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Paleoecological data from the Quaternary Period (2.6 million years ago to present) provides an opportunity for educational outreach for the earth and biological sciences. Paleoecology data repositories serve as technical hubs and focal points within their disciplinary communities and so are uniquely situated to help produce teaching modules and engagement resources. The Neotoma Paleoecology Database provides support to educators from primary schools to graduate students. In collaboration with pedagogical experts, the Neotoma Paleoecology Database team has developed teaching modules and model workflows. Early education is centered on discovery; higher-level educational tools focus on illustrating best practices for technical tasks. Collaborations among pedagogic experts, technical experts and data stewards, centered around data resources such as Neotoma, provide an important role within research communities, and an important service to society, supporting best practices, translating current research advances to interested audiences, and communicating the importance of individual research disciplines.
Oral anticoagulation (OAC) reduces stroke risk in patients with atrial fibrillation (AF) or atrial flutter (AFL). However, OAC initiation rates in patients discharged directly from the emergency department (ED) are low. We aimed to address this care gap by implementing a quality improvement intervention.
The study was performed in four Canadian urban EDs between 2015 and 2016. Patients were included if they had an electrocardiogram (ECG) documenting AF/AFL in the ED, were directly discharged from the ED, and were alive after 90 days. Baseline rates of OAC initiation were determined prior to the intervention. Between June and December 2016, we implemented our intervention in two EDs (ED-intervention), with the remaining sites acting as controls (ED-control). The intervention included a reminder statement prompting OAC initiation according to guideline recommendations, manually added to ECGs with a preliminary interpretation of AF/AFL, along with a decision-support algorithm that included a referral sheet. The primary outcome was the rate of OAC initiation within 90 days of the ED visit.
Prior to the intervention, 37.2% OAC-naïve patients with ECG-documented AF/AFL were initiated on OAC. Following implementation of the intervention, the rate of OAC initiation increased from 38.6% to 47.5% (absolute increase of 8.5%; 95% CI, 0.3% to 16.7%, p=0.04) among the ED-intervention sites, whereas the rate remained unchanged in ED-control sites (35.3% to 35.9%, p=0.9).
Implementation of a quality improvement intervention consisting of a reminder and decision-support tool increased initiation of OAC in high-risk patients. This support package can be readily implemented in other jurisdictions to improve OAC rates for AF/AFL.
Taphonomic factors may significantly alter faunal assemblages at varying scales. An exceptional record of late Holocene (<4000 yr old) mammal faunas establishes a firm baseline to investigate the effects of scale on taphonomy. Our sample contains 73 sites within four contiguous states (North Dakota, South Dakota, Iowa, and Illinois, USA) that transect a strong modern and late Holocene environmental gradient, the prairie–forest ecotone. We performed detrended correspondence (DCA) and non-metric multidimensional scaling (NMDS) analyses. Both DCA and NMDS analyses of the data sets produced virtually the same results, and both failed to reveal the known ecological gradient within each state. However, both DCA and NMDS analyses of the unfiltered multistate data set across the entire gradient clearly reflect an environmental, rather than taphonomic, signal. DCA tended to provide better separation of some clusters than did NMDS in most of the analyses. We conclude that a robust mammal data set collected across a strong environmental gradient will document species turnover without the removal of taphonomic factors. In other words, taphonomy exhibits varying scale-dependent effects.
The Neotoma Paleoecology Database is a community-curated data resource that supports interdisciplinary global change research by enabling broad-scale studies of taxon and community diversity, distributions, and dynamics during the large environmental changes of the past. By consolidating many kinds of data into a common repository, Neotoma lowers costs of paleodata management, makes paleoecological data openly available, and offers a high-quality, curated resource. Neotoma’s distributed scientific governance model is flexible and scalable, with many open pathways for participation by new members, data contributors, stewards, and research communities. The Neotoma data model supports, or can be extended to support, any kind of paleoecological or paleoenvironmental data from sedimentary archives. Data additions to Neotoma are growing and now include >3.8 million observations, >17,000 datasets, and >9200 sites. Dataset types currently include fossil pollen, vertebrates, diatoms, ostracodes, macroinvertebrates, plant macrofossils, insects, testate amoebae, geochronological data, and the recently added organic biomarkers, stable isotopes, and specimen-level data. Multiple avenues exist to obtain Neotoma data, including the Explorer map-based interface, an application programming interface, the neotoma R package, and digital object identifiers. As the volume and variety of scientific data grow, community-curated data resources such as Neotoma have become foundational infrastructure for big data science.
Late Quaternary small mammal faunas document ecological change and biotic responses to past climates but are especially rare in some geographic regions such as the North American Great Plains. Don’s Gooseberry Pit (DGP), a cave in the southeastern Black Hills of South Dakota, USA, contains a fauna documenting small mammal community composition shifts and environmental change over the last 18,000 yr in this data-depauperate region. Although the stratigraphy of the cave appears to be primary, disparate radiocarbon dates indicate that there is mixing of the fauna throughout. A paleoenvironmental signal consistent with regional reconstructions still emerges from an analysis of the stratigraphically ordered fauna. Dated taxa from DGP record the ecological replacement of Dicrostonyx by Myodes and later Microtus in response to late Quaternary warming. Individually dated specimens of Dicrostonyx richardsoni confirm late survival of this cold-adapted taxon in the Black Hills (17,083 cal yr BP). Our results indicate that a coarse paleoecological signal is present in DGP, and that the Black Hills served as a “high-altitude” refugium for cold-adapted species following the end of the last glacial period.
It has been an underlying assumption in many studies that near-surface layers imaged by ground-penetrating radar (GPR) can be interpreted as depositional markers or isochrones. It has been shown that GPR layers can be approximately reproduced from the measured electrical properties of ice, but these material layers are generally narrower and more closely spaced than can be resolved by typical GPR systems operating in the range 50−400 MHz. Thus GPR layers should be interpreted as interference patterns produced from closely spaced and potentially discontinuous material layers, and should not be assumed to be interpretable as precise markers of isochrones. We present 100 MHz GPR data from Lyddan Ice Rise, Antarctica, in which near-surface (<50 m deep) layers are clearly imaged. The growth of the undulations in these layers with depth is approximately linear, implying that, rather than resulting from a pattern of vertical strain rate, they do correspond to some pattern of snowfall variation. Furthermore, comparison of the GPR layers with snow-stake measurements suggests that around 80% of the rms variability in mean annual accumulation is present in the GPR layers. The observations suggest that, at least in this case, the GPR layers do approximate isochrones, and that patterns of snow accumulation over Lyddan Ice Rise are dominated by extremely persistent spatial variations with only a small residual spatial variability. If this condition is shown to be widely applicable it may reduce the period required for measurements of surface elevation change to be taken as significant indications of mass imbalance.
The late Quaternary was a time of rapid environmental fluctuations. The last glacial maximum was reached about 20 ka with continental glaciers covering most of Canada as well as the northeastern and upper midwestern United States (U.S.). Glacial ice physically displaced entire terrestrial biomes and the cooler climates altered distributions of species outside of the glacial limits. About 14 ka, the climate began to warm rapidly and glacial ice retreated northward, opening new landscapes for colonization by terrestrial biotas. Maximum warmth was reached between 9–5 ka with a time transgressive progression from west to east.
Radiocarbon chronologies allow for fine scale (100's to 1000's of years) resolution of mammal responses to these changes. Mammal communities did not respond as intact units but individual species shifted diachronically along environmental gradients. As a result, many late Pleistocene mammal communities contain associations of extant species that do not occur together today and appear to be ecologically incompatible. Pleistocene mammal communities also had a greater diversity of species than either Holocene or modern ones. This greater diversity was, in part, due to the existence of a diverse megafauna that became extinct at the end of the Pleistocene (10 ka). However, Pleistocene small mammal guilds with extant species, especially insectivores and microtine rodents, were also more diverse. Rapid changes in small mammal species distributions, diversity patterns, and clinal shifts around 10 ka strengthens environmental models for the end-Pleistocene extinction.
Modern mammal communities began to appear at the end of the Pleistocene and into the Holocene. In the eastern U.S., the species composition of these communities has been stable for the last 10 ka, although vegetational communities have shown change throughout the Holocene. In other parts of the U.S., middle Holocene warming caused some species to shift their geographic ranges. However, species composition of communities was not significantly altered. Understanding these changes not only provides a better perspective for viewing mammal communities of the past but it may also give insight into those of the future as climate will continue to vacillate, whether induced naturally or anthropogenically.
The terrestrial vertebrate fossil record provides a window into the past evolution of taxa, communities, and ecosystems. It can also be used to reconstruct ancient environments, climates, and landscapes. Vertebrate fossils can document the evolution of humans and their interactions with fauna and environments. However, before the maximum potential of this record can be realized, it is essential to know the extent of temporal resolution, or time-averaging, represented by fossil samples.
We have undertaken an adaptive optics imaging survey of extra-solar planetary systems and stars showing interesting radial velocity trends from high precision radial velocity searches. Adaptive Optics increases the resolution and dynamic range of an image, substantially improving the detectability of faint close companions. This survey is sensitive to objects less luminous than the bottom of the main sequence at separations as close as 1″. We have detected stellar companions to the planet bearing stars HD 114762 and Tau Boo. We have also detected a companion to the non-planet bearing star 16 Cyg A.
Small mammal species distribution, density, and composition of modern and Pleistocene faunas from the eastern United States provide information about environmental gradients. Higher summer temperatures and less effective moisture along a transect from the northeast to the southwest can be correlated with the distribution of small mammals as well as decreases in the total number of shrew and vole species. Relative frequencies of “boreal”, “deciduous”, and “steppe” species are more equal in late Wisconsin than modern faunas which are predominantly composed of only one group. A higher vole species density is prevalent in each late Wisconsin fauna and eleven of twelve of these faunas have a higher shrew species density than the corresponding modern fauna. Many shrew and vole species that are today endemic to the boreal provinces were cosmopolitan during the late Wisconsin. Moderate environmental gradients of the equable late Wisconsin climates allowed integration of boreal species with resident species in the south.
Survey data indicated that parents (notably mothers) regarded their own parents and partners as the most important sources of parenting information. Respondents were not at all likely to use parenting courses in a preventative sense, that is, to use courses in an attempt to anticipate problems before they occur and consider ways of dealing with them. Parents reported that they would be more likely to attend parenting courses once difficulties had become established. There was a preference for any parenting courses to consist of one-off sessions on particular topics rather than longer courses. Drugs and teenagers’ was the topic most frequently rated as ‘Very important’ for a parenting course. When presented with hypothetical problem situations, parents showed a preference for solving such problems within the family rather than consulting professionals. Parenting courses were not frequently seen as a solution to such problems. Reason for these perceptions are discussed. It seems that the ways in which parenting courses are described (advertised) may be crucial to their acceptance by parents who might benefit from them.
More than 300 coots (Fulica americana) became frozen in Spring Lake, Tazewell County, Illinois, on December 1, 1985. This catastrophic event permitted 8 weeks of taphonomic observations, which showed that ice forms a stable substrate which permits terrestrial taphonomic processes to be imprinted on lacustrine deposits. Bird and mammal scavengers attacked coot carcasses in different manners, resulting in distinct disarticulation sequences. Bird scavengers preferentially fed on the head, neck, and breast-wing complex, causing early disarticulation of bones in these areas, late loss of hindlimb joints, and minimal bone damage. In contrast, mammal scavengers concentrated their attention on the hindlimb and tail region, resulting in bone breakage and early disarticulation of these body parts, but late disarticulation of the breast-wing complex. These data demonstrate that scavenger-specific feeding behaviors significantly influence disarticulation patterns early in assemblage formation, while anatomy may exert increasingly greater influence on disarticulation patterns as carasses become less attractive to scavengers. Finally, because taphonomic processes change in intensity and type through time, bone frequency and modification patterns will vary according to the time at which the patterns are arrested by burial. Thus, bone frequency and modification patterns should provide an index to the relative importance of specific biotic agents and of anatomy in fossil disarticulation patterns as well as an estimate of the time between death and burial.
Dietary strategies for alleviating health complications associated with type 2 diabetes (T2D) are being pursued as alternatives to pharmaceutical interventions. Berries such as bilberries (Vaccinium myrtillus L.) that are rich in polyphenols may influence carbohydrate digestion and absorption and thus postprandial glycaemia. In addition, berries have been reported to alter incretins as well as to have antioxidant and anti-inflammatory properties that may also affect postprandial glycaemia. The present study investigated the acute effect of a standardised bilberry extract on glucose metabolism in T2D. Male volunteers with T2D (n 8; BMI 30 (sd 4) kg/m2) controlling their diabetes by diet and lifestyle alone were given a single oral capsule of either 0·47 g standardised bilberry extract (36 % (w/w) anthocyanins) which equates to about 50 g of fresh bilberries or placebo followed by a polysaccharide drink (equivalent to 75 g glucose) in a double-blinded cross-over intervention with a 2-week washout period. The ingestion of the bilberry extract resulted in a significant decrease in the incremental AUC for both glucose (P = 0·003) and insulin (P = 0·03) compared with the placebo. There was no change in the gut (glucagon-like peptide-1, gastric inhibitory polypeptide), pancreatic (glucagon, amylin) or anti-inflammatory (monocyte chemotactic protein-1) peptides. In addition there was no change in the antioxidant (Trolox equivalent antioxidant capacity, ferric-reducing ability of plasma) responses measured between the volunteers receiving the bilberry extract and the placebo. In conclusion the present study demonstrates for the first time that the ingestion of a concentrated bilberry extract reduces postprandial glycaemia and insulin in volunteers with T2D. The most likely mechanism for the lower glycaemic response involves reduced rates of carbohydrate digestion and/or absorption.
Digital signal processing is one of many valuable tools for suppressing unwanted signals or inter-ference. Building hardware processing engines seems to be the way to best implement some classes of interference suppression but is, unfortunately, expensive and time-consuming, especially if several miti-gation techniques need to be compared. Simulations can be useful, but are not a substitute for real data. CSIRO’s Australia Telescope National Facility has recently commenced a ‘software radio telescope’ project designed to fill the gap between dedicated hardware processors and pure simulation. In this approach, real telescope data are recorded coherently, then processed offline. This paper summarises the current contents of a freely available database of base band recorded data that can be used to experiment with signal processing solutions. It includes data from the following systems: single dish, multi-feed receiver; single dish with reference antenna; and an array of six 22 m antennas with and without a reference antenna. Astronomical sources such as OH masers, pulsars and continuum sources subject to interfering signals were recorded. The interfering signals include signals from the US Global Positioning System (GPS) and its Russian equivalent (GLONASS), television, microwave links, a low-Earth-orbit satellite, various other transmitters, and signals leaking from local telescope systems with fast clocks. The data are available on compact disk, allowing use in general purpose computers or as input to laboratory hardware prototypes.
As it was originally proposed, the extended phenotype comprised ‘all effects of a gene upon the world’ (Dawkins, 1989) and portrayed how the effects of a gene borne by an organism influenced its biotic and abiotic environments. The consideration of indirect genetic effects, in which an organism’s phenotype becomes part of the selective environment of conspecifics (Wolf et al., 1998), was developed rigorously in the population genetics context and the concept subsequently extended to include effects on heterospecifics (Whitham et al., 2003). The extended phenotype concept has been adopted as a framework by some evolutionary biologists and ecologists to study the roles of plant secondary metabolites (PSMs) since Whitham et al. (2003) used heritable variation in tissue tannin concentrations among Populus species and hybrids to develop the concept of community and ecosystem genetics (Antonovics, 1992).
Many studies of how genetically determined variation in plant traits, including PSMs, drive associated community phenotypes and processes, have been based on differences between hybrids (Dungey et al., 2000; Hochwender & Fritz, 2004; Bailey et al., Chapter 14). Fewer studies have investigated the effects on extended phenotypes of continuously varying PSMs or between known genotypes within a species (Whitham et al., 2006; Schweitzer et al., 2008; Barbour et al., 2009; O’Reilly-Wapstra et al., Chapter 2). A convenient approach to identification and utilisation of genotypic variation for the study of multiple effects of PSMs is provided by the use of genetic polymorphisms. A polymorphism can be defined as occurring when a trait such as a morphological or biochemical character exists in two or more distinct forms in a randomly mating population within a species (Ford, 1975). The approach is particularly useful in species that cannot be readily cloned. Here, we review examples of how intra-specific variation in a particular group of PSMs, the monoterpenes, has informed our understanding of how PSMs can play multiple ecological roles and mediate the extended phenotype of plants. The monoterpenes are a group of low-molecular-weight, volatile terpenoids which form a very diverse group in terms of number of compounds, structure and function (Gershenzon & Dudareva, 2007). We use variation within species which are polymorphic for concentrations or presence of monoterpenes to provide an insight into their ecological ramifications and larger-scale consequences, against the background of intra-specific variation in other traits.
The formal commissioning of the IRWG occurred at the 1991 Buenos Aires General Assembly, following a Joint Commission meeting at the IAU GA in Baltimore in 1988 that identified the problems with ground-based infrared photometry. The meeting justification, papers, and conclusions, can be found in Milone (1989). In summary, the challenges involved how to explain the failure to achieve the milli-magnitude precision expected of infrared photometry and an apparent 3% limit on system transformability. The proposed solution was to redefine the broadband Johnson system, the passbands of which had proven so unsatisfactory that over time effectively different systems proliferated, although bearing the same “JHKLMNQ” designations; the new system needed to be better positioned and centered in the spectral windows of the Earth's atmosphere, and the variable water vapour content of the atmosphere needed to be measured in real time to better correct for atmospheric extinction.
Two detailed sections through 4 km of distal alluvium of the Upper Devonian Old Red Sandstone in the Munster Basin, southern Ireland, display a limited number of lithofacies. There is little ordering of these lithofacies on a small scale but changes in the proportions of lithofacies through time define a sequence of stages of basin evolution. The depositional environments changed progressively from sheetflood dominant, via mobile ephemeral channels and floodplains to a more fixed channel–overbank system and eventually to a coastal plain. On the basis of the sedimentary record a progressive reduction in subsidence rate with time is deduced as the main control on the evolution of the basin fill. This deduction is consistent with predictions from previously applied extensional basin models, but is insufficiently refined at present to distinguish between the different models.