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Splicing factors have recently been shown to be involved in heterochromatin formation, but their role in controlling heterochromatin structure and function remains poorly understood. In this study, we identified a fission yeast homologue of human splicing factor RBM10, which has been linked to TARP syndrome. Overexpression of Rbm10 in fission yeast leads to strong global intron retention. Rbm10 also interacts with splicing factors in a pattern resembling that of human RBM10, suggesting that the function of Rbm10 as a splicing regulator is conserved. Surprisingly, our deep-sequencing data showed that deletion of Rbm10 caused only minor effect on genome-wide gene expression and splicing. However, the mutant displays severe heterochromatin defects. Further analyses confirmed that the heterochromatin defects in the mutant did not result from mis-splicing of heterochromatin factors. Our proteomic data revealed that Rbm10 associates with the histone deacetylase Clr6 complex and chromatin remodeling complexes known to be essential for heterochromatin silencing. Our work together with previous findings further suggests that different splicing subunits may play distinct roles in heterochromatin regulation.

We show that every continuous derivation of a countably dominated Fréchet GB-algebra A is spatial whenever A is additionally an AO-algebra. © Instytut Matematyczny PAN, 2015.

It is an open question whether every derivation of a Fréchet GB∗-algebra A[Τ] is continuous. We give an affirmative answer for the case where A[Τ] is a smooth Fréchet nuclear GB∗-algebra. Motivated by this result, we give examples of smooth Fréchet nuclear GB∗-algebras which are not pro-C∗-algebras. © 2015 Australian Mathematical Publishing Association Inc.

Generalized B*-algebras (shortly, GB*-algebras) are generalizations of C*-algebras and belong to the class of abstract unbounded operator algebras. These algebras have interesting applications in mathematical physics and this gives a strong impetus for studying them. To our knowledge, up to now, there is nothing in the literature about tensor products of GB*-algebras. For this reason, this paper is devoted to the investigation of this subject matter. © 2014 Elsevier Inc.

The term GW∗-algebra means a generalized W∗-algebra and corresponds to an unbounded generalization of a standard von Neumann algebra. It was introduced by the second named author in 1978 for developing the Tomita-Takesaki theory in algebras of unbounded operators. In this note we consider tensor products of unbounded operator algebras resulting in a GW∗-algebra. Existence and uniqueness of the GW∗-tensor product is encountered, while \properly W∗-infinite" GW∗-algebras are introduced and their structure is investigated. Copyright © 2014 Rocky Mountain Mathematics Consortium.

In this note, we present a statistical-physics framework for combinatorial auctions, i.e. multi-item auctions where bidders bid on combinations of items. The combinatorial problem is represented as a lattice-gas model, such that methods from the statistical physics of complex, disordered systems can be applied. In a minimal probabilistic setting, we find a phase transition from an easily solvable to a harder phase, where the solution space becomes clustered. In addition, the reformulation as a statistical-physics model allows the introduction of new and efficient message passing algorithms for single CA instances.

Survey Propagation is an algorithm designed for solving typical instances of random constraint satisfiability problems. It has been successfully tested on random 3-SAT and random $G(n,\frac{c}{n})$ graph 3-coloring, in the hard region of the parameter space. Here we provide a generic formalism which applies to a wide class of discrete Constraint Satisfaction Problems., 8 pages, 5 figures

In the recent past more and more attention has been dedicated to the development of a network approach. Unfortunately, in many cases efforts undertaken so far have chosen a static point of view neglecting the time-factor involved; or, if they paid attention to it, they were comparative-static at best. As a consequence, evolution of networks as a period-of-time-based phenomenon has not been explored as thoroughly as structures and conditions prevailing at a certain point of time. Furthermore, scholars so far have treated both strands of networks interorganizational and intraorganizational - separately, thus, more or less neglecting the interrelations existing between them. But it is exactly these interrelations that drive the dynamics of network phenomena. This article taking a truly dynamic perspective puts the emergence and evolution of networks into the context of the interrelations between intraorganizational and interorganizational networks. To achieve that, it identifies five effects which may help to explain the rise, prevalence and stabilization, as well as the demise of bilateral relationships and even of whole network-structures.

We analyse the eigenvalue structure of the replicated transfer matrix of one-dimensional disordered Ising models. In the limit of $n \rightarrow 0$ replicas, an infinite sequence of transfer matrices is found, each corresponding to a different irreducible representation (labelled by a positive integer $\rho$) of the permutation group. We show that the free energy can be calculated from the replica symmetric subspace ($\rho =0$). The other ``replica symmetry broken'' representations ($\rho \ne 0$) are physically meaningful since their largest eigenvalues $\lambda^{(\rho )}$ control the disorder--averaged moments $\ll( \langle S_i S_j \rangle - \langle S_i \rangle \langle S_j \rangle )^\rho \gg \propto (\lambda^{(\rho )}) ^{|i-j|}$ of the connected two-points correlations., Comment: 4 pages, REVTeX, no figures

Combinatorial auctions are formulated as frustrated lattice gases on sparse random graphs, allowing the determination of the optimal revenue by methods of statistical physics. Transitions between computationally easy and hard regimes are found and interpreted in terms of the geometric structure of the space of solutions. We introduce an iterative algorithm to solve intermediate and large instances, and discuss competing states of optimal revenue and maximal number of satisfied bidders. The algorithm can be generalized to the hard phase and to more sophisticated auction protocols., 4 pages, 4 figures, minor changes, references added. To appear on PRL