Direct observation of a pair decay of neutral charmed particles produced in 400 GeVc proton interaction

The second evidence of a pair decay of charmed particles has been obtained in an emulsion chamber exposed to $\text{400}\text{GeV}\text{c}$ protons. The life time and production cross section of the charmed particles have been evaluated as several times 10^?13 s and several tens of microbarns.     

A Stereoselective synthesis of vinyl ethers from α-alkoxyaldehydes

A general, stereoselective approach to vinyl ethers from α-alkoxyaldehydes is described which features a stereocontrolled tri- n-butylstannyl addition/elimination sequence.     

Novel competing reaction of 1-methoxy-2-(trimethylsilyl)-3-hydroxy moiety in base-induced peterson olefination; mechanistic rationale of the reaction

In the base-induced Peterson olefination of diastereomerically pure 8-methoxy-7-(trimethylsilyl)-6-tridecanol, anti pathway to eliminate a methoxide ion was found to compete significantly with amply precedented syn-elimination of a trimethylsilanolate ion. On the basis of an extent of the competing reactions which depend markedly on the respective diastereomers (three from four diastereomers) the detailed mechanism of the syn-elimination emerged.     

Modular Redesign of a Cationic Lytic Peptide To Promote the Endosomal Escape of Biomacromolecules

Endocytosis is an important route for the intracellular delivery of biomacromolecules, wherein their inefficient endosomal escape into the cytosol remains a major barrier. Based on the understanding that endosomal membranes are negatively charged, we focused on the potential of cationic lytic peptides for developing endosomolysis agents to release such entrapped molecules. As such, a venom peptide, Mastoparan X, was employed and redesigned to serve as a delivery tool. Appending a tri‐glutamate unit to the N‐terminus attenuates the cytotoxicity of Mastoparan X by about 40 fold, while introduction of a Ni^II‐dipicolylamine complex enhances cellular uptake of the peptide by about 17 fold. Using the optimized peptide, various fluorescently labeled macromolecules were successfully delivered to the cytosol, enabling live‐cell imaging of acetylated histones.     

Carbon doping into GaAs using combined ion beam and molecular beam epitaxy method

Carbon (C) doping by combined ion beam and molecular beam epitaxy (CIBMBE) was investigated. In this technique, mass-analyzed C ions (¹²C⁺) are accelerated at low energies of 30 to 1000 eV and are irradiated onto growing GaAs substrate. Doping concentration control in CIBMBE can be very stably accomplished by simply adjusting the ion beam current density, which is independent of growth conditions of host materials. Experiments on systematic variation of C⁺ ion acceleration energy (E_C+) indicated that, in the energy range of E_C+<170 eV, net hole concentration (|N_A-N_D|) increases slightly as E_C+ increases. The highest |N_A-N_D| is obtained at E_C+ = 170 eV under the constant C⁺ ion beam current density. For E_C+>170 eV, |N_A-N_D| decreases dramatically with increasing E_C+, which can be explained in terms of enhanced sputtering effect. Although no evidence of damages induced by ion irradiation is shown for low E_C+ range of ≤170 eV, trace of damages is apparently observed for E_C+>170 eV.