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Permeability controls energy and matter fluxes in deep‐sea hydrothermal systems fueling a 'deep biosphere' of microorganisms. Here, we indirectly measure changes in sub‐seafloor crustal permeability, based on the tidal response of high‐temperature hydrothermal vents at the East Pacific Rise 9°50'N preceding the last phase of volcanic eruptions during 2005–2006. Ten months before the last phase of the eruptions, permeability decreased, first rapidly, and then steadily as the stress built up, until hydrothermal flow stopped altogether ∼2 weeks prior to the January 2006 eruption phase. This trend was interrupted by abrupt permeability increases, attributable to dike injection during last phase of the eruptions, which released crustal stress, allowing hydrothermal flow to resume. These observations and models suggest that abrupt changes in crustal permeability caused by magmatic intrusion and volcanic eruption can control first‐order hydrothermal circulation processes. This methodology has the potential to aid eruption forecasting along the global mid‐ocean ridge network. Plain Language Summary: Permeability governs how fluids such as water and melt flow beneath the seafloor, and is influenced by diverse magmatic, volcanic, and tectonic forces as new oceanic crust is formed and altered over time. Despite being a master variable controlling the fluxes of energy and matter in deep‐sea hydrothermal systems, permeability remains a poorly constrained hydrologic parameter of the oceanic crust. Here, we indirectly measure changes in crustal permeability for the first time, using the tidal response of high‐temperature hydrothermal vents on the East Pacific Rise at 9°50'N preceding the last phase of volcanic eruptions in 2005–2006. We show that abrupt changes in crustal permeability caused by magmatic intrusion and volcanic eruption can control first‐order hydrothermal circulation processes. Key Points: Hydrothermal vent fluid temperature data modeled with ocean tides reveal permeability changes associated with seafloor volcanic eruptionsChanges in crustal permeability caused by magmatic intrusion and volcanic eruption control first‐order hydrothermal circulation processesThis methodology expands the potential of forecasting seafloor eruptions along the global mid‐ocean ridge network [ABSTRACT FROM AUTHOR]

Although the tambaqui (Colossoma macropomum) is the most cultivated native fish species in Brazil, estimated breeding values for growth traits are rarely used for selection of superior individuals in commercial fingerling production. This study aimed to estimate the (co)variance components of growth traits. Body weight, length and width of 2500 tambaqui were determined at tagging and at 6 and 12 months after tagging in a commercial breeding programme in Brazil. Heritability estimates were low for traits measured at tagging (0.10 to 0.19) and moderate to high for traits measured at 6 and 12 months (0.23 to 0.81). Common full-sib effects were high at tagging (>73%), low at 6 months and negligible at 12 months. Positive genetic correlations were found among growth traits at 12 months (0.84 to 0.99) and between growth traits at 6 and 12 months (0.80 to 0.92). These results show that animal selection can be performed at 6 months after tagging. Expected genetic gains for growth traits ranged from 8% to 31%. A simulation of the sex ratio was performed, as individuals did not reach sexual maturity during the experimental period. Because of the sexual dimorphism, more accurate heritability estimates were obtained when considering the female proportion to be 90% in the high-weight group. The findings indicate that it is possible to obtain considerable genetic gains in growth by selecting for growth traits. The development of a tool to determine the sex of animals at early stages can improve the response to selection in tambaqui. [ABSTRACT FROM AUTHOR]

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While processes associated with initiation and maintenance of oceanic detachment faults are becoming better constrained, much less is known about the tectonic and magmatic conditions that lead to fault abandonment. Here we present results from near‐bottom investigations using the submersible Alvin and autonomous underwater vehicle Sentry at a recently extinct detachment fault near 13°48′N, Mid‐Atlantic Ridge, that allow documentation of the final stages of fault activity and magmatism. Seafloor imagery, sampling, and near‐bottom magnetic data show that the detachment footwall is intersected by an ~850 m‐wide volcanic outcrop including pillow lavas. Saturation pressures in these vesicular basalts, based on dissolved H2O and CO2, are less than their collection pressures, which could be explained by eruption at a shallower level than their present depth. Sub‐bottom profiles reveal that sediment thickness, a loose proxy for seafloor age, is ~2 m greater on top of the volcanic terrain than on the footwall adjacent to the hanging‐wall cutoff. This difference could be explained by current‐driven erosion in the axial valley or by continued slip after volcanic emplacement, on either a newly formed or pre‐existing fault. Since current speeds near the footwall are unlikely to be sufficient to cause significant erosion, we favor the hypothesis that detachment slip continued after the episode of magmatism, consistent with growing evidence that oceanic detachments can continue to slip despite hosting magmatic intrusions. Key Points: Autonomous underwater vehicle and submersible surveys carried out over inactive detachment fault on Mid‐Atlantic RidgeSediment thickness and volatile content of lavas were used to track tectonic activitySeafloor observations suggest that slip continued after a volcanic intrusion into detachment fault footwall [ABSTRACT FROM AUTHOR]

Objective In two laboratories (Departments of Pathology, Copenhagen University Hospitals of Herlev and Hvidovre), we compared cobas and Hybrid Capture 2 (HC2) human papillomavirus (HPV) assays using SurePath® samples from women with atypical squamous cells of undetermined significance (ASCUS) at ≥30 years and women after treatment of cervical intraepithelial neoplasia (CIN). Methods Samples from 566 women with ASCUS and 411 women after treatment were routinely tested with HC2 and, thereafter, with cobas. Histological outcomes were retrieved from the Danish Pathology Data Base. We calculated the overall agreement between the assays, and compared their sensitivity and specificity for ≥CIN2. Results In women with ASCUS, HC2 and cobas testing results were similar in the two laboratories. The overall agreement was 91% (95% CI, 88-93). After CIN treatment, the overall agreement was 87% (95% CI, 82-91) at Herlev and 88% (95% CI, 82-92) at Hvidovre. There were no significant differences in the sensitivity for ≥CIN2 between the two tests [Herlev, 98% (95% CI, 89-100) for HC2 versus 94% (95% CI, 82-99) for cobas; Hvidovre, 97% (95% CI, 83-100) for HC2 versus 100% (95% CI, 88-100) for cobas]. The differences were also not significant for specificity. Conclusions In women with the studied well-defined clinical indications for HPV testing, cobas and HC2 performed similarly in terms of the detection of HPV and ≥CIN2. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Examines the biogeography and ecological setting of hydrothermal vents in Indian Ocean. Analysis of the invertebral-bacterial symbioses; Formation of asymmetric assembly rules Contribution to the biography of chemosynthetic faunas.