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A cycle of works on manufacturing and studying laser and magnetooptical ceramics with a focus on their thermo-optical characteristics performed by the research team is analyzed. Original results that have not been published before such as measurements of the Verdet constant in the Zr:TAG, Re:MgAl 2 O 4 , and ZnAl 2 O 4 ceramics are also presented.

Prospects for using ZnSe polycrystals synthesized by the chemical vapor deposition (CVD) method for the development of Faraday isolators for high-power radiation at a wavelength of 1076 nm are investigated. A Faraday isolator was built by a conventional scheme for room temperature operation. No thermally induced depolarization was observed in the device for the laser power range up to 1270 W, which is the main limiting factor for powerful isolators. It was demonstrated experimentally that thermally induced depolarization is not expected at powers up to 2.5 kW.

Presented herein are the results of treatment of 137 patients with infrarenal aneurysms of the abdominal portion of the aorta in a combination with ischaemic heart disease. Severity of lesions to the coronary bed and the risk of cardiac complications were assessed according to the SYNTAX score. Depending on severity of angina pectoris and the clinical course of infrarenal aortic aneurysms, we used different tactical approaches to operative treatment of patients. In a low risk of coronary complications, we performed isolated prosthetic repair or endoprosthetic reconstruction of the abdominal aorta. In patients with haemodynamically significant lesions of the coronary bed and positive non-invasive tests, the first stage consisted in coronary artery bypass grafting or stenting of coronary arteries taking into account the risk of cardiac complications according to the SYNTAX Score. The second stage consisted in prosthetic repair or endoprosthetic reconstruction of the abdominal aorta. The terms of the second stage differed and were determined by the course of abdominal aortic aneurysms. In symptomatic large aneurysms (more than 8 cm), prosthetic repair of the abdominal aorta was carried out within 2 weeks after previous stenting of coronary arteries. Simultaneous myocardial revascularization and abdominal aortic reconstruction were performed only in patients with severe angina pectoris, lesions of the trunk of the left coronary artery, three-vessel lesions of the coronary bed, high risk of cardiac complications according to the SYNTAX Score and a complicated or symptomatic course of an infrarenal aortic aneurysm. During implantation of stent grafts into the abdominal aorta there were neither lethal outcomes nor cardiac complications. In open operations, the 30-day mortality rate amounted to 2.2%, with the 5-year survival rate of 92%.

Thermo-optical characteristics of a new magneto-active material, Na(0.37)Tb(0.63)F(2.26) crystal, were investigated in this Letter. This crystal has a high value of magneto-optical figure-of-merit and negative optical anisotropy parameter that makes it a promising material for development of Faraday isolators for high-power lasers; in particular it gives opportunities for the realization of new schemes of optical isolators.

A Faraday isolator based on a new magneto-optical medium, TSAG (terbium scandium aluminum garnet) crystal, has been constructed and investigated experimentally. The device provides an isolation ratio of more than 30 dB at 500 W laser power. It is shown that this medium can be used in Faraday isolators for kilowatt-level laser powers.

We propose a new type of Faraday isolator with compensation of the azimuthally symmetric component of polarization distortions by means of magnetic field inhomogeneity. The depolarization was attenuated in experiments by a factor of 7.

The influence of paramagnetic magnetization of magneto-optical elements on the characteristics of Faraday isolators is studied. The theoretical estimates confirmed by the experiment indicate that this effect should be taken into consideration, particularly when designing large-aperture and cryogenic Faraday isolators.

To elucidate the biochemical roles of singlet molecular oxygen (1(O2)) in the light-dependent reactions photosensitized by biological blue-light photoreceptors, time-resolved measurements of photosensitized 1O2 phosphorescence (1270 nm) were performed in air-saturated aqueous ((D2)O) solutions of pterins (2-amino-4-hydroxy-6,7-dimethylpteridine (DMP) and 2-amino-4-hydroxy-6-tetrahydroxybutyl-(D-arabo)pteridine (TOP)) and flavins (riboflavin and flavin mononucleotide (FMN)) under excitation with nitrogen laser (337.1 nm) pulses. The 1(O2) quantum yields were found to be 0.16, 0.20, 0.50, and 0.50 for DMP, TOP, riboflavin, and FMN, respectively. The data indicate that pterins and flavins are rather efficient photosensitizers of 1(O2) production that might be important for their photobiological functions.