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Dynamics underlying epileptic seizures span multiple scales in space and time, therefore, understanding seizure mechanisms requires identifying the relations between seizure components within and across these scales, together with the analysis of their dynamical repertoire. In this view, mathematical models have been developed, ranging from single neuron to neural population.In this study we consider a neural mass model able to exactly reproduce the dynamics of heterogeneous spiking neural networks. We combine the mathematical modelling with structural information from non-invasive brain imaging, thus building large-scale brain network models to explore emergent dynamics and test clinical hypothesis. We provide a comprehensive study on the effect of external drives on neuronal networks exhibiting multistability, in order to investigate the role played by the neuroanatomical connectivity matrices in shaping the emergent dynamics. In particular we systematically investigate the conditions under which the network displays a transition from a low activity regime to a high activity state, which we identify with a seizure-like event. This approach allows us to study the biophysical parameters and variables leading to multiple recruitment events at the network level. We further exploit topological network measures in order to explain the differences and the analogies among the subjects and their brain regions, in showing recruitment events at different parameter values.We demonstrate, along the example of diffusion-weighted magnetic resonance imaging (MRI) connectomes of 20 healthy subjects and 15 epileptic patients, that individual variations in structural connectivity, when linked with mathematical dynamic models, have the capacity to explain changes in spatiotemporal organization of brain dynamics, as observed in network-based brain disorders. In particular, for epileptic patients, by means of the integration of the clinical hypotheses on the epileptogenic zone (EZ), i.e. the local network where highly synchronous seizures originate, we have identified the sequence of recruitment events and discussed their links with the topological properties of the specific connectomes. The predictions made on the basis of the implemented set of exact mean-field equations turn out to be in line with the clinical pre-surgical evaluation on recruited secondary networks.

A highly structured eta solar cell of the type TiO2/In(OH)xSy/Pb(OH)xSy/PEDOT:PSS/Au with different layer thickness has been fabricated using various deposition techniques for each layer in the stack. The solar cell parameters, Uoc, FF and 14η"> have been extracted from current- voltage characteristics measurements. The buffer layer and the hole collector layer have been kept constant while the window and the absorber layer have been varied. The thickness of either of the two layers being varied has been observed to affect the performance of the solar cells. The difference in thickness has been attributed to affect the charge lifetime in the space charge region therefore affecting the performance of the solar cell.Keywords: Thin film; TiO2; eta solar cell; photovoltaic; spray pyrolysis; chemical bath

International audience; The potential of the diverse chemistries present in natural products (NP) for biotechnology and medicine remains untapped because NP databases are not searchable with raw data and the NP community has no way to share data other than in published papers. Although mass spectrometry (MS) techniques are well-suited to high-throughput characterization of NP, there is a pressing need for an infrastructure to enable sharing and curation of data. We present Global Natural Products Social Molecular Networking (GNPS; http://gnps.ucsd.edu), an open-access knowledge base for community-wide organization and sharing of raw, processed or identified tandem mass (MS/MS) spectrometry data. In GNPS, crowdsourced curation of freely available community-wide reference MS libraries will underpin improved annotations. Data-driven social-networking should facilitate identification of spectra and foster collaborations. We also introduce the concept of 'living data' through continuous reanalysis of deposited data.

International audience; In this study, we examined the antiviral properties of Khaya grandifoliola C.DC (Meliaceae) on the hepatitis C virus (HCV) life cycle in vitro and identified some of the chemical constituents contained in the fraction with the most antiviral activity. Dried bark powder was extracted by maceration in a methylene chloride/methanol (MCM) system (50:50; v/v) and separated on silica gel by flash chromatography. Infection and replication rates in Huh-7 cells were investigated by luciferase reporter assay and indirect immunofluorescence assay using subgenomic replicons, HCV pseudotyped particles, and cell-culture-derived HCV (HCVcc), respectively. Cell viability was assessed by MTT assay, and cellular gene expression was analysed by qRT-PCR. The chemical composition of the fraction with the most antiviral activity was analysed by coupled gas chromatography and mass spectrometry (GC-MS). Five fractions of different polarities (F0-F100) were obtained from the MCM extract. One fraction (KgF25) showed the strongest antiviral effect on LucUbiNeoET replicons at nontoxic concentrations. Tested at 100 µg/mL, KgF25 had a high inhibitory effect on HCV replication, comparable to that of 0.01 µM daclatasvir or 1 µM telaprevir. This fraction also inhibited HCVcc infection by mostly targeting the entry step. KgF25 inhibited HCV entry in a pan-genotypic manner by directly inactivating free viral particles. Its antiviral effects were mediated by the transcriptional upregulation of the haem oxygenase-1 gene and interferon antiviral response. Three constituents, namely, benzene, 1,1'-(oxydiethylidene)bis (1), carbamic acid, (4-methylphenyl)-, 1-phenyl (2), and 6-phenyl, 4-(1'-oxyethylphenyl) hexene (3), were identified from the active fraction KgF25 by GC-MS. Khaya grandifoliola contains ingredients capable of acting on different steps of the HCV life cycle.

The article provides an analysis of the reporting about the Euromaidan actions of the three biggest German weekly magazines. The content analysis based on specific keywords will show, which politicians and events the journalists refer to. As a part of media reporting about the events that took place in Ukraine 2013–2014, the analysis will show an example of the topics German media talk about. It is obvious that well known Ukrainian politicians, such as Vitali Klitschko or Yulia Tymoshenko, are interviewed. Other politicians, such as Arseniy Yatsenyuk or Oleh Tyahnibok, barely appear in the reportings of the three weekly magazines. They are neither interviewed nor shown in detail. They seem to stand in the background of box champion Vitali Klitschko, who is very well known in Germany. The magazines call him “opposition leader” (that is wrong, he was one of the leaders of the opposition) and “the next strong man in Kiev. The reporting is centered on Tymoshenko and Klitschko. Another conclusion that can be made from the analysis is the perspective of the journalists. The conflict in Ukraine is mostly shown in the German-Russian-relationship and just marginally focused on Ukraine itself. Often, the consequences for Germany and the European economy are discussed. W artykule przedstawiono analizę sprawozdań nt. wydarzeń określanych mianem Euromajdanu, zaczerpniętych z trzech największych niemieckich tygodników. Analiza treści na podstawie określonych słów kluczowych pokazuje, jak niemieccy politycy i dziennikarze wydarzenia te rozumieją i interpretują. Czymś oczywistym jest obecność wywiadów z dobrze znanymi politykami ukraińskimi, takimi jak Witalij Kliczko czy Julia Tymoszenko. Inni politycy jednak, jak Arsenij Jaceniuk lub Ołeh Tiahnybok, ledwie pojawiają się w doniesienia tych tygodników. Brakuje zarówno wywiadów z nimi, jak i szczegółowych informacji na temat ich osób i działalności. Sporo uwagi niemieckich mediów koncentruje na sobie Witalij Kliczko, słynny w Niemczech bokser. Magazyny nazywają go „liderem opozycji” (co nie jest do końca zgodne z prawdą, bo był on tylko jednym z liderów), a także „następnym silnym człowiekiem w Kijowie”. Doniesienia skupiają się na Tymoszenko i Kliczce. Kolejny wniosek, jaki może być wyciągnięty z analizy dotyczy perspektywy dziennikarzy. Konflikt na Ukrainie pokazywany jest głównie na tle relacji niemiecko-rosyjskich i tylko jako marginalnie dotyczący samej Ukrainy. Często omawiane są kwestie istotne dla Niemiec i gospodarki europejskiej.

Cette version inclut le code source du programme Bianchi.gp, qui a été développé pour cette thèse. Il se trouve dans les fichiers "ANNEX".; This thesis consists of the study of the geometry of a certain class of arithmetic groups, by means of a proper action on a contractible space. We will explicitly compute their group homology, and their equivariant K-homology. More precisely, consider an imaginary quadratic number field, and its ring of integers R. The Bianchi groups are the groups SL_2(R) and PSL_2(R). These groups act in a natural way on hyperbolic three-space. The Bianchi groups are a key to the study of a larger class of groups, the Kleinian groups, which dates back to works of Poincaré. In fact, each non-cocompact arithmetic Kleinian group is commensurable with some Bianchi group. The author has implemented the computation of a fundamental domain for the Bianchi groups. By computing the stabilisers and identifications on this fundamental domain, we obtain an explicit orbifold structure. We use it to study different aspects of the geometry of our groups. Firstly, we compute group homology with integer coefficients, using the equivariant Leray/Serre spectral sequence. Secondly, we compute the Bredon homology of the Bianchi groups, from which we deduce their equivariant K-homology. By the Baum/Connes conjecture, which is verified by the Bianchi groups, we obtain the K-theory of the reduced C*-algebras of the Bianchi groups, as isomorphic images. Finally, we complexify our orbifolds, by complexifying the real hyperbolic three-space. We obtain orbifolds given by the induced action of the Bianchi groups on complex hyperbolic three-space. Then we compute the Chen/Ruan orbifold cohomology for these complex orbifolds. This is one side of Ruan's cohomological crepant resolution conjecture.; Cette thèse consiste d'une étude de la géométrie d'une certaine classe de groupes arithmétiques, à travers d'une action propre sur un espace contractile. Nous calculons explicitement leur homologie de groupe, et leur K-homologie équivariante. Plus précisément, considérons un corps de nombres quadratique imaginaire et son anneau d'entiers A. Les groupes de Bianchi sont les groupes SL_2(A) et PSL_2(A). Ces groupes agissent d'une manière naturelle sur l'espace hyperbolique à 3 dimensions. Ils constituent une clef pour l'étude d'une classe plus large de groupes, les groupes Kleiniens, étudiés depuis Poincaré. En fait, chaque groupe Kleinien arithmétique non-cocompact est commensurable avec un des groupes de Bianchi. L'auteur a implémenté à l'ordinateur, le calcul d'un domaine fondamental pour ces groupes. En calculant les stabilisateurs et identifications sur ce domaine fondamental, nous obtenons une structure explicite d'orbi-espace. Nous nous en servons pour étudier des aspects différents de la géométrie des groupes de Bianchi. D'abord, nous calculons l'homologie de groupe à coefficients entiers, à l'aide de la suite spectrale équivariante de Leray/Serre. Ensuite, nous calculons l'homologie de Bredon de groupes de Bianchi, de laquelle nous déduisons leur K-homologie équivariante. Par la conjecture de Baum/Connes, qui est vérifiée par nos groupes, nous obtenons la K-théorie des C*-algèbres réduites de nos groupes. Finalement, nous complexifions nos orbi-espaces, en complexifiant l'espace hyperbolique. Ceci nous permet de calculer la cohomologie d'orbi-espace de Chen/Ruan, qui est l'un des deux côtés de la conjecture de la résolution cohomologique crépante de Ruan.

International audience; Contamination of magmas by country rocks may contribute xenoliths and xenocrysts to the magma, but also melt and peritectic crystals that form through incongruent melting or dissolution of the original contaminants. Identifying contaminant-derived peritectic crystals and former melt components in igneous rocks is particularly challenging, but also particularly important, because their assimilation significantly affects melt composition and magma temperature. To facilitate the identification of peritectic crystals in igneous rocks, the aim of this study was to experimentally control partial assimilation of xenocrysts and examine the formation, textures, and composition of resulting peritectic crystals. Our experiments mimic contaminant melting and contamination of a partially crystallized basaltic andesite by melanorite- and monzodiorite-derived xenocrysts and micro-xenoliths. Micro-xenoliths and xenocrysts partially survive assimilation, and yet peritectic crystals form ~ 1/3 of all solid contaminants. Anhydrous xenocrysts either develop laterally continuous, subhedral to euhedral, and inclusion-poor overgrowths, or progressively decompose. Hydrous and partially altered xenocrysts decompose to peritectic crystals. The peritectic crystals form clusters of subhedral to euhedral, randomly-oriented olivine, clinopyroxene, olivine–plagioclase, and olivine–plagioclase–clinopyroxene that texturally resemble primary magmatic crystals. We propose that natural peritectic crystals with short residence times form clusters of one or more minerals with textures as those of our experiments, and that peritectic crystals with longer residence times likely anneal to subhedral or euhedral single crystals or coarse-grained mineral clusters. They hold crucial evidence for largely assimilated country-rock components and estimates of open-system magma evolution, but the longer their magma residence time the more easily they are overlooked.

Laboratory for Foundations of Computer Science Term rewriting systems are widely used throughout computer science as they provide an abstract model of computation while retaining a comparatively simple syntax and semantics. In order to reason within large term rewriting systems, structuring operations are used to build large term rewriting systems from smaller ones. Of particular interest is whether key properties are modular, that is, if the components of a structured term rewriting system satisfy a property, then does the term rewriting system as a whole? A body of literature addresses this problem, but most of the results and proofs depend on strong syntactic conditions and do not easily generalize. Although many specific modularity results are known, a coherent framework which explains the underlying principles behind these results is lacking. This thesis posits that part of the problem is the usual, concrete and syntax-oriented semantics of term rewriting systems, and that a semantics is needed which on the one hand elides unnecessary syntactic details but on the other hand still possesses enough expressive power to model the key concepts arising from the term structure, such as substitutions, layers, redexes etc. Drawing on the concepts of category theory, such a semantics is proposed, based on the concept of a monad, generalising the very elegant treatment of equational presentations in category theory. The theoretical basis of this work is the theory of enriched monads. It is shown how structuring operations are modelled on the level of monads, and that the semantics is compositional (it preserves the structuring operations). Modularity results can now be obtained directly at the level of combining monads without recourse to the syntax at all. As an application and demonstration of the usefulness of this approach, two modularity results for the disjoint union of two term rewriting systems are proven, the modularity of confluence (Toyama's theorem) and the modularity of strong normalization for a particular class of term rewriting systems (non-collapsing term rewriting systems). The proofs in the categorical setting provide a mild generalisation of these results.

Institute for Communicating and Collaborative Systems Understanding the temporal relations which hold between situations described in a narrative is a highly complex process. The main aim of this thesis is to investigate the factors we have to take into account in order to determine the temporal coherence of a narrative discourse. In particular, aspectual information, tense, and world and context knowledge have to be considered and the interplay of all these factors must be specified. German is aspectually speaking an interesting language, because it does not possess a grammaticalised distinction between a perfective and imperfective aspect. In this thesis I examine the German aspectual system and the interaction of the factors which have an influence on the derived temporal relation for short discourse sequences. The analysis is carried out in two steps: First, the aspectual and temporal properties of German are investigated, following the cross-linguistic framework developed by Carlota S. Smith. An account for German is given which emphasises the properties which are peculiar to this language and explains why it has to be treated differently to, for example, English. The main result for the tense used in a narrative text—the Preterite—is that information regarding the end point of a described situation is based on our world knowledge and may be overridden provided context knowledge forces us to do this. Next, the more complex level of discourse is taken into account in order to derive the temporal relations which hold between the described situations. This investigation provides us with insights into the interaction of different knowledge sources like aspectual information as well as world and context knowledge. This investigation of German discourse sequences gives rise to the need for a time logic which is capable of expressing fine as well as coarse (or underspecified) temporal relations between situations. An account is presented to describe exhaustively all conceivable temporal relations within a computationally tractable reasoning system, based on the interval calculus by James Allen. However, in order to establish a coherent discourse for larger sequences, the hierarchical structure of a narrative has to be considered as well. I propose a Tree Description Grammar — a further development of Tree Adjoining Grammars — for parsing the given discourse structure, and stipulate discourse principles which give an explanation for the way a discourse should be processed. I furthermore discuss how a discourse grammar needs to distinguish between discourse structure and discourse processing. The latter term can be understood as navigating through a discourse tree, and reflects the process of how a discourse is comprehended. Finally, a small fragment of German is given which shows how the discourse grammar can be applied to short discourse sequences of four to seven sentences. The conclusion discusses the outcome of the analysis conducted in this thesis and proposes likely areas of future research.

Institute for Communicating and Collaborative Systems I present a simple Simultaneous Abstraction Calculus, where the familiar lambda-abstraction over single variables is replaced by abstraction over whole sets of them. Terms are applied to partial assignments of objects to variables. Variants of the system are investigated and compared, with respect to their semantic and proof theoretic properties. The system overcomes the strict ordering requirements of the standard lambda-calculus,and is shown to provide the kind of "non-selective" binding needed for Dynamic Montague Grammar and Discourse Representation Theory. It is closely related to a more complex system, due to Peter Aczel and Rachel Lunon, and can be used for Situation Theory in a similar way. I present versions of these theories within an axiomatic, property-theoretic framework, based on Aczels Frege Structures. The aim of this work is to provide the means for integrating various semantic theories within a formal framework,so that they can share what is common between them, and adopt from each other what is compatible with them.

Theories of dependent types have been proposed as a foundation of constructive mathematics and as a framework in which to construct certified programs. In these applications an important role is played by identity types which internalise equality and therefore are essential for accommodating proofs and programs in the same formal system. This thesis attempts to reconcile the two different ways that type theories deal with identity types. In extensional type theory the propositional equality induced by the identity types is identified with definitional equality, i.e. conversion. This renders type-checking and well-formedness of propositions undecidable and leads to non-termination in the presence of universes. In intensional type theory propositional equality is coarser than definitional equality, the latter being confined to definitional expansion and normalisation. Then type-checking and well-formedness are decidable, and this variant is therefore adopted by most implementations. However, the identity type in intensional type theory is not powerful enough for formalisation of mathematics and program development. Notably, it does not identify pointwise equal functions (functional extensionality) and provides no means of redefining equality on a type as a given relation, i.e. quotient types. We call such capabilities extensional concepts. Other extensional concepts of interest are uniqueness of proofs and more specifically of equality proofs, subset types, and propositional extensionality---the identification of equivalent propositions. In this work we investigate to what extent these extensional concepts may be added to intensional type theory without sacrificing decidability and existence of canonical forms. The method we use is the translation of identity types into equivalence relations defined by induction on the type structure. In this way type theory with extensional concepts can be understood as a high-level language for working with equivalence relations instead of equality. Such translations of type theory into itself turn out to be best described using categorical models of type theory. We thus begin with a thorough treatment of categorical models with particular emphasis on the interpretation of type-theoretic syntax in such models. We then show how pairs of types and predicates can be organised into a model of type theory in which subset types are available and in which any two proofs of a proposition are equal. This model has applications in the areas of program extraction from proofs and modules for functional programs. For us its main purpose is to clarify the idea of syntactic translations via categorical model constructions. The main result of the thesis consists of the construction of two models in which functional extensionality and quotient types are available. In the first one types are modelled by types together with proposition-valued partial equivalence relations. This model is rather simple and in addition provides subset types and propositional extensionality. However, it does not furnish proper dependent types such as vectors or matrices. We try to overcome this disadvantage by using another model based on families of type-valued equivalence relations which is however much more complicated and validates certain conversion rules only up to propositional equality. We illustrate the use of these models by several small examples taken from both formalised mathematics and program development. We also establish various syntactic properties of propositional equality including a proof of the undecidability of typing in extensional type theory and a correspondence between derivations in extensional type theory and terms in intensional type theory with extensional concepts added. Furthermore we settle affirmatively the hitherto open question of the independence of unicity of equality proofs in intensional type theory which implies that the addition of pattern matching to intensional type theory does not yield a conservative extension.