SOME ASPECTS OF THE REGIONAL COOPERATION IN THE BALKANS

Since the beginning of the 21st century, the political role of the state borders in the Balkans has changed. Gradually they began to transform from barriers into zones of bilateral and multilateral cooperation. The common European integration includes the creation and development of Euro-regions. Within the context of reorganization of the new European space, geopolitical importance of South-East Europe has significantly upgraded. This fact reflects on the interests of the international community in security and development of this region. Despite that the Balkans constitute an indispensable part of the European continent, their incorporation into the new European architecture has been particularly difficult and problematic. They emerge as the most volatile and least integrated European region. There are significant variations among the countries concerning their territory, number of population, as well as the rate of the economic changes. The main forms of regional cooperation should be concentrated on the domains of transport, energy and communication infrastructure, trade and economic cooperation, environment and security. From this point of view, the economic growth and increase of living standard are the most important problems for all Balkan countries

Dynamic competition with customer recognition and switching costs: theory and application

This dissertation aims to contribute to our understanding of dynamic interaction in duopoly markets. Chapter 1 motivates the study and offers a brief overview of the results. In Chapter 2 I study the dynamic equilibrium of a market characterized by repeat purchases. Such markets exhibit two common features: customer recognition, which allows firms to price discriminate on the basis of purchase history, and consumer switching costs. Both features have implications for the competitiveness of the market and consumer welfare but are rarely studied together. I employ a dynamic framework to model a market with customer recognition and switching costs. In contrast to earlier studies of dynamic competition with switching costs, these costs are explicitly incorporated in the demand functions. Two sets of market equilibria are characterized depending on the size of the switching cost. For all values of the switching cost, customer recognition gives rise to a bargain-then-ripoff pattern in prices and switching costs amplify the loyalty price premium. When switching costs are low, there is incomplete customer lock-in in steady state, firm profits increase in the magnitude of the switching cost and introductory offers do not fall below cost. When switching costs are high, there is complete customer lock-in in steady state, firm profits are independent of switching costs and introductory prices may fall below cost. Under incomplete lock-in and bilateral poaching, switching costs do not affect the speed of convergence to steady state; under complete customer lock-in and no poaching from either firm, convergence to steady state occurs in just one period. The model also suggests that imperfect customer recognition leads to lower profits relative to both uniform pricing and perfect customer recognition. In Chapter 3 I use the market framework developed in Chapter 2 to examine the perception that imperfect competition hinders information sharing among rivals in games of random matching. In contrast to previous studies of information sharing, I propose a new channel through which competition may deter information sharing. This approach reveals a key role for firm liquidity by showing that information sharing among rivals is more likely to arise in markets populated by more liquid firms. Employing a dynamic duopoly framework, in which competition intensity varies with the degree of product differentiation, consumer switching costs and consumer patience, I show that more intense market competition can weaken the disincentives associated with disclosing information to a rival. I test the model's predictions using firm-level data on the information-sharing practices of agricultural traders in Madagascar. As predicted by the model, traders operating in liquid markets are shown to be more likely to share information about delinquent customers. This result is robust to the use of two alternative measures of liquidity, of which one is credibly exogenous, and two alternative ways of defining market liquidity. Furthermore, traders who report more intense competition in their market are found to be significantly more likely to share information

Classification of Chenopodium Genus Populations and Species Based on Continuous and Categorical Variables

2000 Mathematics Subject Classification: 62P10, 62H30The estimation of statistical distance between populations arises in many multivariate analysis techniques. Whereas distance measures for continuous data are well developed, those for mixed discrete and continuous data are less so because of the lack of a standard model for such data. Such mixture of variables arise frequently in the field of medicine, biometry, psychology, econometrics and only comparatively few models have been developed for evaluating distance between populations. The subject of our study were data in the field of botany. The aim of the presented investigation was to apply methods for analysis of dissimilarity between 44 populations of 13 species of Ghenopodium genus,presented by 15 variables - 10 continuous and 5 categorical. The previously developed by another authors distance measures between populations presented by mixed attributes turned out not appropriate for the available data of Chenopodium genus. F or that reason a specific distance measures were applied. The matrices with distances between populations and species were used as input for Hierarchical Cluster Analysis to explore the taxonomic structure of the Chenopodium genus

Bassia hirsuta (L.)’nın Bulgaristan populasyonlarındaki karyolojik ve morfolojik varyasyonlar

This study was performed to determine karyological and morphological variability within and between populations of Bassia hirsuta in Bulgaria and to reveal their ecological preferences and detailed morphological characteristics. The studied Bulgarian B. hirsuta populations have diploid chromosome number 2n=18. The interpopulation variability which could be due to differences in ecological conditions is dominant. Vegetative traits are more variable than generative ones. The least variable are those that characterize the seed and could be used as highest value traits. The data given in the present study are supplementary to the data given about the species in Flora of the People’s Republic of Bulgaria and can be used both for correct identifications of the specimens and for getting familiar with species characteristicsBassia hirsuta’nın Bulgaristan’daki populasyonlarındaki karyolojik ve morfolojik varyasyonu belirlemek ve populasyonların ekolojik tercihlerini ve detaylı morfolojik karakterlerini ortaya koymak amacıyla yapılmıştır. Çalışmada kullanılan B. hirsuta’nın Bulgaristan populasyonlarındaki diploid kromozom sayısı 2n=18’dir. Ekolojik şartlara bağlı olabilen populasyonlar arası varyasyon baskın durumdadır. Vejetatif özellikler, generatif özelliklere göre çok daha fazla varyasyon göstermektedir. En az varyasyon gösteren özellikler tohumla ilgili olanlardır ve önem dereceleri yüksek özellikler olarak kullanılabilirler. Bu çalışmada elde edilen bulgular, B. hirsute ile ilgili olarak “Flora of the People’s Republic of Bulgaria”da verilen bilgileri tamamlayıcı niteliktedir ve hem örneklerin doğru bir şekilde teşhis edilmeleri hem de türün özelliklerinin daha yakından tanınması amacıyla kullanılabili

Bed bug cytogenetics: karyotype, sex chromosome system, FISH mapping of 18S rDNA, and male meiosis in Cimex lectularius Linnaeus, 1758 (Heteroptera: Cimicidae)

Bugs (Insecta: Heteroptera) are frequently used as examples of unusual cytogenetic characters, and the family Cimicidae is one of most interest in this respect. We have performed a cytogenetic study of the common bed bug Cimex lectularius Linnaeus, 1758 using both classical (Schiff-Giemsa and AgNO3-staining) and molecular cytogenetic techniques (base-specific DAPI/CMA3 fluorochromes and FISH with an 18S rDNA probe). Males originated from a wild population of C. lectularius were found to have 2n = 26 + X1X2Y, holokinetic chromosomes, 18S rRNA genes located on the X1 and Y chromosomes; achiasmate male meiosis of a collochore type; MI and MII plates nonradial and radial respectively

Abiotic methane synthesis and serpentinization in olivine-hosted fluid inclusions

© The Author(s), 2019. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Proceedings of the National Academy of Sciences.of the United States of America 116(36), (2019): 17666-17672. doi:10.1073/pnas.1907871116.The conditions of methane (CH4) formation in olivine-hosted secondary fluid inclusions and their prevalence in peridotite and gabbroic rocks from a wide range of geological settings were assessed using confocal Raman spectroscopy, optical and scanning electron microscopy, electron microprobe analysis, and thermodynamic modeling. Detailed examination of 160 samples from ultraslow- to fast-spreading midocean ridges, subduction zones, and ophiolites revealed that hydrogen (H2) and CH4 formation linked to serpentinization within olivine-hosted secondary fluid inclusions is a widespread process. Fluid inclusion contents are dominated by serpentine, brucite, and magnetite, as well as CH4(g) and H2(g) in varying proportions, consistent with serpentinization under strongly reducing, closed-system conditions. Thermodynamic constraints indicate that aqueous fluids entering the upper mantle or lower oceanic crust are trapped in olivine as secondary fluid inclusions at temperatures higher than ∼400 °C. When temperatures decrease below ∼340 °C, serpentinization of olivine lining the walls of the fluid inclusions leads to a near-quantitative consumption of trapped liquid H2O. The generation of molecular H2 through precipitation of Fe(III)-rich daughter minerals results in conditions that are conducive to the reduction of inorganic carbon and the formation of CH4. Once formed, CH4(g) and H2(g) can be stored over geological timescales until extracted by dissolution or fracturing of the olivine host. Fluid inclusions represent a widespread and significant source of abiotic CH4 and H2 in submarine and subaerial vent systems on Earth, and possibly elsewhere in the solar system.We are indebted to J. Eckert for his support with FE-EMPA; to K. Aquinho and E. Codillo for providing samples from Zambales; to K. Aquinho for Raman analysis of some of the samples from Zambales and Mt. Dent; to H. Dick for providing access to his thin section collection; to the curators of the IODP core repositories for providing access to Ocean Drilling Program (ODP) and Integrated Ocean Drilling Program (IODP) samples; and to the captains and crews of the many cruises without whom the collection of these samples would not have been possible. Reviews by Peter Kelemen and an anonymous referee greatly improved this manuscript. This study is supported with funds provided by the National Science Foundation (NSF-OCE Award 1634032 to F.K. and J.S.S.).2020-02-1

Refractory epilepsy - New treatment technologies. chance and future for the children

Епилепсията е сборно клинично понятие, което включва различни хронични заболявания на главния мозък, които се характеризират с повтарящи се пристъпи, възникващи на базата на свръхвъзбуда на определени групи неврони. Клинично се проявяват с различни преходни сетивни, двигателни, автономни, поведенчески или психически симптоми. Думата „епилепсия` идва от гръцки език „επιληψία` и означава „сграбчвам`, „нападам`, „атакувам`. Болестта е известна още като morbus sacer (от лат. свещена болест). Позната е на човечеството от хиляди години. Първите признаци могат да се появят във всяка възраст, като две възрастови групи са най-уязвими детската и след 70 години. Повече от 50% от епилепсиите започват до 10-годишна възраст, a 75% - до 20-годишна възраст. Според своята причина епилепсията се разделя на две основни груп- симптоматична епилепсия, с начало в зрялата възраст, и идиопатична (с неясна причина), която е по-характерна за детството. Диагностичният процес при болните с епилепсия преминавпрез няколко последователни етапа: характеризиране и определяне вида на епилептичния пристъп; класифициране на епилептичния синдром; изясняване на етиологията на заболяването. Основните методи на лечение са чрез антиепилептични медикаменти, хирургично лечение и кетогенна диета, като те често са взаимодопълващи се. Има обаче пациенти, при които болестта не се повлиява от медикаментите, т.нар. фармакорезистентна епилепсия. Най-честото усложнение при пациенти с тежка фарма - корезистентна епилепсия, е когнитивният дефицит, който настъпва постепенно в резултат на повтарящите се епилептични пристъпи - броят на които може да достигне до 100 на ден. С развитието на медицината днес хирургичното лечение на фармакорезистентната епилепсия приема нов облик благодарение на новите медицински технологии. Голямата медицинска и социална значимост на фармакорезистентната епилепсия се определя не само от широкото разпространение на болестта, но и поради това, че засяга предимно деца, хора в млада възраст.Epilepsy is an umbrella clinical term which encompasses various chronic conditions of the cerebrum, characterized by recurring seizures resulting from overstimulation of certain groups of neurons. Clinically, these disorders manifest in various transitory sensory, motor, autonomous, behavioural or mental symptoms. The word epilepsy comes from the Greek word `επιληψία` , meaning `to seize`, `to assault`, `to attack`. The disease is also known as morbus sacer (Latin for sacred disease). It has been known to humanity for thousands of years. The first symptoms can manifest in any age, with two age groups being most vulnerable - children and people over 70. More than 50% of the cases of epilepsy start before the age of 10 and 75% before the age of 20. Based on the cause, epilepsy is divided into two main groups - symptomatic epilepsy which starts in adult age and idiopathic (with unknown cause) epilepsy that is more common in adolescence. The diagnostic process in the case of people suffering from epilepsy involves several successive stages: characterizing and establishing the type of epileptic seizure; classifying the epilepsy syndrome; clarifying the etiology of the disease. The main treatment methods involve anti-epileptic drugs, surgery and ketogenic diet and these methods often complement each other. But in some patients, the disease is not affected by the drugs, this is the so-called refractory epilepsy. The most common complication in patients with severe refractory epilepsy is the cognitive deficit which sets in gradually as a result of the recurring epileptic seizures which can become as many as 100 per day. Today, with the development of medical science, surgical treatment of refractory epilepsy is now changing thanks to the new medical technologies. The big medical and social importance of refractory epilepsy is due not only to the wide spread of the disease but also because it affects mostly children and adolescents

Carbon and mineral transformations in seafloor serpentinization systems

Submitted in partial fulfillment of the requirements for the degree of Doctor of Philosophy at the Massachusetts Institute of Technology and the Woods Hole Oceanographic Institution February 2018This thesis examines abiotic processes controlling the transformation and distribution of carbon compounds in seafloor hydrothermal systems hosted in ultramafic rock. These processes have a direct impact on carbon budgets in the oceanic lithosphere and on the sustenance of microorganisms inhabiting hydrothermal vent ecosystems. Where mantle peridotite interacts with carbon-bearing aqueous fluids in the subseafloor, dissolved inorganic carbon can precipitate as carbonate minerals or undergo reduction by H2(aq) to form reduced carbon species. In Chapters 2 and 3, I conduct laboratory experiments to assess the relative extents of carbonate formation and CO2 reduction during alteration of peridotite by CO2(aq)-rich fluids. Results from these experiments reveal that formation of carbonate minerals is favorable on laboratory timescales, even at high H2(aq) concentrations generated by serpentinization reactions. Although CO2(aq) attains rapid metastable equilibrium with formate, formation of thermodynamically stable CH4(aq) is kinetically limited on timescales relevant for active fluid circulation in the subseafloor. It has been proposed that CH4 and potentially longer-chain hydrocarbons may be sourced, instead, from fluid inclusions hosted in plutonic and mantle rocks. Chapter 4 analyzes CH4-rich fluid inclusions in olivine-rich basement rocks from the Von Damm hydrothermal field and the Zambales ophiolite to better understand the origin of abiotic hydrocarbons in ultramaficinfluenced hydrothermal systems. Comparisons of hydrocarbon abundances and stable isotopic compositions in fluid inclusions and associated vent fluids suggest that fluid inclusions may provide a significant contribution of abiotic hydrocarbons to both submarine and continental serpentinization systems.This thesis research was funded by the National Science foundation through grants OCE- 1427274 and OCE-1634032. Louise Von Damm generously contributed financial support for research conducted in Chapter 4