A Generic Algorithm for IACT Optical Efficiency Calibration using Muons

Muons produced in Extensive Air Showers (EAS) generate ring-like images in Imaging Atmospheric Cherenkov Telescopes when travelling near parallel to the optical axis. From geometrical parameters of these images, the absolute amount of light emitted may be calculated analytically. Comparing the amount of light recorded in these images to expectation is a well established technique for telescope optical efficiency calibration. However, this calculation is usually performed under the assumption of an approximately circular telescope mirror. The H.E.S.S. experiment entered its second phase in 2012, with the addition of a fifth telescope with a non-circular 600m$^2$ mirror. Due to the differing mirror shape of this telescope to the original four H.E.S.S. telescopes, adaptations to the standard muon calibration were required. We present a generalised muon calibration procedure, adaptable to telescopes of differing shapes and sizes, and demonstrate its performance on the H.E.S.S. II array.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherland

Potential for measuring the longitudinal and lateral profile of muons in TeV air showers with IACTs

Muons are copiously produced within hadronic extensive air showers (EAS) occurring in the Earth's atmosphere, and are used by particle air shower detectors as a means of identifying the primary cosmic ray which initiated the EAS. Imaging Atmospheric Cherenkov Telescopes (IACTs), designed for the detection of gamma-ray initiated EAS for the purposes of Very High Energy (VHE) gamma-ray astronomy, are subject to a considerable background signal due to hadronic EAS. Although hadronic EAS are typically rejected for gamma-ray analysis purposes, single muons produced within such showers generate clearly identifiable signals in IACTs and muon images are routinely retained and used for calibration purposes. For IACT arrays operating with a stereoscopic trigger, when a muon triggers one telescope, other telescopes in IACT arrays usually detect the associated hadronic EAS. We demonstrate for the first time the potential of IACT arrays for competitive measurements of the muon content of air showers, their lateral distribution and longitudinal profile of production slant heights in the TeV energy range. Such information can provide useful input to hadronic interaction models.Comment: 15 pages, 11 figures, 2 tables, accepted for publication in Astroparticle Physic

Scavenging vs hunting affects behavioral traits of an opportunistic carnivore

Background. Human-induced changes to ecosystems transform the availability of resources to predators, including altering prey populations and increasing access to anthropogenic foods. Opportunistic predators are likely to respond to altered food resources by changing the proportion of food they hunt versus scavenge. These shifts in foraging behavior will affect species interactions through multiple pathways, including by changing other aspects of predator behavior such as boldness, innovation, and social structure. Methods. To understand how foraging behavior impacts predator behavior, we conducted a controlled experiment to simulate hunting by introducing a prey model to captive coyotes (Canis latrans) and compared their behavior to coyotes that continued to scavenge over one year. We used focal observations to construct behavioral budgets, and conducted novel object, puzzle box, and conspecific tests to evaluate boldness, innovation, and response to conspecifics. Results. We documented increased time spent resting by hunting coyotes paired with decreased time spent active. Hunting coyotes increased boldness and persistence but there were no changes in innovation. Our results illustrate how foraging behavior can impact other aspects of behavior, with potential ecological consequences to predator ecology, predator-prey dynamics, and human-wildlife conflict; however, the captive nature of our study limits specific conclusions related to wild predators. We conclude that human-induced behavioral changes could have cascading ecological implications that are not fully understood

Effects of early‑life experience on innovation and problem‑solving in captive coyotes

Early-life experience often shapes behaviors like innovation and exploration. These behaviors are important to animals encountering novel food resources in diverse habitats, such as mesocarnivores in urban areas. To understand if early-life experiences impact later-life behavior, we examined how coyotes (Canis latrans) responded to a multi-access puzzle box at two life stages: pup (~ 7 weeks) and dispersal (~ 10 months). We first exposed pups, still living with their parents and littermates, to a baited puzzle box. At dispersal age, we again tested both these pups and an age-matched control group that was not exposed to the puzzle box as pups, both as individuals and with their pair-mate. We quantified problem-solving capability, latency to approach, and time spent in proximity to the puzzle box. Most pup litters solved two of the three access points, but no dispersal-age coyotes solved any access point. The amount of time dispersal-age coyotes spent near the box during pair-testing increased with (1) more time spent near the box during single-testing, (2) more time their pair-mate spent near the box during pair-testing, and (3) if their pair-mate came from a litter that previously solved the box. These results suggest that early-life experience and social interactions influence exploratory behavior at dispersal age, but coyotes exhibit increased avoidance behavior at this life stage, which corresponds with the life stage that overall survivorship decreases. Our study provides insight into how early-life experiences shape adult behavior in mesocarnivores

The H.E.S.S. II GRB Program

Gamma-ray bursts (GRBs) are some of the most energetic and exotic events in the Universe, however their behaviour at the highest energies (>10 GeV) is largely unknown. Although the Fermi-LAT space telescope has detected several GRBs in this energy range, it is limited by the relatively small collection area of the instrument. The H.E.S.S. experiment has now entered its second phase by adding a fifth telescope of 600 m$^{2}$ mirror area to the centre of the array. This new telescope increases the energy range of the array, allowing it to probe the sub-100 GeV range while maintaining the large collection area of ground based gamma-ray observatories, essential to probing short-term variability at these energies. We will present a description of the GRB observation scheme used by the H.E.S.S. experiment, summarising the behaviour and performance of the rapid GRB repointing system, the conditions under which potential GRB repointings are made and the data analysis scheme used for these observations.Comment: In Proceedings of the 34th International Cosmic Ray Conference (ICRC2015), The Hague, The Netherland

Prey of reintroduced fishers and their habitat relationships in the Cascades T Range, Washington

Conservation and recovery of forest carnivores requires an understanding of their habitat requirements, as well as requirements of their prey. In much of the western United States, trapping and habitat loss led to extirpations of fishers (Pekania pennanti) by the mid-20th century, and reintroductions are ongoing to restore fishers to portions of their former range. Fisher recovery in Washington State has been limited by isolation from other populations, but other potentially important factors, such as diet of fishers in this region and prey availability, have not been thoroughly investigated. We collected hair samples from potential prey and fishers for stable isotope analysis to identify important prey items for fishers within a reintroduction area in southern Washington. We then estimated the abundance of prey species at 21 sites across a gradient of forest structural classes within the fisher reintroduction area, and assessed the effects of forest age and vegetation on the prey community using permutational multivariate analysis of variance and non-metric multidimensional scaling. Stable isotopes revealed that larger prey items, including snowshoe hares (Lepus americanus) and/or mountain beavers (Aplodontia rufa), were the most important prey item(s) for fishers in the southern Cascades. We found distinct but equally diverse prey communities in old-growth (unmanaged) and young (heavily managed) forest stands, with snowshoe hares and mountain beavers most common in young forests, while chipmunks (Neotamius spp.) and small mammals were more common in older forests. Our results suggest a discrepancy between the habitats where important fisher prey are most abundant and habitat requirements of fishers. Snowshoe hares and mountain beavers were most abundant in young forests, whereas fishers are associated with landscapes dominated by older forest stands or those that provide large woody structures, which fishers use for denning and resting. Our results add to growing evidence that forest landscape mosaics provide valuable habitat for fishers in the Pacific Northwest, suggesting that both mature and younger forest stands are important for fishers and fisher recovery

Emergency ambulance service involvement with residential care homes in the support of older people with dementia : an observational study

© 2014 Amador et al.; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/2.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly credited. The Creative Commons Public Domain Dedication waiver (http://creativecommons.org/publicdomain/zero/1.0/) applies to the data made available in this article, unless otherwise stated.BACKGROUND: Older people resident in care homes have a limited life expectancy and approximately two-thirds have limited mental capacity. Despite initiatives to reduce unplanned hospital admissions for this population, little is known about the involvement of emergency services in supporting residents in these settings.METHODS: This paper reports on a longitudinal study that tracked the involvement of emergency ambulance personnel in the support of older people with dementia, resident in care homes with no on-site nursing providing personal care only. 133 residents with dementia across 6 care homes in the East of England were tracked for a year. The paper examines the frequency and reasons for emergency ambulance call-outs, outcomes and factors associated with emergency ambulance service use. RESULTS: 56% of residents used ambulance services. Less than half (43%) of all call-outs resulted in an unscheduled admission to hospital. In addition to trauma following a following a fall in the home, results suggest that at least a reasonable proportion of ambulance contacts are for ambulatory care sensitive conditions. An emergency ambulance is not likely to be called for older rather than younger residents or for women more than men. Length of residence does not influence use of emergency ambulance services among older people with dementia. Contact with primary care services and admission route into the care home were both significantly associated with emergency ambulance service use. The odds of using emergency ambulance services for residents admitted from a relative's home were 90% lower than the odds of using emergency ambulance services for residents admitted from their own home. CONCLUSIONS: Emergency service involvement with this vulnerable population merits further examination. Future research on emergency ambulance service use by older people with dementia in care homes, should account for important contextual factors, namely, presence or absence of on-site nursing, GP involvement, and access to residents' family, alongside resident health characteristics.Peer reviewedFinal Published versio

Science verification of the new FlashCam-based camera in the 28m telescope of H.E.S.S

In October 2019 the central 28m telescope of the H.E.S.S. experiment has beenupgraded with a new camera. The camera is based on the FlashCam design whichhas been developed in view of a possible future implementation in themedium-sized telescopes of the Cherenkov Telescope Array (CTA). We report hereon the results of the science verification program that has been performedafter commissioning of the new camera, to show that the camera and softwarepipelines are working up to expectations.<br

Cancer negatively impacts on sexual function in adolescents and young adults: The AYA HOPE study

ObjectiveThis cohort study examined the impact of cancer on sexual function and intimate relationships in adolescents and young adults (AYAs). We also explored factors predicting an increased likelihood that cancer had negatively affected these outcomes.MethodsParticipants (nâ =â 465, ages 15â 39) in the Adolescent and Young Adult Health Outcomes and Patient Experience (AYA HOPE) study completed two surveys approximately 1 and 2 years postâ cancer diagnosis. We used multivariable logistic regression to determine factors negatively affected by perceptions of sexual function at 2 years postâ diagnosis.ResultsFortyâ nine percent of AYAs reported negative effects on sexual function at 1 year postâ cancer diagnosis and 70% of those persisted in their negative perceptions 2 years after diagnosis. Those reporting a negative impact at 2 years were more likely to be 25 years or older (OR, 2.53; 95% CI, 1.44â 4.42), currently not raising children (OR, 1.81; 95% CI, 1.06â 3.08), experiencing fatigue (OR, 0.99; 95% CI, 0.975â 0.998) and more likely to report that their diagnosis has had a negative effect on physical appearance (OR, 3.08; 95% CI, 1.97â 4.81). Clinical factors and mental health were not significant predictors of negative effects on sexual function.ConclusionsMany AYAs diagnosed with cancer experience a persistent negative impact on sexual life up to 2 years following diagnosis. The findings underscore the need to develop routine protocols to assess sexual function in AYAs with cancer and to provide comprehensive management in the clinical setting. Copyright © 2016 John Wiley & Sons, Ltd.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/138867/1/pon4181_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/138867/2/pon4181.pd