704 research outputs found
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Impacts of Wetland Restoration Efforts on an Amphibian Assemblage in a Multi-invader Community
The success of restoration in attaining wildlife conservation goals can be strongly dependent on both site-scale and landscape-scale habitat characteristics, particularly for species with complex life cycles. Wetland management activities typically target plant communities, and bottom-up responses in higher trophic levels may be dependent on spatially explicit habitat use. We surveyed plant and amphibian assemblages at 26 sites enrolled in the Wetlands Reserve Program (WRP) in the Willamette Valley, Oregon to determine the relative influence of plant management, non-native species, and surrounding landscape on amphibian counts across multiple life history stages. Explanatory variables negatively associated with native anuran counts included percent invasive plant cover, non-native fish presence, invasive bullfrog counts, and area of urban land cover. In addition, native anurans were positively associated with WRP site age, suggesting that the benefits of restored wetlands may increase over time. This study emphasized the importance of adaptive approaches to maintaining diverse communities in restored habitats by considering impacts of synergistic stressors in a multi-invader context. Although invasive plant management provided indirect benefits to native amphibians, the most effective way to enhance native amphibian populations may be through eliminating the strong top-down forces exerted by non-native vertebrates.Keywords: WRP, Invasive species, Landscape, Restoration, Wetlands, Amphibian
The Genesis 12–19 (G1219) Study: A Twin and Sibling Study of Gene–Environment Interplay and Adolescent Development in the UK
The Genesis 12–19 (G1219) Study is an ongoing longitudinal study of a sample of UK twin pairs, non-twin sibling pairs, and their parents. G1219 was initially designed to examine the role of gene–environment interplay in adolescent depression. However, since then data have continued to be collected from both parents and their offspring into young adulthood. This has allowed for longitudinal analyses of depression and has enabled researchers to investigate multiple phenotypes and to ask questions about intermediate mechanisms. The study has primarily focused on emotional development, particularly depression and anxiety, which have been assessed at multiple levels of analysis (symptoms, cognitions, and relevant environmental experiences). G1219 has also included assessment of a broader range of psychological phenotypes ranging from antisocial behaviors and substance use to sleep difficulties, in addition to multiple aspects of the environment. DNA has also been collected. The first wave of data collection began in the year 1999 and the fifth wave of data collection will be complete before the end of 2012. In this article, we describe the sample, data collection, and measures used. We also summarize some of the key findings to date
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A tad too high: Sensitivity to UV-B radiation may limit invasion potential of American bullfrogs (Lithobates catesbeianus) in the Pacific Northwest invasion range
Biological invasion potential can be strongly influenced by abiotic factors such as temperature, water availability, and solar radiation. Invasive species that possess phenotypically plastic traits can mediate impacts from these stressors, but may be unable to recognize and respond to dangerous levels in a novel environment. Understanding potential constraints on appropriate trait responses induced by abiotic stressors can aid in the management and control of important invaders. Our study explored tolerance and plastic trait response to UV-B radiation in an invasive anuran, the American bullfrog (Lithobates catesbeianus Shaw, 1802). We experimentally quantified larval mortality rates and color change responses across two larval size classes. In a second experiment, we investigated the potential for a correlated color change and behavioral (refuge use) response in the small size class. We predicted that individuals would respond to stressful and potentially harmful UV-B exposure rates with darkening of body coloration, and when refuge was available, a correlated defense strategy utilizing both color change and refuge. We found an increase in larval mortality across both size classes at UV-B exposure rates typical to both low and high elevation aquatic breeding sites (10-12 μW/cm² and 20-24 μW/cm² , respectively). Only bullfrog larvae in the small size class exhibited a darkening in body color when exposed to high UV-B treatments. Although this smaller size class did exhibit color plasticity, individuals did not correlate changes in body coloration with changes in refuge use. These results suggest ontogenetic differences (estimated by size class) in plastic color response to UV-B stress as well as constraints on behavioral use of refuge. These findings are important in understanding differences in bullfrog occupancy of breeding habitats across an elevational gradient, particularly in Oregon’s Cascade Mountain Range, where bullfrog distributions are currently limited at elevations above 1000 m.Keywords: Amphibian, Ultraviolet radiation, Color,
Plasticity,
American bullfrog,
Invasion,
BehaviorThis is the publisher’s final pdf. The published article is copyrighted by the author(s) and published by the Regional Euro-Asian Biological Invasions Centre
Detection of Potential Transit Signals in Sixteen Quarters of Kepler Mission Data
We present the results of a search for potential transit signals in four
years of photometry data acquired by the Kepler Mission. The targets of the
search include 111,800 stars which were observed for the entire interval and
85,522 stars which were observed for a subset of the interval. We found that
9,743 targets contained at least one signal consistent with the signature of a
transiting or eclipsing object, where the criteria for detection are
periodicity of the detected transits, adequate signal-to-noise ratio, and
acceptance by a number of tests which reject false positive detections. When
targets that had produced a signal were searched repeatedly, an additional
6,542 signals were detected on 3,223 target stars, for a total of 16,285
potential detections. Comparison of the set of detected signals with a set of
known and vetted transit events in the Kepler field of view shows that the
recovery rate for these signals is 96.9%. The ensemble properties of the
detected signals are reviewed.Comment: Accepted by ApJ Supplemen
Acute Management and Outcomes of Patients with Diabetes Mellitus Presenting to Canadian Emergency Departments with Hypoglycemia
Objectifs: Cette vérification rétrospective des dossiers a permis d\u27examiner les données démographiques, les examens, la prise en charge et les résultats des patients adultes souffrant de diabète sucré qui se sont présentés aux services des urgences (SU) au Canada. Méthodes: Tous les sites ont mené une recherche dans leurs dossiers médicaux électroniques à l\u27aide des codes de la Classification internationale des maladies, dixième révision, pour relever les visites aux SU entre 2008 et 2010 qui étaient liées à l\u27hypoglycémie. Les caractéristiques des patients, les données démographiques, la prise en charge aux SU, les ressources des SU et les résultats sont rapportés. Résultats: Un total de 1039 patients de plus de 17 ans ont été inclus dans l\u27étude; 347 (33,4 %) ont été classifiés comme étant des cas de diabète de type 1 et 692 (66,6 %) ont été classifiés comme étant des cas de diabète de type 2. Les patients souffrant du diabète de type 2 étaient beaucoup plus âgés (73 ans vs 49 ans; p\u3c0,0001) et avaient plus d\u27affections chroniques inscrites à leur dossier (tous p\u3c0,001). La plupart des sujets arrivaient par ambulance, et 39 % des cas montraient des scores de triage qui révélaient des tableaux cliniques graves. Les traitements contre l\u27hypoglycémie étaient fréquents (75,7 %) durant le transport préhospitalier; 38,5 % recevaient du glucose et 40,1 % recevaient du glucagon par voie intraveineuse. Les traitements administrés dans les SU contre l\u27hypoglycémie comprenaient le glucose par voie orale (76,8 %), le glucose par voie intraveineuse (29,6 %) et en perfusion continue (27,7 %). Les examens diagnostiques (81,9 %) comprenaient fréquemment les électrocardiogrammes (51,9 %), la radiographie thoracique (37,5 %) et la tomodensitométrie crânienne (14,5 %). La plupart des patients (73,5 %) recevaient leur congé. Cependant, plus de sujets souffrant du diabète de type 2 nécessitaient une admission (30,3 vs 8,8 %). Les instructions de congé étaient étayées chez seulement 55,5 % des patients, et l\u27orientation vers des services de diabète se rencontrait chez moins de 20 % des cas. Une variation considérable dans la prise en charge de l\u27hypoglycémie existait entre les SU. Conclusions: Les patients souffrant de diabète qui se présentaient à un SU en raison d\u27une hypoglycémie consomment considérablement de ressources en soins de santé, puis une variation est observée dans la pratique. Les SU devraient élaborer des protocoles de prise en charge de l\u27hypoglycémie en portant une attention à la planification du congé pour réduire la récurrence
Duration and urgency of transfer in births planned at home and in freestanding midwifery units in England: secondary analysis of the Birthplace national prospective cohort study
Background: In England, there is a policy of offering healthy women with straightforward pregnancies a choice of birth setting. Options may include home or a freestanding midwifery unit (FMU). Transfer rates from these settings are around 20%, and higher for nulliparous women. The duration of transfer is of interest because of the potential for delay in access to specialist care and is also of concern to women. We aimed to estimate the duration of transfer in births planned at home and in FMUs and explore the effects of distance and urgency on duration.
Methods: This was a secondary analysis of data collected in a national prospective cohort study including 27,842 ‘low risk’ women with singleton, term, ‘booked’ pregnancies, planning birth in FMUs or at home in England from April 2008 to April 2010. We described transfer duration using the median and interquartile range, for all transfers and those for reasons defined as potentially urgent or non-urgent, and used cumulative distribution curves to compare transfer duration by urgency. We explored the effect of distance for transfers from FMUs and described outcomes in women giving birth within 60 minutes of transfer.
Results: The median overall transfer time, from decision to transfer to first OU assessment, was shorter in transfers from home compared with transfers from FMUs (49 vs 60 minutes; p < 0.001). The median duration of transfers before birth for potentially urgent reasons (home 42 minutes, FMU 50 minutes) was 8–10 minutes shorter compared with transfers for non-urgent reasons. In transfers for potentially urgent reasons, the median overall transfer time from FMUs within 20 km of an OU was 47 minutes, increasing to 55 minutes from FMUs 20-40 km away and 61 minutes in more remote FMUs. In women who gave birth within 60 minutes after transfer, adverse neonatal outcomes occurred in 1-2% of transfers.
Conclusions: Transfers from home or FMU commonly take up to 60 minutes from decision to transfer, to first assessment in an OU, even for transfers for potentially urgent reasons. Most transfers are not urgent and emergencies and adverse outcomes are uncommon, but urgent transfer is more likely for nulliparous women
Planetary Candidates Observed by Kepler. VII. The First Fully Uniform Catalog Based on The Entire 48 Month Dataset (Q1-Q17 DR24)
We present the seventh Kepler planet candidate catalog, which is the first to
be based on the entire, uniformly processed, 48 month Kepler dataset. This is
the first fully automated catalog, employing robotic vetting procedures to
uniformly evaluate every periodic signal detected by the Q1-Q17 Data Release 24
(DR24) Kepler pipeline. While we prioritize uniform vetting over the absolute
correctness of individual objects, we find that our robotic vetting is overall
comparable to, and in most cases is superior to, the human vetting procedures
employed by past catalogs. This catalog is the first to utilize artificial
transit injection to evaluate the performance of our vetting procedures and
quantify potential biases, which are essential for accurate computation of
planetary occurrence rates. With respect to the cumulative Kepler Object of
Interest (KOI) catalog, we designate 1,478 new KOIs, of which 402 are
dispositioned as planet candidates (PCs). Also, 237 KOIs dispositioned as false
positives (FPs) in previous Kepler catalogs have their disposition changed to
PC and 118 PCs have their disposition changed to FP. This brings the total
number of known KOIs to 8,826 and PCs to 4,696. We compare the Q1-Q17 DR24 KOI
catalog to previous KOI catalogs, as well as ancillary Kepler catalogs, finding
good agreement between them. We highlight new PCs that are both potentially
rocky and potentially in the habitable zone of their host stars, many of which
orbit solar-type stars. This work represents significant progress in accurately
determining the fraction of Earth-size planets in the habitable zone of
Sun-like stars. The full catalog is publicly available at the NASA Exoplanet
Archive.Comment: Accepted to the Astrophysical Journal Supplement Series. 30 pages, 9
figures, 7 tables. We make the DR24 robovetter decision code publicly
available at http://github.com/JeffLCoughlin/robovetter, with input and
output examples provided using the same data as contained in the full paper's
table
Planetary Candidates Observed by Kepler V: Planet Sample from Q1-Q12 (36 Months)
The Kepler mission discovered 2842 exoplanet candidates with 2 years of data.
We provide updates to the Kepler planet candidate sample based upon 3 years
(Q1-Q12) of data. Through a series of tests to exclude false-positives,
primarily caused by eclipsing binary stars and instrumental systematics, 855
additional planetary candidates have been discovered, bringing the total number
known to 3697. We provide revised transit parameters and accompanying posterior
distributions based on a Markov Chain Monte Carlo algorithm for the cumulative
catalogue of Kepler Objects of Interest. There are now 130 candidates in the
cumulative catalogue that receive less than twice the flux the Earth receives
and more than 1100 have a radius less than 1.5 Rearth. There are now a dozen
candidates meeting both criteria, roughly doubling the number of candidate
Earth analogs. A majority of planetary candidates have a high probability of
being bonafide planets, however, there are populations of likely
false-positives. We discuss and suggest additional cuts that can be easily
applied to the catalogue to produce a set of planetary candidates with good
fidelity. The full catalogue is publicly available at the NASA Exoplanet
Archive.Comment: Accepted for publication, ApJ
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