Sensory coding mechanisms revealed by optical tagging of physiologically defined neuronal types.

Neural circuit analysis relies on having molecular markers for specific cell types. However, for a cell type identified only by its circuit function, the process of identifying markers remains laborious. We developed physiological optical tagging sequencing (PhOTseq), a technique for tagging and expression profiling of cells on the basis of their functional properties. PhOTseq was capable of selecting rare cell types and enriching them by nearly 100-fold. We applied PhOTseq to the challenge of mapping receptor-ligand pairings among pheromone-sensing neurons in mice. Together with in vivo ectopic expression of vomeronasal chemoreceptors, PhOTseq identified the complete combinatorial receptor code for a specific set of ligands.

Simple and accurate methods for quantifying deformation, disruption, and development in biological tissues.

When mechanical factors underlie growth, development, disease or healing, they often function through local regions of tissue where deformation is highly concentrated. Current optical techniques to estimate deformation can lack precision and accuracy in such regions due to challenges in distinguishing a region of concentrated deformation from an error in displacement tracking. Here, we present a simple and general technique for improving the accuracy and precision of strain estimation and an associated technique for distinguishing a concentrated deformation from a tracking error. The strain estimation technique improves accuracy relative to other state-of-the-art algorithms by directly estimating strain fields without first estimating displacements, resulting in a very simple method and low computational cost. The technique for identifying local elevation of strain enables for the first time the successful identification of the onset and consequences of local strain concentrating features such as cracks and tears in a highly strained tissue. We apply these new techniques to demonstrate a novel hypothesis in prenatal wound healing. More generally, the analytical methods we have developed provide a simple tool for quantifying the appearance and magnitude of localized deformation from a series of digital images across a broad range of disciplines.

A semi-automated system for the routine production of copper-64.

An automated system for the production of high specific activity (64)Cu via the irradiation of electroplated enriched (64)Ni targets has been developed. We have been operating this system continually on a biweekly or weekly basis for more than two years. Since the inception of this automated production system, (October 1, 2008), we have had 145 productions, produced 53562 mCi and shipped out 25629 mCi of this isotope to external users. We routinely produce over 400 mCi of this isotope per batch with a specific activity of 14,000 ± 7600 mCi/µmol for distribution to some 12-15 centers each production.