Atomic-Number (Z)-Correlated Atomic Sizes for Deciphering Electron Microscopic Molecular Images

With the advent of atomic-resolution transmission electron microscopy (AR-TEM) achieving sub-{\AA}ngstrom image resolution and submillisecond time resolution, an era of visual molecular science where chemists can visually study the time evolution of molecular motions and reactions at atomistic precision has arrived. However, the appearance of experimental TEM images often differs greatly from that of conventional molecular models, and the images are difficult to decipher unless we know in advance the structure of the specimen molecules. The difference arises from the fundamental design of the molecular models that represent atomic connectivity and/or the electronic properties of molecules rather than the nuclear charge of atoms and electrostatic potentials that are felt by the e-beam in TEM imaging. We found a good correlation between the atomic number (Z) and the atomic size seen in TEM images when we consider shot noise in digital images. We propose here Z-correlated (ZC) atomic radii for modeling AR-TEM images of single molecules and ultrathin crystals, with which we can develop a good estimate of the molecular structure from the TEM image much more easily than with conventional molecular models. Two parameter sets were developed for TEM images recorded under high-noise (ZCHN) and low-noise (ZCLN) conditions. The new molecular models will stimulate the imaginations of chemists planning to use AR-TEM for their research.Comment: 27 pages, 6 figure

Isolated Renal Metastasis from Non-Small-Cell Lung Cancer: Report of 2 Cases

Renal metastasis from non-small-cell lung cancer is rather uncommon; isolated metastasis especially is rare. Herein we report 2 cases who developed a solitary renal metastasis after undergoing a curative resection for non-small-cell lung cancer. They received nephrectomy

Bleb formation in small unruptured intracranial aneurysm as a predictor of early rupture

Small unruptured aneurysms are thought to have a low risk of rupture, but the management of such lesions is still controversial. A 73-year-old man with a small anterior communication artery aneurysm, 4 mm in diameter, while on follow-up, developed an aneurysmal subarachnoid hemorrhage 2 weeks after the detection of a newly emerged bleb on the surface of the aneurysm. In conclusion, the formation of a bleb should be considered as a warning sign of an impending rupture, and treatment should be provided even for patients with small aneurysms

ヒガシ オングルトウ サン ザクロイシ ニ ツイテ

The sample was collected by Prof. Torii of Chiba University. Its colour is reddish brown and translucent and it forms a somewhat elongated crystal. It shows a few cracks and is brittle. Observed under the microscope, the greater part of the thin sections is quite homogeneous, but the bottom part of the crystal contains very small amount of hornblende, limonite and albite. We select its homogeneous part for our study. The following result were obtained: S.G. 3.954±0.005 a_0 11.530 Å (lattice constant) nNa 1.778±0.002 Si0_2 40.02% Al_20_3 21.90 Fe_20_3 1.53 FeO 21.34 CaO 5.20 MgO 8.94 K_20 0.01 Na_20 0.06 H_20^- 0.18 H_20^+ - Ti0_2 0.06 P_20_5 0.00 MnO 0.93 SrO 0.00 Total 100.17% F 0.002% Less 0 for F: 0.001% Rb and Li were detected by spectrochemical analysis, but Cr was not detected and, therefore, uvarovite-component is absent. Other rarer elements were not found. From the result of chemical analysis the authors studied its garnet-components and obtained the following results: Almandite 47.64% Andradite 4.59% Pyrope 35.49% Grossularite 10.10% Spessartite 2.18% By Boeke\u27s classification this constitution belongs to pyralspite

Homocoupling-free iron-catalysed twofold C–H activation/cross-couplings of aromatics via transient connection of reactants

UTokyo FOCUS Press releases "Simplified synthesis Researchers dramatically simplify and streamline organic chemical synthesis " https://www.u-tokyo.ac.jp/focus/en/press/z0508_00037.htm

Atomically precise incorporation of BN doped rubicene into graphene nanoribbons

Substituting heteroatoms and non-benzenoid carbons into nanographene structure offers an unique opportunity for atomic engineering of electronic properties. Here we show the bottom-up synthesis of graphene nanoribbons (GNRs) with embedded fused BN-doped rubicene components on a Au(111) surface using on-surface chemistry. Structural and electronic properties of the BN-GNRs are characterized by scanning tunneling microscopy (STM) and atomic force microscopy (AFM) with CO-terminated tips supported by numerical calculations. The periodic incorporation of BN heteroatoms in the GNR leads to an increase of the electronic band gap as compared to its undoped counterpart. This opens avenues for the rational design of semiconducting GNRs with optoelectronic properties.Comment: 18 pages, 4 figure

Possible activation by the green tea amino acid theanine of mammalian target of rapamycin signaling in undifferentiated neural progenitor cells in vitro

AbstractWe have shown marked promotion of both proliferation and neuronal differentiation in pluripotent P19 cells exposed to the green tea amino acid theanine, which is a good substrate for SLC38A1 responsible for glutamine transport. In this study, we evaluated the activity of the mammalian target of rapamycin (mTOR) kinase pathway, which participates in protein translation, cell growth and autophagy in a manner relevant to intracellular glutamine levels, in murine neural progenitor cells exposed to theanine. Exposure to theanine promoted the phosphorylation of mTOR and downstream proteins in neurospheres from embryonic mouse neocortex. Although stable overexpression of SLC38A1 similarly facilitated phosphorylation of mTOR-relevant proteins in undifferentiated P19 cells, theanine failed to additionally accelerate the increased phosphorylation in these stable transfectants. Theanine accelerated the formation of neurospheres from murine embryonic neocortex and adult hippocampus, along with facilitation of both 5-bromo-2’-deoxyuridine incorporation and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide reduction in embryonic neurospheres. In embryonic neurospheres previously exposed to theanine, a significant increase was seen in the number of cells immunoreactive for a neuronal marker protein after spontaneous differentiation. These results suggest that theanine activates the mTOR signaling pathway for proliferation together with accelerated neurogenesis in murine undifferentiated neural progenitor cells