Microstructures and mechanical properties of titanium/biodegradable-polymer FGM for bone tissue fabricated by spark plasma sintering method

Ti and Ti alloys are widely used as metallic implants, because of their good mechanical properties and nontoxic behavior. However, they have problems as the implant-materials, namely, high Young's modulus comparing that of bone and low bonding ability with bone. There is a need to develop the Ti and Ti alloys with lower Young's modulus and good bonding ability. In previous study, Ti composite containing biodegradable poly-l-lactic-acid (PLLA) fiber has been fabricated to improve these problems. However, this composite has low strength because of the imperfect sintering of Ti matrix. To improve its strength, sintering of Ti matrix should be completed. In this study, Ti–NaCl composite material was fabricated by spark plasma sintering (SPS) method using powder mixture of Ti and NaCl to complete the sintering of Ti matrix. To obtain porous Ti samples, Ti–NaCl composite were put into hot water of 317 K. The porous Ti was dipped into PLLA melt in order to introduce PLLA into the pores of porous Ti. Finally, Ti/PLLA composite was obtained, and PLLA plays a role as reinforcement of Ti matrix. It was found that the Ti/PLLA composite has gradient structure and mechanical properties.     

Introduction of the archaebacterial geranylgeranyl pyrophosphate synthase gene into Chlamydomonas reinhardtii chloroplast

Geranylgeranyl pyrophosphate (GGPP) synthase gene (gds) derived from a thermophilic Archae Sulfolobus acidocaldarius, was introduced into a unicellular green alga Chlamydomonas reinhardtii chloroplast. Heat treatment abolished the prenyltransferase activity of the wild strain, but the activity of the transforment remained. The transformant accumulated gds gene mRNA and translation product.     

Synthesis of chiral hybrid nanotubes of magnetite nanoparticles and conducting polymers

New chiral magnetite nanoparticles with a polymerizable group produced polymer composite films on an electrode surface and the hybrid nanotubes of magnetite nanoparticles and polythiophene from their template-based electropolymerization.     

Enhanced production of extracellular inulinase by the yeast Kluyveromyces marxianus in xylose catabolic state

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Inter-laboratory evaluation studies for establishment of notified ELISA methods for allergic substances (peanuts)

Inter-laboratory evaluation studies were conducted for ELISA methods for allergic substances (peanuts). Extracts of biscuit, sauce, chocolate and butter spiked with peanut standard protein at a level of 5-20 ng/mL as sample solutions were analyzed in replicate in 10 laboratories. Coefficients of variation (CVs) of the ELISA methods using a Peanut Protein ELISA Kit (Peanut kit) and a FASTKIT Peanut ELISA kit (Peanut ELISA kit) were mostly below 10%. Mean recoveries of the peanut standard protein from the food extracts were over 40% in the two ELISA methods. Repeatability relative standard deviations of peanut standard protein in four food extracts were in the ranges of 15.2-49.7% and 3.0-28.3% for the Peanut kit and the Peanut ELISA kit, respectively. Reproducibility relative standard deviations of peanut standard protein in four food extracts were 23.5-44.4%, 9.6-28.4% for the Peanut kit and the Peanut ELISA kit, respectively. The detection limits of both ELISA methods were 2-2.5 ng/mL in sample solutions. These results suggested that the notified ELISA methods are reliable and reproducible for the inspection of peanut protein levels in extracts of biscuit, sauce, chocolate and butter.     

全球变暖对日本寒地北海道2030年代水稻生育的影响预测及其对策（网络首发、推荐阅读）

北海道从1980年代开始到2010年代为止,水稻大田栽培期间的5–9月份气温随着年代而不断上升。与最近的2010年代（2010—2019年平均）相比,使用两种2030年代的预测气象,根据以往研究得到的关系方程预测研究了水稻生育。其结果,2030年代比2010年代,插秧日期期限（插秧最早期限）比水稻栽培17个地区平均值要早8~9天。另外,抽穗日期最早期限要早1~5天,抽穗日期最晚期限要晚1~5天,安全抽穗期间要长2~10天,抽穗日期要早1~3天。由于从抽穗日期到最晚抽穗为止要长2~9天,延迟型冷害的发生要略少。关于各生育期的气象,抽穗前24天以后的30天期间的平均气温因为生育早而相同或略低。抽穗前10天以后的40天期间以及抽穗日期以后的40天期间的平均气温略高,日射量略少。因此,糙米产量为96%~98%,要略低,显示潜在产量特性的气候灌浆量指数相同。因为与障碍秕粒发生有关的孕穗期冷害危险期的平均气温略低或基本相同,带来发生冷害的风险。另一方面,引起秕粒发生的低温区的出现频率在地区间具有差异。虽然大米蛋白质含量相同,但直链淀粉含量略低、食味略良。关于米粒外观品质,受害粒比率和着色粒比率没有一定的变化趋势,未熟粒比率略高,大米白度相同,糙米白度略高。通过上述预测研究显示了未来日本寒冷地带水稻生育的技术应对方向。     

Quantitative analyses of the behavior of exogenously added bacteria during an acidulocomposting process

Poly[3-hydroxybutyrate-co-3-hydroxyvalerate(3HV)] was produced in recombinant Escherichia coli LS5218 from ruthenium-catalyzed cellulose hydrolysate and propionate. The strain was found to be resistant to 5-hydroxymethylfurfural (5-HMF), which is a major inhibitory byproduct generated in the cellulose hydrolysis reaction. The 3HV fraction was successfully regulated in the range of 5.6-40 mol%.     

From Terpenoids to Aliphatic Acids: Further Evidence for Late-Instar Switch in Osmeterial Defense as a Characteristic Trait of Swallowtail Butterflies in the Tribe Papilionini

We compared the chemical compositions of the osmeterial secretions of fourth and fifth (last) instars of eight swallowtail species of the tribe Papilionini. Four species (Papilio demoleus, P. polytes, P. paris, and P. macilentus) are Asian Rutaceae-feeding swallowtails. The other four (Chilasa epicydes, C. agestor, P. troilus, and P. glaucus) represent more distant clades within the Papilionini and species with larval hosts in other plant families. We conducted a quantitative analysis for six species, but only qualitative analysis for P. glaucus and C. agestor. In all eight species, regardless of larval host plant, secretions of the fourth instar principally consisted of mono- and sesquiterpene hydrocarbons, whereas those of the fifth instar comprised aliphatic acids and their esters. Consistent with earlier findings, our results suggest that this “heterogeneous” pattern of osmeterial chemistry, not seen in other tribes, may characterize the Papilionini as a whole. Unlike those of most Papilio species, the fourth and fifth instars of Chilasa species resemble each other in body coloration. Thus, the heterogeneous osmeterial pattern is not necessarily associated with color change in papilionid larvae. The major terpenoids identified in fourth instar larval secretions from the six species were α-pinene, sabinene, β-myrcene, limonene, β-phellandrene, (Z)-β-ocimene, (E)-β-ocimene, p-mentha-1,4(8)-diene, β-elemene, β-caryophyllene, (E)-β-farnesene, (3Z,6E)-α-farnesene, (Z)-α-bisabolene, germacrene-A, (E)-α-bisabolene, and germacrene-B. The profiles for individual species differed both qualitatively and quantitatively from one another, and certain species also secreted methyl 3-hydroxy-n-butyrate and oxygenated sesquiterpenes in relatively large proportions. Secretions from fifth instars were composed of varying proportions of isobutyric, 2-methylbutyric, and acetic acids, and methyl and ethyl (minor) esters of both isobutyric and 2-methylbutyric acids. The heterogeneity of osmeterial chemistry in the tribe Papilionini may represent fine-tuning of chemical defense in response to shifting predation pressures as the larvae age and grow.