The pattern memory of gene-protein networks

In this paper we study the potential of gene-protein interaction networks to store input-output patterns. The central question in this study concerns the memory capacity of a network of a given number of genes and proteins, which interact according to a linear state space model with external inputs. Here it is assumed that to a certain combination of inputs there exists an optimal state of the system, i.e., values of the gene expressions and protein levels, that has been attained externally, e.g., through evolutionary learning. Given such a set of learned optimal input-output patterns, the design question here is to find a sparse and hierarchical network structure for the gene-protein interactions and the gene-input couplings. This problem is formulated as an optimization problem in a linear programming setting. Numerical analysis shows that there are clear scale-invariant continuous secondorder phase transitions for the network sparsity as the number of patterns increases. These phase transitions divide the system in three regions with different memory characteristics. It is possible to formulate simple scaling rules for the behavior of the network sparsity. Finally, numerical experiments show that these patterns are stable within a certain finite range around the patterns

On Phase Transitions in Learning Sparse Networks

Abstract. In this paper we study the identification of sparse interaction networks as a machine learning problem. Sparsity means that we are provided with a small data set and a high number of unknown components of the system, most of which are zero. Under these circumstances, a model needs to be learned that fits the underlying system, capable of generalization. This corresponds to the studentteacher setting in machine learning. In the first part of this paper we introduce a learning algorithm, based on L 1 -minimization, to identify interaction networks from poor data and analyze its dynamics with respect to phase transitions. The efficiency of the algorithm is measured by the generalization error, which represents the probability that the student is a good fit to the teacher. In the second part of this paper we show that from a system with a specific system size value the generalization error of other system sizes can be estimated. A comparison with a set of simulation experiments show a very good fit

Low serum creatine kinase in patients with infective endocarditis

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Recommandations pour la prise en charge de douleurs thoraciques aiguës

The Belgium Interdisciplinary Working Group on Acute Cardiology (BIWAC), including cardiologists, intensivists and urgentists was formed to give consensus regarding the management of acute chest pain in the prehospital and the early hospital phases. General recommendations and critical pathways are proposed to improve the treatment of the patients with acute coronary syndromes.SCOPUS: re.jinfo:eu-repo/semantics/publishe

Recommandations pour la prise en charge de douleurs thoraciques aiguës. Rapport du Groupe Interdisciplinaire Belge de Cardiologie Aiguë

The Belgium Interdisciplinary Working Group on Acute Cardiology (BIWAC), including cardiologists, intensivists and urgentists was formed to give consensus regarding the management of acute chest pain in the prehospital and the early hospital phases. General recommendations and critical pathways are proposed to improve the treatment of the patients with acute coronary syndromes.SCOPUS: ar.jinfo:eu-repo/semantics/publishe

Praktische aanbevelingen bij de aanpak van acute ritmestoornissen: Verslag van de Belgische Interdisciplinaire Werkgroep van Acute Cardiologie (BIWAC)

Acute arrhythmia is a condition covering a wide variety of rhythm disturbances. The aim of this article is to give practical recommendations for the management of the patient presenting with an acute arrhythmia. We discuss bradycardia and tachycardia. Tachycardias are divided into the small QRS complex tachycardias and the wide QRS complex tachycardias. Other important issues are the distinction between the hemodynamic stable and unstable patient and the need for trombo-embolic prevention of the patient with atrial fibrillation. Flowcharts with diagnostic means and therapeutic schemes as well as a table with practical considerations for electrical cardioversion are provided.SCOPUS: re.jinfo:eu-repo/semantics/publishe