The Annual Migration Cycle of Emperor Geese in Western Alaska

Most emperor geese (Chen canagica) nest in a narrow coastal region of the Yukon-Kuskokwim Delta (YKD) in western Alaska, but their winter distribution extends more than 3000 km from Kodiak Island, Alaska, to the Commander Islands, Russia. We marked 53 adult female emperor geese with satellite transmitters on the YKD in 1999, 2002, and 2003 to examine whether chronology of migration or use of seasonal habitats differed among birds that wintered in different regions. Females that migrated relatively short distances (650–1010 km) between the YKD and winter sites on the south side of the Alaska Peninsula bypassed autumn staging areas on the Bering Sea coast of the Alaska Peninsula or used them for shorter periods (mean = 57 days) than birds that made longer migrations (1600–2640 km) to the western Aleutian Islands (mean = 97 days). Alaska Peninsula migrants spent more days at winter sites (mean = 172 days, 95% CI: 129–214 days) than western Aleutian Island migrants (mean = 91 days, 95% CI: 83–99 days). Birds that migrated 930–1610 km to the eastern Aleutian Islands spent intermediate intervals at fall staging (mean = 77 days) and wintering areas (mean = 108 days, 95% CI: 95–119 days). Return dates to the YKD did not differ among birds that wintered in different regions. Coastal staging areas on the Alaska Peninsula may be especially important in autumn to prepare Aleutian migrants physiologically for long-distance migration to winter sites, and in spring to enable emperor geese that migrate different distances to reach comparable levels of condition before nesting.La plupart des oies empereurs (Chen canagica) nichent dans une étroite région côtière du delta Yukon-Kuskokwim (DYK), dans l’ouest de l’Alaska. Cependant, l’hiver, leur répartition hivernale s’étend sur plus de 3000 km, depuis l’île de Kodiak, en Alaska, jusqu’aux îles Commander, en Russie. Nous avons apposé à 53 oies empereurs femelles adultes du DYK des transmetteurs satellites en 1999, 2002 et 2003 dans le but d’examiner si la chronologie de la migration ou l’utilisation des habitats saisonniers différaient chez les oiseaux qui hivernaient dans des régions différentes. Les femelles dont la migration se faisait sur des distances assez courtes (de 650 à 1010 km) entre le DYK et les lieux d’hivernage du côté sud de la péninsule de l’Alaska contournaient les haltes migratoires de la côte de la mer de Béring de la péninsule de l’Alaska ou s’en servaient pendant de plus courtes périodes (moyenne = 57 jours) que les oiseaux dont les migrations étaient plus longues (de 1600 à 2 640 km) vers les îles Aléoutiennes de l’Ouest (moyenne = 97 jours). Les migrants de la péninsule de l’Alaska passaient plus de jours aux lieux d’hivernage (moyenne = 172 jours, 95 % IC : 129–214 jours) que les migrants des îles Aléoutiennes de l’Ouest (moyenne = 91 jours, 95 % IC : 83–99 jours). Les oiseaux dont la migration se faisait de 930 à 1 610 km vers les îles Aléoutiennes de l’Est passaient des intervalles intermédiaires aux haltes migratoires de l’automne (moyenne = 77 jours) et aux aires d’hivernage (moyenne = 108 jours, 95 % IC : 95–119 jours). Les dates de retour au DYK ne différaient pas chez les oiseaux qui hivernaient dans des régions différentes. Les haltes migratoires côtières de la péninsule de l’Alaska pourraient revêtir une importance particulière à l’automne, en ce sens qu’elles permettent aux migrants des Aléoutiennes de se préparer physiologiquement à la migration de longue distance menant aux lieux d’hivernage, et le printemps, elles permettent aux oies empereurs qui migrent sur diverses distances d’atteindre des degrés de condition comparables avant la nidification

Valuation Of The Embedded Option In A Non-Cancelable Lease: Theory And Application

This paper applies a “real” option literature based model to valuing the option element of a non-cancelable lease without an early exercise provision. The model is applied to a common lease type – the closed-end automobile lease. The findings show that the value of the option inherent in an automobile lease is approximately two to six percent of the original asset cost. The analysis discusses ways in which the option value can be captured through the lease contract terms. Management decision makers can use these concepts in evaluating lease/purchase decisions

Evaluation of variables for the communication of uncertainties using peripheral awareness displays

The communication of system uncertainties may be key for overcoming challenges related to overtrust in automated driving. Existing approaches are limited to conveying uncertainties using visual displays in the instrument cluster. This requires operators to regularly monitor the display in order to perceive changes which impedes the execution of nondriving related tasks and thereby degrades the user experience. This study evaluates variables for the communication of uncertainties using peripheral awareness displays, considering changes in brightness, hue, position, size, pulse frequency, and movement speed. All variables were assessed in terms of how well participants can distinguish different instances, how logical they are, and how interrupting to a secondary task. With the exception of changes in position, all variables were ranked highly in terms of logic while changes in pulse frequency were perceived as most interrupting. The results inform the development of unobtrusive interfaces for uncertainty communication

Healing Through History: a qualitative evaluation of a social medicine consultation curriculum for internal medicine residents

Background: Social context guides care; stories sustain meaning; neither is routinely prioritized in residency training. Healing Through History (HTH) is a social medicine consultation curriculum integrating social determinants of health narrative into clinical care for medically and socially complex patients. The curriculum is part of an internal medicine (IM) residency outpatient clinical rotation at a Veterans Health Administration hospital. Our aim was to explore how in-depth social medicine consultations may impact resident clinical practice and foster meaning in work. Methods: From 2017 to 2019, 49 categorical and preliminary residents in their first year of IM training were given two half-day sessions to identify and interview a patient; develop a co-produced social medicine narrative; review it with patient and faculty; and share it in the electronic health record (EHR). Medical anthropologists conducted separate 90-min focus groups of first- and second-year IM residents in 2019, 1–15 months from the experience. Results: 46 (94%) completed HTH consultations, of which 40 (87%) were approved by patients and published in the EHR. 12 (46%) categorical IM residents participated in focus groups; 6 PGY1, and 6 PGY2. Qualitative analysis yielded 3 themes: patient connection, insight, and clinical impact; clinical skill development; and structural barriers to the practice of social medicine. Conclusions: HTH offers a model for teaching co-production through social and narrative medicine consultation in complex clinical care, while fostering meaning in work. Integration throughout training may further enhance impact

Untangling the X-ray Emission From the Sa Galaxy NGC1291 With Chandra

We present a Chandra ACIS-S observation of the nearby bulge-dominated Sa galaxy NGC1291. The X-ray emission from the bulge resembles the X-ray emission from a sub-class of elliptical and S0 galaxies with low L_X/L_B luminosity ratios. The X-ray emission is composed of a central point-like nucleus, ~50 point sources that are most likely low mass X-ray binaries (LMXBs), and diffuse gas detectable out to a radius of 120" (5.2 kpc). The diffuse gas has a global temperature of 0.32^{+0.04}_{-0.03} keV and metallicity of 0.06 +/- 0.02 solar, and both quantities marginally decrease with increasing radius. The hot gas fills the hole in the HI distribution, and the softening of the spectrum of the X-ray gas with radius might indicate a thermal coupling of the hot and cold phases of the interstellar medium as previously suggested. The integrated X-ray luminosity of the LMXBs, once normalized by the optical luminosity, is a factor of 1.4 less than in the elliptical galaxy NGC4697 or S0 galaxy NGC1553. The difference in L_{X,stellar}/L_B between the galaxies appears to be because of a lack of very bright sources in NGC1291. No sources above 3 x 10^38 ergs/s were found in NGC1291 when ~7 were expected from scaling from NGC4697 and NGC1553. The cumulative L_{X,stellar}/L_B value including only sources below 1.0 x 10^38 ergs/s is remarkably similar between NGC1291 and NGC4697, if a recent surface brightness fluctuation-determined distance is assumed for NGC4697. If this is a common feature of the LMXB population in early-type systems, it might be used as a distance indicator. Finally, a bright, variable (1.6-3.1 x 10^39 ergs/s) source was detected at the optical center of the galaxy. Its spectrum shows excess soft emission superimposed on a highly absorbed power law component, similar to what has been found in several other low luminosity AGN (ABRIDGED).Comment: 13 pages in emulateapj5 style with 11 embedded Postscript figures; minor revisions since last version; accepted by Ap

Changes in posterior scleral collagen microstructure in canine eyes with an ADAMTS10 mutation

Purpose: We aimed to characterize alterations in the posterior scleral collagen microstructure before detectable disease onset in a canine model of open-angle glaucoma caused by an ADAMTS10 mutation. Methods: Collagen orientation, anisotropy degree (proportion of preferentially aligned collagen), and relative density were measured at 0.4 mm spatial resolution using synchrotron wide-angle X-ray scattering. For statistical evaluation of structure parameters, regional averages of the peripapillary and mid-posterior sclera were compared between ADAMTS10 mutant (affected) dogs (n = 3) and age-matched (carrier) controls (n = 3). Results: No marked differences in the general pattern of preferential collagen fibril orientation were noted between the control and affected dogs. The peripapillary sclera of all specimens featured strongly aligned circumferential collagen ringing the optic nerve head. Collagen anisotropy was significantly reduced in the mid-posterior sclera of the affected dogs (carrier: 0.27±0.11; affected: 0.24±0.10; p = 0.032) but was not statistically significantly different in the peripapillary sclera (carrier: 0.46±0.15; affected: 0.45±0.17; p = 0.68). Collagen density was statistically significantly reduced in the affected dogs for the mid-posterior sclera (carrier: 28.1±9.14; affected: 18.3±5.12; p<0.0001) and the peripapillary sclera (carrier: 34.6±9.34; affected: 21.1±6.97; p = 0.0002). Conclusions: Significant alterations in the posterior scleral collagen microstructure are present before the onset of clinical glaucoma in ADAMTS10 mutant dogs. A reduction in fibrous collagen density is likely an important contributory factor in the previously reported mechanical weakening of the sclera in this model. Baseline scleral abnormalities have the potential to interact with intraocular pressure (IOP) elevations in determining the course of glaucoma progression in animal models of the disease, and potentially in human glaucoma

Testing general relativity with accretion onto compact objects

The X-ray emission of neutron stars and black holes presents a rich phenomenology that can lead us to a better understanding of their nature and to address more general physics questions: Does general relativity apply in the strong gravity regime? Is spacetime around black holes described by the Kerr metric? This white paper considers how we can investigate these questions by studying reverberation mapping and quasi-periodic oscillations in accreting systems with a combination of high-spectral and high-timing resolution. In the near future, we will be able to study compact objects in the X-rays in a new way: advancements in transition-edge sensors (TES) technology will allow for electron-volt-resolution spectroscopy combined with nanoseconds-precision timing.Comment: White paper submitted for Astro2020 Decadal Survey. 8 pages, 2 figure

An infrared survey of brightest cluster galaxies: Paper I

We report on an imaging survey with the Spitzer Space Telescope of 62 brightest cluster galaxies with optical line emission. These galaxies are located in the cores of X-ray luminous clusters selected from the ROSAT All-Sky Survey. We find that about half of these sources have a sign of excess infrared emission; 22 objects out of 62 are detected at 70 microns, 18 have 8 to 5.8 micron flux ratios above 1.0 and 28 have 24 to 8 micron flux ratios above 1.0. Altogether 35 of 62 objects in our survey exhibit at least one of these signs of infrared excess. Four galaxies with infrared excesses have a 4.5/3.6 micron flux ratio indicating the presence of hot dust, and/or an unresolved nucleus at 8 microns. Three of these have high measured [OIII](5007A)/Hbeta flux ratios suggesting that these four, Abell 1068, Abell 2146, and Zwicky 2089, and R0821+07, host dusty active galactic nuclei (AGNs). 9 objects (including the four hosting dusty AGNs) have infrared luminosities greater than 10^11 L_sol and so can be classified as luminous infrared galaxies (LIRGs). Excluding the four systems hosting dusty AGNs, the excess mid-infrared emission in the remaining brightest cluster galaxies is likely related to star formation.Comment: accepted for publication in ApJ

The X-ray Faint Early-Type Galaxy NGC4697

We analyze archival ROSAT HRI, ROSAT PSPC, and ASCA data of the X-ray faint early-type galaxy NGC4697. The joint ROSAT PSPC + ASCA spectrum is fit by a two-component thermal model, a MEKAL model with kT_{MEKAL}=0.26^{+0.04}_{-0.03} keV with low metallicity and a bremsstrahlung model with kT_{BREM}=5.2^{+3.0}_{-1.6} keV. A similar model was found to fit the spectra of another faint early-type galaxy (NGC4382) and the bulge of M31. We interpret this soft emission as a combination of emission from a soft component of low mass X-ray binaries (LMXBs) and from a low temperature interstellar medium, although the relative contributions of the two components could not be determined. Twelve point sources were identified within 4' of NGC4697, of which 11 are most likely LMXBs associated with the galaxy. The soft X-ray colors of four of the LMXBs in NGC4697 support the claim that LMXBs possess a soft spectral component. Finally, we present a simulation of what we believe the Chandra data of NGC4697 will look like.Comment: 10 pages, uses emulateapj.sty, accepted by Astrophysical Journa