The Roles and Interactions of Symbiont, Host and Environment in Defining Coral Fitness

Background: Reef-building corals live in symbiosis with a diverse range of dinoflagellate algae (genus Symbiodinium) that differentially influence the fitness of the coral holobiont. The comparative role of symbiont type in holobiont fitness in relation to host genotype or the environment, however, is largely unknown. We addressed this knowledge gap by manipulating host-symbiont combinations and comparing growth, survival and thermal tolerance among the resultant holobionts in different environments.\ud Methodology/Principal Findings: Offspring of the coral, Acropora millepora, from two thermally contrasting locations, were experimentally infected with one of six Symbiodinium types, which spanned three phylogenetic clades (A, C and D), and then outplanted to the two parental field locations (central and southern inshore Great Barrier Reef, Australia). Growth and survival of juvenile corals were monitored for 31–35 weeks, after which their thermo-tolerance was experimentally assessed. Our results showed that: (1) Symbiodinium type was the most important predictor of holobiont fitness, as measured by growth, survival, and thermo-tolerance; (2) growth and survival, but not heat-tolerance, were also affected by local environmental conditions; and (3) host population had little to no effect on holobiont fitness. Furthermore, coral-algal associations were established with symbiont types belonging to clades A, C and D, but three out of four symbiont types belonging to clade C failed to establish a symbiosis. Associations with clade A had the lowest fitness and were unstable in the field. Lastly, Symbiodinium types C1 and D were found to be relatively thermo-tolerant, with type D conferring the highest tolerance in A. millepora.\ud Conclusions/Significance: These results highlight the complex interactions that occur between the coral host, the algal symbiont, and the environment to shape the fitness of the coral holobiont. An improved understanding of the factors affecting coral holobiont fitness will assist in predicting the responses of corals to global climate change

Financial disclosures of authors involved in spine research: an underestimated source of bias.

Item does not contain fulltextBACKGROUND: Reporting financial disclosures has become standard practice in both journal publications and during oral forum at scientific meetings. Despite this, the effect of reporting a financial disclosure of any member of an authorgroup, on the tone of the conclusion of an article has gained little attention. This study was performed to determine what effect reporting a financial disclosure has on the conclusion of an article. METHODS: A literature search for all articles on interspinous devices and cervical disc prostheses, published from January 1st, 2008 until December 1st, 2010 was performed. Financial disclosures were reported, as were funding by commercially active parties. The tone of the conclusions was graded as positive, neutral or negative. RESULTS: The odds ratio (OR) for a positive conclusion in cases where a financial disclosure was reported was 16.5 (95% CI: 4.7-58.1). Effect modification occurs with the presence of funding by a commercially active party. In cases where a financial disclosure was reported and funding was available for the study, the OR was 1.0 (95% CI: 0.08-12.6), whilst the OR was 33.3 (95%CI: 4.2-262.3) if funding was not provided. This discrepancy is mainly due to the large number of articles with a neutral/negative conclusion if the authors failed to report any financial disclosure and were not funded by a commercially active party. CONCLUSIONS: Reporting a financial disclosure is a potential source of bias. Authors with disclosed financial relationships less often publish articles with a neutral/negative conclusion. This source of bias should certainly be taken into account during the critical appraisal of articles, particularly when the quality of the literature is being assessed.1 juli 201

A study of the ZZ production cross-section in pppp collisions at s=7\sqrt{s} = 7 TeV using tau final states

A measurement of the inclusive Z → ττ cross-section in pp collisions at TeX is presented based on a dataset of 1.0 fb−1 collected by the LHCb detector. Candidates for Z → τ τ decays are identified through reconstructed final states with two muons, a muon and an electron, a muon and a hadron, or an electron and a hadron. The production cross-section for Z bosons, with invariant mass between 60 and 120 GeV/c 2, which decay to τ leptons with transverse momenta greater than 20 GeV/c and pseudorapidities between 2.0 and 4.5, is measured to be σ pp→Z→ττ = 71.4 ± 3.5 ± 2.8 ± 2.5 pb; the first uncertainty is statistical, the second is systematic, and the third is due to the uncertainty on the integrated luminosity. The ratio of the cross-sections for Z → τ τ to Z → μμ is determined to be 0.93 ± 0.09, where the uncertainty is the combination of statistical, systematic, and luminosity uncertainties of the two measurements