177,390 research outputs found
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
ICEKp2: description of an integrative and conjugative element in Klebsiella pneumoniae, co-occurring and interacting with ICEKp1
No full textKlebsiella pneumoniae is a human pathogen, prominent in antimicrobial-resistant and nosocomial
infection. The integrative and conjugative element ICEKp1 is present in a third of clinical isolates and
more prevalent in invasive disease; it provides genetic diversity and enables the spread of virulenceassociated
genes. We report a second integrative conjugative element that can co-occur with ICEKp1
in K. pneumoniae. This element, ICEKp2, is similar to the Pseudomonas aeruginosa pathogenicity
island PAPI. We identified ICEKp2 in K. pneumoniae sequence types ST11, ST258 and ST512, which
are associated with carbapenem-resistant outbreaks in China and the US, including isolates with and
without ICEKp1. ICEKp2 was competent for excision, but self-mobilisation to recipient Escherichia
coli was not detected. In an isolate with both elements, ICEKp2 positively influenced the efficiency of
plasmid mobilisation driven by ICEKp1. We propose a putative mechanism, in which a Mob2 ATPase of
ICEKp2 may contribute to the ICEKp1 conjugation machinery. Supporting this mechanism, mob2, but
not a variant with mutations in the ATPase motif, restored transfer efficiency to an ICEKp2 knockout.
This is the first demonstration of the interaction between integrative and conjugative genetic elements
in a single Gram-negative bacterium with implications for understanding evolution by horizontal gene
transfer
"Closing the R&D Gap, Evaluating the Sources of R&D Spending"
No full textBoth spending and tax policies have been implemented in the United States with the goal of stimulating private sector research and development (R&D). Karier questions whether current R&D policy, especially the research and experimentation tax credit, can contribute to closing the gap between nondefense expenditures on R&D in the United States and such expenditures in other countries, such as Japan and Germany. He also explores possible changes to our current R&D policy to make it more effective.
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Rajakumar_Gowers_etal_supplementary – Supplemental material for Rapid Prototyping Platform for Saccharomyces cerevisiae Using Computer-Aided Genetic Design Enabled by Parallel Software and Workcell Platform Development
No full textSupplemental material, Rajakumar_Gowers_etal_supplementary for Rapid Prototyping Platform for Saccharomyces cerevisiae Using Computer-Aided Genetic Design Enabled by Parallel Software and Workcell Platform Development by P. D. Rajakumar, G-O. F. Gowers, L. Suckling, A. Foster, T. Ellis, R. I. Kitney, D. W. McClymont and P. S. Freemont in SLAS Technology</p
Letter from R. R. Zellick, Assistant Trust Officer, Anglo California National Bank of San Francisco, to Joseph R. Goodman, October 2, 1942
No full textLetter from R. R. Zellick, Assistant Trust Officer at The Anglo California National Bank of San Francisco, to Joseph R. Goodman, regarding property owned by Dave Tatsuno. Zellick mentions a dispute between current tenants and Tatsuno, and that Tatsuno has asked Goodman to help locate trustworthy tenants.Personal correspondence, organizational records, government documents, publications, and other papers created or collected by Joseph R. Goodman documenting the forced removal and incarceration of Japanese Americans during World War II, as well as organized resistance to incarceration. Included in the collection are records of the Japanese Young Men's Christian Association and the Japanese American Citizens' League in San Francisco, including papers of the Japanese YMCA's executive secretary Lincoln Kanai; Sakai family papers; Goodman's correspondence to and from Japanese American incarcerees, organizations opposing forced removal and incarceration of Japanese Americans, the War Relocation Authority, and others; publications, photographs, and ephemera from the Topaz Relocation Center, where Goodman taught high school; War Relocation Authority records and publications; and newspaper clippings, pamphlets, and reports about forced removal and incarceration created by various government, religious, and civic organizations, in California and nationwide
A Virulence Associated Siderophore Importer Reduces Antimicrobial Susceptibility of Klebsiella pneumoniae
No full textThe accessory genomes of many pathogenic bacteria include ABC transporters that scavenge metal by siderophore uptake and ABC transporters that contribute to antimicrobial resistance by multidrug efflux. There are mechanistic and recently recognized structural similarities between siderophore importer proteins and efflux pumps. Here we investigated the influence of siderophore importer YbtPQ on antimicrobial resistance of Klebsiella pneumoniae. YbtPQ is encoded in the yersiniabactin cluster in a prevalent mobile genetic element ICEKp, and is also common in pathogenicity islands of Escherichia coli and Yersinia species, where yersiniabactin enhances virulence. Deletion of ICEKp increased the susceptibility of K. pneumoniae to all antimicrobials tested. The mechanism was dependent on the yersiniabactin importer YbtPQ and may involve antimicrobial efflux, since it was affected by the inhibitor reserpine. The element ICEKp is naturally highly mobile, indeed the accessory genome of K. pneumoniae is recognized as a reservoir of genes for the emergence of hospital outbreak strains and for transfer to other Gram-negative pathogens. Introduction of ICEKp, or a plasmid encoding YbtPQ, to E. coli decreased its susceptibility to a broad range of antimicrobials. Thus a confirmed siderophore importer, on a rapidly evolving and highly mobile element capable of interspecies transfer, may have a secondary function exporting antimicrobials
Dispelling the Myths Behind First-author Citation Counts
No full textWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
Nexus of 6G and Blockchain for Authentication of Aerial and IoT Devices
No full textInternet of Things (IoT) is a system of interrelated sensors and computers to transfer data over a network. However, the sensors, Unmanned Aerial Vehicles (UAVs), and other IoT equipment used are susceptible to different security attacks. Dumb sensors are used to collect data in hostile environments. Dumb sensors are low powered sensors that lack computational power to perform cryptological operations. These sensors are preferred over high powered sensors due to their low electrical signature, but they have negligible computing power. To overcome the loss of authentication data due to node capture and lack of sensor location verification, we propose the Nexus of 6G and Blockchain for Authentication (NBA) system. The NBA system utilizes a permissioned blockchain-based network of UAVs and smart sensors to prevent code tampering. The system enables two-way trusted data transfer between UAVs and dumb sensors through a novel Hybrid Physical Unclonable Function Hashing (HPUFH) model. The system also utilizes a novel Pattern-based Signal Strength Correlation (PbSSC) algorithm to detect any unexpected location changes in the dumb sensor field. The extensive security and performance evaluation demonstrates that the proposed system is highly efficient and secure with a linear computational cost proportional to the number of challenge-response pairs
Supplementary Tables and Figures -Supplemental material for Associations Between the Features of Gross Placental Morphology and Birthweight
No full textSupplemental material, Supplementary Tables and Figures for Associations Between the Features of Gross Placental Morphology and Birthweight by Alexa A Freedman, Carol J Hogue, Carmen J Marsit, Augustine Rajakumar, Alicia K Smith, Robert L Goldenberg, Donald J Dudley, George R Saade, Robert M Silver, Karen J Gibbins, Barbara J Stoll, Radek Bukowski and Carolyn Drews-Botsch in Pediatric and Developmental Pathology</p
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