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In this study, we observed magnetohydrodynamic (MHD) activity of the spherical tokamak Globus-M2 which led to a deterioration in plasma confinement, such as a transition from the H-mode to L-mode, or even disruption. This instability was found to be tearing modes, which are a result of the formation of magnetic islands in plasma and which impose limits on plasma pressure. The width and velocity of the islands are key parameters that determine their impact on plasma confinement. The Doppler backscattering (DBS) method has been shown to be effective for the study of MHD activity. This method was employed on the spherical tokamak Globus-M2, together with an array of magnetic probes, to study the tearing modes. The available DBS systems allowed for simultaneous measurements from half of the minor radius to the separatrix. The results are presented of our investigation of tearing modes that lead to a transition from the H-mode or a disruption. Comparative analysis was conducted of the observed tearing modes and the influence of different plasma parameters on their development.

This paper presents the first results of a study of the LH transition on the new spherical Globus-M2 tokamak using the Doppler backscattering (DBS) diagnostic. New data characterizing the H-mode of discharges with higher values of the plasma parameters, such as magnetic field Bt up to 0.9 T and plasma current Ip up to 450 kA, were collected and analyzed. An upgraded neutral beam injection (NBI) system was used to initiate the LH transition. DBS allows the measurement of the poloidal rotation velocity and the turbulence amplitude of the plasma. The multi-frequency DBS system installed on Globus-M2 can simultaneously collect data in different areas spanning from the separatrix to the plasma core. This allowed for the radial profiles of the rotation velocity and electric field to be calculated before and after the LH transition. In addition, the values and temporal evolution of the velocity shear were obtained. The associated turbulence suppression after the transition to the H-mode was investigated using DBS.

Filaments or blobs are well known to strongly contribute to particle and energy losses both in L- and H-mode, making them an important plasma characteristic to investigate. They are plasma structures narrowly localized across a magnetic field and stretched along magnetic field lines. In toroidal devices, their development is observed to take place in the peripheral plasma. Filament characteristics have been studied extensively over the years using various diagnostic techniques. One such diagnostic is the Doppler backscattering (DBS) method employed at the spherical tokamak Globus-M/M2. It has been observed that the DBS signal reacts to the backscattering from filaments. However, the DBS data have proven difficult to analyze, which is why modelling was undertaken using the code IPF-FD3D to understand what kind of information can be extrapolated from the signals. A circular filament was thoroughly investigated in slab geometry with a variety of characteristics studied. Apart from that, the motion of the filaments in the poloidal and radial directions was analyzed. Additionally, other shapes of filaments were presented in this work. Modelling for the real geometry of the Globus-M/M2 tokamak was performed.

In most present-day tokamaks, the majority of the heating power comes from sources such as neutral-beam injection (NBI) and other types of auxiliary heating which allow for the transfer of energy to the plasma by a small population of externally introduced fast particles. The behavior of the fast ions is important for the overall plasma dynamics, and understanding their influence is vital for the success of any future magnetic confinement devices. In the TUMAN-3M tokamak, it has been noted that the loss of fast particles during NBI can lead to dramatic changes in the rotation velocity profiles, as they are responsible for the negative radial electric field on the periphery.

Cranberries are a rich source of bioactive compounds that comprise a healthy diet. Cranberry is abundant in nutritional components and many bioactive compounds that have antioxidant properties. Both American (Vaccinium macrocarpon) and European (Vaccinium oxycoccus) cranberry species are rich in polyphenols such as phenolic acids, anthocyanins and flavonoids, and is one of the few fruits that is high in proanthocyanidins, which is linked to many health benefits. The review systematizes information on the chemical composition of cranberry, its antioxidant effect, and the beneficial impact on human health and disease prevention after cranberry consumption, and in particular, its effect against urinary tract inflammation with both adults and children, cardiovascular, oncology diseases, type 2 diabetes, metabolic syndrome, obesity, tooth decay and periodontitis, Helicobacter pylori bacteria in the stomach and other diseases. Additional research needs to study cranberry proteomics profiling, polyphenols interaction and synergism with other biologically active compounds from natural ingredients and what is important in formulation of new functional foods and supplements.

The paper presents the results of analysis of entrepreneurial curricula delivered at Russian universities. The analysis yielded the following results. Te proportion of credits aimed at developing hard skills significantly outweighs the proportion of soft skill-focused credits. The share of credits for forming hard and soft skills at both undergraduate and graduate levels is roughly the same. There are large differences between state and private universities as regards the proportion of credits aimed at forming hard skills: this proportion is higher at state universities than private ones. The analysis also confirmed a significant difference in the proportion of credits for hard skills disciplines for generalist entrepreneurial curricula and specialist programmes: it is higher in general curricula and lower in specialized ones. At the same time, these curricula are not noticeably different as regards the proportion of credits focused on forming soft skills. Our research showed that Russian universities have a low potential for influencing and supporting innovative entrepreneurship through their activities. One of the major persisting challenges for Russian universities as regards entrepreneurial education is the delivery of learning outcomes sought after on the market. Another problem is linked to a critically low share of courses aimed at developing soft skills in curricula for future entrepreneurs. We found that the presence of a rather high proportion of private education providers in the Russian higher education system has not prompted the development of entrepreneurial curricula. Their role in producing an active economic class of entrepreneurs and fostering self-employment is clearly insufficient.

Doppler backscattering (DBS) is a microwave diagnostics method typically used to study the plasma rotation velocity. Apart from conventional techniques, more advanced forms of DBS implementation were suggested on Globus-M. More specifically the study of a variety of oscillating processes was performed using DBS. In this review we present a detailed description of all of the methods and techniques employed in Globus-M alongside results obtained using DBS in all the years up until the shutdown of the tokamak. These include research similar to that done on other devices into the properties of such phenomena like geodesic acoustic modes or limit cycle oscillations, along with innovative works regarding the detection and investigation of Alfven eigenmodes and filaments that were the first of their kind and that provided important and novel results. Apart from that, the specific aspects of DBS application on a spherical tokamak are discussed. An in-depth look into the gradual change and improvement of the DBS diagnostics on Globus-M is also presented in this paper.

This review summarizes published information concerning the determination of antioxidant activity (AA) in coffee samples by various methods (ORAC, FRAP, TRAP, TEAC, etc.) in vitro and limited data of antiradical activity of coffee products in vitro and in vivo. Comparison is carried out of the AA of coffee Arabica and coffee Robusta roasted at different temperatures as well as by different roasting methods (microwave, convection, etc.). Data on the antiradical activity of coffee is provided. The antioxidant activity of coffee, tea, cocoa, and red wine is compared. At the end of this review, the total antioxidant content (TAC) of coffee samples from 21 coffee-producing countries as measured by an amperometric method is provided. The TAC of green and roasted coffee beans is also compared.

Antioxidants are substances that prevent oxidation of other compounds or neutralize free radicals. Spices and herbs are rich sources of antioxidants. They have been used in food and beverages to enhance flavor, aroma and color. Due to their excellent antioxidant activity, spices and herbs have also been used to treat some diseases. In this review article, the chemical composition and antioxidant activity of spices and culinary herbs are presented. The content of flavonoids and total polyphenols in different spices and herbs are summarized. The applications of spices and their impacts on human health are briefly described. The extraction and analytical methods for determination of antioxidant capacity are concisely reviewed.