982 resultados para knowledge source
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We use best practice benchmarking rationales to propose a dynamic research design that accounts for the endogenous components of across-firms heterogeneous routines to study changes in performance and their link to organizational knowledge investments. We thus contribute to the operationalization of management theoretical frameworks based on resources and routines. The research design employs frontier measures that provide industry-level benchmarking in organizational settings, and proposes some new indicators for firm-level strategic benchmarking. A profit-oriented analysis of the U.S. technology industry during 2000-2011 illustrates the usefulness of our design. Findings reveal that industry revival following economic distress comes along with wider gaps between best and worst performers. Second stage analyses show that increasing intangibles stocks is positively associated with fixed target benchmarking, while enhancing R&D spending is linked to local frontier progress. The discussion develops managerial interpretations of the benchmarking measures that are suitable for control mechanisms and reward systems.
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The development and tests of an iterative reconstruction algorithm for emission tomography based on Bayesian statistical concepts are described. The algorithm uses the entropy of the generated image as a prior distribution, can be accelerated by the choice of an exponent, and converges uniformly to feasible images by the choice of one adjustable parameter. A feasible image has been defined as one that is consistent with the initial data (i.e. it is an image that, if truly a source of radiation in a patient, could have generated the initial data by the Poisson process that governs radioactive disintegration). The fundamental ideas of Bayesian reconstruction are discussed, along with the use of an entropy prior with an adjustable contrast parameter, the use of likelihood with data increment parameters as conditional probability, and the development of the new fast maximum a posteriori with entropy (FMAPE) Algorithm by the successive substitution method. It is shown that in the maximum likelihood estimator (MLE) and FMAPE algorithms, the only correct choice of initial image for the iterative procedure in the absence of a priori knowledge about the image configuration is a uniform field.
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OBJECTIVE: HIV-1 post-exposure prophylaxis (PEP) is frequently prescribed after exposure to source persons with an undetermined HIV serostatus. To reduce unnecessary use of PEP, we implemented a policy including active contacting of source persons and the availability of free, anonymous HIV testing ('PEP policy'). METHODS: All consultations for potential non-occupational HIV exposures i.e. outside the medical environment) were prospectively recorded. The impact of the PEP policy on PEP prescription and costs was analysed and modelled. RESULTS: Among 146 putative exposures, 47 involved a source person already known to be HIV positive and 23 had no indication for PEP. The remaining 76 exposures involved a source person of unknown HIV serostatus. Of 33 (43.4%) exposures for which the source person could be contacted and tested, PEP was avoided in 24 (72.7%), initiated and discontinued in seven (21.2%), and prescribed and completed in two (6.1%). In contrast, of 43 (56.6%) exposures for which the source person could not be tested, PEP was prescribed in 35 (81.4%), P < 0.001. Upon modelling, the PEP policy allowed a 31% reduction of cost for management of exposures to source persons of unknown HIV serostatus. The policy was cost-saving for HIV prevalence of up to 70% in the source population. The availability of all the source persons for testing would have reduced cost by 64%. CONCLUSION: In the management of non-occupational HIV exposures, active contacting and free, anonymous testing of source persons proved feasible. This policy resulted in a decrease in prescription of PEP, proved to be cost-saving, and presumably helped to avoid unnecessary toxicity and psychological stress.
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The COMPTEL unidentified source GRO J1411-64 was observed by INTEGRAL, and its central part, also by XMM-Newton. The data analysis shows no hint for new detections at hard X-rays. The upper limits in flux herein presented constrain the energy spectrum of whatever was producing GRO J1411-64, imposing, in the framework of earlier COMPTEL observations, the existence of a peak in power output located somewhere between 300-700 keV for the so-called low state. The Circinus Galaxy is the only source detected within the 4$\sigma$ location error of GRO J1411-64, but can be safely excluded as the possible counterpart: the extrapolation of the energy spectrum is well below the one for GRO J1411-64 at MeV energies. 22 significant sources (likelihood $> 10$) were extracted and analyzed from XMM-Newton data. Only one of these sources, XMMU J141255.6-635932, is spectrally compatible with GRO J1411-64 although the fact the soft X-ray observations do not cover the full extent of the COMPTEL source position uncertainty make an association hard to quantify and thus risky. The unique peak of the power output at high energies (hard X-rays and gamma-rays) resembles that found in the SED seen in blazars or microquasars. However, an analysis using a microquasar model consisting on a magnetized conical jet filled with relativistic electrons which radiate through synchrotron and inverse Compton scattering with star, disk, corona and synchrotron photons shows that it is hard to comply with all observational constrains. This and the non-detection at hard X-rays introduce an a-posteriori question mark upon the physical reality of this source, which is discussed in some detail.
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Fortunato Bartolomeo De Felice (1723-1789) fut le maître d'oeuvre de l'Encyclopédie d'Yverdon (1770-1780), une refonte complète et originale de l'Encyclopédie de Diderot et d'Alembert. Inséré dans un vaste réseau scientifique et commercial, De Felice était en relation épistolaire avec de nombreux savants et libraires de l'Europe des Lumières. Restée presque entièrement inédite jusqu'à sa récente publication sous forme électronique, la correspondance de De Felice constitue une véritable mine d'informations : ces lettres apportent un éclairage précieux sur l'encyclopédisme, le marché du livre et la circulation des savoirs à la fin de l'Ancien Régime. La présente étude se propose de montrer en quoi cette riche correspondance documente de manière renouvelée la question des transferts culturels au XVIIIe siècle : à la lumière de cette source exceptionnelle, De Felice apparaît en effet comme un intermédiaire culturel de premier plan.
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Frequently the choice of a library management program is conditioned by social, economic and/or political factors that result in the selection of a system that is not altogether suitable for the library’s needs, characteristics and functions. Open source software is quickly becoming a preferred solution, owing to the freedom to copy, modify and distribute it and the freedom from contracts, as well as for greater opportunities for interoperability with other applications. These new trends regarding open source software in libraries are also reflected in LIS studies, as evidenced by the different courses addressing automated programs, repositorymanagement, including the Linux/GNU operating system, among others. The combination of the needs of the centres and the new trends for open source software is the focus of a virtual laboratory for the use of open source software for library applications. It was the result of a project, whose aim was to make a useful contribution to the library community, that was carried out by a group of professors of the School of Library and Information Science of the University of Barcelona, together with a group of students, members of a Working Group on Open Source Software for Information Professionals, of the Professional Library Association of Catalonia.
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Introduction: Intoxications with colchicine usually occur by ingestion of meadow saffron leaves (Colchicum autumnale) which are mistakenly collected for alimentary purposes instead of the leaves of crow garlic (Allium ursinum). Colchicine, the main alkaloid of Colchicum autumnale, is present in all parts of the plant. We report a rarer source of mistake, i.e. between the flowers of Colchicum autumnale and Crocus sativus. The similarity in this case is limited to the appearance of the flowers, but Colchicum autumnale, which is also flowering in autumn, lacks the crimson stigma from which the saffron spice is derived from Crocus sativus. Case report: A 47-year-old woman collected the stamens of a flower resembling Crocus sativus for use as saffron. Her knowledge about Crocus sativus was limited to having seen this plant previously at a museum of saffron (Mund, Switzerland). She prepared a meal with rice using three pinches of ''saffron'' for ten tablespoons of rice. She and her 8-year-old child, both ate the usual amount of rice (6 and 2 tablespoons, respectively). The 2 brothers (4- and 9-years-old) only ate 3 teaspoons of rice each. A slightly bitter taste and the absence of a yellow colouration were peculiar. Three to four hours after the meal, the mother developed nausea and contacted the Swiss Toxicological Information Centre, suspecting a plant misidentification. All family members were referred to the regional university hospital for administration of oral activated charcoal. No other symptoms were reported, notably no symptoms in the 8-year-old boy and his brothers. Colchicine serum concentration (blood sample obtained 15 hours after ingestion) measured by HPLC-mass spectrometry was 0.36 mg/L for the mother, and 0.13 mg/L for the 8-year-old child, respectively (therapeutic levels: 0.30-2.5 mg/L). Conclusion: This report demonstrates that a significant amount of colchicine may be absorbed even after ingestion of very small quantities of Colchicum autumnale, which in this case was confused with Crocus sativus. Serum colchicine concentrations in the sub-/therapeutic range can be quantified by HPLC-mass spectrometry, which allows a very sensitive and specific detection of this alkaloid in blood and urine.
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Myoblast transfer therapy has been extensively studied for a wide range of clinical applications, such as tissue engineering for muscular loss, cardiac surgery or Duchenne Muscular Dystrophy treatment. However, this approach has been hindered by numerous limitations, including early myoblast death after injection and specific immune response after transplantation with allogenic cells. Different cell sources have been analyzed to overcome some of these limitations. The object of our study was to investigate the growth potential, characterization and integration in vivo of human primary fetal skeletal muscle cells. These data together show the potential for the creation of a cell bank to be used as a cell source for muscle cell therapy and tissue engineering. For this purpose, we developed primary muscular cell cultures from biopsies of human male thigh muscle from a 16-week-old fetus and from donors of 13 and 30 years old. We show that fetal myogenic cells can be successfully isolated and expanded in vitro from human fetal muscle biopsies, and that fetal cells have higher growth capacities when compared to young and adult cells. We confirm lineage specificity by comparing fetal muscle cells to fetal skin and bone cells in vitro by immunohistochemistry with desmin and 5.1 H11 antibodies. For the feasibility of the cell bank, we ensured that fetal muscle cells retained intrinsic characteristics after 5 years cryopreservation. Finally, human fetal muscle cells marked with PKH26 were injected in normal C57BL/6 mice and were found to be present up to 4 days. In conclusion we estimate that a human fetal skeletal muscle cell bank can be created for potential muscle cell therapy and tissue engineering.
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This article examines the extent and limits of nonstate forms of authority in international relations. It analyzes how the information and communication technology (ICT) infrastructure for the tradability of services in a global knowledge-based economy relies on informal regulatory practices for the adjustment of ICT-related skills. By focusing on the challenge that highly volatile and short-lived cycles of demands for this type of knowledge pose for ensuring the right qualification of the labor force, the article explores how companies and associations provide training and certification programs as part of a growing market for educational services setting their own standards. The existing literature on non-conventional forms of authority in the global political economy has emphasized that the consent of actors, subject to informal rules and some form of state support, remains crucial for the effectiveness of those new forms of power. However, analyses based on a limited sample of actors tend toward a narrow understanding of the issues concerned and fail to fully explore the differentiated space in which non state authority is emerging. This article develops a three-dimensional analytical framework that brings together the scope of the issues involved, the range of nonstate actors concerned, and the spatial scope of their authority. The empirical findings highlight the limits of these new forms of nonstate authority and shed light on the role of the state and international governmental organizations in this new context.