57 research outputs found
The reconstruction of three-dimensional models from MR-images for solving problems of radiation therapy
The Magnetic Resonance Imaging (MRI) is popular medical diagnostic technique. Digital Imaging and COmmunications in Medicine (DICOM) is a standard and contains a series of planar images (MRI results). The paper examines the problems of the development of methods for the construction of 3D voxel models of human organs by data obtained using MRI. These models can be used for the research needed for non-invasive methods of treatment. The achievement of this work is a prototype software package, designed for medical physics research
РЕГИОНАЛЬНЫЕ ЭКОЛОГИЧЕСКИЕ И СОЦИАЛЬНО-ЭКОНОМИЧЕСКИЕ АСПЕКТЫ ЗАБОЛЕВАЕМОСТИ ПОДРОСТКОВОГО НАСЕЛЕНИЯ В УСЛОВИЯХ ПРОЖИВАНИЯ В ПРОМЫШЛЕННЫХ ЦЕНТРАХ
It is presented the characteristic changes of atmospheric air pollution and morbidity of adolescents aged 15-17 years living in urban environments with different specificity of industrial enterprises for the 10-year period. We investigated the relationship dynamics of the indicators of the health of modern teenagers with socio-economic indicators of regional development. A predictive model for the regression rate of absolutely healthy adolescents (group healt I) is worked out and set the share of influence on this indicator factors included in the regression model. Представлена характеристика изменений загрязнения атмосферного воздуха и показателей заболеваемости подростков в возрасте 15–17 лет, проживающих в условиях города с различной спецификой промышленных предприятий за 10-летний период. Исследована связь динамики показателей здоровья современных подростков с социально-экономическими показателями регионального развития. Разработана регрессионная прогностическая модель для показателя числа абсолютно здоровых подростков (I группа здоровья), установлен удельный вес влияния на данный показатель факторов, вошедших в регрессионную модель.
Spin-polarized current amplification and spin injection in magnetic bipolar transistors
The magnetic bipolar transistor (MBT) is a bipolar junction transistor with
an equilibrium and nonequilibrium spin (magnetization) in the emitter, base, or
collector. The low-injection theory of spin-polarized transport through MBTs
and of a more general case of an array of magnetic {\it p-n} junctions is
developed and illustrated on several important cases. Two main physical
phenomena are discussed: electrical spin injection and spin control of current
amplification (magnetoamplification). It is shown that a source spin can be
injected from the emitter to the collector. If the base of an MBT has an
equilibrium magnetization, the spin can be injected from the base to the
collector by intrinsic spin injection. The resulting spin accumulation in the
collector is proportional to , where is the proton
charge, is the bias in the emitter-base junction, and is the
thermal energy. To control the electrical current through MBTs both the
equilibrium and the nonequilibrium spin can be employed. The equilibrium spin
controls the magnitude of the equilibrium electron and hole densities, thereby
controlling the currents. Increasing the equilibrium spin polarization of the
base (emitter) increases (decreases) the current amplification. If there is a
nonequilibrium spin in the emitter, and the base or the emitter has an
equilibrium spin, a spin-valve effect can lead to a giant magnetoamplification
effect, where the current amplifications for the parallel and antiparallel
orientations of the the equilibrium and nonequilibrium spins differ
significantly. The theory is elucidated using qualitative analyses and is
illustrated on an MBT example with generic materials parameters.Comment: 14 PRB-style pages, 10 figure
РАДИКАЛЬНАЯ КОРРЕКЦИЯ СЛОЖНОГО ВРОЖДЕННОГО ПОРОКА СЕРДЦА У ПАЦИЕНТА С ВНЕПЕЧЕНОЧНОЙ ФОРМОЙ ПОРТАЛЬНОЙ ГИПЕРТЕНЗИИ
Aim. To present rare clinical observation of successful surgical treatment of the patient with double-chamber right ventricle in combination with ventricular septal defect, subaortic fi brosis and muscular stenosis, insufficiency of the aortic valve and extrahepatic portal hypertension.Description. Patient F., 15 years old, was diagnosed with Congenital Heart Disease – double-chambered right ventricle, ventricular septal defect. Fibromuscular subaortic stenosis. Aortic valve insuffi ciency II. Circulatory failure II A., functional class III. Extrahepatic portal hypertension. Splenomegaly. Thrombocytopenia. The state after the imposition of splenorenal anastomosis in September 1998 and the imposition of mesocaval H-shaped anastomosis in 1998. Non-functioning anastomoses. Patient indicated for surgical correction of CHD, however, given the low level of platelets, expressed splenomegaly, leucopenia, the patient was referred for a preliminary treatment to Rogachev’s Pediatric Hematology, Oncology and Immunology Center. The treatment (stimulating thrombopoiesis using romiplostim) gave no signifi cant effect. Platelet count reached 70–90 Å~ 109. Seeing of frequent bleeding from esophageal varices, the patient underwent varix sclerosis. At the time of hospitalization – no esophageal varices. The patient appealed to V.I. Shumakov Federal Research Center of Transplantology and Artifi cial Organs where he was recommended for surgical treatment.Result. The patient performed surgery: radical correction of CHD: resection of the stenosis of the outfl ow tract of the right ventricle, subaortic stenosis resection, closure of ventricular septal defect, AV plasty under cardiopulmonary bypass. The early postoperative period was uneventful. Leukopenia was observed to 1,2 Å~ 109, thrombocytopenia 70–90 Å~ 109. Despite the low level of platelets bleeding in pre-and postoperative period was not registered. Antibiotic therapy with tienam. Good postoperative results were obtained. Liver function was not affected.Conclusion. Presented clinical case demonstrates the possibility of surgical intervention of combined heart disease with cardiopulmonary bypass in patient with extrahepatic portal hypertension.Цель. Представить редкое клиническое наблюдение успешного хирургического лечения пациента с двухкамерным правым желудочком в сочетании с дефектом межжелудочковой перегородки, субаортальным фиброзно-мышечным стенозом, недостаточностью аортального клапана и внепеченочной формой портальной гипертензии.Описание. Больной Ф.,15 лет, диагноз: «врожденный порок сердца – двухкамерный правый желудочек, дефект межжелудочковой перегородки; субаортальный фиброзно-мышечный стеноз; недостаточность аортального клапана II ст.; недостаточность кровообращения II А, функциональный класс III; внепеченочная форма портальной гипертензии; спленомегалия; тромбоцитопения». Состояние после наложения спленоренального анастомоза в сентябре 1998 г. и наложения мезентерикокавального Н-образного анастомоза в 1998 г. Нефункционирующие анастомозы. Пациенту была показана хирургическая коррекция ВПС, однако, учитывая низкий уровень тромбоцитов, выраженную спленомегалию, лейкопению, пациент был направлен для предварительного лечения в ФНКЦ детской гематологии, онкологии и иммунологии им. Д. Рогачева. Проведенное лечение (стимуляция тромбоцитопоэза при помощи ромиплостима) – без значительного эффекта. Достигнут уровень тромбоцитов 70–90 × 109. В связи с частыми кровотечениями из ВРВ пищевода пациенту выполнено их склерозирование. На момент госпитализации ВРВ пищевода отсутствовали. Пациент обратился в ФГБУ «ФНЦТИО им. акад. В.И. Шумакова», где было рекомендовано оперативное лечение.Результат. Пациенту выполнено оперативное вмешательство – радикальная коррекция порока: резекция стеноза выходного отдела правого желудочка, резекция субаортального стеноза, ушивание дефекта межжелудочковой перегородки, пластика АК в условиях искусственного кровообращения. Ранний послеоперационный период протекал без осложнений. Отмечалась лейкопения до 1,2 × 109, тромбоцитопения 70–90 × 109. Несмотря на низкий уровень тромбоцитов, кровотечений в пред- и послеоперационном периоде не отмечалось. Антибиотикотерапия тиенамом. Получен хороший послеоперационный результат. Функция печени не пострадала.Заключение. Представленный клинический случай демонстрирует возможность выполнения оперативного вмешательства сложного порока сердца в условиях искусственного кровообращения у пациента с внепеченочной портальной гипертензией
Accuracy improvement of cloning area detection
In the work the modification of a method of detection and localization of regions of the integrity violation in the digital image obtained as a result of cloning is developed. Aim: The aim of the work is to increase the accuracy of detection of integrity violation regions of the digital image by development of modification of a method of detection and localization of cloning regions based on the block oriented approach due to simultaneous use in case of expertize of the image with square, triangular, round blocks and of irregular shape blocks. Materials and Methods: Further development of the block oriented approach to the solution of problem of cloning results detection in digital image is provided. Modification of the method of detection and localization of the cloning regions developed by authors earlier, based on the accounting of closeness of the matrix blocks which is quantitatively evaluated by means of different variants of the metrics assignment is offered. Results: The technique of simultaneous use of square, triangular, round blocks and blocks of irregular shape in case of the expertize of the image based on the block oriented approach is developed. Providing the computational experiment the accuracy increase of determination of integrity violation regions of the digital image when using of the offered modification of the method of detection and localization of fields of cloning in case of simultaneous use in case of expertize of different partitioning types blocks is set: the relative value of the area of the revealed region from real region of a clone increases by 1.6 times in comparison with results of operation of algorithmic implementation of the method taken as a basis
Method of photomontage detection under conditions of limitations absence for photos falsification
The widespread using of fake pictures in information wars, lawsuits, politics, etc., needs to develop new detection methods of photomontage. One of them is a method of photomontage detection based on the analysis of singular values of matrix blocks of digital images. Aim: The aim of this research is to check the application area of photomontage detection method based on analysis of singular values of matrix blocks of digital images in the absence of restrictions on the degree of their compression. Materials and Methods: The basis of this method is the detection of the differences between the images when they have different degrees of compression: values of the zero singular values matrix of blocks corresponding to foreign part of image. We distinguish this area on the background of the main image, that allows to detect falsification. The mentioned method was investigated under certain restrictions imposed on the used test photos. An advanced experiment with images was held, for which there are no restrictions on the degree of compression. Results: The falsification was detected in 44.4% of cases in experimental study while saving the digital image after photomontage in lossless format, and in 53.3% of cases when saving the losses. Montage was detected most often when the difference between the quality factor Q of the main image and the replacing area was more than two
Characteristics of current challenges, risks and uncertainties in the field of natural resource management
Modern challenges, environmental risks and economic uncertainties in the field of natural resource management in the Urals and Western Siberia are considered. Information relating to the regional changes in the soil surface (air) temperature, the state of the cryolitic zone of the forest and swamp ecosystems, and extreme uncertainties is presented
Surgical management of neurologically complicated kyphoscoliosis using transposition of the spinal cord: Case report
Background: Transposition of the spinal cord made it possible to achieve mobilization of the fixed kyphoscoliosis, significantly increase spinal canal volume and improve spinal canal shape. This helped to eliminate spinal cord compression and achieve complete regression of the existing neurological symptoms.
Methods and results: We report the clinical case of surgical management of neurologically complicated kyphoscoliotic deformity of the thoracic spine by transposition of the spinal cord and correction using posterior segmental spinal instrumentation.
Conclusions: The required correction of severe kyphoscoliosis was performed; the risks of trunk imbalance, deformity progression, and instrumentation failure in the long-term postoperative period were reduced.
Level of evidence: Level IV – 1 case
- …