937 resultados para particular inheritance regimes
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The weak selection approximation of population genetics has made possible the analysis of social evolution under a considerable variety of biological scenarios. Despite its extensive usage, the accuracy of weak selection in predicting the emergence of altruism under limited dispersal when selection intensity increases remains unclear. Here, we derive the condition for the spread of an altruistic mutant in the infinite island model of dispersal under a Moran reproductive process and arbitrary strength of selection. The simplicity of the model allows us to compare weak and strong selection regimes analytically. Our results demonstrate that the weak selection approximation is robust to moderate increases in selection intensity and therefore provides a good approximation to understand the invasion of altruism in spatially structured population. In particular, we find that the weak selection approximation is excellent even if selection is very strong, when either migration is much stronger than selection or when patches are large. Importantly, we emphasize that the weak selection approximation provides the ideal condition for the invasion of altruism, and increasing selection intensity will impede the emergence of altruism. We discuss that this should also hold for more complicated life cycles and for culturally transmitted altruism. Using the weak selection approximation is therefore unlikely to miss out on any demographic scenario that lead to the evolution of altruism under limited dispersal.
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Este Proyecto Fin de Carrera, pertenece al área de 'Competencias profesionales' y tiene como objetivo el análisis de diversas experiencias de enseñanza-aprendizaje y de evaluación de competencias transversales, haciendo hincapié en la competencia de la comunicación escrita, dentro de la formación de currículos TIC. El análisis se centra en los planes de estudios del Grado en Ingeniería Informática de 10 universidades españolas representativas (públicas, privadas y a distancia) como representación de la "nueva" formación de currículos TIC en nuestra sociedad.
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Estudi comparatiu de les faules mitològiques burlesques catalanes barroques i les produccions del mateix gènere en diferents literatures romàniques. Mitjançant aquest plantejament, es vol reivindicar la participació activa dels autors catalans en la modernitat de l'època barroca.
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Background. In cardiopulmonary bypass (CPB) patients, fibrinolysis may enhance postoperative inflammatory response. We aimed to determine whether an additional postoperative dose of antifibrinolytic tranexamic acid (TA) reduced CPB-mediated inflammatory response (IR). Methods. We performed a randomized, double-blind, dose-dependent, parallel-groups study of elective CPB patients receiving TA. Patients were randomly assigned to either the single-dose group (40 mg/Kg TA before CPB and placebo after CPB) or the double-dose group (40 mg/Kg TA before and after CPB). Results. 160 patients were included, 80 in each group. The incident rate of IR was significantly lower in the double-dose-group TA2 (7.5% vs. 18.8% in the single-dose group TA1; P = 0.030). After adjusting for hypertension, total protamine dose and temperature after CPB, TA2 showed a lower risk of IR compared with TA1 [OR: 0.29 (95% CI: 0.10-0.83), (P = 0.013)]. Relative risk for IR was 2.5 for TA1 (95% CI: 1.02 to 6.12). The double-dose group had significantly lower chest tube bleeding at 24 hours [671 (95% CI 549-793 vs. 826 (95% CI 704-949) mL; P = 0.01 corrected-P significant] and lower D-dimer levels at 24 hours [489 (95% CI 437-540) vs. 621(95% CI: 563-679) ng/mL; P = 0.01 corrected-P significant]. TA2 required lower levels of norepinephrine at 24 h [0.06 (95% CI: 0.03-0.09) vs. 0.20(95 CI: 0.05-0.35) after adjusting for dobutamine [F = 6.6; P = 0.014 corrected-P significant]. We found a significant direct relationship between IL-6 and temperature (rho = 0.26; P < 0.01), D-dimer (rho = 0.24; P < 0.01), norepinephrine (rho = 0.33; P < 0.01), troponin I (rho = 0.37; P < 0.01), Creatine-Kinase (rho = 0.37; P < 0.01), Creatine Kinase-MB (rho = 0.33; P < 0.01) and lactic acid (rho = 0.46; P < 0.01) at ICU arrival. Two patients (1.3%) had seizure, 3 patients (1.9%) had stroke, 14 (8.8%) had acute kidney failure, 7 (4.4%) needed dialysis, 3 (1.9%) suffered myocardial infarction and 9 (5.6%) patients died. We found no significant differences between groups regarding these events. Conclusions. Prolonged inhibition of fibrinolysis, using an additional postoperative dose of tranexamic acid reduces inflammatory response and postoperative bleeding (but not transfusion requirements) in CPB patients. A question which remains unanswered is whether the dose used was ideal in terms of safety, but not in terms of effectiveness.
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In this study, we looked at the inheritance of susceptibility and resistance to Schistosoma mansoni infection in the first generation of crossbred Biomphalaria alexandrina snails. Our ultimate goal is to use such information to develop a biological method of controlling schistosomiasis. We infected laboratory-bred snails with S. mansoni miracidia and examined cercarial shedding to determine susceptibility and resistance. Five parental groups were used: Group I contained 30 susceptible snails, Group II contained 30 resistant snails, Group III contained 15 susceptible and 15 resistant snails, Group IV contained 27 susceptible and three resistant snails and Group V contained three susceptible and 27 resistant snails. The percentage of resistant snails in the resulting progeny varied according to the ratio of susceptible and resistant parents per group; they are 7%, 100%, 68%, 45% and 97% from Groups I, II, III, IV and V, respectively. On increasing the percentage of resistant parent snails, the percentage of resistant progeny increased, while cercarial production in their susceptible progeny decreased.
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La station touristique représente un espace urbain consacré principalement au tourisme, tout en comprenant également une population résidente permanente. Du point de vue de la gestion des réseaux urbains de l'eau, cette caractéristique induit pour ce type de lieu des usages propres à tout espace urbain mais également des spécificités liées à la forte fluctuation saisonnière de la population résidente ou encore à la présence d'usages particuliers tels que l'irrigation des golfs, la production de neige artificielle ou le thermalisme. Dès lors, la planification de l'approvisionnement est délicate et peu prévisible. Ces difficultés sont renforcées par le fait que les concentrations temporelles de la demande coïncident généralement avec des périodes de stress hydrique notable. Dans le cas de stations balnéaires, les pics de fréquentation interviennent en général durant l'été lorsque la ressource en eau est peu disponible. Le problème est similaire dans les stations touristiques de montagne où l'eau est généralement indisponible car stockée sous forme de neige durant les mois de forte fréquentation. De plus, ces difficultés sont souvent renforcées par la localisation géographique des stations touristiques, fréquemment situées dans des espaces sensibles du point de vue de la ressource en eau, avec des situations de pénuries temporelles, voire structurelles. Ces problématiques propres à la plupart des stations touristiques mènent souvent à de fortes rivalités entre, d'une part, les différents usages touristiques de la ressource, et d'autre part, les usages autochtones et touristiques. Les particularités liées au tourisme tendent ainsi à renforcer les rivalités entre différents types de secteurs d'activité (approvisionnement en eau potable, tourisme, hydroélectricité, enneigement artificiel, irrigation, etc.). Ces différents usages de la ressource mis en concurrence nécessitent dès lors la mise en oeuvre de réglementations structurées à travers des politiques publiques ainsi que des droits de propriété et selon des composantes nationales, régionales et locales ; soit un cadre institutionnel que nous proposons d'appeler Régime Institutionnel de Ressource (RIR) (Knoepfel et al. 2001, 2007). A travers cette thèse de doctorat, nous répondons à différentes questions de recherche. Nous tentons d'abord de comprendre comment ces différents RIR sont-ils mis en oeuvre dans le cadre d'espaces touristiques ? Comment ceux-ci sont-ils concrétisés par les acteurs et quels sont leurs effets en termes de durabilité technique, environnementale, sociale et économique des réseaux urbains de l'eau ? Nous questionnons ensuite les effets du tourisme sur la gestion des infrastructures de réseau à l'échelle de la station touristique et de son bassin versant et nous interrogeons sur les effets du tourisme en termes de gestion des eaux urbaines. Nous portons notre attention sur deux stations touristiques situées dans deux contextes institutionnels différents (Crans-Montana en Suisse et Morzine-Avoriaz en France) et y étudions trois types de régimes institutionnels en particulier : la régie directe (gestion publique), l'affermage (gestion déléguée) et la gestion privée des infrastructures. Les résultats de cette thèse de doctorat indiquent tout d'abord dans quelle mesure le tourisme modifie de façon significative la perception et les modalités de gestion de la ressource en eau et des infrastructures. Ils montrent ensuite que l'espace fonctionnel de la gestion de ces infrastructures correspond rarement aux limites du réseau hydrographique naturel et quelles en sont les implications en termes de durabilité. Enfin, la comparaison de différents régimes institutionnels révèle les forces et les faiblesses de chaque modèle de gestion dans le cas spécifique des stations touristiques et également les différentes solutions adoptées localement pour la mise en oeuvre d'un arrangement institutionnel permettant un usage plus ou moins durable des infrastructures de réseau et du réseau hydrographique naturel. - Tourism resort represents an urban area mainly dedicated to tourism while including at the same time a permanent residential population. From the point of view of urban water networks, this characteristic induces a strong seasonal fluctuation of residential population and involves special water uses such as golf irrigation, production of artificial snow or functioning of thermal baths. Therefore, water supply planning can be tricky and difficult to predict. These difficulties are reinforced by the fact that temporary concentrations of water demand coïncidé generally with periods of water stress. In the case of seaside resorts, frequenting peaks arise in general during summer when water resource is less available. The problem is similar in mountainous tourist resorts where water is generally unavailable as it is stored as snow during months of highest frequenting. Furthermore, these difficulties are often reinforced by resorts' geographical localisations, which are often situated in sensitive areas in terms of temporary or structural water shortages. These problematic issues often lead to strong rivalries between tourists' water uses on the one hand, and between locals and tourists uses on the other hand. Thus, features of tourism tend to reinforce rivalries between different sectors of activity (supply of drinking water, tourism, hydroelectricity, artificial snow, irrigation, etc.). These different and competing water uses need the implementation of rules structured through public policies and property rights and through national, regional and local legal components; We propose to call this framework as an Institutional Resource Regime (IRR) (Knoepfel et al. 2001, 2007, 2009). Through this PhD thesis, we answer different research questions. We firstly aim to understand how those different IRR are implemented within tourism spaces? How do actors materialize them and what are their effects in term of technical, environmental, social and economical sustainability of urban water networks? We then, investigate effects of tourism on water networks infrastructures' management at the scale of the tourist resort and its river basin. We focus our attention on two tourist resorts situated within two different institutional contexts (Crans-Montana, Switzerland and Morzine-Avoriaz, France) and study three types of institutional regime in particular: public, delegated and private management of infrastructures. Results of this PhD thesis indicate firstly how tourism modifies in a significant way the perception and management modalities of water resource and infrastructures. Results also show that functional space of infrastructures management rarely matches with the limits of the natural river basin and indicates what it means in terms of sustainability. Finally, the comparison of different institutional regimes reveals the strengths and weakness of each management model in the specific case of tourist resorts and shows the different solutions in locally implementing an institutional arrangement for a more or less sustainable management of network infrastructures and natural water system.
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Natural populations are of finite size and organisms carry multilocus genotypes. There are, nevertheless, few results on multilocus models when both random genetic drift and natural selection affect the evolutionary dynamics. In this paper we describe a formalism to calculate systematic perturbation expansions of moments of allelic states around neutrality in populations of constant size. This allows us to evaluate multilocus fixation probabilities (long-term limits of the moments) under arbitrary strength of selection and gene action. We show that such fixation probabilities can be expressed in terms of selection coefficients weighted by mean first passages times of ancestral gene lineages within a single ancestor. These passage times extend the coalescence times that weight selection coefficients in one-locus perturbation formulas for fixation probabilities. We then apply these results to investigate the Hill-Robertson effect and the coevolution of helping and punishment. Finally, we discuss limitations and strengths of the perturbation approach. In particular, it provides accurate approximations for fixation probabilities for weak selection regimes only (Ns < or = 1), but it provides generally good prediction for the direction of selection under frequency-dependent selection.
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The influence of public policy, property rights and contracts on the sustainability of residential buildings remains largely unknown. This research will use the analytical framework of the housing institutional regime to study the sustainability over time of the housing stock. We aim to produce an inventory of the housing institutional regime in Switzerland, a comparison with the German and Catalan regimes, and policy suggestions to achieve a better sustainability of the housing stock.
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In Arabidopsis thaliana, gene expression level polymorphisms (ELPs) between natural accessions that exhibit simple, single locus inheritance are promising quantitative trait locus (QTL) candidates to explain phenotypic variability. It is assumed that such ELPs overwhelmingly represent regulatory element polymorphisms. However, comprehensive genome-wide analyses linking expression level, regulatory sequence and gene structure variation are missing, preventing definite verification of this assumption. Here, we analyzed ELPs observed between the Eil-0 and Lc-0 accessions. Compared with non-variable controls, 5' regulatory sequence variation in the corresponding genes is indeed increased. However, approximately 42% of all the ELP genes also carry major transcription unit deletions in one parent as revealed by genome tiling arrays, representing a >4-fold enrichment over controls. Within the subset of ELPs with simple inheritance, this proportion is even higher and deletions are generally more severe. Similar results were obtained from analyses of the Bay-0 and Sha accessions, using alternative technical approaches. Collectively, our results suggest that drastic structural changes are a major cause for ELPs with simple inheritance, corroborating experimentally observed indel preponderance in cloned Arabidopsis QTL.
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Este estudo teve como objetivo levantar o perfil dos candidatos ao curso técnico de enfermagem de uma Escola de Enfermagem Particular da cidade de São Paulo. A população consta de indivíduos adultos jovens; com idade média de 31,09 anos; com renda familiar de 9,65 salários mínimos; solteiro; predominância do sexo feminino; 12,5% deles com formação escolar superior incompleto ou completo; 43,8% tem filhos, cujas idades variam entre 6 e 13 anos. Os candidatos apresentam afinidade para trabalhar com pacientes graves e sem afinidade para assistência pediátrica. Do trabalho em oncologia, o aprendizado pessoal é fator positivo em oposição ao sofrimento pessoal e do paciente, que é considerado aspecto negativo.
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Este estudo descritivo e exploratório teve como objetivo analisar as facilidades e dificuldades referidas por quinze alunos de cursos de especialização em enfermagem, em relação ao processo de ensino da disciplina Métodos de Investigação Cientifica, focalizado no referencial do paradigma do agir comunicativo. As categorias expressas, como facilidades e dificuldades, em relação ao conteúdo da disciplina, elaboração do projeto de pesquisa e seu desenvolvimento, foram analisadas segundo os tipos padronizados de ação comunicativa. Após a análise, pode-se perceber a emersão de elementos em diferentes níveis de desenvolvimento e interpretados numa seqüência de formas de comunicação, destacando-se por não permitir vislumbrar um compromisso com a inovação ou mudança do processo de ensino, demonstrando as perturbações do consenso neste processo.
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Estudi realitzat a partir d’una estada a la University of Oxford, Gran Bretanya, entre 2010 i 2012. Durant l’estada postdoctoral a la University of Oxford s’han efectuat dos estudis relacionats amb l’onomàstica dels faraons d’Egipte i que constitueixen una continuació de l’anàlisi de la titulatura d’Alexandre el Gran realitzada prèviament per l’investigador en la seva recerca doctoral. El primer estudi examina la titulatura faraònica dels emperadors romans en comparació amb la d’Alexandre i, en especial, la significació ideològica i política dels paral•lelismes onomàstics existents entre elles, els quals han estat analitzats en el marc de la imitatio-aemulatio-comparatio Alexandri. Per al cas d’August, s’ha arribat a la conclusió que l’adopció de determinats apel•latius egipcis utilitzats anteriorment per Alexandre pot ser interpretada com un exemple local o estrictament egipci d’imitatio Alexandri, mentre que, en relació amb la resta d’emperadors, atès que les seves titulatures faraòniques es basen o imiten la del primer emperador, aquestes represes han de ser vistes més aviat com un exemple d’imitatio (o comparatio) Augusti. El segon estudi versa sobre la titulatura faraònica egípcia i la tradició annalística. A partir d’una anàlisi comparativa dels protocols onomàstics dels fundadores de cadascuna de les dinasties, s’ha intentat determinar si determinats noms o epítets s’empren de forma recurrent i d’una manera deliberada per tal de senyalar canvis dinàstics, és a dir, noves realitats polítiques. En concret, s’ha pretès establir fins a quin punt determinats recursos onomàstics tenen el seu reflex en la divisió en dinasties de Manetó i, alhora, determinar en quina mesura l’estudi de l’onomàstica faraònica pot contribuir al coneixement de com els egipcis conceptualitzaren i organitzaren el seu propi passat.
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A generic LC-MS approach for the absolute quantification of undigested peptides in plasma at mid-picomolar levels is described. Nine human peptides namely, brain natriuretic peptide (BNP), substance P (SubP), parathyroid hormone 1-34 (PTH), C-peptide, orexines A and B (Orex-A and -B), oxytocin (Oxy), gonadoliberin-1 (gonadothropin releasing-hormone or luteinizing hormone-releasing hormone, LHRH) and α-melanotropin (α-MSH) were targeted. Plasma samples were extracted via a 2-step procedure: protein precipitation using 1vol of acetonitrile followed by ultrafiltration of supernatants on membranes with a MW cut-off of 30 kDa. By applying a specific LC-MS setup, large volumes of filtrates (e.g., 2×750 μL) were injected and the peptides were trapped on a 1mm i.d.×10 mm length C8 column using a 10× on-line dilution. Then, the peptides were back-flushed and a second on-line dilution (2×) was applied during the transfer step. The refocalized peptides were resolved on a 0.3mm i.d. C18 analytical column. Extraction recovery, matrix effect and limits of detection were evaluated. Our comprehensive protocol demonstrates a simple and efficient sample preparation procedure followed by the analysis of peptides with limits of detection in the mid-picomolar range. This generic approach can be applied for the determination of most therapeutic peptides and possibly for endogenous peptides with latest state-of-the-art instruments.