1,720,959 research outputs found
Um Eqüídeo Fóssil do Pleistoceno de Alegrete, RS, Brasil
Get PDFFossil mammals and reptiles were found at the basal conglomeratic level from the Salatiel II outcrop, Sanga da Cruz, Alegrete, Rio Grande do Sul, which gave an approximate thermoluminescence age of 14.000 years BP (before present). The fossil herein studied consists of a left dentary fragment of a horse, identified from the occlusal teeth surface as Hippidion cf. Hippidion principale. A preliminary analysis of the associated fauna permits to achieve some paleoclimate inferences for the region, presumably colder than the present
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Paleoalterações e Carbonatos em Depósitos Aluviais na Região de Santa Maria, Triássico Médio a Superior do Sul do Brasil
Get PDFFive types of paleo-weathering and carbonate precipitation were recognized in fine-grained deposits of the Alemoa Member, Santa Maria Formation, Middle to Upper Triassic of southern Brazil. The fauna and flora found in these lithologies are important dating tools, but only in a generic way, misleading the time involved in periods of deposition and non deposition. The identified types of deposits are (i) reddish mudstones, with none or little paleo-weathering, (ii) mottled mudstones, with incipient pedogenesis, mainly mottling, destratification, animal and vegetal colonization, (iii) carbonate veins, with more evidences of exposure and root action, (iv) carbonate siltstones/sandstones, where restricted fluvial deposits are cemented by phreatic carbonate, and (v) carbonate nodules and lenses, in which small lenses of a very compact calcrete are at the top and in the center of carbonated siltstone/sandstone beds, distinguished by its crystalinity, hardness and brighter color. The recorded microfacies point to a cyclic variation of the mainly high phreatic level, forming cracks and pedotubules (pedogenesis) filled with carbonate and Fe and Mn oxides (phreatic). The identification of five distinct pedofacies and the stratigraphic correlation in the sedimentary package of the Alemoa Member (base, middle or topmost position) suggest a probable association of paleo-weathering processes and vertebrate preservation. Near channel facies, mainly at the base and top, present smaller exposure periods and higher variations on the phreatic level, and consequently, the best preserved vertebrate fossils. On the other hand, facies which are far from the channel, record more subaerial exposure and more significant phreatic variation, leading to more advanced (although still incipient) paleo-weathering and carbonate precipitation, and to a worst fossil preservation
Dinossaurinho ou Dinossaurão? Investigação da variação intraespecífica nos primeiros dinossauros não-avianos conhecidos
No full textIntroduction. Intraspecific variation refers to the morphological or behavioral differences observed among individuals of the same species, determined by various factors such as ontogenetic changes, sexual dimorphism, individual variation, and pathological conditions caused by diseases or injuries. Objective. This study briefly presents the main factors that generate intraspecific variation in early dinosaurs, as well as the methods used to analyze it (e.g., investigation of external morphology, morphometrics, histology). Methodology. The investigation involved a systematic review of the specialized literature. Results. In the field of Paleontology, studies indicate that the failure to recognize this type of intraspecific variation may be a factor responsible for instability in phylogenetic inferences related to dinosaurs. Conclusion. It is emphasized that detailing intraspecific variation in dinosaurs requires an adequate number of individuals with variability in size, shape, and bone deposition. However, there is a promising outlook for this field of study, as different research groups have been making efforts toward the discovery of new materials.Introducción. La variación intraespecífica se refiere a las diferencias morfológicas o comportamentales observadas entre individuos de una misma especie, determinadas por diversos factores como cambios ontogenéticos, dimorfismo sexual, variación individual y condiciones patológicas debido a enfermedades o lesiones. Objetivo. El presente estudio presenta, de manera breve, los principales factores que generan la variación intraespecífica en los primeros dinosaurios, así como los métodos para analizarla (por ejemplo, investigación de la morfología externa, morfometría, histología). Metodología. La investigación consistió en una revisión sistemática de la literatura especializada. Resultados. En el campo de la Paleontología, los estudios indican que no reconocer este tipo de variación intraespecífica puede ser un factor responsable de la inestabilidad en las inferencias filogenéticas relacionadas con los dinosaurios. Conclusión. Se destaca que el análisis detallado de la variación intraespecífica en dinosaurios requiere un número adecuado de individuos con cierta variabilidad en su tamaño, forma y deposición ósea. No obstante, el panorama para este campo de estudio es prometedor, ya que diferentes grupos de investigación han estado dedicando esfuerzos al descubrimiento de nuevos materiales.Introdução. A variação intraespecífica refere-se às diferenças morfológicas ou comportamentais observadas entre indivíduos de uma mesma espécie, sendo determinadas por diversos fatores, como mudanças ontogenéticas; dimorfismo sexual; variação individual e condições patológicas devido a doenças ou lesões. Objetivo. O presente estudo apresenta, de forma breve, os principais fatores que geram a variação intraespecífica nos primeiros dinossauros, bem como os meios de analisá-la (e.g., investigação da morfologia externa, morfometria, histologia). Metodologia. A investigação envolveu uma revisão sistemática da literatura especializada. Resultados. No campo da Paleontologia, estudos indicam que a falha em reconhecer esse tipo de variação intraespecífica pode ser um fator responsável pela instabilidade nas inferências filogenéticas relacionadas aos dinossauros. Conclusão. Ressalta-se que o detalhamento da variação intraespecífica em dinossauros necessita de um número adequado de indivíduos com certa variabilidade no seu tamanho, forma e deposição óssea, mas há um cenário promissor para esse campo de estudos, uma vez que diferentes grupos de pesquisa têm dedicado esforços tanto à descoberta de novos materiais
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