111 research outputs found
Karboxyláty kovů v malířství - studium jejich vzniku, vlastnosti a chovaní.
No full textTitle: Metal carboxylates in paintings - the study of their formation, properties and behaviour Author: Mgr. Ruslan Barannikov Supervisor: RNDr. Jiří Plocek, Ph.D. Abstract: The formation of crystalline metal carboxylates in painted artworks presents a significant conservation challenge, as these compounds can compromise both the structural integrity and aesthetic appearance of cultural heritage objects. While lead carboxylates have been extensively characterized due to their prevalence in degraded areas containing lead-based pigments, crystalline mercury carboxylates, recently identified in portrait miniatures containing cinnabar (HgS), remain insufficiently investigated. My dissertation work aims to elucidate the formation mechanisms, structural characteristics, and thermal behaviour of mercury carboxylates, comparing them with lead analogues in the context of painting degradation to understand their potential synergistic effects. Through a systematic approach, simple and mixed mercury carboxylates of general formula Hg(C16)x(C18)2-x (where C16 stands for C15H31COO‾ and C18 je C17H35COO‾ while x = 0.0-2.0) were synthesized and characterized using complementary analytical techniques. The combination of X-ray powder diffraction (XRPD) and solid-state NMR spectroscopy (ssNMR) revealed that mercury...Název práce: Karboxyláty kovů v malířství - studium jejich vzniku, vlastnosti a chovaní Autor: Mgr. Ruslan Barannikov Vedoucí práce: RNDr. Jiří Plocek, Ph.D. Abstrakt: Tvorba krystalických karboxylátů kovů v malířských dílech představuje významný konzervátorský problém, neboť tyto sloučeniny ohrožují jak strukturální integritu, tak estetické kvality objektů kulturního dědictví. Zatímco olovnaté karboxyláty byly již důkladně charakterizovány vzhledem k jejich častému výskytu v degradovaných oblastech obsahujících olovnaté pigmenty, krystalické rtuťnaté karboxyláty, nedávno identifikované v portrétních miniaturách obsahujících rumělku (HgS), zůstávají nedostatečně prozkoumány. Má disertační práce si klade za cíl objasnit mechanismy vzniku, strukturní charakteristiky a tepelného chování rtuťnatých karboxylátů a porovnat je s jejich olovnatými analogy v kontextu degradace maleb pro pochopení jejich potenciálních synergických účinků. Systematickým přístupem byly syntetizovány a charakterizovány prosté i směsné rtuťnaté karboxyláty obecného vzorce Hg(C16)x(C18)2-x (kde C16 odpovídá C15H31COO‾ a C18 je C17H35COO‾ x = 0,0-2,0). Připravené látky byly charakterizovány pomocí vzájemně komplementárních analytických technik. Kombinace rentgenové práškové difrakce (XRPD) a NMR spektroskopie v pevné fázi (ssNMR) odhalily,...Department of Inorganic ChemistryKatedra anorganické chemiePřírodovědecká fakultaFaculty of Scienc
Editorial
No full textIn 2007, the world reached a pivotal moment in the ongoing process of urbanization, with the global urban population surpassing the rural population for the first time. Africa is the only continent where this process has not yet been completed. According to UN projections, it is expected to occur no earlier than the second third of the 21st century. Africa, however, is very diverse in this regard: in some countries, the majority of the population has long been urban, while in others, most of the population are still living in rural areas.“Anyone can define what a city is, except an urbanist”—this statement applies to Africa as well. The lack of consistent statistical criteria for defining cities and urban lifestyles makes it difficult to compare urban development indicators across countries. Nevertheless, using both national and international conceptual frameworks, the contributors to this special issue of R-Economy will examine the reasons behind the slow pace of urbanization in Africa and assess the role of the continent's cities in its socio-economic development.In his paper, “Luxury or Necessity? The Dynamics of Urbanization in Sub-Saharan Africa,” Suleiman Onimisi Mamman employs long time-series data from 1996 to 2022 to statistically assess the significance of various factors and conditions influencing urban development in sub-Saharan African countries. Drawing on E. Lee's theory, the author concludes that migration from rural areas to cities in Africa is primarily driven by individuals’ desire to access a wider range of services than those available in rural areas, including both social services (such as education and healthcare) and those related to the services sector (like housing and utilities).In their study “Digital education index in cities of Africa,” Victoria Akberdina and Maxim Vlasov assess the relationship between digital higher education as a key component of human capital and the urban and economic development of African countries. The findings did not support the initial hypothesis that the number of universities is directly related to the number of people with higher education and the proportion of digital technology users in cities. However, the study convincingly demonstrated that digital education serves as an effective mechanism for the formation and development of human capital.Ruslan Dmitriev, Stanislav Gorokhov, and Maksim Agafoshin, in their paper “From the “isolated states” to the central place system(s): water supply of the cities in modern Libya,” examine the development of the water supply system for urban settlements and agricultural enterprises in the country through the lens of J.-G. von Thünen's theory of the isolated state and W. Christaller's central place theory. The authors conclude that the “Great Man-Made River” system in Libya, in its current form, demonstrates a relatively high degree of spatial resilience. They argue that the decision made by M. Gaddafi's government to integrate previously separate water supply systems for urban areas was a sensible one.In the paper “Analyzing the District Performance Assessment Tool in Local Governments in Ghana,” John V. Mensah, Anthony E. Aikins, and David W. Essaw shift the focus from the population as the recipient of services to local government representatives as the providers. Through a qualitative analysis of survey data from the Central Region of Ghana, the authors show that enhancing the quality of services delivered at the local community level is achievable only through a comprehensive methodological approach.James O. Abugu, Fidelis U. Amahi, Johnson I. Okoh, Oyakhiromhe B. Agbadua, Emmanuel S. Udo, and Ifeanyi Onyemere in their paper “Income-level analysis of money demand stability in Sub-Saharan Africa using cross-sectional ARDL” use data from 1999 to 2023 to assess the economic stability of countries in this region. The authors conclude that on the regional level, there is a need for a unified monetary policy as well as for a single currency to stimulate economic growth and reduce regional disparities.In modern Western cities, disparities are largely mitigated—or, in theory, should be—creating unique “melting pots.” In contrast, the urban environment in Eastern cities does not inherently “free”[1] its residents. Those who migrate from rural areas often retain their positions within existing ethnic and clan structures at both local and regional levels, as well as significant aspects of rural life. This dynamic contributes to the phenomenon of false urbanization and other negative accompanying processes.In many respects, Eastern cities evolve according to principles that are not always comparable to those of Western cities. Given this context, the experiences of African countries in regulating urban processes are particularly noteworthy. The contibutors to this special issue invite interested colleagues to engage in this important discussion.[1] There is a medieval German proverb Stadtluft macht frei, meaning "The air of the city makes one free.
Formation of the settlement hierarchy: Zipf ’s law vs Central place theory
No full textThis study compares the possibilities and advantages of forming the settlement hierarchy according
to Zipf and according to Christaller, starting from the first stages of the settlement systems
development. The author found that the minimum number of hierarchy levels required
to start the formation of the Christaller distribution, bypassing the Zipf distribution stage, for
small values of the urbanization level was two: the first one, represented by one central place,
and the level of rural settlements. With virtually the same possibilities of forming a hierarchy
according to Zipf and according to Christaller at its initial stages in relation to the share of
urban population, the advantages of the latter give large values of the maximum share of each
central place in the population of the area it serves and lower costs of the system for the redistribution
of the population between the existing settlements and the settlements emerging
at a certain stage of evolution. At the same time, with an increase in the share of the urban
population, the correspondence of the real rank-size distribution of cities to the ideal one (according
to Zipf) decreases. The author established that the distribution according to Zipf and
according to Christaller is a kind of two “immiscible liquids”: if the first is based on stochastic
processes, then the second is based on non-random, even deterministic ones. The transition
of the settlement system from the distribution according to Zipf to the hierarchy according to
Christaller is a rather weak construct in the methodological and logical respect.This article was supported within state assignments of the Institute of Geography, Russian Academy
of Sciences (АААА-А19-119022190170-1 (FMGE-2019-0008)) and the Institute for African Studies,
Russian Academy of Sciences (I222021500170-8). The research methodology was developed within the state
assignment of the Institute of Geography, Russian Academy of Sciences; the calculations were performed
within the state assignment of the Institute for African Studies, Russian Academy of Sciences
Current problems of multimodal transport (in case of Russia - Czechia)
No full textThis diploma thesis relates to the issue of transportation goods from non-European countries to European countries. The main goal of this thesis is to determine the current problems of multimodal transportation from the Russian Federation to the Czech Republic. The secondary goal of this thesis is to identify the problems of development of multimodal transport in Russia via analysis of the current Russian transport system. The first part of this work describes the transport systems of the Czech Republic and the Republic of Kazakhstan and their trade relations with the Russian Federation. The second part of this work is focused on the transport system in Russia and its current problems. Author also considers what goals were not achieved and why.Tato diplomová práce je spojena s problematikou přemisťovaní zboží z mimoevropských zemí do zemí Evropy. Hlavním cílem této práce je určit aktuální problémy multimodální přepravy z Ruské federace do České republiky. Vedlejším cílem této práce je pomoci analýzy současného ruského dopravního systému determinovat problémy rozvoje multimodální přepravy v Rusku a navrhovat možné řešení těchto problémů. V první části této práce jsou popsány dopravní systémy Česka a Republiky Kazachstán a jejích obchodní vztahy s Ruskou federací. Druhá část této práce je zaměřena na dopravní systém v Rusku a jeho aktuální problémy. V rámci diplomové práce autor také uvažuje o tom, jaké cíle nebyly dosaženy a proč
Unemployment and labor market dynamics in Russia
No full textThe past 15 months have seen the beginning of structural change in Russia but a failure of the economy to stabilize. The balance sheet, conclude the authors suggests that a return to centralized control remain almost impossible, but the dencentralization that has occurred contain many undesirable features. In framing their analysis, the authors draw on aggregate data and firm-level data from the first-round results of a 1992 survey covering 41 firms in the Moscow region. The survey results suggest that the greater autonomy of firms has facilitated the exploitation of market power while failing to dampen the demand for easy credit from the budget or banking system. For the most part, demand has been satisfied, enabling firms to meet current wage claims and, to a lesser degree, sustain output levels. Buoyant nominal profits can be traced either to pricing behavior derived from market power or to transfers or subsidies channeled through the fiscal monetary system. This in turn has artificially sustained the revenue side of the government accounts. Official employment was no more than 1 percent of the labor force by the end of 1992, but evidence on the importance of marginal unemployment indicates that the underlying pass-through into open unemployment will be great. By the third quarter of 1992, this"augmented"unemployment rate approached 4 percent of the labor force. Even so, the authors observe non-trivial outflows from unemployment to jobs and in some regions to jobs in the private or collective sector. In Russia, outflows to state sector jobs dominate. Survey evidence shows considerable turnover in the state sector and resilient hiring. Much of the churning in labor markets seems to be through voluntary separations and job transitions. Net changes to employment have been limited, and have involved mostly ancillary or clerical staff. The authors discern a core or membership rule dominating Russian firms'decisions which it would be dangerous to assume will be maintained. They interpret it as a holding strategy in a complex game the firms have been playing with government. Lack of a credible reform program has weakened any impulse toward large-scale restructuring of firms. Wages have been more volatile and have regional dispersion, but the authors predict no large consistent shift in relative wages. Rather the wage path has probably been governed by current streams and additional transfers, and then set consistent with the stable employment rule. The path of wages over 1992 is clearly associated with changes in Russia's monetary and fiscal stance and allied institutional features.Environmental Economics&Policies,Economic Theory&Research,Banks&Banking Reform,Markets and Market Access,Access to Markets
Bafilomycin A1 activates respiration of neuronal cells via uncoupling associated with flickering depolarization of mitochondria
No full textBafilomycin A1 (Baf) induces an elevation of cytosolic Ca2+ and acidification in neuronal cells via inhibition of the V-ATPase. Also, Baf uncouples mitochondria in differentiated PC12 ((d)PC12), dSH-SY5Y cells and cerebellar granule neurons, and markedly elevates their respiration. This respiratory response in (d)PC12 is accompanied by morphological changes in the mitochondria and decreases the mitochondrial pH, Ca2+ and Delta Im. The response to Baf is regulated by cytosolic Ca2+ fluxes from the endoplasmic reticulum. Inhibition of permeability transition pore opening increases the depolarizing effect of Baf on the Delta Im. Baf induces stochastic flickering of the Delta Im with a period of 20 +/- A 10 s. Under conditions of suppressed ATP production by glycolysis, oxidative phosphorylation impaired by Baf does not provide cells with sufficient ATP levels. Cells treated with Baf become more susceptible to excitation with KCl. Such mitochondrial uncoupling may play a role in a number of (patho)physiological conditions induced by Baf
Tres extraordinarios conciertos a cargo de la Orquesta Filarmónica de Leningrado (URSS)
No full textPrograma dels tres concerts que l'Orquestra Filharmònica de Leningrad van fer al Liceu durant la temporada 1971-1972. Durant la primera jornada van interpretar l'obertura de "Ruslan i Lyudmila" de M. Glinka, la "Simfonia núm. 5 op. 47" de D. Shostakovich i la "Simfonia núm. 5 en mi menor, op. 64" de P. I. Txaikovski. El concert va estar dirigit per A. Jansons. Durant la segona jornada van interpretar la "Simfonia Clàssica en re major, Op. 25" de S. Prokofiev, el "Concert núm. 3 per a piano i orquestra, Op. 30" de S. Rakhmaninov i la "Simfonia núm. 4 en fa menor, Op. 36" de P. I. Txaikovski. Va estar dirigit per A. Dmitriev i va comptar amb el pianista A. Slobodyanik. Finalment, a l'últim concert es va sentir la "Suite núm. 2 de Romeo i Julieta, Op. 64" de S. Prokofiev, el "Concert en re major per a violí i orquestra, Op. 35" de P. I. Txaikovski, i la "Simfonia núm. 6 en si menor, Op. 75 - Patètica" de P. I. Txaikovski. La direcció va anar a càrrec d'A. Jansons i el solista va ser V. VaimanOrquestra Filharmònica de Leningrad, dirigida per A. Jansons i A. Dmitriev, solistes Alexander Slobodyanic (piano) i Mikhail Vaiman (violí
Andrei Siniavskii. A hero of his time?
No full textThis thesis is an artistic biography of Andrei Siniavskii (1925-1997) as a
writer in and of his time, showing how this subtle and complex author found his
way in a society polarised into heroes and villains, patriots and traitors; how he
progresses from identification with the value system and ideology of his time to
reaction against it, his dissidence expressed in literary terms.
Beyond this, I hope to show how he moves to a new conception of the writer
in the fusion of his creative and critical selves that is dominated neither by the
voice of the collective ‘we’, nor by the voice of the individual ‘I’ but which
leaves space in the text for engagement by the reader. Individual readers,
passing manuscripts from hand to hand or reciting texts orally had assured the
continuity of the Russian literary tradition during the long bleak years when
literature seemed to mark time under the strictures of Soviet ideology and
Socialist Realist aesthetics. Siniavskii’s work is motivated by the passionate
belief that the way forward for Russian literature lay in this same spark
generated between individual reader and text.
My thesis is organised chronologically and is based on a close reading of
Siniavskii’s work. It explores the way his art does not simply reflect the
circumstances of his life and times but is actively shaped by an intricate
commerce between the two. I intend to show how Siniavskii’s distancing
himself, first ideologically then physically, from the Soviet system is
counterbalanced by his creative reintegration with Russia through literature
Direct sale and its importance in retailing
No full textThe main goal of this Bachelor's Thesis is to find out what are the main reasons for a customer to buy a product, and what makes difference in making decision for a client. "Navigate, selling the way people like to buy", is the book which will be used for theoretical part, from author Dustin Hillis. Dustin Hillis is a very successful sales person and divides customers into 4 different groups based on style they like to buy products. The same method used for example Lee McCroskey in his seminar "Becoming a Chameleon". I will use those 4 types of customers in first part to compare theory with my experience from direct sales. For practical use I have chosen Southwestern Company. I will use mainly my own experience and notes that I collected last 3 years. I personally sold products to 850 customers in 240 days. In last part of this thesis I will analyze how useful is theoretical knowledge in particular sales situations and also types of customers
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