923 resultados para meso-scale processes and turbulence


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Sandpit exploitation near Lisbon allowed collecting of many Miocene, non marine fossils. These sands are part of the mostly marine Miocene series in the Lower Tagus basin. The particularly favourable situation led several researchers to deal with marine-continental correlations. Difficulties often concern methodologic aspects. Some poorly based interpretations exerced a lasting influence. A critical approach is presented. Analysis requires data. Methods based upon models often lead to the temptation of fitting data in order to confirm a priori conclusions, or of mixing up data as if of equal statistic value while they have not at all the same weight. Erroneous interpretations' uncritical repetition for many years "upgraded" them into absolute truth. Another point is endemism vs. europeism. Miocene mammals from Lisbon compared well with corresponding French, contemporaneous taxa, while this was apparently not true for Spanish ones. Too much accent had been put on the endemic character of Spanish, or even regional, mammalian faunas. Nationalist bias and sensationalism also weigh, albeit negatively. Meanwhile nearly all the more evident examples as the rhinoceros Hispanotherium are discredited as Iberian endemisms. Taxa may appear as endemic just because they have not yet been found elsewhere. At least for the medium to large-sized mammals, with their huge geographic distribution, faunal differences depend much more on ecology, climate and environmental conditions. Emphasis on differences may also result from researchers that are often in a precarious situation and need very much to achieve short-term, preferably sensational results. Overvalued differences may mask real similarities. Unethic and not scientific behaviour are further enhanced by "nomina nuda" tricks that may simply be a way to circunvent or cheat the Priority Rule. On the other hand, access to communication networks may present as sensational novelties items that are not new at all, misleading the audience. A new class of "science people" arose, created by the media and not by the value of their real achievements. Discussion is presented on sedimentation processes and discontinuities that are often regarded as absolute precision dating tools, as well as on some geochemical and paleomagnetic interpretations. A very good chronologie frame has been obtained for the basin under study on the basis of an impressive set of data, providing a rather detailed and accurate frame for Miocene marine-continental correlations.

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This paper presents the results of an exploratory study on knowledge management in Portuguese organizations. The study was based on a survey sent to one hundred of the main Portuguese organizations, in order to know their current practices relating knowledge management systems (KMS) usage and intellectual capital (IC) measurement. With this study, we attempted to understand what are the main tools used to support KM processes and activities in the organizations, and what metrics are pointed by organizations to measure their knowledge assets.

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The following contribution considers whether global restructuring creates new forms of the division of labor. On the basis of empirical data from a comparative project in 14 European countries, the author supports the hypothesis that in addition to the ongoing process of the internationalization of work, there are ‘hidden’ effects at the local level. From the perspective of three occupational clusters, dynamics can be observed which have differing impacts on the occupational groups. Thus, there is a simultaneous process of restructuring and redefining skills, labor processes and the working organization which forms the daily reality of working men and women.

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Dissertação apresentada para obtenção do Grau de Doutor em Ambiente pela Universidade Nova de Lisboa, Faculdade de Ciências e Tecnologia

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O presente estágio foi desenvolvido na Britafiel. Um dos projectos em que a Empresa se encontra envolvida é o STOCO, pretendendo implementar à escala industrial um processo de coloração de pedra granítica natural para fins decorativos. Foi neste projecto que se enquadrou o estágio. O tema do estágio centra-se no processo de coloração de granito tendo como principal foco a implementação de um processo industrial de produção de granito colorido. O projecto STOCO nasce da necessidade de complementar a actividade da empresa com produtos de maior valor acrescentado para valorização da matéria-prima de base, o granito. STOCO, resultante de Stone Color, é o nome dado ao projecto e ao novo produto que é granito colorido, sob a forma de brita. Pretende-se obter um produto amigo do ambiente e com boas características: manter a textura natural da pedra granítica e assegurar uma boa resistência a factores agressivos. Estudos prévios de qualidade e de toxicidade mostraram que o produto STOCO desenvolvido até então apresenta um bom comportamento face a agressões climatéricas e que não compromete a vida das espécies usadas nos testes (peixes). Em relação aos lixiviados e resíduos da pedra colorida STOCO, estes não apresentaram qualquer problema ambiental, sendo considerado um produto amigo do ambiente. À data de início do presente trabalho estava em funcionamento um equipamento protótipo de produção de granito colorido (100 kg/partida), sendo a instalação e o arranque da unidade industrial (3 ton/h) concretizados no início de 2014, já no decorrer deste trabalho. Os objectivos cumpridos no âmbito deste trabalho foram então a implementação de uma linha industrial de produção de brita colorida, avaliação técnica do processo e do custo industrial de produção associado às matérias-primas. Neste relatório é descrito o processo inicial adoptado e apresentam-se as alterações efectuadas para melhoria do processo produtivo. Resolveram-se problemas como: definição e instalação de equipamentos complementares para a entrada e a saída da brita no equipamento industrial; pó excessivo na brita; cheiro intenso a gás e elevado ruído; adequação do sistema de pintura; e secagem incompleta da brita. Alguns destes problemas não foram totalmente resolvidos, mas sim minimizados. O equipamento industrial necessita ainda de alterações em diversas áreas, que foram identificadas e para as quais são feitas sugestões de melhoria. Conseguiu-se ainda fazer alguns testes para uma possível substituição de alguns constituintes da tinta. Os componentes que entram na composição base da tinta aquosa, são de modo simplificado: ligante, pigmento, solvente e aditivos. Os constituintes que mais encarecem a tinta, e consequentemente o processo em causa, são o ligante e o pigmento. Os estudos efectuados precisam de ser aprofundados, na tentativa de melhorar o processo minimizando os custos de produção. Formalizaram-se os procedimentos escritos de produção STOCO tanto para o protótipo como para o processo industrial e elaborou-se uma ficha técnica de produto para a brita colorida STOCO.

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Dissertação para obtenção do Grau de Mestre em Genética Molecular e Biomedicina

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Introduction: Cellulite is a complex architectural disorder with multifactorial etiologies that is prevalent in 98% of the women (1). Nowadays several aesthetic treatments are being used: surgical, cosmetic, physical, mechanical, and thermal. (2) Most treatments lack a substantial proof of efficacy. Objective: The purpose of this study was to test and evaluate the efficacy of Ultrasound, Homeopathic Ultrasonophoresis, and Homeopathic Mesotherapy versus control in cellulite in a population of women from ESTSP. Methods: Female volunteers (n=23), Caucasian, aged between 18-31 years, with BMI 19-27 kg/m2 with clinical cellulite gradation on the Cellulite Grading Scale of 1 to 4 were included in a control controlled study. Subjects were assigned in four different groups: Group I (Control, n=6), Group II (Ultrasound, (n=5), Group III (Homeopathic Ultrasonophoresis, n=6), Group IV (Homeopathic Mesotherapy, n=6). Groups II to IV were treated 3 times per week, for a total of 10 sessions. Cellulite gradation was evaluated at the beginning and the end of the trial by means of clinical photography, using a Canon IXUS 65 (6 mega pixels). For homeopathic treatments Dr. Reckeweg® Rekin® 59, 13 and 42 – Dietmed were used. The rating of perceived pain during Homeopathic Mesotherapy was evaluated by a visual analogic scale (VAS). The equipment Sonopuls 692, Enraf-Nonius was used for Ultrasound and Ultrasonophoresis treatments. Results:The higher number of participants with improvement in cellulite graduation occurred in group II (80%), followed group III (50%) and by group IV (33%). The group in which more changes in cellulite gradation occurred was group II, 20% of the individuals improved their score in 2 points. Results were statistically different between Group I and Group II, p=0,015. During the treatments of homeopathic mesotherapy the pain diminished 1 value in VAS scale. Discussion and Conclusion: Although all the three interventions groups were effective in the improvement of cellulite, as expected from previous works described in the literature, (2) only the ultrasound group was statistically different from control. These preliminary results point to the need of a new study using a higher number of participants and the same methodology.

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The Internet plays an important role in higher education institutions where Learning Management Systems (LMS) occupies a main role in the eLearning realm. In this chapter we aim to characterize the Internet and LMS usage patterns and their role in the largest Portuguese Polytechnic Institute. The usage patterns were analyzed in two components: characterization of Internet usage and the role of Internet and LMS in education. Using a quantitative approach, the data analysis describes the differences between gender, age and scientific fields. The carried qualitative analysis allows a better understanding of students’ both motivations, opinions and suggestions of improvement. The outcome of this work is the presentation of the Portuguese students’ profile regarding Internet and LMS usage patterns. We expect that these results can be used to select the most suitable digital pedagogical processes and tools to be adopted regarding the learning process and most adequate LMS’s policies.

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EMC2 finds solutions for dynamic adaptability in open systems. It provides handling of mixed criticality multicore applications in r eal-time conditions, withscalability and utmost flexibility, full-scale deployment and management of integrated tool chains, through the entire lifecycle.

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Experimental and clinical data suggest a role of sex steroids in the pathogenesis of multiple sclerosis (MS). Scant information is available about the potential effect of oral contraceptive (OC) use on the prognosis of the disease. We aimed to evaluate this. The study population consisted of 132 women with relapsing-remitting MS before receiving disease modifying treatment and a mean disease duration 6.2 (SD 5.1) years. Three groups of patients were distinguished according to their OC behavior: [1] never-users, patients who never used OC [2] past-users, patients who stopped OC use before disease onset, and [3] after-users, those who used these drugs after disease onset. Multiple linear and logistic regression models were used to analyze the association between oral contraceptive use and annualized relapse rates, disability accumulation and severity of the disease. After-user patients had lower Expanded Disability Status Scale (EDSS) and Multiple Sclerosis Severity Score (MSSS) values than never users (p<0.001 and p=0.002, respectively) and past users (p=0.010 and p=0.002, respectively). These patients were also more likely to have a benign disease course (MSSS<2.5) than never and past users together (OR: 4.52, 95%CI: 2.13-9.56, p<0.001). This effect remained significant after adjustment for confounders, including smoking and childbirths (OR: 2.97, 95%CI: 1.24, 6.54, p=0.011 and for MSSS β: -1.04; 95% C.I. -1.78, -0.30, p=0.006). These results suggest that OC use in women with relapsing-remitting MS is possible associated with a milder disabling disease course.

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O projeto foi realizado na Toyota (divisão fabril de Ovar), no ano letivo 2014/2015, teve por base um estágio extracurricular que foi realizado para que desta forma tomasse contacto com uma realidade concreta e absoluta no contexto empresarial. O estágio serviu, principalmente, como uma experiência na compreensão do funcionamento de uma indústria de automóveis. Este projeto desenvolve-se no âmbito do 2ºano do Mestrado de Logística e apresenta os contributos desenvolvidos no departamento de logística para a reorganização da mesma para a produção de um novo modelo automóvel. Atualmente, a Toyota, para os modelos de automóveis que produz, recebe os componentes em CKD (Completed Knocked Down) provenientes do Japão em lotes de cinco unidades. Estes lotes são armazenados no armazém, de onde só saem quando for dada ordem para serem produzidos. Cada lote tem várias caixas, que são colocadas à vez numa zona comum de abertura. São retidos os componentes das caixas CKD e colocados nos transportadores próprios dos postos correspondentes (supermercado de linha). Isto significa que sempre que é solicitado uma viatura de um determinado lote, são obrigados a produzir as cinco unidades. Isto significa que as restantes unidades do lote terão que ficar em parque aberto a aguardar venda futura, para além de ter um stock desnecessário, estas unidades ficam vulneráveis e sofrem desgaste, pois estão expostas à intempérie, causando graves problemas de qualidade e respetivos custos associados. Recentemente, foi decidida a produção do modelo Land Cruiser 70 na unidade industrial de Ovar, Portugal, o que obrigou a uma reorganização da produção e processos logísticos para a sua produção. Os objetivos que a empresa pretende com a entrada de um novo projeto Land Cruiser 70, são os seguintes: Alterar o sistema de abastecimento, implementando o abastecimento unitário em toda a fábrica para o novo modelo, garantindo o “one by one production”; Definir o funcionamento do processo logístico desde a chegada dos componentes até ficarem disponíveis no supermercado de linha. Para isso será necessário dimensionar armazém e zona de abertura, definir layouts e quantidade de stocks, bem como definir sistemas de comunicação entre abertura e supermercado; Verificar as peças que vão fazer parte do chassi por posto e contabilizar os dolly´s1 necessários; Fazer o layout de abastecimento da linha do chassi; Calcular o tempo de abertura, de abastecimento e de picking do chassi e de triming. Este projeto tem em conta a política de melhoria contínua de forma a conseguir satisfazer o cliente (ser eficaz) utilizando cada vez menos recursos quer físicos quer humanos (ser eficiente, detetar e eliminar os desperdícios). O presente projeto foi inserido na equipa de melhoria contínua da logística, maioritariamente no chassi. Em termos globais, os objetivos propostos neste estágio foram atingidos com êxito.

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Dissertation presented to obtain the Ph.D degree in Biology

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ABSTRACT: In the late seventies the term “Haematological Stress Syndrome” defined some haematological abnormalities appearing in the course of acute and chronic disorders, such as raised plasma levels of fibrinogen (FNG) and factor VIII, reduced fibrinolytic activity and hyperviscosity. In the early nineties the “Membrane stress syndrome hypothesis” proposed the unification of the concepts of haematological stress syndrome with those of oxidation, inflammation and immune activation to explain the pathogenesis of the antiphospholipid syndrome (APS) Antiphospholipid antibodies, coagulation, fibrinolysis and thrombosis. This chapter investigated the occurrence of the “Haematological Stress Syndrome” and thrombosis in 144 participants positive for aPL detected by clotting and immune tests. Among the clotting assays for the detection of lupus anticoagulant, dilute Russell's viper venom time better correlated with a history of venous thrombosis than activated partial thromboplastin time (p<0.0002 vs p<0.009) and was the only test correlated with a history of arterial thrombosis (p<0.01). By regression analysis, serum levels of IgG anticardiolipin antibodies (aCL) associated with the number of venous occlusions (p<0.001). With regards to FNG and von Willebrand factor (vWF), the former rose by 36% (95% CI; 21%, 53%) and the latter by 50% (95% CI; 29%, 75%) at the first venous occlusion and remained unchanged after subsequent occlusions. At variance FNG rose by 45% (95% CI; 31%, 60%) per arterial occlusion and vWF by 27% (95% CI; 10%, 47%) per arterial occlusion throughout. The coagulation/fibrinolytic balance was cross-sectionally evaluated on 18 thrombotic PAPS patients, 18 subjects with persistence of idiopathic aPL and in healthy controls. Markers of thrombin generation prothrombin fragment 1+2 (F1+2), thrombin-antithrombin complex (TAT) and of fibrin turnover D-Dimer (D-D) were higher in thrombotic (p=0.006)and non-thrombotic subjects (p=0.0001) than in controls as were those of D-D (p<0.0001 and p=0.003 respectively). TAT levels did not differ. Gender analysed data revealed blunted tPA release (hence a negative venous occlusion test) in thrombotic females but neither in thrombotic males (p=0.01) nor in asymptomatic subjects of either sex. Also, in both patient groups females had higher mean PAI than males (p<0.0002) and control females (p<0.02). The activity of factor XIII (FXIIIa) was evaluated was evaluated in 29 patients with PAPS, 14 persistent carriers of aPL without thrombosis, 24 thrombotic patients with inherited thrombophilia, 28 healthy controls and 32 patients with mitral and aortic valve prosthesis as controls for FXIII only. FXIIIa was highest in PAPS (p=0.001), particularly in patients with multiple (n=12) than single occlusion (p=0.02) and in correlation with PAI (p=0.003) and FNG (p=0.005). Moreover FXIIIa was strongly associated with IgG aCL and IgG anti-2GPI (p=0.005 for both) in the PAPS group and to a lesser degree in the aPL group (FXIIIa with IgG aCL, p=0.02, with IgG anti-2GPI, p=0.04). Altogether these results indicate: 1) a differential relationship of aPL, vWF and FNG with venous and arterial thrombosis; 2) heightened thrombin generation, accelerated fibrin turnover and fibrinolysis abnormalities also in asymptomatic carriers of aPLs; 3) enhanced FXIIIa that may contribute to atherothrombosis via increased fibrin/fibrinogen cross-linking. Lipid profile, lipid peroxidation and anti-lipoprotein antibodies in thrombotic primary antiphospholipid syndrome. Given the atherogenic lipid profile of SLE, the same possibility was explored in PAPS by comparing high-density lipoprotein (HDL), low-density lipoprotein (LDL), total cholesterol (CHO), apolipoprotein AI (ApoAI), apolipoprotein B (ApoB), triglycerides (TG), anti-lipoprotein antibodies, beta-2-glycoprotein I complexed to oxidized low-density lipoprotein (oxLDL-2GPI) and C-reactive protein (CRP) in 34 thrombotic PAPS patients compared to 36 thrombotic patients with inherited thrombophilia (IT), to 18 subjects persistently positive for antiphospholipid antibodies (aPL) with no underlying autoimmune or non-autoimmune disorders and to 28 healthy controls. Average concentrations of HDL (p<0.0001), LDL (p<0.0001), CHO (p=0.0002), ApoAI (p=0.002) were lower in PAPS whereas average TRY was higher (p=0.01) than other groups. Moreover PAPS showed higher IgG anti-HDL (p=0.01) and IgG anti-ApoAI (p<0.0001) as well as greater average oxLDL-2GPI (p=0.001) and CRP (p=0.003). Within PAPS, IgG anti-HDL correlated negatively to HDL (p=0.004) and was an independent predictor of oxLDL-2GPI (p=0.009). HDL and ApoAI correlated negatively with CRP (p=0.001 and p=0.007, respectively). IgG anti-HDL may hamper the antioxidant and anti-inflammatory effect of HDL favouring low-grade inflammation and enhanced oxidation in thrombotic PAPS. Indeed plasma 8-epi-prostaglandin F2α (a very specific marker of lipid peroxidation) was significantly higher in 10 patients with PAPS than 10 age and sex matched healthy subjects (p=0.0002) and strongly related to the titre of plasma IgG aCL (r=0.89, p=0.0004). Hence oxidative stress, a major player in atherogenesis, also characterises PAPS. Nitric oxide and nitrative stress in thrombotic primary antiphosholipid syndrome. Oxidative stress goes hand in hand with nitrative stress and to address the latter plasma nitrotyrosine (NT, marker of nitrative stress), nitrite (NO2-) and nitrate (NO3-) were measured in 46 thrombotic PAPS patients, 21 asymptomatic but persistent carriers of antiphospholipid antibodies (PCaPL), 38 patients with inherited thrombophilia (IT), 33 patients with systemic lupus erythematosus (SLE) and 29 healthy controls (CTR). Average crude NT was higher in PAPS and SLE (p=0.01) whereas average plasma NO2- was lower in PAPS and average NO3- highest in SLE (p<0.0001). In PAPS, IgG aCL titer and number of vascular occlusions negatively predicted NO2-, (p=0.03 and p=0.001, respectively) whereas arterial occlusions and smoking positively predicted NO3- (p=0.05 and p=0.005). Moreover CRP (an inflammatory marker) positively predicted NT (p=0.004). Nitric oxide metabolites relates to type and number of vascular occlusions and to aPL titers, whereas nitrative stress relates to low grade marker) positively predicted NT (p=0.004). Nitric oxide metabolites relates to type and number of vascular occlusions and to aPL titers, whereas nitrative stress relates to low grade inflammation and both phenomena may have implications for thrombosis and atherosclerosis in PAPS Inflammation and immune activation in thrombotic primary antiphospholipid syndrome. To investigate inflammation and immune activation in thrombotic PAPS high-sensitivity CRP (hs-CRP), serum amyloid A (SAA), oxLDL-2GPI, CRP bound to oxLDL-2GPI (CRP-oxLDL-2GPI) (as inflammatory markers) neopterin (NPT) and soluble CD14 (sCD14) (as immune activation markers) were measured by ELISA in 41 PAPS patients, in 44 patients with inherited thrombophilia (IT) and 39 controls (CTR). Compared to other groups, PAPS presented with higher plasma concentrations of inflammatory, hs-CRP (p=0.0004), SAA (p<0.01), CRP-oxLDL-2GPI (p=0.0004) and immune activation markers, NPT (p<0.0001) and sCD14 (p=0.007). By regression analysis SAA independently predicted thrombosis number (p=0.003) and NPT independently predicted thrombosis type (arterial, p=0.03) and number (p=0.04). These data confirm that low-grade inflammation and immune activation occur and relate to vascular features of PAPS. Antiphosholipid antibodies, haemostatic variables and atherosclerosis in thrombotic primary antiphospholipid syndrome To evaluate whether IgG aCL titre, haemostatic variables and the lipid profile bore any relationship to the intima media thickness (IMT) of carotid arteries high-resolution sonography was applied to the common carotid (CC), carotid bifurcation (CB) and internal carotid (IC) of 42 aPL subjects, 29 with primary thrombotic antiphospholipid syndrome and 13 with persistence of aPL in the absence of any underlying disorder. The following were measured: plasma FNG, vWF, PAI, homocysteine (HC), CHO, TG, HDL, LDL, platelet numbers and aCL of IgG and IgM isotype. By multiple regression analysis, IgG aCL titre independently predicted IMT at all carotid segments examined (p always <0.005). Plasma FNG and HC independently predicted IMT at the CB (p=0.001 and p<0.0001, respectively) and IC (p=0.03 and p<0.0001, respectively). These data strongly support an atherogenic role for IgG aCL in patients with aPL in addition to traditional risk factors. The atherosclerosis hypothesis was investigated in an age and sex-matched case-double-control study including 49 thrombotic PAPS patients (18 M, 31 F, mean age 37 ± 11), 49 thrombotic patients for IT and 49 healthy subjects. Average IMT was always greater in PAPS than control patients (CC: p=0.004, CB: p=0.013, IC: p=0.001). By dividing participants into age tertiles the IMT was greater in the second (CC: p=0.003, CB: p=0.023, IC: p=0.003) and third tertiles (CC: p=0.03, CB: p=0.004, IC: p=0.007). Conclusion: Coagulation activation, fibrinolysis depression, hightened fibrin turnover, oxidative and nitrative stress in parallel with low grade inflammation and immune activation characterise thrombotic PAPS: all these are early atherogenic processes and contribute to the demonstrated premature atherosclerosis that should be considered a clinical feature of PAPS.