On 26 September 2014, Johan van Benthem, Professor of Pure and Applied Logic, delivered his valedictory lecture in the auditoriumof theUniversity of Amsterdam. Modern logic is the broad, exact science of information directed behaviour that plays an important role in connecting the humanities, exact sciences and social sciences at the university, and which forms the bedrock of our information so...

Background: One of the candidate landing sites for the Mars Science Laboratory is in the Mawrth region of Mars. The candidate landing ellipse is located on highly cratered terrain with extensive bedrock outcrop. Diverse hydrous minerals have been detected from orbit, providing strong motivation for sending a landed mission to this area. However, models for the accumulation of bedrock in the are...

[1] We evaluate the accuracy of 1 m, LiDAR-derived DEMs of an exposed bedrock channel, and use these highresolution terrain models to calculate erosional fluxes between four levels of strath terraces dated previously with Be. Recent investigations into the timing, rates, and processes by which rivers incise their bedrock channels have greatly enhanced our understanding of landscape evolution. H...

A 20-m-wide trench was excavated to bedrock on a hillslope at the Panola Mountain Research Watershed in the Piedmont region of Georgia to determine the effect of upslope drainage area from the soil and bedrock surfaces on the geochemical evolution of base cation concentrations in subsurface flow. Samples were collected from ten 2-m sections and five natural soil pipes during three winter rainst...

[1] Recent theoretical models suggest that topographic characteristics of bedrock channels are products of interactions among tectonics, substrate resistance, and the climatically modulated erosive ability of the river. The degree to which these factors influence the form of channel profiles is poorly quantified at present. Here we investigate bedrock channels developed across the southern flan...

Population statistics for As concentrations in rocks, sediments and ground water differ by geology and land use features in the New England region, USA. Significant sources of As in the surficial environment include both natural weathering of rocks and anthropogenic sources such as arsenical pesticides that were commonly applied to apple, blueberry and potato crops during the first half of the ...