Self tolerance in a minimal model of the idiotypic network

We consider the problem of self tolerance in the frame of a minimalistic model of the idiotypic network. A node of this network represents a population of B lymphocytes of the same idiotype which is encoded by a bit string. The links of the network connect nodes with (nearly) complementary strings. The population of a node survives if the number of occupied neighbours is not too small and not too large. There is an influx of lymphocytes with random idiotype from the bone marrow. Previous investigations have shown that this system evolves toward highly organized architectures, where the nodes can be classified into groups according to their statistical properties. The building principles of these architectures can be analytically described and the statistical results of simulations agree very well with results of a modular mean field theory. In this paper we present simulation results for the case that one or several nodes, playing the role of self, are permanently occupied. We observe that the group structure of the architecture is very similar to the case without self antigen, but organized such that the neighbours of the self are only weakly occupied, thus providing self tolerance. We also treat this situation in mean field theory which give results in good agreement with data from simulation.Comment: 7 pages, 6 figures, 1 tabl

Institutionalizing alternative economic spaces? An interpretivist perspective on diverse economies

This article offers an approach that helps geographers and others to carefully and critically reexamine prospects for diverse economies. We propose an interpretative institutionalist perspective is useful for elucidating overlooked opportunities for creating alternative economic visions and practices by revealing the process of ‘meaning making’ undertaken by actors in the process of developing policy responses to various dilemmas. We explore this notion in the context of de-growth or post-growth. De-growth is a way of thinking about the economy in ways that are not growth oriented, or fixated on GDP, but on the redistribution of wealth and living within the Earth’s ecosystems

Integrated multi vector vortex beam generator

A novel method to generate and manipulate vector vortex beams in an integrated, ring resonator based geometry is proposed. We show numerically that a ring resonator, with an appropriate grating, addressed by a vertically displaced access waveguide emits a complex optical field. The emitted beam possesses a specific polarization topology, and consequently a transverse intensity profile and orbital angular momentum. We propose a combination of several concentric ring resonators, addressed with different bus guides, to generate arbitrary orbital angular momentum qudit states, which could potentially be used for classical and quantum communications. Finally, we demonstrate numerically that this device works as an orbital angular momentum sorter with an average cross-talk of -10 dB between different orbital angular momentum channels.Comment: 8 pages, 7 figure

Employee Retention Strategies of the U.S. Power Industry

Employee turnover in the U.S. power industry continues to be a challenging issue. Leaders of U.S. power organizations tend to be concerned about employee turnover, which has a negative impact on productivity and profitability. Grounded in Herzberg’s hygiene-motivator theory, the purpose of this qualitative pragmatic inquiry was to identify and explore successful strategies that some U.S. power company leaders use to improve employee retention. The participants were seven business leaders from seven power companies across the Midwestern United States who successfully implemented strategies to improve employee retention. Data were collected using semistructured interviews and company website information. Through thematic analysis, four themes were identified: (a) a happy work environment characterized by communication and trust, (b) work relationships centered around treatment and teamwork, (c) workplace policies that showed some leniency and flexibility, and (d) job engagement. A key recommendation is for power organization leaders to develop a workplace environment that is engaging and promotes a healthy work-life balance. The implications for positive social change include the potential to improve employee retention and corporate profitability, which can increase tax revenues that can be used to support community programs

Employee Retention Strategies of the U.S. Power Industry

Employee turnover in the U.S. power industry continues to be a challenging issue. Leaders of U.S. power organizations tend to be concerned about employee turnover, which has a negative impact on productivity and profitability. Grounded in Herzberg’s hygiene-motivator theory, the purpose of this qualitative pragmatic inquiry was to identify and explore successful strategies that some U.S. power company leaders use to improve employee retention. The participants were seven business leaders from seven power companies across the Midwestern United States who successfully implemented strategies to improve employee retention. Data were collected using semistructured interviews and company website information. Through thematic analysis, four themes were identified: (a) a happy work environment characterized by communication and trust, (b) work relationships centered around treatment and teamwork, (c) workplace policies that showed some leniency and flexibility, and (d) job engagement. A key recommendation is for power organization leaders to develop a workplace environment that is engaging and promotes a healthy work-life balance. The implications for positive social change include the potential to improve employee retention and corporate profitability, which can increase tax revenues that can be used to support community programs

The Portrayal of the German in Russian Novels - Gončarov, Turgenev, Dostoevskij, Tolstoj

It is the intention of this dissertation to investigate, as thoroughly as possible, the portrayal of the German as he appears in the prose works (drama and poetry have been excluded) of four of Russia's greatest nineteenth-century literary writers- I. A, Gončarov, I. S. Turgenev, F. M. Dostoevskij, and L. N. Tolstoj