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A simple method of synthesizing an enantiomeric N-fluoro-3-cyclohexyl-3-methyl-2,3-dihydrobenzo[1,2-d]isothiazole 1,1-dioxide (CMIT-F) has been devised. The compound is capable of effecting the electrophilic asymmetric fluorination of ketone metal enolates to produce optically active alpha-fluoroketones with enantioselectivity of up to 88% ee. The CMIT-F structure is capable of producing stable but reactive N-F bonds and are designed to produce steric factors that induce asymmetric induction.

The velocity Verlet is the most superior algorithm in molecular dynamics simulations of flow problems. This is due to the large time interval it allows and the minimal computer memory it requires. The leapfrog is the next best algorithm, followed by the Beeman. Meanwhile, the complexity and poor performance of the 4-value Gear algorithm in terms of stability and the energy fluctuation make it inferior to the other molecular dynamics algorithms. The A and B algorithms perform even more poorly than the 4-value Gear, making them inappropriate for the simulations of flow problems.

A channel doping profile for pmetal oxide semiconductor field-effect transistors using Sb multiple ion implantation is proposed. The profile is uniform in the region deeper than the calculated range of the ion implanted profile of minimum ion implantation energy. A silicon-On-Insulator substrate is assumed in a numerical and experimental study. The transistor is found to be operable with a gate length of as low as 0.1 micrometer.

The purpose of the present study is to clarify the Rankine-Hugoniot relations for Lennard-Jones liquids. First, Monte Carlo simulations are conducted to evaluate the state quantities such as the pressures, the internal energies, and the sound velocities. These computed values are used to obtain the approximate expressions for the state quantities by the method of least squares. The Rankine-Hugoniot relations are then clarified numerically as a function of the shock Mach number by solving the basic equations together with those approximate expressions. For liquid shock waves, not only the pressure but also the temperature increases much larger than those for an ideal gas. The results obtained here enable us to conduct more efficient molecular dynamics simulations such as simulating shock fronts alone for the investigation of the internal structures of liquid shock waves.

Background: Axolotls have remarkable organ‐level regeneration capability. They can regenerate their limbs, tail, brain, gills, and heart. The liver had been considered to be a regenerative organ in these highly regeneration‐competent animals. Therefore, no research had been performed on liver regeneration in urodele amphibians. In the present study, we focused on axolotl liver regeneration and found a unique regeneration mechanism compared with other vertebrates. Results: Partial hepatectomy (PH) was performed to assess axolotl liver regeneration. Regeneration was assessed using block‐face imaging (CoMBi), histology, cell proliferation, weight gain, and Albumin (Alb) + area. Axolotl liver histology was compared with other vertebrates. Axolotl liver consists of Glisson's capsule, sinusoids, and hepatic cord with no apparent lobule structures. Hepatocytes were mononucleated or multinucleated. PH increased the multinucleated hepatocytes and the Alb + area, but there was no apparent liver shape recovery even 40 days after PH. Gene expression pattern suggests that no epimorphic regeneration takes place. We also found that the increase in the number of proliferating hepatocytes was regulated by ERK‐signaling. Conclusion: Our findings suggest that axolotls, which have epimorphic regeneration ability, regenerate their liver via unique mechanisms, compensatory congestion. Key Findings: Liver regeneration was not previously described in the regeneration‐competent animal, Ambystoma mexicanum.Axolotl liver has structures that are similar to those of other vertebrates.Axolotls cannot restore the liver shape after partial hepatectomy.Partial hepatectomy increased the number and multinucleation of hepatocytes, resulting in an increase in the albumin (Alb)+ area.ERK signaling regulates axolotl liver regeneration.Axolotl liver regeneration is achieved via compensatory congestion. [ABSTRACT FROM AUTHOR]