1,720,981 research outputs found
Feasibility study of IE-SASW Method for the Non-Destructive Evaluation of Containment Building of Nuclear Power plant
No full textThe IE-SASW method, a combination of impact-echo (IE) acoustics with spectral analysis of surface waves (SASW), is proposed as a newly developed nondestructive testing method in concrete structures. This feasibility study examines the IE technique and uses elastic P-wave velocity data as measured from the SASW method on concrete members in nuclear power plant containment structures. It was shown that both the thickness of the concrete specimens used in this study and the depth of the introduced defects (i.e. voids) could be identified by the IE-SASW method. In contrast, the reinforced steel bar itself could not be identified by the IE-SASW method. Additionally, GPR (ground penetrating radar) techniques were used to examine the same specimens in order to establish some level of performance and reliability to compare with the performance of the IE-SASW method. The GPR method provides an objective and reliable image corresponding to the reinforced steel bars. The experimental studies show that it is more feasible to use the IE-SASW method rather than GPR to detect voids that were positioned beneath the steel reinforcing bars in the concrete specimens. (C) 2002 Elsevier Science B.V. All rights reserved
Mechanical properties and structural stability of perovskite-type, oxygen-permeable, dense membranes
No full textMechanical properties are considered as critical factors for electrochemical applications of ion conducting oxides because chemically induced stresses can cause component degradation, and it also needs to reduce the thickness of conductors for higher performance. Mechanical properties and structural stability under a reducing environment of oxygen-permeable, dense membranes were investigated. The mechanical properties such as fracture strength and toughness of the membrane could be explained with microstructural features and relative density. Reasons for membrane failure occurring during an oxygen permeation experiment were discussed with viewpoints towards lattice parameter change caused by nonstoichiometry, phase instability under the reducing environment, and stresses induced by reactor configuration. Stress analysis and fractographical investigation were conducted to support the discussions. It was found that a Sr- and Fe-doped LaGaO3 membrane is reliable under a reducing environment at elevated temperature
TonEBP is inhibited by RNA helicase A via interaction involving the E ' F loop
No full textTonEBP [TonE (tonicity-responsive enhancer)-binding protein] is a transcriptional activator of the Rel family like NF-?? B (nuclear factor ?? B) and NFAT (nuclear factor of activated T-cells). TonEBP plays a key role in the protection of cells in the kidney medulla from the deleterious effects of hyperosmolality. This is achieved by enhancing expression of HSP70 (heat-shock protein 70) and other genes whose products drive cellular accumulation of organic osmolytes. TonEBP is stimulated by ambient hypertonicity via multiple pathways that regulate nuclear translocation and transactivation. In the present paper, we report that TonEBP is associated in vivo with RHA (RNA helicase A). The N- and C-termini of RHA bound the E???F loop of the DNA-binding domain of TonEBP. The interaction was not affected by DNA binding or dimerization of TonEBP. Overexpression of RHA inhibited the activity of TonEBP; however, catalytic activity of RHA was dispensable for the inhibition. When the ambient tonicity was raised, the TonEBP-RHA interaction decreased, suggesting that dissociation of RHA is a pathway to stimulate TonEBP. We conclude that the E???F loop of TonEBP interacts with RHA like NFAT and NF-?? B interact with AP1 (activator protein 1) and the high-mobility group protein HMG-I(Y) respectively. While RHA interacts with and stimulates other transcription factors such as CREB (cAMP-response-element-binding protein), NF-?? B and mineralocorticoid receptor, it inhibits TonEBP.close141
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
RNA helicase a modulates activity of TonEBP/NFAT5 transcriptional activator in hypertonicity.
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe 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
Oxygen-permeating property of LaSrBFeO3 (B=Co, Ga) perovskite membrane surface-modified by LaSrCoO3
No full textOxygen permeation fluxes have been investigated as a function of temperature for a mixed ionic-electronic conducting La0.6Sr0.4Co0.2Fe0.8O3 (- delta) (LSCF) and La0.7Sr0.3 Ga-0.6 Fe-0.4 O3 - delta (LSGF) membranes. Ga-doped composition, which is known for its chemical and structural stability, shows limited oxygen permeation flux as compared with a Co-containing system. However, modification of both surfaces with catalytically surface-reactive La0.6Sr0.4CoO3 - delta (LSC) makes Ga-doped perovskite an excellent oxygen-permeable membrane. It has been demonstrated that the effective area of reactive free surface is an important factor in determining the effectiveness of surface modification by La0.6Sr0.4CoO3 - delta On the contrary, the oxygen permeation flux of La0.6Sr0.4Co0.2Fe0.8O3 - delta is not affected by surface modification. The rate-determining process is discussed in conjunction with the apparent activation energy for oxygen permeation. As cationic substitution occurs in the vicinity of the interface between the coating layer and substrate membrane at elevated temperatures, the intermediate composition, that is, (La1-xSrx)(CoyGayFe1-y-y)O3-delta, has been formed in La0.7Sr0.3Ga0.6Fe0.4O3 (- delta) membrane surface-modified by La0.6Sr0.4CoO3 (-) delta. (C) 2002 Elsevier Science B.V. All rights reserved.This work is supported in part by a grant from the
Korea Ministry of Education (the Brain Korea 21
Program of KAIST). The authors thank Kyung Tae
Lim, Ji Haeng Yu and Kee Bae Park for their helpful
discussion and assistance with this work
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe 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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