177,046 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
Estimation of interdomain flexibility of N-terminus of factor H using residual dipolar couplings
No full textCharacterization of segmental flexibility is needed to understand the biological mechanisms of the very large category of functionally diverse proteins, exemplified by the regulators of complement activation, that consist of numerous compact modules or domains linked by short, potentially flexible, sequences of amino acid residues. The use of NMR-derived residual dipolar couplings (RDCs), in magnetically aligned media, to evaluate interdomain motion is established but only for two-domain proteins. We focused on the three N-terminal domains (called CCPs or SCRs) of the important complement regulator, human factor H (i.e., FH1-3). These domains cooperate to facilitate cleavage of the key complement activation-specific protein fragment, C3b, forming iC3b that no longer participates in the complement cascade. We refined a three-dimensional solution structure of recombinant FH1-3 based on nuclear Overhauser effects and RDCs. We then employed a rudimentary series of RDC data sets, collected in media containing magnetically aligned bicelles (disklike particles formed from phospholipids) under three different conditions, to estimate interdomain motions. This circumvents a requirement of previous approaches for technically difficult collection of five independent RDC data sets. More than 80% of conformers of this predominantly extended three-domain molecule exhibit flexions of <40°. Such segmental flexibility (together with the local dynamics of the hypervariable loop within domain 3) could facilitate recognition of C3b via initial anchoring and eventual reorganization of modules to the conformation captured in the previously solved crystal structure of a C3b:FH1-4 complex.</p
"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.
The NMR solution structure of the pheromone Er-2 from the ciliated protozoan Euplotes raikovi
No full textGoing 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
Adsorption of pure carbon dioxide and methane on dry coal from Sulcis coal Province (SW Sardinia, Italy).
No full textWhen coal seams are formed by compaction of plants, gases including methane are generated and accumulated into the coal cleats or adsorbed into the coal micropores. Such coalbed methane is normally recovered by means of reservoir-pressure depletion, i.e. by pumping out water and degassing the reservoir. A more attractive process with higher yields is the so-called Enhanced Coal Bed Methane recovery (ECBM), whereby carbon dioxide is pumped into the coal seam to displace methane thanks to higher CO2 adsorptivity. Injecting CO2 in unminable coal seams leads not only to methane recovery but also to CO2 sequestration. The factors still limiting the implementation of ECBM recovery are economical, i.e. lack of penalties for CO2 emissions, as well as technological and scientific, i.e. limited understanding of fundamental issues related to ECBM. Therefore, the goal of this study is to combine experimental measurements and modelling to characterize pure and multicomponent competitive adsorption of CO2 and CH4 on coal and study the coalbed dynamics using breakthrough experiments, including the effect of the injection of CO2 on matrix swelling and permeability. Since December 2004, a feasibility study throughout the Sulcis Coal Province in Sardinia [Quattrocchi, 2004] is in progress and one of its objectives is to correlate the results of the mentioned experiments with the compositional patterns of the coal, considering its role in the CBM-ECBM exploitation.Published355-3644.4. Scenari e mitigazione del rischio ambientaleJCR Journalreserve
Adsorption of pure carbon dioxide and methane on dry coal from Sulcis coal Province (SW Sardinia, Italy).
No full textWhen coal seams are formed by compaction of plants, gases including methane are generated and accumulated into the coal cleats or adsorbed into the coal micropores. Such coalbed methane is normally recovered by means of reservoir-pressure depletion, i.e. by pumping out water and degassing the reservoir. A more attractive process with higher yields is the so-called Enhanced Coal Bed Methane recovery (ECBM), whereby carbon dioxide is pumped into the coal seam to displace methane thanks to higher CO2 adsorptivity. Injecting CO2 in unminable coal seams leads not only to methane recovery but also to CO2 sequestration. The factors still limiting the implementation of ECBM recovery are economical, i.e. lack of penalties for CO2 emissions, as well as technological and scientific, i.e. limited understanding of fundamental issues related to ECBM. Therefore, the goal of this study is to combine experimental measurements and modelling to characterize pure and multicomponent competitive adsorption of CO2 and CH4 on coal and study the coalbed dynamics using breakthrough experiments, including the effect of the injection of CO2 on matrix swelling and permeability. Since December 2004, a feasibility study throughout the Sulcis Coal Province in Sardinia [Quattrocchi, 2004] is in progress and one of its objectives is to correlate the results of the mentioned experiments with the compositional patterns of the coal, considering its role in the CBM-ECBM exploitation.Published355-3644.4. Scenari e mitigazione del rischio ambientaleJCR Journalreserve
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
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
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