Random Generation and Enumeration of Accessible Determinisitic Real-time Pushdown Automata

This papers presents a general framework for the uniform random generation of deterministic real-time accessible pushdown automata. A polynomial time algorithm to randomly generate a pushdown automaton having a fixed stack operations total size is proposed. The influence of the accepting condition (empty stack, final state) on the reachability of the generated automata is investigated.Comment: Frank Drewes. CIAA 2015, Aug 2015, Umea, Sweden. Springer, 9223, pp.12, 2015, Implementation and Application of Automata - 20th International Conferenc

On the Uniform Random Generation of Determinisitic Partially Ordered Automata using Monte Carlo Techniques

Partially ordered automata are finite automata admitting no simple loops of length greater than or equal to 2. In this paper we show how to randomly and uniformly generate deterministic accessible partially ordered automata using Monte-Carlo techniques

Evolution of testicular architecture in the Drosophilidae: A role for sperm length

Background: Evolutionary biologists have so far largely treated the testis as a black box with a certain size, a matching resource demand and a resulting sperm output. A better understanding of the way that the testis responds to selection may come from recent developments in theoretical biology aimed at understanding the factors that influence the evolution of tissue architecture (i.e. the logical organisation of a tissue). Here we perform a comparative analysis of aspects of testicular architecture of the fruit fly family Drosophilidae. Specifically, we collect published information on the number of first (or primary) spermatocytes in spermatogenesis, which allows to infer an important aspect of testicular architecture. Results: We show that testicular architecture is much more variable (both within and between species) than is generally appreciated. Moreover, the number of first spermatocytes is strongly correlated to the sperm length, which is inversely related to the sperm production, and thus the workload of the testis. Conclusion: Our study clearly documents that tissue architecture can evolve, and that in the Drosophilidae it may do so in response to sexual selection. We conclude that the testis of the Drosophilidae is a promising model organ to test recent models of tissue architecture

Glial activation in white matter following ischemia in the neonatal P7 rat brain

This study examines cell death and proliferation in the white matter after neonatal stroke. In post-natal day 7 injured rat, there was a marked reduction in myelin basic protein (MBP) immunostaining mainly corresponding to numerous pyknotic immature oligodendrocytes and TUNEL-positive astrocytes in the ipsilateral external capsule. In contrast, a substantial restoration of MBP, as indicated by the MBP ratio of left-toright, occurred in the cingulum at 48 (1.27 +- 0.12) and 72 (1.30 +- 0.18, p<0.05) hours of recovery as compared to age-matched controls (1.03 +- 0.14). Ki-67 immunostaining revealed a first peak of newly-generated cells in the dorsolateral hippocampal subventricular zone and cingulum at 72 hours after reperfusion. Double immunofluorescence revealed that most of the Ki-67-positive cells were astrocytes at 48 hours and NG2 pre-oligodendrocytes at 72 hours of recovery. Microglia infiltration occurs over several days in the cingulum and a huge quantity of macrophages reached the subcortical white matter where they engulfed immature oligodendrocytes. The overall results suggest that the persistent activation of microglia involves a chronic component of immunoinflammation, which overwhelms repair processes and contributes to cystic growth in the developing brain.Comment: 30 page

On the Uniform Random Generation of Determinisitic Partially Ordered Automata using Monte Carlo Techniques

Partially ordered automata are finite automata admitting no simple loops of length greater than or equal to 2. In this paper we show how to randomly and uniformly generate deterministic accessible partially ordered automata using Monte-Carlo techniques

Accumulation et effets des éléments métalliques sur les populations végétales spontanées de trois crassiers métallurgiques : peut-on utiliser les plantes comme bioindicateurs ?

National audienceThe actual risk of metals doesn't depend on their total concentrations, but rather on their bioavailability and own toxicity, it is important to get suitable tools for evaluating bioavailability and ecological effects of metals in situ. In this context, characterization of bioindicators of soil quality is a challenging issue. In this work, we hypothesized that plants colonizing metal-contaminated soils could be an efficient tool to assess both the bioavailability of metals, and their effect on local ecosystem. To check this hypothesis, we studied spontaneous vegetation colonizing three metallurgical landfills characterised by different total and extractible heavy metals fractions (Table 1), both in terms of metal accumulation in leaves and of phytosociological associations. Results (Tables 2 and 3) showed that for two out of the three studied sites, leaf metals in native plants were closely comparable to normal concentrations found in plants growing in uncontaminated soil, while for the third site average levels in Cr, Cu, Ni, Pb and Zn were significantly higher. Thus, measurements of leaf metals clearly discriminated the studied sites, with respect to actual metal phytoavailability. Botanical survey of the three study sites showed that the vegetation was quite normal, with common species, their associations were unusual and, among the four major plant groups we identified, three of them had never been described. This suggested that metallurgical soils had an effect on the structure of plant communities independently from metal bioavailability. These overall results show that beside soil analyses, plants can provide additional indications regarding both the effects and potential mobility of pollutants.Il est aujourd'hui important de disposer d'outils efficaces pour évaluer la biodisponibilité et les effets écologiques des éléments métalliques des sols pollués. Dans ce contexte, la caractérisation de bioindicateurs de la qualité des sols représente un enjeu important. Pour répondre à cet objectif, nous proposons d'étudier l'accumulation foliaire et les associations végétales de la flore spontanée. Trois sites contaminés ont été étudiés. Sur deux d'entre eux, les concentrations métalliques (Cr, Cu, Ni, Pb et Zn) mesurées dans les plantes sont comparables à celles de la végétation se développant en milieu naturel non contaminé. Pour le troisième, ces concentrations sont significativement supérieures. De plus, ces analyses ont permis de différencier clairement les sites au regard de la phytodisponibilité des métaux. L'étude botanique des sites contaminés indique que si la végétation paraît normale, avec beaucoup d'espèces communes, les quatre associations végétales identifiées sont néanmoins particulières, voire inédites pour trois d'entre elles. Cette observation suggère que le substrat, indépendamment de la mobilité des métaux, a un effet sur la structure des communautés végétales. L'ensemble de ces résultats montre que l'analyse classique de sol, peut être avantageusement complétée par des analyses de la végétation au regard de l'estimation de la biodisponibilité des éléments métalliques et de leurs effets

Une enquête sur l’éthique professionnelle des enseignants du collégial québécois : caractéristiques, points de repère et stratégies utilisés pour traiter de préoccupations éthiques

&nbsp; Some results of a survey on professional ethics conducted among francophone college teachers in Quebec are compared with a review of the literature and the results of focus groups previously held on the subject. The justification reasons behind the ethical nature of certain professional concerns, along with the guidelines and the resolution strategies used to address those concerns, are found to be similar. These justifications relate primarily to situations where there is a conflict of conscience, a conflict of values or consequences on others, particularly students; the calling into question of professional integrity stands out as a particular justification not mentioned in earlier studies. The guidelines to deal with dilemmas are also similar: institutional normative texts and values deemed relevant by the teachers come first. The results show a good balance between the use of these two types of guidelines (external and internal) by teachers. The main strategies applied by teachers for resolving dilemmas are peer discussions and personal reflection.Certains résultats d’une enquête sur l’éthique professionnelle menée auprès d’enseignants des collèges québécois sont comparés avec une recension des écrits sur la question et les résultats d’entrevues réalisées préalablement dans des groupes de discussion. Tant au sujet des indices ou des raisons démontrant le caractère éthique de certaines préoccupations professionnelles que sur les points de repère et les stratégies de résolution privilégiés, une grande convergence est observée entre les répondants à l’enquête, les participants aux groupes de discussion et les constats qui émergent de la recension des écrits. Dans l’ensemble, les raisons évoquées par les enseignants pour affirmer le caractère éthique de certaines préoccupations professionnelles renvoien surtout aux cas de conscience et aux conflits de valeurs ainsi qu’à l’anticipation de conséquences sur autrui, particulièrement vis-à-vis des étudiants. Seule la raison « mise en cause de l’intégrité professionnelle » n’avait pas été relevée dans les études antérieures. Les points de repère principaux auxquels se fient les enseignants sont les textes normatifs adoptés par les établissements et leurs valeurs et principes personnels. Ces résultats suggèrent qu’il existe un équilibre, chez les enseignants, dans l’utilisation de ces deux types de repères, externes et internes. Enfin, les principales stratégies de résolution des dilemmes éthiques déployées par les enseignants consistent essentiellement en la discussion entre pairs et la réflexion personnelle

Cyclic olefin homopolymer-based microfluidics for protein crystallization and in situ X-ray diffraction

A cyclic olefin homopolymer-based microfluidics system has been established for protein crystallization and in situ X-ray diffraction