Time-resolved Crystallographic Developments Utilising Detector Gating Techniques

New Laser Techniques for Time-Resolved Spectroscopy

A novel spectroscopic tool is presented for measuring the incoherent resonance decay (IRD) of selectively (6 MHz) prepared electronic states. The method utilizes electro-optic switching of a single laser mode that is on or off resonance with respect to the homogeneous molecular packets in the excited ensemble. The technique is applied to a variety of systems: gases at low and high pressures, mo...

Current Developments in Time-resolved X-ray Diffraction

Avalanche Detector with Ultraclean Response for Time-Resolved Photon Counting

Experimental tests have been carried out for characterizing the performance of a new single-photon avalanche diode. The detector is specifically designed for picosecond timecorrelated single photon counting, aiming to obtain a time response free from the tail effects and/or secondary bumps observed in all other available single-photon detectors. The experimental results confirm that an unpreced...

Allosteric action in real time: time-resolved crystallographic studies of a cooperative dimeric hemoglobin.

Protein allostery provides mechanisms for regulation of biological function at the molecular level. We present here an investigation of global, ligand-induced allosteric transition in a protein by time-resolved x-ray diffraction. The study provides a view of structural changes in single crystals of Scapharca dimeric hemoglobin as they proceed in real time, from 5 ns to 80 micros after ligand ph...

Utilising noise to improve an interictal spike detector.

Dithering is the process of intentionally adding artificially generated noise to an otherwise uncorrupted signal to actually improve the performance of an end overall system. This article demonstrates that a dithering procedure can be used to improve the performance of an EEG interictal spike detection algorithm. Using a previously reported algorithm, by adding varying amounts of artificially g...