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Feeling socially connected and focusing on growth: Relationships with well-being during a major holiday in the COVID-19 pandemic
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Spectral analysis of craters on (101955) Bennu
No full text© 2020 Elsevier Inc. Using data acquired by the OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, and Security–Regolith Explorer) mission, we investigate spectral properties of craters on the near-Earth asteroid (101955) Bennu. We compare Bennu\u27s craters with its global average by means of four spectral parameters: (a) minimum position of the band at 2.7 μm, (b) depth of the hydrated phyllosilicate absorption band at 2.7 μm, (c) normalized spectral slope from 0.55 to 2.0 μm, and (d) reflectance factor at 0.55 μm. We examine 45 craters using spectral data obtained under various observing conditions. For 20 craters, we find a shortward shift of the 2.7-μm band minimum relative to the global 2.7-μm band minimum, which we attribute to the presence of relatively fresh (less space-weathered) material excavated from the sub-surface by crater-forming impacts. For three craters, we find an anti-correlation between spectral slopes and reflectance factor for a series of spectra acquired during a specific scan, where we observe that spectra become redder and darker towards the center of the crater. We attribute this to the presence of fine-particulate regolith. Localized spectral heterogeneities are apparent inside a prominent equatorial crater on Bennu, which is one of the asteroid\u27s oldest geological features. We propose that such local spectral heterogeneities could be used as a tracer of mass movement on Bennu. We show that younger craters are redder, brighter, and have deeper 2.7-μm bands. Comparing global average spectral values of Bennu and crater frequency distributions as a function of the chosen spectral parameters, we find that craters evolve to assume the global average spectral properties of Bennu. A positive correlation identified between the reflectance factor and 2.7-μm band depth suggests that brighter craters tend to be more hydrated. Finally, we put into context, the results from the Small Carry-on Impactor experiment by the Hayabusa2 spacecraft, which created an artificial crater on the near-Earth asteroid (162173) Ryugu
A sense of presence: mediating an american apocalypse
No full text© 2021 by the author. Li-censee MDPI, Basel, Switzerland. Here I build upon Robert Orsi’s work by arguing that we can see presence—and the longing for it—at work beyond the obvious spaces of religious practice. Presence, I propose, is alive and well in mediated apocalypticism, in the intense imagination of the future that preoccupies those who consume its narratives in film, games, and role plays. Presence is a way of bringing worlds beyond into tangible form, of touching them and letting them touch you. It is, in this sense, that Michael Hoelzl and Graham Ward observe the “re-emergence” of religion with a “new visibility” that is much more than “simple re-emergence of something that has been in decline in the past but is now manifesting itself once more.” I propose that the “new awareness of religion” they posit includes the mediated worlds that enchant and empower us via deeply immersive fandoms. Whereas religious institutions today may be suspicious of presence, it lives on in the thick of media fandoms and their material manifestations, especially those forms that make ultimate promises about the world to come
Use of time-to-boundary to assess postural instability and predict functional mobility in people with diabetes mellitus and peripheral neuropathy
No full text© 2020 Elsevier B.V. Background: People with diabetes mellitus and peripheral neuropathy (DMPN) often have balance and mobility deficits. Time-to-boundary (TTB) is a parameter of postural control that combines position and velocity center of pressure data. While not previously investigated, assessment of TTB may provide new insight regarding postural control in people with DMPN. Research question: Is TTB reduced and related to a measure of mobility in people with DMPN? Methods: Thirteen people with DMPN without fall history and 13 healthy matched controls participated in this case-control study. Participants stood in double-limb stance on a force plate. The anterior-posterior and medial-lateral center of pressure position and velocity relative to the boundaries of the base of support were used to calculate TTB (s). Lower values indicate less postural control. Time-to-failure during single-limb stance was a secondary measure of postural control. Time to complete the Timed Up and Go (TUG) was our measure of mobility. Longer TUG times correspond to decreased mobility, strength, and balance. Independent t-tests or Mann-Whitney U tests were conducted to assess group differences. Bivariate correlations between task outcomes were conducted. Results: Anterior-posterior TTB and single-limb stance times were shorter in people with DMPN (p ≤ 0.04). TUG times were longer in the DMPN group (p = 0.04). In the DMPN group, inverse relationships were observed between TTB and TUG (anterior-posterior R2 = .34; medial-lateral R2 = .49; both p = 0.01), but not between single-limb stance times and TTB or TUG. Significance: TTB was a sensitive measure of postural control in people with DMPN. The detected relationship between TTB and TUG newly establishes TTB as a clinically meaningful indicator of balance and function. Study findings may serve to further guide balance screening and rehabilitation efforts in people with DMPN
