Mercury Free Microscopy: An Opportunity for Core Facility Directors

Mercury Free Microscopy (MFM) is a new movement that encourages microscope owners to choose modern mercury free light sources to replace more traditional mercury based arc lamps. Microscope performance is enhanced with new solid state technologies because they offer a more stable light intensity output and have a more uniform light output across the visible spectrum. Solid state sources not only eliminate mercury but also eliminate the cost of consumable bulbs (lifetime ∼200 hours), use less energy, reduce the instrument down time when bulbs fail and reduce the staff time required to replace and align bulbs. With lifetimes on the order of tens of thousands of hours, solid state replacements can pay for themselves over their lifetime with the omission of consumable, staff (no need to replace and align bulbs) and energy costs. Solid state sources are also sustainable and comply with institutional and government body mandates to reduce energy consumption, carbon footprints and hazardous waste. MFM can be used as a mechanism to access institutional financial resources for sustainable technology through a variety of stakeholders to defray the cost to microscope owners for the initial purchase of solid state sources or the replacement cost of mercury based sources. Core facility managers can take a lead in this area as “green” ambassadors for their institution by championing a local MFM program that will save their institution money and energy and eliminate mercury from the waste stream. Managers can leverage MFM to increase the visibility of their facility, their impact within the institution, and as a vital educational resource for scientific and administrative consultation.     

Characterization ofClostridium bifermentans and its biotransformation of 2,4,6-trinitrotoluene (TNT) and 1,3,5-triaza-1,3,5-trinitrocyclohexane (RDX)

Summary We have determined that an organism able to degrade both RDX and TNT in a pure culture is a strain ofClostridium bifermentans. The consortium from which this organism is derived also degrades these compounds, and we suspect thatC. bifermentans is also the responsible organism within that consortium. The bioconversion of RDX and TNT occurs under anaerobic conditions both in the consortium and in pure culture without the need of an added reductant. The presence of co-metabolites speeded these biotransformations.     

Nonlinear terms produced by passing amplitude-modulated sinusoids through a hair cell transducer function

We derive mathematically the output of Corey and Hudspeth's hair cell transducer function for the following cases: (1) the input is a single carrier whose output is modulated by the sum of two sinusoids; (2) the input is the sum of two carriers, each of which is amplitude-modulated by a single sinusoid. The theoretical results are similar to the results of an experiment in which field potentials were recorded from the human scalp while one ear was stimulated with auditory waveform (1) and with auditory waveform (2) of the cases above.