It is pointed out that, for microscale Reynolds numbers less than about 1000, the passive scalar spectrum in turbulent shear flows is less steep than anticipated and that the Obukhov–Corrsin constant can be defined only if the microscale Reynolds number exceeds this value. In flows where the large-scale velocity field is essentially isotropic ~as in grid turbulence!, the expected 5/3 scaling is...

We have used multiphoton absorption polymerization to fabricate a series of microscale polymer cantilevers. Atomic force microscopy has been used to characterize the mechanical properties of microcantilevers with spring constants that were found to span more than four decades. From these data, we extracted a Young’s modulus of E=0.44 GPa for these microscale cantilevers. The wide stiffness rang...

Microscale heterogeneity in the extracellular matrix (ECM) provides spatial information that allows tissues to develop and function properly in vivo. This heterogeneity in composition (chemistry) and structure (geometry) creates distinct microenvironments for the cells that comprise a tissue. In response, populations of cells can coordinate their behaviors across micrometer-to-millimeter length...

The concept of double stranded DNA forming triple helical complexes with a third strand of nucleic acids via so called Hoogsteenhydrogen bonds has been well established for the last 50 years. However, the topic reentered the big stage with recent publications pointing to an existence of these structures in vivo, highlighting their putative role in chromatin organization and transcriptional regu...

Abstract We propose a design, micro fabrication process, and nuclear magnetic resonance (NMR) based evaluation, of field gradient chip. The uni-axial linear z -gradient coil design was computed by stream-function method, with the optimisation goal to exhibit minimum power dissipation. coils were implemented on two bi-planes, which built-up Cu electroplating in combination photo definable dry-fi...

Trapping and manipulation of microscale and nanoscale particles is demonstrated using the sole action of hydrodynamic forces. We developed an automated particle trap based on a stagnation point flow generated in a microfluidic device. The hydrodynamic trap enables confinement and manipulation of single particles in low viscosity (1-10 cP) aqueous solution. Using this method, we trapped microsca...