Bess G. Koffman

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Waters from an extensive sulfide-rich aquifer emerge in the Frasassi cave system, where they mix with oxygen-rich percolating water and cave air over a large surface area. The actively forming cave complex hosts a microbial community, including conspicuous white biofilms coating surfaces in cave streams, that is isolated from surface sources of C and N. Two(More)
We describe a microcontroller-based ice core melting and data logging system allowing simultaneous depth coregistration of a continuous flow analysis (CFA) system (for microparticle and conductivity measurement) and a discrete sample analysis system (for geochemistry and microparticles), both supplied from the same melted ice core section. This hybrid(More)
To assess the role of methodological differences on measured trace-element concentrations in ice cores, we developed an experiment to test the effects of acidification strength and time on dust dissolution using snow samples collected in West Antarctica and Alaska. We leached Antarctic samples for 3 months at room temperature using nitric acid at(More)
We present the first high-resolution (sub-annual) dust particle data set from West Antarctica, developed from the West Antarctic Ice Sheet (WAIS) Divide deep ice core (79.468 S, 112.086 W), and use it to reconstruct changes in atmospheric circulation over the past 2400 years. We find a background dust flux of ∼ 4 mg m−2 year−1 and a mode particle size of(More)
Sir, in reply to the letter in a recent edition of the BDJ, Different priorities (BDJ 2011; 211: 447-448), I should like to add my comments. I am the Dental Coordinator for Christian Relief Uganda (www. christianreliefuganda.org). I was present at the conference in Manchester where Dr Holmgren spoke. For six years we have run pain relief dental clinics in(More)
[1] We present a new method for inferring the relative location (lowversus high-southern latitude), and therefore the potential climatic impact, of past eruptions based on the particle size distribution (PSD) of micrometer-sized ash measured continuously in the West Antarctic Ice Sheet (WAIS) Divide ice core. We find that particles from a high-southern(More)
We present three new and 14 retrospective cases of polyradiculopathy in sarcoidosis. Of these, 71% had weakness and 59% areflexia of the lower extremities, and 35% had sphincter dysfunction. Cases often were associated with central nervous system sarcoidosis. All cases involved thoracolumbar or lumbosacral roots, except a single case of cervical(More)
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