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A method has been developed for constructing three-dimensional models of rigid objects on the earth’s surface using one satellite image using the example of railway infrastructure. The method consists in step-by-step processing of satellite images with sequential application of two convolutional neural networks. In the first processing step, a satellite image is segmented by a neural network to select a plurality of objects of predetermined classes. At the second stage of processing with the help of neural network local analysis of image areas detected by results of the first stage of processing is performed. The results of the second processing step are used to estimate the parameters of the 3D model of the object. The possibilities of the method are shown by the example of processing a satellite image of the railway infrastructure. The following classes of informative areas are considered: building, wall edge, roof edge, building shadow, railway infrastructure, car, highway; rails, poles and shadows from poles (taken as reference objects for estimating scaling coefficients in certain directions). An example is given of using the developed method of highlighting typical railway infrastructure objects and for subsequent evaluation of the parameters of a three-dimensional building model partially obscured by trees.

A way of constructing 3D models of rigid objects from one satellite image is described. It is based on the use of two convolution neural networks which sequentially process high-resolution satellite images. The first neural network performs integral image analysis for segmentation and identification of objects of specified physical classes. The second neural network performs local image analysis and works with images segmented by the first neural network in areas of the image that presumably contain objects of specified classes. An algorithm for reconstructing a 3D model of an object from raster domains of a segmented image obtained from local analysis is described. It is based on regression analysis, the assessing of equivalent figures, and the linearization and polarization of contours. Results from the algorithm’s operation are given using the example of railway infrastructure facilities. The results from constructing 3D models of three objects of the railway infrastructure, identified via the operation of neural networks for four informative classes of areas are presented, e.g. roofs, walls, railroad tracks, contanc lines (poles). Standard dimensions (e.g., the railway gauge (1.52 m) and the height of railway support poles (11.35 m)) are used to estimate scaling coefficients that allow determination of base dimensions and object heights. The possibility of constructing 3D models of objects of areas from 210 to 4200 m2 is shown.

Due to many negative and undesirable side effects from the use of permanent implants, the development of temporary implants based on biocompatible and biodegradable materials is a promising area of modern medicine. In the presented study, we have investigated complex-shaped iron-silicon (Fe–Si) scaffolds that can be used as potential biodegradable framework structures for solid implants for bone grafting. Since iron and silicon are biocompatible materials, and their alloy should also have biocompatibility. It has been demonstrated that cells, mesenchymal stromal cells derived from the human umbilical cord (UC-MSC) and 3T3, were attached to, spread, and proliferated on the Fe–Si scaffolds’ surface. Most of UC-MSC and 3T3 remained viable, only single dead cells were observed. According to the results of biological testing, the scaffolds have shown that deposition of calcium phosphate particles occurs on day one in the scaffold at the defect site that can be used as a primary marker of osteodifferentiation. These results demonstrate that the 3D-printed porous iron-silicon (Fe–Si) alloy scaffolds are promising structures for bone grafting and regeneration.

The use of stem cell technologies in retinal defect reparation therapy has produced beneficial results. Nowadays, numerous protocols exist which provide a neural differentiation of the stem cells transplanted into the retina. However, questions concerning the functional replacement of the missing retinal neurons by transplanted cells thus far remain unanswered. The organotypic culture protocol was used in this study in order to prove the possibility of transdifferentiation of bone marrow stromal cells (MMSCs) and neural stem/progenitor cells (NSPCs) from EGFP-positive mice and the functional integration of these cells. This technique enables a detailed characterization of cell behavior post-transplantation. Using atomic force microscopy, we reliably demonstrated the difference (p < 0.01) between the thickness of the outgrowths formed by glial and endothelial retina cells and the thickness of neurites and neuro-like transplanted MMSC outgrowths. MMSCs are also shown to form synapses up to 2.5 ± 0.06 µm in diameter on day 4 after the transplantation. Following electrical stimulation (20V, 0.5Hz, 200ms), clear depolarization of retinal neurons and their outgrowths is detected. It is shown that some of these GFP+ MMSCs, which changed their morphology after the transplantation in retinal explants to neuro-like MMSCs, are capable of depolarizing after exogenous stimulation.

During the study of diode laser radiation effect in micropulse mode on culture cells of human retinal pigment epithelium it was revealed that the quota of dead cells was a minimum. Besides, a certain conformity between dead cells quota and parameter characteristics of laser radiation. Based on the performed experimental study it was revealed that for a work using the Iris Medical IQ 810 diode laser in the micropulse mode following parameters: duration of pulse set--300ms, duration of function--9.1%, power--750mW are safe for retinal pigment epithelium cells. Rationales of safety in application of the infrared diode laser radiation in micropulse mode in clinic for treatment of age-related macular degeneration (AMD) exampled by cell culture of human retinal pigment epithelium.

The effect of antisense oligonucleotides specific to mRNA of the proapoptotic gene harakiri (Hrk) on the development of mouse SAMP1 (senescence-accelerated mouse prone) and (C57BL/6J x DBA/2J)F1 preimplantation embryos cultured in vitro was investigated. The SAMP1 mice are characterized by genetically determined decrease of fertility along with the highly frequent perturbations of embryonic development. Reproduction indices of the (C57BL/6J x DBA/2J) hybrids lie within the normal range. Because of this, preimplantation abnormalities in this line were induced by the action of proapoptotic agent bleomycine. It was demonstrated that antisense inhibition of the Hrk expression had no effect on the frequency of genetically determined abnormalities of early embryonic development in SAMP1 mice. In case of induced abnormalities, addition of oligonucleotides specific to mRNA of proapoptotic Hrk gene influenced the number of abnormalities, and at the same time, improved the quality of survived embryos via increasing the blastocyst hatching.

A hundred fifty four invasive diagnostic and therapeutical interventions were made in patients with diseases of the abdomen and retroperitoneal space under ultrasonographic guidance. Various biopsies were performed in 139 patients; positive results were achieved in 120 (86.3%) cases. In 15 patients, diagnostic biopsies were combined with therapeutical interventions, such as aspiration of cysts in the liver (n = 3) and kidney (n = 2); drainage of abscesses in the abdomen (n = 5) and liver (n = 5). Fourteen patients with mechanical jaundice caused by extrahepatic bile duct tumors or pancreatic head cancer underwent percutaneous transhepatic cholecystocholangiography followed by external drainage. Percutaneous transhepatic drainage of the gallbladder was made in 1 patient with acute cholecystitis.

MRI findings of 13 patients with soft tissue tumors (STT) are presented. There are were abnormalities, such as primary STTs of the hip in 5 patients, the back in 1, and the neck in 1, STT relapses of the hip in 2 and those of the back in 1. Two patients had chronic hip STT hematomas and 1 had hip STT metastatic melanoma. The diagnosis was verified in 11 cases (in 10 cases at surgery and 1 at needle biopsy). MRI makes it possible to define the accurate sizes of the tumor, its structure and relationship to its adjacent tissues, which is important in choosing at treatment policy, the type and scope of a surgical interventions.

Exploratory and therapeutical punctures were made in 454 patients under the control of ultrasound, CT, and X-ray teleimage. Diagnostic biopsies established the cytological and histological nature of diseases in 67.6% of cases, positive ultrasound-, CT-, and X-ray teleimage-controlled biopsies being 76.3, 64.9, and 71.4%, respectively. Beneficial effects of therapeutical interventions were obtained in 89.5% of patients.

The authors analyse the results of computer-aided tomographic biopsies in 81 patients with various pulmonary diseases (63 with tumors, 53 of these with malignant ones, and 18 with nontumors diseases). Positive results were obtained in 86.4% of cases. Biopsies proved to be informative in 44 out of 48 patients with lung cancer, in 8 out of 10 ones with benign tumors, and in 10 out of 12 ones with nonspecific inflammations. The results were not informative in 13.6% of patients. In 4 cases the failure was caused by the absence of cellular material in the puncture biopsy specimen, in 5 it was due to the presence of only pulmonary cells. In two more cases the diagnosis of lung cancer made by computer-aided biopsy was erroneous because of the presence of inflammation elements and amorphous mass in the examined. Complications occurred in 22 (27.2%) patients, pneumothorax in 16 (19.8%) and local pulmonary hemorrhages in 6 (7.4%) of these. Hence, computer-aided biopsy of the lung is an informative diagnostic method, permitting a correct diagnosis in the majority of cases.

CT myelotomography was carried out in 262 patients with various conditions of the spine and cord. Pathologic changes were detected in 233 (87.6%) of the examinees. The most frequent diseases were tumors and metastases (59 cases), degenerative processes, including primary and recurrent hernias (59 cases), atrophic processes (46 cases). The accuracy of the diagnosis was found to be 98.6%. A false-positive result was obtained in one case with a suspected tumor of the cord. No complications were recorded. Computer-aided myelotomography is an effective method for the diagnosis of involvement of the spine and cord.

The article analyses the results of 104 biopsies which were carried out in 84 patients with different diseases of the organs of thoracic (50) or abdominal (16) cavities, postperitoneal space (32), bones and soft tissues (6). Positive results were obtained in 67 cases, negative--in 26, false-negative--in 11. The specificity was 70.3%, sensitivity--100%, authenticity--64.4%. The authors make a conclusion that the results and authenticity of biopsies depend on such factors as the proper organ to be punctured, character and structure of the affection, its location, volume and spreading, as well as the type of needles to be used.

Invasive interventions (diagnostic and therapeutic) were conducted on 125 patients. Fifty-six has diseases of the lungs, 16 of the mediastinum, 4 of the pleura, 17 of the liver, 2 of the pancreas, one of the spleen, 15 of the kidneys, 7 of the retroperineal space, two of the soft tissues, and 5 patients had diseases of the skeletal bones. Biopsy was combined with aspiration of the renal cyst content in 7 cases. The diagnostic value of biopsy under control of CT was 86% (106 cases); negative and pseudonegative results were recorded in 18 (14%) patients. The efficacy of biopsy is determined by such factors as the size of the lesion and the depth of its localization in the involved organ, the character of the pathological process and the region of its localization, the site from which the material is collected, and the needles used. Among 7 patients with therapeutic interventions, 5 had good and 2 had satisfactory immediate results. Complications were revealed in 4 (3.3%) patients, pneumothorax was encountered most frequently.

Computed tomography (CT) is used more and more often recently in the treatment of some surgical diseases of the internal organs. The subject of discussion in this work are the results of treatment of cysts and pyoinflammatory diseases of the internal organs. The work was conducted on CT IV generation "QUAD 1" of the CMS firm (England). Needles measuring 14-18d in diameter (Charrière scale) were used for aspiration. A total of 23 therapeutic interventions were performed in 19 patients with exudative pleurisy (1 patient), pleuritis (4), pulmonary abscesses (1), abscesses of the liver (1), abscesses of the subhepatic and subdiaphragmatic spaces (2), cysts of the liver (1) and kidneys (1 patient). Among the interventions 21 were aspirations and 2 drainage of the abscess. A mechanical syringe is used lately for more effective evacuation of the contents. The removed contents, ranging in volume from 10.0 to 600.0 ml, was subjected to cytological, biochemical, and bacteriological analysis. A single puncture is sufficient, as a rule, for aspiration of the cyst contents, one-stage aspiration from cysts of both kidneys may be conducted (as was the case in two of our patients). 96% alcohol was used as the sclerosing agent. In cases of small abscesses aspiration may be repeated for removal of the contents, irrigation of the cavity, and administration of antibiotics. In abscesses measuring more than 10 cm drainage is advisable. Control CT examination is conducted once a week. The condition of the cavity is appraised by combining CT with its contrast study. The immediate results were good and satisfactory in 17 (94.7%) patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Computed tomography (CT) examination was performed in 711 patients with various degenerative and dystrophic processes in the spine. The most numerous group (485 patients) included those with a posterior discal hernia associated in 54.3% of cases with other degenerative and dystrophic alterations in the vertebral column. The hernias were paramedial in 336 and central in 147 patients. In 98.4% of cases the lumbosacral portion was involved. The CT diagnosis was verified at surgery in 103 patients (21.3%) providing evidence for setting up the principal CT criteria of the hernia: deformity of the disk posterior margin in the form of its local prolapse, deformity of the epidural fat, presence of a soft tissue component, dislocation and deformity of the dural sac. It is established that CT is a safe and highly informative diagnostic procedure in discal hernias.