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Study of Ethanol Impact on the Transepidermal Transport of Indocyanine Green with Backscattering Spectroscopy

In the work, impact of aqueous 40%-ethanol solution on the transepidermal transport of photodynamic dye indocyanine green has been studied with backscattering spectroscopy. It has been first obtained the value of the dye diffusion coefficient through the stratum corneum ex vivo at the use of ethanol as a diffusion enhancer: (6.85±3.75)×10−7 cm2/s.

Processing and Visualization of Large Data Arrays in Taxonomic and Evolutionary Studies of Living Nature1 (a review)

A review is given of recent advances in the taxonomic study of organisms and current views on biological evolution and the origin of life. The steady increase in bioinformation resources is noted, which reflects the results of studies of the Earth’s biodiversity with the use of deciphered structures of biomacromolecules (DNA, RNA, proteins, etc.). This necessitates accounting for the specific character of manipulations with large data arrays, which is currently termed the big data problem.

Investigation of Mildronat ® Diffusion in Human Eye Sclera

Background and Objectives: Diseases of retina and optic nerve are the major causes of vision loss. The use of new drugs in the treatment of these diseases can reduce the decline of visual function due to the involvement of additional mechanisms of cell metabolism compensation. Thus, investigation of the drug diffusion in sclera is an important task at estimation of dose necessary for achievement of enough drug concentration in internal eye tissues.

Influence of the Hydrogen Bond on the IR-spectrum and Structure of Molecular Complex of Diamond Nanoparticles and DNA Bases

Background and Objectives: Using molecular modeling by the density functional theory method we analyze a hydrogen bonds formation and their influence on IR-spectrum and structure of molecular complex which is formed as the interaction of complementary couple of DNA nucleobases adenine and timin and nanodiamonds surrounded with carboxylic groups. As an example of nanodiamonds adamantine has been used. Intermolecular forces and structure of hydrogen bonds are investigated.

Investigation of Delay Time in Interaction between the Regulatory Circuits in the Cardiovascular System of Healthy Humans Using Modeling of Phase Dynamics

Background and Objectives: Low-frequency oscillations with a basic frequency of about 0.1 Hz are observed in the human heart rate and peripheral microcirculation. It is found out that these processes are self-oscillatory and interact between themselves. However, the details and characteristics of this interaction including the direction of coupling and delays in coupling functions are not well studied yet.

Applying Methods of Diffuse Light Scattering and Optical Trapping for Assessing Blood Rheological Parameters: Erythrocytes Aggregation in Diabetes Mellitus

Background and Objectives: Aggregation parameters of blood characterize red blood cells interaction processes which play a major role in the microcirculation regulation. It was shown that these parameters are significantly different in case of Diabetes Mellitus (DM) and therefore can be proposed as a novel parameter of the disease state and therapy efficiency.

Optical Clearing of Cranial Bone by Multicomponent Immersion Solutions and Cerebral Venous Blood Flow Visualization

Background and Objectives: Optical clearing of bone tissue is of great practical interest, which opens up the possibility of the development of minimally invasive laser diagnostics and brain therapy. The aim of this work is the study of the optical clearing of cranial bone using multicomponent optical clearing agents, and the possibility of the measurement of cerebral blood flow.

Optical Study of Blood Rheological Properties for Krushinsky – Molodkina Strain Rats with Diabetes Mellitus and Acute Disturbances of the Cerebral Circulation

Background and Objectives: The aim of the study was to assess the hemorheological parameters for rats with experimental diabetes and acute disturbances of the cerebral circulation.

Improved Data Processing Algorithm for Laser Ektacytometry of Red Blood Cells

Background and Objectives: Red blood cells deliver oxygen to organs and tissues. In case of tropical malaria, blood anemia, diabetes mellitus and many other diseases, the cells become corrupted. These pathologies lead in altering deformability of the cells, i.e ability to change their shape under external forces. Precise measurement of cell’s deformability gives important medical information which helps to cure and monitor the most wide spread diseases more effectively.

Monte Carlo Simulation of Laser Radiation Propagation in the Multilayers Model of Head and Brain Tissues in Health and in the Presence of Intracranial Hematoma

Background and Objectives: Development of new optical methods of non-contact express diagnostics of intracranial hematoma remains an actual task. The development of optical model of the head in norm and in the presence of intracranial hematoma is the aim of the present study. Influence of the dimensions of the head tissues with and without hematoma on distribution of the backscattered laser radiation intensity is discussed.

Investigation of the Interaction and Dynamics of Collagen and Collagenase Molecules in Solutions by Dynamic Light Scattering

Background and Objectives: Bacterial collagenase from Closrtidium histolyticum is widely used as a clinical tool in the nonsurgical treatment of Dupuytren’s disease in eye’s disorders treatment, for enzymatic debridement, for accelerated resorption of catgut sutures. Collagenase main feature is its ability to digest key protein of the animal extracellular matrix – collagen. Dynamic Light Scattering (DLS) technique allows for investigation of collagen and collagenase solutions in conditions close to physiological.

Albumin Conformational Changes During Glycation and Thermal Denaturation Processes Revealed by Fluorescence Spectroscopy and Small-angle X-ray Scattering

Background and Objectives: Objects of the research in this study are solutions of bovine serum albumin (BSA) and its aggregates. Structural changes of the protein molecules in solution with pH 3 and pH 7.4 are investigated during glycation and thermal denaturation processes, when the BSA molecules in solution undergo similar intermediate states. The main aim of the research is to compare structural changes of the BSA upon its glycation and thermal denaturation, revealed by combination of optical and X-ray techniques.

Leukocytes’ «Highlighting» Effect and its Application to Identify Blood Cells by Digital Microscopy Method

Objective: To find a way of identifying and counting of leukocytes in a native blood sample.

Materials and equipments: Whole donor blood sample, digital microscop.

Methods and approaches: The development of a method of leukocytes’ identification and counting for native blood samples was carried out on the basis of digital microscopy method.

ГЕНЕРАТОР АНИЩЕНКО-АСТАХОВА КАК ОДНА ИЗ БАЗОВЫХ МОДЕЛЕЙ ДЕТЕРМИНИРОВАННОГО ХАОСА

В обзоре формулируются условия возникновения хаотических автоколебаний и дается радиотехническая схема генератора, которая эти условия реализует. Выводятся уравнения генератора Анищенко-Астахова и проводится их анализ. Особое внимание уделяется взаимосвязи уравнений генератора с классическими моделями Теодорчика и Ван дер Поля.

НЕСТАЦИОНАРНОЕ ВОЗБУЖДЕНИЕ ОТКРЫТЫХ СТРУКТУР

Получены нестационарные электродинамические уравнения возбуждения открытых резонаторов и волноводных трансформаторов, основанные на методе функций Грина. Для открытого резонатора получены также аналогичные формулы, основанные на спектральном подходе. В общем виде задача о возбуждении сводится к интегральным уравнениям в пространственновременной области.

HETEROPHASE SEMICONDUCTORS UNDERACTION OF IRRADIATIONS

The history and current state of our heteropfiase photoconducting CdS-PbS films investigations are observed. Films were prepared by the vacuum evaporation method from the materials with limited mu tual solubility. Reasons of increased degradation stability with respect to radiation (in particular y- and electronic irradiations) are found out. Degradation stability is explained by diversion of recombination flow from wide-gap phase to narrow-gap. Radiation stimulated defects also move to narrow-gap phase.

Optical Doppler Methods for the Measurements of Flow Velocities of Biological Liquids

Background and Objectives: In this paper the key results obtained by the authors during the years of development of Doppler optical methods for quasi-elastic light scattering and coherence gating on biomedical liquids are presented. The research is focused on the sign sensitive velocity measurement and quantitative visualization of alternating and complex geometry flows using spectral approach to digital data processing of Doppler shift of the carrier frequency.

Estimation of Glucose Diffusion Coefficient in Human Dura Mater

Background and Objectives: Optical clearing of dura mater caused by hyperosmotic immersion liquids is important for the development of noninvasive methods of brain optical tomography and for the study of microcirculation and homeostasis of tissue fluids. It allows significantly increasing the spatial resolution and the probing depth of brain.

Study of Statistical Characteristics of GB-speckles, Forming at Scattering of Light on Virtual Structures of Nucleotide Gene Sequences of Enterobacteria

Background and Objectives: A brief review of methods of modern bioinformatics, based on the usage of virtual optical GBspeckles (gene-based speckles), has been presented in this paper. An algorithm of transformation of a nucleotide sequence into a 2D GB-speckle-structure has been proposed and discussed.

Mathematical Model of Vascular Tone Autoregulation

Background and Objectives: The conventional approach to study the blood circulat ion in the cardiovascular system of humans and animals is based on representation of the vascular system as a hierarchical structure of branching elastic tubes. While considerable progress has been achieved in the framework of this p aradigm, the other fails when one needs to analyze the dynamical patterns in networks of small arterial vessels.

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