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Optical Absorption and Raman Scattering in Doped Crystals TlGaSe2 and TlInS2

Background and Objectives. The TlGaSe2 and TlInS2 monocrystals are the А3В3С6 2 type ternary semiconductor compounds. Studies of TlGaSe2 and TlInS2 materials are carried out quite intensively due to the uniqueness of their optical and electrophysical properties and significant prospects for their practical use. At the same time, information about the effect of specific doping impurities on the properties of such materials is insufficient and often contradictory.

Intermolecular Interaction in Two-component Compounds of Nanodiamonds and Doxorubicin

Background and Objectives: Detonation nanodiamond (ND) is one of the most promising materials for targeted drug delivery – one of rapidly developing areas of modern chemistry, pharmacology and medicine. Wide possibilities of surface modification and advantageous dimensions make nanodiamonds very attractive objects for using in the drug delivery process. A number of studies have shown that therapeutic efficacy of drugs is enhanced and their toxicities may be attenuated with immobilization on the enriched ND. There are a lot of drug immobilization methods on ND surfacy.

Methods of Autodyne Interferometry of the Distance by Injected Current Modulation of a Semiconductor Laser

Background and Objectives: Two methods of distance interferometry for two types of wave modulation of laser radiation have been presented. The methods of triangular and harmonic wave modulation of a signal have been described. The advantages of the triangular wave modulation method in combination with the use of the frequency of the self-mixing signal spectrum, as well as the advantages of the harmonic wave modulation method in combination with the use of the amplitudes of the self-mixing signal spectrum have been shown.

A Hybrid Approach in Modeling of Statistical Characteristics of Multiple Scattered Light

Background and Objectives: A hybrid approach to modeling of the statistical characteristics of multiple scattered light in application to optical probes of random media is considered. The approach is based on recovery of the probability density of path lengths for partial components of a scattered light field in a probed medium using approximate analytical methods or the numerical simulation.

Difference-Frequency Generator and Optical Parametric Oscillator Pumped by a Semiconductor Disk Laser: Comparative Study with a Time Delay Model

Background and Objectives: High-resolution spectroscopy is known to need sources of coherent radiation in the mid- and farinfrared spectral bands. Sources based on optical nonlinear interaction (a difference-frequency generator and an optical parametric oscillator) are known to be almost ideally suitable for an application. Intracavity realizations of the devices with a nonlinear crystal located in the cavity, can likely be made simple, compact and easy to use.

Interpretation of IR and Raman Spectra of Albumin

Object and purpose of work: The subject of the study is bovine serum albumin (BSA). The aim of the work is to give an interpretation of the vibrational spectra of BSA aqueous solution in the region of ~1700–600 cm– 1. Methods: In this regard the experimental measurement of the IR and Raman spectra of BSA and the calculation of vibrational spectra of zwitterionic ion forms 20 amino acids and their dipeptides were carried out. The effect of anharmonicity and intermolecular interaction (IMI) on the vibrational spectra of amino acids was considered.

Influence of Sm Impurity Atoms on the Switching Effect in Thin Films of GeS

Background and Objectives: Nowadays interest has grown considerably to AivBvi type semiconductor media. Among them there is a special interest to the thin photosensitive films of germanium mono-sulfide. So, GeS thin layers have the ability to contain a large number of lithium ions. Therefore, it is possible to prepare the items: solar cells and super condenser. There are no limitations for practical applications of GeS crystal. Prospects of such semiconductor films are determined by the possibility of holographic recording and effects of switching and memory.

Phase Changes of Multiferroic Magnetic Materials, Used in External Memory Systems

Background and Objectives: A review of studies on technological bases of multiferroic materials for their possible use in devices for the urgent destruction of information is presented. The analysis of characteristics of materials allows one to specify their phase changes caused by external influences and to investigate the magnetic properties.

Electric and Magnetic-Field-Induced Formation of Macrostructures in Ferroelectric Liquid Crystals

Background and Objectives: The study of ferroelectric liquid crystals in smectic C* phase fits together several most relevant research areas, including electro-optic devices with response time in the range of 10 μs. A distinguishing feature of smectic C* liquid crystals is its chiral layered structure, which is formed due to the center of masses orientational ordering along the preferred orientation [called the director].

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.