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Screened modified gravity predicts potentially large signatures in the peculiar velocity field that makes it an interesting probe to test gravity on cosmological scales. We investigate the signatures induced by the Symmetron and a Chameleon f(R) model in the peculiar velocity field using N-body simulations. By studying fifth force and halo velocity profiles, we identify three general categories of effects found in screened modified gravity models: a fully screened regime where we recover Λ cold dark matter to high precision, an unscreened regime where the fifth force is in full operation, and, a partially screened regime where screening occurs in the inner part of a halo, but the fifth force is active at larger radii. These three regimes can be pointed out very clearly by analysing the deviation in the maximum cluster velocity. Observationally, the partially screened regime is of particular interest since an uniform increase of the gravitational force - as present in the unscreened regime - is degenerate with the (dynamical) halo mass estimate, and, thus, hard to detect. [ABSTRACT FROM AUTHOR]

We present a novel solver for an analogue to Poisson's equation in the framework of modified Newtonian dynamics (MOND). This equation is highly non-linear and hence standard codes based upon tree structures and/or FFT's in general are not applicable; one needs to defer to multi-grid relaxation techniques. We present results from the first cosmological simulations we made to compare cosmological structure formation of in the two paradigms. We found compatible results between the two simulations, at least at redshift z = 0. [ABSTRACT FROM AUTHOR]

Extending general relativity by adding extra degrees of freedom is a popular approach for explaining the accelerated expansion of the Universe and to build high energy completions of the theory of gravity. The presence of such new degrees of freedom is, however, tightly constrained from several observations and experiments that aim to test general relativity in a wide range of scales. The viability of a given modified theory of gravity, therefore, strongly depends on the existence of a screening mechanism that suppresses the extra degrees of freedom. We perform simulations, and find that waves propagating in the new degrees of freedom can significantly impact the efficiency of some screening mechanisms, thereby threatening the viability of these modified gravity theories. Specifically, we show that the waves produced in the symmetron model can increase the amplitude of the fifth force and the parametrized post Newtonian parameters by several orders of magnitude. [ABSTRACT FROM AUTHOR]

The article describes the case of a 43-year-old woman who underwent cystic uterine leiomyoma degeneration imaging using GE Medical Systems' HDlive imaging system. Topics discussed include the patient's history of intramural uterine myoma with menorrhagia and severe anemia, her presentation to the gynecological clinic with lower abdominal pain and distension after treatment with ulipristal acetate, and the identification of a large cystic mass following ultrasound examination.

• Analysis of acoustic performance parameter through psychoacoustic study. • Correlation between subjective assessment and objective rating of insertion loss. • Saturation of Perveived Annoyance Reduction above high values of attenuation. • Significant differences in the Perceived Annoyance Reduction by gender and nationality. There are several international standards that define the way to evaluate the attenuation capacity of noise reducing devices, by single-number quantities representing airborne sound insulation and insertion loss. These two single-value ratings define the quality and performance of acoustic barriers, the former being related to intrinsic and the latter to both intrinsic and extrinsic acoustic characteristics of the devices. However, not many studies can be found on whether these objective parameters correlate to the perception of annoyance reduction. The aim of the present work is to analyze the adequacy of these objective ratings to indicate the performance of noise barriers, by comparing their values with the perception of annoyance reduction. For this purpose, ninety individuals of two different nationalities (Spanish and Portuguese) were asked to rate the perceived annoyance reduction in a listening experimental test, in which they were exposed, under controlled conditions, to several environmental noises and acoustic screened stimuli simulated by audio filters. The obtained results show a high correlation between objective ratings and subjective annoyance perception, with a better correlation being observed for insertion loss single-number parameter than for the airborne sound insulation single-number rating. Furthermore, significant differences were found depending on the gender and nationality of the respondents. The results, from this ongoing research work, may be of great interest for future acoustic barriers design. [ABSTRACT FROM AUTHOR]

Presents a study which derived the ionization coefficients of holes and electrons in Ga[sub0.96]Al[sub0.04]Sb from the variations of the photocurrent multiplication as a function of the reverse bias in Be-implanted p[sup+] Ga[sub0.96]Al[sub0.04]Sb/n Ga[sub0.96]Al[sub0.04]Sb/n[sup-1] GaSb mesa diodes. Method; Experimental details; Conclusion.

CuIn3Se5 polycrystalline thin films have been prepared by flash evaporation. Their properties have been investigated by X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy, photoconductivity, optical transmission, Hall effect and four-point probe resistivity measurement. The results showed that the phase of the ordered defect compound CuIn3Se5 has unit cell parameters a and c with values 5.7508 and 11.5769 A˚, respectively. It has an optical band gap of 1.23 eV and an optical absorption of about 0.9×104 cm−1 for photon energy hν>3.8 eV. The concentration of majority carriers at room temperature is n=1.16×1015 cm−3, the mobility is 4.3 cm2/V s and the films resistivity is ρn=1.25×1013 Ω cm. [Copyright &y& Elsevier]