993 resultados para Inter-genotype competition


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Recent research in industrial organisation has investigated the essential place that middlemen have in the networks that make up our global economy. In this paper we attempt to understand how such middlemen compete with each other through a game theoretic analysis using novel techniques from decision-making under ambiguity.
We model a purposely abstract and reduced model of one middleman who provides a two-sided platform, mediating surplus-creating interactions between two users. The middleman evaluates uncertain outcomes under positional ambiguity, taking into account the possibility of the emergence of an alternative middleman offering intermediary services to the two users.
Surprisingly, we find many situations in which the middleman will purposely extract maximal gains from her position. Only if there is relatively low probability of devastating loss of business under competition, the middleman will adopt a more competitive attitude and extract less from her position.

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The brain derived neurotrophic factor (BDNF) Val66Met polymorphism and stimulation duration are thought to play an important role in modulating motor cortex plasticity induced by non-invasive brain stimulation (NBS). In the present study we sought to determine whether these factors interact or exert independent effects in older adults. Fifty-four healthy older adults (mean age = 66.85 years) underwent two counterbalanced sessions of 1.5 mA anodal transcranial direct current stimulation (atDCS), applied over left M1 for either 10 or 20 min. Single pulse transcranial magnetic stimulation (TMS) was used to assess corticospinal excitability (CSE) before and every 5 min for 30 min following atDCS. On a group level, there was an interaction between stimulation duration and BDNF genotype, with Met carriers (n = 13) showing greater post-intervention potentiation of CSE compared to Val66Val homozygotes homozygotes (n = 37) following 20 min (p = 0.002) but not 10 min (p = 0.219) of stimulation. Moreover, Met carriers, but not Val/Val homozygotes, exhibited larger responses to TMS (p = 0.046) after 20 min atDCS, than following 10 min atDCS. On an individual level, two-step cluster analysis revealed a considerable degree of inter-individual variability, with under half of the total sample (42%) showing the expected potentiation of CSE in response to atDCS across both sessions. Intra-individual variability in response to different durations of atDCS was also apparent, with one-third of the total sample (34%) exhibiting LTP-like effects in one session but LTD-like effects in the other session. Both the inter-individual (p = 0.027) and intra-individual (p = 0.04) variability was associated with BDNF genotype. In older adults, the BDNF Val66Met polymorphism along with stimulation duration appears to play a role in modulating tDCS-induced motor cortex plasticity. The results may have implications for the design of NBS protocols for healthy and diseased aged populations.

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The adaptor protein-2 sigma subunit (AP2sigma;2) is pivotal for clathrin-mediated endocytosis of plasma membrane constituents such as the calcium-sensing receptor (CaSR). Mutations of the AP2sigma;2 Arg15 residue result in familial hypocalciuric hypercalcaemia type 3 (FHH3), a disorder of extracellular calcium (Ca<inf>o</inf><sup>2+</sup>) homeostasis. To elucidate the role of AP2sigma;2 in Ca<inf>o</inf><sup>2+</sup> regulation, we investigated 65 FHH probands, without other FHH-associated mutations, for AP2sigma;2 mutations, characterized their functional consequences and investigated the genetic mechanisms leading to FHH3. AP2sigma;2 mutations were identified in 17 probands, comprising 5 Arg15Cys, 4 Arg15His and 8 Arg15Leu mutations. A genotype-phenotype correlation was observed with the Arg15Leu mutation leading to marked hypercalcaemia. FHH3 probands harboured additional phenotypes such as cognitive dysfunction. All three FHH3-causing AP2sigma;2 mutations impaired CaSR signal transduction in a dominant-negative manner. Mutational bias was observed at the AP2sigma;2 Arg15 residue as other predicted missense substitutions (Arg15Gly, Arg15Pro and Arg15Ser), which also caused CaSR loss-of-function, were not detected in FHH probands, and these mutations were found to reduce the numbers of CaSR-expressing cells. FHH3 probands had significantly greater serum calcium (sCa) and magnesium (sMg) concentrations with reduced urinary calcium to creatinine clearance ratios (CCCR) in comparison with FHH1 probands with CaSR mutations, and a calculated index of sCa × sMg/100 × CCCR, which was ≥ 5.0, had a diagnostic sensitivity and specificity of 83 and 86%, respectively, for FHH3. Thus, our studies demonstrate AP2sigma;2 mutations to result in a more severe FHH phenotype with genotype-phenotype correlations, and a dominant-negative mechanism of action with mutational bias at the Arg15 residue.

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The stock structure of turbot was investigated between samples from S-Norway, the Irish Sea and the Kattegat, using 12 microsatellite loci and compared to the turbot caught in Icelandic waters. Highly significant genetic differentiation was observed between samples from Kattegat and other areas. Significant genetic differentiation was also observed between the Irish Sea sample on one hand and Iceland and S-Norway on the other hand. No significant genetic differentiation was observed between Iceland and S-Norway. Otoliths of 25 turbot, age ranging from 3 to 19 years, were subjected to nearly 300 mass spectrometry determinations of stable oxygen and carbon isotopes. Oxygen isotope composition (δ18O) in the otolith samples was used to estimate ambient temperature at time of otolith accretion, and yielded estimated temperatures experienced by the turbot ranging from 3 to 15°C. Overall, the genetic analysis indicates panmixia between turbot in Icelandic and Norwegian waters. While the extensive migration of larvae between Norway and Iceland is unlikely, passive drift of turbot larva from other areas (e.g. Ireland) cannot be ruled out. 

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Making Ireland Modern is a cross-disciplinary, inter-institutional, inter-media design and research project which emerged from an open competition (won by Boyd and McLaughlin) to commission/curate the Irish pavilion for the Venice biennale 2014. It explores the relationship between architecture, infrastructure and technology in the building of a new nation. Constructed as a demountable, open matrix of drawings, photographs, models and other artefacts, the exhibition (12 x 5 x 6 metres) presents ten infrastructural episodes – Negation, Electricity, Health, Transportation, Television, Aviation, Education, Telecommunications, Motorways, Data – spanning a period of one hundred years from 1916-2016. Exploring a range of scales from the detail design of objects to entire landscapes and other territories, Making Ireland Modern describes architecture’s role in transforming the physical and cultural identity of the new state through its intersession in the everyday lives of its population. In 2015, we were commissioned by the Arts Council of Ireland to expand and develop the pavilion for a three cities tour of Ireland as one of the five major strands of the Arts Council’s Art2016 programme of Irish State’s 1916-2016 centennial celebrations (2016).

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Many wildlife studies use chemical analyses to explore spatio-temporal variation in diet, migratory patterns and contaminant exposure. Intrinsic markers are particularly valuable for studying non-breeding marine predators, when direct methods of investigation are rarely feasible. However, any inferences regarding foraging ecology are dependent upon the time scale over which tissues such as feathers are formed. In this study, we validate the use of body feathers for studying non-breeding foraging patterns in a pelagic seabird, the northern fulmar. Analysis of carcasses of successfully breeding adult fulmars indicated that body feathers moulted between September and March, whereas analyses of carcasses and activity patterns suggested that wing feather and tail feather moult occurred during more restricted periods (September to October and September to January, respectively). By randomly sampling relevant body feathers, average values for individual birds were shown to be consistent. We also integrated chemical analyses of body feather with geolocation tracking data to demonstrate that analyses of δ13C and δ15N values successfully assigned 88 % of birds to one of two broad wintering regions used by breeding adult fulmars from a Scottish study colony. These data provide strong support for the use of body feathers as a tool for exploring non-breeding foraging patterns and diet in wide-ranging, pelagic seabirds.

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Analgesics which affect prostaglandin (PG) pathways are used by most pregnant women. As germ cells (GC) undergo developmental and epigenetic changes in fetal life and are PG targets, we investigated if exposure of pregnant rats to analgesics (indomethacin or acetaminophen) affected GC development and reproductive function in resulting offspring (F1) or in the F2 generation. Exposure to either analgesic reduced F1 fetal GC number in both sexes and altered the tempo of fetal GC development sex-dependently, with delayed meiotic entry in oogonia but accelerated GC differentiation in males. These effects persisted in adult F1 females as reduced ovarian and litter size, whereas F1 males recovered normal GC numbers and fertility by adulthood. F2 offspring deriving from an analgesic-exposed F1 parent also exhibited sex-specific changes. F2 males exhibited normal reproductive development whereas F2 females had smaller ovaries and reduced follicle numbers during puberty/adulthood; as similar changes were found for F2 offspring of analgesic-exposed F1 fathers or mothers, we interpret this as potentially indicating an analgesic-induced change to GC in F1. Assuming our results are translatable to humans, they raise concerns that analgesic use in pregnancy could potentially affect fertility of resulting daughters and grand-daughters.

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Este trabalho de investigação centra-se na importância do conhecimento da inter (ligação) entre a Biblioteca Escolar/Centro de Recursos Educativos e o currículo. A problemática da investigação é lançada pela questão que constitui o ponto de partida deste trabalho: “ De que forma é que a Biblioteca Escolar/Centro de Recursos Educativos interage com o Currículo como um recurso do processo de ensino-aprendizagem? “ Tendo como base esta problemática, o corpo da dissertação é constituída por duas panes. A primeira respeitante ao quadro teórico e a segunda referente ao estudo empírico. No quadro teórico procedemos a uma aproximação conceptual à problemática em estudo. Tecemos considerações acerca da evolução da biblioteca escolar, conhecendo igualmente os princípios e as formas de atuar do Programa Rede de Bibliotecas Escolares e a principal legislação sobre este assunto. Refletimos acerca do currículo do ensino pré-escolar e do 1° ciclo do ensino básico, níveis com os quais realizámos a componente empírica do trabalho, identificando a Biblioteca Escolar/Centro de Recursos Educativos como constituindo um recurso fundamental no processo de ensino aprendizagem, no contexto da diferenciação curricular, chamando igualmente a atenção para a importância das parcerias no âmbito da articulação entre o ambiente educacional e o território. A dimensão empírica da pesquisa envolveu a conceção e a testagem de instrumentos de recolha de dados, nomeadamente a análise documental, a observação direta em contexto de Biblioteca Escolar, a realização de entrevistas semi-directivas e a aplicação de um inquérito por questionário aos alunos do 1° ciclo do ensino básico. O conhecimento produzido permitiu-nos responder à problemática objetivada no início da investigação, evidenciando que a Biblioteca Escolar/Centro de Recursos Educativos interage com o Currículo como um recurso do processo de ensino aprendizagem, constituindo-se como um centro de motivação da comunidade educativa que potencia um conjunto de aprendizagens das quais se destacam a leitura e a escrita e as atividades de pesquisa, através da metodologia de projeto. A BE/CRE complementa e enriquece o trabalho da sala de aula, quer ao nível das áreas curriculares disciplinares, quer ao nível das áreas curriculares não disciplinares. Com base nas conclusões resultantes da investigação empírica, terminámos com a formulação de algumas sugestões e recomendações que a evolução do estudo nos foi aconselhando. /ABSTRACT - This research work focuses the importance of the school library/educational resource centre and its connection with the school curriculum. The research was focussed on the following question: “How can the school library/educational resource Centre interact with the curriculum as a teaching resource?” Based on this question, the dissertation includes two distinctive parts. The former concerns the theoretical framework and the latter the empirical study case. As far as the theoretical framework is concerned, we have studied the conceptual facts and drew some major conclusions about the evolution of the school library, taking into account the rules and proceedings of the School Library Network Programme and the legislation on the issue. We went through the curriculum of the kindergarten and the primary school on which we developed our study case. The school library/educational resource centre was, therefore, identified as a fundamental resource in the learning/teaching process for the curricula differentiation. We also emphasized the importance of partnerships to enhance the articulation between the educational environment and school territory. The empirical research included both the conception and the testing of some important data collecting techniques, namely the documentary analysis, direct observation in a School Library, half-directed interviews and a questionnaire which was answered by primary school students. The knowledge acquired allowed us to find possible answers for the question we have asked at the beginning of our research. We can conclude that the School Library/Educational Resource Centre does interact with the curriculum as motivation to improve the process of learning, such as reading and writing, of the educational community. The project work also gains a new perspective as the school library/educational resource centre enriches and complements the classroom work both on the curriculum subjects and non- subject curricular areas. Based on the conclusions we drew from our study case, we make suggestions and recommendations for further research.