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ABSTRACT We use Wide-field InfraRed Camera (WIRC) infrared (IR) images of the Antennae (NGC 4038/4039) together with the extensive catalogue of 120 X-ray point sources to search for counterpart candidates. Using our proven frame-tie technique, we find 38 X-ray sources with IR counterparts, almost doubling the number of IR counterparts to X-ray sources that we first identified. In our photometric analysis, we consider the 35 IR counterparts that are confirmed star clusters. We show that the clusters with X-ray sources tend to be brighter, Ks≈ 16 mag, with ( J− Ks) = 1.1 mag. We then use archival Hubble Space Telescope ( HST) images of the Antennae to search for optical counterparts to the X-ray point sources. We employ our previous IR-to-X-ray frame-tie as an intermediary to establish a precise optical-to-X-ray frame-tie with <0.6 arcsec rms positional uncertainty. Due to the high optical source density near the X-ray sources, we determine that we cannot reliably identify counterparts. Comparing the HST positions to the 35 identified IR star cluster counterparts, we find optical matches for 27 of these sources. Using Bruzual-Charlot spectral evolutionary models, we find that most clusters associated with an X-ray source are massive, and young, ∼ 106 yr. [ABSTRACT FROM AUTHOR] more...

We report intensive monitoring of the activity variability in the Hα line for 10 Sun-like stars using the 1.88 m reflector at Okayama Branch Office, Subaru Telescope, during the last four years (2019–2022). Our aim was to investigate features of the stellar magnetic activity behavior. We correlated the Hα line variability of each star with the stellar activity levels derived from the Ca  ii H&K line, suggesting its efficiency as a magnetic activity indicator. In analyzing the Hα line variation, we observed that some stars exhibited linear or quadratic trends during the observation period. Among several G- and K-type stars expected to have co-existing activity cycles, we confirmed the 2.9 yr short cycle of ϵ Eri (K2V) from the Hα observations. Additionally, we established upper limits on the Hα variability of β Com (G0V) and κ1 Cet (G5V) concerning their expected shorter cycles. We also detected the possibility of short-term activity cycles in two F-type stars, β Vir (F9V; ∼530 d) and α CMi (F5IV-V; ∼130 d). The cycle in α CMi was observed in only one season of our 4 yr observations, suggesting the temporal absence of the cycle period. However, for stars with planets, we did not observe significant magnetic activity variability likely associated with the planetary orbital period. It is speculated that the impact of Hα variability on radial velocity (RV) measurements may vary with spectral type. [ABSTRACT FROM AUTHOR] more...

Fomalhaut b is an extrasolar object that was imaged directly in 2008. Its status since has changed from exoplanet – including super-Earth and low-mass candidates – to neutron star to dust cloud, generating contention, controversy, and confusion. We contribute to the discussion by reporting additional evidence that, given a set containing celestial objects classified as exoplanets, Fomalhaut b might be a non-member. We conducted a principal component (PC) analysis on a data set containing 425 extrasolar objects and 7 variables and found a single isolated point in PC space representing Fomalhaut b. Whatever its existential status, Fomalhaut b is characterized by properties very different from those characterizing exoplanets. [ABSTRACT FROM AUTHOR] more...

The water permeability of the stratum corneum (SC) appears to be regulated primarily by the lamellar arrangement of lipid bilayers between the corneocytes. A significant body of evidence already exists, suggesting that the specific structural organization of these intercellular lipid lamellae is responsible for the very low water permeability of the intact skin and that these lipid-rich structures may also influence the process of desquamation in the SC. In this electron microscopic study the structure of the intercellular domains at different levels within the SC of normal skin from 18 healthy subjects has been evaluated with a special fixation protocol utilizing acrolein vapour as primary fixation, followed by a modified ruthenium tetroxide (RuO4)-post-fixation technique. This procedure permitted an insight into the process of post-secretory extracellular processing of the lamellar body (LB)-derived lipids into lamellar lipid bilayers. This transformation takes place in unique saccular invaginations of the intercellular domains, which indent the underlying stratum granulosum (SG) cells. In this specialized environment LB lipids arc first processed into broad sheets before they become part of the typical lamellar lipid structure of the SC. Furthermore. In the process of lipid maturation distinct differences between inner and outer parts of the SC emerge, in particular an increase in both the number of the lamellae per intercellular space, and their order of arrangement. Moreover, distinct structural relationships between desmosomes (at the SG/SC interface and lower SC) and desmosomal remnants (at the stratum disjunctum) on the one hand, and lipid layers on the other, have been demonstrated, pointing to an important functional interaction of these components in normal human skin. [ABSTRACT FROM AUTHOR] more...

Information on several topics discussed at the Ruminant Nutrition Symposium titled "The Impact of the Rumen Microbiome on Nutrition, Health and Production," held at the Joint Annual Meeting of the American Society of Animal Science and the American Dairy Science Association in Kansas City, Missouri from July 20 to 24, 2014 is presented. Topics include the study of microbiome in the rumen and the application of microbiome research on dairy and beef cattle nutrition, health, and production. more...