International audienceThe Early Toarcian Oceanic Anoxic Event (T-OAE), about 183 myr ago, was a global event of environmental and carbon cycle perturbations, which deeply affected both marine biota and carbonate production. Nevertheless, the long-term environmental conditions prevailing prior to the main phase of marine extinction and carbonate production crisis remain poorly understood. Here we present a similar to 8 myr-long record of Early Pliensbachian-Middle Toarcian environmental changes from the Lusitanian Basin, Portugal, in order to address the long-term paleoclimatic evolution that ultimately led to carbonate production and biotic crises during the T-OAE. Paleotemperature estimates derived from the oxygen isotope compositions of well-reserved brachiopod shells from two different sections reveal a pronounced similar to 5 degrees C cooling in the Late Pliensbachian (margaritatus-spinatum ammonite Zones boundary). This cooling event is followed by a marked similar to 7-10 degrees C seawater warming in the Early Toarcian that, after a second cooling event in the mid-polymorphum Zone, culminates during the T-OAE. Calcium carbonate (CaCO3) contents, the amount of nannofossil calcite and the mean size of the major pelagic carbonate producer Schizosphaerella, all largely covary with paleotemperatures, indicating a coupling between climatic conditions and both pelagic and neritic CaCO3 production. Furthermore, the cooling and warming episodes coincided with major marine regressions and transgressions, respectively, suggesting that the growth and decay of ice caps may have exerted a strong control on sea-level fluctuations throughout the studied time interval. This revised chronology of environmental changes shows important similarities with Neogene and Paleozoic episodes of deglacial black shale formation, and thus prompts the reevaluation of ice sheet dynamics as a possible agent of Mesozoic events of extinction and organic-rich sedimentation. (C) 2010 Elsevier B.V. All rights reserved

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Climbing performance relies to a great extent on the performance of the finger flexor muscles. Only a few studies investigated this performance in top class climbers and only one study compared gender-specific differences. This study investigated the climbing-specific finger flexor strength and endurance and related muscular oxygenation in 12 elite female and male climbers and 12 non-climbers. After the assessment of maximum voluntary finger flexor contraction (MVC), two isometric finger flexor endurance tests were performed at 40% MVC until exhaustion. A continuous isometric test was followed by an intermittent isometric test (10 s contraction, 3 s rest). Changes in oxygenation of finger flexor muscles were recorded using near infrared spectroscopy. MVC and strength-to-weight ratio were greater in climbers than non-climbers (P = 0.003; P < 0.001) and greater in men than women (P < 0.001; P = 0.002). Time to task failure for the intermittent test and the force-time integrals for the continuous and the intermittent test were also significantly greater in climbers (P = 0.030; P = 0.027; P = 0.005). During the intermittent test, re-oxygenation of the working muscles was faster in climbers (P < 0.05) without gender-specific differences. Close correlations were demonstrated between the best on-sight climbing performance and strength-to-weight ratio (r (2) = 0.946, P < 0.001) only in female climbers. The superior intermittent finger flexor endurance of climbers over non-climbers may be explained by the faster re-oxygenation of the finger flexor muscles during the short rest phases.

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