986 resultados para 151-912
Resumo:
A novel and promising biomarker proxy for reconstruction of Arctic sea ice conditions was developed and is based on the determination of a highly branched isoprenoid with 25 carbons (IP25). IP25 records have been restricted to the last 150 kyr BP. We present a biomarker record from Ocean Drilling Program (ODP) Site 912, going back to the Pliocene-Pleistocene boundary and indicating that sea ice of variable extent occurred in the Fram Strait/southern Yermak Plateau area at least since about 2.2 Ma. Furthermore, our data support the idea that a combination of IP25 and open water, phytoplankton biomarker data ("PIP25 index") may give a more reliable and quantitative estimate of past sea ice cover (at least for the study area). The study reveals that the novel IP25/PIP25 biomarker approach has potential for semi-quantitative paleo-sea ice studies covering the entire Quaternary and could motivate further detailed high resolution research on ODP/IODP material using this proxy.
Resumo:
Contenido: Aspectos fundamentales del conocimiento humano. 1. El conocimiento sensitivo / Octavio N. Derisi -- Filosofía griega y cristianismo según W. Jaeger / Cesáreo López Salgado -- La analogía en el concepto de ciencia aristotélico-tomista / William R. Darós -- Pasión e instinto en B. Pascal / Francisco Leocata -- Notas y comentarios -- Bibliografía
Resumo:
Analisa as repercussões sociais e os sucedâneos jurídicos à falta de regulamentação em lei de usos e costumes, já incorporados ao "modus vivendi" da sociedade, de populações de orientação minoritária. Descreve e analisa os debates travados em torno do Projeto de Lei nº 1.151/1995 que trata da união civil homossexual e da criação do instrumento legal intitulado parceria civil registrada.
Resumo:
Estudo de caso sobre o Projeto de Lei n. 1.151/1995, de autoria da deputada Marta Suplicy, que trata da união civil entre pessoas do mesmo sexo.
Resumo:
The purpose of this work is a contribution to the quantitative record of the use of iron by planktonic algae. Preliminary experiments with Chlorella to determine the rate of iron intake in the presence of inorganic sources of iron did not produce the desired result. The crucial point of this work is the investigation of the influence of various external factors on the stability of FeEDTA (FeEDTA = Ferric(III)-compound of ethylene-diamine tetra-acetic acid), since this compound appears to be particularly well-suited as a source of iron for planktonic algae (e.g. TAMIYA et al. 1953). Cultures of Chlorella fusca in a light thermostat were used in experimental research. Methods and results are discussed.
Resumo:
Eudiaptomus vulgaris Schmeil is the most abundant copepod in Lake Maggiore and forms also, in respect to other entomostraca, the most important element, through its average biomass and because it is fairly numerous throughout the year. Plankton samples collected in a systematic and quantitative way, gave the opportunity to study some aspects of the dynamics of the population of this copepod, in safety in view of the uncertainty which in this kind of study can ensue when samples are taken only at a single station - in consequence of the changes in size of population between different water masses. The results of the biometrical observations are of the population of Eudiaptomus vulgaris is presented.