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A method for the synthesis of mixed-ligand gold glyconanoparticles with average particle size of 20–25 nm at widely variable ratio of the initial glycoligands on the basis of aldoses 6-mercaptohexanoyl hydrazones—condensation products of a series of natural aldoses (N-acetylamino-D-glucose, D-mannose, D-galactose, and L-fucose) with 6-mercaptohexanoic acid hydrazide—has been developed. It has been shown that the obtained gold glyconanoparticles exhibit low toxicity and are active against influenza A/Puerto Rico/8/34 (H1N1) virus at concentrations of 3 and 6 μg/mL.

The condensation products of natural monosaccharides L-fucose, L-rhamnose, N-acetylamino-D-glucose and N-acetylamino-D-mannose with thioglycolic acid hydrazide have a cyclic 1,3,4-thiadiazine structure or are presented in solution in DMSO-d6 by a tautomeric mixture of pyranose and 1,3,4-thiadiazine forms. It was shown that L-rhamnose and N-acetylamino-D-mannose mercaptoacetyl hydrazones exhibit high radioprotective activity, increasing the survival rate of mortally irradiated mice by 35–45%.

A method for the synthesis of gold glyconanoparticles with average particle size of 18–21 nm and low polydispersity index based on readily available thiolated compounds: 3-thiopropionylhydrazones of L-fucose, L-rhamnose, N-acetyl-D-glucosamine, and N-acetyl-D-mannosamine has been developed. It has been shown that some of the gold glyconanoparticles exhibit antitumor activity, and the initial thiolated glycoligands have shown strong radioprotective activity, increasing the survival rate of mortally irradiated mice by 50–70%.

The paper discusses the main stages of development of cryptographic protocols from SSL 2.0 (Secure Socket Layer) to TLS 1.3 (Transport Layer Security), which ensure the protection of transport layer data in the OSI model. A brief description of the modification of the RuTLS protocol based on TLS 1.3 and their main differences is given. The development of IPsec, which provides cryptographic protection of communications at the network level of the OSI model, is considered using examples of the development of the three most commonly used protocols. These include IKE (Internet Key Exchange), AH (Authentication Header), and ESP (Encapsulation Security Payload). For the SSL/TLS and IPsec specifications, the basic handshake protocols and the main stages of their development are considered. The described handshakes include primary cryptographic information exchange cycles in the form of identifiers of interaction participants, one-time numbers, lists of supported cryptographic combinations. Authentication of participants based on certificates, shared symmetric keys, data exchange for establishing a shared Diffie — Hellman secret, development of key material for secret keys of communication sessions, message authentication, and other cryptographic parameters are presented. For different versions of SSL/TLS and IPsec, the logical structures of application data cryptographic protection functions are described.

In experiments in mice, the radioprotective efficacy of sugar-containing compounds was studied based on the condensation products of thioglycolic (TGH) and thiosalicylic (TSH) hydrazides with a series of natural aldoses: the monosaccharides D-glucose (Glс) and D-galactose (Gal) and the disaccharides D‑lactose (Lac) and D-maltose (Mal). It was shown that the use of Glc-TGH and Mal-TSH preparations increases the survival rate of deadly irradiated animals by 25% when administered 1 h before irradiation and by 40% when administered 24 h before irradiation. It is assumed that the leading role in the radioprotective activity of the drugs is played by the protection of the hematopoietic stem cells of the test animals.

The comparative analysis of microheterogeneous structure of the surface of films of amorphous aromatic polyetherimide: poly[4, 4'-bis(4''-N-phenoxy)diphenylsulfon]imide of 1,3-bis(3', 4-dicarboxyphenoxy)benzene (PEI) and poly(imide siloxane) block copolymer (PSI) containing PEI blocks and blocks of dimethylsiloxane units was performed according to electron microscopy. It was shown that anisotropy, long-range order, and the correlation length of density fluctuations increase in PSI film as compared to PEI. PSI samples are characterized by asymmetrical biaxial surface texture, as opposed to PEI, which exhibits axial texture. Periodic density oscillations are observed along the directions of axes of PSI structure at the micron scale. The obtained results evidence microphase separation in PSI film caused by spatially oriented contact interactions between the blocks of dimethylsiloxane units.

A procedure has been developed for the synthesis of gold glyconanoparticles with an average particle size of 15–30 nm and a low polydispersity index on the basis of natural hexose (d-glucose, d-galactose, d-mannose) sulfanylacetyl-, 3-sulfanylpropanoyl-, and 2-sulfanylbenzoylhydrazones and thiolated poly(2-deoxy-2-methacryloylamino-d-glucose).

A procedure has been developed for the synthesis of previously unknown aldose 4-[(ω-sulfanylalkyl) oxy]benzoylhydrazones (where alkyl is hexyl or decyl and aldoses are D-glucose, D-galactose, D-maltose, and D-lactose) that a repromising glycoligands for noble metal nanoparticles. According to the 1H and 13C NMR data, 4-[(ω-sulfanylalkyl)oxy]benzoylhydrazones derived from D-glucose, D-maltose, and D-lactose in crystal and in DMSO-d6 solution have exclusively the cyclic pyranose structure (α- and β-anomers). D-Galactose 4-[(ω-sulfanylalkyl)oxy]benzoylhydrazones in DMSO-d6 solution exist as tautomeric mixtures of cyclic pyranose and open-chain acylhydrazone structures.

This paper describes the development and investigation of compact waveguide electrooptic modulators using original synthesized chromophore-containing polyimides with covalently attached commercial DR-13 dye. Fully polymer planar electro-optic structures with phase-polarization and amplitude modulators in the form of a Mach–Zehnder interferometer were developed and implemented. The characteristics of the developed modulators at a wavelength of 1.3 μm were investigated, and a half-wave voltage of 24 V was achieved with a 1.3 cm length of the active part of the modulator.

A method of synthesis of 3-thiopropinyl derivatives of 5-oxo-1,3,4-benzothiadiazepine-4-acetic acid, potential antihypertensive drugs, vasopeptidase inhibitors, starting from 2-thiobenzoic acid hydrazide has been elaborated.

The article highlights the scientific substantiation of perspective ways of innovative development of national agricultural advisory services in the context of stimulating economic development in rural areas of Ukraine in the conditions of decentralization of power. The study allowed to establish the existing imbalance in the ratio of the main types of agricultural enterprises and agricultural service cooperatives, falling on one advisory service, as well as to determine the causes of significant imbalances in the regional context, the determination of which offers a number of key innovation priorities, activating the integration of education, research, marketing, economic and financial, consulting and other services necessary to provide a complete infrastructure of the economy of rural areas with the potential of basic institutions of NAAS and MES.

The effect of physical factors on the resistance of thin films of nonconjugated polymers was studied. The resistance of polymer films with the metal type of conductivity decreases with an increase in the amount of interchain hydrogen bonds and of metal nanoparticles in the polymer matrix, and also in the presence of a plasticizing additive. Introduction of paramagnetic admixtures and formation of interchain covalent cross-links, on the contrary, increase the resistance of polymer films.

The influence of weight-average-molecular weight (M w ) on the maximal thickness (h ) of the films of polystyrenes (PSs) and poly(methyl methacrylate)s (PMMAs) possessing the level of metal conductivity has been investigated. It has been shown that h is directly proportional to M for both PSs, and PMMAs. This behavior implies the value of h is governed by the size of the random coil of these polymers. These results have been compared with those obtained earlier for other dielectric polymers, and discussed with respect to the influence of the nature of the solvent on the conductive properties of films of dielectric polymers.

The influence of weight-average molecular mass Mw on the maximal width of a conducting layer hmax of polysterene, polymethylmethacrylate, and polyamidine films was investigated. It was shown that hmax increases in proportion to MwS for all investigated polymers. It points to the fact that the hmax value is defined by the macromolecular coil size.

A correlation is found between the proton spin-spin relaxation times in gold nanocomposites based on arabinogalactan in aqueous solutions and the maximum conducting layer thicknesses of films cast from solutions of composites. The obtained correlation is considered from the viewpoint of electrization’s effect on the mobility of macromolecules of the investigated polymer nanocomposites. The dependence of arabinogalactan mobility on the type of solvent (H2O or D2O) is established, and a conclusion is drawn as to the effect of the hydrogen bonds of arabinogalactan with solvent on polymer mobility in solutions.

Successive molecular assembling in polymer chains furnished a series of the comb-shaped copolymers of 4-aminostyrene containing side styrylquinoline chromophore groups. Thermal, thermomechanical, spectroscopic, and luminescent properties of the polymers and low-molecular-weight model chromophores were studied.

Organosilsesquioxane polymers doped with photochromic fulgide dye have been synthesized for use as model reversible holographic photosensitive media, combining high rigidity with the stability of the isomers of the photosensitive dye. The dye diffusion in the polymers, which affords the relaxation of the photo-induced holographic gratings with periods from hundreds to thousands of nanometers, has been studied. The diffusion coefficients have been measured by the method of holographic relaxometry. It is shown that the dye diffusion can be considerably slowed down by heat treatment of the photochromic material.

An increase in the optical transmission in electronic spectra for metal/poly(1,10-decamethylene-acetamidine) systems after UV irradiation is observed, in contrast to polymer and metal films investigated separately where there was no such effect. The increase is explained by changes in the distribution of the electric charge induced by UV irradiation at the metal/polymer interface in a polymer film.

External respiratory function was examined in 79 patients with spinal cord damage at the cervical and thoracic levels before and 1-3, 5-7 days after surgery. They also underwent cliniconeurological and neurophysiological studies. Two groups were identified. These included: 1) patients with spinal cord damage at the C1-5 level and 2) those with this condition at the C6-Th8 level. According to spinal cord conduction disturbance, the groups were divided into two subgroups: a and b. External respiration was investigated after removing a respirator from the patient. Prior to surgery, subgroup 1a had respiratory disorders by the mixed type; subgroups 1b, 2a, and 2b had restrictive respiratory disorders. Postoperatively, all the patients had mixed neurogenic external respiratory disorders that were more significant in subgroups 1a and 2a. In the postoperative period, respiratory disorders became worse and were of mixed nature, which was associated with deteriorated spinal cord function at surgery. Subsequently, there was their regression by day 7. Patients with significant respiratory disorders must be managed in an intensive care unit.

The authors analyze mortality rates during 338,000 anesthetic procedures. Mortality was 0.02%. Epidural, spinal, and plexus anesthesias were 15% of the total number of anesthetic procedures. In this group, mortality was twice less [0.01% (6 patients)] than that under general anesthesia. Under regional anesthesia, all deaths were associated with the induction of epidural anesthesia. A human factor is of profound importance for fatal cases under regional anesthesia. Regional anesthetic techniques are safer than general anesthetic ones.

The authors elaborated an algorithm of respiratory management (RM) based on the correlation of RM parameters with the actual and proper thoracopulmonary compliance (C). The algorithm was tested on 42 patients with affections of the central nervous system (CNS) due to severe craniocerebral trauma, spinal trauma, cerebral stroke and multitrauma. Thirty-nine case-matching patients where in the control group--the routine RM algorithm was used for them. Mean pressure in the respiratory paths (Pmean, C, PaO2/FiO2 and rSO2 readings by the Glasgow coma scale, cerebral perfusion pressure, and consumption of sedatives, muscle relaxants and vasopressins as well as frequency rate of acute pulmonary lesions (APL) were registered. The RM algorithm provided for a more effective prevention and treatment of APL versus the routine RM--it cut, 3-fold, the remote APL. With the above RM algorithm, the need in sedatives, muscle relaxants and vasopressins went down from day 2. Positive trends in the neurological status as well as normalized rSO2 were observed earlier versus the controls. Finally, its use ensured a more favorable treatment outcome.

The clinical, immunobiochemical and hemostasiological parameters of the systemic inflammatory response (SIR) were studied in 51 patients with diffusive peritonitis. The study showed that lactoferrin, plasminogen/plasmin and alpha 2-macroglobulin can be used, in a set, as informative indices of SIR. A reduced content of lactoferrin, a smaller concentration of proteases inhibitor alpha 2-macroglobulin and a higher relation between plasminogen and plasmin correlate with an unfavorable outcome of the disease beginning from the 1st postoperative day. An activity of Willebrandt's factor is a diagnostic and prognostic marker, which determines a lesion to the endothelium system.

Sixty-one patients with severe craniocerebral injuries were examined on days 1-3 after the injury. Consciousness was no more than 8 points by the Glasgow Coma Scale. The patients were divided into 2 groups: 1) favorable outcomes and 2) unfavorable outcomes. Gaseous composition of arterial and venous blood was analyzed in all patients, intracranial pressure (ICP) and cerebral perfusion pressure (CPP) were measured, artificial ventilation of the lungs (AVL) and noninvasive monitoring of cerebral oxygenation (CO) were carried out. The results indicate that continuous monitoring of CPP and CO helps control the time course of cerebral blood flow, thus promoting early detection and effective treatment of cerebral ischemia in critical patients.

To study blood-brain barrier permeability and proteolytic changes in in patients with severe brain injury and to evaluate their impact on its course and outcome, the concentrations of albumin, plasminogen (plasmin), alpha 2-macroglobulin, alpha 2-antiplasmin, and alpha 1-antitrypsin were examined in 58 victims by enzyme immunoassay. The control group comprised 20 patients examined for lumbar discal hernia. The studies indicate that early severe brain injury showed blood-brain barrier dysfunction whose severity can be detected by the spinal fluid levels of albumin, plasminogen, and alpha 2-macroglobulin. Proteolytic changes in spinal fluid are determined by its albumin, plasminogen (plasmin), alpha 2-macroglobulin, alpha 2-antiplasmin, and alpha 1-antitrypsin concentrations and affect the development of secondary brain lesion and they are of practical value.

The CSF levels of albumin, alpha 2-microglobulin and IgG were studied in patients with severe brain injury. Elevated CSF levels of albumin and alpha 2-microglobulin were found in more severe patients. The level of IgG level was within the normal range. Endogenic protease-bound alpha 2-microglobulin may cause secondary cerebral tissue lesion, by closing the vicious circle.

Objective: to evaluate the states of microcirculation, cerebral perfusion intracranial pressures in patients with isolated severe brain injury (SBI) and to determine their possible relationships. Subjects and methods. 148 studies were performed in 16 victims with SBI. According to the outcome of brain traumatic disease, the patients were divided into two groups: 1) those who had a good outcome (n=8) and 2) those who had a fatal outcome (n=8). Microcirculation was examined by skin laser Doppler flowmetry using a LAKK-01 capillary blood flow laser analyzer (LAZMA Research-and-Production Association, Russian Federation). All the victims underwent surgical interventions to remove epi-, subdural, and intracerebral hematomas. A Codman subdural/intraparenchymatous intracranial pressure (ICD) sensor (Johnson & Johnson, United Kingdom) was intraoperatively inserted in the victims. Cerebral perfusion pressure (CPP) was calculated using the generally accepted formula: CPP = MBP (mean blood pressure) — ICD. ICD, CPP, and microcirculation were studied on postoperative days 1, 3, 5, and 7. Their values were recorded simultaneously. Ninety and 58 studies were conducted in the group of patients with good and fatal outcomes, respectively. Results. No correlation between the changes in MBP, ICD, and microcirculatory parameters suggested that the value of ICD was determined by the nature of brain damage and it was the leading and determining indicator in the diagnosis and treatment of secondary cerebral lesions. The amplitude of low-frequency fluctuations directly correlated with ICD, which indicated that they might be used to evaluate cerebral perfusion and impaired cerebral circulation indirectly in victims with severe brain injury. Conclusion. The laser Doppler flowmetric technique makes it possible not only to qualitatively, but also quantitatively determine changes in the tissue blood flow system in severe brain injury. With this technique, both the local and central mechanisms which are responsible for changes in tissue blood flow autoregulation suffer, with a preponderance of the latter mechanisms. Key words: microcirculation, intracranial pressure, cerebral perfusion pressure, severe brain injury.

Objective: to define the types and specific features of hemodynamic responses in miners with a service length of 10 years or more in the early posttraumatic period after severe mechanical injury. Subjects and methods. Noninvasive central hemody-namic studies using tetrapolar rheography were conducted in 55 injured miners with an underground service length of 10 years or more (a study group) and in 54 victims without underground service (a control group). Major hemodynamic parameters, such as mean blood pressure, heart rate, cardiac index, stroke index, vascular resistance index, were measured over time: on admission and on days 3, 5, and 7. The victims with severe concomitant injury were matched by age and the nature and severity of mechanical injuries. Results. The study has shown that in the early posttraumatic period from days 3 to 7, the miners with an underground service length of 10 years or more had hypodynamic, hyperdynamic, and normodynamic circulations in 37.2, 50.5, and 12.3%, respectively. Unlike the miners, the controls exhibited in this period a hyperdynamic type in 96.0% and only 4.0% were found to have a hypodynamic type. Conclusion. The miners and the victims without underground service were observed to have the similar hemodynamic responses to severe mechanical injuries within the first 24 hours posttraumatically. Beginning with the 3rd-to-7th day, the ratio of hemodynamic circulatory types changed in the miners, by increasing hypodynamic responses. This may be accounted for by the diminished reserve capacities of the circulatory system due to long-term exposure to poor industrial factors.

This study was undertaken to determine the general regularities of hemodynamic disorders in relation to the severity of brain damage for the subsequent development of pathogenetically warranted methods for their correction in the complex of intensive care for severe brain injury. Studies were made in 67 victims, by using neurophysiological studies (electroencephalography, studies of acoustical stem-evoked potentials and somatosensory stem-evoked potentials), computed tomography and magnetic resonance imaging. Central hemodynamics was studied by a Sirecust 1260 monitoring system using Swan-Ganz catheters and thermodilution. The overall condition of the victims was regarded as very bad. Loss of consciousness was 8-4 scores by the Glasgow coma scale. The studies have indicated that the victims in whose clinical picture the signs of compression of the cerebral hemispheres dominate over those of the latter’s contusion develop a hemodynamic reaction by the normodynamic type. The hyperdynamic type of hemodynamic disorder develops in cerebral hemispheric and diencephalic lesions with a parallel increase in oxygen transport and uptake; and in severe brain injury, lower brain stem damages are accompanied by hemodynamic disorder by the hypodynamic type with a reduction in oxygen transport and uptake.