Wheeled PROPs, graph complexes and the master equation

in Journal of Pure and Applied Algebra (2009), 213(4), 496-535

We introduce and study wheeled PROPs, an extension of the theory of PROPs which can treat traces and, in particular, solutions to the master equations which involve divergence operators. We construct a dg ... [more ▼]

We introduce and study wheeled PROPs, an extension of the theory of PROPs which can treat traces and, in particular, solutions to the master equations which involve divergence operators. We construct a dg free wheeled PROP whose representations are in one-to-one correspondence with formal germs of SP-manifolds, key geometric objects in the theory of Batalin–Vilkovisky quantization. We also construct minimal wheeled resolutions of classical operads Com and Ass as non-trivial extensions of the well-known dg operads Com-infinityand Ass-infinity source. Finally, we apply the above results to a computation of cohomology of a directed version of Kontsevich’s complex of ribbon graphs. [less ▲]

Systems biology towards life in silico: mathematics of the control of living cells.

in Journal of Mathematical Biology (2009), 58(1-2), 7-34

Systems Biology is the science that aims to understand how biological function absent from macromolecules in isolation, arises when they are components of their system. Dedicated to the memory of Reinhart ... [more ▼]

Systems Biology is the science that aims to understand how biological function absent from macromolecules in isolation, arises when they are components of their system. Dedicated to the memory of Reinhart Heinrich, this paper discusses the origin and evolution of the new part of systems biology that relates to metabolic and signal-transduction pathways and extends mathematical biology so as to address postgenomic experimental reality. Various approaches to modeling the dynamics generated by metabolic and signal-transduction pathways are compared. The silicon cell approach aims to describe the intracellular network of interest precisely, by numerically integrating the precise rate equations that characterize the ways macromolecules' interact with each other. The non-equilibrium thermodynamic or 'lin-log' approach approximates the enzyme rate equations in terms of linear functions of the logarithms of the concentrations. Biochemical Systems Analysis approximates in terms of power laws. Importantly all these approaches link system behavior to molecular interaction properties. The latter two do this less precisely but enable analytical solutions. By limiting the questions asked, to optimal flux patterns, or to control of fluxes and concentrations around the (patho)physiological state, Flux Balance Analysis and Metabolic/Hierarchical Control Analysis again enable analytical solutions. Both the silicon cell approach and Metabolic/Hierarchical Control Analysis are able to highlight where and how system function derives from molecular interactions. The latter approach has also discovered a set of fundamental principles underlying the control of biological systems. The new law that relates concentration control to control by time is illustrated for an important signal transduction pathway, i.e. nuclear hormone receptor signaling such as relevant to bone formation. It is envisaged that there is much more Mathematical Biology to be discovered in the area between molecules and Life. [less ▲]

On the Principles of Multicell Precoding with Centralized and Distributed Cooperation Björnson, Emi Ottersten, Björn

in Wireless Communications & Signal Processing, 2009. WCSP 2009. International Conference on (2009)

Cooperative precoding is an attractive way of improving the performance in multicell downlink scenarios. By serving each terminal through multiple surrounding base stations, inter-cell interference can be ... [more ▼]

Cooperative precoding is an attractive way of improving the performance in multicell downlink scenarios. By serving each terminal through multiple surrounding base stations, inter-cell interference can be coordinated and higher spectral efficiency achieved, especially for terminals at cell edges. The optimal performance of multicell precoding is well-known as it can be treated as a single cell with distributed antennas. However, the requirements on backhaul signaling and computational power scales rapidly in large and dense networks, which often makes such fully centralized approaches impractical. In this paper, we review and generalize some recent work on multicell precoding with both centralized and distributed cooperation. We propose practical precoding strategies under Rician channel conditions, and illustrate how the major gain of multicell precoding originates from having good base station synchronization and not from making centralized precoding decisions. [less ▲]

Präpuls-Inhibierung der kardiovaskulären Schreckreaktion

in Widmann, A.; Andersen, S. K.; Friederici, A. D. (Eds.) et al 35. Arbeitstagung Psychophysiologie und Methodik (2009)

The Design of Convivial Multiagent Systems

in Social Networks and Multiagent Systems symposium; Artificial Intelligence and Simulation of Behaviour, AISB, April 6-9, 2009 at the Heriot-Watt University, Edinburgh (Scotland). (2009)

Recommendations pour l'optimisation de la formation des enseignants de langues en Europe

in SemLang (2009)

Ce document constitue une synthèse des enseignements tirés de l’Université d’été SemLang (Sèvres, 6-10 juillet 2009). Il présente les grandes lignes du projet, la méthodologie utilisée, et propose une ... [more ▼]

Ce document constitue une synthèse des enseignements tirés de l’Université d’été SemLang (Sèvres, 6-10 juillet 2009). Il présente les grandes lignes du projet, la méthodologie utilisée, et propose une série de recommandations. Celles-ci sont fondées sur les conclusions des conférences et des ateliers, sur l’interaction entre les participants, ainsi que sur le rapport analytique créé par le consortium. [less ▲]

Related-Key Cryptanalysis of the Full AES-192 and AES-256

in ASIACRYPT 2009 (2009)

In this paper we present two related-key attacks on the full AES. For AES-256 we show the first key recovery attack that works for all the keys and has 2^99.5 time and data complexity, while the recent ... [more ▼]

In this paper we present two related-key attacks on the full AES. For AES-256 we show the first key recovery attack that works for all the keys and has 2^99.5 time and data complexity, while the recent attack by Biryukov-Khovratovich-Nikolic works for a weak key class and has much higher complexity. The second attack is the first cryptanalysis of the full AES-192. Both our attacks are boomerang attacks, which are based on the recent idea of finding local collisions in block ciphers and enhanced with the boomerang switching techniques to gain free rounds in the middle. [less ▲]

Reactive Preferencial Structures and Nonmonotonic consequence

in Review of Symbolic Logic (2009)

Understanding young people’s citizenship learning in everyday life: The role of contexts, relationships and dispositions.

in Education, Citizenship and Social Justice [=ECSJ] (2009), 4(1), 5-24

Energy and Cost Optimization through Semi-central Sludge Treatment Centre

Scientific Conference (2009)