Mean-Variance Portfolio Selection with Reference Dependent Preferences

We study S-shaped utility maximization for the standard portfolio selection problem with one risky and one risk-free asset. We derive a mean-variance criterium of choice, which preserves reference dependence and the reflection effect. Subsequently, we study diversification possibilities and obtain the demand for the risky asset. We close the paper with an alternative interpretation of the criterium in terms of target-based decision making.portfolio selection, S-shaped utility, prospect theory, reference point, mean-variance analysis, demand for the risky asset, target-based decisions.

Asset return and wealth dynamics with reference dependent preferences and heterogeneous beliefs

We study a model of a financial market populated with heterogenous agents whose preferences exhibit dependence on some reference level of wealth. Investment decisions of the agents are myopic and are based upon the demand for the risky asset derived from an S-shaped utility maximization. The specific demand form allows to model both heterogeneity of the system relative to the reference points of the agents and heterogeneity with respect to their beliefs about the future asset return. We analyze the impact of the former layer of heterogeneity on the asset return and wealth dynamics.

Asset Price Dynamics with Local Interactions under Heterogeneous Beliefs

This paper investigates the effect of network structure on the asset price dynamics. We propose a simple present value discounted asset pricing model with heterogeneous agents. Every period the agents choose a predictor of the future price on the basis of past performance of their own and alternative strategies and form their demands for a risky asset. The information about the performance of an alternative strategy is available only locally from the directly connected agents. Using the rewiring procedure we produce four types of commonly considered networks: a fully connected network, a regular lattice, a small world, and a random network. The results show that the network structure influences asset price dynamics in terms of the region of stability and volatility. This is mostly due to the different speed of information transmission in the different networks.

Економічна інтеграція країн АСЕАН: досягнення, проблеми, перспективи

У здійсненому дослідженні наголошується на постійно триваючій у світовій господарській системі безкомпромісній боротьбі за переділ сфер впливу із застосуванням політичних, ідеологічних, психологічних, військових, економічних, інформаційних та інших методів. Розглянуто основи міжнародної економічної інтеграції у рамках СОТ та зміни, що відбуваються під впливом кризи неоліберальної моделі глобалізації. Розкрито особливості розробки і реалізації регіональних торгових угод для здійснення політики вибіркової лібералізації торгівлі на противагу дії протекціоністських сил у міжнародній торгівлі, що виступає певним гальмом у розвитку міжнародних економічних відносин. Розвиток інтеграційних процесів у світовій торгівлі розглядається на прикладі Асоціації держав Південно-Східної Азії – АСЕАН. Наведено основні мотиви та головні цілі країн при намірі заснування АСЕАН (прискорення економічного, соціального і культурного розвитку країн-учасниць на основі співпраці і взаємодопомоги; підтримка і розширення взаємовигідного співробітництва із загальними та регіональними міжнародними організаціями тощо). Здійснена загальна характеристика соціально-економічного розвитку “десятки»” країн АСЕАН за низкою критеріїв. Виявлено тенденції становлення та розвитку економічних відносин між окремими країнами зазначеної регіональної міжурядової організації, а також в цілому в АСЕАН в рамках створеної зони вільної торгівлі. Визначено особливості співробітництва АСЕАН з основними торговельно-економічними партнерами і міжнародними економічними організаціями. Досліджуються напрями зміцнення Співтовариства АСЕАН – від торгівлі товарами і послугами до вирішення соціальних та екологічних проблем. Здійснено оцінку стану та перспектив поглиблення торговельно-економічних відносин між країнами АСЕАН і Україною. Наголошується на можливості та необхідності розширювати взаємовигідні економічні відносини як в агропромисловій сфері, так і в галузях машинобудування, у військово-технічній сфері, залученні інвестицій, реалізації освітніх програм.The research carried out emphasizes continuously in the global economic system an uncompromising struggle for redistribution of spheres of influence with the use of political, ideological, psychological, military, economic, information and other methods. The basis of international economic integration within the framework of the WTO and changes taking place under the influence of the crisis of the neoliberal model of globalization are considered. The features of the development and implementation of regional trade agreements for the implementation of the policy of selective trade liberalization, in contrast to the effect of protectionist forces in international trade, are being identified, which is a certain obstacle to the development of international economic relations. The development of integration processes in world trade is considered by the Association of Southeast Asian Nations – ASEAN. The main motives and main goals of the countries are set out with the intention of establishing ASEAN (accelerating the economic, social and cultural development of the participating countries on th e basis of cooperation and mutual assistance, support and expansion of mutually beneficial cooperation with general and regional international organizations, etc.). A general description of the socio-economic development of the dozens of ASEAN countries has been carried out on a number of criteria. The tendencies of formation and development of economic relations between the individual countries of the mentioned regional intergovernmental organization, as well as in the whole of ASEAN within the framework of the created free trade zone, were revealed. The features of ASEAN cooperation with major trade and economic partners and international economic organizations are determined. Areas of the strengthening of the ASEAN Community – from trade in goods and services to solving social and environmental problems – are being explored. The assessment of the state and prospects of deepening of trade and economic relations between the countries of ASEAN and Ukraine is carried out. It emphasizes the possibilities and necessity to expand mutually beneficial economic relations both in the agro-industrial sphere and in the branches of machine-building, military-technical sphere, investment attraction and implementation of educational programs

Strategic course of Ukraine for european integration: achievements and unsolved problems

The sources, state and prospects of the strategic course chosen by Ukraine for integration into the European Union are considered. The analysis of disintegration processes associated with the collapse of the Soviet Union and the rupture of traditional economic relations of Ukraine with the CIS countries and the EAEU is presented. The results of the implementation of the economic part of the Association Agreement between Ukraine and the EU are evaluated. Attention is drawn to the need to further deepen trade relations with the EU, simplify customs procedures, strengthen environmental measures, digitalize the economy and introduce an “industrial visa-free regime”. In the foreign economic policy of the state, it is recommended to draw lessons from Brexit with an orientation on the use of the principle of cyclicality in the development of socio-economic systems

Asset price dynamics with small world interactions under hetereogeneous beliefs

We propose a simple model of a financial market populated with heterogeneous agents. The market represents a network with nodes symbolizing the agents and edges standing for connections between them, thus, embodying local interactions in the market. By local interactions we mean any kind of interplay between the decisions of the agents unaffected by the market mechanism and unrelated to the physical distance between the agents. Using the rewiring procedure we restructure a network from regular lattice to random graph by varying the probability of the agents to switch from one trading strategy to another. We study how the network structure influences the asset price dynamics. The results show that for some intermediate values of the probability to switch, corresponding to a small world network, the price dynamics become reminiscent to the real. While for the boundary values of the probability the dynamics lacks some typical features of the real financial markets.local interactions, networks, small world, heterogeneous beliefs, price dynamics, bifurcations, chaos

Indicators of Energy Metabolism in Patients during the Early Recovery Period of Ischemic Stroke under the Influence of Complex Therapy Using Neuroprotectors and Vasoactive Drugs

Ischemic stroke remains one of the most urgent health and social problems as well as the leading cause of disability in neurological patients.The objective of the research was to study and evaluate the efficiency of complex therapy using choline alphoscerate and vincamine in patients during the early recovery period of ischemic stroke considering the processes of energy metabolism.Materials and methods. The study involved 66 patients in the early recovery period of primary hemispheric ischemic stroke being randomized into 2 groups. Group 1 received basic therapy for secondary prevention of stroke. Patients of Group 2 received choline alphoscerate and vincamine for 2 months in addition to basic therapy. The evaluation of neurological deficit and functional status of patients was carried out using the NIH Stroke Scale, the Scandinavian stroke scale (SSS) and the Barthel Index; the concentration of lactic and pyruvic acid in serum was determined.Results. After treatment the NIH Stroke Scale score decreased significantly by 17.7%, the SSS score increased by 22.7% and the Barthel Index increased by 16.2%  in Group 2 (p<0.05). There was detected a moderate correlation (r=0.34; p=0.031) between the lactate level and the NIH Stroke Scale score as well as a moderate inverse correlation between the lactate level and the SSS score (r=-0.42; p=0.032) one month after stroke. In addition, 3 months  after stroke increased initial lactate level correlated inversely with the SSS score (r=-0.41; p=0.036) and the lactate-to-pyruvate ratio correlated with the SSS score (r=-0.47; p=0.039) and the Barthel Index (r=-0.29; p=0.046).Conclusions. Early recovery period of ischemic stroke is characterized by the disorders of energy metabolism, signs of activation of anaerobic glycolysis with increased serum levels of lactate and lactate-to-pyruvate ratio which may be predictors of unfavourable functional outcome. Complex therapy using choline alphoscerate and vincamine can contribute to the normalization of energy metabolism as well as to the reduction in clinical manifestations of neurological disorders

MicroRNAs Regulating Cytoskeleton Dynamics, Endocytosis, and Cell Motility-A Link Between Neurodegeneration and Cancer?

The cytoskeleton is one of the most mobile and complex cell structures. It is involved in cellular transport, cell division, cell shape formation and adaptation in response to extra- and intracellular stimuli, endo- and exocytosis, migration, and invasion. These processes are crucial for normal cellular physiology and are affected in several pathological processes, including neurodegenerative diseases, and cancer. Some proteins, participating in clathrin-mediated endocytosis (CME), play an important role in actin cytoskeleton reorganization, and formation of invadopodia in cancer cells and are also deregulated in neurodegenerative disorders. However, there is still limited information about the factors contributing to the regulation of their expression. MicroRNAs are potent negative regulators of gene expression mediating crosstalk between different cellular pathways in cellular homeostasis and stress responses. These molecules regulate numerous genes involved in neuronal differentiation, plasticity, and degeneration. Growing evidence suggests the role of microRNAs in the regulation of endocytosis, cell motility, and invasiveness. By modulating the levels of such microRNAs, it may be possible to interfere with CME or other processes to normalize their function. In malignancy, the role of microRNAs is undoubtful, and therefore changing their levels can attenuate the carcinogenic process. Here we review the current advances in our understanding of microRNAs regulating actin cytoskeleton dynamics, CME and cell motility with a special focus on neurodegenerative diseases, and cancer. We investigate whether current literature provides an evidence that microRNA-mediated regulation of essential cellular processes, such as CME and cell motility, is conserved in neurons, and cancer cells. We argue that more research effort should be addressed to study the neuron-specific functions on microRNAs. Disease-associated microRNAs affecting essential cellular processes deserve special attention both from the view of fundamental science and as future neurorestorative or anti-cancer therapies.Peer reviewe