445 resultados para Hodgson, Geoffrey M
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In this paper, we propose the Distributed using Optimal Priority Assignment (DOPA) heuristic that finds a feasible partitioning and priority assignment for distributed applications based on the linear transactional model. DOPA partitions the tasks and messages in the distributed system, and makes use of the Optimal Priority Assignment (OPA) algorithm known as Audsley’s algorithm, to find the priorities for that partition. The experimental results show how the use of the OPA algorithm increases in average the number of schedulable tasks and messages in a distributed system when compared to the use of Deadline Monotonic (DM) usually favoured in other works. Afterwards, we extend these results to the assignment of Parallel/Distributed applications and present a second heuristic named Parallel-DOPA (P-DOPA). In that case, we show how the partitioning process can be simplified by using the Distributed Stretch Transformation (DST), a parallel transaction transformation algorithm introduced in [1].
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23rd International Conference on Real-Time Networks and Systems (RTNS 2015). 4 to 6, Nov, 2015, Main Track. Lille, France. Best Paper Award Nominee
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Presented at SEMINAR "ACTION TEMPS RÉEL:INFRASTRUCTURES ET SERVICES SYSTÉMES". 10, Apr, 2015. Brussels, Belgium.
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Presented at INForum - Simpósio de Informática (INFORUM 2015). 7 to 8, Sep, 2015. Portugal.
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Ligand K-edge XAS of an [Fe3S4]0 model complex is reported. The pre-edge can be resolved into contributions from the í2Ssulfide, í3Ssulfide, and Sthiolate ligands. The average ligand-metal bond covalencies obtained from these pre-edges are further distributed between Fe3+ and Fe2.5+ components using DFT calculations. The bridging ligand covalency in the [Fe2S2]+ subsite of the [Fe3S4]0 cluster is found to be significantly lower than its value in a reduced [Fe2S2] cluster (38% vs 61%, respectively). This lowered bridging ligand covalency reduces the superexchange coupling parameter J relative to its value in a reduced [Fe2S2]+ site (-146 cm-1 vs -360 cm-1, respectively). This decrease in J, along with estimates of the double exchange parameter B and vibronic coupling parameter ì2/k-, leads to an S ) 2 delocalized ground state in the [Fe3S4]0 cluster. The S K-edge XAS of the protein ferredoxin II (Fd II) from the D. gigas active site shows a decrease in covalency compared to the model complex, in the same oxidation state, which correlates with the number of H-bonding interactions to specific sulfur ligands present in the active site. The changes in ligand-metal bond covalencies upon redox compared with DFT calculations indicate that the redox reaction involves a two-electron change (one-electron ionization plus a spin change of a second electron) with significant electronic relaxation. The presence of the redox inactive Fe3+ center is found to decrease the barrier of the redox process in the [Fe3S4] cluster due to its strong antiferromagnetic coupling with the redox active Fe2S2 subsite.
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A História do tratamento cirúrgico do cancro da mama é bem demonstrativa de que a verdade em Medicina é circunstancial, e que o caminho a percorrer no sentido de a alcançar é árduo. Mostra, também, como ao longo dos séculos o empirismo vai dando lugar ao método científico, e como os estudos prospectivos, controlados e randomizados determinam a alteração dos conceitos e a consequente modificação das técnicas cirúrgicas. Estas vão desde os métodos bárbaros, à luz dos conceitos actuais, que, da Grécia antiga se estendem até à descoberta da anestesia – em que se destacam nomes como Henri de Mondeville, Guy de Chaulliac e Lanfranco na Idade Média, von Hilden e Ambroise Paré no Renascimento, ou H.F. Le Dran, J.L. Petit e Benjamim Bell, no tempo do Iluminismo – até às técnicas cada vez mais meticulosas e racionais, já na Idade Contemporânea, sucessivamente devidas a James Paget, Joseph Pancoast, Charles Moore, William Stewart Halsted, William e Richard Handley, Geoffrey Keynes, Robert McWhirter, George Crile Jr., Cushman Haagensen, Dahl-Iversen, Jerome Urban, David Patey, Bernard Fisher e Umberto Veronesi, entre outros que souberam criar novos paradigmas na História do Tratamento Cirúrgico do Cancro da Mama, para se chegar à prática actual de cirurgia conservadora (mamária e axilar)com reconstrução.
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Série II - Nºs 8 e 9 - Colóquios - I Jornada de Cultura Inglesa - Família e Educação
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O outor estuda os processos de combate aos acidentes pelas picadas dos escorpiões, visando: a) Profilaxia e b) Terapêutica. Refere-se à luta nos campos e nas cidades e aqui, dentro e fora dos domicílios. Assinala os diferentes métodos para o combate a êsses artrópodos peçonhentos. Fala na luta direta, indireta, na vacinação pelo anaveneno, na propaganda pela educação racional da população contra o perigo dos acidentes. Refere-se à "cata" dos escorpiões, à luta química, ao emprêgo de animais escorpiófagos, á feitura de casas e jardins anti-escorpiões. Na primeira parte do presente trabalho o autor trata da luta química pelo d. D. T. contra os tityus bahiensis e serrulatus, concluindo que êste corpo químico é um poderoso elemento de luta contra êstes escorpiões. Na segunda parte do trabalho, o autor trata da terapêutica dos acidentes. Mostra a necessidade do emprêgo convenientemente da única terapêutica racional e eficaz contra a intoxicação escorpiônica: a soroterapia específica. Assinala a necessidade da injeção de doses maciças de um sôro de alta valência, preparado em bovídeos, para evitar o mais possível o choque anafilático, no menor tempo possível após as picadas. Aconselha o empêgo de anaveneno escorpiônico, para vacinação principalmente de crianças de baixa idade, nos lugares fortemente infestados pelos escorpiões (principalmente Tityus serrulatus), maximé quando no local não houver sôro anti-escorpiônico específico, como meio preventivo contra a gravidade das intoxicações. Cita finalmente os trabalhos recentes de Grasset, Shaasfsma e Hodgson, na África do Sul, que confirmam muitas idéias do autor e mostram a unidade universal do síndromo escorpiônico descrito no Brasil.
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In this paper we attempt an empirical application of the multi-region input-output (MRIO) method in order to enumerate the pollution content of interregional trade flows between five Mid-West regions/states in the US –Illinois, Indiana, Iowa, Michigan and Wisconsin – and the rest of the US. This allows us to analyse some very important issues in terms of the nature and significance of interregional environmental spillovers within the US Mid-West and the existence of pollution ‘trade balances’ between states. Our results raise questions in terms of the extent to which authorities at State level can control local emissions where they are limited in the way some emissions can be controlled, particularly with respect to changes in demand elsewhere in the Mid-West and US. This implies a need for policy co-ordination between national and state level authorities in the US to meet emissions reductions targets. The existence of an environmental trade balances between states also raises issues in terms of net losses/gains in terms of pollutants as a result of interregional trade within the US and whether, if certain activities can be carried out using less polluting technology in one region relative to others, it is better for the US as a whole if this type of relationship exists.
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To develop a comprehensive overview of copy number aberrations (CNAs) in stage-II/III colorectal cancer (CRC), we characterized 302 tumors from the PETACC-3 clinical trial. Microsatellite-stable (MSS) samples (n = 269) had 66 minimal common CNA regions, with frequent gains on 20 q (72.5%), 7 (41.8%), 8 q (33.1%) and 13 q (51.0%) and losses on 18 (58.6%), 4 q (26%) and 21 q (21.6%). MSS tumors have significantly more CNAs than microsatellite-instable (MSI) tumors: within the MSI tumors a novel deletion of the tumor suppressor WWOX at 16 q23.1 was identified (p<0.01). Focal aberrations identified by the GISTIC method confirmed amplifications of oncogenes including EGFR, ERBB2, CCND1, MET, and MYC, and deletions of tumor suppressors including TP53, APC, and SMAD4, and gene expression was highly concordant with copy number aberration for these genes. Novel amplicons included putative oncogenes such as WNK1 and HNF4A, which also showed high concordance between copy number and expression. Survival analysis associated a specific patient segment featured by chromosome 20 q gains to an improved overall survival, which might be due to higher expression of genes such as EEF1B2 and PTK6. The CNA clustering also grouped tumors characterized by a poor prognosis BRAF-mutant-like signature derived from mRNA data from this cohort. We further revealed non-random correlation between CNAs among unlinked loci, including positive correlation between 20 q gain and 8 q gain, and 20 q gain and chromosome 18 loss, consistent with co-selection of these CNAs. These results reinforce the non-random nature of somatic CNAs in stage-II/III CRC and highlight loci and genes that may play an important role in driving the development and outcome of this disease.
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Gap junction connexin-43 (Cx43) molecules are responsible for electrical impulse conduction in the heart and are affected by transforming growth factor-β (TGF-β). This cytokine increases during Trypanosoma cruzi infection, modulating fibrosis and the parasite cell cycle. We studied Cx43 expression in cardiomyocytes exposed or not to TGF-β T. cruzi, or SB-431542, an inhibitor of TGF-β receptor type I (ALK-5). Cx43 expression was also examined in hearts with dilated cardiopathy from chronic Chagas disease patients, in which TGF-β signalling had been shown previously to be highly activated. We demonstrated that TGF-β treatment induced disorganised gap junctions in non-infected cardiomyocytes, leading to a punctate, diffuse and non-uniform Cx43 staining. A similar pattern was detected in T. cruzi-infected cardiomyocytes concomitant with high TGF-β secretion. Both results were reversed if the cells were incubated with SB-431542. Similar tests were performed using human chronic chagasic patients and we confirmed a down-regulation of Cx43 expression, an altered distribution of plaques in the heart and a significant reduction in the number and length of Cx43 plaques, which correlated negatively with cardiomegaly. We conclude that elevated TGF-β levels during T. cruzi infection promote heart fibrosis and disorganise gap junctions, possibly contributing to abnormal impulse conduction and arrhythmia that characterise severe cardiopathy in Chagas disease.