Research of Environmental Problems in Industrial Cities

The current state of the environmental situation requires attention, particularly in the Dnipropetrovsk region. The concentration of industrial facilities in the region exceeds the average for Ukraine more than twice

How to improve computer performance

Nowadays a large number of people use computers for different purposes such as games, work, listening to music, watching videos, making presentations etc. However, while operating a computer, most users often have to cope with the low performance of their machines. And as some people do not know how to optimize the computers, they buy a new one, even more expensive, thinking that it will solve the problem. In this case basic knowledge of computer optimization can save both time and money

Analyzing the persistence of currency substitution using a ratchet variable: The Turkish case

Although previous studies on currency substitution in Turkey confirm the existence of currency substitution, these works ignore whether this process reached an irreversible stage or not. This paper analyzes the persistence of currency substitution in Turkey through inclusion of a ratchet variable, the past peak value of the currency substitution. Results using an autoregressive distributed lag (ARDL) approach suggest that currency substitution during 1990-93 is not persistent enough to be irreversible. During 1995-99, even though currency substitution in the narrow sense is persistent, currency substitution in the broader sense is not irreversible. Therefore, there is still room for effective monetary policy

Архітектурний компонент православних сакральних пам’ятників

The article raised some questions about the study architectural component in shaping the artistic monuments sacred "small" architecture Orthodox gravestones in Ukraine. The attention paid to the most common forms of tombstones, namely in the form of slabs, stone crosses, obelisks, columns, lectern, the tree of life, Kurgan Calvary, etc., which are considered an integral architectural components tombstone.В статье поставлен ряд вопросов к исследованию архитектурного компонента в художественном формообразовании памятников сакральной «малой» архитектуры православных надгробий в Украине. Внимание уделено наиболее распространенным формам надгробий, а именно: в виде плиты, каменного креста, обелиска, колонны, аналоя, дерева жизни, кургана-голгофы и тому подобное, которые считаются архитектурными компонентами целостного надгробного памятника.У статі поставлено  питаня дослідження о компоненту у  формотворенні архітектури православних надгробків в Україні. Увагу приділено найбільш поширеним формам надгробків, а саме: у вигляді плити, кам’яного хреста, обеліска, колони, аналоя, дерева життя, кургана-голгофи тощо, які вважаються архітектурними компонентами цілісного надгробного пам’ятника

Investigation of initiation of gigantic jets connecting thunderclouds to the ionosphere

The initiation of giant electrical discharges called as "gigantic jets" connecting thunderclouds to the ionosphere is investigated by numerical simulation method in this paper. Using similarity relations, the triggering conditions of streamer formation in laboratory situations are extended to form a criterion of initiation of gigantic jets. The energy source causing a gigantic jet is considered due to the quasi-electrostatic field generated by thunderclouds. The electron dynamics from ionization threshold to streamer initiation are simulated by the Monte Carlo technique. It is found that gigantic jets are initiated at a height of ~18-24 km. This is in agreement with the observations. The method presented in this paper could be also applied to the analysis of the initiation of other discharges such as blue jets and red sprites.Comment: 12th International Congress on Plasma Physics, 25-29 October 2004, Nice (France

A partition functional and thermodynamic properties of the infinite-dimensional Hubbard model

An approximate partition functional is derived for the infinite-dimensional Hubbard model. This functional naturally includes the exact solution of the Falicov-Kimball model as a special case, and is exact in the uncorrelated and atomic limits. It explicitly keeps spin-symmetry. For the case of the Lorentzian density of states, we find that the Luttinger theorem is satisfied at zero temperature. The susceptibility crosses over smoothly from that expected for an uncorrelated state with antiferromagnetic fluctuations at high temperature to a correlated state at low temperature via a Kondo-type anomaly at a characteristic temperature $T^\star$. We attribute this anomaly to the appearance of the Hubbard pseudo-gap. The specific heat also shows a peak near $T^\star$. The resistivity goes to zero at zero temperature, in contrast to other approximations, rises sharply around $T^\star$ and has a rough linear temperature dependence above $T^\star$.Comment: 18 pages, 6 figures upon request, latex, (to appear in Phys. Rev. B

Pharmacological screening of some traditionally-used antimalarial plants from the Democratic Republic of Congo compared to their ecological taxonomic equivalence in Madagascar

Hydro-alcoholic extracts of some plant species growing in two different geographical regions (Democratic Republic of Congo and Madagascar) were evaluated for their inhibitory effects on two malaria parasites strains (P. falciparum FcM29 & P. yoelii subsp nigeriensis) and cytotoxicity towards leukaemia P- 388 cell lines. Results indicate that, the antiplasmodial activity of tested plants varied geographically. Plants growing in continent ecosystem are more active in vitro while their ecological equivalence inhabiting island ecosystems are more active in vivo. It would be conclude that, the development of phytomedicines from plants of different geographical regions selected by bioguided fractionation would allow the populations to reduce the health care cost. The chemotaxonomic approach has also permitted us to detect moderate antiplasmodial activities in Neobegua mahafaliensis, a plant species not previously reported as antimalarial in the traditional medicine knowlegde of Madagascar. The use of a pharmacological property such as the antimalarial activity, in this study, in order to establish genetic filiations between the plants species is an original approach. Keywords: Malaria, medicinal plants, cytotoxicity, Dem. Rep. of Congo, Madagascar, phenotypic marker, genetic filiatio

The limits of social class in explaining ethnic gaps in educational attainment

This paper reports an analysis of the educational attainment and progress between age 11 and age 14 of over 14,500 students from the nationally representative Longitudinal Study of Young People in England (LSYPE). The mean attainment gap in national tests at age 14 between White British and several ethnic minority groups were large, more than three times the size of the gender gap, but at the same time only about one-third of the size of the social class gap. Socio-economic variables could account for the attainment gaps for Black African, Pakistani and Bangladeshi students, but not for Black Caribbean students. Further controls for parental and student attitudes, expectations and behaviours indicated minority ethnic groups were on average more advantaged on these measures than White British students, but this was not reflected proportionately in their levels of attainment. Black Caribbean students were distinctive as the only group making less progress than White British students between age 11 and 14 and this could not be accounted for by any of the measured contextual variables. Possible explanations for the White British-Black Caribbean gap are considered

Optimal univariate expectations under high and persistent inflation: New evidence from Turkey

The poor performance of sticky-price models with rational expectations in explaining the inflationary inertia in the US economy constitutes the basis for sticky-price models of near-rational expectations in the recent literature. However, previous studies on inflationary inertia in Turkey not only lack a model of nominal stickiness but also do not try to explain inflation persistence by expectations. Even though, there exists evidence for persistent inflation in Turkey as confirmed by earlier studies, and other studies provide evidence that expectations are neither perfectly rational nor purely adaptive, there is no attempt to link this near-rational behavior to inflationary inertia. Given this gap, this paper, therefore, tests empirically a sticky-price model under the assumption of near-rational expectations on two different inflation episodes in the Turkish economy. The near-rational expectations as described by optimal univariate expectations where agents use information on past inflation optimally while data on other variables are ignored, not only fit the data for both periods but also are not subject to Lucas critique. Alternatively, near-rational expectations are assumed to be backward looking. This alternative scenario shows that optimal univariate expectations perform even better during relatively higher inflation periods. © 2004 Elsevier B.V. All rights reserved