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Objective. The article proposes design solutions aimed at the comprehensive modernization of the cold supply system of the ice palace "Puck" in Sochi, to reduce its impact on the environment.Method. A water reuse system has been created and a technology has been developed for using low-temperature heat that is released during the operation of the refrigeration machine.Result. A refrigeration plant has been developed that allows you to utilize, accumulate and direct the heat of condensation for the secondary use of thermal energy by other engineering systems at the facility, thereby reducing heat and greenhouse gas emissions into the Earth's atmosphere and increasing the technological capabilities of cooling.Conclusion. The proposed methods make it possible to make the necessary calculations and select equipment for the implementation of the developed systems in ice arenas.

carried out with specified periodic actions, we can distinguish their multiplicity, diversity and originality. However, with regard to the sterilization processes in autoclaves, there is currently no high-quality control system for them, which still determines the relevance of this task. The article offers a selection of criteria that can be applied to the automatic control system, taking into account the specifics of the processes that occur during the sterilization of canned food using an autoclave. This article also discusses the structure of this process using the basics of the theory of automatic control. In addition, it provides a simulation of these processes. In contrast to the existing structures, the proposed automatic control structure is characterized by openness, which increases the design efficiency in the development of such control systems. The basis of this approach in the form of a two-circuit four-channel controller, allows you to improve existing and create new automatic control systems for sterilization plants.

ZnO/Fe2O3 nanocomposites with different concentration and thickness of the Fe2O3 layer were obtained by two-stage aerosol vapor deposition (AACVD). It was shown that the ZnO particles have a wurtzite structure with an average size of 51–66 nm, and the iron oxide particles on the ZnO surface have a hematite structure and an average size of 23–28 nm. According to EDX data, the iron content in the films was found to be 1.3–5.8 at.%. The optical properties of the obtained films were studied, and the optical band gap was found to be 3.16–3.26 eV. Gas-sensitive properties at 150–300 °C were studied using a wide group of analyte gases: CO, NH3, H2, CH4, C6H6, ethanol, acetone, and NO2. A high response to 100 ppm acetone and ethanol at 225–300 °C and a high and selective response to 300–2000 ppb NO2 at 175 °C were established. The effect of humidity on the magnitude and shape of the signal obtained upon NO2 detection was studied.

The article proposes an automatic control system that meets the technical criteria of the technological process of sterilization of canned food in an industrial autoclave. The proposed algorithm of operation and the developed structure of the automatic process control system implement modern automatic control laws and take into account the mutual influence of control coordinates. A two-circuit four-channel temperature and pressure regulator in the autoclave has been developed, which reduces the volume of defective products and saves energy resources, due to a more accurate correction of the mutual influence of control circuits. The regulator is the basis for creating an automatic control system that allows compensating for disturbing effects associated with changes in technological parameters. The proposed control device can be used to improve existing and create new automatic control systems for sterilization installations. The reliability of the study was proved by means of simulation modeling and comparison of the results with experiments on the operating equipment of the cannery.

We studied the effects of cooling to -10°C and re-warming to 37°C on slices of rat olfactory cortex. The amplitudes of action potential in the lateral olfactory tract and excitatory postsynaptic potential activated by AMPA recovered during slow cooling/re-warming (0.1°C/min), while during rapid cooling/re-warming (9°C/min), they surpassed the control values. NMDA receptor-dependent mechanism was blocked in both cooling/re-warming modes. Swelling of the brain slices was observed during re-warming, especially during rapid cooling/re-warming. Nerve fibers of the lateral olfactory tract and AMPA-related processes survived deep cooling/re-warming, while NMDA-related processes were irreversibly blocked.

The aim of the present study was to explore the neuroprotective effects of the mystixin-7 mini-peptide (MTX, a synthetic corticotropin-releasing-factor-like, 7-amino-acid peptide) on an in vitro oxygen glucose deprivation model (OGD, 10min). The study used a technique of on-line monitoring of changes in α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic receptor (AMPAR) and N-methyl-d-aspartic acid receptor (NMDAR)-mediated field excitatory postsynaptic potentials (fEPSPs) in the olfactory cortex slices in the OGD model. OGD resulted in an irreversible blockade of both AMPAR and NMDAR activity. Pretreatment of slices by MTX and their subsequent exposure to OGD resulted in decreased activity of these postsynaptic mechanisms (AMPARs, 71%; NMDARs, 68% as compared to baseline), but they were not blocked altogether. The degree protection of activity of both AMPARs and NMDARs had dose-dependent manner, with a maximal effect at 100mg/mL. These protective effects were retained after the removal of MTX from the bathing medium. To evaluate the protective efficacy of MTX on NMDARs, the slices were pretreated by MTX and exposed to OGD and then treated with l-glutamate (1mM). NMDARs' response to application of l-glutamate was minimal at higher concentrations of MTX and maximal at lower concentrations. These findings indicate that the molecules of MTX interact with a certain amount of NMDARs, and thereby protect them from the OGD. Pretreatment of slices with MTX contributed to the protection of network activity against OGD and promoted the development of the learning process in the form of long-term potentiation. To specify the protective effects of MTX, it was denatured by trypsin. The proteolytic cleavage of MTX resulted to a significant decrease in the activity of both AMPARs and NMDARs against OGD as compared with that of the native peptide. Together, these findings provide further insight into the protective potential of the MTX mini-peptide. We believe that the data presented can be the basis for the development of therapeutics MTX-based medications for the treatment of the ischemic stroke.

Experiments were performed on male Wistar rats. The specimens with an active strategy of behavior were exposed to unavoidable water-immersion stress. Surviving slices of the olfactory cortex were obtained 10 days after stress. The neurohormone had a strong inhibitory effect in 40% slices from active rats. The activity of glutamate receptors decreased, while the function of GABA receptors increased in 60% slices. Our results indicate that the depressive state of behaviorally active animals due to exposure to unavoidable stress is not necessarily mediated by the corticoliberinergic mechanisms in cortical structures.

Proteoglycans synthesized by rat myoblasts L6J1 in culture were isolated using sorbent Q-Sepharose from culture medium, extracellular matrix (ECM), and cells. Elution of the sorbed material in a NaCl gradient separated proteoglycans from the bulk of proteins eluted at low concentration of the salt. Four fractions (fractions I-IV) were obtained for each component of the cell culture, including two proteoglycan fractions for the ECM and culture medium and one fraction for the myoblasts. Proteoglycans of the culture medium were virtually completely represented by proteoglycans of fetal calf serum. With enzymes chondroitinase ABC and heparinase III chondroitin/dermatan sulfate proteoglycans were shown to prevail in all components of the myoblast culture. The core proteins of proteoglycans were characterized by electrophoresis.

The reactions of β-naphthol with 5-diazoimidazoles and imidazolyl-5-diazonium salts containing chemically different carboxamide groups in position 4 were studied. Heterocyclization of 4-arylcarbamoyl-5-(2-hydroxynaphthylazo)imidazoles formed in these reactions was investigated. The presence of the NH fragment in the amide group prevents this process, the reaction giving instead 3-substituted 3,7-dihydroimidazo[4,5-d][1,2,3]triazin-4-ones, which is due to reversibility of C-azo coupling. Methods for modification of 1-ethoxycarbonyl group in the naphtho[2,1-e]imidazo[5,1-c][1,2,4]triazine system were developed and used to prepare substituted carboxamides inaccessible by other routes.

Preincubation of cultured slices of the olfactory cortex of rat brain with heat shock protein in a concentration of 1 microg/ml protected the pre- and postsynaptic mechanisms of glutamatergic synaptic transmission from glutamate excitotoxicity (50 mM) inducing blockade of excitatory postsynaptic function and reducing presynaptic processes. It was hypothesized that heat shock protein protects AMPA and NMDA receptor-mediated processes.

The novel three-component reaction of isoquinoline with isothiocyanates and isocyanides leads to a variety of new imidazoisoquinolines. The zwitterionic ground state of these new ring systems is established by means of NMR and X-ray analysis. Use of phthalazine instead of isoquinoline gives access to imidazole annulated phthalazines.

Successive alkylation of 5-(3-phenylthioureido)-3H-imidazole-4-carboxamides with alkyl halides and chloroacetone gave (N-oxopropylimidazolyl)isothioureas, which were easily converted into derivatives of purine and imidazopyrazinone. In the case of ethyl 5-(3-phenylthioureido)-3H-imidazole-4-carboxylate, primary alkylation occurs at the N atom of the imidazole ring. Reactions of 5-(3-phenylthioureido)-3H-imidazole-4-carboxamides with haloketones afforded a number of 4-hydroxy-2-imidazolyliminothiazolidines and 2-imidazolylimino-Δ4-thiazolines.

A reaction between levulinic acid, isocyanides and primary amines has been examined in distilled water and in surfactants solutions. It is demonstrated that the reaction gives good results at the different concentrations including one well above the solubility limit. A simple and eco-friendly protocol for libraries production is described.

Changes in bioelectrical activity of nerve cells after their long-term exposure to autoblood were studied in vitro on cultured brain slices. This model simulated the events characteristic of a hemorrhagic stroke. Brain slice was placed into a glass vial with autoblood for 60-420 min, after which the slice was transferred into a perfusion chamber and after washing from autoblood their focal potentials were recorded. The level and reversibility of disorders in nerve cell activity were detected by comparing the parameters of focal potentials with the control values. Delayed effects of autoblood were detected, manifesting in the progress in disorders of nerve cell activity with prolongation of exposure in the blood, and the period after which they could be restored was determined.

Incubation of cultured slices of the olfactory cortex from rat brain with L-carnosine in concentrations of 50, 250, and 500 M induced activation of glutamatergic and GABAB-ergic mechanisms and facilitated long-term posttetanic potentiation. The effect of L-carnosine is mediated by its effect on AMPA- and NMDA-related glutamatergic receptors and on inhibitory GABAB receptors.

A new approach to the design of multicomponent reactions is introduced. As a result the novel reaction of gem-diactivated olefins with 4-nitrophenol and isocyanides leading to substituted propionamides or succinimides was discovered.

Cycloaddition reactions of 5-diazopyrazoles and 5-diazoimidazoles with acyl isothiocyanates give thiatriazine derivatives.

The cycloaddition of diazoazoles with acylisothiocyanates has been found to result in the formation of a 1,2,3,5-thiatriazine ring. This new reaction was used to prepare novel 8-substituted 4-[benzoylimino-4H-imidazo(pyrazolo)][5,1-d] -[1,2,3,5]thiatriazines. The structures of the compounds prepared were carefully studied by X-ray diffraction, IR and NMR spectroscopy.

We studied the ability of heparin to modify synaptic activity on the original stroke model in vitro. Cultured slices of the brain slices from hypertensive rats were treated with the auto blood clot. Administration of heparin (2 mg/ml) before autoblood treatment had a protective effect on ionotropic glutamatergic and GABAergic receptors, whose activity was inhibited by the blood.

Reaction of title compounds (I) with various phenacyl bromides leads to S-alkylation products (III) as a mixture of E/Z-isomers.

Heating of imidazolyl- and phenylazo-naphthols in acetic acid in the presence of p-toluenesulfonic acid and dimethylaniline yields imidazolyl- and phenyl-(p-dimethylamino)azobenzenes, which suggests the intermediacy of the corresponding diazo compounds.

Reaction of 5-diazo-4-nitroimidazole with concentrated hydrochloric acid leads to 4-chloro-5-diazoimidazole. The same product is formed together with a small quantity of 5-chloro-4-nitroimidazole with 1 N hydrochloric acid, but with 0.1 N hydrochloric acid only chloronitroimidazole was isolated. The results obtained are explained with the aid of quantum chemical calculations.

The first example of the ring transformation of 1,2,3-thiadiazoles involving four atoms of the side chain to form 5H-[1,2,3]triazolo-[5,1-b][1,3,4]thiadiazines is presented.

Azo compounds obtained by the coupling of 5-diazoimidazoles with diethyl esters of nitro-, chloro-, bromo-, and acetylaminomalonic acids under conditions of base catalysis are cyclized to give 1,4-dihydroimidazo[5,1-c]-1,2,4-triazin-4-ones or imidazo[5,1-c]-1,2,4-triazoles. The chloro, bromo, and nitro groups in the bicyclic products are readily replaced by action of nucleophiles. The imidazotriazinones are converted to chloroimidazotriazines by reaction with thionyl chloride or phosphorus oxychloride

Novel 2-pyrazolinylthiazoles 1 are prepared by reaction of 2-hydrazinothiazoles 2 with 1,3-dicarbonyl compounds of type 3. The conditions of the aromatization of 1 to 2-(3-aryl-5-trifluoromethylpyr...

A new method was proposed for the synthesis of indoles containing the isocyanide group by the reaction between aromatic isocyanides and trialkylamines.

A number of 2- and 5-triazenoimidazoles were prepared by the coupling of diazo compounds with aliphatic amines; however, 4,5-dicyanoimidazole-2-diazonium chloride was transformed into 2-amino-1-methylimidazole-4,5-dicarbonitrile.