935 resultados para built-up litter


Relevância:

80.00% 80.00%

Publicador:

Resumo:

In many studies of the side-chain liquid crystalline polymers (SCLCPs) bearing azobenzene mesogens as pendant groups, obtaining the orientation of azobenzene mesogens at a macroscopic scale as well as its control is important, because it impacts many properties related to the cooperative motion characteristic of liquid crystals and the trans-cis photoisomerization of the azobenzene molecules. Various means can be used to align the mesogens in the polymers, including rubbed surface, mechanical stretching or shearing, and electric or magnetic field. In the case of azobenzene-containing SCLCPs, another method consists in using linearly polarized light (LPL) to induce orientation of azobenzene mesogens perpendicular to the polarization direction of the excitation light, and such photoinduced orientation has been the subject of numerous studies. In the first study realized in this thesis (Chapter 1), we carried out the first systematic investigation on the interplay of the mechanically and optically induced orientation of azobenzene mesogens as well as the effect of thermal annealing in a SCLCP and a diblock copolymer comprising two SCLCPs bearing azobenzene and biphenyl mesogens, respectively. Using a supporting-film approach previously developed by our group, a given polymer film can be first stretched in either the nematic or smectic phase to yield orientation of azobenzene mesogens either parallel or perpendicular to the strain direction, then exposed to unpolarized UV light to erase the mechanically induced orientation upon the trans–cis isomerization, followed by linearly polarized visible light for photoinduced reorientation as a result of the cis–trans backisomerization, and finally heated to different LC phases for thermal annealing. Using infrared dichroism to monitor the change in orientation degree, the results of this study have unveiled complex and different orientational behavior and coupling effects for the homopolymer of poly{6-[4-(4-methoxyphenylazo)phenoxy]hexyl methacrylate} (PAzMA) and the diblock copolymer of PAzMA-block- poly{6-[4-(4-cyanophenyl) phenoxy]hexyl methacrylate} (PAzMA-PBiPh). Most notably for the homopolymer, the stretching-induced orientation exerts no memory effect on the photoinduced reorientation, the direction of which is determined by the polarization of the visible light regardless of the mechanically induced orientation direction in the stretched film. Moreover, subsequent thermal annealing in the nematic phase leads to parallel orientation independently of the initial mechanically or photoinduced orientation direction. By contrast, the diblock copolymer displays a strong orientation memory effect. Regardless of the condition used, either for photoinduced reorientation or thermal annealing in the liquid crystalline phase, only the initial stretching-induced perpendicular orientation of azobenzene mesogens can be recovered. The reported findings provide new insight into the different orientation mechanisms, and help understand the important issue of orientation induction and control in azobenzene-containing SCLCPs. The second study presented in this thesis (Chapter 2) deals with supramolecular side-chain liquid crystalline polymers (S-SCLCPs), in which side-group mesogens are linked to the chain backbone through non-covalent interactions such as hydrogen bonding. Little is known about the mechanically induced orientation of mesogens in S-SCLCPs. In contrast to covalent SCLCPs, free-standing, solution-cast thin films of a S-SCLCP, built up with 4-(4’-heptylphenyl) azophenol (7PAP) H-bonded to poly(4-vinyl pyridine) (P4VP), display excellent stretchability. Taking advantage of this finding, we investigated the stretching-induced orientation and the viscoelastic behavior of this S-SCLCP, and the results revealed major differences between supramolecular and covalent SCLCPs. For covalent SCLCPs, the strong coupling between chain backbone and side-group mesogens means that the two constituents can mutually influence each other; the lack of chain entanglements is a manifestation of this coupling effect, which accounts for the difficulty in obtaining freestanding and mechanically stretchable films. Upon elongation of a covalent SCLCP film cast on a supporting film, the mechanical force acts on the coupled polymer backbone and mesogenic side groups, and the latter orients cooperatively and efficiently (high orientation degree), which, in turn, imposes an anisotropic conformation of the chain backbone (low orientation degree). In the case of the S-SCLCP of P4VP-7PAP, the coupling between the side-group mesogens and the chain backbone is much weakened owing to the dynamic dissociation/association of the H-bonds linking the two constituents. The consequence of this decoupling is readily observable from the viscoelastic behavior. The average molecular weight between entanglements is basically unchanged in both the smectic and isotropic phase, and is similar to non-liquid crystalline samples. As a result, the S-SCLCP can easily form freestanding and stretchable films. Furthermore, the stretching induced orientation behavior of P4VP-7PAP is totally different. Stretching in the smectic phase results in a very low degree of orientation of the side-group mesogens even at a large strain (500%), while the orientation of the main chain backbone develops steadily with increasing the strain, much the same way as amorphous polymers. The results imply that upon stretching, the mechanical force is mostly coupled to the polymer backbone and leads to its orientation, while the main chain orientation exerts little effect on orienting the H-bonded mesogenic side groups. This surprising finding is explained by the likelihood that during stretching in the smectic phase (at relatively higher temperatures) the dynamic dissociation of the H-bonds allow the side-group mesogens to be decoupled from the chain backbone and relax quickly. In the third project (Chapter 3), we investigated the shape memory properties of a S-SCLCP prepared by tethering two azobenzene mesogens, namely, 7PAP and 4-(4'-ethoxyphenyl) azophenol (2OPAP), to P4VP through H-bonding. The results revealed that, despite the dynamic nature of the linking H-bonds, the supramolecular SCLCP behaves similarly to covalent SCLCP by exhibiting a two-stage thermally triggered shape recovery process governed by both the glass transition and the LC-isotropic phase transition. The ability for the supramolecular SCLCP to store part of the strain energy above T[subscript g] in the LC phase enables the triple-shape memory property. Moreover, thanks to the azobenzene mesogens used, which can undergo trans-cis photoisomerization, exposure the supramolecular SCLCP to UV light can also trigger the shape recovery process, thus enabling the remote activation and the spatiotemporal control of the shape memory. By measuring the generated contractile force and its removal upon turning on and off the UV light, respectively, on an elongated film under constant strain, it seems that the optically triggered shape recovery stems from a combination of a photothermal effect and an effect of photoplasticization or of an order-disorder phase transition resulting from the trans-cis photoisomerization of azobenzene mesogens.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This analysis introduces results related to development of teaching experience from two professors of one Federal University who have taken part of one action of continued teacher training. We consider that the interplay among the individual, the language and the world cannot function straightly. It occurs through utterances, defined like real unit discursive communication, and genres of discourse (BAKHTIN, 1979/2011). Along the same line, the relation between the employee and his employment do not occur in a direct manner. This relationship takes place through genres of activity (CLOT, 2008/2010). As well as, a domain of speech genres has given possibility to individual an interaction with several discursive fields, a domain of activity genre allows the professional protruding in difficult situations traced in his employment. We know that the drafting for wield the teaching in the Tertiary Education is recommended by LDBEN (9394/96), which suggests that should be done in postgraduate program. In the mean time, what frequently happens an educational background based in a survey and not in the teaching. Thereby, several times we have observed difficulties in the accomplishment of teaching practice. Considering such aspects, this study seeks to comprehend the manner how the lecturers deal with the difficulties encountered in the classroom and how the years of experience have contributed or not for a domain of activity genre. In this regard, we have propped up in the development approach, introduced by Vigotsky, who asserts that the learning suitably organized results in development (VIGOTSKY, 1984/2007) and still explains the development of individual on the basis of relationship that it has with another, the social (VIGOTSKY, 1996b). For this purpose, were accomplished, by means of a snipped filmed lesson from each teacher, four sessions of self-confrontation (FAÏTA, 1996; CLOT, 2008/2010), two Simple and two Crusade, recorded in a visual format. This material was transcribed in accordance with standards from project NURC-SP (PRETI, 1999). For the analysis, we used three mains theories: of Linguistic, is mobilized the concept of speech genres (BAKHTIN) and all discursive topics (JUBRAN; FÁVERO); from Occupational Psychology, is utilized the activity genres (CLOT); from Psychology Historical-Cultural, is adopted the concept from Zone of Proximal Development and another/social in the development of individual (VIGOTSKY). In compliance with the study achieved, was possible to identify the aspects related to development of teaching experience of Tertiary Education. During the classes and reports of self-confrontation, we identify that both the professors, in the beginning of the career, they got more difficulties to deal with hindrances, and which now, with some years of experience, they get to domain better the difficult situations which they come across. They built up, for example, a greater facility in improvise examples in face of students’ difficulties in the comprehension of concepts. These aspects show that the professors have evolved the higher domain of genre, which allow them getting, in addition to turn the unexpected situation around that spring up in the professional context, as well know how to taking action in similar situation, which they have already run into in another moments. This domain enabled and enables the developing of the lecturers over the course of their professional performance.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

A presente dissertação de mestrado vincula-se ao Programa de Pós-Graduação em Educação – PPGEDU da Universidade Federal do Rio Grande – FURG, estando situada na linha de pesquisa Culturas, linguagens e utopias. O estudo tem como objetivo contribuir para pensar a respeito do lugar que as práticas de escrita reflexiva ocupam no curso de Pedagogia da FURG, propondo-se a investigar quais as possíveis contribuições da escrita reflexiva na constituição de professoras em formação. Em sua realização, a pesquisa contou com a participação de seis egressas do já referido curso, as quais disponibilizaram seus registros reflexivos construídos ao longo da disciplina de Estágio dos Anos Iniciais do Ensino Fundamental acerca das práticas educativas desenvolvidas junto da turma de estágio. A partir de uma abordagem qualitativa, a análise dos dados seguiu a orientação da Análise Textual Discursiva (ATD) de Moraes e Galiazzi, a qual consiste na impregnação do material coletado, unitarização, construção de categorias analíticas e por fim a construção de metatextos. As problematizações feitas ao longo da dissertação, encaminharam para pensar que a escrita reflexiva pensada a partir de Marques contribui na constituição das professoras em formação, oferecendo ferramentas para pensar e qualificar a própria prática. Tais ferramentas dizem respeito à possibilidade que as professoras em formação encontram de ampliar a compreensão do vivido como sugerido por Ostetto e de se apropriar de seu fazer por meio da reflexão escrita com a contribuição de Waschauer; ao caráter descritivo presente no registro reflexivo, o qual auxilia na qualificação, na avaliação e no planejamento da prática docente, por meio de elementos possibilitados pela descrição de atividades; por fim a escrita reflexiva contribui com a autoria da própria prática e com a construção de um repertório de experiências proposto por Contreras, ambos possibilitados pelo registro dos sentimentos e das percepções das estagiárias em relação ao estágio.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

As paisagens rurais portuguesas construídas e mantidas ao longo dos tempos por sistemas agrícolas tradicionais, estão hoje ameaçadas por motivos tão diversos como o envelhecimento da população, o abandono rural, a intensificação, a homogeneização dos sistemas de produção e a perda de competitividade. Mas apesar destes problemas, estas paisagens agrícolas, suportam ainda várias funções não produtivas, nomeadamente, constituem, um importante suporte de biodiversidade, pelo que a sua manutenção é importante para a conservação destes habitats e espécies. Eventualmente novas formas de gestão destas paisagens devem ser criadas, nomeadamente com base na combinação de várias funções numa perspectiva de multifuncionalidade, através de uma adaptação e integração de políticas públicas. Estando actualmente em discussão o novo programa de Desenvolvimento Rural e a definição das futuras Medidas Agro-Ambientais, e a gestão e o financiamento da Rede Natura 2000, estamos portanto num momento crítico para decisões futuras, que terão forçosamente que interligar, a agricultura, o ambiente e desenvolvimento das zonas rurais portuguesas. Com o intuito de melhor compreender estas problemáticas, em particular, as transformações em curso na paisagem rural, o papel das Medidas Agro-Ambientais e apresentar possíveis soluções, foi efectuado este estudo de caso no concelho de Marvão, concelho típico das áreas marginais agrícolas do interior sul de Portugal. ABSTRACT; The Portuguese rural landscapes built up and kept throughout the times by traditional agricultural systems, are today threatened by so diverse reasons as the ageing of the population, the agricultural abandonment, the intensification, the homogenization of the production systems and the loss of competitiveness. But despite these problems. These agricultural landscapes still support a multitude of non-commodity functions, and particularly they still constitute an important support of biodiversity and thus their maintenance is important for the conservation of these habitats and species. Probably new management forms must be created based on the combination of various functions and the adaptation and integration of public policies. Being currently in discussion the new program of Rural Development and the definition of the future Agri-Environmental Measures, and the management and the financing of the Natura 2000 Network, we are therefore at a critical moment for future decisions that will forcibly have to establish connections, between the agriculture, the environment and the development of the portuguese agricultural areas. With the intention of better understanding these problems and questions, , the transformations taking place in Portuguese peripheric rural areas, and in particular role of the Agri-Environmental Measures, and also for presenting possible solutions, a case study was analyzed in municipality of Marvão, characteristic of the agricultural marginal areas of the interior Southern Portugal.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Este trabalho tem como finalidade a elaboração de um projeto na área ambiental denominado Manual de Boas Práticas Ambientais para a Indústria do Mobiliário de Madeira. Para conseguir atingir o objetivo proposto, inicialmente foi efetuado um breve enquadramento ao subsetor do mobiliário de madeira a nível nacional, recorrendo à bibliografia disponível apoiada em dados estatísticos de suporte. Foram caracterizados os dois concelhos alvo de estudo, Paços de Ferreira e Paredes por apresentarem a maior concentração industrial no subsetor a nível nacional. Procedeu-se à descrição do processo produtivo da indústria do mobiliário de madeira com a identificação dos seus principais aspetos ambientais. Posteriormente foi aplicado um questionário para verificar como as empresas do subsetor nos concelhos alvo de estudo tratam as questões ambientais da sua atividade industrial. De forma complementar, realizou-se um caso de estudo na empresa IKEA Industry Portugal, Lda, onde foi elaborado um diagnóstico ambiental detalhado com incidência nas boas práticas ambientais. Finalmente foi elaborado o Manual de Boas Práticas Ambientais para a Indústria do Mobiliário de Madeira.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Pempheris vanicolensis has reported for the first time from Persian Gulf (Kish Island). Various aspects of the biology of P. vanicolensis Cuvier & Valenciennes, a recent Lessepsian (Suez Canal) immigrant into the Mediterranean, are given. Red Sea and Mediterranean populations were compared, and the results indicate that the spawning season is shortened in the Mediterranean, continuing from April to September, as opposed to year-round in the Red Sea. Descriptions of a ripe ovary and post-larva from the Mediterranean are given. Individuals reach a mean size of 10.8 cm in their first year, and 14.4 cm in the second year. Little change has occurred in the diet of the immigrant population, and both populations feed nocturnally, chiefly on larval and adult stages of planktonic crustaceans. Direct underwater observations on the diurnal behavior of the species show that the fish leave their daytime cave shelter at sunset, congregate at a nearby site and then migrate inshore and disperse into small groups to feed. Before dawn, they reassemble at the cave's entrance, and finally enter it at sunrise, after the school has built up. Observations on Persian Gulf sweepers show that the fish are segregated into size groups, ranging 15–18 cm adults at depths of 3 m.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

During the late Miocene, exchange between the Mediterranean Sea and Atlantic Ocean changed dramatically, culminating in the Messinian Salinity Crisis (MSC). Understanding Mediterranean-Atlantic exchange at that time could answer the enigmatic question of how so much salt built up within the Mediterranean, while furthering the development of a framework for future studies attempting to understand how changes may have impacted global thermohaline circulation. Due to their association with specific water masses at different scales, radiogenic Sr, Pb, and Nd isotope records were generated from various archives contained within marine deposits to endeavour to understand better late Miocene Mediterranean-Atlantic exchange. The archives used include foraminiferal calcite (Sr), fish teeth and bone (Nd), dispersed authigenic ferromanganese oxyhydroxides (Nd, Pb), and a ferromanganese crust (Pb). The primary focus is on sediments preserved at one end of the Betic corridor, a gateway that once connected the Mediterranean to the Atlantic through southern Spain, although other locations are investigated. The Betic gateway terminated within several marginal sub-basins before entering the Western Mediterranean; one of these is the Sorbas Basin, a well-studied location whose sediments have been astronomically tuned at high temporal resolution, providing the necessary age control for sub-precessional resolution records. Since the climatic history of the Mediterranean is strongly controlled by precessional changes in regional climate, the aim was to produce records at high (sub-precessional) temporal resolution, to be able to observe clearly any precessional cyclicity driven by regional climate which could be superimposed over longer trends. This goal was achieved for all records except the ferromanganese crust record. The 87Sr/86Sr isotope record (Ch. 3) shows precessional frequency excursions away from the global seawater curve. As precessional frequency oscillations are unexpected for this setting, a numerical box model was used to determine the mechanisms causing the excursions. To enable parameterisation of model variables, regional Sr characteristics, data from general circulation model HadCM3L, and new benthic foraminiferal assemblage data are employed. The model results imply that the Sorbas Basin likely had a positive hydrologic budget in the late Miocene, very different to that of today. Moreover, the model indicates that the mechanism controlling the Sr isotope ratio of Sorbas Basin seawater was not restriction, but a lack of density-driven exchange with the Mediterranean. Beyond improving our understanding of how marginal Mediterranean sub-basins may evolve different isotope signatures, these results have implications for astronomical tuning and stratigraphy in the region, findings which are crucial considering the geological and climatic history of the late Miocene Mediterranean is based entirely on marginal deposits. An improved estimate for the Nd isotope signature of late Miocene Mediterranean Outflow (MO) was determined by comparing Nd isotope signatures preserved in the deeper Alborán Sea at ODP Site 978 with literature data as well as the signature preserved in the Sorbas Basin (Ch. 4; -9.34 to -9.92 ± 0.37 εNd(t)). It was also inferred that it is unlikely that Nd isotopes can be used reliably to track changes in circulation within the shallow settings characteristic of the Mediterranean-Atlantic connections; this is significant in light of a recent publication documenting corridor closure using Nd isotopes. Both conclusions will prove useful for future studies attempting to understand changes in Mediterranean-Atlantic exchange. Excursions to high values, with precessional frequency, are also observed in the radiogenic Pb isotope record for the Sorbas Basin (Ch. 5). Widening the scope to include locations further away from the gateways, records were produced for late Miocene sections on Sicily and Northern Italy, and similar precessional frequency cyclicity was observed in the Pb isotope records for these sites as well. Comparing these records to proxies for Saharan dust and available whole rock data indicates that, while further analysis is necessary to draw strong conclusions, enhanced dust production during insolation minima may be driving the observed signal. These records also have implications for astronomical tuning; peaks in Pb isotope records driven by Saharan dust may be easier to connect directly to the insolation cycle, providing improved astronomical tuning points. Finally, a Pb isotope record derived using in-situ laser ablation performed on ferromanganese crust 3514-6 from the Lion Seamount, located west of Gibraltar within the MO plume, has provided evidence that plume depth shifted during the Pliocene. The record also suggests that Pb isotopes may not be a suitable proxy for changes in late Miocene Mediterranean-Atlantic exchange, since the Pb isotope signatures of regional water masses are too similar. To develop this record, the first published instance of laser ablation derived 230Thexcess measurements are combined with 10Be dating.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

This study aimed to understand the relations inside the organizational Structuring of the shrimp Field - the shrimp agribusiness placed in Rio Grande do Norte State and the strategies adopted by its players. In order to achieve that, semi-structured interviews were conducted with samples of various organizations that act in the field, like cooperatives, associations, enterprises of different links in the chain, universities and state agencies. The interviews built up a large collection of secondary data. As expected, it was found that Field and strategies are related in a recursive way: the configuration of the field, a result from his own biography, has decisively influenced the strategies adopted by its actors, who, as evolved, eventually caused further changes in the Field and outlines the plot of this area of interaction. It was found, for example, that after thirty-five years of its genesis, the Field of shrimp RN still has a low level of institutionalization, which helps to understand the difficulty of its actors in establish strategies based on partnerships and cooperation; Those actions are so necessary to alleviate the effects of the crisis that devastated the industry since 2004. It was noticed, however, that this level of institutionalization is a result, beside other factors, the very strategies that field actors are embracing along its trajectory. Thus, this study hopes to have contributed both to the necessary revival of the agency to institutional phenomenon, cited by Oliver (1991), and to meet the need for more contextualized approaches to organizational strategies (MINTZBERG, 1987; CLEGG, 2004; WHITTINGTON, 2004; 2006; SARAIVA and CARRIERI, 2007). It is an exploratory study that needs further investigation in order to get deep in this research. In this sense, others methodologies and theoretical perspectives need to be used, especially those relating to the seizure of the disputes and discursive aspects of power, as salient in the field investigated. Moreover, in terms of "practical actions", it is suggested that, as soon as possible, the main actors of the field (cooperatives, companies, and state entities in class) can be able of agglutinate efforts to support the shrimp field in RN State and make sustainable actions, which can promote the development of activity in a global view. On the apse of shrimp activities everybody wanted to be the "father of the child," Now, someone has to "stay in the goal."

Relevância:

80.00% 80.00%

Publicador:

Resumo:

INTRODUÇÃO: O vírus da dengue é transmitido pela picada do mosquito Aedes aegypti e, o atual programa de controle não atinge o objetivo de impedir sua transmissão. Este trabalho objetivou analisar a relação entre a distribuição espaço-temporal de casos de dengue e os indicadores larvários no município de Tupã, de janeiro de 2004 a dezembro de 2007. MÉTODOS: Foram construídos indicadores larvários por quarteirão e totalidade do município. Utilizou-se o método cross-lagged correlation para avaliar a correlação entre casos de dengue e indicadores larvários. Foi utilizado estimador kernel para análise espacial. RESULTADOS: A correlação cruzada defasada entre casos de dengue e indicadores larvários foi significativa. Os mapas do estimador Kernel da positividade de recipientes indicam uma distribuição heterogênea, ao longo do período estudado. Nos dois anos de transmissão, a epidemia ocorreu em diferentes regiões. CONCLUSÕES: Não ficou evidenciada relação espacial entre infestação larvária e ocorrência de dengue. A incorporação de técnicas de geoprocessamento e análise espacial no programa, desde que utilizados imediatamente após a realização das atividades, podem contribuir com as ações de controle, indicando os aglomerados espaciais de maior incidência.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

No fim da guerra fria, teve início uma nova era para a Bundeswehr. Com a participação em missões no estrangeiro, surgiram novos desafios que influenciaram as diretrizes da defesa, a estrutura da força, a orientação e as necessidades de formação das forças armadas alemãs. Entre 1992 e 2010, foram implementadas alterações profundas para lidar com a nova situação da NATO e da Alemanha na organização. Em 2003, após várias reformas, o ministério da defesa considerou que reformas apenas não eram suficientes, e teve início o chamado processo de transformação. Este processo contínuo influenciou a "face da Bundeswehr mais profundamente do que qualquer outra alteração até à altura. A orientação em missões internacionais era o novo objetivo e uma consequência de experiências na Somália, Bósnia, Kosovo e Afeganistão. Além disso, a crise financeira para as despesas da defesa e a mudança da estrutura da força NATO influenciaram a Bundeswehr de forma semelhante, e impulsionaram a política de defesa alemã também para estas novas direções. A nova Bundeswehr orientada para missões foram moldadas e desenvolvidas de forma diferente, transformação é a nova palavra-chave e este processo contínuo mantém-se até hoje. Abstract: After the end of the cold war a new era began for the Bundeswehr. With the participation in missions out of area, new challenges came up and influenced the defense papers, force structure, orientation and training needs of the German armed forces. Within 1992 and 2010 several far-reaching changes were made, to deal with the new situation of the NATO and Germanys role within the organization. In 2003, after various reforms, reforms only were no longer sufficient in the eyes of acting minister of defense and the so called transformations process was initiated. This continuing process influenced the “face” of the Bundeswehr more deeply than any other changes before. The orientation on out of area missions was the new objective and a consequence from experiences in Somalia, Bosnia, Kosovo and Afghanistan. Beside of that, the financial downturn for defense expenditure and the changing NATO force structure influenced the Bundeswehr in a similar way and pushed the German defense policy into new directions as well. The new mission orientated Bundeswehr was shaped and built up differently, transformation is the new leading word and the ongoing process until today.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

No âmbito do Trabalho de Investigação Aplicada foi elaborada uma caracterização fisiológica do soldado nas operações em áreas edificadas, tendo como objetivo geral contribuir para o quadro teórico e prático na área da motricidade humana, relativamente às aptidões fisiológicas, designadamente: a Frequência Cardíaca, o Consumo de Oxigénio máximo (VO2max) e o Lactato Sanguíneo. Neste estudo foi executada uma pista de combate em áreas edificadas, com o nível de dificuldade crescente, inicialmente sem e com carga (colete balístico) de seguida com o inimigo armado com airsoft e para finalizar, a esquadra de assalto com armas de airsoft. A pista desenrolou-se na Aldeia de Camões em Mafra. Para medição dos parâmetros em estudo, utilizou os monitores cardíacos Garmin Forerunner 310XT, que fornecem os valores das Frequências Cardíacas e o Lactete Plus, que nos dão os valores dos níveis de Lactato Sanguíneo. Verificou-se que não existe uma doutrina de referência que evidencie o treino físico orientado para o combate em áreas edificadas nos dias de hoje. Da análise dos resultados obtidos verificámos que a intensidade do esforço, durante a execução das pistas de combate, foi predominantemente realizada no regime anaeróbio. Com os resultados alcançados durante a realização da pista de combate, identificámos algumas das tarefas mais críticas na sua execução. Apurámos através dos níveis de lactato que a função do comandante de esquadra é de uma intensidade de esforço físico superior a exigida na restante esquadra de assalto.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Este trabalho de investigação aplicada estuda o Combate em Áreas Edificadas aos baixos escalões do Exército Português e do Exército Francês, Tem como principal objetivo identificar as principais diferenças entre os dois Exércitos, através da análise do Combate em Áreas Edificadas, da doutrina, da formação e treino, das capacidades, das vulnerabilidades e potencialidades de ambos neste tipo de combate. Quanto à natureza da investigação, a metodologia usada, foi a investigação aplicada, comparando os dois Exércitos, e utilizando como objetivo de investigação, o objetivo descritivo e explicativo. No que concerne à forma de abordagem, usamos o método dedutivo, descrevendo e explicando o Combate em Áreas Edificadas, as capacidades, a doutrina, a formação e treino, as vulnerabilidades e potencialidades de ambos. Quanto aos procedimentos técnicos usamos o método comparativo segundo a análise SWOT para verificarmos os pontos fortes, pontos fracos, oportunidades e ameaças das capacidades usadas pelos Exércitos. As técnicas de recolha de dados utilizadas, foram, numa primeira fase, a entrevista exploratória a um Oficial Francês com o intuito de receber informações sobre o seu Exército, para iniciarmos a análise documental e analisar os conceitos e numa segunda fase, fizemos entrevistas de confirmação, para analisarmos os meios, o armamento e as vulnerabilidades e potencialidades de ambos os Exército no Combate em Áreas Edificadas. Como principais resultados destacamos as caraterísticas do Combate em Áreas Edificas, na dimensionalidade do campo de batalha, no emprego de forças, na formação e treino, nos meios e armamento. A doutrina portuguesa apresenta como características deste combate a população, o local/terreno e as infraestruturas. A doutrina francesa apresenta estas características como conceito, onde inclui também o impacto meteorológico como característica. No que diz respeito à dimensionalidade do campo de batalha, a doutrina portuguesa define o campo de batalha como multidimensional enquanto a doutrina francesa define-o como tridimensional. Relativamente ao emprego das forças, a principal diferença é que o Exército Francês aborda o conceito armas combinadas, enquanto nós, ainda não o abordamos desta forma. Ao nível da formação e treino, verificamos que as forças operacionais do Exército Francês são sujeitas a uma formação e avaliação periódica no CENZUB, para rever e adotar novas técnicas, enquanto o Exército Português não possui este sistema. No que concerne às capacidades, verificamos que existem diferenças no pessoal e no material, principalmente nos meios, e ao nível do armamento.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Multivariate orthogonal polynomials in D real dimensions are considered from the perspective of the Cholesky factorization of a moment matrix. The approach allows for the construction of corresponding multivariate orthogonal polynomials, associated second kind functions, Jacobi type matrices and associated three term relations and also Christoffel-Darboux formulae. The multivariate orthogonal polynomials, their second kind functions and the corresponding Christoffel-Darboux kernels are shown to be quasi-determinants as well as Schur complements of bordered truncations of the moment matrix; quasi-tau functions are introduced. It is proven that the second kind functions are multivariate Cauchy transforms of the multivariate orthogonal polynomials. Discrete and continuous deformations of the measure lead to Toda type integrable hierarchy, being the corresponding flows described through Lax and Zakharov-Shabat equations; bilinear equations are found. Varying size matrix nonlinear partial difference and differential equations of the 2D Toda lattice type are shown to be solved by matrix coefficients of the multivariate orthogonal polynomials. The discrete flows, which are shown to be connected with a Gauss-Borel factorization of the Jacobi type matrices and its quasi-determinants, lead to expressions for the multivariate orthogonal polynomials and their second kind functions in terms of shifted quasi-tau matrices, which generalize to the multidimensional realm, those that relate the Baker and adjoint Baker functions to ratios of Miwa shifted tau-functions in the 1D scenario. In this context, the multivariate extension of the elementary Darboux transformation is given in terms of quasi-determinants of matrices built up by the evaluation, at a poised set of nodes lying in an appropriate hyperplane in R^D, of the multivariate orthogonal polynomials. The multivariate Christoffel formula for the iteration of m elementary Darboux transformations is given as a quasi-determinant. It is shown, using congruences in the space of semi-infinite matrices, that the discrete and continuous flows are intimately connected and determine nonlinear partial difference-differential equations that involve only one site in the integrable lattice behaving as a Kadomstev-Petviashvili type system. Finally, a brief discussion of measures with a particular linear isometry invariance and some of its consequences for the corresponding multivariate polynomials is given. In particular, it is shown that the Toda times that preserve the invariance condition lay in a secant variety of the Veronese variety of the fixed point set of the linear isometry.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

Dans certains milieux syndicaux québécois, des initiatives porteuses destinées à prévenir les problèmes de santé mentale au travail ont vu le jour. Des représentants syndicaux pionniers ont mis en place des structures d’entraide opérantes, obtenu des jurisprudences importantes et développé des approches innovantes pour corriger ou bonifier l’organisation du travail, et ce depuis plus de trois décennies. Alors que la montée de l’idéologie néolibérale et les principes d’organisation du travail qu’elle sous-tend engendrent une intensification du travail qui fragilise la psyché des travailleurs et que le rapport de force des syndicats s’effrite, il apparaît porteur d’interroger l’expérience de ces représentants syndicaux pour mieux comprendre comment se structure l’action syndicale en santé mentale au travail. Cette thèse fait l’étude de réalisations syndicales québécoises en matière de santé mentale au travail visant à prévenir et à corriger les problèmes de détresse psychologique, d’épuisement professionnel, de harcèlement, de dépression, de violence, de suicides reliés au travail, etc. Pour ce faire, un cadre théorique mixte a été utilisé. D’une part, une perspective large a été adoptée pour comprendre les enjeux entourant les rapports humains au travail et l’action. Pour ce faire, quatre auteurs influents de la philosophie des Lumières et de la philosophie contemporaine ont été sélectionnés, soit Thomas Hobbes, Adam Smith, Karl Marx et Hannah Arendt. Dégager ces différentes perspectives du monde, de l’action et du lien social avait pour objectif de mettre en place une grille d’analyse susceptible de relier l’expérience de représentants syndicaux à ces visions du monde. Il est apparu essentiel de mieux saisir les bases idéologiques sur lesquelles ces derniers ont construit leur action pour comprendre comment elles ont influencé leur démarche singulière et collective. D’autre part, la théorie de l’expérience sociale a été retenue (Dubet, 2009; 1994) pour analyser plus finement le travail des représentant syndicaux. Celle-ci distingue trois logiques d’action complémentaires et en tension avec lesquelles doivent composer les acteurs sociaux : une logique d’intégration, une logique stratégique et logique appuyée sur la subjectivation. La coexistence de ces trois logiques signifie que l’expérience que les individus font du monde n’est pas une simple reproduction de déterminismes qui les précèdent. Les acteurs sont aussi sujets de leur expérience et capables de prendre une distance du social pour comprendre les significations de leur agir; ils s’inscrivent dans le monde dans une dialectique critique. Cette théorie apporte un éclairage permettant de dégager à la fois ce qui freine et ce qui facilite l’action individuelle et collective en matière de santé mentale au travail et de décrire comment des représentants syndicaux se mobilisent pour répondre aux nombreuses attentes des membres. Cette recherche qualitative s’est appuyée sur une méthodologie de récit de vie (Rhéaume 2008; Bertaux 2006). Vingt représentants syndicaux ont témoigné de la souffrance au travail (Dejours, 2008) vécue par leurs membres et ont présenté des actions déployées pour leur venir en aide. Les réalités décrites par les participants montrent comment certains éléments de l’organisation du travail sont associés à des expériences de domination (Martuccelli, 2004): les méfaits du productivisme et de l’hyperflexibilité, les accidents de travail, les maladies professionnelles et les situations d’horreur au travail, les rapports sociaux au travail devenus délétères et les utilisations abusives de l’appareil judiciaire. L’étude démontre aussi à quel point des initiatives portées par des représentants syndicaux contribuent à une résolution de problèmes dans une perspective d’interdépendance, de développement du pouvoir d’agir, de justice sociale et de lutte pour la dignité. Quatre catégories d’initiatives ont été retenues : l’entretien du lien social dans l’entraide au quotidien, la défense juridique et légale des membres, les clauses de convention collective et les actions sur l’organisation du travail. Enfin, la recherche dégage trois profils de représentants syndicaux : la militance qui tente de former un nous, la professionnalisation qui tente de faire reconnaitre son utilité et sa compétence, et l’entraide qui cherche à développer une action engageant le Je. Leur rencontre laisse entrevoir le développement d’une praxis syndicale qui vise à promouvoir et protéger la dignité du travail et des travailleurs.

Relevância:

80.00% 80.00%

Publicador:

Resumo:

The Deccan Volcanic Province (DVP) was built up by three major phases of eruptions; the most voluminous of which, the Deccan Phase 2, encompassed the Cretaceous–Palaeogene (KT) boundary. Deccan eruptions have been implicated as a contributor to the end-Cretaceous mass extinction, however, mechanism by which volcanic activity affected biota remains poorly understood. We applied a combination of rock magnetic techniques scanning electron microscopy to characterize mineral assemblages of three sections of intertrappean lacustrine sediments from the north-western Maharashtra Deccan Volcanic Provinces. Our results indicate that in sediments deposited during the early stages of the Deccan Phase 2, the Daïwal River and Dhapewada sequences, iron-bearing mineral association is dominated by detrital iron oxides (magnetite and hematite) sourced from the weathering of the surrounding basaltic bedrocks, with minor contribution form authigenic iron sulphides (framboidal pyrite, pyrrhotite and/or greigite). The sediments deposited during the final stages of Phase 2 (the Podgawan sequence) differ significantly in their characteristics. In particular, the Podgawan sediments have 1) very low magnetic susceptibility values, but higher terrigenous fraction (clays and shales) content; 2) more complex assemblage of magnetic minerals, 3) ubiquitous presence of Fe–Ca–Ce vanadates; and 4) unusual lithological variations in the middle part of the section (represented by a charcoal-rich level that is capped by a red clay layer containing fossilized bacterial colonies). We suggest that these unusual characteristics reflect increased acidity in the region during the deposition of the Podgawan sequence, likely due to cumulative effects of volcanic aerosols released during the Deccan Phase 2 eruptions. The combination of these features may be used to recognize episodes of increased acidity in the geological record. Our results also contribute to understanding of local vs. global effects of the Deccan volcanism.