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High-grade gliomas have a diffuse and infiltrative nature of the growth of tumor cells, due to which the achievement of radical resection is difficult. Surgical resection completeness of brain tumors is an important factor in prolonging the life of patients. An accurate definition of tumor boundaries and residual fluorescent regions is impossible due to imperfections of the equipment used for fluorescent imaging. 5-aminolevulinic acid (5-ALA) is a precursor of protoporphyrin IX (PpIX) in humans and is clinically used to detect and treat tumors. Currently, fluorescence-guided surgery with PpIX used a surgical microscope with an excitation wavelength in the blue spectrum range. Because of its low ability to penetrate into biological tissue, blue light is ineffective for providing high-quality fluorescent navigation. Also, when performing an operation using radiation in the blue spectrum range, the photosensitizer’s surface layer (PS) often bleaches out, which leads to frequent errors. The use of red light emission makes it possible to slow down the PS bleaches out due to the absorption properties of PpIX, but this task is technically more complicated and requires highly sensitive cameras and specialized optical filters. The new two-channel video system for fluorescent navigation has a radiation source in the red range of the spectrum, the penetration depth of which is greater than the blue light, which makes it possible to increase the depth of probing into biological tissues. The study’s clinical part involved 5 patients with high grade glioma and 1 patient with low grade glioma: grade III oligodendrogliomas (2), grade IV glioblastomas (3), and grade II diffusion astrocytoma (1).

In neurosurgery exists a need to treat deep-seated brain tumors by stereotactic photodynamic therapy. Since access to tumor is limited and carried out through a small diameter hole, the choice a suitable equipment is difficult. To improve the treatment method, we have developed a single-fiber system for delivery laser radiation and determining the photosensitizer concentration in a biological object.

The reliability of the glass used in spacecraft windows depends on the size of the defects forming upon the impingement of meteoritic particles on a window, as well as the size, density, velocity, and angles of impingement of the particles. In this article, based on the theory of the strength in a double-layer model, formulas are developed that express the dependence of the residual glass strength on the diameter, density, velocity relative to the first cosmic velocity, and angles of impingement of the particles.

The spectral features of the energy structure of Co2+, Ni2+, and Fe2+ ions in semiconductor materials ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe and the relation of these structures to the band gap are studied. The feasibility of lasing in these materials in the range of 1.5–3 µm is estimated.