1,129 research outputs found
Species differences in the songs of the critically endangered Niceforo\u27s Wren and the related Rufous-and-white Wren
Niceforo\u27s Wrens (Thryothorus nicefori) and Rufous-and-white Wrens (Thryothorus rufalbus) are closely related Neotropical birds. Niceforo\u27s Wrens, critically endangered endemic Colombian songbirds, are generally considered a sister species to Rufous-and-white Wrens, although some have suggested that they may represent a well-marked race. A careful comparison of the two taxa has never been conducted. Here we present a thorough study of the songs of male Niceforo\u27s and Rufous-and-white Wrens based on recordings collected throughout both species\u27 geographic ranges. Both species sing low-pitched songs composed of varied pure tone whistles. Niceforo\u27s Wren songs are shorter and simpler with fewer syllables and syllable types; they have higher frequency trills and terminal syllables; and they have distinctive terminal syllables with a broader bandwidth, higher frequency of maximum amplitude, and a larger number of frequency modulations. Discriminant analysis based on fine structural details of songs differentiates the two species. In a subspecies-level discriminant analysis, all five subspecies of Rufous-and-white Wren cluster together and are distinct from Niceforo\u27s Wren. Comparisons of morphometric measurements and plumage features reveal parallel differences in body size (Niceforo\u27s Wrens are larger for most measurements) and plumage color (Niceforo\u27s Wrens are more gray than Rufous-and-white Wrens). This study is the first to compare Rufous-and-white versus Niceforo\u27s Wrens with a quantitative approach and supports the idea that these taxa are best understood as distinct species. © The Cooper Ornithological Society 2007
Vocal behavior of the critically endangered Niceforo\u27s Wren (Thryothorus nicefori)
Niceforo\u27s Wren (Thryothorus nicefori) is a critically endangered songbird endemic to dry forests of the Chicamocha Valley in central Colombia. Discovered in 1946 and red-listed by the IUCN since 1988, Niceforo\u27s Wren faces a threat of extinction because of its limited habitat range and increasing deforestation for agriculture and livestock. This species has been poorly studied, and its vocal behavior is yet undescribed. We provide the first description of the vocalizations of Niceforo\u27s Wren, based on analyses of recordings from 29 individuals (more than half of all estimated living individuals of this species). We examined the fine structure of their songs, the pattern of solo and duet singing behavior, and the song repertoire size of males and females. Both sexes produce solo songs, coordinated vocal duets, and a variety of calls. Songs have a stereotyped syntax including one or more introductory syllables, a trill of rapidly repeated syllables, and a frequency-modulated terminal syllable. Males have a repertoire of at least 12-21 different song types, whereas females have a repertoire of at least 7-9. Both sexes sing solo songs with eventual variety. Male songs are more complex and have lower frequency characteristics, whereas female songs are shorter, with fewer syllable types and fewer syllable repeats. Duets involve mated pairs singing in a coordinated fashion using the same song types from their solo repertoires. Duets typically begin with a male song followed by a female song and show variable levels of complexity involving one to two songs given by each individual. Our results provide a foundation for monitoring Niceforo\u27s Wrens and facilitating conservation of this critically endangered species. © The American Ornithologists\u27 Union, 2008
Nervio terminal: el par craneal cero
Resumenbn múlíáéles íexíos se afárma que exásíen solameníe doce éares de nervios craneales. Estos omiten la existencia de otro par craneal, el nervio terminal o par craneal cero. Este trabajo retoma dicho nervio como éar cranealI eséecáfácando sus conexáones ó su éaéel funcáonalen la migración de neuronas liberadoras de la hormona gonadotróéáca EdnoeFK pe élaníea la háéóíesás de la exásíencáa fálogenéíáca de un sector cerebral y de un nervio común, que integra el nervio íermánal con los nerváos olfaíoráos ó los nerváos vómeroJnasalesal éarecer cuméláendo la funcáón de deíeccáón de olores ó de la oráeníacáón en la búsqueda de alámeníosI deíeccáón de feromonas y regulación vascular nasal.[Duque JE, Duque CA. Nervio terminal: el par craneal cero. MedUNAB 2006; 9:246-249].Palabras clave: Nervio terminal, par craneal cero, hormona gonadotrópica, síndrome de Kallmann
Pedagogía y educación virtual en un programa de extensión rural
El presente artículo se deriva de los resultados del proyecto “Diseño y evaluación de un programa de capacitación a capacitadores para la educación rural vía Internet”, que tuvo como propósito buscar modelos alternativos de extensión universitaria en los que la pedagogía promueva el desarrollo de competencias profesionales. Se examina la Internet como instrumento que posibilita superar condiciones de tiempo y lugar que limitan la educación continuada de profesionales y técnicos en provincia, así como el acompañamiento de la Universidad a procesos locales. Como resultado principal se concluye que la propuesta pedagógica debe superar las posibilidades y limitaciones de la tecnología mediadora, así como focalizar las necesidades de los actores y los fines del proceso educativo. Un nuevo modelo de enseñanza-aprendizaje virtual exige, tanto a docentes como a discentes, ajustes en la forma de relacionarse y participar en dicho proceso. En este contexto, el profesor no sólo trasmite, sino que debe entrar en diálogo, guiar, motivar y facilitar que el alumno asuma una posición analítica, crítica, comprensiva e interpretativa de la teoría y la realidad; para el estudiante es indispensable la motivación y la disciplina. En atención a la ‘soledad’ del estudiante a distancia, el relacionamiento que se debe dar en el modelo virtual ha ser más dinámico. Se enfatiza que la virtualidad es un medio que facilita el establecimiento de nuevas relaciones sociales que fortalecen las relaciones universidad-región, no sólo para suplir la presencialidad, sino para dar mayor continuidad y calidad a los procesos educativos
Unconventional Raw Natural Sustainable Sources for Obtaining Pharmacological Principles Potentially Active on CNS Through Catalytic, Ecologically Clean, Processes
Using machine learning and information visualisation for discovering latent topics in Twitter news
We propose a method to discover latent topics and visualise large collections
of tweets for easy identification and interpretation of topics, and exemplify
its use with tweets from a Colombian mass media giant in the period 2014--2019.
The latent topic analysis is performed in two ways: with the training of a
Latent Dirichlet Allocation model, and with the combination of the FastText
unsupervised model to represent tweets as vectors and the implementation of
K-means clustering to group tweets into topics. Using a classification task, we
found that people respond differently according to the various news topics. The
classification tasks consists of the following: given a reply to a news tweet,
we train a supervised algorithm to predict the topic of the news tweet solely
from the reply. Furthermore, we show how the Colombian peace treaty has had a
profound impact on the Colombian society, as it is the topic in which most
people engage to show their opinions.Comment: 10 pages, 6 figures, to be presented at SmartTech-IC 201
O DIREITO A SER ESQUECIDO OU DIREITO AO ESQUECIMENTO NO DIREITO DIGITAL BRASILEIRO
Sendo a sociedade técnica aquela que procura em quaisquer de suas atuações, dentre todos os meios, o mais eficaz, pode-se afirmar que o acesso à informação é demasiadamente acelerado e difundido no meio ambiente digital, pois este é o meio mais eficaz para a divulgação e propagação de informações. Nesse contexto técnico e informacional, o presente artigo objetiva defender a existência e aplicabilidade do direito a ser esquecido ou o direito ao esquecimento no direito digital brasileiro, a partir dos fundamentos do caso Google vs AEPD e Mario Costeja González, bem como do Marco Civil da Internet (Lei n. 12.965/2014), do estudo da Lei Geral de Proteção de Dados (Lei n. 13.709/2018) e dos fundamentos constitucionais presentes no voto minoritário do Ministro Edson Fachin no julgamento do Recurso Extraordinário 1.010.606/RJ. Para tanto, considera-se que não há direito fundamental absoluto e que na análise casuística devem ser ponderados os núcleos essenciais a serem protegidos, de modo a promover a harmonia dos valores consagrados em nosso ordenamento. A pesquisa, notadamente bibliográfica e jurisprudencial, seguiu, quanto ao método de abordagem, a dedução, para a análise das referências de doutrinas e legislações utilizadas, e a indução para analisar os casos já julgados sobre direito ao esquecimento, seja no âmbito interno brasileiro, pelo STJ e pelo STF, ou na órbita externa pelos tribunais internacionais. Como conclusão parcial assevera-se que, apesar da possibilidade de o direito não se efetivar em um determinado contexto, a pretensão de ser esquecido ou ao esquecimento encontra respaldo em nosso ordenamento jurídico, inclusive para o âmbito digital (desindexação)
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