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International audience; It is recognized that the filaments have a significant effect on the anomalous energy and particle transport in the tokamak periphery. They are actively investigated using various diagnostics in this regard. Recently studies of filaments using the Doppler backscattering (DBS) method have been performed in the Globus-M and the ASDEX-Upgrade tokamaks. Backscattering from filaments manifests itself as a burst of quasi-coherent fluctuations (BQF) of the signals of IQ detectors. Such signals are easy to describe in the Born approximation using the diagnostic weighting function. However, the filaments in tokamaks differ noticeably in their size and intensity. With an increase in the amplitude of the filaments, it is necessary to consider the transition from linear scattering to nonlinear one and further up to the transition from backscattering to reflection from a moving over dens filament. This problem can be solved only using a full wave code. Our simulation was carried out using the finite-difference time-domain code IPF-FD3D in slab geometry. We did not resort to using well-known non-linear MHD codes to determine filament parameters. In the simulation artificial filament-like perturbations were used, the parameters of which varied over a wide range. Modeling DBS signal was focused on the identification of the influence of the amplitude of the filament and its size on the shape and the size of the DBS output signal. The results obtained largely explain the similarity of the IQ detector data registered in different tokamaks.

This study presents the determination of the total antioxidant capacity (TAC) in twenty edible plants traditionally considered as having pro-health properties and commonly found in East Asia and the Middle East. The aim of the study was to apply a flow-injection amperometric detector (Blizar antioxidant analyzer) for rapid measurement of TAC. Three extraction solvents were used (water, 40% ethanol and 96% ethanol). On average, the edible plants that presented the highest TAC [expressed as gallic acid equivalents (GAE)] for the three extraction solvents were Rosa rugosa (34 mg/g GAE), Scutellaria baicalensis (22.9 mg/g GAE), Forsythia suspensa (11.7 mg/g GAE), Carthamus tinctorius (11.5 mg/g GAE), Smilacis glabrae rhizoma (10.8 mg/g GAE), Citri reticulatae pericarpium (8.8 mg/g GAE), Apocynum venetum (7.6 mg/g GAE) and Glycyrrhiza uralensis (7.5 mg/g GAE). This investigation contributes to the current knowledge on the overall antioxidant activity of edible plants traditionally consumed for expected pro-health properties, identifying specimens exhibiting high TAC determined by a rapid and low cost amperometric method.

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.

Low-value by-products can be processed using biotechnological methods, which seems to be the optimal solution for the problem of rational use of secondary raw materials. The authors introduce a method of biotransformation using whey and enzyme preparation of proteolytic action with subsequent massaging. The method neutralizes the specific smell, reduces the time of heat treatment, increases hydrophilicity, and reduces the mechanical strength of mutton rumen tissue. The experiment proved that the enzymatic effect on the connective tissue of the mutton rumen contributes to the destruction of disulfide and hydrogen bonds of the triple helix of the collagen macromolecule. It significantly reduces the mechanical strength and hydrothermal stability of collagen, which, in its turn, reduces the heat treatment time while increasing the functional and technological properties. The research revealed an increase in collagen digestibility. After 4 hours of fermentation, it was 4.5%, after 6 hours – 5.9%, and after 8 hours – 5.9%. Hence, the optimal period of fermentation was determined as 6 hours, since between 6 and 8 hours the main physical and chemical parameters improved insignificantly. The experiment in the cutting pressure of the raw lamb rumen tissue demonstrated softening of the structure as a result of the effect of the acidic medium on the collagen structure. An excess positive charge formed due to the suppression of dissociation of carboxyl groups of side chains. The loosening of the collagen structure occurred due to the expansion of fibrils in the polar areas, which can be attributed to the repulsion between similarly charged groups. As a result, the brine penetrated into the expanded area and caused swelling. The use of whey and fermentation contributed to an additional increase in moisture-binding and moisture-holding capacity. It loosened the structure of proteins and, thus, increased the degree of penetration and the immobilized moisture in the rumen. As a result, its mass increased by 10–20%, and the heat loss reduced. The composition of the brine contributed to the swelling, increased the diameter of the collagen fibers, and enlarged the surface of interaction in during massaging. Moisture was allowed to enter freely, which increased the water binding capacity by 22.2 ± 0.31%. The increase in the water binding capacity could be explained by the modification of collagen and its destructive changes. The changes occurred due to the additional interaction of whey molecules with the protein and the formation of new intermolecular bonds. Fermentation, combined with the massaging of the tripe, contributed to the development of lactic microflora and hydrolytic decomposition of protein components, thereby reducing the heat treatment process. Such changes are associated not only with the processes of protein hydrolysis under enzyme preparation, but also with the complex activity of lactic acid bacteria, as well as endo- and exoenzymes that hydrolyze proteins. The changes can also be attributed to the fact that low-molecular protein substances can assimilate and contribute to bacterial growth. In addition, lactic acid reduces the pH of the medium, thus activating the enzymatic properties. The proposed method of biotransformation of collagen-containing raw materials makes it possible to create environmentally friendly and low-waste technologies.

В кратком обзоре приведены основные данные о портативных жидкостных хроматографах: истории появления, состав, применяемые детекторы, колонки, насосы и области применения. Приведен перечень коммерческих портативных жидкостных хроматографов. Миниатюризация приборов - одна из основных тенденций развития в хроматографии. Основные области применения портативных жидкостных хроматографов - это анализ на месте события или происшествия: это контроль окружающей среды, пищевых продуктов на рынках и супермаркетах, клинические анализы у постели больного, судебно-токсикологические анализы и др. Портативные жидкостные хроматографы должны иметь небольшой размер и вес, должны работать автономно и надежно, иметь низкое потребление электроэнергии и расходных материалов. Основные детекторы, используемые в портативных жидкостных хроматографах - УФ на светодиодах и электрохимические. Основной толчок развитию портативных жидкостных хроматографов дала разработка портативного электроосмотического насоса высокого давления. В портативных жидкостных хроматографах используются наноколонки, капиллярные колонки и микронасадочные колонки. В некоторых случаях используется даже градиентное элюирование. Около десяти фирм начали разработку или уже выпускают портативные жидкостные хроматографы для биоанализов, диагностики заболеваний, контроля загрязнений. В качестве детекторов, кроме вышеупомянутых, стали использоваться масс-спектрометрические, флуориметрические и хемилюминесцентные. Несомненно, следует ожидать новых портативных жидкостных хроматографов.

The work presents the results of the energy confinement study carried out on the compact spherical tokamak Globus-M2 with a toroidal magnetic field as high as 0.8 T. A reproducible and stable discharge was obtained with the average plasma density (5–10) × 1019 m−3. Despite the increase in the magnetic field, the neutral beam injection (NBI) led to clear and reproducible transition to the H-mode accompanied by a decrease in the turbulence level at the plasma edge. NBI allowed effectively heat the plasma: electron and ion temperatures in the plasma core exceeded 1 keV. Compared to the previous experiments carried out with a toroidal magnetic field as high as 0.4 T plasma total stored energy was increased by a factor of 4. The main reason or this phenomenon is a strong dependence of the energy confinement time on the toroidal magnetic field in the spherical tokamak. It was experimentally confirmed that such kind of dependence is valid for ST with magnetic field up to 0.8 T. It has also been shown that the enhancement of the energy confinement in Globus-M2 with collisionality decrease is associated with an improvement of both electron and ion thermal insulation.

Purpose The purpose of this paper is to determine the antioxidant activity of natural polyphenols from larch wood by the amperometric method. Design/methodology/approach Direct measurements of antioxidant activity were carried out by the amperometric method in an oxidizing mode with glassy carbon as a working electrode, set potential +1.3V and using a flow-injection system with 2.2 mM phosphoric acid as the mobile phase with a flow rate of 1.2 ml/min. Findings The reported results show the following values of antioxidant activity for the tested compounds: (−)-secoisolariciresinol – 0.199 ± 0.002 mg/L (p < 0.05); isolariciresinol – 0.196 ± 0.002 mg/L (p < 0.05); lariciresinol - 0.222 ± 0.001 mg/L (p < 0.05); O-isopropylidene derivative of (−)-secoisolariciresinol - 0.143 ± 0.002 mg/L (p < 0.05); (+)-dihydroquercetin – 0.153 ± 0.002 mg/L (p < 0.05); and quercetin – 0.521 ± 0.001 mg/L (p < 0.05). The last product was tested as the reference of a widely used current antioxidant. General tendencies of determined values of antioxidant activity for studied compounds are in good correlation with published data as determined by the t-BuOOH-initiated lipid peroxidation method. Practical implications Described results show practical applicability of the amperometric method as being faster and cheaper in comparison to other methods, including oxygen radical absorbance capacity (ORAC) assay or 2,2′diphenyl-1-picrylhydrazyl (DPPH) reagent based assay. Originality/value The described results show the first-time application of the amperometric method for the evaluation of the antioxidant activity of phenolic compounds from larch wood.

Radial electric field shear is crucial for turbulence suppression and transition to the H-mode, although the high shear value alone may not be sufficient for the LH-transition initiation. Temporal and spatial parameters of shear perturbation, particle source and turbulence parameters are the main factors responsible for LH-transition initiation. Different plasma discharge scenarios in two Ioffe Institute conventional tokamaks are analyzed using the model of plasma density and ion temperature evolution to clear up the role of aforementioned factors.Radial electric field shear is crucial for turbulence suppression and transition to the H-mode, although the high shear value alone may not be sufficient for the LH-transition initiation. Temporal and spatial parameters of shear perturbation, particle source and turbulence parameters are the main factors responsible for LH-transition initiation. Different plasma discharge scenarios in two Ioffe Institute conventional tokamaks are analyzed using the model of plasma density and ion temperature evolution to clear up the role of aforementioned factors.

In the H-mode discharges with the neutral beam heating (NBI) in the Globus-M tokamak the sawtooth oscillations are triggering the edge localised modes (ELM) onset. The triggered ELMs have the magnetic oscillation precursor less than 0.2 ms before the onset with the typical island rotation frequency. The paper discussing the peeling-ballooning (P-B) destabilisation caused by the current density profile broadening due to partial reconnection.

Here we report the results of the turbulence study in the high confinement mode (H-mode) with and without edge localized modes (ELMs). The study was performed by the Doppler backscattering (DBS) method on the Globus-M tokamak. It was demonstrated that the transition from the H-mode with ELMs to the ELM-free H-mode is characterized by the drop of the turbulence intensity near the periphery.

The current work reports on the significant rise of the fusion triple product in experiments carried out on the compact spherical tokamak (ST) Globus-M2 with a twofold increase in the toroidal magnetic field. A tenfold rise in the n . T . τ E product was recorded during an increase in the magnetic field from 0.4 to 0.8 T and the plasma current from 0.25 to 0.4 MA at an unchanged auxiliary heating power value. Limited reasons may affect this positive trend, among which are energy confinement improvement and an increase in the efficiency of neutral beam heating. Despite the increase in the magnetic field, the neutral beam injection (NBI) led to clear and reproducible transition to the H-mode accompanied by a decrease in the turbulence level at the plasma edge. It was experimentally confirmed that strong dependence of the energy confinement time on the magnetic field value is conserved at a higher magnetic field approaching 0.8 T. Enhancement of energy confinement is connected to a collisionality (ν *) decrease. While for conventional tokamaks the confinement dependence on collisionality becomes weaker with decreasing ν * dependence, in the ST, in contrast, we observe its strengthening.

This article considers a four-frequency microwave Doppler backscattering (DBS) system in the compact spherical tokamak Globus-M. The hardware was adequate for the purposes of studying the peripheral plasma in the tokamak. The multichannel DBS system is based on duplication of a dual homodyne detection circuit for four incident Ka-band frequencies. The ray tracing results for a spherical torus are described, and specific requirements for the antenna tilt adjustment are defined. Some new experimental results are given for using DBS diagnostics on the Globus-M tokamak in order to illustrate its efficiency.

Epidemiological studies have provided the evidence that regular consumption of fruits and vegetables reduce the risk of pathological condition such as cardiovascular disease, cancer, inflammation, and aging. Among fruits, berries are considered as superfruits due to their highly packed phytochemicals comprising phenolic acids, flavonoids viz. flavonols, flavanols, and anthocyanins. These bioactive compounds are associated with significant antioxidant, antidiabetic, antiinflammation, and anticancer properties. This review highlights the basic information and interesting findings of some selected commercial berries with their phytochemical composition, antioxidant properties, and potential health benefits to human.

A turbulence study was carried out on the Globus-M tokamak. The main method of turbulence studying was Doppler backscattering. Studies have been performed at different radii (in areas with different plasma parameters). It was found that during the transition from H-mode with edge localized modes (ELMs) to the improved confinement mode without ELMs, both turbulent fluctuations of the plasma density and velocity fluctuations are suppressed, which apparently leads to a decrease in anomalous transport.

We study an extension of superintuitionistic logic LC (Dummett logic, Logic of Chains) in the language containing an additional unary logical connective. This connective is interpreted on every finite chain by the so called irreflexive modality. We show that the resulting logic is conservative over LC, determines a new logical connective in LC w.r.t. P. Novikov’s approach to the notion of a new logical connective. Moreover, we show that is an explicit example of Novikov complete extension of LC, i.e. every proper extension of it is not conservative over LC.

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.

Polysaccharides are naturally occurring biomacromolecules composed of carbohydrate molecules linked by glycosidic bonds. A number of polysaccharides are known to possess beneficial therapeutic effects against inflammation, diabetes, cardiovascular diseases, and cancers. Indeed, polysaccharides are reportedly effective free radical scavengers and antioxidants, thereby playing a critical role in the prevention of damage to living organisms under oxidative stress. In this review we provide an overview of the sources, extraction, and antioxidant activities of some natural polysaccharides.

Numerous epidemiological studies indicate that consumption of antioxidant-rich foods is beneficial to human health and reduces the risks of dangerous diseases and premature aging. Among natural antioxidants some stand out for their powerful activity and health benefits and they are epigallocatechin gallate, quercetin, curcumin, resveratrol, hydroxytyrosol, astaxanthin, lycopene, dihydroquercetin, and lignans. Preclinical, clinical, and therapeutic studies of these antioxidants in their pure form or in their combination have shown positive health benefits. This review highlights basic information and interesting findings with their source, structure, antioxidant properties, and potential health benefits to human.

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.

Interest in antioxidants and antioxidant therapy has been growing during the last decade. Antioxidants are generally considered to have the capability to protect people from harmful effects of reactive oxygen and nitrogen species (RONSs), including free radicals (FR), when these are present in excessive amounts. RONS and free radicals perform a variety of useful biological functions in the body. Their excess is controlled by a natural antioxidant protection system in humans. This protection is provided at three levels: by simple molecules (such as cysteine, glutathione (GSH), uric acid, ubiquinol, etc.), medium-molecular weight, and high molecular weight compounds (enzymes, etc.). Under certain adverse conditions, this system does not manage to provide adequate protection and the RONSs and free radicals begin to damage vital DNA, proteins, and lipids. In such a case, antioxidant therapy, which includes antioxidant supplements and foods containing natural antioxidants, has been suggested to be of possible benefit. However, there are many unresolved issues related to the effective use of an antioxidant therapy: 1. A person should know the content of antioxidants in everyday food products and its relation to the storage time and processing methods used. 2. How many antioxidants should a person consume? It is known that at high concentrations some antioxidants become pro-oxidants. 3. Are the antioxidants consumed by a person bioavailable and, if so, to what extent; for some food products, bioavailability has already been determined but most foods have not been examined. 4. Many antioxidants are digested by intestinal microflora before they reach the systemic blood circulation. 5. Even those antioxidants that do reach the blood are often rapidly metabolized; the role of their metabolites is unclear; there is some evidence that certain metabolites are also antioxidants. 6. How long do antioxidants and their metabolites stay in the body; how are they distributed in different organs; and when are they excreted? In order to answer these questions, the pharmacokinetics of antioxidants should be studied. 7. The presence of oxidative stress, i.e., excess amounts of RONSs and free radicals, can be detected by various oxidative stress markers but, in order to see the whole picture, the actual concentrations of RONSs

Antioxidant activity of different types of tea (green, oolong, black, pu-erh ) were measured using different modern methods. Several types of commercially available teas, from various manufacturers were tested for antioxidant content using the amperometric method, the data is displayed here. Data gathered about antioxidant content of these different tea samples can be used to estimate quality and type of tea. The data collected using this method is also important when trying to account for the normal daily consumable antioxidant of healthy people and also patients using clinical antioxidant therapy.

Coffee has been one of the most commercialized food products and most widely researched beverage in the world for decades. It is considered a functional food, primarily due to its high content of compounds that exert antioxidant and other beneficial biological properties. This review summarized the data from analysis of coffee components, both volatile constituents and non-volatile high-molecular weight compounds performed by various chromatographic methods. A list of compounds identified by gas chromatography with mass spectrometry which define the aroma of coffee is provided. Publications on the measurement of methylxanthines (caffeine, theobromine, and theophylline), chlorogenic acids, diterpenes, sugars, amino acids, gamma-aminobutyric acid, dibasic acids, anions, and other compounds by HPLC and UHPLC-MS are reviewed. An overview of publications on the determination of organic contamination in coffee (PAHs, acrylamides, mycotoxins, etc.) and ways to reduce contamination through production technology and brewing methods are presented. Finally, an overview of the literature on authentication assessment for different grades of coffee grown in different regions is provided.

Extending the language of the intuitionistic propositional logic Int with additional logical constants, we construct a wide family of extensions of Int with the following properties: (a) every member of this family is a maximal conservative extension of Int; (b) additional constants are independent in each of them.

This review discusses the bioavailability of active components of green and black teas--in hot brewed tea, cold tea, and dietary supplements containing tea extracts, based on literature published in 1995-2011. Many publications demonstrate that consumption of tea increases the antioxidant status of a person (between 3.5-76%) and reduces the concentration of oxidative stress biomarkers in biological fluids. In 1-2 hours after tea intake, epigallocatechin gallate (EGCG), epicatechin (EC), and epicatechin gallate (ECG) at a level of 5-150 ng/ml were detected in plasma by HPLC. The results of pharmacokinetics and metabolism of biologically active tea components analyzed within 24 hours in plasma, urine, and feces by HPLC-MS and GC-MS are presented. Dozens of metabolites were identified in urine and plasma—these are methylated, sulfated, and glucuronide conjugates of catechins. Some metabolites were shown to have high antioxidant activity. The role of the small intestine and colon in absorption of catechins was also identified.

Multi-diagnostic approach developed for the GAM research in the spherical tokamak Globus M is described. Doppler backscattering (DBS) method as the tool for the GAM study, together with the diagnostics of plasma density and magnetic field GAM oscillations, were simultaneously used in experiments. The version of the DBS diagnostics with two cut-offs positioned at different poloidal angles of the minor cross-section was employed in Globus-M. For the GAM plasma density oscillation study, the Dα emission was observed at different angles to restore the spatial mode structure of the GAM plasma density oscillations. At the same time, the array of Mirnov coils was used for the GAM-like magnetic oscillation study, and that made it possible to restore the magnetic field perturbation spatial structure. The coherent and cross-bicoherence analyzes were employed to identify the interaction between the GAM velocity oscillation and plasma turbulent fluctuations. A shorter version of this contribution is due to be published in PoS at: 1st EPS conference on Plasma Diagnostics