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Palaeoenvironmental reconstruction based on charophytes andsedimentology: Can the mid-Holocene Optimum be recognised inwestern Argentina?
No full textWe sought to recognise to which extent the mid-Holocene Optimum can be identified in the Río Jarilla region of western Argentina, situated at the boundaries of the South American Arid Diagonal. The palaeoenvironmental conditions of the Arco del Desaguadero Formation, formed by a sedimentary sequence of late Pleistocene to middle Holocene age, were reconstructed based on charophyte assemblages and sedimentology. Three fluvio-lacustrine cycles were recognised with evaporitic layers at the top of each, reflecting the high temperatures that characterise the Holocene. For the second cycle, three 14C dates were obtained, ranging from ca. 11 to 7 ka BP which, together with sedimentology and the palaeontological record allowed us to infer a warm and semiarid period assigned to the mid-Holocene Climatic Optimum. The gyrogonites found in the sediments belong to Chara cf. contraria, Chara cf. papillosa, Chara halina and Chara hornemannii, species related to extant species from Argentina. The presence of C. hornemannii imbedded in sedimentary rocks (evaporites) reflects higher temperatures in the past, although further research is needed to establish the significance of this species for reconstructing Quaternary climate.Fil: Font, Eimi Ailen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico San Luis; ArgentinaFil: Chiesa, Jorge O.. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geologia; Argentin
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
Biostratigraphy of the Pliocene and Pleistocene from center-west of San Luis, Argentina
Get PDFSe presentan evidencias sedimentológicas y paleobiológicas del Cenozoico superioraflorantes al sur del Alto Pencoso (Serranías Occidentales), correspondientes a las cuencas:noroeste de Beazley, valle del río Desaguadero y Salina del Bebedero. En Beazley aflora laFormación Las Mulitas (fluvial, Plioceno), caracterizada por los restos fósiles de Notoungulatay Dasypodidae y cubierta por las formaciones Toro Muerto (aluvial, Pleistoceno medio), AltoGrande (fluvial, Pleistoceno tardío) y Barranquita (eólico, Pleistoceno tardío). Esta última conregistros paleontológicos asignados a Glyptodontidae y Macraucheniidae. En la base del arro-yo Jarilla aflora la Formación Arco del Desaguadero (fluvial, Pleistoceno tardío) en la que sereconocieron girogonitos de Chara contraria, C. cf. Papillosa y C. hornemannii. Asimismo, enlos depósitos costeros de la Salina del Bebedero (fluvio-lacustre, Pleistoceno tardío) se iden-tificaron las conchillas de Chilina mendozana, Heleobia parchappii, Biomphalaria peregrina ylas valvas de Sphaeriidae. Las sedimentitas cretácicas de las Serranías Occidentales fueronla principal área de aporte sedimentario durante el Neógeno, rellenando las depresiones tec-tónicas circundantes, con depósitos de planicies aluviales y sistemas fluviales que caracterizanla cuenca de Beazley. Finalmente, las condiciones climáticas globales vinculadas a la últimaglaciación en la región cordillerana andina, se manifiestan en los depósitos fluviales arenososde la cuenca del río Desaguadero, las gravas arenosas calcáreas costeras de la laguna delBebedero y las arenas y limos eólicos que cubren parcialmente la planicie circundanteThis contribution reports sedimentological and paleobiological evidences from the upper Cenozoic outcrops in the south of Alto Pencoso (Occidental Ranges). They belong to: the Norwest Beazley, Desaguadero’s river valley and Salina del Bebedero basins. Las Mulitas Formation crops out in Beazley (fluvial, Pliocene) and is characterized by the fossils remains of Notoungulata y Dasypodidae, and is covered by Toro Muer to (alluvial, middle Pleistocene), Alto Grande (fluvial, late Pleistocene) and Barranquita (eolian, late Pleistocene) formations. The latter with paleontological records assigned to Glyptodontidae and Macraucheniidae. At the river-bed of Jarilla stream crops out the Arco del Desaguadero Formation (fluvial, late Pleistocene), where Chara contraria, C. cf. papillosa and C. hornemannii girogonites were recognized. Likewise, in the foreshore deposits from Salina del Bebedero (fluvio-lacustrine, late Pleistocene) Chilina mendozana, Heleobia parchappii, Biomphalaria peregrina and Sphaeriidae shells were identified. The cretacic sedimentary rocks from the Occidental ranges were the main sedimentary source area during the Neogene, filling the tectonic depressions, with alluvial plains and fluvial systems deposits that characterize the Beazley’s basin. Finally, the global climatic conditions related to the Last Glaciation in Los Andes range are represented by the fluvial sandy deposits of the Desaguadero’s river basin, the foreshore gravel sandy and calcareous deposits from the Bebedero lake and the eolian sand and silt deposits that partially covers the surrounding plain.Fil: Font, Eimi Ailen. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; ArgentinaFil: Chiesa, Jorge Orlando. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; ArgentinaFil: Lucero, Natalia Paola. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Luis; Argentina. Universidad Nacional de San Luis. Facultad de Ciencias Físico Matemáticas y Naturales. Departamento de Geología; Argentin
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
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
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