Radiation from a charge circulating inside a waveguide with dielectric filling

The emitted power of the radiation from a charged particle moving uniformly on a circle inside a cylindrical waveguide is considered. The expressions for the energy flux of the radiation passing through the waveguide cross-section are derived for both TE and TM waves. The results of the numerical evaluation are presented for the number of emitted quanta depending on the waveguide radius, the radius of the charge rotation orbit and dielectric permittivity of the filling medium. These results are compared with the corresponding quantities for the synchrotron radiation in a homogeneous medium.Comment: 10 pages, Latex, four EPS figure

Tartaric Acid Synthetic Derivatives for Multi-Drug Resistant Phytopathogen Pseudomonas and Xanthomonas Combating

The resistance to antimicrobial preparations, according the WHO reports of recent years, is becoming the one of the most actual healthcare problems of this century. Nevertheless, the key role of antibiotics diversity increase, as well as the increase of their application scopes, the initial origin of antimicrobial resistance problem is the versatility of adaptation mechanisms potential of all microorganisms, including intraspecific gene horizontal transfer and quorum sensing. Thus, the actuality of search of new, ecologically safe and harmless for human health antimicrobial agents, among the natural and semisynthetic compounds, is being significantly increased. One of the prospective directions in these research is the derivatization of aldaric acids, isolated from plants different species, as the native antibacterial active substances, such as like: citric, acetic, tartaric, lactic.   In current research, 7 new derivatives of natural tartaric acid (TA): cyclohexylimide, benzylimide, phenylimide, benzyl mono amino salt, cyclohexyl mono amino salt, phenyl amino salt and mono ethanol amino salt of TA were tested on different strains from 6 subtypes of 3 species of phytopathogenic multi-drug resistant Xanthomonas and Pseudomonas. During the research it was detected the significant antimicrobial effect of studied compounds against the range of phytopathogens which are resistant to antibiotics from different classes and generations (ciprofloxacin, chloramphenicol, ceftriaxone, azithromycin, etc.). It was detected the higher efficiency of cyclohexyl- derivatives in comparison with mono ethanol-, phenyl- and benzyl- derivatives

Topics on firm heterogeneity and economic policy

This thesis presents a series of works exploring individual firm behavior and how that affects the macroeconomics data. Chapter one explores the trends in competition, markups and market shares in a general equilibrium model. Over the last 30 years markups, as well as advertising expenses, have increased substantially. Moreover, there is a positive correlation between marketing expenditures and markups, a feature that standard models of monopolistic competition based on Dixit-Stiglitz have found it difficult to obtain. The model here adds endogenous market expansion choice (through product marketing) for firms to an otherwise standard monopolistic competition model. The marketing is modeled as a contest in which heterogeneous firms can shift the demand of the variety they produce, but also suffer from other firms engaging in the same activity. In the model's equilibrium, product marketing and pricing decisions interact with each other, altering markups proportional to the level of marketing expenditures by individual firms. This is another result that many empirical studies find. The model also creates a link between total factor productivity and markups through investments in product marketing. The model shows that markups and market concentration depends on the variance of total factor productivity. It also illustrates how the elasticity of substitution in an industry can affect the markup distribution. The second chapter is based on the work co-authored with Dr. Mattias Polborn, where we analyze a theoretical model in which entrepreneurs' property rights are threatened by ``raiders'' who can challenge them to a contest for control of their firms. Entrepreneurs have heterogeneous productivity and decide how much capital to invest before raiders decide whom to attack. In equilibrium, low productivity entrepreneurs are unaffected by the existence of raiders, while mid- and high-productivity entrepreneurs suffer. However, while raiders essentially act as a tax for the highest productivity entrepreneurs, the investment behavior of mid-productivity entrepreneurs who try to avoid an attack is more drastically affected. Our model provides a novel theoretical explanation for the ``missing middle'' observed in many countries with insecure property rights. The third chapter analyses the effects of monetary policy on firm's investment decision by adding technology investments into otherwise standard New Keynesian models. In standard New Keynesian models growth rate of the economy is assumed to be exogenous and out of the scopes of monetary authority's control. The framework developed here adds stochastic growth rates determined from firm-specific investments. Firms carry costs from price adjustments and can accumulate technology by technological investments, which aggregates as a level of technology in the economy. Under this setup inflation and monetary shocks have a considerably large impact on the growth rates of the economy. Interest rate change counteracting cycle interferes with growth and the variable levels. Policy rules that penalize for inflation more perform more favorably under this setup.U of I OnlyAuthor requested U of Illinois access only (OA after 2yrs) in Vireo ETD syste

A Theory of Auditability for Allocation and Social Choice Mechanisms

In centralized market mechanisms individuals may not fully observe other participants' type reports. Hence, the mechanism designer may deviate from the promised mechanism without the individuals being able to detect these deviations. In this paper, we develop a general theory of auditability for allocation and social choice problems. We find a stark contrast between the auditabilities of prominent mechanisms: the Immediate Acceptance mechanism is maximally auditable, in a sense that any deviation can always be detected by just two individuals, whereas, on the other extreme, the Deferred Acceptance mechanism is minimally auditable, in a sense that some deviations may go undetected unless some individuals possess full information about everyone's reports. There is a similar contrast between the first-price and the second-price auction mechanisms. Additionally, we give a simple characterization of the majority voting mechanism for social choice problems, and we evaluate the auditability of reserves mechanisms for choice with affirmative action