1,721,782 research outputs found
Petrology and Geochemistry of New Paired Martian Meteorites LAR 12240 and LAR 12095
No full textThis project describes two Martian meteorites, paired olivine-phyric shergottites LAR 12240 and LAR 12095, in order to decipher their petrological context, and place constraints on the geological history of Mars. This project identifies all phases found in LAR 12240 and 12095 and analyzes them for major and trace elements. The textural relationships among these phases are examined in order to develop a crystallization history of the magma(s) that formed these basalts. Two polished, 100 µm thick sections of the paired Martian meteorites LAR 12240 and LAR 12095 were obtained for the purpose of this study. A petrographic microscope, a JEOL JXA 7600F scanning electron microscope (SEM), a Cameca SX100 Electron microprobe (EMP) and a laser ablation inductively coupled plasma mass spectrometer (LA-ICP-MS) were used to complete this study. LAR 12095 and LAR 12240 are typical olivine-phyric shergottites with Mg-rich olivine megacrysts in a groundmass comprised of pyroxene, smaller Fe-rich olivines and interstitial plagioclase. The olivine megacrysts are likely antecrysts and contain numerous melt inclusions that are more evolved than the bulk-rock compositions of LAR 12095 and LAR 12240 or compositions of shergottite parent magmas from the literature. The crystallization of LAR 12240 and LAR 12095 likely began with the crystallization of Cr-rich spinels (T1) and the Mg-rich olivine megacryst cores followed by progressively less Cr-spinels (T2 and T3) crystallizing along with the outer edges of the olivine megacrysts and pigeonite. The olivine megacrysts were then entrained in a magma that crystallized at or near the Martian surface. The magma would have begun crystallizing more T2 and T3 along with 0.5-1 mm and 0.1 mm sized Fo60 olivines and the last of the pigeonite followed by augite, plagioclase feldspar, ulvöspinel (T4 and T5) sulfides and merrillite. These meteorites have calculated fo2 values range from ΔFMQ of -3.7 to -1.7 and depleted (light rare earth element) LREE patterns which place them into the reduced, depleted shergottite group. LAR 12095 and LAR 12240 most closely resemble SaU 005 for their major and trace element compositions. These meteorites also closely resemble DaG 489 for trace element compositions.Earth and Atmospheric Sciences, Department o
Petrology and Geochemistry of New Paired Martian Meteorites Larkman Nunatak 12240 and Larkman Nunatak 12095
Get PDFTwo of the latest Martian meteorites found in Antarctica, paired olivine-phyric shergottites LAR 12240 and LAR 12095, are described in order to decipher their petrological context, and place constraints on the geological history of Mars. This project identifies all phases found in LAR 12240 and 12095 and analyzes them for major and trace elements. The textural relationships among these phases are examined in order to develop a crystallization history of the magma(s) that formed these basalts
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
Peology and Geochemistry of New Paired Martian Meteorites 12095 and LAR 12240
Get PDFThe meteorites LAR 12095 and LAR 12240 are believed to be paired Martian meteorites and were discovered during the Antarctic Search for Meteorites (ANSMET) 2012-2013 Season at Larkman Nunatak. The purpose of this study is to characterize these olivine-phyric shergottites by analyzing all mineral phases for major, minor and trace elements and examining their textural relationships. The goal is to constrain their crystallization history and place these shergottites among other Martian meteorites in order to better understand Martian geological history
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
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