2,346 research outputs found

    A brief overview of the evolution and main features of the biotechnology industry

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    This paper offers an overview of the origin, evolution and main features of the biotechnology industry, putting particular emphasis on the behaviour of one key actor – the dedicated biotechnology firm. It starts with a brief historical background detailing the origin and dynamics of the industry, which is followed by a more detailed examination of the firms’ strategies, business models and networking behaviour. It concludes with a discussion on the constraints and opportunities faced by firms operating outside the main centres of knowledge production and business in biotechnology, as is the case of dedicated biotechnology firms located in Portugal.FC

    A decision support system for planning promotion time slots

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    We report on the development of a Decision Support System (DSS) to plan the best assignment for the weekly promotion space of a TV station. Each product to promote has a given target audience that is best reached at specific time periods during the week. The DSS aims to maximize the total viewing for each product within its target audience while fulfilling a set of constraints defined by the user. The purpose of this paper is to describe the development and successful implementation of a heuristic-based scheduling software system that has been developed for a major Portuguese TV station.Fundação para a Ciência e a Tecnologia (FCT)- FCT/POCI 2010/FEDER, Projecto POCTI/MAT/61842/2004Estação de Televisão SI

    Non-Equilibrium Modeling of the Fe XVII 3C/3D ratio for an Intense X-ray Free Electron Laser

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    We present a review of two methods used to model recent LCLS experimental results for the 3C/3D line intensity ratio of Fe XVII (Bernitt et al. 2012), the time-dependent collisional-radiative method and the density-matrix approach. These are described and applied to a two-level atomic system excited by an X-ray free electron laser. A range of pulse parameters is explored and the effects on the predicted Fe XVII 3C and 3D line intensity ratio are calculated. In order to investigate the behavior of the predicted line intensity ratio, a particular pair of A-values for the 3C and 3D transitions was chosen (2.22 ×\times 1013^{13} s−1^{-1} and 6.02 ×\times 1012^{12} s−1^{-1} for the 3C and 3D, respectively), but our conclusions are independent of the precise values. We also reaffirm the conclusions from Oreshkina et al.(2014, 2015): the non-linear effects in the density matrix are important and the reduction in the Fe XVII 3C/3D line intensity ratio is sensitive to the laser pulse parameters, namely pulse duration, pulse intensity, and laser bandwidth. It is also shown that for both models the lowering of the 3C/3D line intensity ratio below the expected time-independent oscillator strength ratio has a significant contribution due to the emission from the plasma after the laser pulse has left the plasma volume. Laser intensities above ∼1×1012\sim 1\times 10^{12} W/cm2^{2} are required for a reduction in the 3C/3D line intensity ratio below the expected time independent oscillator strength ratio

    A genetic algorithm approach for the TV self-promotion assignment problem

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    We report on the development of a Genetic Algorithm (GA), which has been integrated into a Decision Support System to plan the best assignment of the weekly self-promotion space for a TV station. The problem addressed consists on deciding which shows to advertise and when such that the number of viewers, of an intended group or target, is maximized. The GA proposed incorporates a greedy heuristic to find good initial solutions. These solutions, as well as the solutions later obtained through the use of the GA, go then through a repair procedure. This is used with two objectives, which are addressed in turn. Firstly, it checks the solution feasibility and if unfeasible it is fixed by removing some shows. Secondly, it tries to improve the solution by adding some extra shows. Since the problem faced by the commercial TV station is too big and has too many features it cannot be solved exactly. Therefore, in order to test the quality of the solutions provided by the proposed GA we have randomly generated some smaller problem instances. For these problems we have obtained solutions on average within 1% of the optimal solution value

    Knowledge access and location decisions in biotechnology: the spatial dimension of social networks

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    DINÂMIA'CET, Dezembro de 2009.This paper addresses the spatial dimension of knowledge sourcing strategies, investigating the role played by social networks on the access to scientific and technological knowledge by new biotechnology firms. Our approach takes into consideration the impact of various forms of proximity - geographical, social, cognitive and organisational - on the development of key relationships, as well as on their use for knowledge acquisition. It enables us to assess the relative importance of local and distant knowledge sources and to explain the entrepreneurs’ decisions in terms of network mobilisation.FC

    Salmonella sp. in edible offal (liver and tongue) from pigs slaughtered for consumption

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    During this study, 120 samples from slaughtered pigs (tongue swabs, n=40; liver swabs, n=40; liver parenchyma, n=40) were collected in a slaughterhouse. Salmonella sp. was isolated using conventional microbiological methods and strains were analyzed using serotyping, antimicrobial susceptibility testing and macrorestriction profiling (MRP) by Pulse Field Gel Electrophoresis (PFGE), to identify clonal relationships and potential contamination sources

    Evidence for engraftment of human bone marrow cells in non-lethally irradiated baboons

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    Background. Prior to organ harvesting, an attempt was made to modulate the donor's immune responses against prospective xenogeneic recipients by infusion of 'recipient-type' bone marrow. Methods. For this purpose, baboons conditioned with total lymphoid irradiation were given 6x108 unmodified human bone marrow cells/kg body weight with no subsequent treatment. Results. Animals survived until they were euthanized at 18 months. Using primers specific for human chorionic gonadotrophin gene, the presence of human DNA was confirmed by polymerase chain reaction in the blood of one animal for up to 18 months after cell transplantation; in the other animal, xenogeneic chimerism became undetectable in the blood at 6 months after bone marrow infusion. However, tissue samples obtained from both animals at the time they were euthanized bad evidence of donor (human) DNA. Additionally, the presence of donor DNA in individually harvested colonies of erythroid and myeloid lineages suggested that infused human bone marrow cells had engrafted across the xenogeneic barrier in both baboons. Conclusions. Bone marrow transplantation from human to baboon leads to establishment of chimerism and modulation of donor-specific immune reactivity, which suggests that this strategy could be reproducibly employed to crease 'surrogate' tolerogenesis in prospective donors for subsequent organ transplantation across xenogeneic barriers

    Entry by research-based spin-offs: the determinants of regional variation

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    Reflecting the increasing number of research based spin-offs (RBSOs) created since the nineties, previous studies focus their analysis on the factors that influence university entrepreneurship. However, empirical studies that investigate the determinants of variation on RBSO creation across regions are scarce. Using a unique self-collected dataset that comprehends the population of RBSOs created in Portugal from 1979 until to 2007 we investigate the intensity of spin-offs creation across regions, by focusing on the characteristics of the universities and the region in which the spin-off is located. Our results suggest that the quality and prestige of the universities located in a municipality, as well as the presence of university-affiliated incubators and/or university research parks have a positive impact on the intensity of RBSO creation. Regarding the regional characteristics, the availability of qualified human capital and the regional demand size seem to exert an important effect on spin-off activity across regions.FC

    Building a bridge: social networks and technological regimes in biotechnology and software

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    The paper investigates the influence of technological regimes on the composition and structure of firms’ knowledge networks. We combine insights from two hitherto unconnected bodies of research: one relating technological regimes with the nature of knowledge; and the other relating knowledge and types of innovation with network configuration. Drawing on this framework, we build a number of propositions on the relationship between firms’ networking behaviour and the regime under which they operate, operationalized at both sector and firm-level. These propositions are explored through empirical research comparing firms operating in two distinct knowledge-intensive sectors, namely biotechnology, which is commonly considered more science-based, and software, thought of as mostly technology-based. As expected, we found that distinct technological regimes affect the knowledge search/exchange process, and thus have an impact upon the network building strategies of the firms. The results also reveal that sector-based technological regimes have a greater explanatory capacity than firm-based regimes that cross sectoral boundaries. The use of different approaches and techniques, together with the combination of sector and firm level analyses, provided a tool that enabled a deeper understanding of the variety of networking behaviours among knowledge-intensive firms.POCI/ESC/60500/2004 e PPCDT/ESC/60500/2004 FC
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