Prvi nalaz glavoča nepoznatog Gobius incognitus (Actinopterygii: Gobiiformes: Gobiidae) na Malti

The first record of Gobius incognitus Kovačić & Šanda, 2016 was reported from Malta. Two specimens were collected at the island of Gozo and stored as unidentified in 2012, several years before the description of Gobius incognitus. A decade later the material was finally identified based on morphology and coloration pattern of preserved specimens. The habitat preferences and geographic distribution of this species are discussed.Prvi nalaz vrste Gobius incognitus zabilježen je za Maltu. Dva primjerka ove vrste sakupljena su na otoku Gozo još 2012. godine, prije opisa same vrste 2016. godine. Desetljeće poslije, materijal je određen pomoću morfologije i obojenja konzerviranih primjeraka. Raspravljeni su podaci o staništu i zemljopisnoj rasprostranjenosti ove vrste

Parliamentary-presidential or presidential-parliamentary republic as modes of one political model or different concepts of government

This research paper deals with the scientific research of institutional-procedural and behavioral attributes, principles and indicators of typology of mixed-type republics in European countries. The conducted scientific analysis gives grounds to argue that the defining directions in this context are the appeal to the problems of formation and activity of governments and the possibility of dissolving parliaments (ie scientific institutional and procedural differentiation of hybrid republican forms), dualism, legality and responsibility of executive bodies, as well as the index of presidential powers and the peculiarities of the dualism of the executive branch

Моделювання ринку криптовалют за допомогою фрактального та ентропійного аналізу в умовах COVID-19

In this article, we present the results of simulation for cryptocurrency market based on fractal and entropy analysis using six cryptocurrencies in the first 20 of the capitalization rating. The application of the selected research methods is based on an analysis of existing methodologies and tools of economic and mathematical modeling of financial markets. It has been shown that individual methods are not relevant because they do not provide an adequate assessment of the given market, so an integrated approach is the most appropriate. Daily values of cryptocurrency pairs from August 2016 to August 2020 selected by the monitoring and modelling database. The application of fractal analysis led to the conclusion that the time series of selected cryptocurrencies were persistent. And the use of the window procedure for calculating the local Hurst coefficient allowed to detail and isolate the persistant and antipersistant gaps. Interdisciplinary methods, namely Tsallis entropy and wavelet entropy, are proposed to complement the results. The results of the research show that Tsallis entropy reveals special (crisis) conditions in the cryptocurrency market, despite the nature of the crises’ origin. Wavelet entropy is a warning indicator of crisis phenomena. It provides additional information on a small scale.У цій статті ми представляємо результати моделювання ринку криптовалют на основі фрактального та ентропійного аналізу з використанням шести криптовалют у перших 20 рейтингу капіталізації. Застосування вибраних методів дослідження ґрунтується на аналізі існуючих методологій та інструментів економіко -математичного моделювання фінансових ринків. Було показано, що окремі методи не є актуальними, оскільки вони не забезпечують адекватної оцінки даного ринку, тому комплексний підхід є найбільш доцільним. Щоденні значення пар криптовалют з серпня 2016 року по серпень 2020 року, обрані базою даних моніторингу та моделювання. Застосування фрактального аналізу привело до висновку про постійність часових рядів обраних криптовалют. А використання віконної процедури для розрахунку локального коефіцієнта Херста дозволило деталізувати та ізолювати стійкі та антистійкі прогалини. Для доповнення результатів пропонуються міждисциплінарні методи, а саме ентропія Цаліса та вейвлет -ентропія. Результати дослідження показують, що ентропія Tsallis виявляє особливі (кризові) умови на ринку криптовалют, незважаючи на характер виникнення криз. Хвильова ентропія - попереджувальний індикатор кризових явищ. Він надає додаткову інформацію в невеликому масштабі

Modelling of Cryptocurrency Market Using Fractal and Entropy Analysis in COVID-19

У статті наведено результати моделювання ринку криптовалют методами фрактального та ентропійного аналізу на прикладі шести криптовалют, які займають перші позиції в 20-рейтингу капіталізації. Вибір та застосування обраних методів дослідження засновано на аналізі існуючих методологій та інструментів економічного та математичного моделювання фінансових ринків. Було доведено, що окремі методи не є релевантними, оскільки не забезпечують адекватної оцінки цього ринку, тому комплексний підхід є найбільш доцільним. В роботі використано добові значення криптовалютних пар із серпня 2016 року по серпень 2020 року з бази даних моніторингу та моделювання. Застосування фрактального аналізу дозволило дійти висновку, що часові ряди обраних криптовалют були стійкими. Використання процедури рухомого вікна для обчислення локального коефіцієнта Херста дозволило деталізувати та ізолювати стійкі та антиперсистентні розриви. Міждисциплінарні методи, а саме ентропія Цаліса та вейвлет-ентропія дозволили уточнити результати. Результати дослідження показують, що ентропія Цаліса виявляє особливі (кризові) умови на ринку криптовалют, незважаючи на характер виникнення кризи. Вейвлет-ентропія є попереджувальним показником кризових явищ. Вона надає додаткову інформацію на малих масштабахIn this article, we present the results of simulation for cryptocurrency market based on fractal and entropy analysis using six cryptocurrencies in the first 20 of the capitalization rating. The application of the selected research methods is based on an analysis of existing methodologies and tools of economic and mathematical modeling of financial markets. It has been shown that individual methods are not relevant because they do not provide an adequate assessment of the given market, so an integrated approach is the most appropriate. Daily values of cryptocurrency pairs from August 2016 to August 2020 selected by the monitoring and modelling database. The application of fractal analysis led to the conclusion that the time series of selected cryptocurrencies were persistent. And the use of the window procedure for calculating the local Hurst coefficient allowed to detail and isolate the persistant and antipersistant gaps. Interdisciplinary methods, namely Tsallis entropy and wavelet entropy, are proposed to complement the results. The results of the research show that Tsallis entropy reveals special (crisis) conditions in the cryptocurrency market, despite the nature of the crises’ origin. Wavelet entropy is a warning indicator of crisis phenomena. It provides additional information on a small scale

Measurement of Thermo-Radiation Characteristics of Spectral-Selective Materials for Space Structures Designs

The research demonstrates the relevance of creating the technologies of application of spectral-selective coatings of materials, intended for open space structures designs and the development of methods of control of their thermo-radiation characteristics. It is noted that under other equal conditions, the temperature of the surface of a structure in the vacuum of the outer space is determined by the ratio of the absorption coefficient of solar radiation to the emission factor of the surface. The aim of the work is to demonstrate the perspective of calorimetric measurements of thermo-radiation characteristics without vacuuming the volume of the measuring chamber, substantiating the structure and characteristics of the equipment for these studies, carrying out an experimental verification of the method and equipment on the real samples of materials for space technology. The possibility of using the calorimetric method for measuring the emission factor without vacuuming the volume of the measuring chamber, taking into account the heat transfer from the radiator to the surface of the sample through the air layer, is substantiated. The structure of the corresponding apparatus is recommended and the ratio of the geometric dimensions of the working chamber, in which the boundary distortion due to heat transfer through the air is insignificant, and the correction for conductive heat exchange can be easily calculated, is defined. The method of measurement and the description of the test stand on the basis of thermoelectric heat exchangers and absolute solar radiation receiver, which are intended to determine the absorption coefficient of solar radiation, are given. A brief description of the technology of coating Al + TiO2 layered structure and the measured values of emission factor and absorption coefficient of samples with such coating is given. It is shown that the ratio of the absorption coefficient of solar radiation to the emission factor for a two-layer coating is significantly lower than the similar value obtained for its individual components. It is established that by changing the ratio of thickness of layers of Al and TiO2 it is possible to reduce the ratio of coefficients to the value that provides an acceptable level of temperature of the surface of the spacecraft

Randomized Wilson loops, reduced models and the large D expansion

Reduced models are matrix integrals believed to be related to the large N limit of gauge theories. These integrals are known to simplify further when the number of matrices D (corresponding to the number of space-time dimensions in the gauge theory) becomes large. Even though this limit appears to be of little use for computing the standard rectangular Wilson loop (which always singles out two directions out of D), a meaningful large D limit can be defined for a randomized Wilson loop (in which all D directions contribute equally). In this article, a proof-of-concept demonstration of this approach is given for the simplest reduced model (the original Eguchi-Kawai model) and the simplest randomization of the Wilson loop (Brownian sum over random walks). The resulting averaged Wilson loop displays a scale behavior strongly reminiscent of the area law.Comment: 16 pages; v3: commentary further expanded, published versio

Additional Impact of Glucose Tolerance on Telomere Length in Persons With and Without Metabolic Syndrome in the Elderly Ukraine Population

Rationale: Association between different components of metabolic syndrome and the rate of age-related telomere shortening was reported repeatedly, although some findings are inconsistent across studies, suggesting the need for further research on the topic. In the present study, we examined relationships between different components of metabolic syndrome (MetS); glucose tolerance reflected in 2-h post-load plasma glucose (2hPG) levels and age on the leukocyte telomere length (LTL) in Ukraine population.Methods: The study was conducted on the 115 adult individuals residing in the Kyiv region (Ukraine). Among them, 79 were diagnosed with MetS according to the International Diabetes Federation definition. LTL were determined by a qPCR-based method. Multivariate logistic regression (MLR) and artificial neural networks (ANN) modeling were used for the analysis of the results. ROC-analysis was also performed to compare the predictively values of this models.Results: MetS was associated with a high (OR = 3.0 CI 1.3–6.7; p = 0.01) risk of having shorter telomeres that remained significant after adjusting for age, gender and 2hPG levels. Fasting plasma glucose (FPG) levels and other MetS components did not affect the magnitude of the relationship and did not reveal the independent influence of these factors. The level of 2hPG in turn, demonstrated a significant relationship (OR = 1.3 CI 1.0–1.6 per 1 mmol/l; p = 0.04) with LTL regardless of the presence of MetS. The non-linearity of the interactions between age, gender and 2hPG level was revealed by neural network modeling (AUC = 0.76 CI 0.68–0.84).Conclusion: Our study found that impaired glucose tolerance, but not FPG levels, affected the association between LTL and MetS, which may be also indicative for pathophysiological differences in these hyperglycemia categories. 2hPG levels can provide an opportunity for a more accurate diagnostics of MetS and for evaluating the rate of aging in patients with MetS. Further research, however, is needed to verify this assumption

Synurella odessana sp. n. (Crustacea, Amphipoda, Crangonyctidae), first report of a subterranean amphipod from the catacombs of Odessa and its zoogeographic importance

A new species from the catacombs of Odessa (South Ukraine), Synurella odessana sp. n. is described and its taxonomic affinity with congeners are discussed. This is the first record of the subterranean amphipod crustacean of the genus Synurella from an artificial biotope. The new species has numerous plesiomorphic features states allowing a more detailed evaluation of the taxonomy of the genus Synurella. The most remarkable feature of this new species is the presence of a “synurellid type” gnathopod 1 and a “crangonyctid type” gnathopod 2. Herein, we propose three groups in the genus Synurella distributed within the Volga-Black Sea basin: ambulans-group (epigean inhabitants of coastal lowlands, stygophiles), dershavini-group (hypogean or spring inhabitants of karstic regions, preadapted stygobionts), wachuschtii-group (minute inhabitants of interstitial waters, stygobionts). The dershavini-group occupies isolated taxonomic position among the synurellids. We suggest that the modern distribution of dershavini-group reflects the formation of ancient river basins in the region