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3002. Bilinear system as a modelling framework for analysis of microalgal growth
- Creator:
- Papáček, Štefan, Čelikovský, Sergej, Štys, Dalibor, and Ruiz-León, Javier
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- bilinear system, model of photosynthetic factory, microalgae, light / dark cycles, and flashing light experiments
- Language:
- English
- Description:
- A mathematical model of the microalgal growth under various light regimes is required for the optimization of design parameters and operating conditions in a photobioreactor. As its modelling framework, bilinear system with single input is chosen in this paper. The earlier theoretical results on bilinear systems are adapted and applied to the special class of the so-called intermittent controls which are characterized by rapid switching of light and dark cycles. Based on such approach, the following important result is obtained in the present paper: as the light/dark cycle frequency is going to infinity, the value of resulting production rate in the microalgal culture goes to a certain limit value, which depends on average irradiance in the culture only. As a case study, the so-called three-state model of photosynthetic factory, being a simple four-parameter model, is analyzed. The present paper shows various numerical simulations for the model parameters previously published and analyzed experimentally in the biotechnological literature. These simulation results are in a very good qualitative compliance with the well-known flashing light experiments, thereby confirming viability of the approach presented here.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3003. Bilirubin and atherosclerotic diseases
- Creator:
- Libor Vítek
- Format:
- print, bez média, and svazek
- Type:
- article, články, journal articles, model:article, and TEXT
- Subject:
- Fyziologie člověka a srovnávací fyziologie, bilirubin, ateroskleróza, kardiovaskulární nemoci, atherosclerosis, cardiovascular diseases, benign hyperbilirubinemia, Gilbert syndrome, 14, and 612
- Language:
- English
- Description:
- Bilirubin is the final product of heme catabolism in the systemic circulation. For decades, increased serum/plasma bilirubin levels were considered an ominous sign of an underlying liver disease. However, data from recent years convincin gly suggest that mildly elevated bilirubin concentrations are as sociated with protection against various oxidative stress-mediated diseases, atherosclerotic conditions being the most clinically relevant. Although scarce data on beneficial effects of bilirubin had been published also in the past, it took until 1994 when the first clinical study demonstrated an increased risk of coronary heart disease in subjects with low serum bilirubin levels, and bilirubin was found to be a risk factor for atherosclerotic diseases independent of standard risk factors. Consistent with t hese results, we proved in our own studies, that subjects with mild elevation of serum levels of unconjugated bilirubin (benign hyperbilirubinemia, Gilbert syndrome) have much lower prevalence/incidence of cor onary heart as well as peripher al vascular disease. We have also demonstrated that this association is even more general, with serum bilirubin being a biomarker of numerous other diseases, often associated with increased risk of atherosclerosis. In addition, very recent data have demonst rated biological pathways modulated by bilirubin, which are responsible for observed strong clinical associations., L. Vítek., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3004. Bílý a multikulturní feminismus: sebekritika a proměny feministického hnutí
- Creator:
- Víznerová, Hana
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Czech
- Description:
- Autor recenze: Hana Víznerová
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3005. Binaries and evolution of globular clusters
- Creator:
- Stodółkiewicz, J. S.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- astronomy, globular clusters, and binaries
- Language:
- Czech
- Description:
- The influence of binaries on the evolution of globular clusters is studied numerically using the Monte Carlo method. It is assumed that initially the stellar systems are composed of single stars only and binaries are born /as a result of three-body encounters/ during the evolution of the clusters. The life of each hard binary in the cluster is studied individually. It is shown that the first binaries appear long before core collapse is completed, and then a population of a few hard binaries remains in the cluster during its whole life. Practically all energetic binary-single star interactions take place in the deep, internal parts of the core, populated mostly by the heaviest stars of the cluster. The binary-single star interactions become a source of energy which stops the collapse of the core and causes expansion and gradual disintegration of the whole cluster during the post-collapse phase.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3006. Binarizace počítačem generovaného hologramu pomocí ditheringu
- Creator:
- Lobaz, Petr and Kovář, Libor
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- diffraction, optical diffraction gratingseczenas, difrakce, and optické difrakční mřížky
- Language:
- Czech
- Description:
- Pokračování článku z čísla 10/2011
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3007. Binarizace počítačem generovaného hologramu pomocí ditheringu
- Creator:
- Lobaz, Petr and Kovář, Libor
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- diffraction, diffraction grating, computer generated hologram, binarization, dithering, difrakce, difrakční mřížka, počítačem generovaný hologram, and binarizace
- Language:
- Czech
- Description:
- The article discusses the display of computer generated holograms of 3D objects using a binary amplitude spatial light modulator. More precisely, it deals with binarization of a diffractive structure using dithering noise. It concludes that the dithering method is suitable for simple diffractive structures such as diffractive gratings, but fails to provide a good binarization of computer generated holograms of 3D objects., Článek se zabývá zobrazením počítačem generovaného hologramu 3D objektu na binárním amplitudovém prostorovém modulátoru světla, respektive binarizací difraktivních struktur. Rozvíjí myšlenku binarizace difraktivní struktury pomocí techniky ditheringu. Dospívá k závěru, že technika je vhodná pro jednoduché struktury typu difrakční mřížky, ale není vhodná pro počítačem generované hologramy 3D objektu., and Pokračování článku v příštím čísle
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3008. Binarův čin: Vladimír Binar: Čin a slovo: Kniha o Jakubu Demlovi
- Creator:
- Sytař, Pavel
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3009. Binary evolution
- Creator:
- de Loore, C.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- astrophysics and binary evolution
- Language:
- Czech
- Description:
- Consideration of mass transfer and mass loss processes allows the explanation of the existence of well determined groups of binaries, such as Algols, cataclysmic variables, massive and low masa X ray binaries. The characteristics of these groups are briefly outlined, and evolutionary scenarios are discussed. The importance of detailed observations for advances in evolutionary computations are stressed. It isargued that, although the linka between the mentionned groups of binaries and their progenitors is rather well known, the situation is completely different if the detailed evolutionary history for a given system is required.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public
3010. Binary factorization in Hopfield-like neural networks: single-step approximation and computer simulations
- Creator:
- Frolov, A. A., Sirota, A. M., Húsek, D., Muraviev, I. P., and Polyakov, P. A.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- nonlinear binary factor analysis, feature extraction, recurrent neural network, Single-Step approximation, neurodynamics simulation, attraction basins, Hebbian learning, unsupervised learning, neuroscience, and brain functions modeling
- Language:
- English
- Description:
- The unsupervised learning of feature extraction in high-dimesional patterns is a central problem for the neural network approach. Feature extraction is a procedure which maps original patterns into the feature (or factor) space of reduced dimension. In this paper we demonstrate that Hebbian learning in Hopfield-like neural network is a natural procedure for unsupervised learning of feature extraction. Due to this learning, factors become the attractors of network dynamics, hence they can be revealed by the random search. The neurodynamics is analysed by Single-Step approximation which is known [8] to be rather accurate for sparsely encoded Hopfield-network. Thus, the analysis is restricted by the case of sparsely encoded factors. The accuracy of Single-Step approximation is confirmed by Computer simulations.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public