First order plus frequency dependent delay modeling : new perspective or mathematical curiosity?

The first-order-plus-dead-time model (FOPDT) is a popular simplified representation of higher order dynamics. However, a well known drawback is the rapid decrease of the frequency response accuracy with increasing process order. This especially applies to the higher frequency range. Literature offers solutions by extending this three parameter model with more parameters. Here, a fractional dead time is proposed. As such, a Frequency-Dependent Delay (FDD) is introduced, which offers a better approximation. As the fractional-order term introduces nonlinear coupling between the phase and the magnitude of the process, the fitting of the function becomes an iterative process, so a constrained multi-objective optimization is needed. This novel model, first-order-plus-frequency-dependent-delay or FOPFDD is fitted on a real electrical ladder network of resistors and capacitors of four and eight parts. The classic model, which is clearly a special case of the new model, is outperformed in the entire bandwidth

Mathematical modelling with experimental validation of viscoelastic properties in non-Newtonian fluids

The paper proposes a mathematical framework for the use of fractional-order impedance models to capture fluid mechanics properties in frequency-domain experimental datasets. An overview of non-Newtonian (NN) fluid classification is given as to motivate the use of fractional-order models as natural solutions to capture fluid dynamics. Four classes of fluids are tested: oil, sugar, detergent and liquid soap. Three nonlinear identification methods are used to fit the model: nonlinear least squares, genetic algorithms and particle swarm optimization. The model identification results obtained from experimental datasets suggest the proposed model is useful to characterize various degree of viscoelasticity in NN fluids. The advantage of the proposed model is that it is compact, while capturing the fluid properties and can be identified in real-time for further use in prediction or control applications. This article is part of the theme issue 'Advanced materials modelling via fractional calculus: challenges and perspectives'

Experimental and computational biomedicine : Russian Conference with International Participation in memory of Professor Vladimir S. Markhasin : abstract book

Toward 100 Anniversary of I. P. Pavlov's Physiological Society.The volume contains the presentations that were made during Russian conference with international participation "Experimental and Computational Biomedicine" dedicated to corresponding member of RAS V.S. Markhasin (Ekaterinburg, April 10‒12, 2016). The main purpose of the conference is the discussion of the current state of experimental and theoretical research in biomedicine. For a wide range of scientists, as well as for lecturers, students of the biological and medical high schools.Сборник содержит тезисы докладов, представленных на российской конференции с международным участием «Экспериментальная и компьютерная биомедицина», посвященной памяти члена‐корреспондента РАН В. С. Мархасина (г. Екатеринбург, 10‒12 апреля 2016 г.). Основной целью конференции является обсуждение современного состояния экспериментальных и теоретических исследований в области биомедицины. Сборник предназначен для ученых, преподавателей, студентов и аспирантов биологического и медицинского профиля.МАРХАСИН ВЛАДИМИР СЕМЕНОВИЧ (1941-2015)/ MARKHASIN VLADIMIR SEMENOVICH (1941-2015). [3] PROGRAMM COMMITTEE. [5] ORGANIZING COMMITTEE. [6] KEYNOTE SPEAKERS. [7] CONTENTS. [9] PLENARY LECTURES. [10] Fedotov S. Non-Markovian random walks and anomalous transport in biology. [10] Hoekstra A. Multiscale modelling in vascular disease. [10] Kohl P. Systems biology of the heart: why bother? [10] Meyerhans A. On the regulation of virus infection fates. [11] Panfilov A.V., Dierckx H., Kazbanov I., Vandersickel N. Systems approach to studying mechanisms of ventricular fibrillationusing anatomically accurate modeling. [11] Revishvili A.S. Atrial fibrillation. Noninvasive diagnostic and treatment:from fundamental studies to clinical practice. [12] Rice J. Life sciences research at IBM. [12] Roshchevskaya I.M., Smirnova S., Roshchevsky M.P. Regularities of the depolarization of an atria:an experimental comparative-physiological study. [12] Rusinov V.L., Chupahin O.N., Charushin V.N Scientific basis for development of antiviral drugs. [13] Solovyova O.E. Tribute Lecture. Mechano-electric heterogeneity of the myocardiumas a paradigm of its function. [13] Veksler V. Myocardial energy starvation in chronic heart failure:perspectives for metabolic therapy. [13] Wladimiroff J.W. Fetal cardiac assessment using new methodsof ultrasound examination. [14] Yushkov B.G., Chereshnev V.A. The important questions of regeneration theory. [14] EXPERIMENTAL AND COMPUTATIONAL MODELS IN CARDIOVASCULARPHYSIOLOGY AND CARDIOLOGY. [15] EXPERIMENTAL AND COMPUTATIONAL MODELS IN CARDIOVASCULARPHYSIOLOGY AND CARDIOLOGY. [15] Arteyeva N. T-wave area along with Tpeak-Tend interval is the most accurateindex of the dispersion of repolarization. [15] Borodin N., Iaparov B.Y., Moskvin A. Mathematical modeling of the calmodulin effect on the RyR2 gating. [15] Dokuchaev A., Katsnelson L.B., Sulman T.B., Shikhaleva E.V., Vikulova N.A. Contribution of cooperativity to the mechano-calcium feedbacksin myocardium. Experimental discrepancy and mathematicalapproach to overcome it. [16] Elman K.A., Filatova D.Y., Bashkatova Y.V., Beloschenko D.V. The stochastic and chaotic estimation of parametersof cardiorespiratory system of students of Ugra. [16] Erkudov V.O., Pugovkin A.P., Verlov N.A., Sergeev I.V., Ievkov S.A., Mashood S., Bagrina J.V. Characteristics of the accuracy of calculation of values of systemic blood pressure using transfer functions in experimental blood loss and its compensation. [16] Ermolaev P., Khramykh T.Mechanisms of cardiodepression after 80% liver resection in rats. [17] Filatova O.E., Rusak S.N., Maystrenko E.V., Dobrynina I.Y. Aging dynamics of cardio-vascular parameters аboriginal systemand alien population of the Russian North. [17] Frolova S., Agladze K.I., Tsvelaya V., Gaiko O. Photocontrol of voltage-gated ion channel activity by azobenzenetrimethylammonium bromide in neonatal rat cardiomyocytes. [18] Gorbunov V.S., Agladze K.I., Erofeev I.S. The application of C-TAB for excitation propagation photocontrolin cardiac tissue. [18] Iribe G. Localization of TRPC3 channels estimated by in-silicoand cellular functional experiments. [19] Kachalov V.N., Tsvelaya V., Agladze K.I. Conditions of the spiral wave unpinning from the heterogeneitywith different boundary conditions in a model of cardiac tissue. [19] Kalita I., Nizamieva A.A., Tsvelaya V., Kudryashova N., Agladze K.I. The influence of anisotropy on excitation wave propagationin neonatal rat cardiomyocytes monolayer. [19] Kamalova Y. The designing of vectorcardiograph prototype. [20] Kapelko V., Shirinsky V.P., Lakomkin V., Lukoshkova E., Gramovich V.,Vyborov O., Abramov A., Undrovinas N., Ermishkin V. Models of chronic heart failure with acute and gradual onset. [20] Khassanov I., Lomidze N.N., Revishvili A.S. Remote Patient Monitoring and Integration of Medical Data. [20] Kislukhin V. Markov chain for an indicator passing throughoutcardio-vascular system (CVS). [21] Konovalov P.V., Pravdin S., Solovyova O.E., Panfilov A.V. Influence of myocardial heterogeneity on scroll wave dynamicsin an axisymmetrical anatomical model of the left ventricle of thehuman heart. [21] Koshelev A., Pravdin S., Ushenin K.S., Bazhutina A.E. An improved analytical model of the cardiac left ventricle. [22] Lookin O., Protsenko Y.L. Sex-related effects of stretch on isometric twitch and Ca2+ transientin healthy and failing right ventricular myocardiumof adult and impuberal rats. [22] Moskvin A. Electron-conformational model of the ligand-activated ion channels. [22] Nezlobinsky T., Pravdin S., Katsnelson L.B. In silico comparison of the electrical propagation wave alongmyocardium fibers in the left ventricle wall vs. isolation. [23] Nigmatullina R.R., Zemskova S.N., Bilalova D.F., Mustafin A.A., Kuzmina O.I., Chibireva M.D., Nedorezova R.S. Valid method for estimation of pulmonary hypertention degreein children. [23] Parfenov A. Mathematical modeling of the cardiovascular systemunder the influence of environmental factors. [24] Pimenov V.G., Hendy A. Adaptivity of the alternating direction method for fractional reactiondiffusion equation with delay effects in electrocardiology. [24] Podgurskaya A.D., Krasheninnikova A., Tsvelaya V., Kudryashova N., Agladze K.I. Influence of alcohols on excitation wave propagationin neonatal rat ventricular cardiomyocyte monolayer. [24] Pravdin S. A mathematical model of the cardiac left ventricle anatomy and morphology. [24] Seemann G. Cause and effects of cardiac heterogeneity:insights from experimental and computational models. [25] Seryapina A.A., Shevelev O.B. Basic metabolomic patterns in early hypertensive rats: MRI study. [25] Shestakov A.P., Vasserman I.N., Shardakov I.N. Modeling of cardiac arrhythmia generation caused bypathological distribution of myocardial conductivity. [26] Shutko A.V., Gorbunov V.S., Nizamieva A.A., Guriya K.G., Agladze K.I. Contractile micro-constructs from cardiac tissue culturefor the research of autowave propagation in excitable systems. [26] Simakov S., Gamilov T., Kopylov Ph. Computational study of the haemodynamic significanceof the stenosis during multivessel coronary disease. [27] Syomin F., Zberiya M.V. A numerical simulation of changes in the performance of the leftventricle of the heart under various hemodynamic conditions. [27] Tsaturyan A. A simple model of cardiac muscle:mechanics, actin-myosin interaction and Ca-activation. [27] Tsvelaya V., Krasheninnikova A., Kudryashova N., Agladze K.I. Calcium-current dominated upstroke in severe hyperkalemia. [28] Ushenin K.S., Pravdin S., Chumarnaya T.V., Alueva Y.S., Solovyova O.E. Dynamics of scroll wave filaments in personalized modelsof the left ventricle of the human heart. [28] Vasserman I.N., Shardakov I.N., Shestakov A.P. Deriving of macroscopic intracellular conductivity of deformedmyocardium based on its microstructure. [28] Vassilevski Y.V., Pryamonosov R., Gamilov T. Personalized 3D models and applications. [29] Zun P.S., Hoekstra A., Anikina T.S. First results of fully coupled 3D models of in-stent restenosis. [29] BIOMECHANICS. EXPERIMENTAL AND MATHEMATICAL MODELSSBIOMECHANICS. EXPERIMENTAL AND MATHEMATICAL MODELS. EXPERIMENTAL AND MATHEMATICAL MODELS. [30] Balakin A., Kuznetsov D., Protsenko Y.L. The ‘length-tension’ loop in isolated myocardial preparations of theright ventricle of normal and hypertrophied hearts of male rats. [30] Belousova M.D., Kruchinina A.P., Chertopolokhov V.A. Automatic control model of the three-tier arm type manipulatorin the aimed-movement task. [30] Berestin D.K., Bazhenova A.E., Chernikov N.A., Vokhmina Y.V. Mathematical modeling of dynamics of development of Parkinson'sdisease on the tremor parameters. [31] Dubinin A.L., Nyashin Y.I., Osipenko M.A. Development of the biomechanical approach to tooth movementunder the orthodontic treatment. [31] Galochkina T., Volpert V. Reaction-diffusion waves in mathematical model of bloodcoagulation. [31] Golov A.V., Simakov S., Timme E.A. Mathematical modeling of alveolar ventilationand gas exchange during treadmill stress tests. [32] Gurev V., Rice J. Strain prediction in 3D finite element models of cardiac mechanics. [32] Kamaltdinov M.R. Simulation of digestion processes in antroduodenum:food particles dissolution in consideration of functional disorders. [33] Khamzin S., Kursanov A., Solovyova O.E. Load-dependence of the electromechanical function of myocardiumin a 1D tissue model. [33] Khokhlova A., Iribe G., Solovyova O.E Transmural gradient in mechanical properties of isolatedsubendocardial and subepicardial cardiomyocytes. [33] Kruchinin P.A. Optimal control problem and indexesof stabilometric "test with the visual step input". [34] Kruchinina A.P., Yakushev A.G. A study of the edge segments of saccadic eye trajectory. [34] Kursanov A., Khamzin S., Solovyova O.E. Load-dependence of intramyocardial slow force responsein heterogeneous myocardium. [35] Lisin R.V., Balakin A., Protsenko Y.L. Experimental study of the intramyocardial slow force response. [35] Melnikova N.B., Hoekstra A. The mechanics of a discrete multi-cellular model of arterial in‐stent restenosis. [35] Murashova D.S., Murashov S.A., Bogdan O.P., Muravieva O.V., Yugova S.O. Modelling of soft tissue deformation for static elastometry. [36] Nikitin V.N., Tverier V.M., Krotkikh A.A. Occlusion correction based on biomechanical modelling. [36] Nyashin Y.I., Lokhov V.A. Development of the “Virtual physiological human” concept. [37] Shulyatev A.F., Akulich Y.V., Akulich A.Y., Denisov A.S. 3D FEA simulation of the proximal human femur. [37] Smoluk A.T., Smoluk L.T., Balakin A., Protsenko Y.L., Lisin R.V. Modelling viscoelastic hysteresis of passive myocardial sample. [37] Svirepov P.I. Mathematical modeling of the left atria mechanical actionwith mitral regurgitation. [38] Svitenkov A., Rekin O., Hoekstra A. Accuracy of 1D blood flow simulations in relation to level of detailof the arterial tree model. [38] Tsinker M. Mathematical modelling of airflow in human respiratory tract. [39] Wilde M.V. Influence of artificial initial and boundary conditionsin biomechanical models of blood vessels. [39] ELECTROPHYSIOLOGY. EXPERIMENTAL AND COMPUTATIONAL MODELS. CLINICAL STUDIES. [40] Agladze K.I., Agladze N.N. Arrhythmia modelling in tissue culture. [40] Golovko V., Gonotkov M.A. Pharmacological analysis of transmembrane action potential'smorphology of myoepitelial cells in the spontaneously beating heartof ascidia Styela rustica. [40] Gonotkov M.A., Golovko V. The crucial role of the rapidly activating component of outwarddelayed rectifier K-current (IKr) in pig sinoauricular node (SAN). [40] Danilov A.A. Numerical methods for electrocardiography modelling. [41] Kolomeyets N.L., Roshchevskaya I.M. The electrical resistivity of a segment of the tail, lungs, liver,intercostal muscles of grass snakes during cooling. [41] Kharkovskaia E., Zhidkova N., Mukhina I.V., Osipov G.V. Role of TRPC1 channels in the propagation of electrical excitationin the isolated rat heart. [42] Lubimceva T.A., Lebedeva V.K., Trukshina M.A., Lyasnikova E.A., Lebedev D.S. Ventricular lead position and mechanical dyssynchronyin response to cardiac resynchronization therapy. [42] Poskina T.Y., Shakirova L.S., Klyus L.G., Eskov V.V. Stochastics and chaotic analysis of electromyogramand electroencefalogramm. [42] Prosheva V.I. New insights into the pacemaker and conduction systemcells organization in the adult avian heart. [43] Suslonova O., Smirnova S., Roshchevskaya I.M. Cardioelectric field in rats with experimental pulmonaryhypertension during ventricular depolarization. [43] Syunyaev R.A., Karpaev A.A., Aliev R.R. Simulation of the fibroblasts effect on synchronizationand rhythmogenesis in the sinoatrial node. [44] Zorin N.M., Ryvkin A.М., Moskvin A. Cooperation of membrane and calcium oscillatorsin sinoatrial node cells. [44] EXPERIMENTAL AND COMPUTATIONAL MODELS IN IMMUNOLOGY. [45] Bocharov G. Systems approach to modelling the "virus-host organism" interactionin infectious diseases. [45] Brilliant S.A. Impact of immobilization stress on change of protein fractionshemoglobin of bone marrow in rats. [45] Bykova M. The features of biochemical properties of extracellular matrix of bonemarrow in rats in conditions which stimulate granulocytopoiesis. [45] Chigvintsev V.M. A mathematical model of the functioning and mutual regulation ofthe immune and neuroendocrine systems in response to viralexposure under the impact of environmental factors, taking intoaccount the evolution of synthetic function impairment. [46] Khramtsova Y. The role of mast cells in the regulation of repair testicles. [46] Novikov M.Y., Kim A.V. Simulation of immune processes using Bio-Medical Software Package. [47] Polevshchikov A.V., Bondar A.V., Gumovskaya J.P. Modelling of t cell extravasation into a lymph node:from morphological basics towards clonal selection theory. [47] Tuzankina I.A., Sarkisyan N., Bolkov M., Tihomirov L.B., Bass E.A. Oral and maxillofacial manifestationsof primary immunodeficiency syndroms. [47] Zaitsev S.V., Polevshchikov A.V. Evaluation of probabilities of antigen recognition by T-lymphocytesin the lymph node: a mathematical model. [48] MOLECULAR BASIS OF BIOLOGICAL MOTILITY. [49] Bershitsky S.Y., Nabiev S., Kopylova G., Shchepkin D., Matyushenko A.M., Koubassova N.A., Levitsky D.I., Tsaturyan A. Mutations in the central part of tropomyosin molecule affectthe actomyosin interaction. [49] Borovkov D.I., Kopylova G., Shchepkin D., Nabiev S., Matyushenko A.M., Levitsky D.I. Functional studies of tropomyosin mutations associatedwith dilated and hypertrophic cardiomyopathy. [49] Fatkhrakhmanova M.R., Mukhutdinova K.A., Kasimov M.R., Petrov A.M. The role of glutamate NMDA-receptor-NO synthase axis in the effectof 24-hydroxycholesterolon synaptic vesicle exocytosis at the mouseneuromuscular junctions. [50] Gritsyna Y., Vikhlyantsev I.M., Salmov N., Bobylev A.G., Podlubnaya Z.A. Increasing μ-calpain activity in striated muscles of alcohol-fed rats. [50] Kochubey P.V., Bershitsky S.Y. Study of biphasic tension rise in contracting muscle fiberduring ramp stretch. [51] Kopylova G., Shchepkin D., Nabiev S., Nikitina L., Bershitsky S.Y. The Ca2+ regulation of actin-myosin interactionin atrium and ventricle. [51] Nabiev S., Bershitsky S.Y., Tsaturyan A. Measurements of the bending stiffnessof reconstructed thin filament with the optical trap. [51] Shchepkin D., Kopylova G., Matyushenko A.M., Popruga K.E., Pivovarova A.V., Levitsky D.I. Structural and functional studies of tropomyosin species withcardiomyopathic mutations in the areaof tropomyosin-troponin contact. [52] Shenkman B., Nemirovskaya T.L., Lomonosova Y.N., Lyubimova K.A., Ptitsyn K.G. Nitric oxide in uloaded muscle: powerless guard of stability. [52] Shirinsky V.P., Kazakova O.A., Samsonov M.V., Khalisov M.M., Khapchaev A.Yu., Penniyaynen V.A., Ankudinov A.V., Krylov B.V.Spatiotemporal activity profiling of key myosin regulators inendothelial cells with regard to control of cell stiffnessand barrier dysfunction. [53] Yakupova E.I., Bobylev A.G., Vikhlyantsev I.M., Podlubnaya Z.A. Smooth muscle titin forms aggregates with amyloid-likedye-binding properties. [53] MEDICAL BIOINFORMATICS. [54] Eskov V.M., Khadartsev A.A., Gavrilenko T.V., Filatov M.A. Homeostasis and the evolution of complex biological systems. [54] Gorbunov D.V., Garaeva G.R., Sinenko D.V., Grigorenko V.V. Limit of applicability the theorem of Glansdorf-Prigoginein the describing homeostatic systems. [54] Iaparov B.Y., Moskvin A., Solovyova O.E. Electron-conformational transformations governthe temperature dependence of the RYR2 gating. [54] Lookin N. Towards to the bio-computer: from serial von Neumann architectureto systolic computer system in one chip. [55] Obesnyuk V.F. Hybrid technology of cohort rate of conditionallifetime risk trend assessment. [55] Parshin D.V., Cherevko A., Chupakhin A., Orlov K., Ufimtseva I., Krivoshapkin A. Analytical methods for diagnostics of cerebral aneurysms. [56] Rudenko E., Shchegolev B. Parathyroid hypertensive factor (PHF) - β2-adrenergic receptorpotential antagonist. [56] Ryvkin A.М., Moskvin A. Probabilistic theory of ions binding to RYR-channelwithin the improved electron-conformational model. [56] Shadrin K.V., Pakhomova V., Rupenko A. Stoichiometric modeling of oxygen transport through the surfaceof the isolated perfused rat liver at various oxygenation conditions. [57] Zubarev A.Y. Theoretical modelling of magnetic hyperthermia. [57] TRANSLATIONAL MEDICINE. FROM BASIC SCIENCE TO CLINICAL PRACTICE. [58] Blinkova N.B., Danilova I.G., Gette I.F., Abidov M.T., Pozdina V.A. Features of the regenerative processesin the rat liver exposed to alloxan diabetes with stimulationof macrophages functional activity. [58] Bulavintseva T.S., Danilova I.G., Brilliant S.A. The response of macrophage to chronic hyperglycemiabefore and after modulation of macrophage functional phenotype. [58] Chumarnaya T.V., Alueva Y.S., Kochmasheva V.V., Mikhailov S.P., Ostern O.V., Sopov O.V., Solovyova O.E. Specific features of the functional geometryof the left ventricle in myocardial diseases. [59] Kolobov A.V., Kuznetsov M.B., Simakov S., Gorodnova N. Multiscale modeling of angiogenic tumor growth and progression. [59] Maryakhina V.S., Ovechkin M.V., Spirina V.I. Laser flash photolysis in investigation of breast cancerat different stages of tumor development. [59] Nikitina E.A., Zhuravlev A.V., Zakharov G.A., Medvedeva A.V., Dolgaya Y.F., Ivanova P.N., Tokmacheva E.V., Savvateeva-Popova E.V. Genetic and epigenetic aspectsof neurodegenerative diseases etiopathogenesis. [60] Pichugova S.V., Komarova S.Y., Beykin Y.B. Electron microscopy in the diagnosis of male infertility. [60] Pyankova Z.A., Medvedeva S.Y., Gette I.F., Belousova A.V. Influence of the pericellular microenvironmentto the functional liver cells damaged by toxin. [61] Smirnyh S.E., Chereshneva M.V., Danilova I.G.The dynamics of the regenerative processes in the retina in rats withalloxan diabetes and after injectionof tetrahydrophthalazine derivatives. [61] Solodushkin S.; Stolyar A. Mathematical modelling of the kidney transplant outcomes. [62] Tsyvian P.B. Hemodynamics and regulation of angiogenesis in human embryoconceived by in vitro fertilization. [62] Zotova N. Methodological approaches to identificationof Systemic Inflammation under sepsis. [62] MEDICAL CHEMISTRY[64] Bozhko Y., Bakhtin V.M., Belokonova N.A. On correction and prevention of magnesium deficiency. [64] Chernaya L.V., Kovalchuk L.A., Nokhrina E.S., Nikonov G.I. Biological active trace elements of medicinal leeches Hirudomedicinalis L., 1758 and Hirudo verbana Carena, 1820, grown inartificial conditions of regional biofactories in Russia. [64] Emelianov V.V., Savateeva E.A., Sidorova L.P., Tseitler T.A., Gette I.F., Bulavintseva T.S., Smirnyh S.E., Danilova I.G., Maksimova N.E., Mochulskaya N.N., Chupakhin O.N., Chereshnev V.A. 1,3,4-thiadiazine derivates – antioxidants and protein glycationblockers – for correction of experimental diabetes mellitus. [65] Gagarin I., Tonkushina M.O., Ostroushko A.A., Grzhegorzhevskii K.V. Modelling of {Mo72Fe30} electrophoresis. [65] Kurgina T.A., Anarbaev R.O., Lavrik O.I. Poly(ADP-ribose)polymerase 1 is one of the targetsfor the anti-cancer drugs search. [66] Sapozhnikova I.M., Deeva E.G., Konovalova N.I. Synthesis and antiviral activity of nitrile-containing1,2,4-triazolo [5,1-c]-1,2,4-triazines. [66] Savateev K. New perspective series of adenosine receptors inhibitors. [66] Tarkhanova A.E., Kovalchuk L.A. The estimate of the concentrations of macroelements and traceelements in the biological system of obese pregnant women: (bloodof mother – placenta – blood of newborn babies). [67] Tonkushina M.O., Ostroushko A.A., Gagarin I. Associates of Mo72Fe30. [67] Trebukhov A.V., Shirmanova E.A., Trebuhov A.V. The study of the effects of L-arginine and taurine-contains drugs onplatelet aggregation performance and lipid metabolism in patientswith heart diseases. [68] Voinkov E. Nitroacetonitrile is the intermediatefor the synthesis of azolo-6-azapurines. [68] BIOMEDICAL TECHNOLOGY. [69] Balashov V.A., Agladze K.I., Agapov I.I., Efimov A.E. The study of cardiomyocyte structureby scanning probe nanotomography. [69] Chibireva M.D. Development of the way of early diagnosticof essential arterial hypertension different forms in adolescents. [69] Ivanov V.Y., Antsygin I.N., Sedunova I.Н., Myshkina A.V Training for biomedical engineering at the Ural Federal University. [70] Klyueva Y. CD45RA+ T-lymphocytes levels evaluation

Bioimpedance sensor and methodology for acute pain monitoring

The paper aims to revive the interest in bioimpedance analysis for pain studies in communicating and non-communicating (anesthetized) individuals for monitoring purpose. The plea for exploitation of full potential offered by the complex (bio)impedance measurement is emphasized through theoretical and experimental analysis. A non-invasive, low-cost reliable sensor to measure skin impedance is designed with off-the-shelf components. This is a second generation prototype for pain detection, quantification, and modeling, with the objective to be used in fully anesthetized patients undergoing surgery. The 2D and 3D time-frequency, multi-frequency evaluation of impedance data is based on broadly available signal processing tools. Furthermore, fractional-order impedance models are implied to provide an indication of change in tissue dynamics correlated with absence/presence of nociceptor stimulation. The unique features of the proposed sensor enhancements are described and illustrated here based on mechanical and thermal tests and further reinforced with previous studies from our first generation prototype

MICRONEEDLE-ASSISTED TRANSDERMAL DELIVERY OF NALTREXONE SPECIES: \u3cem\u3eIN VITRO\u3c/em\u3e PERMEATION AND \u3cem\u3eIN VIVO\u3c/em\u3e PHARMACOKINETIC STUDIES

Naltrexone (NTX) is a drug used primarily in the management of alcohol dependence and opioid dependence. Based on several drawbacks associated with the oral and injectable intramuscular dosage forms of naltrexone currently available on the market, there is substantial interest in delivering naltrexone transdermally. Although naltrexone does not permeate skin at the rate sufficient to reach therapeutic plasma concentrations in humans, novel flux enhancement methods such as microneedles help address this challenge. Earlier work in humans has demonstrated that the use of microneedles achieves plasma concentrations in the lower end of expected therapeutic values. Further flux enhancement is desired to decrease the patch area while increasing drug transport rates. In the present work, several strategies aiming at in vitro flux maximization were employed including: formulation optimization, naltrexone salt screening, and naltrexone prodrug design. While naltrexone prodrugs did not reveal any improved permeation characteristics formulation optimization through decrease in vehicle microviscosity allowed a 5-fold increase in the percutaneous transport rates, and naltrexone glycolate salt selection provided an additional 1.5-fold enhancement in flux. One of the key observations was a good correlation (R2 = 0.99) between vehicle microviscosity and drug transport rates across the microchannel pathway. This finding alone allowed for formulation optimization and, at the same time, provided a potential explanation for the low permeation of high-concentration naltrexone salts and prodrugs. In vivo studies were carried out in Yucatan minipigs using a “poke and patch” microneedle method to deliver NTX•HCl. These studies demonstrated that initial plasma concentrations spiked to 2.5 ng/ml but rapidly dropped to a plateau of below 1 ng/ml. This pharmacokinetic profile could be explained by the use of a mathematical model which identified the importance of microchannel closure kinetics on drug transport. Also, an estimate of diffusional resistance of the viable tissue associated with percutaneous NTX•HCl delivery through microchannels was obtained. Its relatively large value suggests that the effect of diffusional resistance of the dermis in vivo should not be ignored and must be accounted for in order to obtain a good in vitro-in vivo correlation

Dermic diffusion and stratum corneum: a state of the art review of mathematical models

Transdermal biotechnologies are an ever increasing field of interest, due to the medical and pharmaceutical applications that they underlie. There are several mathematical models at use that permit a more inclusive vision of pure experimental data and even allow practical extrapolation for new dermal diffusion methodologies. However, they grasp a complex variety of theories and assumptions that allocate their use for specific situations. Models based on Fick's First Law found better use in contexts where scaled particle theory Models would be extensive in time-span but the reciprocal is also true, as context of transdermal diffusion of particular active compounds changes. This article reviews extensively the various theoretical methodologies for studying dermic diffusion in the rate limiting dermic barrier, the stratum corneum, and systematizes its characteristics, their proper context of application, advantages and limitations, as well as future perspectives

Proton diffusion spectroscopy and modeling of brain metabolism at 14.1T

As a field at the CIBM, Nuclear magnetic resonance (NMR)spectroscopy can be applied non-invasively to explore the metabolic fate of energy fuel substrates, as well as the rate at which they are consumed, using 13C and 1H nuclei. The work of this thesis encompasses both nuclei, and focuses on (1) improving the quantification and modeling of glucose-derived metabolites; and (2) characterizing diffusion-related parameters of the purportedly glial-specific energy substrate, acetate. Both aim to quantitatively explore cerebral energy metabolism, at ultra-high magnetic field, in vivo, in the healthy rat. 13C NMR spectroscopy, as a tool, enables measuring the progressive incorporation of 13C-glucose into brain glucose and then NMR detectable amino acids (glutamate and glutamine); this relies on the infusion of the 13C-labeled energy substrate. The experimentally obtained 13C labelling curves are analyzed using suitable mathematical models to provide an estimation of cerebral metabolic rates. Here, a dynamic model of time-courses of 13C multiplets arising from isotopomers was considered. So beyond the two-compartment neuronal-glial model, we took into account additional data on the dynamics of 13C isotopomers, available from the fine structure multiplets in 13C spectra of glutamate and glutamine, measured under prolonged [1-6,13C] glucose infusion. We concluded that the dynamic analyses of 13C multiplet time courses of glutamate and glutamine resulted in a higher precision for estimating the absolute values of most cerebral metabolic rates. Acetate metabolism is challenging because dynamic metabolic modeling requires prior knowledge of the transport and uptake kinetics of infused acetate. We sought this information by determining the apparent concentration and distribution volume (V_d) of cerebral acetate between the intracellular and the extracellular compartments. Experimentally, the diffusion characteristics of cerebral acetate were measured, relative to that of N-Acetylaspartate (NAA, known to be mainly intracellular) using diffusion-weighted 1H NMR spectroscopy at 14.1T, under prolonged acetate infusion. The detection of an acetate and NAA signal at large diffusion weighting provided direct experimental evidence of intracellular cerebral acetate and NAA, although a substantial fraction of acetate was extracellular. To estimate the apparent concentration of in vivo brain acetate, T1 and T2 relaxation times of acetate were measured. The longer T1 relaxation and shorter T2 relaxation times of acetate compared with NAA provided evidence of its small molecular size, and possibly different chemical environment. Our experimentally determined value of V_dled to cerebral metabolic rates of acetate (CMR acetate) of the same order reported for the glial Krebâs cycle rate, an indication that estimates of CMR acetate are highly dependent on V_d. Finally, in order to pursue metabolic mapping of cerebral acetate uptake in the rat, in vivo, at 14.1 T, the design and construction of a combined transmit-birdcage coil and receive-quadrature pair surface coil was considered. Its performance was compared to a single birdcage coil in the transmit/receive mode. So far, the preliminary results of the 2-coil configuration are promising: homogenous excitation and a gain in sensitivity up to a distance of 5 mm are achievable. Improvements are ongoing for NMR spectroscopic and imaging applications at 14.1 T