And yet it moves: Recovery of volitional control after spinal cord injury

Preclinical and clinical neurophysiological and neurorehabilitation research has generated rather surprising levels of recovery of volitional sensory-motor function in persons with chronic motor paralysis following a spinal cord injury. The key factor in this recovery is largely activity-dependent plasticity of spinal and supraspinal networks. This key factor can be triggered by neuromodulation of these networks with electrical and pharmacological interventions. This review addresses some of the systems-level physiological mechanisms that might explain the effects of electrical modulation and how repetitive training facilitates the recovery of volitional motor control. In particular, we substantiate the hypotheses that: (1) in the majority of spinal lesions, a critical number and type of neurons in the region of the injury survive, but cannot conduct action potentials, and thus are electrically non-responsive; (2) these neuronal networks within the lesioned area can be neuromodulated to a transformed state of electrical competency; (3) these two factors enable the potential for extensive activity-dependent reorganization of neuronal networks in the spinal cord and brain, and (4) propriospinal networks play a critical role in driving this activity-dependent reorganization after injury. Real-time proprioceptive input to spinal networks provides the template for reorganization of spinal networks that play a leading role in the level of coordination of motor pools required to perform a given functional task. Repetitive exposure of multi-segmental sensory-motor networks to the dynamics of task-specific sensory input as occurs with repetitive training can functionally reshape spinal and supraspinal connectivity thus re-enabling one to perform complex motor tasks, even years post injury

ОСОБЛИВОСТІ ОБРАЗУ СІМ’Ї У ОСІБ, ХВОРИХ НА ШИЗОФРЕНІЮ

The features of the image of family in people with schizophrenia identified specific characteristics of this phenomenon, an attempt to substantiate the need for replacement of family therapy for this profile.Исследованы  особенности  образа  семьи  у  лиц,  страдающих  шизофренией. Выявлены специфические особенности данного феномена, сделана попытка обосно-вания необходимости восстановительной семейной терапии для пациентов данного профиля.Досліджено  особливості  образу  сім’ї  у  осіб,  хворих  на  шизофренію.  Виявлено специфічні характеристики даного феномену, зроблено спробу обґрунтувати необхідність відновлювальної сімейної психотерапії для хворих даного профілю

ЧИСЛЕННЫЙ АНАЛИЗ МАТЕМАТИЧЕСКИХ МОДЕЛЕЙ РАСПРЕДЕЛЕНИЯ ФАКТИЧЕСКИХ ВКЛАДОВ В НЕСИММЕТРИЮ И ОТКЛОНЕНИЕ НАПРЯЖЕНИЙ В ТОЧКАХ ОБЩЕГО ПРИСОЕДИНЕНИЯ СИСТЕМ ЭЛЕКТРОСНАБЖЕНИЯ

Purpose. Perform numerical analysis of the distribution of the factual contributions of line sources of distortion in the voltage distortion at the point of common coupling, based on the principles of superposition and exclusions. Methodology. Numerical analysis was performed on the results of the simulation steady state operation of power supply system of seven electricity consumers. Results. Mathematical model for determining the factual contribution of line sources of distortion in the voltage distortion at the point of common coupling, based on the principles of superposition and exclusions, are equivalent. To assess the degree of participation of each source of distortion in the voltage distortion at the point of common coupling and distribution of financial compensation to the injured party by all sources of distortion developed a one-dimensional criteria based on the scalar product of vectors. Not accounting group sources of distortion, which belong to the subject of the energy market, to determine their total factual contribution as the residual of the factual contribution between all sources of distortion. Originality. Simulation mode power supply system was carried out in the phase components space, taking into account the distributed characteristics of distortion sources. Practical value. The results of research can be used to develop methods and tools for distributed measurement and analytical systems assessment of the power quality.На основе имитационного моделирования проведен сравнительный анализ математических моделей распределения фактических вкладов линейных источников искажений в искажение напряжений в точке общего присоединения, которые основаны на принципах наложения и исключения. Полученные результаты позволили сделать вывод об эквивалентности двух математических моделей и их произвольном выборе для решения задачи распределения фактических вкладов линейных источников искажений в искажение напряжений в точке общего присоединения.На основі імітаційного моделювання проведено порівняльний аналіз математичних моделей розподілу фактичних внесків лінійних джерел спотворень у спотворення напруг у точці загального приєднання, які засновані на принципах накладення й виключення. Отримані результати дозволили зробити висновок про еквівалентність двох математичних моделей і їхній довільний вибір для розв’язання задачі розподілу фактичних внесків лінійних джерел спотворень у спотворення напруг у точці загального приєднання

КЛІНІКО-ЕПІДЕМІОЛОГІЧНІ ТА ЛАБОРАТОРНІ ОСОБЛИВОСТІ СУЧАСНОЇ БЕШИХИ

Despite the fact that erysipelas is a well-known infection, the incidence remains stable. The infection has a tendency to frequent relapses, which leads to the long-term incapacity of patients. The aim of the work – to establish the peculiarities of the current course of the erysipelas and the quality of life depending on the frequency of the infection based on the study of epidemiology, clinic, the severity of endogenous intoxication, the level of reactivity of the organism. Patients and methods. Inspection and research of medical records for 75 patients with erysipelas. Calculation of integrative indexes of endogenous intoxication and immunoreactivity. The SF-36 questionnaire was used for the assessment of the quality of life. The comparison group included 44 clinically and anamnestically healthy individuals. Results. The patients were divided into three groups with 25 people in each: with primary, repeated, and relapsing erysipelas. Women predominated among patients (78.7 %). The age was (54.2±4.1) years. The largest number of hospitalized people was detected in July-August. The course of the infection was moderate in 90.0 % of the cases. Erythematosus predominated among the clinical forms of disease (54 patients, 72.0 %). Indexes of non-specific reactivity and inflammation activity have a tendency to decrease in case of relapsing erysipelas (p<0.05–0.001). The indicator of the psychological health component for patients with primary (43.8±0.7) points and repeated (44.6±0.9)points forms of erysipelas was 12.0 % higher than those with a relapsing form of erysipelas – (38.9±1.2) points p<0.01. The parameters of the physical component for patients with primary and repeated forms of erysipelas were on the same level (respectively, (46.1±0.5) points) and (47.4±1.0) points, p>0.05). The lowest one was for patients with relapsing form of erysipelas (42.1±1.3) points p<0.05. Conclusions. A significant increase of the endogenous intoxication indexes and decrease of non-specific reactivity indexes were discovered in relapsing erysipelas compared to the primary erysipelas and control groups. The lowest indicators of the physical and psychological component of health were observed for patients with relapsing form of erysipelas.Незважаючи на те, що бешиха є давно відомою хворобою, захворюваність залишається стабільно високою. Хвороба, як і раніше, характеризується схильністю до частих рецидивів, що призводить до тривалої непрацездатності пацієнтів. Мета роботи – встановити особливості сучасної бешихи та якості життя залежно від частоти хвороби на підставі вивчення епідеміології, клініки, ступеня ендогенної інтоксикації, рівня реактивності організму. Пацієнти і методи. Обстежено і опрацьовано медичні карти 75 хворих на бешиху. Розраховано інте­г­ративні показники ендогенної інтоксикації та імунореактивності. Для оцінки якості життя був використаний опитувальник SF-36. Групу порівняння склали 44 здорові людини. Результати. Хворі були розділені на три групи: з первинною, з повторною, з рецидивною бешихою, по 25 осіб у кожній. Серед усіх хворих переважали жінки (78,7 %). Вік становив (54,2±4,1) роки. Найбільша кількість пацієнтів госпіталізована у серпні. Ступінь тяжкості хвороби у 90,0 % обстежуваних був середнім. Серед клінічних форм переважала еритематозна (54 хворих – 72,0 %). Індекси неспецифічної реактивності та активності запалення нижчі при рецидивній бешисі (р<0,05-0,001). Показник психологічного компонента здоров’я у пацієнтів з первинною (43,8±0,7 бала) та повторною (44,6±0,9 бала) формами бешихи на 12,0 % був вищим від осіб з рецидивною формою бешихи – (38,9±1,2) балів, р<0,01. Показники фізичного компонента у пацієнтів з первинною та повторною формами бешихи перебували на одному рівні (відповідно (46,1±0,5) бала та (47,4±1,0) бала, р>0,05), найнижчим він був у пацієнтів з рецидивною формою бешихи: (42,1±1,3) бала (р<0,05). Висновки. Встановлено статистично достовірне підвищення індексів ендогенної інтоксикації та зниження індексів неспецифічної реактивності при рецидивній бешисі відносно первинної бешихи та контрольної груп. Найнижчі показники фізичного та психологічного компонентів здоров’я спостерігалися у пацієнтів з рецидивною формою бешихи

Modeling of impact deformation processes of the ceramic container for radioactive waste storage

Results of researches in the field of designing containers for storage of radioactive materials are presented in the work. The purposes of researches include a development of an effective method of modeling static and dynamic deformation processes at shock impact on the ceramic container with radioactive materials at transportation. The next tasks have been solved: on the basis of the mathematical description of physic-mechanical processes of deformation of the complex design container has been chosen method of finite-element's for effective modeling of the stress-strain State of static and dynamic deformation processes in the containers made of ceramic elements; laws of deformation, estimations of durability and rigidity for designed containers have been received after calculations by means of the computer software; recommendations on perfection of a design of the container for maintenance of requirements to safety are given. Analysis Finite Element Method (FEM) has been conducted in the ANSYS system and results is presented

ОСОБЕННОСТИ ВЫБОРА БАТАРЕЙ КОНДЕНСАТОРОВ В ЭЛЕКТРИЧЕСКИХ СЕТЯХ С ИСТОЧНИКАМИ ИНТЕРГАРМОНИК

Purpose. Development of a methodology for selecting capacitor bank parameters designed to compensate for reactive power, if there are sources of interharmonics in the electrical network. Development of a methodology for selecting the parameters of capacitor banks that are part of resonant filters of higher harmonics and interharmonics. Methodology. For the research, we used the decomposition of the non-sinusoidal voltage (current) curve into the sum of the harmonic components with frequencies as multiple of the fundamental frequency - higher harmonics, and not multiple fundamental frequencies - interharmonics. Results. Expressions are obtained for checking the absence of inadmissible overloads of capacitor banks by voltage and current in the presence of voltage (current) in the curve, along with higher harmonics, of the discrete spectrum of interharmonics. When selecting capacitor banks, both for reactive power compensation and for filter-compensating devices, the necessity of constructing the frequency characteristics of the input and mutual resistances of the electrical network for analyzing possible resonant phenomena is confirmed. Originality. The expediency of simplified calculation of the voltage variation at the terminals of the banks of the capacitors of the higher harmonics filters and interharmonics due to the presence of the reactor in the filters is substantiated. Practical value. The use of the proposed approaches will make it possible to resolve a number of issues related to the choice of parameters of capacitor banks in networks with nonlinear loads, including: ensuring reliable operation of capacitor banks when their parameters deviate from their nominal values, as well as deviations in the parameters of the supply network and sources of harmonic distortion; ensuring the absence of resonant phenomena at frequencies of both higher harmonics and interharmonics.Разработана методика выбора батарей конденсаторов, применяемых как в качестве компенсаторов реактивной мощности при наличии источников интергармоник, так и в составе фильтров высших гармоник и интергармоник. Получены выражения для проверки отсутствия недопустимых перегрузок батарей конденсаторов по напряжению и по току при наличии в кривой напряжения (тока), наряду с высшими гармониками, дискретного спектра интергармоник. Обоснована целесообразность упрощенного учета изменения напряжения на зажимах батарей конденсаторов фильтров высших гармоник и интергармоник за счет наличия реактора в составе фильтров. Использование предложенных подходов позволит комплексно решать ряд вопросов, связанных с выбором параметров батарей конденсаторов в электрических сетях с нелинейными нагрузками

Electrophysiological Guidance of Epidural Electrode Array Implantation over the Human Lumbosacral Spinal Cord to Enable Motor Function after Chronic Paralysis.

Epidural electrical stimulation (EES) of the spinal cord has been shown to restore function after spinal cord injury (SCI). Characterization of EES-evoked motor responses has provided a basic understanding of spinal sensorimotor network activity related to EES-enabled motor activity of the lower extremities. However, the use of EES-evoked motor responses to guide EES system implantation over the spinal cord and their relation to post-operative EES-enabled function in humans with chronic paralysis attributed to SCI has yet to be described. Herein, we describe the surgical and intraoperative electrophysiological approach used, followed by initial EES-enabled results observed in 2 human subjects with motor complete paralysis who were enrolled in a clinical trial investigating the use of EES to enable motor functions after SCI. The 16-contact electrode array was initially positioned under fluoroscopic guidance. Then, EES-evoked motor responses were recorded from select leg muscles and displayed in real time to determine electrode array proximity to spinal cord regions associated with motor activity of the lower extremities. Acceptable array positioning was determined based on achievement of selective proximal or distal leg muscle activity, as well as bilateral muscle activation. Motor response latencies were not significantly different between intraoperative recordings and post-operative recordings, indicating that array positioning remained stable. Additionally, EES enabled intentional control of step-like activity in both subjects within the first 5 days of testing. These results suggest that the use of EES-evoked motor responses may guide intraoperative positioning of epidural electrodes to target spinal cord circuitry to enable motor functions after SCI

Electrical spinal stimulation, and imagining of lower limb movements to modulate brain-spinal connectomes that control locomotor-like behavior

© 2018 Gerasimenko, Sayenko, Gad, Kozesnik, Moshonkina, Grishin, Pukhov, Moiseev, Gorodnichev, Selionov, Kozlovskaya and Edgerton. Neuronal control of stepping movement in healthy human is based on integration between brain, spinal neuronal networks, and sensory signals. It is generally recognized that there are continuously occurring adjustments in the physiological states of supraspinal centers during all routines movements. For example, visual as well as all other sources of information regarding the subject's environment. These multimodal inputs to the brain normally play an important role in providing a feedforward source of control. We propose that the brain routinely uses these continuously updated assessments of the environment to provide additional feedforward messages to the spinal networks, which provides a synergistic feedforwardness for the brain and spinal cord. We tested this hypothesis in 8 non-injured individuals placed in gravity neutral position with the lower limbs extended beyond the edge of the table, but supported vertically, to facilitate rhythmic stepping. The experiment was performed while visualizing on the monitor a stick figure mimicking bilateral stepping or being motionless. Non-invasive electrical stimulation was used to neuromodulate a wide range of excitabilities of the lumbosacral spinal segments that would trigger rhythmic stepping movements. We observed that at the same intensity level of transcutaneous electrical spinal cord stimulation (tSCS), the presence or absence of visualizing a stepping-like movement of a stick figure immediately initiated or terminated the tSCS-induced rhythmic stepping motion, respectively. We also demonstrated that during both voluntary and imagined stepping, the motor potentials in leg muscles were facilitated when evoked cortically, using transcranial magnetic stimulation (TMS), and inhibited when evoked spinally, using tSCS. These data suggest that the ongoing assessment of the environment within the supraspinal centers that play a role in planning a movement can routinely modulate the physiological state of spinal networks that further facilitates a synergistic neuromodulation of the brain and spinal cord in preparing for movements

Spinal segment-specific transcutaneous stimulation differentially shapes activation pattern among motor pools in humans

Copyright © 2015 the American Physiological Society. Transcutaneous and epidural electrical spinal cord stimulation techniques are becoming more valuable as electrophysiological and clinical tools. Recently, we observed selective activation of proximal and distal motor pools during epidural spinal stimulation. In the present study, we hypothesized that the characteristics of recruitment curves obtained from leg muscles will reflect a relative preferential activation of proximal and distal motor pools based on their arrangement along the lumbosacral enlargement. The purpose was to describe the electrophysiological responses to transcutaneous stimulation in leg muscles innervated by motoneurons from different segmental levels. Stimulation delivered along the rostrocaudal axis of the lumbosacral enlargement in the supine position resulted in a selective topographical recruitment of proximal and distal leg muscles, as described by threshold intensity, slope of the recruitment curves, and plateau point intensity and magnitude. Relatively selective recruitment of proximal and distal motor pools can be titrated by optimizing the site and intensity level of stimulation to excite a given combination of motor pools. The slope of the recruitment of particular muscles allows characterization of the properties of afferents projecting to specific motoneuron pools, as well as to the type and size of the motoneurons. The location and intensity of transcutaneous spinal electrical stimulation are critical to target particular neural structures across different motor pools in investigation of specific neuromodulatory effects. Finally, the asymmetry in bilateral evoked potentials is inevitable and can be attributed to both anatomical and functional peculiarities of individual muscles or muscle groups