These results provide the first direct demonstration of a double dissociation between LEC and MEC inputs to the hippocampus under conditions of exploration typically used to study hippocampal place cells.”
“In this study, we evaluated a new method for registering three-dimensional ultrasound (3DUS) data to external coordinate systems. First, 3DUS was registered to the stereo endoscope of a da Vinci Surgical System by placing a registration tool against an air-tissue boundary so that the 3DUS could image
ultrasound fiducials while the stereo endoscope could image camera markers on the same tool. The common points were buy LY333531 used to solve the registration between the 3DUS and camera coordinate systems. The target registration error (TRE) when imaging through a polyvinyl chloride ( PVC) tissue phantom ranged from 3.85 +/- 1.76 mm to 1.82 +/- 1.03 mm using one to four registration tool positions. TRE when imaging through an ex vivo liver tissue sample ranged from 2.36 +/- 1.01 mm to 1.51 +/- 0.70 mm using one to four registration tool positions. Second, using a similar method, 3DUS was registered to the kinematic coordinate system of a da Vinci Surgical System by using the da Vinci surgical manipulators to identify common points on an air-tissue boundary. TRE when imaging through a PVC tissue phantom ISRIB was 0.95 +/- 0.38 mm. This registration method is simpler and potentially
more accurate than methods using commercial motion tracking systems. This method may be useful in the future in augmented reality systems for laparoscopic
and robotic-assisted surgery.”
“Pressure applied during harvesting of the saphenous vein (SV) graft in coronary artery bypass surgery might change its mechanical properties and thereby decrease the patency. This study was performed to assess the mechanical properties of the SV graft distended manually with different levels of pressure and to determine the pressure level that induces changes in its structure and mechanics. Saphenous vein graft segments, collected from 36 patients undergoing coronary artery bypass surgery, were distended with pressures of either 50-60, 75-100, or 130-150 mmHg. Grafts were tested for the stress-strain relationship; the Young’s moduli at the low- and high-strain regions Tucidinostat nmr were calculated, and their structures were examined by light and electron microscopy. Pressures of 50-60 mmHg did not influence the mechanics of the vein graft, whereas pressures of 75-100 mmHg elevated the elastic modulus of the vein at the low-strain region while pressures above 130 mmHg increased the elastic moduli at both low- and high-strain regions. There was a prominent loss of microfibrils at all distending pressure levels. The mechanical results suggest that distending pressures above 75 mmHg might play a role in graft failure.