Raman and x-ray diffraction studies of Ba doped germanium clathrate Ba8Ge43 at high pressure

High-pressure Raman and x-ray diffraxtion (XRD) measurements of a defect clathrate Ba8Ge43□3 have been carried out at room temperature up to 40 GPa. Three vibrational modes associated with guest Ba atoms were observed in the low-frequency region, and the structureless spectrum due to Ge vacancies was found in the framework vibrational region. The Raman spectra shows a pressure-induced phase transition at 8 GPa, which is due to the structural distortion through the three-bonded Ge atoms and to the change in the guest-host electronic interaction. Both Raman spectra and XRD patterns present the evidence for the amorphization of Ba8Ge43 around 30–40 GPa. The isostructural phase transition often present in intercalated silicon clathrates and associated with a large volume reduction was not observed for Ba8Ge43 up to 40 GPa. The pressure dependence of the lattice constant (a) normalized by a0 at 1 bar (a/a0) shows the continuous decrease with pressure until amorphization. From the good coincidence of this curve between Ba8Ge43 and Ba8Si46 at pressures above 15 GPa, we propose that the isostructural phase transition found for Ba8Si46 at 15 GPa may be originated from a defect-induced transformation to Ba8Si43□3 with the help of their theoretical equation of state by the first-principles calculations

The effect of rapamycin on biodiesel-producing protist <i>Euglena gracilis</i>

<p>Rapamycin induces autophagy with lipid remodeling in yeast and mammalian cells. To investigate the lipid biosynthesis of <i>Euglena gracilis</i>, rapamycin was supplemented in comparison with two model algae, <i>Chlamydomonas reinhardtii</i> and <i>Cyanidioschyzon merolae</i>. In <i>Euglena</i>, rapamycin induced the reduction of chlorophylls and the accumulation of neutral lipids without deterring its cell proliferation. Its lipidomic profile revealed that the fatty acid composition did not alter by supplementing rapamycin. In <i>Chlamydomonas</i>, however, rapamycin induced serious growth inhibition as reported elsewhere. With a lower concentration of rapamycin, the alga accumulated neutral lipids without reducing chlorophylls. In <i>Cyanidioschyzon</i>, rapamycin did not increase neutral lipids but reduced its chlorophyll content. We also tested fatty acid elongase inhibitors such as pyroxasulfone or flufenacet in <i>Euglena</i> with no significant change in its neutral lipid contents. In summary, controlled supplementation of rapamycin can increase the yield of neutral lipids while the scheme is not always applicable for other algal species.</p> <p>Lipid profile of <i>Euglena gracilis</i> under supplementation of rapamycin. With <10 µM rapamycin, the neutral lipid contents increase without deterring cell growth.</p

Well-differentiated fetal adenocarcinoma of the lung in a 20-year-old woman

A 20-year-old woman was found to have a tumor shadow on chest X-ray examination during mass screening and was admitted to our hospital. The chest radiograph revealed a round tumor in the right upper lung field. Chest computed tomography (CT) showed a well-defined, 3-cm-diameter mass in the right upper lobe. The patient underwent a right upper lobectomy under video-assisted thoracoscopic surgery. The postoperative pathological diagnosis was well-differentiated fetal adenocarcinoma (WDFA), stage IA (pT1bN0M0). The patient was well and free of disease four years after surgery. WDFA is a rare pulmonary neoplasm resembling fetal lung and classified as a variant of adenocarcinoma. WDFA occurs in younger people more often than the other histological types of primary lung cancer. An additional young case of WDFA is reported, along with a review of the relevant literature