The importance of numax (the frequency of maximum oscillation power) for asteroseismology has been demonstrated widely in the previous decade, especially for red giants. With the large amount of ...photometric data from CoRoT, Kepler and TESS, several automated algorithms to retrieve numax values have been introduced. Most of these algorithms correct the granulation background in the power spectrum by fitting a model and subtracting it before measuring numax. We have developed a method that does not require fitting to the granulation background. Instead, we simply divide the power spectrum by a function of the form nu^-2, to remove the slope due to granulation background, and then smooth to measure numax. This method is fast, simple and avoids degeneracies associated with fitting. The method is able to measure oscillations in 99.9% of previously-studied Kepler red giants, with a systematic offset of 1.5 % in numax values that that we are able to calibrate. On comparing the seismic radii from this work with Gaia, we see similar trends to those observed in previous studies. Additionally, our values of width of the power envelope can clearly identify the dipole mode suppressed stars as a distinct population, hence as a way to detect them. We also applied our method to stars with low (0.19--18.35 muHz) and found it works well to correctly identify the oscillations.
Asteroseismology is well-established in astronomy as the gold standard for
determining precise and accurate fundamental stellar properties like masses,
radii, and ages. Several tools have been ...developed for asteroseismic analyses
but many of them are closed-source and therefore not accessible to the general
astronomy community. Here we present $\texttt{pySYD}$, a Python package for
detecting solar-like oscillations and measuring global asteroseismic
parameters. $\texttt{pySYD}$ was adapted from the IDL-based $\texttt{SYD}$
pipeline, which was extensively used to measure asteroseismic parameters for
$\textit{Kepler}$ stars. $\texttt{pySYD}$ was developed using the same
well-tested methodology and comes with several new improvements to provide
accessible and reproducible results. Well-documented, open-source
asteroseismology software that has been benchmarked against closed-source tools
are critical to ensure the reproducibility of legacy results from the
$\textit{Kepler}$ mission. Moreover, $\texttt{pySYD}$ will also be a promising
tool for the broader astronomy community to analyze current and forthcoming
data from the NASA TESS mission.
The 48th (2017) edition of Les Rencontres de photographie dʼArles offered, amongst its varied and rich programme of some 40 exhibitions, retrospectives of two influential American photographers: Joel ...Meyerowitz: Early Works as the monographic highlight of the main programme of the Rencontres, and Annie Leibovitz: The Early Years, 1970-1983 as an associated programme commissioned and organized by the private LUMA Foundation. It is probably fair to say that the two artists are very different in...
Spinal deformities among captive sand tiger sharks, Carcharias taurus, are unfortunately common, and abnormal swimming behavior due to constrained aquarium space has been hypothesized to contribute ...to the development of this condition. Public aquaria across the United States were surveyed for number, condition (healthy vs. affected), and total length of resident C. taurus specimens and for dimensions of their aquaria. They were also asked to record 10 minute video segments of individual C. taurus swimming in lateral view. Total length of sharks, regardless of condition, averaged 225 ± 5 (mean ± SE) cm. Aquarium shapes varied widely, but aquaria held median volumes of 1.03 X 106 L, and were a median of 4.6 m in depth and 20.7 m in greatest horizontal distance. The greatest horizontal distance of aquaria was negatively correlated with disease prevalence of resident populations in a logarithmic fashion (r = 0.72). Behaviorally, sharks were assessed for total time and percentage of time spent swimming in a specific direction (clockwise, counter-clockwise, or linear), in a glide, and tail-beat duration. Regardless of condition, C. taurus spent a median of 98.9% of time swimming and 0.62% of time gliding. Healthy sharks spent a median of 0.67% gliding versus a median of 0% for afflicted sharks (p= 0.036), suggesting an increased swim-to-glide ratio among the latter group. All sharks swam asymmetrically in either a clockwise or counter-clockwise direction for a median of 99.7% of observed time. Affected specimens had tail beat durations of 3.37 ± 0.23 s vs. 2.72 ± 0.10 s for healthy sharks (p = 0.005). The increase in swim-to-glide ratios and inordinate time spent swimming asymmetrically for all affected sharks support the hypothesis that swimming patterns induced by captive exhibits may contribute to spinal deformities in C. taurus due to more stress placed on the spine. Large, complex aquarium designs are recommended in the planning of new exhibits to discourage stereotypical swimming behavior and also to provide sufficient length for sharks to complete natural swimming repertoires. Comprehensive behavioral enrichment activities that encourage complex movement are also recommended as well as considerations such as even weight distribution of the animal during capture, sourcing of appropriately aged sharks, and nutritional supplementation.
In the present study, researchers used contemporary attachment theory to explore the contributions of adult attachment styles on workers' preferences for relational leadership behaviors. A sample of ...617 workers in a retail organization across ten stores throughout the East, South, and Midwest completed measures of relationship attachment style and preferences for leadership behaviors. As hypothesized, findings revealed that workers with preoccupied adult attachment styles expressed stronger preferences for relational leadership behaviors than workers with either dismissive adult attachment styles or fearful attachment styles. Implications of the findings to advance a deeper understanding of workers' leadership behavioral preferences are discussed.
“Itʼs not who does it FIRST, itʼs who does it BEST.ˮ (David Bowie) Life on Mars David Bowie_Shot by Mick Rock_ was a hybrid exhibition presented at the collaborative and experimental multifunctional ...space Le Multiple in Toulouse, France, between 2 December 2016 and 15 January 2017: it combined various media from exquisite prints of photographs taken by Mick Rock through the glass showcases along the central axis of the exhibition space, containing original, and sometimes rare, contemporary do...
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