1,724,436 research outputs found
Socio-demographic information for included participants (n = 5248).
No full text<p>Socio-demographic information for included participants (n = 5248).</p
Block Card 5248 Suder Avenue
No full textThis image was produced by the Auditor's Office in Lucas County, Ohio for tax assessment purposes. Associated dates are approximate. Descriptive terms related to this photograph include: dwelling | 5248 Suder Avenue (Toledo, Ohio) | Cape Cod Style | Greenwich Village (Toledo, Ohio) | Point Place (Toledo, Ohio) | North Toledo (Toledo, Ohio
The Extended Bar and Grand-Design Spirals in NGC 5248
Get PDFWe present a study of the grand-design spiral galaxy NGC 5248 (Jogee et al. 2002a, b) based on a combination of multi-wavelength observations and hydro-dynamical modeling. A deep R-band image reveals that what was previously thought to be an inclined disk is in fact an extended bar, embedded within a fainter, more circular, outer disk. NGC 5248 thus provides a classic demonstration of how an extended large-scale stellar bar embedded within a faint outer disk can be missed in imaging studies which lack the sensitivity to detect the outer disk. This effect may well lead high redshift studies to underestimate the fraction of barred galaxies. While bright grand-design spiral arms often stem from the end of a stellar bar, NGC 5248 illustrates that such arms can also result from the gas response and star formation induced on the leading edge of an extended, moderately strong stellar bar. NGC 5248 shows spectacular dust, gas, and stellar grand-design spiral arms which exist on scales of tens of parsecs to tens of kiloparsecs, and connect to a kiloparsec-size starburst ring of bright super star clusters. We illustrate how coupled dynamical mechanisms generate such continuous spiral structures deep inside a barred potential, drive disk evolution,and fuel star formation on progressively smaller scales
Circumnuclear kinematics in NGC 5248: The origin of nuclear spiral arms
No full textWe present for the first time a two-dimensional velocity field of the central region of the grand-design spiral galaxy NGC 5248, at 0.9-arcsec spatial resolution. The Hα velocity field is dominated by circular rotation. While no systematic streaming motions are seen in the area of the nuclear grand-design spiral or the circumnuclear ring, the amplitude of residual velocities, after subtracting a model circular velocity field, reaches 20kms-1 in projection. The rotation curve levels out at around 140 kms -1, after a well-resolved and rather shallow rise. We have generated an analytical model for the nuclear spiral and fitted it to our observations to obtain estimates of the pattern speed of the spiral and the speed of sound in the central region of NGC 5248. Our results are consistent with a low pattern speed, suggesting that the nuclear spiral rotates with the same rate as the main spiral structure in NGC 5248, and thus that the spiral structure is coupled from scales of a few hundred parsecs to several kiloparsecs. We have also compared the observed structure and kinematics between the nuclear regions of NGC 5248 and M100. Several similarities and differences are discussed, including the location of the peak emission regions on major and minor axes, and the spiral arm streaming motions. We find no kinematic evidence for the presence of a nuclear bar in NGC 5248
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
Discovery and implications of a new large-scale stellar bar in NGC 5248
No full textFor decades, the grand-design SAB spiral galaxy NGC 5248 has been postulated to host a short bar of semimajor axis 22" (1.6 kpc). From dynamical and morphological arguments, however, we argue that its spiral structure is being driven by a large- scale bar whose corotation radius lies at similar to115" (8.6 kpc). Our estimate is based partially on a deep R-band image, which reveals that the feature previously thought to be an inclined disk is in fact an extended stellar bar. The bar is embedded within a fainter outer disk visible out to a radius of 230" (17.2 kpc). The bar has a deprojected ellipticity of 0.44 and a semimajor axis of 95" (7.1 kpc). The classical grand- design spirals of NGC 5248, prominent in B, R, and K light, lie on the leading edge of the large-scale stellar bar and are accompanied by concave dust lanes out to at least 70". The offset between the dust and young stars is consistent with our understanding of gas flows in barred galaxies, where shocks along the leading edges of a moderately strong bar compress the gas to form massive young stars. While in many strongly barred galaxies, optical spiral arms are prominent outside the bar but not within it, NGC 5248 illustrates how intense star formation along a moderately strong bar can lead to conspicuous open spiral arms within the bar itself. NGC 5248 also provides a clear example of how a large-scale stellar bar embedded within a faint outer optical disk can be misidentified as an inclined disk when imaging studies lack the sensitivity to detect the actual outer disk. We discuss the implications for the estimated bar fraction at higher redshifts
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
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