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Greater socio-environmental instability favors the individual production of knowledge because innovations are adapted to new circumstances. Furthermore, instability stimulates the horizontal transmission of knowledge because this mechanism disseminates adapted information. This study investigates the following hypothesis: Greater socio-environmental instability favors the production of knowledge (innovation) to adapt to new situations, and socio-environmental instability stimulates the horizontal transmission of knowledge, which is a mechanism that diffuses adapted information. In addition, the present study describes “how”, “when”, “from whom” and the “stimulus/context”, in which knowledge regarding medicinal plants is gained or transferred. Data were collected through semi-structured interviews from three groups that represented different levels of socio-environmental instability. Socio-environmental instability did not favor individual knowledge production or any cultural transmission modes, including vertical to horizontal, despite increasing the frequency of horizontal pathways. Vertical transmission was the most important knowledge transmission strategy in all of the groups in which mothers were the most common models (knowledge sources). Significantly, childhood was the most important learning stage, although learning also occurred throughout life. Direct teaching using language was notable as a knowledge transmission strategy. Illness was the main stimulus that triggered local learning. Learning modes about medicinal plants were influenced by the knowledge itself, particularly the dynamic uses of therapeutic resources.  相似文献   
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In this article, we present the Brazilian Portuguese Lexicon, a new word-based corpus for psycholinguistic and computational linguistic research in Brazilian Portuguese. We describe the corpus development, the specific characteristics on the internet site and database for user access. We also perform distributional analyses of the corpus and comparisons to other current databases. Our main objective was to provide a large, reliable, and useful word-based corpus with a dynamic, easy-to-use, and intuitive interface with free internet access for word and word-criteria searches. We used the Núcleo Interinstitucional de Linguística Computacional’s corpus as the basic data source and developed the Brazilian Portuguese Lexicon by deriving and adding metalinguistic and psycholinguistic information about Brazilian Portuguese words. We obtained a final corpus with more than 30 million word tokens, 215 thousand word types and 25 categories of information about each word. This corpus was made available on the internet via a free-access site with two search engines: a simple search and a complex search. The simple engine basically searches for a list of words, while the complex engine accepts all types of criteria in the corpus categories. The output result presents all entries found in the corpus with the criteria specified in the input search and can be downloaded as a.csv file. We created a module in the results that delivers basic statistics about each search. The Brazilian Portuguese Lexicon also provides a pseudoword engine and specific tools for linguistic and statistical analysis. Therefore, the Brazilian Portuguese Lexicon is a convenient instrument for stimulus search, selection, control, and manipulation in psycholinguistic experiments, as also it is a powerful database for computational linguistics research and language modeling related to lexicon distribution, functioning, and behavior.  相似文献   
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Systematic Parasitology - A new parasitic copepod, Ergasilus yandemontei n. sp., is described based on 10 adult females collected from the gills of the atherinid silverside Odontesthes hatcheri...  相似文献   
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We present a phylogenetic analysis of the New World dipsadids based on an expanded data matrix that includes 246 terminal taxa including 196 dipsadids. The species are sampled for eight genes (12S, 16S, cytb, nd2, nd4, bdnf, c‐mos, rag2). The data are explored using two distinct optimality procedures—maximum parsimony and maximum likelihood—and two alignment strategies—dynamic homology and static homology. Two previously unsampled dipsadid genera, Sordellina and Rhachidelus, are now included in the analysis. The definitions of the genera, Erythrolamprus, Clelia, Hypsirhynchus, Philodryas and Phimophis, and the tribes Alsophiini, Echinantherini and Conophiini, are revised. In order to maintain monophyly, the genus Umbrivaga is synonymized with Erythrolamprus, and two new genera are erected to accommodate Phimophis iglesiasi and Clelia rustica, as well as their closely related species. The West Indian genera Schwartzophis, Darlingtonia, Antillophis and Ocyophis are resurrected. © The Willi Hennig Society 2012.  相似文献   
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