885 resultados para Sources of knowledge
Resumo:
Knowledge of the long-term history of the perennial ice is an important issue that has eluded study because the Cenozoic core material needed has been unavailable until the recent Arctic Coring Expedition (ACEX). Detrital Fe oxide mineral grains analyzed by microprobe from the last 14 Ma (164 m) of the ACEX composite core on the Lomonosov Ridge were matched to circum-Arctic sources with the same mineral and 12-element composition. These precise source determinations and estimates of drift rates were used to determine that these sand grains could not be rafted to the ACEX core site in less than a year. Thus the perennial ice cover has existed since 14 Ma except for the unlikely rapid return to seasonal ice between the average sampling interval of about 0.17 Ma. Both North America and Russia contributed significant Fe grains to the ACEX core during the last 14 Ma.
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Multilevel theories integrate individual-level processes with those occurring at the level of the firm and above to generate richer and more complete explanations of IB phenomena than the traditional specification of IB relationships as single-level and parsimonious allows. Case study methods permit the timely collection of multiple sources of data, in context, from multiple individuals and multiple organizational units. Further, because the definitions for each level emerge from case data rather than being imposed a priori, case analysis promotes an understanding of deeper structures and cross-level processes. This paper considers the example of sport as an internationalized service to illustrate how the case method might be used to illuminate the multilevel phenomena of knowledge.
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A quasi-biotic model of knowledge evolution has been applied to manufacturing technology capability development which includes product design and development and manufacturing process/workflow improvement. The concepts of “knowledge genes” and “knowledge body” are introduced to explain the evolution of technological capability. It is shown that knowledge development within the enterprise happens as a result of interactions between an enterprise’s internal knowledge and that acquired from external sources catalysed by: (a) internal mechanisms, recources and incentives, and (b) actions and policies of external agencies. A matrix specifying factors contributing to knowledge development and types of manufacturing capabilities (product design, equipment development or use, and workflow) is developed to explain technological knowledge development. The case studies of Tianjin Pipe Corporation (TPCO) and Tianjin Tianduan Press Co. are presented to illustrate the application of the matrix.
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This paper explains how dynamic client portfolios can be a source of ambidexterity (i.e., exploration and exploitation) for knowledge-intensive firms (KIFs). Drawing from a unique qualitative dataset of firms in the global reinsurance market, we show how different types of client relationships underpin a dynamic client portfolio and become a source of ambidexterity for a KIF. We develop a process model to show how KIFs attain knowledge by segmenting their client portfolios, use that knowledge to explore and exploit within and across their client relationships, and dynamically adjust their client portfolios over time. Our study contributes to the literature on external sources of ambidexterity and dynamic management of client knowledge within KIFs.
Resumo:
Provision of information and behavioural instruction has been demonstrated to improve recovery after surgery. However, patients draw on a range of information sources and it is important to establish which sources patients use and how this influences perceptions and behaviour as they progress along the surgical pathway. In this qualitative, exploratory and longitudinal study, the use of information and instruction were explored from the perspective of people undergoing inguinal hernia repair surgery. Seven participants undergoing inguinal hernia repair surgery were interviewed using semi-structured interviews 2 weeks before surgery and 2 weeks and 4 months post-surgery. Nineteen interviews were conducted in total. Topic guides included sources of knowledge, reasons for help-seeking and opting for surgery and factors influencing return to activity. Data were analysed thematically according to Interpretative Phenomenological Analysis. Participants sought information from a range of sources, focusing on informal information sources before surgery and using information and instruction from health-care professionals post-surgery. This information influenced behaviours including deciding to undergo surgery, use of pain medication and returning to usual activity. Anxiety and help-seeking resulted when unexpected post-surgical events occurred such as extensive bruising. Findings were consistent with psychological and sociological theories. Overall, participants were positive about the information and instruction they received but expressed a desire for more timely information on post-operative adverse events.
Resumo:
Knowledge accessing from external organisations is important to firms, especially entrepreneurial ones which often cannot generate internally all the knowledge necessary for innovation. There is, however, a lack of evidence concerning the association between the evolution of firms and the evolution of their networks. The aim of this paper is to begin to fill this gap by undertaking an exploratory analysis of the relationship between the vintage of firms and their knowledge sourcing networks. Drawing on an analysis of firms in the UK, the paper finds some evidence of a U-shaped relationship existing between firm age and the frequency of accessing knowledge from certain sources. Emerging entrepreneurial firms tend to be highly active with regard to accessing knowledge for a range of sources and geographic locations, with the rate of networking dropping somewhat during the period of peak firm growth. For instance, it is found that firms tend to less frequently access knowledge sources such as universities and research institutes in their own region during a stage of peak turnover growth. Overall, the results suggest a complex relationship between the lifecycle of the firm and its networking patterns. It is concluded that policymakers need to become more aware that network formation and utilisation by firms is likely to vary dependent upon their lifecycle position.
Resumo:
Given their central role in mercury (Hg) excretion and suitability as reservoirs, bird feathers are useful Hg biomonitors. Nevertheless, the interpretation of Hg concentrations is still questioned as a result of a poor knowledge of feather physiology and mechanisms affecting Hg deposition. Given the constraints of feather availability to ecotoxicological studies, we tested the effect of intraindividual differences in Hg concentrations according to feather type (body vs. flight feathers), position in the wing and size (mass and length) in order to understand how these factors could affect Hg estimates. We measured Hg concentration of 154 feathers from 28 un-moulted barn owls (Tyto alba), collected dead on roadsides. Median Hg concentration was 0.45 (0.076–4.5) mg kg-1 in body feathers, 0.44 (0.040–4.9) mg kg-1 in primary and 0.60 (0.042–4.7) mg kg-1 in secondary feathers, and we found a poor effect of feather type on intra-individual Hg levels. We also found a negative effect of wing feather mass on Hg concentration but not of feather length and of its position in the wing. We hypothesize that differences in feather growth rate may be the main driver of between-feather differences in Hg concentrations, which can have implications in the interpretation of Hg concentrations in feathers. Finally, we recommend that, whenever possible, several feathers from the same individual should be analysed. The five innermost primaries have lowest mean deviations to both betweenfeather and intra-individual mean Hg concentration and thus should be selected under restrictive sampling scenarios.
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MEGAGEO - Moving megaliths in the Neolithic is a project that intends to find the provenience of lithic materials in the construction of tombs. A multidisciplinary approach is carried out, with researchers from several of the knowledge fields involved. This work presents a spatial data warehouse specially developed for this project that comprises information from national archaeological databases, geographic and geological information and new geochemical and petrographic data obtained during the project. The use of the spatial data warehouse proved to be essential in the data analysis phase of the project. The Redondo Area is presented as a case study for the application of the spatial data warehouse to analyze the relations between geochemistry, geology and the tombs in this area.
Resumo:
This study investigates the practices involved in the production of knowledge about menopause at Caism, Unicamp, a reference center for public policies for women's health. Gynecological appointments and psychological support meetings were observed, and women and doctors were interviewed in order to identify what discourse circulates there and how different actors are brought in to ensure that the knowledge produced attains credibility and travels beyond the boundaries of the teaching hospital to become universal. The analysis is based on localized studies aligned with social studies of science and technology.
Resumo:
This study investigates the practices involved in the production of knowledge about menopause at Caism, Unicamp, a reference center for public policies for women's health. Gynecological appointments and psychological support meetings were observed, and women and doctors were interviewed in order to identify what discourse circulates there and how different actors are brought in to ensure that the knowledge produced attains credibility and travels beyond the boundaries of the teaching hospital to become universal. The analysis is based on localized studies aligned with social studies of science and technology.
Resumo:
The aim of the current study was to describe the sources of variation of energy and nutrient intake and to calculate the number of repetitions of diet measurements to estimate usual intake in adolescents from São Paulo, Brazil. Data was collected using 24-hour dietary recalls (24hR) in 273 adolescents between 2007 and 2008. Individuals completed a repeat 24hR around two months later. The sources of variation were estimated using the random effect model. Variance ratios (within-person to between-person variance ratio) and the number of repetitions of 24hR to estimate usual intake were calculated. The principal source of variation was due to within-person variance. The contribution of day of week and month of year was less than 8%. Variations ranged from 1.15 for calcium to 7.31 for vitamin E. The number of 24hR repeats required to estimate usual intake varied according to nutrient and gender, numbering 15 for males and 8 for females.
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In order to analyze the pollen resources used by the orchid bee Euglossa annectans, samples of larval provisions from cells under construction were taken from 12 different trap nests (wooden boxes) on Santa Catarina Island, southern Brazil. The 43 samples collected between 2002 and 2005 represented all months except December. Overall, 74 pollen types from 24 families were distinguished. Among the 26 pollen types that reached more than 10% in monthly means, the families Melastomataceae, Bromeliaceae, Ochnaceae, Fabaceae, and Myrtaceae were most frequently represented. The Shannon-Weaver diversity index H' for the 43 brood cells varied from 0.10-1.65 and the annual diversity was 0.98. Similarity indices ranged from 0 to 0.87 and were highest during spring and summer. The results characterize E. annectans as a polylectic species. Based on these data, we can conclude that Euglossa females may act as pollinators of many forest species.
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This work examines the sources of moisture affecting the semi-arid Brazilian Northeast (NEB) during its pre-rainy and rainy season (JFMAM) through a Lagrangian diagnosis method. The FLEXPART model identifies the humidity contributions to the moisture budget over a region through the continuous computation of changes in the specific humidity along back or forward trajectories up to 10 days period. The numerical experiments were done for the period that spans between 2000 and 2004 and results were aggregated on a monthly basis. Results show that besides a minor local recycling component, the vast majority of moisture reaching NEB area is originated in the south Atlantic basin and that the nearby wet Amazon basin bears almost no impact. Moreover, although the maximum precipitation in the ""Poligono das Secas'' region (PS) occurs in March and the maximum precipitation associated with air parcels emanating from the South Atlantic towards PS is observed along January to March, the highest moisture contribution from this oceanic region occurs slightly later (April). A dynamical analysis suggests that the maximum precipitation observed in the PS sector does not coincide with the maximum moisture supply probably due to the combined effect of the Walker and Hadley cells in inhibiting the rising motions over the region in the months following April.
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The quantification of sources of carbonaceous aerosol is important to understand their atmospheric concentrations and regulating processes and to study possible effects on climate and air quality, in addition to develop mitigation strategies. In the framework of the European Integrated Project on Aerosol Cloud Climate Interactions (EUCAARI) fine (D(p) < 2.5 mu m) and coarse (2.5 mu m < Dp < 10 mu m) aerosol particles were sampled from February to June (wet season) and from August to September (dry season) 2008 in the central Amazon basin. The mass of fine particles averaged 2.4 mu g m(-3) during the wet season and 4.2 mu g m(-3) during the dry season. The average coarse aerosol mass concentration during wet and dry periods was 7.9 and 7.6 mu g m(-3), respectively. The overall chemical composition of fine and coarse mass did not show any seasonality with the largest fraction of fine and coarse aerosol mass explained by organic carbon (OC); the average OC to mass ratio was 0.4 and 0.6 in fine and coarse aerosol modes, respectively. The mass absorbing cross section of soot was determined by comparison of elemental carbon and light absorption coefficient measurements and it was equal to 4.7 m(2) g(-1) at 637 nm. Carbon aerosol sources were identified by Positive Matrix Factorization (PMF) analysis of thermograms: 44% of fine total carbon mass was assigned to biomass burning, 43% to secondary organic aerosol (SOA), and 13% to volatile species that are difficult to apportion. In the coarse mode, primary biogenic aerosol particles (PBAP) dominated the carbonaceous aerosol mass. The results confirmed the importance of PBAP in forested areas. The source apportionment results were employed to evaluate the ability of global chemistry transport models to simulate carbonaceous aerosol sources in a regional tropical background site. The comparison showed an overestimation of elemental carbon (EC) by the TM5 model during the dry season and OC both during the dry and wet periods. The overestimation was likely due to the overestimation of biomass burning emission inventories and SOA production over tropical areas.
Resumo:
Biomass burning is an important source of atmospheric Particulate Matter (PM) in Brazil: the burning of forests in the northwest and of sugar cane plantations in the southeast are important examples. The objective of this work is the measurement of the PM emission profile of burning of sugar cane and other characteristic vegetative burning in the region of Sao Carlos-SP/Brazil. Samples of PM(10) and PM(2.5) were collected in different conditions, including small laboratory controlled burnings and real ones. The samples were analysed by X-Ray Fluorescence (XRF) and 14 chemical elements quantified. t-Student tests were performed to compare the obtained profiles, using as a reference a vegetative burn profile taken from the USEPA data bank SPECIATE. All measured profiles presented significant amounts of Cl and K, which are confirmed as tracers of sugar cane foliage burning.