1000 resultados para barn och ungdomar


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English abstract: Oak barrels and the medieval warm period in Satakunta

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Kirjoitus perustuu Suomalaisen Lakimiesyhdistyksen Lakimiespäivillä 5.10.2002 pidettyyn esitykseen

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Abstract:The rhetorical approach in political analysis: Chaim Perelman and Quentin Skinner on political rhetoric

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Abstract: Classifying regimes: on methods and methodology

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The arms race between predators and prey has led to morphological and behavioral adaptations. Different antipredator strategies can coexist within a population if each strategy is the result of a trade-off with competing demands. Antipredator behavior can be associated with morphological traits, like color patterns, either because in the context of sexual selection, coloration signals the ability to avoid predators or because coloration is a naturally selected trait useful in avoiding predators. Because in the barn owl (Tyto alba), heritable eumelanic plumage coloration is associated with the glucocorticoid-dependent response to stress, we tested whether antipredator behavior is also related to this trait. Compared with small-spotted nestlings, individuals displaying larger black spots hissed more intensely in the presence of humans, feigned death longer, had a lower breathing rate under stress, and were more docile when handled. Cross-fostering experiments showed that the covariation between the spot size and the duration of feigning death was inherited from the biological mother, whereas covariation between spot size and docility was inherited from the biological father. Our results confirm that melanin-based coloration is associated with suites of behavioral traits, which are under both genetic and environmental influence. Coloration can thus evolve as a direct or indirect response to predation, but it can also be a signal of antipredator strategies to potential mates.

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Vastine Martti Pekkasen ja Jukka Maalammen keskusteluun Tieteessä tapahtuu-lehdissä 7/2001, 1/2002, 2/2002 ja 3/2002

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Abstract Island biogeography has provided fundamental hypotheses in population genetics, ecology and evolutionary biology. Insular populations usually face different feeding conditions, predation pressure, intraspecific and interspecific competition than continental populations. This so-called island syndrome can promote the evolution of specific phenotypes like a small (or large) body size and a light (or dark) colouration as well as influence the evolution of sexual dimorphism. To examine whether insularity leads to phenotypic differentiation in a consistent way in a worldwide-distributed nonmigratory species, we compared body size, body shape and colouration between insular and continental barn owl (Tyto alba) populations by controlling indirectly for phylogeny. This species is suitable because it varies in pheomelanin-based colouration from reddish-brown to white, and it displays eumelanic black spots for which the number and size vary between individuals, populations and species. Females are on average darker pheomelanic and display more and larger eumelanic spots than males. Our results show that on islands barn owls exhibited smaller and fewer eumelanic spots and lighter pheomelanic colouration, and shorter wings than on continents. Sexual dimorphism in pheomelanin-based colouration was less pronounced on islands than continents (i.e. on islands males tended to be as pheomelanic as females), and on small islands owls were redder pheomelanic and smaller in size than owls living on larger islands. Sexual dimorphism in the size of eumelanic spots was more pronounced (i.e. females displayed much larger spots than males) in barn owls living on islands located further away from a continent. Our study indicates that insular conditions drive the evolution towards a lower degree of eumelanism, smaller body size and affects the evolution of sexual dichromatism in melanin-based colour traits. The effect of insularity was more pronounced on body size and shape than on melanic traits.

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Eumelanin and pheomelanin are the main endogenous pigments in animals and melanin-based coloration has multiple functions. Melanization is associated with major life-history traits, including immune and stress response, possibly because of pleiotropic effects of genes that control melanogenesis. The net effects on pheo- versus eumelanization and other life-history traits may depend on the antagonistic effects of the genes that trigger the biosynthesis of either melanin form. Covariation between melanin-based pigmentation and fitness traits enforced by pleiotropic genes has major evolutionary implications particularly for socio-sexual communication. However, evidence from non-model organisms in the wild is limited to very few species. Here, we tested the hypothesis that melanin-based coloration of barn swallow (Hirundo rustica) throat and belly feathers covaries with acquired immunity and activation of the hypothalamic-pituitary-adrenal (HPA) axis, as gauged by corticosterone plasma levels. Individuals of both sexes with darker brownish belly feathers had weaker humoral immune response, while darker males had higher circulating corticosterone levels only when parental workload was experimentally reduced. Because color of belly feathers depends on both eu- and pheomelanin, and its darkness decreases with an increase in the concentration of eu- relative to pheomelanin, these results are consistent with our expectation that relatively more eu- than pheomelanized individuals have better immune response and smaller activation of the HPA-axis. Covariation of immune and stress response arose for belly but not throat feather color, suggesting that any function of color as a signal of individual quality or of alternative life-history strategies depends on plumage region.

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Abstract: Religion and democracy: Protestantism, Catholicism and Islam in comparative perspective

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Abstract: Sequences of democratisation and democratic stability in the third wave of democratisation

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The Zeman Barn (86-00028) is an early twentieth-century example of a gothic roofed barn and is part of the Zeman Farmstead located along U.S. Highway 30 in Otter Creek Township (Township 38N, Range 14W), Tama County, Iowa (Figures 1 and 2). The farmstead was initially evaluated in a reconnaissance architectural survey conducted in 1998 by The Louis Berger Group, Inc (Berger). An intensive architectural survey of the property by Berger’s Principal Architectural Historian, Martha H. Bowers, evaluated the farmstead as not being eligible for listing in the National Register of Historic Places (National Register) but noted that the barn appears to be eligible for listing in the National Register under Criterion C (Bowers 1998). At the request of the Iowa Department of Transportation, Berger completed the recordation project to provide a documentary record of the Zeman Barn in accordance with the guidelines set forth by the Iowa State Historic Preservation Office regarding historic property studies for barns. Background research for this project was conducted in September 2008 and April 2009. The property was inspected and photographed in May 2008. Information on the property was gathered through background research, interviews with Zeman family members, field investigation, and photo documentation. Historical maps of the project area were used to collect data necessary for developing regional and local historic contexts. The research for this report was conducted at the Tama County Courthouse and the Tama County Historical Museum Genealogical Library, both in Toledo. Much of the background research for the project was conducted by Camilla Deiber and Michael Dulle. Ms. Deiber also prepared the photographic documentation, plan drawings, and the graphics used in this report. Mr. Roger L. Ciuffo conducted interviews with Zeman family members and wrote this report.