227 resultados para ALV-2283
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2000 Mathematics Subject Classification: Primary 62F35; Secondary 62P99
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In this work we demonstrate the potential of permanent magnet based magnetic resonance sensors to monitor and assess the extent of pore clogging in water filtration systems. The performance of the sensor was tested on artificially clogged gravel substrates and on gravel bed samples from constructed wetlands used to treat wastewater. Data indicate that the spin lattice relaxation time is linearly related to the hydraulic conductivity in such systems. In addition, within biologically active filters we demonstrate the ability to determine the relative ratio of biomass to abiotic solids, a measurement which is not possible using alternative techniques. © 2011 The Royal Society of Chemistry.
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The study of III-nitride materials (InN, GaN and AlN) gained huge research momentum after breakthroughs in the production light emitting diodes (LEDs) and laser diodes (LDs) over the past two decades. Last year, the Nobel Prize in Physics was awarded jointly to Isamu Akasaki, Hiroshi Amano and Shuji Nakamura for inventing a new energy efficient and environmental friendly light source: blue light-emitting diode (LED) from III-nitride semiconductors in the early 1990s. Nowadays, III-nitride materials not only play an increasingly important role in the lighting technology, but also become prospective candidates in other areas, for example, the high frequency (RF) high electron mobility transistor (HEMT) and photovoltaics. These devices require the growth of high quality III-nitride films, which can be prepared using metal organic vapour phase epitaxy (MOVPE). The main aim of my thesis is to study and develop the growth of III-nitride films, including AlN, u-AlGaN, Si-doped AlGaN, and InAlN, serving as sample wafers for fabrication of ultraviolet (UV) LEDs, in order to replace the conventional bulky, expensive and environmentally harmful mercury lamp as new UV light sources. For application to UV LEDs, reducing the threading dislocation density (TDD) in AlN epilayers on sapphire substrates is a key parameter for achieving high-efficiency AlGaNbased UV emitters. In Chapter 4, after careful and systematic optimisation, a working set of conditions, the screw and edge type dislocation density in the AlN were reduced to around 2.2×108 cm-2 and 1.3×109 cm-2 , respectively, using an optimized three-step process, as estimated by TEM. An atomically smooth surface with an RMS roughness of around 0.3 nm achieved over 5×5 µm 2 AFM scale. Furthermore, the motion of the steps in a one dimension model has been proposed to describe surface morphology evolution, especially the step bunching feature found under non-optimal conditions. In Chapter 5, control of alloy composition and the maintenance of compositional uniformity across a growing epilayer surface were demonstrated for the development of u-AlGaN epilayers. Optimized conditions (i.e. a high growth temperature of 1245 °C) produced uniform and smooth film with a low RMS roughness of around 2 nm achieved in 20×20 µm 2 AFM scan. The dopant that is most commonly used to obtain n-type conductivity in AlxGa1-xN is Si. However, the incorporation of Si has been found to increase the strain relaxation and promote unintentional incorporation of other impurities (O and C) during Si-doped AlGaN growth. In Chapter 6, reducing edge-type TDs is observed to be an effective appoach to improve the electric and optical properties of Si-doped AlGaN epilayers. In addition, the maximum electron concentration of 1.3×1019 cm-3 and 6.4×1018 cm-3 were achieved in Si-doped Al0.48Ga0.52N and Al0.6Ga0.4N epilayers as measured using Hall effect. Finally, in Chapter 7, studies on the growth of InAlN/AlGaN multiple quantum well (MQW) structures were performed, and exposing InAlN QW to a higher temperature during the ramp to the growth temperature of AlGaN barrier (around 1100 °C) will suffer a significant indium (In) desorption. To overcome this issue, quasi-two-tempeature (Q2T) technique was applied to protect InAlN QW. After optimization, an intense UV emission from MQWs has been observed in the UV spectral range from 320 to 350 nm measured by room temperature photoluminescence.
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“Governments of the Industrial World, you weary giants of flesh and steel, I come from Cyberspace, the new home of Mind. On behalf of the future, I ask you of the past to leave us alone. You are not welcome among us. You have no sovereignty where we gather (…)” (Barlow 1996). Barlow’s declaration of independence of February 8 1996 was an expression of the libertarian approaches that have run through the Internet since its inception, and is the root of the misapprehension that the internet is somehow unregulated by state sovereignty. But why was it published that day? What happened?
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Currently, there is increasing use of nanomaterials in the food industry thanks to the many advantages offered and make the products that contain them more competitive in the market. Their physicochemical properties often differ from those of bulk materials, which require specialized risk assessment. This should cover the risks to the health of workers and consumers as well as possible environmental risks. The risk assessment methods must go updating due to more widespread use of nanomaterials, especially now that are making their way down to consumer products. Today there is no specific legislation for nanomaterials, but there are several european dispositions and regulations that include them. This review gives an overview of the risk assessment and the existing current legislation regarding the use of nanotechnology in the food industry.
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Pyhäjoen asukasmäärän ennustetaan kasvavan ydinvoimalan rakentamisen myötä. Kasvu näkyy myös taajamassa, missä sekä yleis- että asemakaava mahdollistavat uusien asuinalueiden rakentamisen ja keskusta-alueen tiivistämisen ja laajentamisen. Suunnittelukohteena on Pyhäjoen Vanhatie ja Virastotie, jotka ovat taajaman sisäisen liikenteen tärkeimmät väylät. Suunnittelu tehdään ydinkeskustan alueella seinästä seinään. Suunnittelukohteena on myös valtatien liittymät sekä tori. Suunnittelualueen liikennemäärät ovat vähäisiä, eikä liikenteellisiä ongelmia ennusteta syntyvän, vaikka liikennemäärä kasvaisikin suhteellisesti paljon. Eniten liikennettä on taajaman sivuitse menevällä valtatiellä 8 ja sen liittymissä liikenteen lisäys näkynee onnettomuuksien kasvuna, jos mitään toimenpiteitä ei tehtäisi. Tiet ovat rakenteelltaan kohtuullisessa kunnossa, joskin kuluneita. Ympäristöllisesti suunnittelualue on mielenkiintoinen, sillä Vanhatie on osa Pohjanlahden Rantatietä ja sillä onkin matkailutie-status. Tie on raittimainen, ja sen varrella on useita mielenkiintoisia kohteita, kuten vanhat rakennukset ja puut sekä kalliopaljastumat. Suunnittelujakson eteläpäässä on Etelänkylän Isosilta, joka on Suomen vanhin liikennekäytössä oleva puusilta. Se onkin museosilta. Silta on huonokuntoinen. Tavoitteena on löytää toteuttamiskelpoiset toimenpiteet, joilla ydinkeskusta-alueella tien luonnetta muutetaan keskustamaisemmaksi kaduksi. Torin ja ydinkeskustan yleisilme on tehtävä nykyistä houkuttelevammaksi myös ohikulkevien silmissä. Tavoitteena on saada valtatien kulkijat pistäytymään Pyhäjoella. Kyseiset väylät ovat toistaiseksi maanteitä, mutta tavoitteena on toimenpiteiden toteuttamisen jälkeen muuttaa ne kaduiksi. Toimenpide-esitykset ovat keskittyneet ydinkeskustan alueelle. Vanhatien ja Virastotien liittymäalue sekä kunnantalon edusta rakennetaan torimaiseksi aukioksi. Alue muuttuu yhteistilaksi, jossa jalankulku ja pyöräily on helppoa ja turvallista. Tapahtumia on helppo tarvittaessa laajentaa liikennenalueille. Samoja periaatteita käytetään torin parantamisessa, jossa tori laajenee visuaalisesti Vanhatielle. Suunnittelu on tehty siitä lähtökohdasta, että tori säilyy nykypaikallaan ja mahdollinen Pyhäjoki-talo rakennetaan nykyisen Salen paikalla torin pariksi. Valtatieliittymistä Virastotien liittymän parantaminen on jo suunniteltu aiemmin. Tiiranmaantien liittymä esitetään porrastettavaksi yleiskaavan periaatteen mukaisesti. Vihannintien liittymään rakennetaan turvasaarekket. Merkittävä toimenpide on esitys erityiskohteiden valaisemiseksi. Niitä ovat muun muassa sillat, vanhat isot puut, kalliopaljastumat ja osin myös vanhat rakennuksetkin. Muualla toimenpiteet ovat lähinnä jalankulku- ja pyöräteiden täydentämistä ja viheralueiden kunnostamista. Esitetyt toimenpiteet mahdollistavat kaavojen toteuttamisen. Muutamassa kohdassa asemakaavaa on muutetava toimenpiteiden mahdollistamiseksi. Lähiympäristö paranee, kun katupuita uusitaan ja täydennetään. Rakentamisen kustannukset ovat yhteensä noin 5,2 miljoonaa euroa (alv 0%).
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We present a dynamic distributed load balancing algorithm for parallel, adaptive finite element simulations using preconditioned conjugate gradient solvers based on domain-decomposition. The load balancer is designed to maintain good partition aspect ratios. It calculates a balancing flow using different versions of diffusion and a variant of breadth first search. Elements to be migrated are chosen according to a cost function aiming at the optimization of subdomain shapes. We show how to use information from the second step to guide the first. Experimental results using Bramble's preconditioner and comparisons to existing state-of-the-art balancers show the benefits of the construction.
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El creciente número de sitios y recursos en Internet ha dificultado el proceso de búsqueda y recuperación de información útil para la formación e investigación. Aunque la Red cuenta con importantísimas fuentes, es desconocida por los motores de búsqueda tradicionales, a esta parte se le llama Red Profunda. Para acceder a este pequeño universo de Internet es necesario conocer los mecanismos, estrategias y herramientas que faciliten y garanticen el logro de nuestros objetivos.
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Adoptive immunotherapy and oncolytic virotherapy are two promising strategies for treating primary and metastatic malignant brain tumors. We demonstrate the ability of adoptively transferred tumor-specific T cells to rapidly mediate the clearance of established brain tumors in several mouse models. Similar to the clinical situation, tumor recurrences are frequent and result from immune editing of tumors. T cells can eliminate antigen-expressing tumor cells but are not effective against antigen loss variant (ALV) cancer cells that multiply and repopulate a tumor. We show that the level of tumor antigen present affects the success of adoptive T cell therapy. When high levels of antigen are present, tumor stromal cells such as microglia and macrophages present tumor peptide on their surface. As a result, T cells directly eliminate cancer cells and cross-presenting stromal cells and indirectly eliminate ALV cells. We were able to show the first direct evidence of tumor antigen cross-presentation by CD11b+ stromal cells in the brain using soluble, high-affinity T cell receptor monomers. Strategies that target brain tumor stroma or increase antigen shedding from tumor cells leading to increased crosspresentation by stromal cells may improve the clinical success of T cell adoptive therapies. We evaluated one potential strategy to complement adoptive T cell therapy by characterizing the oncolytic effects of myxoma virus (MYXV) in a syngeneic mouse brain tumor model of metastatic melanoma. MYXV is a rabbit poxvirus with strict species tropism for European rabbits. MYXV can also infect mouse and human cancer cell lines due to signaling defects in innate antiviral mechanisms and hyperphosphorylation of Akt. MYXV kills B16.SIY melanoma cells in vitro, and intratumoral injection of virus leads to robust, selective and transient infection of the tumor. We observed that virus treatment recruits innate immune cells iii to the tumor, induces TNFα and IFNβ production in the brain, and results in limited oncolytic effects in vivo. To overcome this, we evaluated the safety and efficacy of co-administering 2C T cells, MYXV, and neutralizing antibodies against IFNβ. Mice that received the triple combination therapy survived significantly longer with no apparent side effects, but eventually relapsed. Based on these findings, methods to enhance viral replication in the tumor and limit immune clearance of the virus will be pursued. We conclude that myxoma virus should be further explored as a vector for transient delivery of therapeutic genes to a tumor to enhance T cell responses.
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Relatório de estágio apresentado à Escola Superior de Educação de Paula Frassinetti para obtenção de grau de Mestre em Educação Pré-Escolar e Ensino do 1º Ciclo do Ensino Básico
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Size-selective harvest of fish and crustacean populations has reduced stock numbers, and led to reduced growth rates and earlier maturation. In contrast to the focus on size-selective effects of harvest, here, we test the hypothesis that fishing may select on life-history traits (here, growth rate) via behaviour, even in the absence of size selection. If true, then traditional size-limits used to protect segments of a population cannot fully protect fast growers, because at any given size, fast-growers will be more vulnerable owing to bolder behaviour. We repeatedly measured individual behaviour and growth of 86 crayfish and found that fast-growing individuals were consistently bold and voracious over time, and were subsequently more likely to be harvested in single- and group-trapping trials. In addition, there was some indication that sex had independent effects on behaviour and trappability, whereby females tended to be less active, shyer, slower-growing and less likely to be harvested, but not all these effects were significant. This study represents, to our knowledge, the first across-individual support for this hypothesis, and suggests that behaviour is an important mechanism for fishing selectivity that could potentially lead to evolution of reduced intrinsic growth rates.
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Introdução: A elaboração de registos de enfermagem na Sala de Emergência constitui um desafio, havendo necessidade de documentar a avaliação inicial, as intervenções de enfermagem e a evolução do estado do doente. Metodologia: Os principais objectivos deste estudo descritivo foram: construir uma checklist de avaliação primária na Sala de Emergência, a First-Check; validar o seu conteúdo através de um painel Delphi e avaliar, na perspectiva dos enfermeiros, a usabilidade e utilidade da First-Check. Foi assim criada uma checklist de avaliação primária do doente na Sala de Emergência, a First-Check, baseada no ABCDE, como método facilitador dos registos de enfermagem, mas também da avaliação do doente e das próprias intervenções de enfermagem. A amostra foram 20 enfermeiros peritos em urgência e emergência e 35 enfermeiros que exerciam funções num serviço de urgência.Resultados: Inicialmente foi criado um painel de Delphi com um grupo de 20 peritos que num total de duas rondas procedeu à validação dos conteúdos da checklist. Posteriormente foi aplicado um questionário a uma amostra de 35 enfermeiros para estudar o instrumento quanto à sua usabilidade e utilidade. Estes participantes estão descontentes quanto ao modelo de registos de enfermagem actual e confirmam a usabilidade e utilidade da First-Check. Na sua opinião a First-Check vai promover o grau de satisfação dos enfermeiros quanto aos registos na Sala de Emergência, trazendo vantagens em relação ao modelo anterior e facilitando os registos de enfermagem. A First-Check é util para a avaliação primária do doente na Sala de Emergência, para a promoção da continuidade de cuidados, para melhorar a comunicação com a equipa multidisciplinar e para facilitar as intervenções de enfermagem ao doente na Sala de Emergência. Conclusão: A First-Check é válida e útil para a avaliação primária do doente na Sala de Emergência promovendo a qualidade dos cuidados prestados ao doente.