The combination of ring closure and spatial constraints has a fundamental effect on the statistics of semiflexible polymers such as DNA. However, studies of the interplay between circularity and constraints are scarce and single-molecule experimental data concerning polymer conformations are missing. By means of atomic force microscopy we probe the conformation of circular DNA molecules in two ...

A plasma toroid is rotated toroidally to supersonic speeds by external means. The input power maintains the rotation and also heats the plasma. The thermoelectric effect from the resulting temperature gradient creates and maintains a poloidal magnetic field against resistive decay, confining the plasma in steady state. The shear in the rotation keeps the plasma stable to MHD kinks and interchan...

The rheology of granular materials near an interface is investigated through proton magnetic resonance imaging. A new cylinder shear apparatus has been inserted in the magnetic resonance imaging device, which allows the control of the radial confining pressure exerted by the outer wall on the grains and the measurement of the torque on the inner shearing cylinder. A multi-layer velocimetry sequ...

Attenuation and velocity dispersion are strongly dependent on pore fluids, particularly partial gas saturation, and thus could become valuable direct hydrocarbon indicators. Unfortunately, application of these properties is not frequent due to incomplete understanding of the phenomena and lack of appropriate tools to extract the information. Laboratory measurements at frequencies and amplitudes...

We conducted permeability measurements of basalt sampled from an exhumed ancient fault zone in the Cretaceous Shimanto accretionary complex in Japan, in order to investigate permeability structure and evolution following shear failure. Permeability showed a strong reduction with increase in the e#ective confining pressure and temperature. Rapid sealing at elevated temperatures was observed duri...