Input and output budgets of radiocesium concerning the forest floor in the mountain forest of Fukushima released from the TEPCO's Fukushima Dai-ichi nuclear power plant accident

AbstractEstimations of radiocesium input and output concerning the forest floor within a mountain forest region have been conducted in the north and central part of the Abukuma Mountains of Fukushima, northeast Japan, after a 2–3 year period following the TEPCO Fukushima Dai-ichi nuclear power plant accident. The radiocesium input and output associated with surface washoff, throughfall, stemflow, and litterfall processes at experimental plots installed on the forest floor of evergreen Japanese cedars and deciduous Konara oaks have been monitored. Despite the high output potential in the mountainous forest of Fukushima, the results at both monitoring locations show the radiocesium input to be 4–50 times higher than the output during the summer monsoon in Fukushima. These results indicate that the radiocesium tends to be preserved in the forest ecosystem due to extremely low output ratios (0.05%–0.19%). Thus, the associated fluxes throughout the circulation process are key issues for the projecting the environmental fate of the radiocesium levels, along with the subsequent reconstruction of life emphasized within the setting

Anomalies of the bile ducts: a case report of direct drain of the cystic duct into the papilla of Vater.

Direct drain of the cystic duct and drain of the biliary tract through an internal fistula into the duodenum in a 81-year-old man were endoscopically diagnosed without an operation.</p

A Simple Synthetic Route for the Preparation of Tetramethylglycolide from Lactic Acid

Poly(tetramethylglycolide), a chemical recyclable polymer, is currently attracting a lot of interest as a substitute for poly(L-lactic acid). We report here a simple and convenient route for the synthesis of tetramethylglycolide (TMG) from lactic acid. This method involves three steps: (1) one-step protection of lactic acid by cyclic acetalization employing acetone; (2) α-methylation of the obtained 2,2,5-trimethyl-1,3-dioxolan-4-one; and (3) one-pot synthesis of TMG including the hydrolysis of 2,2,5,5-tetramethyl-1,3-dioxolan-4-one. We found significant advantages of the incorporation of existing reactions in the synthesis of TMG

Racemization-free Monomer: α-Hydroxyisobutyric Acid from Bio-based Lactic Acid

In order to solve the important problem of the racemization of poly(L-lactic acid), a high yield of racemization-free monomer: a-hydroxyisobutyric acid (HIBA) was synthesized from bio-based lactic acid by methylation using specific bases with bulky side groups. Obtained HIBA can be converted into poly(tetramethylglycolide), which is racemization-free and has higher melting and glass transition points than poly(L-lactic acid)

Isotopic evidence of plutonium release into the environment from the Fukushima DNPP accident

The Fukushima Daiichi nuclear power plant (DNPP) accident caused massive releases of radioactivity into the environment. The released highly volatile fission products, such as 129mTe, 131I, 134Cs, 136Cs and 137Cs were found to be widely distributed in Fukushima and its adjacent prefectures in eastern Japan. However, the release of non-volatile actinides, in particular, Pu isotopes remains uncertain almost one year after the accident. Here we report the isotopic evidence for the release of Pu into the atmosphere and deposition on the ground in northwest and south of the Fukushima DNPP in the 20–30 km zones. The high activity ratio of 241Pu/239+240Pu (> 100) from the Fukushima DNPP accident highlights the need for long-term 241Pu dose assessment, and the ingrowth of 241Am. The results are important for the estimation of reactor damage and have significant implication in the strategy of decontamination

Poly(tetramethyl glycolide) from Renewable Carbon, a Racemization-Free and Controlled Depolymerizable Polyester

Racemization-free and depolymerization-controllable poly(tetramethyl glycolide) (PTMG) was synthesized from renewable resources: D/L-lactic acids and pyruvic acid. PTMG overcomes the undesirable properties of poly(lactic acid) such as low heat-resistance and racemization causing the decrease in crystallinity. PTMG was shown to have a higher melting point than 200 °C and to be a superior recyclable material capable of being depolymerized controllably into cyclic dimer tetramethyl glycolide (TMG) or methacrylic acid (MA) by using specific catalysts. PTMG can be reversibly synthesized from the depolymerized TMG. Moreover, biomass-based poly(methyl methacrylate) (PMMA) was prepared from the recovered MA