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Manufacturers of agricultural machines, when designing, pay a little attention to its impact on soil, thus producing models with high compression loads on the soil or with a small contact area between the tyres/tracks and the soil surface. Therefore, the aim of this study is to evaluate the negative impact of both wheeled and tracked agricultural tractors on the soil, in terms of soil compaction, and its causes (i. e. design features of tractor tyres/tracks), during the last six decades (i. e. from 1961 to 2021). Soil compaction is caused by the pressure applied by agricultural machines on the soil through the contact area of their tyres/tracks with the soil surface. So, the main indicator of the negative impact on the soil by the tractors manufactured during the last 60 years, i. e. the average pressure applied by the tyres or tracks of tractors manufactured in EU and in the post-Soviet cuntries from 1961 to 2021 to the soil, was computed. A general decrease of the average pressure of the tyres/tracks on the soil can be observed in 1980s and 1990s, followed by its general increase since 2000, above all for the tractors having power higher than 140 kW. Thus, there is an urgent need to assess spatial and temporal changes in soil vulnerability to compaction, that depends on weather conditions and soil properties, as well as agricultural management practices, and can only be fully assessed by means of a combination of traditional techniques (i. e. use of soil cone penetrometer followed by 2D mapping using GIS or 3D mapping through geostatistics) and mechanical approaches (i. e. computation of agricultural machine parameters – soil contact area). The results show that tractor manufacturers did not take care of reducing soil compaction during the considered period.

Introduction. Degenerative retinal diseases, including glaucoma, are the main cause of vision loss in the adult population. The development and improvement of drug treatment of this group of diseases is an urgent problem.Aim. Study of a new dosage form of methylethylpyridinol in the form of an ophthalmic gel.Materials and methods. The objects of the study were samples of eye gels containing methylethylpyridinol, for which mucoadhesion was studied by a combination of in vitro / ex vivo methods. Biodegradation and release kinetics of the active substance from the dosage form were studied using a dissolution tester in an artificial tear fluid medium. The shelf life of the dosage form was established in accordance with the stability study program. Determination of the local irritative action was carried out by conjunctival test in 10 rabbits of chinchilla breed weighing 3,6–4,1 kg.Results and discussion. The article presents the results of the study of biopharmaceutical characteristics of the previously developed ophthalmic gel of methylpyridinol based on a nonionic polymer – hydroxyethylcellulose brand Natrosol™ 250 HHX. A comparative study of mucoadhesion by in vitro / ex vivo flow of ophthalmic gel samples in the range of hydroxyethylcellulose concentration in the gel of 1–1.5 % was performed. The sample with 1.5 % polymer content had the best adhesive characteristics because it had a minimum flow rate: in vitro 2.7 · 106 m/s and ex vivo 2.3 · 106 m/s. Dissolution kinetics and visual biodegradation of the sample after "Dissolution" test were studied, which indicates prolonged release of methyl ethyl pyridinol from the gel. The stability of the developed dosage form under long-term and stress conditions was shown. The local irritating effect was estimated by the conjunctival test.Conclusion. The main biopharmaceutical characteristics of the developed ophthalmic gel methylpyridinol were determined and it was shown that it can be used as a delivery system for the treatment of degenerative retinal diseases because it possesses marked bioadhesive properties and prolonged release. The shelf life of the dosage form was determined, which was 2 years. Stress studies of methylethylpyridinol gel were carried out. The developed ophthalmic gel has no local irritating effect.

The relevance. Associated with the problem of increase in efficiency of algorithms for monitoring and controlling the dynamic operation modes of wells equipped with an electric submersible pump with adjustable supply. The result summarizes and develops the previously published solution on the design of a dynamic well model, through the transition from linearized correlations to quadratic relationships between states at key points of a lift. These points properly reflect the observed forms of behavior in transient and equilibrium operating modes at full start-stop control ranges. The main aim. Updated description of a comprehensive quadratic barometric model of the «reservoir–lift–electric pump–well head» type well, focused on the tasks of automatic control and regulation in real time. Objects. Well with frequency-regulated submersible pump. Methods. Material balance, percolation, hydrostatics, quadratic kinetics of friction losses, numerical modeling of differential equations, finite-dimensional description of the complex hydrodynamics of the well, taking into account the potential and kinetic head losses in the lift. Results: (1) Updated mathematical description of the hydrodynamics of the well with an electric submersible pump creates the basis for: • more reliable solution of inverse problems of parametric model support according to the data of field control, • refined assessment of the adjustment potential, predicting the dynamics of a possible system output beyond the boundaries of functional stability, • technologies of numerical and analytical design of optimal solutions when selecting the parameters of arrangement and laws of operational regulation, • synthesis of dynamic observers of an extended state vector synchronously operating with the dynamics of controlling well-head and deep pressure. (2) The results of the computational analysis demonstrate a complex behavior that does not match the graph of the inflow and pump supply, when changing the frequency and wellhead pressure. This explains the observed effect of the multi-tempoity of transient processes during starts and stops and possible instability of the supply with a sharp decrease in frequency. (3) Estimates of discrepancy between the solutions for a quadratic model and a linearized prototype indicate an increase in errors of linearized analysis with strong deviations of operating modes from the equilibrium-calculated states. The refinements in dynamically disturbed operating modes delivered by the updated model are important for improving the reliability of operational control systems and parametric estimation for data control mode states.

K+Λ(1405) photoproduction has been studied at the BGOOD experiment via the all neutral decay, Λ(1405)→Σ0π0. The unique BGOOD experimental setup allows both the cross section and Λ(1405) invariant mass distribution (line shape) to be measured over a broad K+ polar angle range, extending to extreme forward K+ angles unattainable at previous experiments.Evidence is provided for the role of a triangle singularity driven by the N⁎(2030) resonance, which appears to contribute significantly to K+Λ(1405) photoproduction. This is observed in the integrated cross section which was determined with unprecedented energy resolution and supported by the angular distributions. The measured line shape is also in agreement with the previous results of CLAS and ANKE, and is consistent with two poles derived in χPT based models.

The coherent reaction, γd→π0π0d was studied with the BGOOD experiment at ELSA from threshold to a centre-of-mass energy of 2850MeV. A full kinematic reconstruction was made, with final state deuterons identified in the forward spectrometer and π0 decays in the central BGO Rugby Ball. The strength of the differential cross section exceeds what can be described by models of coherent photoproduction and instead supports the three isoscalar dibaryon candidates reported by the ELPH collaboration at 2.38, 2.47 and 2.63GeV/c2. A low mass enhancement in the π0π0 invariant mass is also observed at the d⁎(2380) centre-of-mass energy which is consistent with the ABC effect. At higher centre-of-mass energies, a narrow peak in the π0d invariant mass at 2114MeV/c2 with a width of 20MeV/c2 supports a sequential two-dibaryon decay mechanism.

A method of testing of threshold SiO2 aerogel Cherenkov detectors using cosmic radiation is described. The method requires a minimum amount of additional electronics and does not involve massive absorber layers (e.g., lead). The method makes it possible to directly take into account the threshold in determining the efficiency of the detectors under study and to test their operation in different energy ranges for relativistic charged particles. Good agreement between the results of the simulation and measurements was obtained. [ABSTRACT FROM AUTHOR]

To study the E1 giant resonance in atomic nuclei, it is important to study the energy and emission angle distributions of fast neutrons from (γ, n)-reactions. The paper considers some features of such studies on beams of γ-quanta produced by inverse Compton scattering with small spreads of their energy, angles, transverse dimensions, duration, and polarization in these beams. It is proposed to use fast neutron spectrometers using both amplitude and time-of-flight data. [ABSTRACT FROM AUTHOR]

Introduction. Effective delivery of ophthalmic drugs is challenging. The eye has a number of protective systems and physiological barriers, which is why ophthalmic dosage forms have a low bioavailability, usually not exceeding 5 %. Topical drug administration is relatively easy to use and is most commonly prescribed by physicians for the treatment of ophthalmic diseases, especially the anterior segment of the eye. However, when using traditional delivery systems, a number of problems arise: patients' violation of the drug administration technique, and, as a consequence, a decrease in treatment compliance, restriction of drug delivery to the target eye tissues due to low epithelial permeability and rapid clearance after drug administration. Maintaining a constant therapeutic drug level is another challenge that traditional delivery systems often fail to cope with.Text. The article discusses the types of ophthalmic delivery systems. Traditional ones are represented by such dosage forms as eye drops, ointments, gels. Modern ophthalmic dosage forms are represented by: eye films, contact lenses and eye implants. The characteristics, advantages and disadvantages of each type of delivery systems and their promising directions of development, as well as modern developments in this area are given.Conclusion. Currently, most of the scientific research on the development of ophthalmic delivery systems is devoted to obtaining dosage forms capable of maintaining a constant concentration of the drug in the target tissue, providing the transport of active ingredients to them. This is achieved by using modern advances in nanotechnology and polymer chemistry. Receive liquid and soft dosage forms with micro-, nano- and micro-nano-carriers. Polymeric delivery systems such as films, lenses and implants are being actively developed and studied. The development of modern technological approaches opens up new possibilities for the treatment of a wide range of ophthalmic diseases by reducing the side effects often induced by the intrinsic toxicity of molecules, reducing the frequency of the administered dose and maintaining the pharmacological profile of the drug. Thus, the use of modern ophthalmic delivery systems can significantly limit the use of invasive treatments.

The γp→K+Σ0 differential cross section at extremely forward angles was measured at the BGOOD experiment. A three-quarter drop in strength over a narrow range in energy and a strong dependence on the polar angle of the K+ in the centre-of-mass of the reaction is observed at a centre-of-mass energy of 1900 MeV. Residing close to multiple open and hidden strangeness thresholds, the structure appears consistent with meson-baryon threshold effects which may contribute to the reaction mechanism.

The article describes the main requirements for ophthalmic gels and presents the study of the rheological properties of ophthalmic gels, registered in the Russian Federation: Korneregel®, Solcoseryl®, Vidisic®, Ophtagel®, Oftan-Timogel®, Systein gel®. The parameters of rheological measurements conducted for ophthalmic gels are substantiated. On the basis of the results obtained, optimum rheological characteristics are suggested, which can be recommended for use in the development of ophthalmic gels.

Studies of the osmotic activity of emoxypine and dalargine ophthalmic experimental gels samples based on various polymers and also studies of some marketed in Russia ophthalmic gels are presented in the article. Selection of the most promising for further study emoxypine and dalargine experimental gel compositions was based on the comparative study of Vidisic®, Solcoseryl®, Corneregel®, Oftagel® ophthalmic gels as well as 0,9% sodium chloride solution used as the standard of osmolality. Optimal values of osmotic activity have an experimental sample of an emoxypine ophthalmic gel containing Natrosol™ 250HHX at a concentration of 1%, as well as Oftagel® and Solcoseryl® gels.