4,019 research outputs found

    Efeitos do stress térmico na fotoinativação e reparação do fotossistema II numa alga deficiente do ciclo das xantofilas

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    Photosynthesis and primary productivity are very temperature-dependent. Extremely high or low temperatures affect the enzymatic mechanisms of photoprotection (xanthophyll cycle) and exacerbate the photo-imaging effects of high light on photosystem II (PSII). A recently proposed hypothesis states that abiotic stress, including mild cold and heat, enhances photoinhibition of photosynthesis not by directly damaging the PSII, but by inhibiting repair mechanisms. This work intends to test this hypothesis in an as yet unexplored group of green algae (Bryopsidales) without a xanthophyll functional cycle. In order to test this hypothesis, we used the measurement of chlorophyll fluorescence, under light and thermal stress, and subsequent quantification of D1 protein, using the Western blot technique. Our findings showed that for this group of algae, the aforementioned hypothesis is not applicable, as the abiotic stresses affected not only repair mechanisms but also exacerbated photoinhibition. Consequently, the group of green algae (Bryopsidales) showed great potential for future studies in the scope of the investigation regarding repair mechanisms of photosystem II.A fotoss√≠ntese e a produtividade prim√°ria dependem profundamente da temperatura. Temperaturas extremamente altas ou baixas afetam os mecanismos enzim√°ticos de fotoprote√ß√£o (ciclo das xantofilas) e exacerbam os danos provocados pela irradia√ß√£o elevada no fotossistema II (PSII). Uma hip√≥tese recentemente proposta afirma que o stress abi√≥tico, incluindo frio e calor moderado, aumenta a fotoinibi√ß√£o da fotoss√≠ntese n√£o por efeitos diretos no PSII, mas sim pela inibi√ß√£o dos mecanismos de repara√ß√£o. Este trabalho pretende testar essa hip√≥tese num grupo ainda inexplorado de algas verdes (Bryopsidales) que n√£o possuem um ciclo das xantofilas funcional. Para testar esta hip√≥tese, recorremos a medi√ß√Ķes da fluoresc√™ncia da clorofila a, sob stress luminoso e t√©rmico, e posterior quantifica√ß√£o da prote√≠na D1, atrav√©s da t√©cnica do Western blot. Os nossos resultados mostraram que, para este grupo de algas, a hip√≥tese acima mencionada, n√£o √© aplic√°vel, pois os stresses abi√≥ticos afetaram n√£o apenas os mecanismos de reparo, mas tamb√©m exacerbaram a fotoinibi√ß√£o. Consequentemente, o grupo de algas verdes (Bryopsidales) apresentou um grande potencial para futuros estudos no √Ęmbito da investiga√ß√£o dos mecanismos de repara√ß√£o do fotossistema II.Mestrado em Biologia Aplicad

    Fontes de informação como determinantes da capacidade inovadora de empresas de gestão de resíduos : estudo de casos

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    Este trabalho, baseado no estudo de seis empresas do sector de gest√£o de res√≠duos, pretendeu determinar onde e como estas empresas adquirem o conhecimento necess√°rio para o desenvolvimento das suas actividades de inova√ß√£o, o que implicou responder √†s seguintes quest√Ķes de investiga√ß√£o: Quais s√£o os parceiros com que as empresas se relacionam? Qual o papel diferenciado de cada um desses parceiros? Deste modo, tomou-se como quadro conceptual as abordagens actuais sobre a tem√°tica da inova√ß√£o, desenvolvendo-se um suporte te√≥rico e emp√≠rico, que permitiu identificar e analisar os factores externos que influenciam o comportamento inovador destas empresas. Permitiu, verificar que o padr√£o de relacionamentos destas empresas do sector de gest√£o de res√≠duos envolve outras empresas, nomeadamente clientes, fornecedores e concorrentes, bem como institui√ß√Ķes acad√©micas e centros de investiga√ß√£o, e consultores e institui√ß√Ķes de investiga√ß√£o privadas. Tamb√©m permitiu constatar que s√£o mais consistentes as liga√ß√Ķes que estas empresas mant√©m com outras empresas, sejam estas clientes ou fornecedores, do que com institui√ß√Ķes acad√©micas e centros de investiga√ß√£o, e consultores e institui√ß√Ķes de investiga√ß√£o privadas. E, confirmou, que apesar das liga√ß√Ķes serem pontuais, as empresas mais inovadoras, isto √©, as que desenvolvem inova√ß√Ķes do tipo ‚Äúnovo para o mercado‚ÄĚ s√£o as que mais se relacionam com institui√ß√Ķes acad√©micas

    The relevance of external sources of information on the innovative performance of waste management firms : case studies

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    Este trabalho, baseado no estudo de seis empresas do sector de gest√£o de res√≠duos, pretendeu determinar onde e como estas empresas adquirem o conhecimento necess√°rio para o desenvolvimento das suas actividades de inova√ß√£o, o que implicou responder √†s seguintes quest√Ķes de investiga√ß√£o: Quais s√£o os parceiros com que as empresas se relacionam? Qual o papel diferenciado de cada um desses parceiros? Deste modo, tomouse como quadro conceptual as abordagens actuais sobre a tem√°tica da inova√ß√£o, desenvolvendo-se um suporte te√≥rico e emp√≠rico, que permitiu identificar e analisar os factores externos que influenciam o comportamento inovador destas empresas. Permitiu, verificar que o padr√£o de relacionamentos destas empresas do sector de gest√£o de res√≠duos envolve outras empresas, nomeadamente clientes, fornecedores e concorrentes, bem como institui√ß√Ķes acad√©micas e centros de investiga√ß√£o, e consultores e institui√ß√Ķes de investiga√ß√£o privadas. Tamb√©m permitiu constatar que s√£o mais consistentes as liga√ß√Ķes que estas empresas mant√©m com outras empresas, sejam estas clientes ou fornecedores, do que com institui√ß√Ķes acad√©micas e centros de investiga√ß√£o, e consultores e institui√ß√Ķes de investiga√ß√£o privadas. E, confirmou, que apesar das liga√ß√Ķes serem pontuais, as empresas mais inovadoras, isto √©, as que desenvolvem inova√ß√Ķes do tipo ‚Äúnovo para o mercado‚ÄĚ s√£o as que mais se relacionam com institui√ß√Ķes acad√©micas.This research work, based on a multiple case-study of six firms in the sector of waste management, sought to determine where and how these firms acquire the necessary knowledge to develop their innovation activities. This aim required answering the following questions: Which are the partners that interact with the firms? What is the unique role of each partner? Thus, as a conceptual framework the current approaches on the topic of innovation were documented, developing a theoretical and empirical support, which helped identify and analyze the external factors that influence the behavior of these innovative firms. It disclosed that the pattern of relationships of these firms involves other firms, such as customers, suppliers and competitors, as well as academic institutions and research centers, consultants and private research institutions. It also revealed as more consistent the networks developed between these firms and others, being those customers or suppliers, than the established with academic institutions and research centers, and consultants and private research institutions. Furthermore, this study identified the following framework, even though connections may be sporadic, the most innovative firms, i.e. those that develop innovations "new to market", are the most linked to academic institutions

    Propaganda in Disney’s Raya and the Last Dragon: exploring the stereotypes around the ideas of a woman and femininity

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    This thesis sets out to investigate how the ideas of what it means to be a woman and femininity are constructed and propagated through the film Raya and the Last Dragon, the latest Disney Princess film, in the form of stereotypes. Previous studies show that Disney Princess films, from The Walt Disney Company, produce effects on the behaviour and thoughts of children when it comes to gender roles. As propaganda became associated with totalitarian regimes, studies about media effects rarely coin said effects as caused by propaganda. Therefore, propaganda as a field of analysis lacks a body of literature and a consensual set of analysis rules. This thesis contributes to the establishment of propaganda as a field of analysis, by defining it under Jacques Ellul’s categorisation. The study relies on a qualitative analysis based on the propaganda analysis model proposed by Garth Jowett and Victoria O’Donnell. The empirical material consists of the film Raya and the Last Dragon, and it is available on Disney+, the streaming service of The Walt Disney Company. The findings of this thesis illuminate how the ideas of a woman and of femininity are constructed in Raya and the Last Dragon and allow to understand, against the literature review, if these constructions have changed and evolved when compared to previous Disney Princess films. The results indicate that the film presents a world where women and men are seen as equal, leading it to break previous stereotypes associated with women and femininity. By presenting a female-centric story, with independent characters who have diverse personalities and clothing, who fight and have no romantic interests, the film subverts the trope of a passive woman in a dress waiting to be rescued by a man from a powerful evil woman. Additionally, the film rotates around the relationship between Raya and Namaari, using the patriarchal trope of plotting a woman against a woman to focus on female friendship. Yet, as the filmmakers are conditioned by their positionality, some stereotypes are still oriented by patriarchal logic and a western perspective, namely the omnipresence of a patriarchal figure that guides the protagonist. In the end, besides its contributions to the field of propaganda analysis, the thesis updates the tradition of studies done on the gendered stereotypes present in the Disney Princess films

    Novo m√©todo para avalia√ß√£o da sensibilidade cut√Ęnea do p√© diab√©tico: relato preliminar

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    Diabetic neuropathy is an important complication of the disease, responsible for ulceration and amputation of the foot. Prevention of these problems is difficult mainly because there is no method to correctly access sensibility on the skin of the foot. The introduction of the Pressure-Specified Sensory Device (PSSD TM) in the last decade made possible the measurement of pressure thresholds sensed by the patient, such as touch, both static and in movement, on a continuous scale. This paper is the first in Brazil to report the use of this device to measure cutaneous sensibility in 3 areas of the foot: the hallux pulp, the calcaneus, and the dorsum, which are territories of the tibial and fibular nerves. METHOD: Non-diabetic patients were measured as controls, and 2 groups of diabetic patients - with and without ulcers - were compared. The PSSD TM was used to test the 3 areas described above. The following were evaluated: 1 PS (1-point static), 1 PD (1-point dynamic), 2 PS (2-points static), 2 PD (2-points dynamic). RESULTS: The diabetic group had poorer sensibility compared to controls and diabetics with ulcers had poorer sensibility when compared to diabetics without ulcers. The differences were statistically significant (PA neuropatia diab√©tica √© uma complica√ß√£o importante do Diabetes melitus, respons√°vel por ulcera√ß√Ķes e amputa√ß√Ķes de membros inferiores. A preven√ß√£o desses problemas √© dif√≠cil principalmente pela aus√™ncia de m√©todos que avaliem de forma precisa a sensibilidade cut√Ęnea dos p√©s. A introdu√ß√£o do PSSD TM (Pressure-Specified Sensory Device) na d√©cada passada tornou poss√≠vel a medi√ß√£o dos limiares cut√Ęneos de press√£o. Estes s√£o sentidos como est√≠mulos t√°teis tanto est√°ticos como din√Ęmicos. Este artigo √© o primeiro no Brasil a relatar o uso do PSSD TM para avaliar 3 √°reas dos p√©s: polpa do hallux, calc√Ęneo e dorso do p√©, territ√≥rios de inerva√ß√£o dos nervos tibial e fibular. M√ČTODO: Pacientes n√£o diab√©ticos foram utilizados como grupo controle e dois grupos de pacientes diab√©ticos - sem √ļlcera e com √ļlcera - foram analisados. O PSSD TM foi utilizado em 3 modalidades: 1 PS (1 Ponto Est√°tico), 1 PD (1 Ponto din√Ęmico), 2 PS (2 pontos est√°ticos), 2 PD (2 Pontos Din√Ęmicos). Foram avaliadas as 3 √°reas citadas acima. RESULTADOS: Foi observada pior sensibilidade em pacientes diab√©ticos, especialmente no grupo de pacientes com √ļlceras de membros inferiores. As diferen√ßas foram estatisticamente significantes (

    Influencia de la autoliberación miofascial versus estiramientos estáticos en un programa de entrenamiento de fuerza en miembros inferiores.

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    El uso de diferentes estrategias en el calentamiento y recuperaci√≥n de los deportistas son habitualmente utilizadas en la pr√°ctica regular de cualquier actividad f√≠sico-deportiva, ya sea en un simple entrenamiento o en una prueba de competici√≥n, teniendo como fin principal el conseguir las mejores adaptaciones o resultados en cada una de ellas. Hay numerosos estudios que pretenden averiguar las combinaciones m√°s adecuadas para lograr dichos cambios f√≠sicos entre el reposo inicial de un individuo y el trabajo f√≠sico principal que pretende desarrollar, as√≠ como desde esta situaci√≥n de trabajo f√≠sico a la de reposo final, siendo la activaci√≥n inicial y la recuperaci√≥n posterior a trav√©s de unas determinadas aplicaciones t√©cnicas para que interfiera positivamente en el desarrollo √≥ptimo de la capacidad f√≠sica objeto a desarrollar. En estos a√Īos m√°s recientes se ha empezado a utilizar la conocida liberaci√≥n miofascial como t√©cnica de aplicaci√≥n en los calentamientos para la realizaci√≥n de cualquier actividad f√≠sico-deportiva, as√≠ como en la recuperaci√≥n de los deportistas al finalizar dicha actividad. Concretamente la autoliberaci√≥n miofascial a trav√©s del uso del accesorio ‚ÄúFoam Roller‚ÄĚ, es el que despierta gran inter√©s en determinados grupos de investigadores, sobre todo por su incipiente conocimiento y comercializaci√≥n y sus escasas publicaciones al respecto. En este estudio se pretende comprobar la repercusi√≥n que tiene la aplicaci√≥n de los estiramientos est√°ticos pasivos mantenidos y la autoliberaci√≥n miofascial a trav√©s del accesorio ‚ÄúFoam Roller‚ÄĚ tanto antes como despu√©s de un entrenamiento para desarrollar la fuerza muscular en las extremidades inferiores, siendo aplicado a diferentes grupos de poblaci√≥n para su comparaci√≥n. Para ello hemos sometido a 41 sujetos, hombres y mujeres de entre 18 y 35 a√Īos, a un programa de entrenamiento de fuerza de 5 semanas de duraci√≥n y 2 sesiones semanales. Hemos separado a los sujetos en 3 grupos, 15 sujetos en el Grupo Control (solo sesiones de entrenamiento de fuerza), 13 en el Grupo Autoliberaci√≥n Miofascial a trav√©s del accesorio ‚ÄúFoam Roller‚ÄĚ (antes y despu√©s de cada sesi√≥n de entrenamiento de fuerza) y 13 sujetos en el Grupo Estiramientos Est√°ticos (antes y despu√©s de cada sesi√≥n de entrenamiento de fuerza). Todos los sujetos han realizado la misma estructura de entrenamiento (6 series de 6RM en los ejercicios de Extensi√≥n de Rodillas, Flexi√≥n de Rodillas y Flexi√≥n Plantar de tobillos). Se han medido los valores para la Fuerza a trav√©s de ‚ÄúBiodex‚ÄĚ (flexo-extensi√≥n de rodillas y flexo-extensi√≥n de tobillos) y en la plataforma de saltos a trav√©s de ‚ÄúChrono Jump‚ÄĚ (Squat Jump). Adem√°s, con el fin de averiguar la interferencia del programa de entrenamiento de fuerza en los niveles de flexibilidad, se midieron los valores de rango o amplitud de movimiento a trav√©s de ‚ÄúSit and Reach‚ÄĚ (para la flexi√≥n de cadera) y a trav√©s del ‚ÄúLeg Motion‚ÄĚ (instrumento validado para medir la dorsiflexi√≥n de tobillo). Todas las mediciones se realizaron antes y despu√©s de las 5 semanas de intervenci√≥n.The use of different strategies in warm up and recovery of athletes are commonly used in the regular practice of any exercise regularly, either in a single workout or a test competition, the main purpose being the very best adaptations or results in each. Numerous studies aim to find out the most suitable combinations to achieve these physical changes between the initial rest of an individual and the main physical work that aims to develop, as well as from physical work situation to the final resting, with the initial activation and the subsequent recovery through certain technical applications to interfere positively in the optimal development of physical ability to develop object. In these more recent years it has begun to use the technique known as myofascial release application in warm-ups for the realization of any physical and sporting activities, as well as the recovery of athletes at the end of the activity. Specifically self myofascial release through the use of accessory "Foam Roller", which is of great interest to certain groups of researchers, especially in its incipient knowledge and marketing and rare publications. In this study it is to check the impact of the application of those held static stretching liabilities and self myofascial release through the fitting "Foam Roller" both before and and after a workout to build muscle strength in the lower extremities, being applied to different populations for comparison. So we have undergone 41 subjects, men and women between 18 and 35 years, a strength training program of 5 weeks and 2 weekly sessions. We have separated the subjects into 3 groups, 15 subjects in the control group (only sessions of strength training), 13 in the Self Myofascial Release group through the fitting "Foam Roller" (before and after each session of strength training) and 13 subjects in Static Stretching group (before and after each strength training session). All subjects have made the same training structure (6 sets of 6RM exercises in knee extension, knee bend and ankle plantar flexion). They have been measured values for the Force through "Biodex" (flexion and extension of knee and ankle flexion and extension) and platform jumping through "Chrono Jump" (Squat Jump). Furthermore, in order to find the interference of the program of strength training levels of flexibility, range values or range of motion were measured through "Sit and Reach" (for hip flexion) and through "Leg Motion"(validated instrument for measuring ankle dorsiflexion). All measurements were performed before and after 5 weeks of intervention

    Localização e navegação de um veículo de condução autónoma

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    Mestrado em Engenharia Electr√≥nica e Telecomunica√ß√ĶesA √°rea da condu√ß√£o aut√≥noma tem sido palco de grandes desenvolvimentos nos √ļltimos anos. N√£o s√≥ se tem visto um grande impulso na investiga√ß√£o, existindo j√° um n√ļmero consider√°vel de carros aut√≥nomos, mas tamb√©m no mercado, com v√°rios sistemas de condu√ß√£o assistida a equipar ve√≠culos comercializados. No trabalho realizado no √Ęmbito desta disserta√ß√£o, foram abordados e implementados v√°rios t√≥picos relevantes para condu√ß√£o aut√≥noma. Nomeadamente, foram implementados sistemas de mapeamento, localiza√ß√£o e navega√ß√£o num ve√≠culo aut√≥nomo dotado de um sistema de locomo√ß√£o Ackerman. O ve√≠culo √© capaz de construir o mapa da pista e de usar esse mapa para navegar. O mecanismo de mapeamento √© supervisionado, no sentido em que o ve√≠culo tem de ser remotamente controlado de modo a cobrir a totalidade da pista. A localiza√ß√£o do ve√≠culo na pista √© realizado usando um filtro de part√≠culas, usando um modelo de movimento adequado ao seu tipo de locomo√ß√£o. O planeamento de percurso faz-se a dois n√≠veis. A um n√≠vel mais alto, definem-se pontos de passagem na pista que estabelecem o percurso geral a realizar pelo ve√≠culo. A defini√ß√£o destes pontos est√° diretamente relacionada com a concretiza√ß√£o de tarefas impostas ao ve√≠culo. A um n√≠vel mais baixo, o percurso entre pontos adjacentes anteriores √© detalhado numa sequ√™ncia mais fina de pontos de passagem que tem em considera√ß√£o as limita√ß√Ķes do modelo Ackerman da locomo√ß√£o do ve√≠culo. A navega√ß√£o √© adaptativa, no sentido em que se adequa √† exist√™ncia de obst√°culos, entretanto detetados pelo sistema sensorial do ve√≠culo. O sistema sensorial do ve√≠culo √© essencialmente baseado num dispositivo com vis√£o RGB-D (Kinect) montado num suporte com dois graus de liberdade (pan&tilt). Este sistema √© usado concorrentemente para ver a estrada e os obst√°culos que nela possam existir e para detetar e identificar sinais de tr√Ęnsito que aparecem na pista. A aquisi√ß√£o e processamento dos dados sensoriais e a sua transforma√ß√£o em informa√ß√£o (localiza√ß√£o do ve√≠culo na pista, dete√ß√£o e localiza√ß√£o de obst√°culos, dete√ß√£o e identifica√ß√£o dos sinais de tr√Ęnsito) foi trabalho realizado pelo autor. Um agente de software foi desenvolvido para gerir o acesso concorrente ao dispositivo de vis√£o. O ve√≠culo desenvolvido participou na Competi√ß√£o de Condu√ß√£o Aut√≥noma, do Festival Nacional de Rob√≥tica, edi√ß√£o de 2013, tendo alcan√ßado o primeiro lugar.The autonomous driving field has been a stage of major developments in the last years. Not only has been seen a major push in the research, already existing several self driving cars, but also in the market, with several assisted driving systems equipped in commercialized vehicles. In the work developed in the scope of this dissertation, it were approached and developed several relevant topics to the autonomous driving problem. Namely, it were implemented mapping systems, localization and navigation in an autonomous vehicle with an Ackerman locomotion system. The vehicle is capable of building the map of the track and use that map to navigate. The mapping mechanism is supervised, the vehicle has to be remotely controlled to cover the entire track. The localization of the vehicle in the track is accomplished using a particle filter, using the adequate motion model to its locomotion system. The path planning is performed at two levels. At a higher level, the overall course to be performed by the vehicle is defined by passage points. At a lower level, the path between the aforementioned points is detailed in a thiner sequence of points that take into account the limitations of the Ackerman motion model. The navigation is adaptive since it adapts to the existence of the obstacles detected by the robot‚Äôs sensory system. The vehicle‚Äôs sensory system is essentially based on a device with RGB-D vision system (Kinect) mounted over a structure with two degrees of freedom (pan&tilt). This system is concurrently used to see the track and the obstacles that may exist and to detect and identify traffic signs that appear on the track. The acquisition and processing of the sensory data and its transformation in information (localization of the vehicle in the track, detection and localization of obstacles, detection and identification of traffic signs) was work developed by the author. A software agent was developed to manage the concurrent access to the vision device. The developed vehicle participated in the Autonomous Driving Competition, from the Portuguese Robotics Open, 2013 edition, having achieved the first place
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