32,914 research outputs found

    How the global structure of protein interaction networks evolves

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    Two processes can influence the evolution of protein interaction networks: addition and elimination of interactions between proteins, and gene duplications increasing the number of proteins and interactions. The rates of these processes can be estimated from available Saccharomyces cerevisiae genome data and are sufficiently high to affect network structure on short time scales. For instance, more than 100 interactions may be added to the yeast network every million years, a substantial fraction of which adds previously unconnected proteins to the network. Highly connected proteins show a greater rate of interaction turnover than proteins with few interactions. From these observations one can explain ? without natural selection on global network structure ? the evolutionary sustenance of the most prominent network feature, the distribution of the frequency P(d) of proteins with d neighbors, which is a broad-tailed distribution. This distribution is independent of the experimental approach providing nformation on network structure

    State Bills of Rights : A Case of Neglect and the Need for a Renaissance

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    Quaternary warping at Gorge Saddle, western Southland

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    Gorge Saddle is one low point on a drainage divide between Fiordland and the Southland Plain. Eastward sloping Quaternary terraces east of the divide and westward sloping terraces to the west contain granitic pebbles which could have been derived only from the west. This suggests doming at the present divide concurrent with transport from the west

    HELIN Consortium OPAC Report

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    Report of the HELIN OPAC Task Force, a group appointed by the HELIN Directors to review the Innovative Interfaces online public access catalog under 2006 release driven by WebPAC Pro. The task force met during the fall of 2006

    HELIN Federated Search Task Force Final Report

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    Final report of the HELIN Federated Search Task Force, a group appointed by the HELIN Reference Committee at the request of the HELIN Directors to investigate and report on available federated search engines, which allow users simultaneously to search multiple databases. The task force was not asked to recommend a specific one for licensing by HELIN member libraries and did not do so

    Calculation of secondary electron trajectories in multistage depressed collectors for microwave amplifiers

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    Computational procedures are reported for treating power losses due to secondary electrons in multistage depressed collectors (MDC) for traveling wave tubes (TWT) and other O-type electron tubes. The MDC is modeled with an advanced, multidimensional computer program. Representative beams of secondary electrons are then injected at the points of impact of the primary beams. Separate programs are used to calculate representative beams of high-energy primary electron beams and of low-energy true secondaries. The recomputation of the MDC model including the true secondary beam allows determination of the secondary emission losses, and, if necessary, redesign of the MDC to improve performance. Recomputation of the MDC model including the primary beams is used to check on possible backstreaming from the MDC to the RF interaction structure of the tube. A comparison with experimentally measured values of TWT and MDC efficiencies is made

    HELIN Data Analytics Task Force Final Report

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    The main task undertaken by the HELIN Data Analytics Task Force was to conduct a proof-of-concept usability test of HELIN OneSearch, which is the Consortiumā€™s brand name for the Encore Duet discovery service. After the initial meeting in November 2014, the Task Force met 6 times in 2015 to plan and execute a prototype test. Staff members from EBSCO Information Servicesā€™ User Research group acted as usability test advisers and coordinators and attended all meetings, either onsite or via WebEx. Task Force members collaborated to come up with specific scenarios and personas which would best emphasize patron likes, dislikes and general understanding of OneSearch. Using a small sample of volunteer student test subjects from 3 different HELIN institutions, testing took place in mid-April. The results were analyzed by EBSCO and presented at the final meeting of the Task Force on April 28. Based on this limited testing, general findings were as follows: Students who donā€™t receive prior information instruction are generally not aware of OneSearch. Students who do know about OneSearch do not necessarily understand the difference between OneSearch and the HELIN Catalog. Most students still continue to do their research by searching database lists, LibGuides, the Journal A to Z list, and the HELIN catalog (although not necessarily in that order). When features and operation of OneSearch are explained to students, they recognize its usefulness (especially facets, which many referred to as ā€œfiltersā€). Lack of clarity on how to get directly to full text items causes frustration. A larger and more comprehensive usability test would be needed to draw out more specific conclusions. Secondary tasks undertaken by the Task Force included trials and reviews of 5 data analysis tools, as well as a review of EBSCO User Research, which is quantitative data on the use of OneSearch available directly from EBSCO. The remainder of this document is a detailed account of the proceedings of the HELIN Data Analytics Task Force

    HELIN Task Force on Electronic Archiving Report

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    Report of the HELIN Electronic Archiving Task Force, appointed from the HELIN Serials Committee and the HELIN Collection Development Committee

    HELIN Task Force on Licensing Agreements Final Report, 2/28/2010

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    Final report of the HELIN Task Force on Licensing Agreements to Robert Aspri, Executive Director of the HELIN Library Consortium, a group eminating from the HELIN Reference Committee, to investigate the issue of consortial licensing agreements for electronic books
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