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Across the boreal forest of Canada, habitat disturbance is the ultimate cause of caribou (Rangifer tarandus caribou) declines. Habitat restoration is a focus of caribou recovery efforts, with a goal to finding ways to reduce predator use of disturbances, and caribou-predator encounters. One of the most pervasive disturbances within caribou ranges in Alberta, Canada are seismic lines cleared for energy exploration. Seismic lines facilitate predator movement, and although vegetation on some seismic lines is regenerating, it remains unknown whether vegetation regrowth is sufficient to alter predator response. We used Light Detection and Ranging (LiDAR) data, and GPS locations, to understand how vegetation and other attributes of seismic lines influence movements of two predators, wolves (Canis lupus) and grizzly bears (Ursus arctos). During winter, wolves moved towards seismic lines regardless of vegetation height, while during spring wolves moved towards seismic lines with higher vegetation. During summer, wolves moved towards seismic lines with lower vegetation and also moved faster near seismic lines with vegetation

The interaction between macromolecules is a fundamental aspect of most biological processes. The computational techniques used to study protein-protein and protein-nucleic acid interactions have evolved in the last few years because of the development of new algorithms that allow the a priori incorporation, in the docking process, of experimentally derived information, together with the possibility of accounting for the flexibility of the interacting molecules. Here we review the results and the evolution of the techniques used to study the interaction between metallo-proteins and DNA operators, all involved in the nickel and iron metabolism of pathogenic bacteria, focusing in particular on Helicobacter pylori (Hp). In the first part of the article we discuss the methods used to calculate the structure of complexes of proteins involved in the activation of the nickel-dependent enzyme urease. In the second part of the article, we concentrate on two applications of protein-DNA docking conducted on the transcription factors HpFur (ferric uptake regulator) and HpNikR (nickel regulator). In both cases we discuss the technical expedients used to take into account the conformational variability of the multi-domain proteins involved in the calculations.

This interview with Jean-Marc Manach – investigative reporter, specialist of surveillance and privacy protection on the Internet, and a wellknown French “hacker-journalist” – explores the issues of cyberconflict and cybersurveillance, focusing on the broad phenomenon of “piracy”. In doing so, the interview outlines the different definitions, framings and reconfigurations of those practices, enacted by network users, which have been labeled as “pirate” by different economic and political actors of the Internet value chain. Following Manach’s reflections, the interview provides a few benchmarks towards a critical perspective on “piracy” as an ensemble of situated practices which places us, perhaps for the best of our society, in the condition of being “all pirates” of today’s digital networks – engaged in the construction and sharing of cyberknowledge.

We evaluated whether coyote and wolf depredation management research in peer-reviewed journals differed from research in gray literature (e.g., conference proceedings, research reports). Regression analysis showed that journal published research was more likely to have used statistical analyses and have authors with academic affiliations. These results show that reliance on one literature type may lead to management and research decisions based on partial information. Focusing on journal literature may reduce the likelihood of encountering descriptive (i.e., non-statistical) analyses that could inform management and illuminate future avenues of research. For instance, half of the 76 descriptive experimental research findings we located, including 10 controlled experiments, were found only in gray literature documents. Our results highlight that canid depredation managers and researchers should utilize both journal and gray literature. [ABSTRACT FROM AUTHOR]

Integrin receptors mediate cell–cell interactions via the recognition of cell-adhesion glycoproteins, as well as via the interactions of cells with proteins of the extracellular matrix, and upon activation they transduce signals bi-directionally across the cell membrane. In the case of injury, infection, or inflammation, integrins of β2 and α4 families participate in the recruitment of leukocytes, a multi-step process initiated by the capturing of rolling leukocytes and terminated by their extravasation. In particular, α4β1 integrin is deeply involved in leukocyte firm adhesion preceding extravasation. Besides its well-known role in inflammatory diseases, α4β1 integrin is also involved in cancer, being expressed in various tumors and showing an important role in cancer formation and spreading. Hence, targeting this integrin represents an opportunity for the treatment of inflammatory disorders, some autoimmune diseases, and cancer. In this context, taking inspiration from the recognition motives of α4β1 integrin with its natural ligands FN and VCAM-1, we designed minimalist α/β hybrid peptide ligands, with our approach being associated with a retro strategy. These modifications are expected to improve the compounds' stability and bioavailability. As it turned out, some of the ligands were found to be antagonists, being able to inhibit the adhesion of integrin-expressing cells to plates coated with the natural ligands without inducing any conformational switch and any activation of intracellular signaling pathways. An original model structure of the receptor was generated using protein–protein docking to evaluate the bioactive conformations of the antagonists via molecular docking. Since the experimental structure of α4β1 integrin is still unknown, the simulations might also shed light on the interactions between the receptor and its native protein ligands. [ABSTRACT FROM AUTHOR]

Genetic diversity is theorized to decrease in populations closer to a species' range edge, where habitat may be suboptimal. Generalist species capable of long‐range dispersal may maintain sufficient gene flow to counteract this, though the presence of significant barriers to dispersal (e.g., large water bodies, human‐dominated landscapes) may still lead to, and exacerbate, the edge effect. We used microsatellite data for 2421 gray wolves (Canis lupus) from 24 subpopulations (groups) to model how allelic richness and expected heterozygosity varied with mainland–island position and two measures of range edge (latitude and distance from range center) across >7.3 million km2 of northern North America. We expected low genetic diversity both at high latitudes, due to harsh environmental conditions, and on islands, but no change in diversity with distance to the range center due to the species' exceptional dispersal ability and favorable conditions in far eastern and western habitats. We found that allelic richness and expected heterozygosity of island groups were measurably less than that of mainland groups, and that these differences increased with the island's distance to the species' range center in the study area. Our results demonstrate how multiple axes of geographic isolation (distance from range center and island habitation) can act synergistically to erode the genetic diversity of wide‐ranging terrestrial vertebrate populations despite the counteracting influence of long‐range dispersal ability. These findings emphasize how geographic isolation is a potential threat to the genetic diversity and viability of terrestrial vertebrate populations even among species capable of long‐range dispersal. [ABSTRACT FROM AUTHOR]

This article discusses some of the results of a five-year-long (and ongoing) investigation of alternative approaches to the design of internet services, based on decentralized network architectures. In particular, the paper focuses on the implications of this research for the study and the practice of internet governance, inasmuch as architectural changes affect the repartition of responsibilities between service providers, content producers, users and network operators; contribute to the shaping of user rights, of the ways to produce and enforce law; reconfigure the boundary between public and private uses of the internet as a global facility. I argue that delving into the tensions between the dwarfs and the giants of the Net – between different technical and organizational architectures, and their political consequences – helps us to disengage from what is often a predominantly institutional view of internet governance, and give due emphasis to its less visible, infrastructure-embedded arrangements, its materiality and its practice.

The creation and implementation of the Haute Autorité pour la diffusion des œuvres et la protection des droits sur Internet (High Authority for the diffusion of works and the protection of rights on the Internet, or Hadopi) is an occasion to observe the extent to which copyright is a performative system. The French legislator, to cope with the steady rise of downloads of copyright-protected digital content, attempts to fill “by law” the gap opened by the digital (r)evolution in the general anti-counterfeiting regime. This article follows the attempts to reconcile several conflicting dynamics – metrological frailties, difficulties of definition, diversity of infractions. Ultimately, a newly-created infraction, defined by unprecedented legal, material and moral components, provides a reference point allowing to restore – albeit tentatively – the authority of law on undefinable, unseizable objects, by defining as infringement the “failure to secure” one’s Internet connection.

InrS (internal nickel-responsive sensor) is a transcriptional regulator found in cyanobacteria that represses the transcription of the nickel exporter NrsD in the apo form and de-represses expression of the exporter upon Ni(II) binding. Although a crystal structure of apo-InrS from Synechocystis PCC 6803 has been reported, no structure of the protein with metal ions bound is available. Here we report the results of a computational study aimed to reconstruct the metal binding site by taking advantage of recent X-ray absorption spectroscopy (XAS) data and to envisage the structural rearrangements occurring upon Ni(II) binding. The modelled Ni(II) binding site shows a square planar geometry consistent with experimental data. The structural details of the conformational changes occurring upon metal binding are also discussed in the framework of trying to rationalize the different affinity of the apo- and holo-forms of the protein for DNA.