Experimental studies of direct-drive, low-intensity, low-adiabat spherical implosions on OMEGA

This paper presents both theoretical and experimental studies of the stability of dynamic interaction between a feedback controlled manipulator and a passive environment. Necessary and sufficient conditions for “coupled stability”—the stability of a linear, time-invariant n-port (e.g., a robot, linearized about an operating point) coupled to a passive, but otherwise arbitrary, environment—are presented. The problem of assessing coupled stability for a physical system (continuous time) with a discrete time controller is then addressed. It is demonstrated that such a system may exhibit the coupled stability property; however, analytical, or even inexpensive numerical conditions are difficult to obtain. Therefore, an approximate condition, based on easily computed multivariable Nyquist plots, is developed. This condition is used to analyze two controllers implemented on a two-link, direct drive robot. An impedance controller demonstrates that a feedback controlled manipulator may satisfy the coupled stability property. A LQG/LTR controller illustrates specific consequences of failure to meet the coupled stability criterion; it also illustrates how coupled instability may arise in the absence of force feedback. Two experimental procedures—measurement of endpoint admittance and interaction with springs and masses—are introduced and used to evaluate the above controllers. Theoretical and experimental results are compared.

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Tracking Control of Robot Manipulators Using a Robust Deterministic Control Law

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2801499 ◽

1998 ◽

Vol 120 (4) ◽

pp. 537-541 ◽

Cited By ~ 3

Author(s):

C.-G. Kang ◽

R. Horowitz ◽

G. Leitmann

Keyword(s):

Dynamic Systems ◽

Tracking Control ◽

Robot Manipulators ◽

Experimental Studies ◽

Control Law ◽

Direct Drive ◽

Control Scheme ◽

Deterministic Control ◽

Two Degree Of Freedom ◽

Theoretical Developments

There have been theoretical developments on the control of dynamic systems based on deterministically uncertain and singularly perturbed models in recent years. In this paper, a robust deterministic control scheme proposed originally by M. Corless et al. is modified, and is applied to the tracking control of robot manipulators. Simulation and experimental studies for a two degree of freedom, direct drive SCARA manipulator are conducted to evaluate the effectiveness of the control scheme.

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LOW-INTENSITY SIGNAL MODULATION OF THE MICROWAVE PHYSIOTHERAPY EQUIPMENT

Bulletin of National Technical University of Ukraine Kyiv Polytechnic Institute Series Instrument Making ◽

10.20535/1970.61(1).2021.237107 ◽

2021 ◽

pp. 77-84

Author(s):

Oleksii Yanenko ◽

Serhii Peregudov ◽

Konstantin Shevchenko ◽

Vasyl Kychak

Keyword(s):

Second Harmonic ◽

Selection Process ◽

Mode Selection ◽

Experimental Studies ◽

Control Unit ◽

External Source ◽

Absorption Capacity ◽

Signal Modulation ◽

Low Intensity ◽

Microwave Therapy

The article describes the features of the amplitude and frequency modulation of the output signals of millimeter range generators for microwave therapy. A review of the appearance of possible biological and medical effects using modulated signals is carried out. The use of highly sensitive radar-type equipment made it possible to study the absorption capacity of a person in the mm-wave range from an external source. The authors’s results of experimental studies are described, this are showed that at some frequencies, an increased absorption of the power of the irradiating signal is recorded. These frequencies are referred to as “absorption resonances”. The original schemes of monochromatic and noise signal generators developed by the authors are presented, and the principle of their operation is described. The article shows the possibility of generating low-intensity signals and ensuring the generator range operation using the second harmonic of the monochromatic signal and the selective properties of the EHF nodes. The technical parameters and characteristics of the developed devices are revealed. The application areas of the developed devices in practical medicine are out-lined. With the help of the control unit, a low-frequency signal as a saw-like or triangular voltage is generated and is supplied to the varactor converter. Under the influence of the modulation signal, the varactor capacitance changes, and, therefore, the frequency of the EHF generator. The operation of a combined radiation measurement system with a modulated noise-like output spectrum and the patient feedback is described. The article demonstrates the broad practical possibilities for using microprocessor technology for automation and control of the operation mode selection process, for the formation and change of the microwave signal modulation parameters. The conducted studies reveal the process of interaction of low-intensity microwave radiation with the human body and can be used in technologies of millimeter therapy. The article describes the service functions of the developed equipment, which contribute to its more effective use in microwave therapy technologies.

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Evaluation of histological changes in peri-implant bone tissue after ultrasound application at early healing stages

Stomatologist Minsk ◽

10.32993/stomatologist.2018.3(30).1 ◽

2018 ◽

pp. 38-42 ◽

Cited By ~ 1

Author(s):

S.P. Rubnikovich ◽

I.S. Khomich

Keyword(s):

Bone Tissue ◽

Dental Implants ◽

Morphological Changes ◽

Experimental Studies ◽

Low Frequency ◽

Control Group ◽

Pulsed Ultrasound ◽

Low Intensity Pulsed Ultrasound ◽

Low Intensity ◽

Dental Implantation

The aim was to study the nature of the morphological changes over time in the bone tissue around the implants under the influence of low-intensity pulsed ultrasound in the experiment. Materials and methods. Experimental studies were carried out on rabbits of the chinchilla breed, with dental implants installed in the tibia – two experimental groups with ultrasound and one control group. The animals were withdrawn from the experiment at 1, 2, 4 and 8 weeks and histological examination of the sections of peri-implant tissues was carried out. Results. The processes of osseointegration of dental implants in all groups of animals occurred without disrupting the normal process sequence. In the early stages granulation tissue is formed, later it is replaced by fibrous-reticular and coarse-fibrous bone tissue, and at the end – by a more mature lamellar bone tissue. However, the timing and degree of maturation of bone tissue, as well as osseointegration of implants in groups using low-frequency low-intensity pulsed ultrasound and without it differed significantly. The study showed that ultrasound exposure to implants and surrounding tissues induces osteoreparation processes, stimulating neoangiogenesis in granulation and newly formed bone tissue. Conclusion. Application of ultrasound to implants and subsequent application to the peri-implant tissues during and after dental implantation promotes the formation of bone tissue, identical by the histostructure to the maternal bone.

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MORPHOFUNCTIONAL PARAMETERS OF CATTLE ERYTHROCYTES UNDER STRESS AND ITS CORRECTION BY LOW-INTENSITY LASER RADIATION

Vestnik of the Russian agricultural science ◽

10.30850/vrsn/2021/1/67-71 ◽

1970 ◽

pp. 67-71

Author(s):

М. N. Ivashchenko ◽

А. V. Deryugina ◽

P. S. Ignatiev ◽

V. B. Metelin ◽

М. N. Talamanova ◽

...

Keyword(s):

Laser Radiation ◽

Erythrocyte Membrane ◽

Control Level ◽

Experimental Studies ◽

Erythrocyte Membranes ◽

Physical Factors ◽

Low Intensity ◽

Intensity Laser ◽

Technological Stress

The study investigated the content of malondialdehyde (MDA), the electrophoretic mobility of erythrocytes (EPME), the spectrum of erythrocyte membrane proteins and the morphology of cattle erythrocytes in in vitro experiments under stress and exposure to low-intensity laser radiation (LLLT). Clinical and experimental studies carried out in the last decade indicate the possibility of modulating the organism adaptive reactions when exposed to such physical factors as low-intensity laser radiation. The work showed that the effect of LLLT on the blood of stressed animals caused the restoration of the studied parameters to the level of physiological norms, while in animals that underwent technological stress, EPME was reduced by 31%, MDA concentration was increased by 65%. The effect of LLLT on the blood of unstressed animals did not lead to a change in EPME and MDA concentration. The study of the protein spectrum of erythrocyte membrane of animals subjected to technological stress revealed that the content of spectrin decreased by 16%, glycophorin C increased by 35%, the morphology of erythrocytes after stress was characterized by an increase in the number of echinocytes, stomatocytes and degeneratively altered erythrocytes. Under the LLLT action on the cow erythrocytes after stress there was a restoration of the morphology of cells and the content of proteins of erythrocyte membranes to the control level.

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MODELS OF BIOMODULATION IN A MICROPROCESSOR SYSTEM OF SUPER LOW INTENSIVE MICROWAVE RADIATION, INTENDED FOR TRANSFORMATION OF BRAIN NEURODYNAMIC ACTIVITY AND MODIFICATION OF THE FUNCTIONAL STATE OF THE PATIENT

СИСТЕМНЫЙ АНАЛИЗ И УПРАВЛЕНИЕ В БИОМЕДИЦИНСКИХ СИСТЕМАХ ◽

10.36622/vstu.2021.20.1.022 ◽

2021 ◽

pp. 160-168

Author(s):

Феликс Андреевич Пятакович ◽

Ольга Владимировна Мевша ◽

Татьяна Игоревна Якунченко ◽

Кристина Феликсовна Макконен

Keyword(s):

Microwave Radiation ◽

Functional State ◽

Clinical Medicine ◽

Interdisciplinary Collaboration ◽

Power Level ◽

Experimental Studies ◽

Physical Nature ◽

Microprocessor System ◽

Low Intensity ◽

The Brain

Еще в 60-70 годы XX-го столетия в экспериментальных исследованиях новосибирских ученых, выполненных под руководством академика В.П.Казначеева, была установлена роль сверхслабых физических полей в развитии цитопатологического действия биологических объектов вирусной природы, агентов химической и физической природы. В последние годы в экспериментальной и клинической медицине наряду с использованием низкоинтенсивных крайне высокочастотных миллиметровых излучений (менее 10 мВт/см) успешно используют СВЧ генераторы сверхнизкой интенсивности сантиметрового диапазона длин волн на уровне мощности, не превышающих 10 мкВт/см. Подобное СВЧ излучение сверхмалой мощности, осуществляемое на частоте колебаний кластеров воды первого порядка, способствует нормализации процессов метаболизма. Настоящее исследование выполнено в соответствии с планами проблемной комиссии по «хронобиологии и хрономедицине» РАН. На основе междисциплинарного сотрудничества была сформирована виртуальная команда исследователей работающих в разных университетах страны и включавшая математиков, системных программистов, инженеров и врачей-исследователей. При этом для реализации целей и задач исследования использовалась, так называемая, линейная модель движения потока информации из научной лаборатории в клиническую практику (from bench to bedside). В связи с чем, нами был реализован проект, направленный на разработку технической системы модульного типа, предназначенной для генерации СВЧ излучения с заданными свойствами. В микроконтроллере СВЧ генератора был запрограммирован цифровой аналог сигналов отражающих нейродинамические процессы мозга. В настоящей статье показана электрофизиологическая эффективность сверхнизко интенсивных излучений сантиметрового диапазона длин волн модулированных низкочастотными сигналами подобных ритму ЭЭГ и с циклической изменяемостью скважности. В клинических исследованиях у больных сахарным диабетом II с сопутствующей гипертонической болезнью на основе теста Спилбергера показана трансформация патологической нейродинамической активности мозга с последующей модификацией функционального состояния пациента. Рассмотрены результаты не эффективного воздействия, эффективного воздействия и успешного воздействия с изменениями динамики уровня пластичности нейродинамической активности мозга Back in the 60s-70s of the 20th century, in the experimental studies of Novosibirsk scientists, carried out under the leadership of Academician V.P. Kaznacheev, the role of super weak physical fields in the development of the cytopathological action of biological objects of viral nature, agents of chemical and physical nature was established. In recent years, in experimental and clinical medicine, along with the use of low-intensity extremely high-frequency millimeter radiation (less than 10 mW / cm), microwave generators of super low intensity of the centimeter wavelength range have been successfully used at a power level not exceeding 10 μW/cm. Such super low-power microwave radiation, is realized at the frequency of vibrations of first-order water clusters, contributes to the normalization of metabolic processes. The present study was work out in accordance with the plans of the problem commission on "chronobiology and chronomedicine" of the Russian Academy of Sciences. On the basis of interdisciplinary collaboration, a virtual team of researchers working in different universities in the country was formed and included mathematicians, systems programmers, engineers and medical researchers. At the same time, to implement the goals and objectives of the study, the so-called linear model of the flow of information from the scientific laboratory to clinical practice (from bench to bedside) was used. In this connection, we have implemented a project aimed at developing a modular-type technical system designed to generate microwave radiation with desired properties. In the microcontroller of the microwave generator, a digital analogue of signals reflecting the neurodynamic processes of the brain was programmed. This article shows the electrophysiological efficiency of super-low-intensity radiation in the centimeter range of wavelengths modulated by low-frequency signals similar to the EEG rhythm. In experimental studies in patients with diabetes mellitus II with concomitant hypertension, the transformation of the pathological neurodynamic activity of the brain with the subsequent modification of the patient's functional state has been shown. The results of ineffective influence, effective influence and successful influence with changes in the dynamics of the level of plasticity of neurodynamic activity of the brain are considered

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Human Extenders

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2899068 ◽

1993 ◽

Vol 115 (2B) ◽

pp. 281-290 ◽

Cited By ~ 97

Author(s):

H. Kazerooni ◽

Jenhwa Guo

Keyword(s):

Degrees Of Freedom ◽

Experimental Studies ◽

Mathematical Expression ◽

Contact Forces ◽

Degree Of Freedom ◽

Direct Drive ◽

Physical Strength ◽

Dynamics And Control ◽

And Performance ◽

And Control

A human’s ability to perform physical tasks is limited by physical strength, not by intelligence. We coined the word “extenders” as a class of robot manipulators worn by humans to augment human mechanical strength, while the wearer’s intellect remains the central control system for manipulating the extender. Our research objective is to determine the ground rules for the control of robotic systems worn by humans through the design, construction, and control of several prototype experimental direct-drive/non-direct-drive multi-degree-of-freedom hydraulic/electric extenders. The design of extenders is different from the design of conventional robots because the extender interfaces with the human on a physical level. The work discussed in this article involves the dynamics and control of a prototype hydraulic six-degree-of-freedom extender. This extender’s architecture is a direct drive system with all revolue joints. Its linkage consists of two identical subsystems, the arm and the hand, each having three degrees of freedom. Two sets of force sensors measure the forces imposed on the extender by the human and by the environment (i.e., the load). The extender’s compliances in response to such contact forces were designed by selecting appropriate force compensators. The stability of the system of human, extender, and object being manipulated was analyzed. A mathematical expression for the extender performance was determined to quantify the force augmentation. Experimental studies on the control and performance of the experimental extender were conducted to verify the theoretical predictions.

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Efficiency of ademethionine in oxidative stress in tissues of irradiated rats

Journal of Education, Health and Sport ◽

10.12775/jehs.2021.11.06.021 ◽

2021 ◽

Vol 11 (6) ◽

pp. 192-198

Author(s):

G. F. Stepanov ◽

L. O. Tereshchenko ◽

E. V. Oleinik ◽

G. S. Maryniuk ◽

O. I. Budalenko ◽

...

Keyword(s):

Total Dose ◽

Control Level ◽

Experimental Studies ◽

Living Organism ◽

Reduction Factor ◽

Low Doses ◽

Pyridine Nucleotides ◽

Γ Irradiation ◽

Low Intensity ◽

Reduced Forms

Introduction. Ionizing radiation in low doses of low intensity causes prolonged activation of lipid per oxidation and depletion of the antioxidant system in a living organism. Moreover, Ademethionine is currently being considered as a promising antioxidant.Method. Experimental studies were carried out on 60 sexually mature male Wistar rats. The animals were irradiated in a total dose of 1Gy on a γ-therapeutic device AGAT-R No. 83 (isotope 60Co). At the end of the total dose, the rats were injected intraperitoneally with Heptral (ademethionine) after 15 minutes, 12, 24, 36, 48, 60, 72, 84, 96, 108, 120, 132, 144, 156 hours after radiation exposure at the rate of 10 mg / kg mass. After the introduction of Heptral, the animals were taken into the experiment after 24 hours, 3, 7, 15 days. In homogenates of the spleen and thymus of animals, the amount of oxidized and reduced forms of pyridine nucleotides was determined.Results. Chronic γ-irradiation in a total dose of 1Gy leads to a significant decrease in the content of reduced forms of pyridine nucleotides in the spleen and thymus of rats. Administration of Heptral to irradiated animals normalized oxidative homeostasis. So, on the 7th day of the experiment, the amount of oxidized forms of pyridine nucleotides in the spleen was 47.3% lower, and reduced - 36.3% higher than in animals that did not receive treatment. At the end of the observation period, the reduction coefficient of pyridine nucleotides in the spleen slightly differed from the control level. In comparison with irradiated animals, which were not injected with Heptral, the NADP content was lower by 70.3%, and NADPH2 - higher by 48.8%.Conclusion. The course administration of Heptral to irradiated animals leads to the normalization of the reduction factor of pyridine nucleotides. According to its mechanism of action, Heptral can be used in the complex treatment of low- intensity radiation injuries in low doses.

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THE USE OF LOW-INTENSITY RADIATION IN TREATMENT OF PERIODONTAL TISSUE DISEASES (LITERATURE REVIEW)

Ukrainian Dental Almanac ◽

10.31718/2409-0255.3.2021.01 ◽

2021 ◽

pp. 5-13

Author(s):

E.M. Danko ◽

Ye.Ya. Kostenko ◽

S.B. Kostenko ◽

V.V. Pantyo

Keyword(s):

Laser Radiation ◽

Soft Tissues ◽

High Efficiency ◽

Periodontal Diseases ◽

Experimental Studies ◽

Periodontal Tissue ◽

Photodynamic Treatment ◽

Periodontal Tissues ◽

Low Intensity ◽

Intensity Radiation

Topic relevance. Periodontal tissue diseases currently take a significant place among infectious diseases, both in dentistry and in medicine in general. Traditional methods of treatment of inflammatorydystrophic periodontal diseases do not bring the desired results, so the question arises of finding alternative, non-drug treatments. Among such means, special attention is paid to the use of various types of low-intensity radiation, as well as the cumulative effect of light and photosensitizers. The aim of the study is to analyze literary sources regarding the use of various types of low-intensity radiation in the treatment of periodontal tissue diseases. Materials and methods. The research and analysis of scientific literature on the basis of Google Scholar, Research Gate, Wiley Online Library and Academia.edu on the use of various types of radiation in the treatment of periodontal tissue diseases was carried out. Results and discussion. Laser radiation shows anti-inflammatory, antimicrobial, immunomodulatory and desensitizing effect, stimulates tissue reparation, and also reduces histohemmatic barriers in the inflammatory process, reduces gum hyperemia, which indicates the high efficiency of this method in optimizing the processes of restoring periodontal structures. With wavelengths of 630 and 870 nm, laser radiation at certain parameters increases the sensitivity of S. aureus and P.aeruginosa to commonly used antibiotics. With long-term exposure, PILER (polychromatic polarized incoherent low-energy radiation) has a similar effect on soft tissues, which improves the results of treatment of chronic catarrhal gingivitis in complex therapy, activates regenerative processes, reduces the spread and pain, normalizes immune processes. Polychromatic and monochromatic PILER shows a pronounced antimicrobial effect against opportunistic pathogens, although complete data on its use in periodontology is not yet available. LED radiation, in turn, also increases the sensitivity of conditionally pathogenic microorganisms to some antibiotics, causes improvement of oral hygiene indicators, bleeding of gums and stabilization of tooth mobility, inhibits the activation of pro-inflammatory cytokins, has a biostimulating effect on gum fibroblast and antiinflammatory effect. Experimental studies show that the use of low-intensity radiation and photosensitizers for photodynamic treatment (PDT) show significant improvement of treatment outcomes in periodontal patients. Thus, PDT in combination with mechanical cleaning of periodontal pockets leads to a significant decrease in their depth compared to traditional treatment methods. Conclusion. Application of various methods of irradiation of periodontal tissues using a certain dose of low-intensity radiation, wavelength and exposure, both individually and in combination with photosensitizers, can be employed in the treatment of inflammatory and inflammatory-dystrophic periodontal diseases as an effective antimicrobial method.

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Intracranial Sonodynamic Therapy With 5-Aminolevulinic Acid and Sodium Fluorescein: Safety Study in a Porcine Model

Frontiers in Oncology ◽

10.3389/fonc.2021.679989 ◽

2021 ◽

Vol 11 ◽

Author(s):

Luca Raspagliesi ◽

Antonio D’Ammando ◽

Matteo Gionso ◽

Natasha D. Sheybani ◽

Maria-Beatriz Lopes ◽

...

Keyword(s):

Brain Tissue ◽

Aminolevulinic Acid ◽

Malignant Gliomas ◽

Experimental Studies ◽

Sodium Fluorescein ◽

Periventricular White Matter ◽

Large Animal ◽

Sonodynamic Therapy ◽

Low Intensity

BackgroundSonodynamic therapy (SDT) is an emerging ultrasound-based treatment modality for malignant gliomas which combines ultrasound with sonosensitizers to produce a localized cytotoxic and modulatory effect. Tumor-specificity of the treatment is achieved by the selective extravasation and accumulation of sonosensitizers in the tumor-bearing regions. The aim of this study is to demonstrate the safety of low-intensity ultrasonic irradiation of healthy brain tissue after the administration of FDA-approved sonosensitizers used for SDT in experimental studies in an in vivo large animal model.MethodsIn vivo safety of fluorescein (Na-Fl)- and 5 aminolevulinic acid (5-ALA)-mediated low-intensity ultrasound irradiation of healthy brain parenchyma was assessed in two sets of four healthy swine brains, using the magnetic resonance imaging (MRI)-guided Insightec ExAblate 4000 220 kHz system. After administration of the sonosensitizers, a wide fronto-parietal craniotomy was performed in pig skulls to allow transmission of ultrasonic beams. Sonication was performed on different spots within the thalamus and periventricular white matter with continuous thermal monitoring. Sonication-related effects were investigated with MRI and histological analysis.ResultsPost-treatment MRI images acquired within one hour following the last sonication, on day one, and day seven did not visualize any sign of brain damage. On histopathology, no signs of necrosis or apoptosis attributable to the ultrasonic treatments were shown in target areas.ConclusionsThe results of the present study suggest that either Na-FL or 5-ALA-mediated sonodynamic therapies under MRI-guidance with the current acoustic parameters are safe towards healthy brain tissue in a large in vivo model. These results further support growing interest in clinical translation of sonodynamic therapy for intracranial gliomas and other brain tumors.

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