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PurposeThere have been several reports on the pullout strength of cortical bone trajectory (CBT) screws, but only one study has reviewed the stability of functional spine units using the CBT method. The purpose of this study was to compare vertebral stability after CBT fixation with that after pedicle screw (PS) fixation.MethodsIn this study, 20 lumbar spine (L5–6) specimens were assigned to two groups: the CBT model group that underwent CBT screw fixation (n = 10) and the PS model group that underwent pedicle screw fixation (n = 10). Using a six-axis material testing machine, bend and rotation tests were conducted on each model. The angular displacement from the time of no load to the time of maximum torque was defined as range of motion (ROM), and then, the mean ROM in the bend and rotation tests and the mean rate of relative change of ROM in both the bend and rotation tests were compared between the CBT and PS groups.ResultsThere were no significant differences between the CBT and PS groups with regard to the mean ROMs and the mean rate of relative change of ROMs in both the bend and rotation tests.ConclusionIntervertebral stability after CBT fixation was similar to that after PS fixation.

1Mbit D‐RAM. the most advanced VLSI device, is realized by a high performance stepper with the conventional optical techniques. However, as the optical lithography has an inherent limit of resolution, new technologies are being developed rapidly for the development of new generation VLSI devices (4M‐16Mbit D‐RAM) using shorter wavelength photons of i‐line. Electron beam (EB) lithography is already in practical mask making products, but the resolution limit is about 0.5 μm because of proximity effects. In order to make higher resolution and higher precision masks, high voltage EB technique is being developed to minimize the proximity effect, and fabricated 0.25 μm line and space by a single scan at 50kV. X‐ray technology 1; becoming practical after a long laboratory‐level study, using high performance X‐ray resists (CPMS: chlorinated polymetylstylene). Focused Ion Beam (FIB) technology has been anticipated for its capability of submicron lithography due to a reduced proximity effect. High speed submicron Si MOSFET and GaAs MESFET with 0.25 μm gate have been fabricated using FIB technology. Activities of submicron lithography technology in Japan (optical stepper, EB, X‐ray, and FIB) are described.

Background: Studies have shown that walking in forests can have a relaxation effect, but the participants only walked for about 15 minutes.

Articles you may be interested inCollision of hyperthermal atoms with a solid surface. I. Energy dissipation in the solid J. Chem. Phys. 94, 4055 (1991); 10.1063/1.460655 Monte Carlo simulation of kilovolt electron transport in solidsA new technique to determine the depth distribution of energy loss, the so-called depth-dose function, is described for electrons whose energies ranged from 15 to 30 keY at normal and 45 0 incident angles. This method is based on a series of measurements of currents induced by the penetration of energetic electrons through a metal-oxide-semiconductor-structure (AI-SiOrSi) specimen whose metal electrode is formed by an aluminum layer deposited in a stepwise manner. The experimental depth-dose function and range-energy relation are compared with other experimental and theoretical results. A particular interest was taken in the comparison of the experimental results with those predicted by our Monte Carlo calculations to confirm the good agreement between them. Furthermore, the ratio of the product of mobility and lifetime to the mean electron excitation energy in Si0 2 was also determined to be p.TIE A = 0.10 XIO-11 cm/V2, which may be ranked between the values reported by Everhart and HolT and by Goodman. The elTects of space charge in Si0 2 are also discussed. Is·Let us denote the direction of the current flowing