Nonreciprocal Linear Transmission of Sound in a Viscous Environment with Broken P Symmetry.

Reciprocity is a fundamental property of the wave equation in a linear medium that originates from time-reversal symmetry, or T symmetry. For electromagnetic waves, reciprocity can be violated by an external magnetic field. It is much harder to realize nonreciprocity for acoustic waves.

Intermittent flow regimes near the convection threshold in ferromagnetic nanofluids.

The onset and decay of convection in a spherical cavity filled with ferromagnetic nanofluid and heated from below are investigated experimentally. It is found that, unlike in a single-component Newtonian fluid where stationary convection sets in as a result of supercritical bifurcation and where convection intensity increases continuously with the degree of supercriticality, convection in a multicomponent ferromagnetic nanofluid starts abruptly and has an oscillatory nature. The hysteresis is observed in the transition between conduction and convection states.

Thermomagnetic convective flows in a vertical layer of ferrocolloid: perturbation energy analysis and experimental study.

Flow patterns arising in a vertical differentially heated layer of nonconducting ferromagnetic fluid placed in an external uniform transverse magnetic field are studied experimentally and discussed from the point of view of the perturbation energy balance. A quantitative criterion for detecting the parametric point where the dominant role in generating a flow instability is transferred between the thermogravitational and thermomagnetic mechanisms is suggested, based on the disturbance energy balance analysis. A comprehensive experimental study of various flow patterns is undertaken, and the existence is demonstrated of oblique thermomagnetic waves theoretically predicted by Suslov [Phys.

[Dynamics of postinfarction left ventricular remodeling during long term use of perindopril, amiodarone, and beta-adrenoblockers].

Perindopril was used in 287 patients with left ventricular ejection fraction < or =40% for 1 year after myocardial infarction either alone (n=53), or in combination with amiodarone (n=53), metoprolol (n=32), bisoprolol (n=32), carvedilol (n=32), atenolol (n=32), amiodarone and carvedilol (n=53). According to echocardiography data the use of combination of perindopril with metoprolol and especially carvedilol but not with amiodarone, bisoprolol, or atenolol, was associated with augmented anti-remodeling effect. The use of metoprolol, bisoprolol, and carvedilol but not of atenolol was associated with improvement of left ventricular systolic function.

[Late effects of long-term exposure to low-dose ionizing radiation on lymphoid pharyngeal system in children].

The examination of 468 children and adolescents estimated frequency and structure of chronic pathology of the pharyngeal ring in long-term exposure to low-dose radiation. Chronic disease of the tonsils and adenoids was detected in 194 children (45.4%).