The role of nominating committees and director reputation in shaping the labor market for directors: an empirical assessment

Research Question/Issue: Do the presence and independence of nominating committees within boards of directors affect the extent of rewards and sanctions provided by the labor market to directors with a reputation for being active in monitoring management? Research Findings/Insights: Results drawn from a longitudinal sample of directors sitting on the board of 200 public French firms suggest that the stronger a director's reputation for being active in increasing control over management, the larger the number of his/her subsequent appointments to (1) boards with a nominating committee, (2) to boards with a nominating committee which excludes the CEO and (3) to boards with a nominating committee dominated by non-executive directors. In contrast, we found that a director's reputation of being active in increasing control over management does not impact the number of his/her subsequent appointments (1) to boards without a nominating committee, (2) to boards with a nominating committee which includes the CEO and (3) to boards with a nominating committee dominated by executive directors. Theoretical/Academic Implications: This study shows that the outcome of the power struggle between the CEO and incumbent directors during the candidate selection process determines the profile of directors who will ultimately obtain the board appointment. On the one hand, independent nominating committees are likely to reduce the influence of CEOs over the process of a director's appointment, and therefore are likely to increase the recruitment of directors with reputations for being active in exercising control over managers. On the other hand, nonexistence of nominating committees or presence of weak nominating committees under the influence of the CEO decouple directors' reputations for being active in controlling management from the likelihood of obtaining new appointments. Practitioner/Policy Implications: This study offers insights to policy makers interested in increasing the efficiency of the labor market for directors. More specifically, it highlights the conditions under which directors with a reputation of being active in increasing control over management are likely to be rewarded by the labor market for directors. These conditions include (1) the creation of a nominating committee; (2) exclusion of the CEO from this committee and (3) domination of this committee by outside directors

Modeling denitrification in aquatic sediments

Author Posting. © The Author(s), 2008. This is the author's version of the work. It is posted here by permission of Springer for personal use, not for redistribution. The definitive version was published in Biogeochemistry 93 (2009): 159-178, doi:10.1007/s10533-008-9270-z.Sediment denitrification is a major pathway of fixed nitrogen loss from aquatic systems. Due to technical difficulties in measuring this process and its spatial and temporal variability, estimates of local, regional and global denitrification have to rely on a combination of measurements and models. Here we review approaches to describing denitrification in aquatic sediments, ranging from mechanistic diagenetic models to empirical parameterizations of nitrogen fluxes across the sediment-water interface. We also present a compilation of denitrification measurements and ancillary data for different aquatic systems, ranging from freshwater to marine. Based on this data compilation we reevaluate published parameterizations of denitrification. We recommend that future models of denitrification use (1) a combination of mechanistic diagenetic models and measurements where bottom waters are temporally hypoxic or anoxic, and (2) the much simpler correlations between denitrification and sediment oxygen consumption for oxic bottom waters. For our data set, inclusion of bottom water oxygen and nitrate concentrations in a multivariate regression did not improve the statistical fit.Financial support for AEG to work on the manuscript came from NSF NSF-DEB-0423565. KF, DB and DDT acknowledge support from NOAA CHRP grant NA07NOS4780191

Lung resistance-related protein as a predictor of clinical outcome in advanced testicular germ-cell tumours

This study was undertaken to investigate the expression and predictive value for outcome of multidrug resistance-associated (MDR) proteins P-glycoprotein (Pgp), MRP1, BCRP, and LRP, in advanced testicular germ-cell tumours (TGCT). Paraffin-embedded sections from 56 previously untreated patients with metastatic TGCT were immunostained for Pgp, MRP1, BCRP, and LRP. All patients received platinum-based chemotherapy after orchidectomy. Immunostaining was related to clinicopathological parameters, response to chemotherapy, and outcome. Strong and intermediate expressions of the different MDR-related proteins were: 27 and 41% (Pgp), 54 and 37% (MRP1), 86 and 7% (BCRP), and 14 and 29% (LRP). P-glycoprotein and MRP1 associated, respectively, to low AFP (P=0.026) and high LDH levels (P=0.014), whereas LRP expression associated with high beta-hCG levels (P=0.003) and stage IV tumours (P=0.029). No correlation was found between Pgp, MRP1, and BCRP expression and response to chemotherapy and survival. In contrast, patients with LRP-positive tumours (strong or intermediate expression) had shorter progression-free (P=0.0006) and overall survival (P=0.0116) than LRP-negative patients, even after individual log-rank adjustments by statistically associated variables. Our data suggest that a positive LRP immunostaining at the time of diagnosis in metastatic TGCT is associated with an adverse clinical outcome

Oxygen dynamics in shelf seas sediments incorporating seasonal variability

Shelf sediments play a vital role in global biogeochemical cycling and are particularly important areas of oxygen consumption and carbon mineralisation. Total benthic oxygen uptake, the sum of diffusive and faunal mediated uptake, is a robust proxy to quantify carbon mineralisation. However, oxygen uptake rates are dynamic, due to the diagenetic processes within the sediment, and can be spatially and temporally variable. Four benthic sites in the Celtic Sea, encompassing gradients of cohesive to permeable sediments, were sampled over four cruises to capture seasonal and spatial changes in oxygen dynamics. Total oxygen uptake (TOU) rates were measured through a suite of incubation experiments and oxygen microelectrode profiles were taken across all four benthic sites to provide the oxygen penetration depth and diffusive oxygen uptake (DOU) rates. The difference between TOU and DOU allowed for quantification of the fauna mediated oxygen uptake and diffusive uptake. High resolution measurements showed clear seasonal and spatial trends, with higher oxygen uptake rates measured in cohesive sediments compared to the permeable sediment. The significant differences in oxygen dynamics between the sediment types were consistent between seasons, with increasing oxygen consumption during and after the phytoplankton bloom. Carbon mineralisation in shelf sediments is strongly influenced by sediment type and seasonality

Aerobic denitrification in permeable Wadden Sea sediments

Permeable or sandy sediments cover the majority of the seafloor on continental shelves worldwide, but little is known about their role in the coastal nitrogen cycle. We investigated the rates and controls of nitrogen loss at a sand flat (Janssand) in the central German Wadden Sea using multiple experimental approaches, including the nitrogen isotope pairing technique in intact core incubations, slurry incubations, a flow-through stirred retention reactor and microsensor measurements. Results indicate that permeable Janssand sediments are characterized by some of the highest potential denitrification rates (≥0.19 mmol N m−2 h−1) in the marine environment. Moreover, several lines of evidence showed that denitrification occurred under oxic conditions. In intact cores, microsensor measurements showed that the zones of nitrate/nitrite and O2 consumption overlapped. In slurry incubations conducted with 15NO3− enrichment in gas-impermeable bags, denitrification assays revealed that N2 production occurred at initial O2 concentrations of up to ~90 μm. Initial denitrification rates were not substantially affected by O2 in surficial (0–4 cm) sediments, whereas rates increased by twofold with O2 depletion in the at 4–6 cm depth interval. In a well mixed, flow-through stirred retention reactor (FTSRR), 29N2 and 30N2 were produced and O2 was consumed simultaneously, as measured online using membrane inlet mass spectrometry. We hypothesize that the observed high denitrification rates in the presence of O2 may result from the adaptation of denitrifying bacteria to recurrent tidally induced redox oscillations in permeable sediments at Janssand