot cultures at least once a year to maintain their vitality

    Anthemideae: advances in tissue culture, genetics and transgenic biotechnology

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    Members of the Anthemideae include important floricultural (cut-flower) and ornamental (pot and garden) crops, as well as plants of medicinal and ethno-pharmacological interest. Despite the use of many of these plants (over 1400 species) in the extraction of important secondary metabolites and essential oils, the greatest emphasis has been on their in vitro tissue culture and micropropagation. Few studies have been conducted on genetic transformation, with those primarily focused on increasing yield of compounds in plants. This review, the first and only available for plants within this Family, highlights all the available literature that exists on Anthemideae (excluding ornamental chrysanthemums) in vitro cell, tissue and organ culture, micropropagation and transformation. Key words: Achillea, Anthemis, Artemisia, Matricaria, Santolina, Tanacetum. African Journal of Biotechnology Vol. 2 (12), pp. 547-556, December 200

    Cabell’s International publishing blacklist: An interview with Kathleen Berryman

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    On January 15, 2017, a blog that was maintained by a US librarian, Jeffrey Beall, was suddenly shut down. That blog was famed for its divisive and controversial content, namely two blacklists that in essence labelled open access journals and publishers as “predatory”. Beall showed that the entries on his lists increased annually, yet several publishing entities that had been blacklisted by Beall felt that they had been unfairly listed, causing, in some cases, reputational damage. In the vacuum that ensued in academic publishing quality control, a few entities tried to fill the gap to serve as a warning to academics. One of the organizations that stepped in was US-based Cabell’s International, which created a blacklist of journals that did not fulfill their established criteria. This brief communication reports on a structured interview that was held in June of 2017 between the author and Kathleen Berryman, Cabell's project manager. Some perspectives on Cabell’s whitelists and blacklists are provided
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