50 research outputs found

    Sound production mechanism in the semiterrestrial crab Neohelice granulata (Brachyura, Varunidae)

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    Very few studies of sound production in the Brachyura have simultaneously identified the type of individuals (e.g. sex) producing acoustic signals, the structures involved in making sound and the social context. The emission and type of sound signals in Neohelice granulata were previously characterized, but the sex and the body structures involved in the sound production mechanism were not determined. In the present study, experiments conducted in the laboratory demonstrated that acoustic signals were produced by males through an up-down movement of the cheliped by rubbing the merus against the pterygostomial area of the carapace. The micromorphology of the merus showed that it has a ridge of tubercles which may act as a plectrum, while the pterygostomial area bears tubercles and might function as the pars stridens. Acoustic signals were displayed more frequently in the presence of receptive females. Agonistic encounters among males also occurred more often in the presence of receptive females. We propose that Neohelice granulata males use their chelipeds to produce sound signals in a mating context, probably to attract the receptive female and/or to repel other males when a receptive female is present. Thus, the display might have a reproductive function influencing mate choice.Fil: Sal Moyano, María Paz. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; ArgentinaFil: Ceraulo, Maria. Consiglio Nazionale delle Ricerche; ItaliaFil: Mazzola, Salvatore. Consiglio Nazionale delle Ricerche; ItaliaFil: Buscaino, Giuseppa. Consiglio Nazionale delle Ricerche; ItaliaFil: Gavio, Maria Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Mar del Plata. Instituto de Investigaciones Marinas y Costeras. Universidad Nacional de Mar del Plata. Facultad de Ciencias Exactas y Naturales. Instituto de Investigaciones Marinas y Costeras; Argentin

    Multigene analyses resolve early diverging lineages in the Rhodymeniophycidae (Florideophyceae, Rhodophyta).

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    Multigene phylogenetic analyses were directed at resolving the earliest divergences in the red algal subclass Rhodymeniophycidae. The inclusion of key taxa (new to science and/or previously lacking molecular data), additional sequence data (SSU, LSU, EF2, rbcL, COI-5P), and phylogenetic analyses removing the most variable sites (site stripping) have provided resolution for the first time at these deep nodes. The earliest diverging lineage within the subclass was the enigmatic Catenellopsis oligarthra from New Zealand (Catenellopsidaceae), which is here placed in the Catenellopsidales ord. nov. In our analyses Atractophora hypnoides was not allied with the other included Bonnemaisoniales, but resolved as sister to the Peyssonneliales, and is here assigned to Atractophoraceae fam. nov. in the Atractophorales ord. nov. Inclusion of Acrothesaurum gemellifilum gen. et sp. nov. from Tasmania has greatly improved our understanding of the Acrosymphytales, to which we assign three families, the Acrosymphytaceae, Acrothesauraceae fam. nov. and Schimmelmanniaceae fam. nov. This article is protected by copyright. All rights reserved

    Scientific education: issues of researches in partnership

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    This paper describes the results of two studies concerning scientific education. The first one has been developed in a European context over the past decade, while the second one is recent (2008-2009) and concerns a national partnership. Both studies have been carried out according to a constructivist perspective which is widely explained

    Education for health. Rationales, objectives and partnership practices

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    Good quality learning cannot be attained purely through transmissive teaching as learners should be the protagonists in re-organizing their knowledge and in building a new one under the direction of the teacher. Following this approach, it is essential that people link knowledge to action so that they actively work to change or improve their societies at a local level and beyond. According to this point of view, the teacher is considered as a facilitator, who puts the student in problematic situations to favour the elaboration of suitable strategies, poses proper questions to solicit creativity and reflection as well, while in traditional teaching the flow of information and interaction is limited to a one way direction (teacher towards pupils) leading to unsatisfactory results. In this process, a real partnership established involving students, teachers and researchers, will contribute to the professional development of all participants: everybody learns, researchers too, because their cognitive models are better shaped and enforced by practice. In the paper an example of the partnership is described

    Il Progetto SEMEP dell'Unesco compie quindici anni. Le attivit\ue0 italiane.

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    Attivit\ue0 di ricerca nell'ambito di un progetto internazionale promosso dall'Unesco
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