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The mismatch repair (MMR) system detects non-Watson - Crick base pairs as well as the defects, appearing in course of DNA replication, and helps to eliminate them by catalyzing the excision of the defect-containing region of daughter DNA and its error-free resynthesis. Thus, MMR remarkably improves the fidelity of replication. After separation, both strands contain non-repairable damages and the mismatches may generate DnA mutation in 50 % of cell progeny after next replication. MMR dysfunction causes surge of mutation rate, abnormal recombination, and cancer in humans and animals. Therefore, the main MMR efficiency parameter is mismatch correction before the next replication cycle. Mismatch detection is made by the MSH2 protein, which forms a heterodimer with either MSH6 or MSH3 (Mut S), depending on the damage (MSH6 is needed for the amendment of single base mispairs, whereas both MSH3 and MSH6 can correct IDLs). A heterodimer of MLH1 and PMS2 (Mut L) controls the interaction between the mismatch-detecting complex of proteins and other proteins essential for MMR, including exonuclease 1, helicase, nuclear antigen of proliferating cells, single-stranded DNA-binding protein and DNA polymerases δ and ε. MLH1 can form a heterodimer with two additional proteins - MLH3 and PMS1. PMS2 is required for the correction of single based mismatches, and PMS2 and MLH3 contribute to the correction of IDLs. The Nobel Prize in Chemistry 2015 was awarded for the studies of DNA repair, i.a. MMR.

Partial arthroplasty of the lower jaw at the present stage is one of the alternative methods of rehabilitation of patients with tumors or traumatic injury maxillofacial area. Project resection implant automatically using special CAD / CAM software. The aim of our study was to design the resection implant (endoprosthesis) of chin areas of the mandible. The challenge was to design a computer endoprosthesis that most accurately reproduce the shape and size of bones, shattered pathological process and allowed to carry out effective dental prosthetics based on dental implants. For information on the exact geometry of the lower jaw and place of destruction carried out scanning the patient's face and Cone-beam CT scanner on the unit PAX-Zenit 3D slice thickness of 0.1 mm, followed by an analysis of the data in the program Mimics. For the design of the implant resection of chin areas of mandible an analysis of CT scans of the patient B., 26 years old was used. The front of the lower jaw, including the area chin torus, began to collapse as a result of a benign tumor. An analysis of the received set of image format DICOM was performed. For processing images and create 3D-models continue to use the system of processing medical data Materialise Mimics (Belgium, 1992-2014). After creating a project import it image CT. On the basis of built 3D-model. It was created solid models applications Cad-system Delcam Powershape. It was determined the limits of resection, they pass no closer than 2 mm to the affected tissue. It was build internal and external surfaces of the prosthesis. Then the lateral and upper and lower surfaces. It was created fasteners prosthesis to the jaw and a smooth transition from their bases to the outer surface of the prosthesis. The next step is adding surface that correspond to the installation site abutments. In this case, the size used for two-stage implant Vitaplant V2Km 400 (d = 4 mm, l = 10 mm). Build appropriate surface carving part, hexagon and conical surfaces. Based on the model established pattern, the edge of which resect jaw. Template during surgery is applied to the front part of the bone and fastened in places where the prosthesis in order to accurately passed resection. All models are tested after creating the required " doctor body" to ensure that no defects such as holes are invisible, overlay surfaces, defective points, gaps and others.

Получено граничное интегральное представление для линейных векторных полей Бельтрами, позволяющее вичислить значение вектора в любой точке области с помощью его касательных компонент на границе. Приведены два интегральных представления, отлича­ющихся порядком производных касательных компонент на границе. Показана связь полу­ченного решения с решениями уравнения Гельмгольца.

Для произвольных векторных полей, удовлетворяющих условию соленоидальности, по­лучено граничное интегральное представление в виде ряда, каждый член которого пред­ставляет собой поверхностный интеграл по границе области, содержащий значения поля и его роторов различного порядка. Выведены новые граничные интегральные уравнения для ряда линейных уравнений в частных производных.

This paper studies the anode region of an eroding anode with a nonstationary arc-root attachment. High-current free-burning short as well as long arcs at atmospheric pressure are investigated. A technique to study the anode region of the arc is suggested. An anode moving perpendicular to the arc axis was used for estimating parameters of the anode jets at a given moment of their development. The mechanism of current transfer in the anode region is considered on the basis of electrophysical and optical-spectroscopic investigations of the arc attachment traces and plasma parameters both of the anode jet and arc column. The anode jet was found to be of importance in the stationary arc operation. The near-anode plasma parameters depend on the effect of the cathode jet. In short arcs ([L.sub.a] [similar to] 2 mm, the plasma temperature at the anode exceeds 20000 K, while in long ares ([L.sub.a] > 50 mm), it falls below 7000 K. At plasma temperature [T.sub.a] > 11 000 K, the total arc current in the anode region is transferred through the arc plasma, while at lower temperatures, both the arc column and the anode jet take part in the current transfer. Index Terms - Anode region, anode spot, current transfer, high-speed imaging, temperature, vapor jet.