The Grounds and Extent of Legal Responsibility

To question that is the title of this symposium, What Do Compensatory Damages Compensate?, requires consideration of the basic grounds and purposes of legal responsibility. The question is usefully brought into sharper focus by the specific questions and puzzles posed to the contributors to stimulate thought and discussion

Detection of a common odd aberration in confocal reflection microscopy by means of an edge scan

In reflection laser scanning microscopes, detection of odd aberrations is challenging because aberration cancellation can occur after the second passage of the light beam through the system. A method is proposed that uses a sample containing high spatial frequencies, such as an edge scan, to detect and measure the presence of odd aberrations. The new approach is demonstrated by scanning the focal spot over an edge in a confocal reflection microscope when coma is present in the imaging system (a common odd aberration). It is shown that the edge response displays characteristic distortions which are typical of coma. Detection of amplitude, sign and orientation of the coma aberration is made possible by comparison of the measured edge responses with theoretical curves

Bacterial Bio-indicators of Marcellus Shale Activities in Pennsylvania: A Molecular Ecology Survey

The practice of hydraulic fracking has increased over the years especially in Pennsylvania where most of the subterraneous gas-rich Marcellus Shale formations are located. Our previous work showed that headwater streams in proximity to hydraulic fracking operations have significantly different bacterial assemblages as compared to un-impacted streams in central PA. Aquatic bacterial communities are of great importance because they are often the ‘first-responders’ to environmental perturbations. We are interested in which bacteria become enriched, as this might serve as robust biomarkers of fracking, and can potentially biodegrade constituents of fracking fluids. In this study, we plan to expand upon our previous work to identify additional sentinel bacterial taxa in other areas in PA (Northeast and Southwest) heavily impacted by fracking. Water and sediment samples have been collected from Northern Pennsylvania (n=31) and Southwestern (n=11) regions upstream and downstream of fracking activities. Bacterial community profiles of these samples were generated via high-throughput sequencing of the 16S rRNA, a robust phylogenetic marker for bacterial identification. The data generated provide a snapshot of all bacteria taxa present and their relative abundance. Thus, differences in bacterial community structure between impacted and un-impacted environments can help glean which bacterial taxa are responding to environmental perturbations associated with fracking. This research can help us generate a list of potential bioindicators of nascent fracking activities and can be used to help track impacts and bioremediation potential within environmental scenarios

Non-iterative aberration retrieval based on the spot shape around focus

A non-iterative, robust, aberration retrieval method to determine primary aberrations by utilizing the intensity distribution at and around focus is presented. The primary Zernike aberrations (coma, spherical aberration and astigmatism) are retrieved by fitting a set of orthogonal circle functions within the central region of the intensity distribution recorded at 3 different axial planes, typically taken at best focus and either side of focus. Aberration indicators are derived from these fits for each primary aberration and it is shown that these indicators can be used for aberration retrieval. The selected indicators vary almost linearly with the magnitude of aberration up to 0.13λ rms, corresponding to a Strehl ratio of 0.44. In the presence of multiple primary aberrations, the method is found to be reliable for a total rms wavefront deviation below 0.10λ (Strehl ratio of 0.68). This approach is linear and non-iterative and will therefore be beneficial for applications where speed and limiting photon exposure is important such as wavefront correction in biomedical imaging

Ab initio structure search and in situ 7Li NMR studies of discharge products in the Li-S battery system.

The high theoretical gravimetric capacity of the Li-S battery system makes it an attractive candidate for numerous energy storage applications. In practice, cell performance is plagued by low practical capacity and poor cycling. In an effort to explore the mechanism of the discharge with the goal of better understanding performance, we examine the Li-S phase diagram using computational techniques and complement this with an in situ (7)Li NMR study of the cell during discharge. Both the computational and experimental studies are consistent with the suggestion that the only solid product formed in the cell is Li2S, formed soon after cell discharge is initiated. In situ NMR spectroscopy also allows the direct observation of soluble Li(+)-species during cell discharge; species that are known to be highly detrimental to capacity retention. We suggest that during the first discharge plateau, S is reduced to soluble polysulfide species concurrently with the formation of a solid component (Li2S) which forms near the beginning of the first plateau, in the cell configuration studied here. The NMR data suggest that the second plateau is defined by the reduction of the residual soluble species to solid product (Li2S). A ternary diagram is presented to rationalize the phases observed with NMR during the discharge pathway and provide thermodynamic underpinnings for the shape of the discharge profile as a function of cell composition.Fellowship support to KAS from the ConvEne IGERT Program of the National Science Foundation (DGE 0801627) is gratefully acknowledged. AJM acknowledges the support from the Winton Programme for the Physics of Sus-tainability. PDM and DSW thank the UK-EPSRC for financial support. This research made use of the shared experimental facilities of the Materials Research Laboratory (MRL), sup-ported by the MRSEC Program of the NSF under Award No. DMR 1121053. The MRL is a member of the NSF-funded Mate-rials Research Facilities Network (www.mrfn.org). CPG and ML thank the U.S. DOE Office of Vehicle Technologies (Con-tract No. DE-AC02-05CH11231) and the EU ERC (via an Ad-vanced Fellowship to CPG) for funding.This is the final published version. It first appeared at http://pubs.acs.org/doi/abs/10.1021/ja508982p