975 research outputs found
Detecting LISA sources using time-frequency techniques
The planned Laser Interferometer Space Antenna (LISA) will detect
gravitational wave signals from a wide range of sources. However, disentangling
individual signals from the source-dominated data stream is a challenging
problem and the focus of much current research. The problems are particularly
acute for detection of extreme mass ratio inspirals (EMRIs), for which the
instantaneous signal amplitude is an order of magnitude below the level of the
instrumental noise, and the parameter space of possible signals is too large to
permit fully-coherent matched filtering. One possible approach is to attempt to
identify sources in a time-frequency spectrogram of the LISA data. This is a
computationally cheap method that may be useful as a first stage in a
hierarchical analysis. Initial results, evaluated using a significantly
simplified model of the LISA data stream, suggest that time-frequency
techniques might be able to detect the nearest few tens of EMRI events. In this
proceedings article, we briefly outline the methods that have so far been
applied to the problem, initial results and possible future directions for the
research.Comment: 3 pages; to appear in Proceedings of the Eleventh Marcel Grossmann
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Stable isotope probing: Technical considerations when resolving ¹⁵N-labeled RNA in gradients
RNA based stable isotope probing (SIP) facilitates the detection and identification of active members of microbial populations that are involved in the assimilation of an isotopically labeled compound. ¹⁵N-RNA-SIP is a new method that has been discussed in recent literature but has not yet been tested. Herein, we define the limitations to using ¹⁵N-labeled substrates for SIP and propose modifications to compensate for some of these shortcomings. We have used ¹⁵N-RNA-SIP as a tool for analysing mixed bacterial populations that use nitrogen substrates. After incubating mixed microbial communities with ¹⁵N-ammonium chloride or ¹⁵N₂ we assessed the fractionation resolution of ¹⁵N-RNA by isopycnic centrifugation in caesium trifluoroacetate (CsTFA) gradients. We found that the more isotopic label incorporated, the further the buoyant density (BD) separation between ¹⁵N- and ¹⁴N-RNA, however it was not possible to resolve the labeled from unlabeled RNA definitively through gradient fractionation. Terminal-restriction fragment length polymorphism (T-RFLP) analysis of the extracted RNA and fluorescent in situ hybridisation (FISH) analysis of the enrichment cultures provided some insight into the organisms involved in nitrogen fixation. This approach is not without its limitations and will require further developments to assess its applicability to other nitrogen-fixing environments
Retrieval of similar travel routes using GPS tracklog place names
GPS tracklogs provide a valuable record of routes travelled. In this paper we describe initial experiments exploring the use of text information retrieval techniques for the location of similar trips from within a GPS tracklog. We performed the experiment on a dataset of 528 individual trips gathered over a seven month time period from a single user. The results of our preliminary study suggest that traditional text-based information retrieval techniques can indeed be used to locate similar and related tracklogs
Rule Modeling Using Semantic MediaWiki
Semantic MediaWiki (SMW) is a popular semantic wiki engine that enables collective knowledge modeling within the expressivity of a small subset of OWL. However, SMW is limited in offering native support for modeling rules. In this paper, we show that by using templates and semantic queries provided by SMW, it is possible to model several types of rules within SMW, e.g., OWL entailment rules and logic programs. Such modeling practice enables us to perform some broadly useful inference tasks on SMW, e.g., integrity constraint checking
A Controlled Natural Language Interface for Semantic Media Wiki
Despite their potential value as collaborative knowledge editing systems, semantic wikis present a number of usability challenges for human end users. In particular, there are several mismatches between the simple user interaction mechanisms of wikis (which are the key to the success of wikis) and the need for users to create, edit and understand structured knowledge content (e.g., in the form of RDF or OWL ontologies). In this paper, we present a Controlled Natural Language (CNL) approach to collaborative ontology development using Semantic MediaWiki (SMW). In order to support the expressivity required for OWL ontology development, we extended the representational substructure of the SMW system with an OWL meta model using a template-based mechanism. To improve usability, we provided a form-based guided input interface and implemented several CNL verbalizers (CNL text generation components). In particular, we developed verbalizers for the English and Chinese variants of the Rabbit CNL, as well as the Attempto Controlled English (ACE) CNL. The combination of semantic wiki systems and CNL editing interfaces may provide an effective mechanism for promoting the large-scale collaborative creation of semantically-enriched online content
Information access for personal media archives
It is now possible to archive much of our life experiences in digital form using a variety of sources, e.g. blogs written, tweets made, photographs taken, etc. Information can be captured from a myriad of personal information devices. In this workshop, researchers from diverse disciplines discussed how we can advance towards the goal of effective capture, retrieval and exploration of e-memories. Proposed solutions included advanced textile sensors to capture new data, P2P methods to store this data, and personal reflection applications to review this data. Much discussion centered around search and navigation strategies, interactive interfaces, and the cognitive basis in using digitally captured information as memorabilia
GIDS: Global Interlinked Data Store
This paper introduces the Global Interlinked Data Store1 (GIDS), a technique to support the easy creation and retrieval of interlinked semantic data within a web-scale distributed network environment such as the World Wide Web (WWW). The GIDS enables the network to be treated as a data store without worrying about files, databases or other traditional data storage concerns. Data created on the network can be subsequently accessed and navigated by end users and software agents alike. The GIDS proposes a novel three-stage data storage process which enables the data to be stored in up to three contextually relevant locations to enhance subsequent retrieval opportunities. We believe that the capability offered by the GIDS will be of significant use to rapidly formed diverse coalitions who wish to communicate and exchange semantic data in a large network environment such as the WWW
Data collection methods for task-based information access in molecular medicine
An important area of improving access to health information is the study of task-based information access in the health domain. This is a significant challenge towards developing focused information retrieval (IR) systems. Due to the complexities of this context, its study requires multiple and often tedious means of data collection, which yields a lot of data for analysis, but also allows triangulation so as to increase the reliability of the findings. In addition to traditional means of data collection, such as questionnaires, interviews and observation, there are novel opportunities provided by lifelogging technologies such as the SenseCam. Together they yield an understanding of information needs, the sources used, and their access strategies. The present paper examines the strengths and weaknesses of the traditional and the more novel means of data collection and addresses the challenges in their application in molecular medicine, which intensively uses digital information sources
Search for B0s oscillations using inclusive lepton events
A search for B0s oscillations is performed using a sample of semileptonic
b-hadron decays collected by the ALEPH experiment during 1991-1995. Compared to
previous inclusive lepton analyses, the proper time resolution and b-flavour
mistag rate are significantly improved. Additional sensitivity to B0s mixing is
obtained by identifying subsamples of events having a B0s purity which is
higher than the average for the whole data sample. Unbinned maximum likelihood
amplitude fits are performed to derive a lower limit of Deltam_s>9.5ps^-1 at
95% CL. Combining with the ALEPH D-s based analyses yields Deltam_s>9.6ps^-1 at
95% CL.Comment: 23 pages, 10 figure
Generating EQ-5D-5L health utility scores from BASDAI and BASFAI : A mapping study in patients with axial spondyloarthritis using longitudinal UK registry data
Acknowledgments: We are grateful to the staff of the British Society for Rheumatology Biologics Register in Axial Spondyloarthritis. Claudia Zabke, Maureen Heddle, Nafeesa Nazlee and Barry Morris, and to the recruiting staff at the clinical centres, details of which are available at: https://www.abdn.ac.uk/iahs/research/epidemiology/spondyloarthritis.php#panel1011 Funding/Support: The British Society for Rheumatology Biologics Register in Ankylosing. Spondylitis (BSRBR-AS) is funded by the British Society for Rheumatology (BSR), which in turn has received funding from the manufacturers of the biologic therapies included in the study (Abbvie, Pfizer and UCB). Pharmaceutical companies providing funds to BSR do not have a role in the oversight of the study, but they do receive advance notice of publications on which they can comment. They do not have access to the data collected but can request analyses of the data, for which additional funds are provided.Peer reviewedPostprin
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