Co-evolutionary dynamics of collective action with signaling for a quorum

Collective signaling for a quorum is found in a wide range of organisms that face collective action problems whose successful solution requires the participation of some quorum of the individuals present. These range from humans, to social insects, to bacteria. The mechanisms involved, the quorum required, and the size of the group may vary. Here we address the general question of the evolution of collective signaling at a high level of abstraction. We investigate the evolutionary dynamics of a population engaging in a signaling N-person game theoretic model. Parameter settings allow for loners and cheaters, and for costly or costless signals. We find a rich dynamics, showing how natural selection, operating on a population of individuals endowed with the simplest strategies, is able to evolve a costly signaling system that allows individuals to respond appropriately to different states of Nature. Signaling robustly promotes cooperative collective action, in particular when coordinated action is most needed and difficult to achieve. Two different signaling systems may emerge depending on Nature's most prevalent states.Funding: This research was supported by FEDER through POFC - COMPETE, FCT-Portugal through grants SFRH/BD/86465/2012, PTDC/MAT/122897/2010, EXPL/EEI-SII/2556/2013, and by multi-annual funding of CMAF-UL, CBMA-UM and INESC-ID (under the projects PEst-OE/BIA/UI4050/2014 and UID/CEC/50021/2013) provided by FCT-Portugal, and by Fundacao Calouste Gulbenkian through the "Stimulus to Research" program for young researchers. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.info:eu-repo/semantics/publishedVersio

Intracameral bevacizumab and mitomycin C Trabeculectomy for eyes with neovascular glaucoma: a case series

The purpose of this study was to describe the surgical outcomes and safety of intracameral bevacizumab during trabeculectomy in eyes with neovascular glaucoma. Pilot study included four eyes (four patients) with refractory neovascular glaucoma submitted to fornix-based trabeculectomy with adjunctive use of bevacizumab in the anterior chamber during the procedure. Patients were previously treated with panretinal photocoagulation as standard therapy. Variables evaluated were intraocular pressure, bleb appearance, iris neovascularization, intraoperative/postoperative complications, and visual outcomes. No intraoperative complication was observed. The mean follow-up period was 12.75 (range, 12–15 months). All eyes showed significant intraocular pressure control postoperatively. Iris neovascularization reduced significantly within 1 month after surgery. Mild anterior chamber inflammation was observed during follow-up in all eyes. No significant postoperative complication was observed, and no patient presented visual acuity deterioration. Intracameral bevacizumab may be used as an adjunctive therapy during trabeculectomy in eyes with neovascular glaucoma

The program for biodiversity research in Brazil: The role of regional networks for biodiversity knowledge, dissemination, and conservation

The Program for Biodiversity Research (PPBio) is an innovative program designed to integrate all biodiversity research stakeholders. Operating since 2004, it has installed long-term ecological research sites throughout Brazil and its logic has been applied in some other southern-hemisphere countries. The program supports all aspects of research necessary to understand biodiversity and the processes that affect it. There are presently 161 sampling sites (see some of them at Supplementary Appendix), most of which use a standardized methodology that allows comparisons across biomes and through time. To date, there are about 1200 publications associated with PPBio that cover topics ranging from natural history to genetics and species distributions. Most of the field data and metadata are available through PPBio web sites or DataONE. Metadata is available for researchers that intend to explore the different faces of Brazilian biodiversity spatio-temporal variation, as well as for managers intending to improve conservation strategies. The Program also fostered, directly and indirectly, local technical capacity building, and supported the training of hundreds of undergraduate and graduate students. The main challenge is maintaining the long-term funding necessary to understand biodiversity patterns and processes under pressure from global environmental changes