196,060 research outputs found
Long-range pair potential from the low density S(k) of 4He around 6 K
No full textThe static structure factor S(k) of gaseous 4He at various densities along the T=6.13 K isotherm has been determined with the G4.1 diffractometer at LLB (Saclay, F). Thanks to the explored k-values (1<k/nm^-1<34), the long range behaviour of the interatomic interaction potential U(r^N) can be conveniently investigated. The resulting structure factors S(k) are presented and compared with previous determinations obtained at almost the same thermodynamic conditions using the D4B and D11 diffractometers at ILL (Grenoble, F). By means of a well known low-k expansion of the Fourier transform of the direct correlation function c(k), the London dispersion coefficient C6 of the r^-6 tail in U(r^N) has been experimentally evaluated for the first time and compared with the values present in literature
EQUATION OF STATE OF URANIUM OXIDE: MACH-DISK INVESTIGATION OF TRANSIENT LASER-INDUCED VAPORIZATION OF UO//2 UP TO 5000 K.
No full textA theoretical analysis of the gas dynamics of the Mach-disk technique in laser evaporation experiments is presented. The relation between stagnation pressure, sonic pressure, and saturation pressure is given, and the equivalent sonic orifice diameter for laser-induced vaporization is calculated. Experimental results on UO//2, which make use of the results of this analysis, are presented. These measurements, in the temperature range 3700-4200 K, confirm previous data for the total vapor pressure. The vaporization mechanism at extreme rates of evaporation and the relevance of equilibrium calculations to high-temperature evaporating systems are also discussed. Refs
Depolarization and decreased surface expression of K+ channels contribute to NSAID-inhibition of intestinal restitution
No full textNon-steroidal anti-inflammatory drugs (NSAIDs) contribute to gastrointestinal ulcer formation by inhibiting epithelial cell migration and mucosal restitution; however, the drug-affected signaling pathways are poorly defined. We investigated whether NSAID inhibition of intestinal epithelial migration is associated with depletion of intracellular polyamines, depolarization of membrane potential (Em) and altered surface expression of K+ channels. Epithelial cell migration in response to the wounding of confluent IEC-6 and IEC-Cdx2 monolayers was reduced by indomethacin (100μM), phenylbutazone (100μM) and NS-398 (100μM) but not by SC-560 (1μM). NSAID-inhibition of intestinal cell migration was not associated with depletion of intracellular polyamines. Treatment of IEC-6 and IEC-Cdx2 cells with indomethacin, phenylbutazone and NS-398 induced significant depolarization of Em, whereas treatment with SC-560 had no effect on Em. The Em of IEC-Cdx2 cells was: −38.5±1.8mV under control conditions; −35.9±1.6mV after treatment with SC-560; −18.8±1.2mV after treatment with indomethacin; and −23.7±1.4mV after treatment with NS-398. Whereas SC-560 had no significant effects on the total cellular expression of Kv1.4 channel protein, indomethacin and NS-398 decreased not only the total cellular expression of Kv1.4, but also the cell surface expression of both Kv1.4 and Kv1.6 channel subunits in IEC-Cdx2. Both Kv1.4 and Kv1.6 channel proteins were immunoprecipitated by Kv1.4 antibody from IEC-Cdx2 lysates, indicating that these subunits co-assemble to form heteromeric Kv channels. These results suggest that NSAID inhibition of epithelial cell migration is independent of polyamine-depletion, and is associated with depolarization of Em and decreased surface expression of heteromeric Kv1 channels.ID: S0006295207001931; M3: Article; Accession Number: S0006295207001931; Author: L.C. Freeman (b); Author: D.F. Narvaez (a); Author: A. McCoy (a); Author: F.B. von Stein (c); Author: S. Young (b); Author: K. Silver (a); Author: S. Ganta (b); Author: D. Koch (b); Author: R. Hunter (b); Author: R.F. Gilmour (c); Author: J.D. Lillich (a, ⁎); Affiliation: Department of Clinical Sciences, Kansas State University, Manhattan, KS 66506, United States; Affiliation: Department of Anatomy and Physiology, Kansas State University, Manhattan, KS 66506, United States; Affiliation: Department of Biomedical Sciences, Cornell University, Ithaca, NY 14853, United States; Keyword: Non-steroidal anti-inflammatory drugs; Keyword: Intestinal epithelial cells; Keyword: Membrane potential; Keyword: Potassium channels; Number of Pages: 12; Language: English;Source type: Electronic(1)http://search.ebscohost.com/login.aspx?direct=true&db=edselp&AN=S0006295207001931&site=eds-live&scope=sit
Low-thrust propulsion technologies for space mission applications
No full textIn this thesis, various aspects of physical modeling are developed to suggest the possibility that alternative low-thrust propulsion systems could be concretely employed in mission scenarios made attractive by recent developments in astrobiology. The systems considered are a solar sail using the additional contribute of thermal desorptiona and the Direct Fusion Drive (DFD) engine. The specific aspects developed in this thesis are the use of evaporable materials to increase the thrust in solar sails, the modeling of the transport of charged particles in magnetized plasmas such as those of interest for compact fusion reactors, and the simulation of specific mission scenarios. The methods used for this purpose are based on the kinetic theory of gases and plasma and on flight dynamics. The results obtained, in addition to the first integrated exposure of these two propulsion systems within specific scenarios, are: the study of the effect of evaporable material, the development of a high-performance computing program for the simulation of the dynamics of charged particles in magnetized plasmas, the detailed simulation of a scenario for reaching promising targets for deep space exploration
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
Measurement of the ratio of branching fractions B(B0→K∗0γ )/B(B0s→φγ ) and the directCP asymmetry inB 0→K∗0γ
No full textThe ratio of branching fractions of the radiative B decays B0→K⁎0γ and B0s→ϕγ has been measured using an integrated luminosity of 1.0 fb−1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of s√=7TeV. The value obtained is
B(B0→K⁎0γ)B(B0s→ϕγ)=1.23±0.06(stat.)±0.04(syst.)±0.10(fs/fd),
where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for B(B0→K⁎0γ), the branching fraction B(B0s→ϕγ) is measured to be (3.5±0.4)×10−5.
The direct CP asymmetry in B0→K⁎0γ decays has also been measured with the same data and found to be
ACP(B0→K⁎0γ)=(0.8±1.7(stat.)±0.9(syst.))%.
Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations
Correction to: Bican, R., Christensen, C., Fallieras, K., Sagester, G., O’Rourke, S., Byars, M., & Tanner, K. (2021). Rapid Implementation of Telerehabilitation for Pediatric Patients During COVID-19
No full textCorrection to: Bican, R., Christensen, C., Fallieras, K., Sagester, G., O’Rourke, S., Byars, M., & Tanner, K. (2021). Rapid Implementation of Telerehabilitation for Pediatric Patients During COVID-19. International Journal of Telerehabilitation, 13(1). https://doi.org/10.5195/ijt.2021.6371
The affiliation for each author was incorrectly stated as: Physical Medicine & Rehabilitation, Children’s Minnesota, Minneapolis, Minnesota, USA
The correct affiliation for each author is: Clinical Therapies, Nationwide Children’s Hospital, Columbus, Ohio, USA
The metadata for the original article has been corrected
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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