By developing a wide-field scheme for spectral measurement and implementing photoswitching, we synchronously obtained the fluorescence spectra and positions of ∼10(6) single molecules in labeled cells in minutes, which consequently enabled spectrally resolved, 'true-color' super-resolution microscopy. The method, called spectrally resolved stochastic optical reconstruction microscopy (SR-STORM), achieved cross-talk-free three-dimensional (3D) imaging for four dyes 10 nm apart in emission spectrum. Excellent resolution was obtained for every channel, and 3D localizations of all molecules were automatically aligned within one imaging path.

The application of electron microscopy to hydrated biological samples has been limited by high-vacuum operating conditions. Traditional methods utilize harsh and laborious sample dehydration procedures, often leading to structural artefacts and creating difficulties for correlating results with high-resolution fluorescence microscopy. Here, we utilize graphene, a single-atom-thick carbon meshwork, as the thinnest possible impermeable and conductive membrane to protect animal cells from vacuum, thus enabling high-resolution electron microscopy of wet and untreated whole cells with exceptional ease. Our approach further allows for facile correlative super-resolution and electron microscopy of wet cells directly on the culturing substrate. In particular, individual cytoskeletal actin filaments are resolved in hydrated samples through electron microscopy and well correlated with super-resolution results.

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In the wake of a major corruption conspiracy, the U.S. Navy reformed husbanding service procedures to increase competition, auditability, and accountability with the goal of reducing expenditures. The first policy change, Off-Ship Bill Pay (OSBP), formalized a process for procuring, rendering, and paying for husbanding services to increase oversight. The second policy change increased the use of multiple award contracts (MACs), in which multiple vendors are awarded a contract over a region, increasing competition for individual port visits. The purpose of this article is to analyze the effects of these policy changes on the cost of husbanding services. Multiple regression was used to account for port visit characteristics that affect cost such as ship type and the number of days in port. MACs demonstrated a reduction effect on the cost of port visits. Further, OSBP appears to have a negligible effect on port visit cost after the initial learning curve for both Navy personnel and vendors.