1,720,957 research outputs found
Recent boulder falls within the Finsen crater on the lunar far side: An assessment of the possible triggering rationale
No full textTo better understand the necessary triggers for the origin of the lunar boulder tracks, we report 650 tracks from the ~73 km in diameter Finsen crater. The tracks
were identified on the crater wall and the central peak region of the Finsen crater, located within the South Pole ̶ Aitken basin on the lunar far side. In this manuscript,
we assessed two main possibilities of triggers, 1) ground shakings by the recent meteorite impact, and 2) ground shaking from recent fault reactivation associated
with the lobate scarps identified inside and in the vicinity of the Finsen crater. Our assessments revealed that the impact-induced seismicity could have generated the
moonquake with the maximum moment magnitude (MW) 4.63. We also estimated that the moonquakes excited by the movements along the lobate scarps had an
estimated cumulative (or maximum possible) moment magnitude (MW) up to 6.86 and 6.90, i.e., for the basaltic and noritic basement respectively. Considering the
location of the Finsen crater positioned over the structural discontinuity along the boundary of the central and mid rings of the South Pole ̶ Aitken basin and higher
moment magnitude generated from the fault movements, we propose that the region is potentially seismotectonically active, and reactivation of pre-existing faults
possibly triggered/triggers the necessary ground motion for the boulders to initiate their movements. However, impact-induced ground shakings and deep-focused
moonquakes also remain possibilities for triggers
Tectonism of late Noachian Mars: Surface signatures from the southern highlands
Full text linkUpwelling mantle plumes often instigate extensional stress within the continental crust of
Earth. When stress exceeds crustal strength, extensional structures develop, reducing the effective
stress and trigger magmatic processes at the crust–mantle boundary. However, such processes and
their relationship to the formation of many surface structures remain poorly characterized on Mars.
We identified a series of extensional structures in the southern highlands of Mars which collectively
resemble continental rift zones on Earth. We further characterized these extensional structures and
their surrounding region (area of ~1.8 M km2) by determining the surface mineralogy and bulk regional geochemistry of the terrain. In turn, this constrains their formation and yields a framework
for their comparison with extensional structures on Earth. These terrains are notable for olivine and
high-Ca pyroxene with a high abundance of potassium and calcium akin to alkali basalts. In the case
of Mars, this Earth-like proto-plate tectonic scenario may be related to the plume-induced crustal
stretching and considering their distribution and temporal relationship with the Hellas basin, we
conclude that the plume is impact-induced. Overall, the findings of this work support the presence
of mantle plume activity in the Noachian, as suggested by thermal evolution models of Mars
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Full text linkWe 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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