891 resultados para Fractions. Activities. Operations With Fractions
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Includes bibliography
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Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP)
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Costa-Silva JH, Zoccal DB, Machado BH. Chronic intermittent hypoxia alters glutamatergic control of sympathetic and respiratory activities in the commissural NTS of rats. Am J Physiol Regul Integr Comp Physiol 302: R785-R793, 2012. First published December 28, 2011; doi:10.1152/ajpregu.00363.2011.-Sympathetic overactivity and altered respiratory control are commonly observed after chronic intermittent hypoxia (CIH) exposure. However, the central mechanisms underlying such neurovegetative dysfunctions remain unclear. Herein, we hypothesized that CIH (6% O-2 every 9 min, 8 h/day, 10 days) in juvenile rats alters glutamatergic transmission in the commissural nucleus tractus solitarius (cNTS), a pivotal site for integration of peripheral chemoreceptor inputs. Using an in situ working heart-brain stem preparation, we found that L-glutamate microinjections (1, 3, and 10 mM) into the cNTS of control rats (n = 8) evoked increases in thoracic sympathetic nerve (tSN) and central vagus nerve (cVN) activities combined with inhibition of phrenic nerve (PN) activity. Besides, the ionotropic glutamatergic receptor antagonism with kynurenic acid (KYN; 250 mM) in the cNTS of control group (n = 7) increased PN burst duration and frequency. In the CIH group (n = 10), the magnitude of L-glutamate-induced cVN excitation was smaller, and the PN inhibitory response was blunted (P < 0.05). In addition, KYN microinjections into the cNTS of CIH rats (n = 9) did not alter PN burst duration and produced smaller increases in its frequency compared with controls. Moreover, KYN microinjections into the cNTS attenuated the sympathoexcitatory response to peripheral chemoreflex activation in control but not in CIH rats (P < 0.05). These functional CIH-induced alterations were accompanied by a significant 10% increase of N-methyl-D-aspartate receptor 1 (NMDAR1) and glutamate receptor 2/3 (GluR2/3) receptor subunit density in the cNTS (n = 3-8, P < 0.05), evaluated by Western blot analysis. These data indicate that glutamatergic transmission is altered in the cNTS of CIH rats and may contribute to the sympathetic and respiratory changes observed in this experimental model.
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OBJECTIVE: While systemic glucocorticoids compromise bone metabolism, altered intracellular cortisol availability may also contribute to the pathogenesis of primary male osteoporosis (MO). The objective of this study was to assess whether intracellular cortisol availability is increased in MO due to a distorted local cortisol metabolism. METHODS: Forty-one patients with MO were compared with age- and BMI-matched non-osteoporotic subjects after excluding overt systemic hypercortisolism (N = 41). Cortisol, cortisone and the respective tetrahydro-, 5α-tetrahydro- and total cortisol metabolites were analysed by GC-MS in 24 h urine. Apparent 11β-hydroxysteroid dehydrogenase (11β-HSD) enzyme activities, excretion of cortisol metabolites and calcium, and fractional urinary calcium excretion were assessed and related to BMD. RESULTS: Fractional and total urinary calcium excretion negatively correlated with BMD at all (P < 0.05) and at three of five (P < 0.05) measurement sites, respectively. While systemic cortisol was unchanged, apparent 11β-HSD enzyme activity in MO patients (P < 0.01) suggested increased intracellular cortisol availability. Total and fractional urinary calcium excretion was higher, with apparent 11β-HSD enzyme activities consistent with an enhanced intracellular cortisol availability (P < 0.05). CONCLUSION: Apparent 11β-HSD enzyme activities consistent with increased intracellular cortisol availability correlated with urinary calcium loss and reduced bone mineral density in MO. The changes in 11β-HSD activity were associated with both the fractional calcium excretion, suggesting altered renal calcium handling, and the absolute urinary calcium excretion. Both mechanisms could result in a marked bone calcium deficiency if insufficiently compensated for by intestinal calcium uptake.
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Background: Few studies have examined the 20% of individuals who never experience an episode of low back pain (LBP). To date, no investigation has been undertaken that examines a group who claim to have never experienced LBP in their lifetime in comparison to two population-based case–control groups with and without momentary LBP. This study investigates whether LBP-resilient workers between 50 and 65 years had better general health, demonstrated more positive health behaviour and were better able to achieve routine activities compared with both case–control groups. Methods: Forty-two LBP-resilient participants completed the same pain assessment questionnaire as a population-based LBP sample from a nationwide, large-scale cross-sectional survey in Switzerland. The LBP-resilient participants were pairwise compared to the propensity score-matched case controls by exploring differences in demographic and work characteristics, and by calculating odds ratios (ORs) and effect sizes. A discriminant analysis explored group differences, while the multiple logistic regression analysis specified single indicators which accounted for group differences. Results: LBP-resilient participants were healthier than the case controls with momentary LBP and achieved routine activities more easily. Compared to controls without momentary LBP, LBP-resilient participants had a higher vitality, a lower workload, a healthier attitude towards health and behaved more healthily by drinking less alcohol. Conclusions: By demonstrating a difference between LBP-resilient participants and controls without momentary LBP, the question that arises is what additional knowledge can be attained. Three underlying traits seem to be relevant about LBP-resilient participants: personality, favourable work conditions and subjective attitudes/attributions towards health. These rationales have to be considered with respect to LBP prevention.
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As part of the PeECE II mesocosm project, we investigated the effects of pCO2 levels on the initial step of heterotrophic carbon cycling in the surface ocean. The activities of microbial extracellular enzymes hydrolyzing 4 polysaccharides were measured during the development of a natural phytoplankton bloom under pCO2 conditions representing glacial (190 µatm) and future (750 µatm) atmospheric pCO2. We observed that (1) chondroitin hydrolysis was variable throughout the pre-, early- and late-bloom phases, (2) fucoidanase activity was measurable only in the glacial mesocosm as the bloom developed, (3) laminarinase activity was low and constant, and (4) xylanase activity declined as the bloom progressed. Concurrent measurements of microbial community composition, using denaturing-gradient gel electrophoresis (DGGE), showed that the 2 mesocosms diverged temporally, and from one another, especially in the late-bloom phase. Enzyme activities correlated with bloom phase and pCO2, suggesting functional as well as compositional changes in microbial communities in the different pCO2 environments. These changes, however, may be a response to temporal changes in the development of phytoplankton communities that differed with the pCO2 environment. We hypothesize that the phytoplankton communities produced dissolved organic carbon (DOC) differing in composition, a hypothesis supported by changing amino acid composition of the DOC, and that enzyme activities responded to changes in substrates. Enzyme activities observed under different pCO2 conditions likely reflect both genetic and population-level responses to changes occurring among multiple components of the microbial loop.
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Durante la Ilustración, el imperio español alcanzó su máxima amplitud y las instituciones oficiales incrementaron su apoyo a las ciencias. Para defender sus fronteras y ejercer con eficacia el poder político, económico y religioso, la Corona y la Iglesia necesitaban obtener información precisa --incluida la climatológica-- de las posesiones españolas y de los pobladores de éstas. Fueron varios los procedimientos empleados para ello: sistema de cuestionarios y relaciones geográficas, estudios medico-topográficos, visitas e inspecciones oficiales, expediciones político-científicas, correspondencia epistolar, artículos periodísticos, etc. Dichos procedimientos fueron aplicados por redes de informadores cuyas actuaciones se basaban en la división del trabajo, el reparto de colaboradores en diferentes lugares, el uso de códigos de comunicación comprensibles, el envío de los resultados a los superiores jerárquicos y la toma de decisiones por las autoridades competentes. Las redes de información estaban sometidas a dictámenes que normalizaban su creación y continuidad temporal, daban forma a su estructura interna, especificaban sus cometidos y obligaban a cumplir protocolos y plazos. En su seno se idearon planes de investigación integrados en el estudio general de la Tierra, el ser humano y la cultura. El beneficio de las actuaciones de sus miembros se plasmó en cubrir grandes ámbitos geográficos con el consiguiente ahorro de tiempo, esfuerzos y medios. En sus correspondientes contextos, los miembros de las redes efectuaron estudios climatológicos conforme a intereses, imposiciones y circunstancias específicas. Así, los médicos se interesaron por las condiciones climáticas que influían en la salud humana; los funcionarios reales y los ingenieros militares describieron los climas locales y regionales aptos para el fomento y el control político, jurídico y educativo de los habitantes de los territorios hispánicos; los expedicionarios estudiaron las interacciones entre los fenómenos naturales y las influencias de los accidentes geográficos en los climas; los clérigos se interesaron por los aspectos estéticos, apologéticos y contemplativos de los climas; finalmente, en la prensa de la época se publicaron registros meteorológicos periódicos y trabajos climatológicos varios. En definitiva, el saber climatológico en el mundo hispánico ilustrado aportó algunos rasgos esenciales a la climatología en una etapa pre-fundacional de esta disciplina. Dichos rasgos se desarrollaron generalmente en una escala local o regional y se refirieron a los siguientes asuntos: el calor como principal agente de las modificaciones atmosféricas, de la formación de vapor acuoso y de las precipitaciones; la influencia del suelo en el aumento de humedad y calor en el aire; el poder de los vientos para trasladar de un lugar a otro el frío o el calor, el vapor de agua, los fenómenos atmosféricos y los agentes responsables de las enfermedades contagiosas; las propiedades del aire atmosférico y su capacidad para interaccionar con el medio ambiente; la condición estática y repetitiva de los climas, si bien se admitió que dichos fenómenos podían sufrir modificaciones; la corroboración experimental de las diferencias climáticas entre las zonas tropicales y medias del planeta; la refutación de que la naturaleza americana y sus habitantes eran inferiores a los europeos; y la demostración de que los principios rectores de los fenómenos físicos del Viejo y el Nuevo Mundo eran idénticos. Desde el último tercio del siglo XVIII, los documentos producidos por los componentes de las redes de información incluyeron datos meteorológicos. Pero no siempre se emplearon los mismos instrumentos de medida ni se siguieron los mismos protocolos de indagación en idénticas condiciones. Además, y salvo excepciones, los períodos durante los cuales se recabaron datos atmosféricos fueron relativamente cortos, y los expertos no efectuaron las mismas operaciones aritméticas con los parámetros. Por esta razón, y por la orientación utilitaria de los ilustrados hispánicos, el saber climatológico no obtuvo en el período y en el ámbito geográfico considerados resultados teóricos apreciables; en cambio, dio lugar a una gran cantidad de actividades prácticas con aplicaciones a la medicina, la agricultura, la náutica, el fomento, la prevención de riesgos naturales, etc. La principal utilidad de este trabajo consiste en servir de complemento a los procedimientos actualmente en uso en historia de la hidrología y en climatología histórica. ABSTRACT During the Enlightenment, the Spanish Empire achieved its highest length and State institutions increased their support to sciences. In order to defend their frontiers and to exercise political, economical and religious power, the Crown and the Church needed exact information --including the climatologic one-- about its possessions and its habitants. Some of the procedures employed to get that objective were: system of questionnaires and geographic relations, medical-topographic studies, official visits and inspections, political-scientific expeditions, direct mail, journalistic articles, etc. Those procedures were applied by informers´ networks which obtained, manned and transmitted every kind of data about the natural and moral reality of the Hispanic territories; their actions were based on the division of tasks, the distribution of collaborators at several places, the use of understandable communication codes and the sending of results to the hierarchical superiors; after, the competent authorities took decisions. The information networks were subjected to rules witch regulated its creation, temporary continuity, interior structure, objectives, protocols and periods. Their memberships invented plans about the general research of the Earth, the human beings and the culture; and they contributed to get benefits because of covering large geographic frames and economizing time, effort and means. According to their specifics contexts, concerns, impositions and circumstances, the informers performed climatologic tasks. Thus, the physicians were interested in the climatic conditions which affected to human health; the royal officers and military engineers described the most propitious climates to patronage and political, lawful and educative control of inhabitants of Hispanic territories; the participants in politic-scientific expeditions studied the interactions among natural phenomena and the influence of geographic aspects on the climate; the clergymen underlined the esthetic, apologetic and contemplative face of climates; finally, in the newspapers were published a lot of meteorological data and climatologic works. So, the climatologic knowledge in the Hispanic enlightened world added these essential aspects --referred in a local and regional area-- during the pre-foundational epoch of the climatology: the heat as first agent of atmospheric modifications, aqueous vapor and precipitations; the influx of the land in the increment of humidity and heat of the air; the power of the winds to convey the cold, the heat, the aqueous vapor, the atmospheric phenomena and the agents which caused contagious maladies; the properties of the air and its faculty to mediate with the environs; the static and repetitive condition of the climate and its possibility to experience change; the experimental confirmation of climatic varieties between tropical and central areas of the planet; the negation of the inferiority of the American nature and inhabitants; the demonstration about the equality of the rules which conducted physical phenomena in the Old and the New world. Since the last third part of the eighteenth century, the documents produced by the members of the networks included meteorological data. But the informers were not used to employ the same measure instruments and homogeneous protocols completion in the same conditions. Exceptions besides, the times of taking atmospheric data, usually were very short; and the experts did not carry out the same arithmetical operations with parameters. Because of this reason and the utilitarian guidance of the informers, during the Hispanic Enlightenment, it was not possible to obtain theoretic conclusions about climatologic knowledge; but there were a lot of practical activities applied to Medicine, Agriculture, Navigation, patronage, prevention of natural risks, etc. The main utility of this work consist in favoring the present procedures of the History of Hydrology and Historic Climatology.
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We have studied the mechanism of accurate in vitro RNA editing of Trypanosoma brucei ATPase 6 mRNA, using four mRNA-guide RNA (gRNA) pairs that specify deletion of 2, 3, or 4 U residues at editing site 1 and mitochondrial extract. This extract not only catalyzes deletion of the specified number of U residues but also exhibits a novel endonuclease activity that cleaves the input pre-mRNA in a gRNA-directed manner, precisely at the phosphodiester bond predicted in a simple enzymatic model of RNA editing. This cleavage site is inconsistent with a chimera-based editing mechanism. The U residues to be deleted, present at the 3' end of the upstream cleavage product, are then removed evidently by a 3' U-specific exonuclease and not by a reverse reaction of terminal U transferase. RNA ligase can then join the mRNA halves through their newly formed 5' P and 3' OH termini, generating mRNA faithfully edited at the first editing site. This resultant, partially edited mRNA can then undergo accurate, gRNA-directed cleavage at editing site 2, again precisely as predicted by the enzymatic editing model. All of these enzymatic activities cofractionate with the U-deletion activity and may reside in a single complex. The data imply that each round of editing is a four-step process, involving (i) gRNA-directed cleavage of the pre-mRNA at the bond immediately 5' of the region base paired to the gRNA, (ii) U deletion from or U addition to the 3' OH of the upstream mRNA half, (iii) ligation of the mRNA halves, and (iv) formation of additional base pairing between the correctly edited site and the gRNA that directs subsequent nuclease cleavage at the next editing site.
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Background: Studies suggest that expert performance in sport is the result of long-term engagement in a highly specialized form of training termed deliberate practice. The relationship between accumulated deliberate practice and performance predicts that those who begin deliberate practice at a young age accumulate more practice hours over time and would, therefore, have a significant performance advantage. However, qualitative studies have shown that a large amount of sport-specific practice at a young age may lead to negative consequences, such as dropout, and is not necessarily the only path to expert performance in sport. Studies have yet to investigate the activity context, such as the amount of early sport participation, deliberate play and deliberate practice within which dropout occurs. Purpose: To determine whether the nature and amount of childhood-organized sport, deliberate play and deliberate practice participation influence athletes' subsequent decisions to drop out or invest in organized sport. It was hypothesized that young athletes who drop out will have sampled fewer sports, spent less time in deliberate play activities and spent more time in deliberate practice activities during childhood sport involvement. Participants: The parents of eight current, high-level, male, minor ice hockey players formed an active group. The parents of four high-level, male, minor ice hockey players who had recently withdrawn from competitive hockey formed a dropout group. Data collection: Parents completed a structured retrospective survey designed to assess their sons' involvement in organized sport, deliberate play and deliberate practice activities from ages 6 to 13. Data analysis: A complete data-set was available for ages 6 through 13, resulting in a longitudinal data-set spanning eight years. This eight-year range was divided into three levels of development corresponding to the players' progress through the youth ice hockey system. Level one encompassed ages 6–9, level two included ages 10–11 and level three covered ages 12–13. Descriptive statistics were used to report the ages at which the active and dropout players first engaged in select hockey activities. ANOVA with repeated measures across the three levels of development was used to compare the number of sports the active and dropout players were involved in outside of hockey, the number of hours spent in these sports, and involvement in various hockey-related activities. Findings: Results indicated that both the active and dropout players enjoyed a diverse and playful introduction to sport. Furthermore, the active and dropout players invested similar amounts of time in organized hockey games, organized hockey practices, specialized hockey training activities (e.g. hockey camps) and hockey play. However, analysis revealed that the dropout players began off-ice training at a younger age and invested significantly more hours/year in off-ice training at ages 12–13, indicating that engaging in off-ice training activities at a younger age may have negative implications for long-term ice hockey participation. Conclusion: These results are consistent with previous research that has found that early diversification does not hinder sport-specific skill development and it may, in fact, be preferable to early specialization. The active and dropout players differed in one important aspect of deliberate practice: off-ice training activities. The dropout players began off-ice training at a younger age, and participated in more off-ice training at ages 12 and 13 than their active counterparts. This indicates a form of early specialization and supports the postulate that early involvement in practice activities that are not enjoyable may ultimately undermine the intrinsic motivation to continue in sport. Youth sport programs should not focus on developing athletic fitness through intense and routine training, but rather on sport-specific practice, games and play activities that foster fun and enjoyment.
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Virtual learning environments (VLEs) have witnessed a high evolution, namely regarding their potentialities, the tools and the activities they provide. VLEs enable us to access large quantities of data resulting from both students and teachers’ activities developed in those environments. Monitoring undergraduates’ activities in VLEs is important as it allows us to showcase, in a structured way, a number of indicators which may be taken into account to understand the learning process more deeply and to propose improvements in the teaching and learning strategies as well as in the institution’s virtual environment. Although VLEs provide several data sectorial statistics, they do not provide knowledge regarding the institution’s evolution. Therefore, we consider the analysis of the activity logs in VLEs over a period of five years to be paramount. This paper focuses on the analysis of the activities developed by students in a virtual learning environment, from a sample of undergraduate students, approximately 7000 per year, over a period of five academic years, namely from 2009/2010 to 2013/2014. The main aims of this research work are to assess the evolution of activity logs in the virtual learning environment of a Portuguese public higher education institution, in order to fill possible gaps and to hold out the prospect of new forms of use of the environment. The results obtained from the data analysis show that overall, the number of accesses to the virtual learning environment increased over the five years under study. The most used tools were Resources, Messages and Assignments. The most frequent activities developed with these tools were respectively consulting information, sending messages and submitting assignments. The frequency of accesses to the virtual learning environment was characterized according to the number of accesses in the activity log. The data distribution was divided into five frequency categories named very low, low, moderate, high and very high, determined by the percentiles 20, 40, 60, 80 and 100, respectively. The study of activity logs of virtual learning environments is important not only because they provide real knowledge of the use that undergraduates make of these environments, but also because of the possibilities they create regarding the identification of a need for new pedagogical approaches or a reinforcement of previously consolidated approaches.
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Using a multi-perspective vignette design, we explored predictors of young peoples' (N = 119) propensity to engage in unfaithful activities while dating. Demographic measures, a datding investment model, and measures of functional and dysfunctional impulsivity were used to predict inclination to engage in each of two extradyadic activities (kissing and sexual activity). The results of moderated multiple regression analyses revealed that a respondent's number of sexual partners, level of dysfunctional impulsivity, satisfaction with current relationship, and quality of relationship alternatives significantly predicted inclination to engage in both of the extradyadic activities. Consistent with previous findings, gender only showed significant predictive value in relation to extradyadic sex inclination. Moreover, the association between sex, love, and marriage interacted with gender in the prediction of both extradyadic activities and interacted with commitment in the prediction of extradyadic sex inclination. Suggestions for future research in this area are offered in light of these new findings.
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O presente estudo buscou a compreensão dos motivos que levam as empresas pesquisadas do setor automobilístico a gerir o conhecimento tácito, mediados pela gestão do conhecimento, na área de gestão de desenvolvimento de produtos. As questões de pesquisa que este estudo objetivou responder foram: Como empresas estudadas utilizam o conhecimento tácito para se tornarem mais eficientes e eficazes nas atividades/ operações? De que forma o conhecimento tácito é percebido na organização por parte dos funcionários e gestores? Para responder a estas perguntas houve a investigação de duas empresas do setor automobilístico, na área de desenvolvimento de produtos. Como base teórica para o desenvolvimento do presente estudo autores como Davenport e Prusak (1998), Nonaka e Takeuchi (1997) e Choo (2006) orientam esta pesquisa. A pesquisa abrange duas empresas do ramo automobilístico na região do ABC Paulista, com equivalência no número de funcionários e porte. Dentre os entrevistados há funcionários e gestores de áreas de gestão de projetos e produtos. A metodologia aplicada ao estudo foi de caráter qualitativo por meio de pesquisa exploratória-descritiva, sendo que o método de coleta de dados se deu a partir de entrevistas semiestruturadas. O estudo investigou quais as práticas usadas para a conversão do conhecimento, fatores facilitadores e fatores dificultadores para a conversão do conhecimento e as principais contribuições da aplicação das práticas e iniciativas voltadas gerir o conhecimento tácito, sob a ótica dos gestores e funcionários. Através do presente estudo pode-se verificar que existe a preocupação com a gestão do conhecimento nas empresas estudadas e que há práticas diversas relativas ao conhecimento tácito e que as formas de disseminação deste conhecimento são distintas. Algumas das práticas são os cursos de especialização, brainstorming e lesson learned e conversas informais. Nos fatores facilitadores há a troca de informação entre os pares, reuniões semanais, equipes multidisciplinares/ multifuncionais. Nos fatores dificultadores há a indicação de questões comportamentais, acúmulo de funções e tempo para partilhar informações.
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O presente estudo buscou a compreensão dos motivos que levam as empresas pesquisadas do setor automobilístico a gerir o conhecimento tácito, mediados pela gestão do conhecimento, na área de gestão de desenvolvimento de produtos. As questões de pesquisa que este estudo objetivou responder foram: Como empresas estudadas utilizam o conhecimento tácito para se tornarem mais eficientes e eficazes nas atividades/ operações? De que forma o conhecimento tácito é percebido na organização por parte dos funcionários e gestores? Para responder a estas perguntas houve a investigação de duas empresas do setor automobilístico, na área de desenvolvimento de produtos. Como base teórica para o desenvolvimento do presente estudo autores como Davenport e Prusak (1998), Nonaka e Takeuchi (1997) e Choo (2006) orientam esta pesquisa. A pesquisa abrange duas empresas do ramo automobilístico na região do ABC Paulista, com equivalência no número de funcionários e porte. Dentre os entrevistados há funcionários e gestores de áreas de gestão de projetos e produtos. A metodologia aplicada ao estudo foi de caráter qualitativo por meio de pesquisa exploratória-descritiva, sendo que o método de coleta de dados se deu a partir de entrevistas semiestruturadas. O estudo investigou quais as práticas usadas para a conversão do conhecimento, fatores facilitadores e fatores dificultadores para a conversão do conhecimento e as principais contribuições da aplicação das práticas e iniciativas voltadas gerir o conhecimento tácito, sob a ótica dos gestores e funcionários. Através do presente estudo pode-se verificar que existe a preocupação com a gestão do conhecimento nas empresas estudadas e que há práticas diversas relativas ao conhecimento tácito e que as formas de disseminação deste conhecimento são distintas. Algumas das práticas são os cursos de especialização, brainstorming e lesson learned e conversas informais. Nos fatores facilitadores há a troca de informação entre os pares, reuniões semanais, equipes multidisciplinares/ multifuncionais. Nos fatores dificultadores há a indicação de questões comportamentais, acúmulo de funções e tempo para partilhar informações.
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In today's market, the global competition has put manufacturing businesses in great pressures to respond rapidly to dynamic variations in demand patterns across products and changing product mixes. To achieve substantial responsiveness, the manufacturing activities associated with production planning and control must be integrated dynamically, efficiently and cost-effectively. This paper presents an iterative agent bidding mechanism, which performs dynamic integration of process planning and production scheduling to generate optimised process plans and schedules in response to dynamic changes in the market and production environment. The iterative bidding procedure is carried out based on currency-like metrics in which all operations (e.g. machining processes) to be performed are assigned with virtual currency values, and resource agents bid for the operations if the costs incurred for performing them are lower than the currency values. The currency values are adjusted iteratively and resource agents re-bid for the operations based on the new set of currency values until the total production cost is minimised. A simulated annealing optimisation technique is employed to optimise the currency values iteratively. The feasibility of the proposed methodology has been validated using a test case and results obtained have proven the method outperforming non-agent-based methods.
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Food service on a cruise ship presents some unique challenges. A review of food service in the cruise industry is presented along with some ideas on the future. The case is made for a change in traditional operations with a move toward greater use of computer-driven management techniques.