987 resultados para Berti, Giovanni Lorenzo, 1696-1766.


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The Alagoas Curassow Mitu mitu is considered extinct in the wild. Since 1979, two females and a male caught in the wild have bred successfully in captivity, and, in 1990, hybridizations between M. mitu and Razor-billed Mitu M. tuberosum were performed. By June 2008, there were around 130 living birds in two different aviaries. We sequenced two regions of the mitochondrial DNA of both captive stocks of Alagoas Curassows. We unequivocally identified hybrids that have haplotype typical of M. tuberosum. However, unless the original studbook can be recovered there is no confident way to discriminate ""pure"" M. mitu birds for breeding and reintroduction purposes. Allied with morphological data gathered in an independent study, we suggest that conservation actions need to focus on specimens with diagnostic phenotypic characters of M. mitu, and avoid birds with mitochondria, genetic contribution of M. tuberosum. Although we have detected low levels of genetic variability among captive birds, the steady increase of the captive population suggests that inbreeding depression and hybridization are not a reproductive hindrance. Reintroduction of some of these potential hybrid birds in the original area of occurrence of the Alagoas Curassow may be the only hope to fill in the ecological niche left vacant. An educational program involving local communities to conserve future reintroduction of curassows and their restored habitat is highly recommended. Accepted 12 November 2009.

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Analisi di alcuni termini svedesi presenti nelle lettere di Lorenzo Adami, inviato nel 1665 a Stoccolma dalla regina Cristina di Svezia.

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The complexes [Hpy][Cu(H3L)(H2O)] 1 (L6 = nitrilotrimethylenetrisphosphonate) and [Cu(HL°)(py)]2·2Me2CO 2 [(L°)3 = P,P,P" -triphenylnitrilotrismethylenetrisphosphinate)] have been isolated and characterized by X-ray crystallography, near IR-visible spectroscopy and magnetic measurements. The structure determination has shown the complexes to be constituted by monomeric and dimeric units respectively. In the monomer the metal atom is surrounded by the phosphonate ligand and a water molecule, with a geometry between a trigonal bipyramid and a square pyramid. The two copper atoms in the dimer are held together by an arm of the tripod ligand, with a pyridine molecule as additional ligand, and display octahedral geometry. The presence of monomeric and dimeric species in aqueous solutions of 1 and 2 has been shown by ESMS studies. The formation in water solution of the dimer [{Cu(H3L)}2]2-, as a minor species, has been supported by potentiometric measurements, whereas only the monomeric anion [CuL°] has been ascertained to be present. In general the ligand H3L° forms less stable copper(II) complexes than H6L.


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Contemporary studies of sea turtle diving behaviour are generally based upon sophisticated techniques such as the attachment of time depth recorders. However, if the risks of misinterpretation are to be minimized, it is essential that electronic data are analysed in the light of first-hand observations. To this aim, we set out to make observations of juvenile hawksbill turtles (Eretmochelys imbricata, Linnaeus, 1766) foraging and resting in a shallow water coral reef habitat around the granitic Seychelles (4°'S, 55°'E). Data were collected from six study sites characterized by a shallow reef plateau (<5 m) and a flat sandy area at the base of the reef face (<10 m). Observation data were categorized into the following behaviours: (1) stationary foraging; (2) active foraging; (3) resting; and (4) assisted resting. Central to this investigation was the development of a technique for accurately estimating the size of sea turtles in situ based upon previously tested techniques for reef fishes. This revealed that through calibration, the curved carapace length (CCL) of marine turtles can be consistently estimated to within 10 cm of their actual size. Although rudimentary, this has advantages for assessing the residency or absence of specific life history stages from particular environments. Indeed, our data supported previous claims that following the reproductive season, adult hawksbills in the region may move away from the nesting beaches to alternative foraging grounds whilst immature turtles (following the pelagic juvenile stage) may opt to reside in areas close to their natal beaches. With regards to habitat utilization, juvenile hawksbills displayed an alternating pattern of short, shallow foraging dives followed by deeper, longer resting dives. These findings are consistent with previous electronic studies of free-range diving in this species and suggest that the maximization of resting duration may be an important factor driving this behaviour.

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Aspectos da ecologia da capivara (Hydrochoerus hydrochaeris) foram estudados na Reserva Biológica do Lami, Rio Grande do Sul, Brasil, de janeiro de 2000 a maio de 2002. A área abrange 210,3 ha, onde são encontrados seis categorias de vegetação (matas, campos úmidos, campos arenosos, banhados arbustivos, banhados herbáceos e juncais) em interface com corpos hídricos (arroio Lami e lago Guaíba). O clima da região é subtropical úmido sem estação seca, com temperatura média anual de 18°C. Foram realizadas contagens diretas dos indivíduos, com identificação de classes etárias, ao longo de transecções fixas que percorriam as cinco categorias de hábitat mais expressivas (excluindo o juncal), totalizando 7.245 m de extensão. Acada indivíduo contactado, registravase a posição espacial e o hábitat em que se encontrava, para identificação dos padrões de uso do espaço e dos hábitats A densidade foi calculada para cada ano de estudo, considerando o maior número de capivaras registrado, resultando em uma densidade de adultos de 0,24 ind/ha em 2000 e 0,21 ind/ha em 2001 e 2002, enquanto que a densidade geral foi de 0,28 ind/ha em 2000, 0,24 ind/ha em 2001 e 0,33 ind/ha em 2002. A proporção de adultos foi, em média, de 67 a 98% da população. O maior número de nascimentos foi registrado no período de primavera/verão. A abundância relativa, em número de indivíduos registrados por quilômetro percorrido, diferiu significativamente entre quatro zonas da área de estudo. Os hábitats mais utilizados foram a mata, o campo úmido e o banhado arbustivo, sendo que, de forma geral, o primeiro foi positivamente selecionado, o segundo apresentou seleção positiva a neutra, e o terceiro foi negativamente selecionado. Não foi verificado um padrão sazonal de uso dos hábitats. Foram registradas, adicionalmente, informações sobre comportamento, interações com aves e causas de mortalidade.