Alluvial record of an early Eocene hyperthermal within the Castissent Formation, the Pyrenees, Spain

The late Palaeocene to the middle Eocene (57.5 to 46.5 Ma) recorded a total of 39 hyperthermals – periods of rapid global warming documented by prominent negative carbon isotope excursions (CIEs) as well as peaks in iron content – have been recognized in marine cores. Documenting how the Earth system responded to rapid climatic shifts during hyperthermals provides fundamental information to constrain climatic models. However, while hyperthermals have been well documented in the marine sedimentary record, only a few have been recognized and described in continental deposits, thereby limiting our ability to understand the effect and record of global warming on terrestrial systems. Hyperthermals in the continental record could be a powerful correlation tool to help connect marine and continental deposits, addressing issues of environmental signal propagation from land to sea. In this study, we generate new stable carbon isotope data (δ13C values) across the well-exposed and time-constrained fluvial sedimentary succession of the early Eocene Castissent Formation in the south central Pyrenees (Spain). The δ13C values of pedogenic carbonate reveal – similarly to the global records – stepped CIEs, culminating in a minimum δ13C value that we correlate with the hyperthermal event “U” at ca. 50 Ma. This general trend towards more negative values is most probably linked to higher primary productivity leading to an overall higher respiration of soil organic matter during these climatic events. The relative enrichment in immobile elements (Zr, Ti, Al) and higher estimates of mean annual precipitation together with the occurrence of small iron oxide and iron hydroxide nodules during the CIEs suggest intensification of chemical weathering and/or longer exposure of soils in a highly seasonal climate. The results show that even relatively small-scale hyperthermals compared with their prominent counterparts, such as PETM, ETM2, and ETM3, can leave a recognizable signature in the terrestrial stratigraphic record, providing insights into the dynamics of the carbon cycle in continental environments during these events

Corporate governance compliance and disclosure in the banking sector: using data from Japan

Using regression model this study investigates which characteristics of a bank is associated with the extent of corporate governance disclosure in Japan. The findings suggest that on average 8 banks out of a sample of 46 disclose optimal corporate governance information. The regression model results reveal in general that non-executive directors, cross-ownership, capital adequacy ratio and type of auditors are associated with the extent of corporate governance disclosure. Of these four variables, non-executive directors have a more significant impact on the extent of disclosure contrary to total assets and audit firms of banks in the context of Japan. The findings of this paper are relevant for corporate regulators, professional associations and developers of corporate governance code when designing or updating corporate governance code

A Search for Selectrons and Squarks at HERA

Data from electron-proton collisions at a center-of-mass energy of 300 GeV are used for a search for selectrons and squarks within the framework of the minimal supersymmetric model. The decays of selectrons and squarks into the lightest supersymmetric particle lead to final states with an electron and hadrons accompanied by large missing energy and transverse momentum. No signal is found and new bounds on the existence of these particles are derived. At 95% confidence level the excluded region extends to 65 GeV for selectron and squark masses, and to 40 GeV for the mass of the lightest supersymmetric particle.Comment: 13 pages, latex, 6 Figure

Pedogenic carbonate nodules as soil time archives: challenges and investigations related to OSL dating

Pedogenic carbonate nodules have been observed in the Far North region of Cameroon. They have been interpreted as Vertisol relic components inherited from the African Humid Period (AHP), however their processes of formation remain poorly constrained. Here we explore the possibility of targeting the minerals trapped within such nodules, which represent a residual soil fraction, to date the deposition time of the soil parent material using optically stimulated luminescence (OSL). As the trapped minerals have a complex history, related to pedogenesis and sedimentary processes since their deposition, it was necessary to identify a suitable mineral population. To achieve this, a nodule collected at the surface was investigated in order to compare the OSL signals from feldspar minerals from within its external and internal parts. The resultant luminescence data were then compared with minerals trapped in a buried nodule, with the scatter in OSL signals between the different populations indicating potential partial bleaching of grains and/or pedoturbation processes. Our results show that the minerals from the internal part of the nodule are appropriate for OSL dating. Furthermore, the environmental dose rate has changed through time following carbonate precipitation and the radionuclide decay series may be in disequilibrium. Because of its solubility, the 238U-series is particularly affected, and when a complete absence of 234L1 daughters is assumed, our calculations show a maximum and significant decrease of 20% in the environmental dose rate compared to secular equilibrium. Finally, changing the time of carbonate nodule precipitation results in a maximum OSL age range of 121 a (from 15 to 27 ka) for the deposition of the soil parent material. Despite this relatively high uncertainty, these ages suggest that the deposition occurred before the AHP. Consequently, if their formation time is well constrained from independent methods, the pedogenic carbonate nodules can be exploited as valuable time archives, providing temporal information on soil parent material deposition and thus a maximum age for the onset of pedogenesis. (C) 2016 Elsevier B.V. All rights reserved

Fungal hyphae, spores and bacteria from the Upper Devonian of the Rocky Mountains, Canada: how old are they? Preliminary study

Poster et Abstract, p 34-35info:eu-repo/semantics/nonPublishe

Fungal hyphae, spores and bacteria from the Lower Cretaceous of Central Italy: how old are they? Preliminary study

Poster et Abstract, p.46-47info:eu-repo/semantics/nonPublishe

Corporate governance compliance and disclosure in the banking sector: using data from Japan

Using regression model this study investigates which characteristics of a bank is associated with the extent of corporate governance disclosure in Japan. The findings suggest that on average 8 banks out of a sample of 46 disclose optimal corporate governance information. The regression model results reveal in general that non-executive directors, cross-ownership, capital adequacy ratio and type of auditors are associated with the extent of corporate governance disclosure. Of these four variables, non-executive directors have a more significant impact on the extent of disclosure contrary to total assets and audit firms of banks in the context of Japan. The findings of this paper are relevant for corporate regulators, professional associations and developers of corporate governance code when designing or updating corporate governance code