Hemodynamic microenvironment of coronary stent strut malapposition.

Objective: This study aims to investigate the micro-hemodynamic effects of strut malapposition in patient-specific stented coronary bifurcations.

Methods: Using the mapping-back technique, three-dimensional reconstructions of clinical post-stenting artery bifurcations with strut malapposition were accurately generated from optical coherence tomography scans of 9 patients. Computational fluid dynamics (CFD) simulations were then conducted with these models to examine the impact of strut malapposition on various fluid dynamic parameters, including flow patterns, vorticity, strain rates, viscosity, and wall shear stress (WSS).

Noise self-canceling picoscale twisted interferometer.

We show a noise self-canceling real-time picometer scale interferometer by exploiting the unique spiral phase structure of twisted light. We use a single cylindrical interference-lens to implement the twisted interferometer and perform simultaneous measurement on N phase-orthogonal single-pixel intensity pairs chosen on the petal of the daisy-flower-like interference pattern. A cancellation of various noises by three orders of magnitude was achieved in our setup compared with a conventional single-pixel detection, enabling a sub-100 picometer resolution in measuring a non-repetitive intracavity dynamic event in real-time.

Universal Stokes's nanomechanical viscometer.

Although, many conventional approaches have been used to measure viscosity of fluids, most methods do not allow non-contact, rapid measurements on small sample volume and have universal applicability to all fluids. Here, we demonstrate a simple yet universal viscometer, as proposed by Stokes more than a century ago, exploiting damping of capillary waves generated electrically and probed optically with sub-nanoscale precision. Using a low electric field local actuation of fluids we generate quasi-monochromatic propagating capillary waves and employ a pair of single-lens based compact interferometers to measure attenuation of capillary waves in real-time.

Identification and analysis of organic explosives from post-blast debris by nuclear magnetic resonance.

The growing threat of terrorism has triggered an urgent need to find effective ways to improve the analysis of explosives. This will aid forensic scientists in analysing the post-blast debris, which in turn helps the law enforcement agencies to frame suitable regulations. Analysis of post-blast debris is challenging as it hosts a massive amount of complexity.

Time-resolved nano-Newton force spectroscopy in air and vacuum using a load cell of ultra micro-balance.

We demonstrate a simple and versatile nanomechanical force measuring setup with 1 nN precision in air and vacuum using a load cell of an ultra-microbalance. We validate stability, precision, and linearity of the load cell with simple tests. The setup is customized to measure stress-strain response of biomaterials (silk, leaf, and flower) and capillary force in fluids.