Alignment-to-orientation conversion and nuclear quadrupole resonance

The role of alignment-to-orientation conversion (AOC) in nuclear quadrupole resonance (NQR) is discussed. AOC is shown to be the mechanism responsible for the appearance of macroscopic orientation in a sample originally lacking any global polarization. Parallels are drawn between NQR and AOC in atomic physics.Comment: 4 pages, 3 figures, v2: reorganized, Appendix adde

Laser Conoscopy Study of Optical Anomalies in Uniaxial Crystals

New experimental possibilities of detecting fine optical anomalies in uniaxial crystals are demonstrated on a level with numerical estimation of refractive index and mechanical stress variations that cause distortions of the optical indicatrix. New possibilities are due to the use of an exact equation for isochromes derived for uniaxial crystals without mathematical simplifications commonly used by other authors. It allows one to calculate and graphically reproduce the theoretical form of isochromes of any orders in the conoscopic picture of an ideal crystal with known principal refractive indices, the thickness and orientation of the crystal surfaces, and also the wavelength of the radiation and the parameters of the optical circuit. A computer comparison of the theoretical image with an experimental conoscopic picture of a real crystal, fixed by a color digital camera on a semitransparent screen, is performed. The data on the variations of refractive indices and mechanical stresses in the crystal are retrieved from the mathematical processing of differences in the conoscopic images. The applications of the proposed method for the analysis of optical homogeneity of paratellurite and lithium niobate single crystals are presented. Keywords: method of conoscopy, isochromes, piezo-optic effec

Conoscopic study of strontium-barium niobate single crystals

Optically transparent single crystals of strontium-barium niobate, Sr xBa1-xNb2O6, of different compositions (x 0.26...0.7) were examined with the aid of conoscopic light interference figures. A regular change of the isochrome concentric ring number and diameters consistent with the temperature variation of the value of birefringence is demonstrated by direct observations of polar cuts of optically uniaxial samples. Anomalous violations of the conventional (uniaxial) interference patterns occur occasionaly in some samples being indicative of the existence of biaxial trait in their behaviour even though no voltage is applied. These features may depend on annealing treatments at elevated temperatures. The results of the study show that conoscopic images may serve as a sensitive indicator of the structural state of SBN crystals related to the effects of stress-induced change of optical anisotropy and temperature dependent birefringence parameters

МОДЕЛИРОВАНИЕ ГРАФИКА НА ОДНОПУТНОЙ ЛИНИИ

he author proposes an approach towards a mathematical model that permits to prepare the schedule of train traffic at a single-track railway. Therefore, he describes the initial arguments and solution sequence in order to achieve the necessary rates. The author designates conditions and restrictions, which admit a certain choice of variants taking into consideration the existing prioritiesПредложен подход к построению  математической модели,  позволяющей осуществлять  разработку графика движения  поездов на однопутной линии.  Изложены исходные позиции  и последовательность решения  задачи для получения заданных  показателей. Названы условия  и ограничения, допускающие выбор  вариантов с учетом имеющихся  приоритетов

Dispersion of Switching Processes in Ferroelectric Ceramics

The influence of the switching processes on self-heating of ferroelectric PZT ceramics samples was studied in high-amplitude sine and meander electric fields in a wide frequency range of 50 to 1500 Hz. It is shown that the linear dependence of the self-heating temperature on the electric field frequency is observed only in low-frequency region. It was found that there exists a maximum on the frequency dependence of the self-heating temperature. The critical frequency fcr corresponding to this maximum depends on both the properties of the material and geometry of the sample

SUCCESSFUL ENDOVASCULAR TREATMENT FOR LCA TRUNK TRIFURCATION LESION

Left coronary artery (LCA) supplies blood to 75–100% of myocardial volume of the left ventricle (LV). The atherosclerotic lesion of LCA trunk causes an ischemia in the sufficient area of the myocardium that often results in LV dysfunction, heart failure, and arrhythmia. The risk of death in cases with this pathology reaches 50% at drug treatment. Several decades, coronary artery bypass graft surgery (CABG) was considered as "the golden standard" of treatment for LCA trunk stenosis. Due to the skills and experience in treatment for coronary pathology, new technologies development and stenting techniques, percutaneous transluminal coronary angioplasty (PTCA) for LCA trunk stenosis became more effective and safe treatment. Despite this, trifurcation of LCA trunk remains extremely difficult pathology for endovascular treatment, for a lack of sufficient experience. In the present paper we described successful endovascular treatment for trifurcation lesion of LCA trunk in a case with acute coronary syndrome (ACS)

Possible treatment approaches for distal coronary artery perforation

Coronary artery perforation is a rare (0.1–3.0%) but rather severe complication that occurs during the coronary interventions. Treating the perforation caused by the coronary conductor is extremely complicated, as it could be caused quite unexpectedly and may be accompanied by catastrophic consequences if misdirected. Choosing effective treatment techniques is not easy, as evidenced by hospital and remote clinical outcomes with high mortality rates

Research in the history of the profession as an essential part oh the formation of a specialist

In this research we have shown the necessity of studying history of Pharmacy as a factor of completely developed specialist in Pharmacy on the example of the history of forming specialist “pharmacist” using general scientific theoretical method (analysis). In this study we have monitored the influence of historical knowledge of this aspect on the modern scientific medical society.В настоящем исследовании при помощи теоретического общенаучного метода (анализа), выявляется необходимость изучения истории профессии как фактора полноценного формирования специалиста на примере специальности «фармацевт». В ходе работы на данном уровне исследования удалось проследить процесс влияния исторических знаний в данном аспекте на формирование будущего специалиста

Martensite and magnetic domain structure in ferromagnetic shape memory single-and polycrystals

Abstract Magnetic shape memory effect observed in a number of materials is based on the coexistence and cooperation of closely correlated ensembles of martensite and magnetic domains. In the present work we describe the results of an experimental study of the domain structure (DS) of poly-and single crystals of ferromagnetic Co-Ni-Ga and Ni-Mn-Ga Heusler alloys making use of a number of optical techniques including magnetooptical imaging films (MOIF), interference and digital differential microscopy