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The most significant source of human exposure to ionizing radiation is the radioactive gas radon (basically 222Rn) and its daughter decay products, creating more than half of the effective dose from all natural sources. Radon enters buildings mainly from dense rocks, which are below building foundations at depths of 1 m and more. In this paper long-term measurements of radon flux density are analyzed, with radon exhalation from the surface of the most common rocks—loams, sandy loams, clays, clay shales, several types of sandy-gravel-pebble deposits, clay and rocky limestone. The influence of geophysical properties of rocks on radon flux density due to exhalation from surfaces of those rocks was studied. Based on the results obtained, a method of local assessment of the hazard from radon and its progeny in buildings is proposed, which is based on the geophysical properties of rocks below the foundations of those buildings. [ABSTRACT FROM AUTHOR]

This paper investigates the evolution of the Ukrainian stock market through an analysis of various data properties, including persistence, volatility, normality, and resistance to anomalies for the case of daily returns from the PFTS stock index spanning 1995–2022. Segmented into sub-periods, it aims to test the hypothesis that the market's efficiency has increased over time. To do this different statistical techniques and methods are used, including R/S analysis, ANOVA analysis, regression analysis with dummy variables, t-tests, and others. The findings present a mixed picture: while volatility and persistence demonstrate a general decreasing trend, indicating a potential shift towards a more efficient market, normality tests reveal no discernible differences between analyzed periods. Similarly, the analysis of anomalies shows no specific trends in the market's resilience to the day-of-the-week effect. Overall, the results suggest a lack of systematic changes in data properties in the Ukrainian stock market over time, possibly due to the country's volatile conditions, including two revolutions, economic crises, the annexation of territories, and a Russian invasion leading to the largest war in Europe since WWII. The limited impact of reforms and changes justifies the need for continued market reform and evolution post-war. [ABSTRACT FROM AUTHOR]

The development of a computational model of an induction motor with ring windings (IMRWs) for processing of nuclear waste is considered. At the first stage of the work, the overload capacity of the computational model of an IMRW was analyzed using the finite element method, the calculation being carried out in stages, taking into account the production and physical features of the IMRW prototype design. The IMRW model takes into account the influence of the oxide film on stator core sheets, technological gaps, eddy currents, and temperature conditions of the stator and rotor windings on the overload capacity of the IMRW. At the second stage, the mechanical characteristics of the IMRW were analytically calculated in the Ansys program using the parameters of the equivalent circuit determined by analyzing the design model of the motor. The calculated mechanical characteristics of an IMRW obtained by the finite element method and analytical calculation are compared with the results of testing the prototype. [ABSTRACT FROM AUTHOR]

Differences in the behaviour of asset prices depending on data frequency have not been thoroughly investigated in the literature despite their possible importance. In particular, high-frequency data might contain more information about financial assets because they are updated more rapidly in response to news. This paper explores persistence in high-frequency data (and also daily and monthly ones) in the case of the EuroStoxx 50 futures prices over the period from 2002 to 2018 (720 million trade records) using R/S analysis and the Hurst exponent as a measure of persistence. The results show that persistence is sensitive to the data frequency. More specifically, monthly data are highly persistent, daily ones follow a random walk, and intraday ones are anti-persistent. In addition, persistence varies over time. These findings imply that the Efficient Market Hypothesis (EMH) only holds in the case of daily data, whilst it is possible to make abnormal profits using trading strategies based on reversal strategies at the intraday frequency. [ABSTRACT FROM AUTHOR]

Complex immunosuppressive therapy is prescribed in medical practice to patients with glomerulonephritis to help them overcome symptoms and prevent chronic renal failure. Such an approach requires long-term systemic administration of strong medications, which causes severe side effects. This work shows the efficiency of polymer capsule accumulation (2.8 ± 0.4 µm) containing labeled etanercept (100 μg per dose) in the kidneys of mice. The comparison of injection into the renal artery and tail vein shows the significant superiority of the intra-arterial administration strategy. The etanercept retention rate of 18% and 8% ID in kidneys was found 1 min and 1 h after injection, respectively. The capsules were predominantly localized in the glomeruli after injection in mice using a model of acute glomerulonephritis. Histological analysis confirmed a significant therapeutic effect only in animals with intra-arterial administration of microcapsules with etanercept. The proposed strategy combines endovascular surgery and the use of polymer microcapsules containing a high molecular weight drug that can be successfully applied to treat a wide range of kidney diseases associated with glomerular pathology. [ABSTRACT FROM AUTHOR]

This paper examines price effects related to witching days in the US stock market using both weekly and daily data for three major indices, namely the Dow Jones, S&P500 and Nasdaq, over the period 2000–2021. First it analyses whether or not anomalies in price behaviour arise from witching by using various parametric (Student's t-test, and ANOVA) and non-parametric (Mann-Whitney) tests as well as an event study method and regressions with dummies; then it investigates whether or not any detected anomalies give rise to profit opportunities by applying a trading simulation approach. The results suggest the presence of the anomaly in daily returns on witching days which can be exploited by means of suitably designed trading strategies to earn abnormal profits, especially in the case of the Nasdaq index. Such evidence is inconsistent with the Efficient Market Hypothesis (EMH). [ABSTRACT FROM AUTHOR]

This paper uses R/S (Rescaled Range) analysis and fractional integration techniques to examine the persistence of two sets of 12 ESG (Environmental, Social and Governance) and conventional stock price indices from the MSCI ((Morgan Stanley Capital International) database over the period 2007–2020 for a large number of both developed and emerging markets. Both sets of results imply that there are no significant differences between the two types of indices in terms of the degree of persistence and its dynamic behaviour. However, higher persistence is found for the emerging markets examined (especially the BRICS, i.e. Brazil, Russia, India, China and South Africa), which suggests that they are less efficient and thus offer more opportunities for profitable trading strategies. Possible explanations for these findings include different type of companies' 'camouflage' and 'washing' (green, blue, pink, social, and Sustainable Development Goals—SDG) in the presence of rather lax regulations for ESG reporting. [ABSTRACT FROM AUTHOR]

This paper explored sustainability transparency and SDGs 2 and 12 disclosure and its influence on their overall efficiency, using data from Ukrainian agricultural companies. To do this Sustainability Transparency Index (STI) methodology is developed and used. The following hypothesis is tested: the higher the STI score is, the better position of the company is among its peers. For these purposes, STI index is calculated for the top100 Ukrainian agriculture companies. Correlation analysis, Granger causality tests and regression analysis provide evidences in favour of high dependence of position in top100 from the STI score: the more efforts companies invest into Sustainability Transparency, the higher the position in ranking is. This is direct evidence that companies' sustainability transparency is an important element of its activity nowadays. Recommendations to improve sustainability transparency based on suitable reporting practices are provided in this paper. [ABSTRACT FROM AUTHOR]

Infectious sequelae caused by surgery are a significant problem in modern medicine due to their reduction of therapeutic effectiveness and the patients' quality of life.Recently, new methods of local antimicrobial prophylaxis of postoperative sequelae have been actively developed. They allow high local concentrations of drugs to be achieved, increasing the antibiotic therapy's effectiveness while reducing its side effects. We have developed and characterized antimicrobial hydrogels based on an inexpensive and biocompatible natural substance from the dairy industry—whey protein isolate—as matrices for drug delivery. The release of cefazolin from the pores of hydrogel structures directly depends on the amount of the loaded drug and occurs in a prolonged manner for three days. Simultaneously with the antibiotic release, hydrogel swelling and partial degradation occurs. The WPI hydrogels absorb solvent, doubling in size in three days and retaining cefazolin throughout the duration of the experiment. The antimicrobial activity of cefazolin-loaded WPI hydrogels against Staphylococcus aureus growth is prolonged in comparison to that of the free cefazolin. The overall cytotoxic effect of cefazolin-containing WPI hydrogels is lower than that of free antibiotics. Thus, our work shows that antimicrobial WPI hydrogels are suitable candidates for local antibiotic therapy of infectious surgical sequelae. [ABSTRACT FROM AUTHOR]

The problem of reducing the side effects associated with drug distribution throughout the body in the treatment of various kidney diseases can be solved by effective targeted drug delivery. The method described herein involves injection of a drug encapsulated in polyelectrolyte capsules to achieve prolonged local release and long-term capillary retention of several hours while these capsules are administered via the renal artery. The proposed method does not imply disruption (puncture) of the renal artery or aorta and is suitable for long-term chronic experiments on mice. In this study, we compared how capsule size and dosage affect the target kidney blood flow. It has been established that an increase in the diameter of microcapsules by 29% (from 3.1 to 4.0 μ m) requires a decrease in their concentration by at least 50% with the same suspension volume. The photoacoustic method, along with laser speckle contrast imaging, was shown to be useful for monitoring blood flow and selecting a safe dose. Capsules contribute to a longer retention of a macromolecular substance in the target kidney compared to its free form due to mechanical retention in capillaries and slow impregnation into surrounding tissues during the first 1–3 h, which was shown by fluorescence tomography and microscopy. At the same time, the ability of capillaries to perform almost complete "self-cleaning" from capsular shells during the first 12 h leads to the preservation of organ tissues in a normal state. The proposed strategy, which combines endovascular surgery and the injection of polymer microcapsules containing the active substance, can be successfully used to treat a wide range of nephropathies. [ABSTRACT FROM AUTHOR]

This paper explores price (momentum and contrarian) effects and their timing parameters on the days characterised by abnormal returns and the following ones in two commodity markets. Specifically, using daily gold and oil price data over the period 01.01.2009–31.03.2020 the following hypotheses are tested: (H1) there is a time gap between the detection of an abnormal return day and the end of that day, (H2) there are price effects on the day after abnormal returns occur; (H3) price effects after 1-day abnormal returns have identifiable timing parameters; (H4) the detected timing parameters can be used to "beat the market". For these purposes average analysis, t tests, CAR and trading simulation approaches are used. The main results can be summarised as follows. Prices tend to move in the direction of abnormal returns till the end of the day when these occur. The presence of abnormal returns can usually be detected before the end of the day by estimating specific timing parameters, and a momentum effect can be detected. On the following day two different price patterns are detected: a momentum effect for oil prices and a contrarian effect for gold prices, respectively. These effects are limited in time, and the corresponding timing parameters are estimated. Trading simulations show that these effects can be exploited to generate abnormal profits with an appropriate calibration of the timing parameters. [ABSTRACT FROM AUTHOR]

This paper investigates the degree of persistence in the financial markets' data during different days of the week over the last twenty years. This allows taking a brand new look on the day-of-the-week effect and providing additional evidence against the efficient market hypothesis. The variety of the financial markets includes developed and emerging stock markets, FOREX, commodity and cryptocurrency markets. To measure the level of persistence the R/S analysis is used. The findings indicate that the level of persistence is different for different days of the week. This is inconsistent with the Efficient Market Hypothesis: data do not follow a random walk; and there can be indirect evidence in favor of the day-of-the-week effect. Conclusions on non-randomness of the data are important, because they allow choosing the best model to describe price dynamics so that to increase the predictive power of the existing models. Differences in the long-memory properties of the market data during different days of the week is an important finding that can lead to better understanding of the behavior of financial markets. High level of persistence implies data predictability, and therefore suggests that trend following technics can be applied to make profits from trading. [ABSTRACT FROM AUTHOR]

One of the promising materials for biophotonics and medicine, used for the diagnosis and targeted therapy of cancer, are silver sulfide nanoparticles. Molecular mechanisms of protein structures interaction with metal salts during the nanoparticles bacterial synthesis were studied by molecular modeling using the density functional theory methods. The peculiarity of obtaining silver sulfide nanoparticles by biosynthesis using bacteria Bacillus subtilis 168 is that the only flagellin protein involved in the synthesis process and adsorbed on the surface of the particles. Investigated objects are salts: silver nitrate AgNO3 and sodium thiosulfate Na2S2O3, which are involved in the synthesis process, and non-standard amino acid methyllysine as a part of flagellin. The simulation was based on formed molecular structures and its IR spectra calculation by Gaussian 09 software package. During the analysis of the formed hydrogen bonds parameters, it was found that methyllysine forms sufficiently stable molecular complexes with silver nitrate and sodium thiosulfate. This indicates the significant role of methyllysine in biogenic silver sulfide nanoparticles formation and clarifies the mechanism of its functioning as a part of flagellin. [ABSTRACT FROM AUTHOR]

Purpose: This paper explores abnormal price changes in the FOREX by using both daily and intraday data on the EURUSD, USDJPY, USDCAD, AUDUSD and EURJPY exchange rates over the period 01.01.2008–31.12.2018. Design/methodology/approach: It applies a dynamic trigger approach to detect abnormal price changes and then various statistical methods, including cumulative abnormal returns analysis, to test the following hypotheses: the intraday behaviour of hourly returns on overreaction days is different from that on normal days (H1), there are detectable patterns in intraday price dynamics on days with abnormal price changes (H2) and on the following days (H3). Findings: The results suggest that there are statistically significant differences between intraday dynamics on days with abnormal price changes and normal days respectively; also, prices tend to change in the direction of the abnormal change during that day, but move in the opposite direction on the following day. Finally, there exist trading strategies that generate abnormal profits by exploiting the detected anomalies, which can be seen as evidence of market inefficiency. Originality/value: New evidence on abnormal price changes and related trading strategies in the FOREX. [ABSTRACT FROM AUTHOR]

This paper examines whether there exists a momentum effect after one-day abnormal returns in the cryptocurrency market. For this purpose, a number of hypotheses of interest are tested for the Bitcoin, Ethereum and Litecoin exchange rates vis-à-vis the US dollar over the period 01.01.2015–01.09.2019, specifically whether or not: (H1) the intraday behavior of hourly returns is different on abnormal days compared to normal days; (H2) there is a momentum effect on days with abnormal returns, and (H3) after one-day abnormal returns. The methods used for the analysis include various statistical methods as well as a trading simulation approach. The results suggest that hourly returns during the day of positive/negative abnormal returns are significantly higher/lower than those during the average positive/negative day. The presence of abnormal returns can usually be detected before the day ends by estimating specific timing parameters. Prices tend to move in the direction of the abnormal returns till the end of the day when it occurs, which implies the existence of a momentum effect on that day giving rise to exploitable profit opportunities. This effect (together with profit opportunities) is also observed on the following day. In two cases (BTCUSD positive abnormal returns and ETHUSD negative abnormal returns), a contrarian effect is detected instead. [ABSTRACT FROM AUTHOR]

Using molecular modeling by the density functional theory B3LYP method with 6-31 G(d) basic set, we analyse the hydrogen bonds formation and their influence on IR-spectra and structure of molecular complexes which is formed due to interaction between nanodiamonds with COOH- surface functionalization and highly toxic drugs on example of doxorubicin and mitoxantrone. Molecular modeling of modificated nanodiamonds and drugs interaction is based on nanodiamond representation by a diamond-like nanoparticle with simpler structure. As a result of calculations the combined IR spectrum is obtained as imposing of IR spectra for molecular complexes of drugs and nanodiamonds in various interaction positions. Combined IR spectra demonstrate a good agreement with experimental data. Received results demonstrate that there can be strong supramolecular interaction between drugs and modificated detonation nanodiamonds. Formed hydrogen bonds can be considered as one of the main mechanisms for targeted drug delivery and for drug retention in cells and, thus, for enhancement of anti-cancer therapeutic efficacy. [ABSTRACT FROM AUTHOR]

This paper examines long-term price overreactions in various financial markets (commodities, US stock market and FOREX). First, a number of statistical tests are carried out for overreactions as a statistical phenomenon. Second, a trading robot approach is applied to test the profitability of two alternative strategies, one based on the classical overreaction anomaly, the other on a so-called "inertia anomaly". Both weekly and monthly data are used. Evidence of anomalies is found predominantly in the case of weekly data. In the majority of cases strategies based on overreaction anomalies are not profitable, and therefore the latter cannot be seen as inconsistent with the EMH. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to examine price overreactions in the case of the following cryptocurrencies: bitcoin, litecoin, ripple and dash. Design/methodology/approach: A number of parametric (t-test, ANOVA, regression analysis with dummy variables) and non-parametric (Mann–Whitney U-test) tests confirm the presence of price patterns after overreactions: the next day price changes in both directions are bigger than after "normal" days. A trading robot approach is then used to establish whether these statistical anomalies can be exploited to generate profits. Findings: The results suggest that a strategy based on counter-movements after overreactions is not profitable, whilst one based on inertia appears to be profitable but produces outcomes not statistically different from the random ones. Therefore, the overreactions detected in the cryptocurrency market do not give rise to exploitable profit opportunities (possibly because of transaction costs) and cannot be seen as evidence against the efficient market hypothesis (EMH). Originality/value: The overreactions detected in the cryptocurrency market do not give rise to exploitable profit opportunities (possibly because of transaction costs) and cannot be seen as evidence against the EMH. [ABSTRACT FROM AUTHOR]

This paper investigates persistence in financial time series at three different frequencies (daily, weekly and monthly). The analysis is carried out for various financial markets (stock markets, FOREX, commodity markets) over the period from 2000 to 2016 using two different long memory approaches (R/S analysis and fractional integration) for robustness purposes. The results indicate that persistence is higher at lower frequencies, for both returns and their volatility. This is true of the stock markets (both developed and emerging) and partially of the FOREX and commodity markets examined. Such evidence against the random walk behaviour implies predictability and is inconsistent with the Efficient Market Hypothesis (EMH), since abnormal profits can be made using trading strategies based on trend analysis. [ABSTRACT FROM AUTHOR]

This paper investigates the role of the frequency of price overreactions in the cryptocurrency market in the case of BitCoin over the period 2013–2018. Specifically, it uses a static approach to detect overreactions and then carries out hypothesis testing by means of a variety of statistical methods (both parametric and non-parametric) including ADF tests, Granger causality tests, correlation analysis, regression analysis with dummy variables, ARIMA and ARMAX models, neural net models, and VAR models. Specifically, the hypotheses tested are whether or not the frequency of overreactions (i) is informative about Bitcoin price movements (H1) and (ii) exhibits no seasonality (H2). On the whole, the results suggest that it can provide useful information to predict price dynamics in the cryptocurrency market and for designing trading strategies (H1 cannot be rejected), whilst there is no evidence of seasonality (H2 cannot be rejected). [ABSTRACT FROM AUTHOR]

As a result of an experimental study of the Raman scattering valence bands of water in aqueous suspensions of detonation nanodiamonds with different functional surface groups, the energies of hydrogen bonds in suspensions of nanoparticles were calculated for the first time. It is shown that the degree of influence of different functional surface groups of nanodiamonds on hydrogen bonds in aqueous suspension decreases in the series H > polyfunctional surface > OH > COOH. The obtained data are confirmed by modeling of optimized nanodiamond structures in water clusters and theoretical calculations of the bond parameters in these structures by the density functional theory. As a result of an experimental study of the Raman scattering valence bands of water in aqueous suspensions of detonation nanodiamonds with different functional surface groups, the energies of hydrogen bonds in suspensions of nanoparticles were calculated for the first time. The obtained data are confirmed by modeling of optimized nanodiamond structures in water clusters and theoretical calculations of the bond parameters in these structures by the density functional theory. [ABSTRACT FROM AUTHOR]

This paper investigates persistence in Ukrainian financial data during the recent local crisis of 2013-2015. Using R/S analysis with the Hurst exponent method and its dynamic modification we show that data properties (case of persistence) are unstable and vary over time. Persistence increases dramatically during the crisis periods. These results can be used both to predict crises at early stages and to model financial data with the appropriate methods: to determine models for the cases of persistent data and stochastic ones for the cases of nonpersistent data. It is concluded that financial markets become less efficient during crises. [ABSTRACT FROM AUTHOR]

This paper examines short-term price reactions after one-day abnormal price changes and whether they create exploitable profit opportunities in various financial markets. Statistical tests confirm the presence of overreactions and also suggest that there is an “inertia anomaly”, i.e. after an overreaction day prices tend to move in the same direction for some time. A trading robot approach is then used to test two trading strategies aimed at exploiting the detected anomalies to make abnormal profits. The results suggest that a strategy based on counter-movements after overreactions does not generate profits in the FOREX and the commodity markets, but in some cases it can be profitable in the US stock market. By contrast, a strategy exploiting the “inertia anomaly” produces profits in the case of the FOREX and the commodity markets, but not in the case of the US stock market. [ABSTRACT FROM AUTHOR]

Extracts of S. maximum and S. telephium showed antimicrobial activity against Staphylococcus aureus ATCC 6538P, Pseudomonas aeruginosa ATCC 27835, and Escherichia coli ATCC 25922. The EtOH extract of S. maximum that was not purified by CHCl was most efficacious. The flavonoid contents in the extracts and their antimicrobial activities were correlated. [ABSTRACT FROM AUTHOR]

This paper tests for the presence of the Friday effect in various financial markets (stock markets, FOREX, and commodity markets) by using a number of statistical techniques (average analysis, parametric tests such as Student's ttest and ANOVA analysis, non-parametric ones such as the Kruskal-Wallis test, regression analysis with dummy variables). The evidence suggests that stock markets are immune to Friday effects, whilst in the FOREX Fridays exhibit higher volatility, and in the Gold market returns are higher on this day of the week. Using a trading robot approach we show that the latter anomaly can be exploited to make abnormal profits. [ABSTRACT FROM AUTHOR]

This paper develops a new pair trading method to detect inefficiencies in exchange rates movements and arbitrage opportunities using a convergence/divergence indicator (CDI) belonging to the oscillatory class. The proposed technique is applied to 11 exchange rates over the period 2010-2015, and trading rules based on CDI signals are obtained. The CDI indicator is shown to outperform others of the oscillatory class and in some cases (for EURAUD and AUDJPY) to generate profits. The suggested approach is of general interest and can be applied to different financial markets and assets. [ABSTRACT FROM AUTHOR]

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A new NICA heavy-ion collider is now under construction at JINR. At the same time, the Nuclotron facility is being modernized. A joint team from the JINR, MEPhI, and ITEP are now reconstructing a proton and light-ion injection system. New results of the RFQ linac resonator testing and measurements and RF power load are discussed in this article. [ABSTRACT FROM AUTHOR]

Purpose The purpose of this paper is to provide some new empirical evidence on the weekend effect (one of the best known anomalies in financial markets) in Ukrainian futures prices. The analysis uses various statistical techniques.Design/methodology/approach The analysis uses various statistical techniques (average analysis, Student’s t-test, dummy variables, and fractional integration) to test for the presence of this anomaly, and then a trading simulation approach to establish whether it can be exploited to make extra profits.Findings The statistical evidence points to abnormal positive returns on Fridays, and a trading strategy based on this anomaly is shown to generate annual profits of up to 25 per cent. The implication is that the Ukrainian stock market is inefficient.Originality/value This paper provides some new empirical evidence on the weekend effect (one of the best known anomalies in financial markets) in Ukrainian futures prices. The analysis uses various statistical techniques (average analysis, Student’s t-test, dummy variables, and fractional integration) to test for the presence of this anomaly, and then a trading simulation approach to establish whether it can be exploited to make extra profits. The statistical evidence points to abnormal positive returns on Fridays, and a trading strategy based on this anomaly is shown to generate annual profits of up to 25 per cent. The implication is that the Ukrainian stock market is inefficient. [ABSTRACT FROM AUTHOR]

This paper examines persistence in the Ukrainian stock market during the recent financial crisis. Using two different long memory approaches (R/S analysis and fractional integration) we show that this market is inefficient and the degree of persistence is not the same at different stages of the financial crisis. Therefore trading strategies might have to be modified. We also show that data smoothing is not advisable in the context of R/S analysis. [ABSTRACT FROM AUTHOR]

One of the leading criticisms of the efficient market hypothesis is the presence of so-called 'anomalies', i.e. empirical evidence of abnormal behaviour of asset prices which is inconsistent with market efficiency. However, most studies do not take into account transaction costs. Their existence implies that in fact traders might not be able to make abnormal profits. This paper examines whether or not anomalies such as intraday or time of the day effects give rise to exploitable profit opportunities by replicating the actions of traders. Specifically, the analysis is based on a trading robot which simulates their behaviour, and incorporates variable transaction costs (spreads). The results suggest that trading strategies aimed at exploiting daily patterns do not generate extra profits. Further, there are no significant differences between sub-periods (2005-2006-'normal'; 2007-2009-'crisis'; 2010-2011-'post-crisis). [ABSTRACT FROM AUTHOR]