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## ‣ A method for the measurement of the absolute value of w for X-rays in noble gases: results at 5.9 keV in xenon

Borges, F. I. G. M.; Conde, C. A. N.
Tipo: Artigo de Revista Científica
Português
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46.94545%
A method is described that allows the measurement of the absolute value of the average energy to produce an ion pair, w, in noble gases for soft X-rays and its energy dependence. It uses a specially designed gas proportional scintillation counter working under electric fields below the ionization threshold. The spectrum of the radiation absorbed, and so the number of photons detected at each energy for a period of time on the order of the minute, is measured with the scintillation counter and, at the same time, the total primary electron charge produced is collected in one of the grids and measured with an electrometer. For pure xenon at 1030 mbar, a value of w=24.2±2.5 eV is measured with 5.9-keV X-rays

## ‣ ON THE MINIMUM ABSOLUTE VALUE of THE DISCRIMINANT of ABELIAN FIELDS of DEGREE p(2)

Interlando, J. Carmelo; Dantas Lopes, Jose Othon; Da Nobrega Neto, Trajano Pires; Flores, Andre Luiz
Fonte: World Scientific Publ Co Pte Ltd Publicador: World Scientific Publ Co Pte Ltd
Tipo: Artigo de Revista Científica Formato: 819-824
Português
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46.839062%
Let p be a prime number. A formula for the minimum absolute value of the discriminant of all Abelian extensions of Q of degree p(2) is given in terms of p.

## ‣ Motor Preparatory Activity in Posterior Parietal Cortex is Modulated by Subjective Absolute Value

Iyer, Asha; Lindner, Axel; Kagan, Igor; Andersen, Richard A.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.839062%
Cortical motor planning is shaped by “subjective absolute value”: planning activity is strongly enhanced for large expected gains in subjects who believe they perform well; conversely, activity is higher for large expected losses in subjects who think they perform poorly.

## ‣ Reducing the Standard Deviation in Multiple-Assay Experiments Where the Variation Matters but the Absolute Value Does Not

Echenique-Robba, Pablo; Nelo-Bazán, María Alejandra; Carrodeguas, José A.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.94545%
When the value of a quantity for a number of systems (cells, molecules, people, chunks of metal, DNA vectors, so on) is measured and the aim is to replicate the whole set again for different trials or assays, despite the efforts for a near-equal design, scientists might often obtain quite different measurements. As a consequence, some systems’ averages present standard deviations that are too large to render statistically significant results. This work presents a novel correction method of a very low mathematical and numerical complexity that can reduce the standard deviation of such results and increase their statistical significance. Two conditions are to be met: the inter-system variations of matter while its absolute value does not, and a similar tendency in the values of must be present in the different assays (or in other words, the results corresponding to different assays must present a high linear correlation). We demonstrate the improvements this method offers with a cell biology experiment, but it can definitely be applied to any problem that conforms to the described structure and requirements and in any quantitative scientific field that deals with data subject to uncertainty.

## ‣ X-Ray Reflectivity from the Surface of a Liquid Crystal: Surface Structure and Absolute Value of Critical Fluctuations

Pershan, Peter S.; Als-Nielsen, J.
Fonte: American Physical Society Publicador: American Physical Society
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.839062%
X-ray reflectivity from the surface of a nematic liquid crystal is interpreted as the coherent superposition of Fresnel reflection from the surface and Bragg reflection from smectic order induced by the surface. Angular dependence of the Fresnel effect yields information on surface structure. Measurement of the intensity of diffuse critical scattering relative to the Fresnel reflection yields the absolute value of the critical part of the density-density correlation function.; Engineering and Applied Sciences

## ‣ Logarithmic and absolute-value like properties of $\pi(x)$ with applications

Benyaminov, Boris B.
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.839062%
We derive properties of $\pi(x)$ reminiscent of those of the logarithm and absolute value functions. Two of these properties are similar to the relations defining the linearity of a function. Several applications of these properties of $\pi(x)$ are also examined.; Comment: 11 pages. Withdrawn by the author due to a problem with Theorem 3.1, thus also invalidating all results that were based on it

## ‣ Measurements of the absolute value of the penetration depth in high-$T_c$ superconductors using a tunnel diode resonator

Prozorov, R.; Giannetta, R. W.; Carrington, A.; Fournier, P.; Greene, R. L.; Hinks, D. G.; Banks, A. R.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.839062%

## ‣ Empirical Formula of the Absolute Value of Electrical Conductivity for Elemental Metals and Its Interpretation By Fluctuation Dissipation Theorem

Tipo: Artigo de Revista Científica
Relevância na Pesquisa
46.839062%
The absolute value of the electrical conductivity sigma of elemental metals even at the room temperature range is not well theoretically understood. This is particularly true in multivalent metals. This paper empirically found that sigma=n_{atom}e^2tau0/mG with tau0=hbar/k_{B}T reproduces the observations rather well for many metals as in Fig.1(b)-upper, if G is taken, by guessing to be a summed number of electric bands counted from outer most orbitals. We find by comparative study at the same time n_{atom}=n, namely Z=1 and m=m^* for majority of metals for sigma. Thus the only quantity remained is tau. The Bardeen's tau is found equal to tau0 if the deformation potential is equal to Fermi energy, using the observationally ascertained fact that thermal acoustic energy=the Fermi energy. Since electrons behave nearly as free electrons, the wave function should show the minimum uncertainty relation of Delta p_{x} Delta_{x}=hbar/2, which following the classical Fluctuation-Dissipation-Theorem shows in fact tau0=hbar/k_{B}T.; Comment: 12 pages, 2 figures

## ‣ On the absolute value of the air-fluorescence yield

Rosado, J.; Blanco, F.; Arqueros, F.
Tipo: Artigo de Revista Científica
Relevância na Pesquisa
47.197993%
The absolute value of the air-fluorescence yield is a key parameter for the energy reconstruction of extensive air showers registered by fluorescence telescopes. In previous publications, we reported a detailed Monte Carlo simulation of the air-fluorescence generation that allowed the theoretical evaluation of this parameter. This simulation has been upgraded in the present work. As a result, we determined an updated absolute value of the fluorescence yield of 7.9+-2.0 ph/MeV for the band at 337 nm in dry air at 800 hPa and 293 K, in agreement with experimental values. We have also performed a critical analysis of available absolute measurements of the fluorescence yield with the assistance of our simulation. Corrections have been applied to some measurements to account for a bias in the evaluation of the energy deposition. Possible effects of other experimental aspects have also been discussed. From this analysis, we determined an average fluorescence yield of 7.04+-0.24 ph/MeV at the above conditions.; Comment: Submitted to Astroparticle Physics

## ‣ Motor Preparatory Activity in Posterior Parietal Cortex is Modulated by Subjective Absolute Value

Iyer, Asha; Lindner, Axel; Kagan, Igor; Andersen, Richard A.
Fonte: Public Library of Science Publicador: Public Library of Science
Tipo: Article; PeerReviewed Formato: application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf; application/pdf