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This paper looks at reading in French immersion and how learning French is seen more as a skill rather than a social practice that could be examined through a more critical lens. Most of the teachers often teach students how to read but rarely will they discuss the role of French in Canadian society and how this is manifested in the texts they read and the world around them. This critical knowledge of how French and bilingualism are regarded in French immersion schools is lacking and brings several challenges to students inside and outside of the program. They learn how to read but can be quickly discouraged from using their French outside of school due to ideological assumptions that fail to recognize these students as bilingual, instead requiring cultural and native-like demonstrations of competence in the language in order to be accepted and allowed to speak.

The Saccharomyces cerevisiae protein Spo11 protein catalyzes the formation of double-strand breaks which initiate meiotic recombination in S. cerevisiae. This was gleaned from a comparison of the amino acid's mechanism of action with that of known type II topoisomerases as part of the study of genes encoding the A and B subunits of topoisomerase II from the archaeon Sulfolobus shibatae.

The graph parameter of pathwidth can be seen as a measure of the topological resemblance of a graph to a path. A popular definition of pathwidth is given in terms of node search, where we are given a system of tunnels (represented by a graph) that is contaminated by some infectious substance and we are looking for a search strategy that, at each step, either places a searcher on a vertex or removes a searcher from a vertex and where an edge is cleaned when both endpoints are simultaneously occupied by searchers. It was proved that the minimum number of searchers required for a successful cleaning strategy is equal to the pathwidth of the graph plus one. Two desired characteristics for a cleaning strategy are to be monotone (no recontamination occurs) and connected (clean territories always remain connected). Under these two demands, the number of searchers is equivalent to a variant of pathwidth called connected pathwidth. We prove that connected pathwidth is fixed parameter tractable; in particular we design a 2O(k2) \cdot n time algorithm that checks whether the connected pathwidth of G is at most k. This resolves an open question by Dereniowski, Osula, and Rz?azewski [Theoret. Comput. Sci., 794 (2019), pp. 85-100]. For our algorithm, we enrich the typical sequence technique that is able to deal with the connectivity demand. Typical sequences have been introduced by Bodlaender and Kloks [J. Algorithms, 21 (1996), pp. 358-402] for the design of linear parameterized algorithms for treewidth and pathwidth. While this technique has been later applied to other parameters, none of its advancements was able to deal with the connectivity demand, as it is a "global" demand that concerns an unbounded number of parts of the graph of unbounded size. The proposed extension is based on an encoding of the connectivity property that is quite versatile and may be adapted to deliver linear parameterized algorithms for the connected variants of other width parameters as well. An immediate consequence of our result is a 2O(k2) \cdot n time algorithm for the monotone and connected version of the edge search number. [ABSTRACT FROM AUTHOR]

The node‐search game against a lazy (or, respectively, agile) invisible robber has been introduced as a search‐game analogue of the treewidth parameter (and, respectively, pathwidth). In the connected variants of the above games, we additionally demand that, at each moment of the search, the clean territories are connected. The connected search game against an agile and invisible robber has been extensively examined. The monotone variant (where we demand that the clean territories are progressively increasing) of this game corresponds to the graph parameter of connected pathwidth. It is known that the price of connectivity to search for an agile robber is bounded by 2, that is, the connected pathwidth of a graph is at most twice (plus some constant) its pathwidth. We investigate the study of the connected search game against a lazy robber. A lazy robber moves only when the cops' strategy threatens the vertex that he currently occupies. We introduce two alternative graph‐theoretical formulations of this game, one in terms of connected tree‐decompositions and one in terms of (connected) layouts, leading to the graph parameter of connected treewidth. We observe that the connected treewidth parameter is closed under contractions and prove that for every k≥2, the set of contraction obstructions of the class of graphs with connected treewidth at most k is infinite. Our main result is a complete characterization of the obstruction set for k=2. We also show that, in contrast to the agile robber game, the price of connectivity is unbounded. [ABSTRACT FROM AUTHOR]

Bacteria–fungi interactions (BFIs) are essential in ecosystem functioning. These interactions are modulated not only by local nutritional conditions but also by the physicochemical constraints and 3D structure of the environmental niche. In soils, the unsaturated and complex nature of the substrate restricts the dispersal and activity of bacteria. Under unsaturated conditions, some bacteria engage with filamentous fungi in an interaction (fungal highways) in which they use fungal hyphae to disperse. Based on a previous experimental device to enrich pairs of organisms engaging in this interaction in soils, we present here the design and validation of a modified version of this sampling system constructed using additive printing. The 3D printed devices were tested using a novel application in which a target fungus, the common coprophilous fungus Coprinopsis cinerea , was used as bait to recruit and identify bacterial partners using its mycelium for dispersal. Bacteria of the genera Pseudomonas , Sphingobacterium and Stenotrophomonas were highly enriched in association with C. cinerea. Developing and producing these new easy-to-use tools to investigate how bacteria overcome dispersal limitations in cooperation with fungi is important to unravel the mechanisms by which BFIs affect processes at an ecosystem scale in soils and other unsaturated environments. [ABSTRACT FROM AUTHOR]