Clones in Graphs

Finding structural similarities in graph data, like social networks, is a far-ranging task in data mining and knowledge discovery. A (conceptually) simple reduction would be to compute the automorphism group of a graph. However, this approach is ineffective in data mining since real world data does not exhibit enough structural regularity. Here we step in with a novel approach based on mappings that preserve the maximal cliques. For this we exploit the well known correspondence between bipartite graphs and the data structure formal context $(G,M,I)$ from Formal Concept Analysis. From there we utilize the notion of clone items. The investigation of these is still an open problem to which we add new insights with this work. Furthermore, we produce a substantial experimental investigation of real world data. We conclude with demonstrating the generalization of clone items to permutations.Comment: 11 pages, 2 figures, 1 tabl

Efficient Enumeration of Bipartite Subgraphs in Graphs

Subgraph enumeration problems ask to output all subgraphs of an input graph that belongs to the specified graph class or satisfy the given constraint. These problems have been widely studied in theoretical computer science. As far, many efficient enumeration algorithms for the fundamental substructures such as spanning trees, cycles, and paths, have been developed. This paper addresses the enumeration problem of bipartite subgraphs. Even though bipartite graphs are quite fundamental and have numerous applications in both theory and application, its enumeration algorithms have not been intensively studied, to the best of our knowledge. We propose the first non-trivial algorithms for enumerating all bipartite subgraphs in a given graph. As the main results, we develop two efficient algorithms: the one enumerates all bipartite induced subgraphs of a graph with degeneracy $k$ in $O(k)$ time per solution. The other enumerates all bipartite subgraphs in $O(1)$ time per solution

Monalysin, a Novel ß-Pore-Forming Toxin from the Drosophila Pathogen Pseudomonas entomophila, Contributes to Host Intestinal Damage and Lethality

Pseudomonas entomophila is an entomopathogenic bacterium that infects and kills Drosophila. P. entomophila pathogenicity is linked to its ability to cause irreversible damages to the Drosophila gut, preventing epithelium renewal and repair. Here we report the identification of a novel pore-forming toxin (PFT), Monalysin, which contributes to the virulence of P. entomophila against Drosophila. Our data show that Monalysin requires N-terminal cleavage to become fully active, forms oligomers in vitro, and induces pore-formation in artificial lipid membranes. The prediction of the secondary structure of the membrane-spanning domain indicates that Monalysin is a PFT of the ß-type. The expression of Monalysin is regulated by both the GacS/GacA two-component system and the Pvf regulator, two signaling systems that control P. entomophila pathogenicity. In addition, AprA, a metallo-protease secreted by P. entomophila, can induce the rapid cleavage of pro-Monalysin into its active form. Reduced cell death is observed upon infection with a mutant deficient in Monalysin production showing that Monalysin plays a role in P. entomophila ability to induce intestinal cell damages, which is consistent with its activity as a PFT. Our study together with the well-established action of Bacillus thuringiensis Cry toxins suggests that production of PFTs is a common strategy of entomopathogens to disrupt insect gut homeostasis

Redução da estigmatização e da discriminação das pessoas idosas com transtornos mentais: uma declaração técnica de consenso

This technical consensus statement is jointly produced by the Old Age Psychiatry section of the World Psychiatric Association and the World Health Organization, with the collaboration of several NGOs and the participation of experts from different regions. It is intended to be a tool for (i) promoting debate at all levels on the stigmatization of older people with mental disorders; (ii) outlining the nature, causes and consequences of this stigmatization; and (iii) promoting and suggesting policies, programs and actions to combat this stigmatization.A Organização Mundial da Saúde (OMS) e a Seção de Psiquiatria da Pessoa Idosa da Associação Mundial de Psiquiatria (AMP), em colaboração com um grupo interdisciplinar de representantes das principais associações internacionais e organizações não-governamentais implicadas na saúde mental das pessoas idosas, publicaram três declarações técnicas de consenso sobre a psiquiatria da pessoa idosa (1), a organização dos cuidados em psiquiatria da pessoa idosa (2) e o ensino da psiquiatria da pessoa idosa (3). O Dia Mundial da Saúde 2001, cujo tema foi "Não à exclusão, sim aos cuidados", deu origem a uma nova reunião de consenso sobre o tema da estigmatização e discriminação das pessoas idosas com transtornos mentais. Essa nova reunião foi realizada em Lausanne nos dias 8 e 9 de outubro de 2001 e produziu uma declaração técnica de consenso. O texto inicial foi publicado pela OMS e AMP em inglês. Este artigo apresenta a versão em português desse documento

Frequency fluctuations in silicon nanoresonators

Frequency stability is key to performance of nanoresonators. This stability is thought to reach a limit with the resonator's ability to resolve thermally-induced vibrations. Although measurements and predictions of resonator stability usually disregard fluctuations in the mechanical frequency response, these fluctuations have recently attracted considerable theoretical interest. However, their existence is very difficult to demonstrate experimentally. Here, through a literature review, we show that all studies of frequency stability report values several orders of magnitude larger than the limit imposed by thermomechanical noise. We studied a monocrystalline silicon nanoresonator at room temperature, and found a similar discrepancy. We propose a new method to show this was due to the presence of frequency fluctuations, of unexpected level. The fluctuations were not due to the instrumentation system, or to any other of the known sources investigated. These results challenge our current understanding of frequency fluctuations and call for a change in practices

Contribution à l'étude des Ursidés pléistocènes des gorges de l'Ardèche et de leurs plateaux : les restes d'Ursus deningeri de la grotte des Fées, à Vallon-Pont-d'Arc (Ardèche)

The «grotte des Fées » is located in the Ibie valley, little tributary of the Ardèche river, near Vallon-Pont-d'Arc (Ardèche). This cave has yielded a partial skeleton with trunk, left shoulder blade, skull and mandibule, also an another skull, two hemimandibules and some post-cranial bones. As a whole there is a minimum of five bears adults and one cub. The attribution of these remains to Ursus deningeri is based on the dental characters.La grotte des Fées est située dans la vallée de l'Ibie, petit affluent de l'Ardèche, à Vallon-Pont-d'Arc (Ardèche), non loin de la célèbre grotte Chauvet. Elle a livré un squelette partiel avec tronc, omoplate gauche, crâne et mandibule, ainsi qu'un autre crâne, deux hémimandibules et quelques os du squelette post-crânien. Il y a des éléments d'au minimum cinq ours adultes et d'un ourson. L'attribution de ces restes à Ursus deningeri est essentiellement fondée sur les caractères dentaires.Ballesio Roland, Barth Philippe, Gély Bernard, Philippe Michel, Rosa Michel. Contribution à l'étude des Ursidés pléistocènes des gorges de l'Ardèche et de leurs plateaux : les restes d'Ursus deningeri de la grotte des Fées, à Vallon-Pont-d'Arc (Ardèche). In: Cahiers scientifiques du Muséum d'histoire naturelle de Lyon - Centre de conservation et d'étude des collections, tome 7, 2003. pp. 5-51