4,461 research outputs found
The Sarasota Dolphin Whistle Database : a unique long-term resource for understanding dolphin communication
Funding for data collection and analysis over the years has been provided by the National Science Foundation, The Royal Society of London, Dolphin Quest, Adelaide M. and Charles B. Link Foundation, Marine Mammal Commission, National Oceanic and Atmospheric Administration, Earthwatch Institute, Protect Wild Dolphins Fund of the Harbor Branch Oceanographic Institute, Grossman Family Foundation, WHOI Ocean Life Institute, Vulcan Machine Learning Center for Impact, and the Allen Institute for Artificial Intelligence. Current support for PT’s involvement is provided by the Office of Naval Research Grants N00014-18-1-2062 and N00014-20-1-2709 through a subaward from Carnegie Mellon University. Current support for LS’s involvement is provided by the Adelaide M. & Charles B. Link Foundation and Dolphin Quest.Common bottlenose dolphins (Tursiops truncatus) produce individually distinctive signature whistles that are learned early in life and that help animals recognize and maintain contact with conspecifics. Signature whistles are the predominant whistle type produced when animals are isolated from conspecifics. Health assessments of dolphins in Sarasota, Florida (USA) provide a unique opportunity to record signature whistles, as dolphins are briefly separated from conspecifics. Recordings were first made in the mid 1970’s, and then nearly annually since 1984. The Sarasota Dolphin Whistle Database (SDWD) now contains 926 recording sessions of 293 individual dolphins, most of known age, sex, and matrilineal relatedness. The longest time span over which an individual has been recorded is 43 years, and 85 individuals have been recorded over a decade or more. Here we describe insights about signature whistle structure revealed by this unique and expansive dataset. Signature whistles of different dolphins show great variety in their fundamental frequency contours. Signature whistle types (with ‘whistle type’ defined as all whistles visually categorized as sharing a particular frequency modulation pattern) can consist of a single stereotyped element, or loop (single-loop whistles), or of multiple stereotyped loops with or without gaps (multi-loop whistles). Multi-loop signature whistle types can also show extensive variation in both number and contour of loops. In addition, fundamental frequency contours of all signature whistle types can be truncated (deletions) or embellished (additions), and other features are also occasionally incorporated. However, even with these variable features, signature whistle types tend to be highly stereotyped and easily distinguishable due to the extensive variability in contours among individuals. In an effort to quantify this individual distinctiveness, and to compare it to other species, we calculated Beecher’s Information Statistic and found it to be higher than for any other animal signal studied so far. Thus, signature whistles have an unusually high capacity to convey information on individual identity. We briefly review the large range of research projects that the SDWD has enabled thus far, and look ahead to its potential to answer a broad suite of questions about dolphin communication.Publisher PDFPeer reviewe
An Automated System for Hydroxide Catalysis Bonding of Precision-Aligned Optical Systems
Precision-aligned, robust, ultra-stable optical assemblies are required in an increasing number of space-based applications such as fundamental science, metrology and geodesy. Hydroxide catalysis bonding is a proven, glue-free, technology for building such optical systems from materials such as ULE, Zerodur and fused silica. Hydroxide catalysis bonded optical systems have flown in missions such as GP-B and LISA Pathfinder achieving picometer path-length stability and microradian component stability over full mission lifetime. Component alignment and bonding was previously a largely manual process that required skilled operators and significant time. We have recently automated most of the alignment and bonding steps with the goals of improving overall precision, speed and reliability. Positioning and bonding of an optical component to within 4 microns and 10 microradians of a target position and alignment can now be reliably completed within half an hour, compared to the many hours typically taken previously. The key new features of this system are an interferometer that monitors the parallelism and separation of the surfaces to be bonded and a precision multi-axis manipulator that can optimise component alignment as it brings it down to the point of bonding. We present a description of the system and a summary of the alignment results obtained in a series of 9 test bonds. We also show how this system is being developed for integration into a precision optical manufacturing facility for assembly of large optical systems
A convolute diversity of the Auriculariales (Agaricomycetes, Basidiomycota) with sphaeropedunculate basidia
Morphological and DNA data show that effused representatives of the Auriculariales (Basidiomycota) with sphaeropedunculate basidia belong to eleven genera of which seven are dealt with in this study. Among them, Myxarium is the largest genus containing 21 accepted species of which nine are reintroduced below and five are described as new. Protodontia is limited to three species only, P. subgelatinosa (the generic type) and two newly described species from Africa. Protoacia is a new monotypic genus for P. delicata, sp. nov., widely distributed on coniferous hosts in Eurasia. Myxariellum is erected for two new species with smooth hymenophore from northwestern North America while Gelacantha is introduced for G. pura, a new species with hydnoid hymenophore from Caucasus. Our data do not confirm the present synonymy of Sebacina sphaerospora with Tremella glaira, and these species are placed in two separate genera - Hydrophana, gen. nov., and Ofella, gen. nov., respectively. A key to European Myxarium and similar-looking species is included.Peer reviewe
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Erratum: Author Correction: Identification of genes required for eye development by high-throughput screening of mouse knockouts.
[This corrects the article DOI: 10.1038/s42003-018-0226-0.]
The SHARP study: a quantitative and qualitative evaluation of the short-term outcomes of housing and neighbourhood renewal
<p><b>Background:</b> The SHARP study was set up to evaluate the short (1 year) and longer-term (2 year) effects on health and wellbeing of providing new social housing to tenants. This paper presents the study background, the design and methods, and the findings at one year.</p>
<p><b>Methods:</b> Data were collected from social tenants who were rehoused into a new, general-purpose socially-rented home developed and let by a Scottish Registered Social Landlord (the "Intervention" group). These data were collected at three points in time: before moving (Wave 1), one year after moving (Wave 2) and two years after moving (Wave 3). Data were collected from a Comparison group using the same methods at Baseline (Wave 1) and after two years of follow-up (Wave 3). Qualitative data were also collected by means of individual interviews. This paper presents the quantitative and qualitative findings at 1 year (after Wave 2).</p>
<p><b>Results:</b> 339 Intervention group interviews and 392 Comparison group interviews were completed. One year after moving to a new home there was a significant reduction in the proportion of Intervention group respondents reporting problems with the home, such as damp and noise. There was also a significant increase in neighbourhood satisfaction compared with Baseline (χ2 = 35.51, p < 0.0001). Many aspects of the neighbourhood improved significantly, including antisocial behaviour. In terms of environmental aspects and services the greatest improvements were in the general appearance of the area, the reputation of the area, litter and rubbish, and speeding traffic. However, lack of facilities for children/young people and lack of safe children's play areas remained a concern for tenants.</p>
<p><b>Conclusion:</b> This study found that self-reported health changed little in the first year after moving. Nonetheless, the quantitative and qualitative data point to improvements in the quality of housing and of the local environment, as well as in tenant satisfaction and other related outcomes. Further analyses will explore whether these effects are sustained, and whether differences in health outcomes emerge at 2 years compared with the Comparison group.</p>
Measurements of Flavour Dependent Fragmentation Functions in Z^0 -> qq(bar) Events
Fragmentation functions for charged particles in Z -> qq(bar) events have
been measured for bottom (b), charm (c) and light (uds) quarks as well as for
all flavours together. The results are based on data recorded between 1990 and
1995 using the OPAL detector at LEP. Event samples with different flavour
compositions were formed using reconstructed D* mesons and secondary vertices.
The \xi_p = ln(1/x_E) distributions and the position of their maxima \xi_max
are also presented separately for uds, c and b quark events. The fragmentation
function for b quarks is significantly softer than for uds quarks.Comment: 29 pages, LaTeX, 5 eps figures (and colour figs) included, submitted
to Eur. Phys. J.
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