882 resultados para dominance parétienne
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Homozygosity has long been associated with rare, often devastating, Mendelian disorders, and Darwin was one of the first to recognize that inbreeding reduces evolutionary fitness. However, the effect of the more distant parental relatedness that is common in modern human populations is less well understood. Genomic data now allow us to investigate the effects of homozygosity on traits of public health importance by observing contiguous homozygous segments (runs of homozygosity), which are inferred to be homozygous along their complete length. Given the low levels of genome-wide homozygosity prevalent in most human populations, information is required on very large numbers of people to provide sufficient power. Here we use runs of homozygosity to study 16 health-related quantitative traits in 354,224 individuals from 102 cohorts, and find statistically significant associations between summed runs of homozygosity and four complex traits: height, forced expiratory lung volume in one second, general cognitive ability and educational attainment (P < 1 × 10(-300), 2.1 × 10(-6), 2.5 × 10(-10) and 1.8 × 10(-10), respectively). In each case, increased homozygosity was associated with decreased trait value, equivalent to the offspring of first cousins being 1.2 cm shorter and having 10 months' less education. Similar effect sizes were found across four continental groups and populations with different degrees of genome-wide homozygosity, providing evidence that homozygosity, rather than confounding, directly contributes to phenotypic variance. Contrary to earlier reports in substantially smaller samples, no evidence was seen of an influence of genome-wide homozygosity on blood pressure and low density lipoprotein cholesterol, or ten other cardio-metabolic traits. Since directional dominance is predicted for traits under directional evolutionary selection, this study provides evidence that increased stature and cognitive function have been positively selected in human evolution, whereas many important risk factors for late-onset complex diseases may not have been.
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This study is focused on the dominance exerted by the invasive Argentine ant over native ants in a coastal Mediterranean area. Theimpact of this invasive ant on native ant assemblages and its consequences on total ant biomass and on the intensity of habitat explorationwere evaluated. Foraging ants were observed and their trajectories recorded during 5-minute periods in two study zones, one invaded andthe other non-invaded. Ant species detected, ant worker abundance, ant biomass and the intensity of soil surface searching done by antswere compared between the two zones. The Argentine ant invasion provoked a drastic reduction of the ant species richness. Apparentlyonly one native ant species is able to coexist with the Argentine ant, the cryptic Plagiolepis pygmaea. Ant worker abundance was also modified after the invasion: the number of Argentine ant workers detected, which represented 92% of the invaded zone, was two times higher than the number of native ant workers detected in the non-invaded zone. The total ant biomass was inversely affected, becoming four times lower in the invaded zone highly dominated by Linepithema humile. The higher number of Argentine ant workers and their fast tempo of activity implied an alteration of the intensity of soil surface searching: scanning by the Argentine ants in the invaded zone was higher than that done by the native ants in the non-invaded zone, and the estimated time for a complete soil surface scan was 64 minutes in the invaded zone and 108 minutes in the non-invaded zone. Consequently, resources will be discovered faster by ants in the invaded zone than in the non-invaded zone. The increase of the mean temperature and the decrease of the relative humidity from May to August reduced the ant activity in the two study zones but this reduction was greater in the invaded zone
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En väsentlig fråga inom såväl lingvistiska som kognitiva teorier är, hur språket beskriver kausala relationer. I finskan finns det en speciell typ av kausativa verb avledda med suffixet (U)ttA som används för att uttrycka att handlingen i fråga utförs av någon annan än subjektreferenten, t.ex. Maija haetuttaa Matilla kirjastosta kirjan ’Maija låter Matti hämta boken från biblioteket’ och Matti juoksuttaa Maijan kaupunkiin ’Matti låter Maija springa till staden’. Syftet med denna avhandling var att med exempel av sociala dominansens kausativer undersöka ordbildningens natur samt begreppet ’socialt förorsakande’. För att beskriva avledningars regelbundna argumentstruktur i form av kopplingen mellan syntaxen och semantiken upprättades deras prototypiska strukturer. Dessa verb har emellertid också specifika användningsområden som framhäver variationer i sociala relationer. Säregna egenskaper hos den sociala dominansens kausativer inkluderades i undersökningen och definierades som konstruktioner. Konstruktionerna omfattar speciella syntaktiska och/eller semantiska element och utöver det också pragmatiska värderande implikationer. Uppbyggnaden av den sociala dimensionen hos de undersökta verben består av egenskaper förbundna med typen av förorsakande, argumentens agentiva egenskaper (aktivitet eller passivitet, dominans, kontroll, viljestyrdhet och ansvarighet) samt konventionaliserade attityder och tolkningar. Ett exempel på en s.k. 'tolkningskonstruktion’ är den negativa dominansens uttryck som i avhandlingen kallas Maktmissbrukskonstruktionen. Denna konstruktion inkluderar talarens starkt kritiska hållning till den uttryckta situationen, t.ex. Asiakas juoksuttaa lentoemäntää ’Kunden låter flygvärdinnan springa’. Dessa konstruktioner fyller en viktig funktion i språklig kommunikation: att beskriva avvikande av sociala normer och att foga expressivitet till budskapet. Metodologiskt kombinerar denna avhandling teorier som baseras på det aktuella språkbruket och teoretisk lingvistisk analys. Verbens samt konstruktionernas konceptuella lexikala struktur och prototypstrukturerna analyserades med hjälp av den konceptuella semantikens verktyg, som har utvecklats av Jackendoff, Nikanne och Pörn.
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The objective of the present study was to investigate the influence of the establishment of dominance relationships and social stress on plasma cortisol and metabolite levels in Nile tilapia (Oreochromis niloticus). During the 30-day experiment, the fish weighing 236 ± 29 g were kept in individual aquaria, except for two pairings lasting 6 h each. Blood samples were taken from the animals before and after pairing. Display, approach, attack, rebuff, chase flight, and coloration were carried out on days 16 and 30. Activities and behaviors characteristic of the establishment of dominance relationships were described. It was possible to classify all experimental fish (N = 30) as dominant or subordinate. No differences were detected between dominant (N = 15) and subordinate (N = 15) fish during isolation or after pairing in cortisol (isolated: 5.76 ± 0.98 vs 5.42 ± 0.63; paired: 10.94 ± 1.62 vs 11.21 ± 2.45 µg/dl), glucose (isolated: 60.02 ± 4.9 vs 67.85 ± 16.16; paired: 110.44 ± 15.72 vs 136.26 ± 22.46 mg/dl), triglyceride (isolated: 167.87 ± 5.06 vs 185.68 ± 7.24; paired: 210.85 ± 13.40 vs 221.82 ± 12.70 mg/dl) or total protein levels (isolated: 7.01 ± 0.42 vs 6.69 ± 0.59; paired: 9.21 ± 0.62 vs 9.51 ± 0.66 g/dl). However, when isolated (N = 30) and paired (N = 30) tilapia were compared, there were significant differences in cortisol and metabolite levels. The similar response presented by dominant and subordinate tilapia indicates that establishment of dominance relationships was a stressor for both groups.
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Dominance status among female marmosets is reflected in agonistic behavior and ovarian function. Socially dominant females receive submissive behavior from subordinates, while exhibiting normal ovulatory function. Subordinate females, however, receive agonistic behavior from dominants, while exhibiting reduced or absent ovulatory function. Such disparity in female fertility is not absolute, and groups with two breeding females have been described. The data reported here were obtained from 8 female-female pairs of captive female marmosets, each housed with a single unrelated male. Pairs were classified into two groups: "uncontested" dominance (UD) and "contested" dominance (CD), with 4 pairs each. Dominant females in UD pairs showed significantly higher frequencies (4.1) of agonism (piloerection, attack and chasing) than their subordinates (0.36), and agonistic behaviors were overall more frequently displayed by CD than by UD pairs. Subordinates in CD pairs exhibited more agonistic behavior (2.9) than subordinates in UD pairs (0.36), which displayed significantly more submissive (6.97) behaviors than their dominants (0.35). The data suggest that there is more than one kind of dominance relationship between female common marmosets. Assessment of progesterone levels showed that while subordinates in UD pairs appeared to be anovulatory, the degree of ovulatory disruption in subordinates of CD pairs was more varied and less complete. We suggest that such variation in female-female social dominance relationships and the associated variation in the degree and reliability of fertility suppression may explain variations of the reproductive condition of free-living groups of common marmosets.
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There has been and will continue to be substantial debate over how the international system can best be characterized. The objective of this paper is to demonstrate that the international system can best be characterized by the essential features of realism, but the use of realist policy prescriptions are inadequate when applied independently to deal with the threat of terrorism as it exists today. In order to demonstrate this an examination of realism in the international system, U.S. foreign policy, and case analysis of Afghanistan and Iraq will be undertaken to demonstrate that although realist policy prescriptions do have a role in dealing with modem transnational security threats, these prescriptions on their own are inadequate when dealing with terrorism.
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This paper studies the theoretical and empirical implications of monetary policy making by committee under three different voting protocols. The protocols are a consensus model, where super-majority is required for a policy change; an agenda-setting model, where the chairman controls the agenda; and a simple majority model, where policy is determined by the median member. These protocols give preeminence to different aspects of the actual decision making process and capture the observed heterogeneity in formal procedures across central banks. The models are estimated by Maximum Likehood using interest rate decisions by the committees of five central banks, namely the Bank of Canada, the Bank of England, the European Central Bank, the Swedish Riksbank, and the U.S. Federal Reserve. For all central banks, results indicate that the consensus model is statically superior to the alternative models. This suggests that despite institutionnal differences, committees share unwritten rules and informal procedures that deliver observationally equivalent policy decisions.
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Malgré le fait que le statut social soit reconnu comme ayant une forte influence sur l’aptitude, les facteurs affectant le statut social et les changements de ce statut demeurent peu connus. De plus, les études sur la dominance ayant un lien avec l’agressivité portent rarement sur des femelles. Nous étudierons ces aspects en utilisant Neolamprologus pulcher, un poisson à reproduction coopérative du lac Tanganyika. La probabilité d’ascension sociale était manipulée sur le terrain et les changements physiologiques et comportementaux, ainsi que le niveau plasmatique de testostérone, associé avec l’ascension à la dominance de femelles subordonnées étaient caractérisés. Le degré de coopération et la masse étaient supérieurs chez les femelles ascendantes par rapport aux femelles non-ascendantes d’un même groupe social. Après une semaine d’ascension sociale, les femelles ascendantes ne différaient pas comportementalement, mais différaient physiologiquement des femelles dominantes. Les femelles dominantes, ascendantes et subordonnées ne différaient pas quant au niveau de testostérone plasmatique. Comprendre les bénéfices des comportements coopératifs pour les subordonnés a longtemps posé un problème évolutif. Nos résultats impliquent que les comportements coûteux métaboliquement peuvent avoir été sélectionnés en améliorant l’aptitude future via l’héritage du territoire et du statut social. De plus, le degré de coopération pourrait être un signal de qualité détecté par les compétiteurs et les collaborateurs.
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Le squattage militant est étudié du point du vue du fonctionnement du marché immobilier et des principes de justice libérale. On montre que certains cas de vacance peuvent être considérés comme des défaillances du marché et que, sous certaines conditions, le squattage peut être pareto-améliorant. On examine ensuite le squattage du point de vue des principes de justice en considérant la question des goûts dispendieux, qui doit être relogé, l'éventualité du paiement d'un loyer et la base informationnelle requise pour le relogement.
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Resumen tomado de la publicaci??n. Resumen tambi??n en ingl??s
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Resumen tomado de la publicaci??n