With the recent increase in demand for biodegradable plastics triggered by the microplastics problem, the reuse of waste is also attracting attention. For example, VTT Technical Research Centre of Finland holds a patent to produce high-purity oligo(lactic acid) (

) from polylactic acid waste. If a new useful strain capable of assimilating the can be discovered, it will be possible to produce useful substances from polylactic acid-based waste. For that purpose, it is necessary to clarify the relationship between bacteria and the . As part of this, we tried to analyze the hydrolysis behavior of oligo(lactic acid) using reverse-phase HPLC. From the results, it was shown that the addition of trifluoroacetic acid (TFA) to the HPLC eluent significantly suppressed the broadening of the peaks derived from the , enabling the quantification of . The analytical method will be useful for investigating the effects of useful bacteria on the .

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酸化度の異なるLAを, ラットに, 0.01ml/100g体重/日の割で, 6か月間投与し, 血清中の脂質およびたん白質量の変動について, 臨床栄養学的な面から検討し, 以下の結果を得た。
1) 血清中の総コレステロールおよびリン脂質量は428栄養と食糧No. 3酸化リノール酸 () 投与群およびNo. 4投与群でいずれも有意な増加 (p<0.01) を認めた。 血清中の総脂質量には, いずれの投与群も顕著な変動は認められなかった。
2) 血清中の総たん白質量はNo. 3 投与群およびNo. 4 投与群でいずれも有意な増加 (p<0.01) を認めた。 アルブミンの割合はいずれの投与群も軽度な増減が認められたが有意なものではなかった。 グロプリンの割合は酸化度の高い投与群ほど減少傾向を示し, No. 3 投与群 (p<0.05) およびNo. 4 投与群 (p<0.01) と0いずれも有意な減少を認めた。 アルプミン/グロプリン (A/G) の比率は酸化度の高い投与群ほど増加傾向を示し, No. 4 投与群で有意な増加 (p<0.05) を認めた。 また, No. 4投与群でアルプミンより低分子側に未知たん白質を認め, その割合は, 血清たん白質量の16.5%であった。
3) 血清中のグルタミン酸-オキザロ酢酸トランスアミナーゼおよびグルタミン酸-ピルビン酸トランスアミナーゼ活性は酸化度の高い投与群ほど増加し, 逆に, アルカリフォスファターゼ活性は低下した。
4) 血清中のマロンジアルデヒド量は酸化度の高い投与群ほど増加し, 逆に, 総トコフェロール量は減少した。

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A novel β-cyclodextrin (β-CD) derivative modified with a degradable and biocompatible oligo(lactic acid) () group, 6-oligo(lactic acid)cyclomaltoheptaose (6--β-CD), was successfully synthesized and used as a chiral selector for the capillary electrophoretic (CE) resolution (R_s) of several basic analytes. The primary purpose of the research was to explore the capability of the 6--β-CD as a chiral selector for comparisons with β-CD and HP-β-CD. Substitution with the oligo(lactic acid) group at the sixth hydroxyl sites of the CD is aimed at influencing the magnitude and selectivity of the analyte-CD interactions. The chiral resolution was strongly influenced by the concentration of the CDs and buffer pH. The effects of the substitution degree (DS) and the chain length (n) of the 6-oligo(lactic acid) groups of 6--β-CD on separations were also investigated.

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Purpose: To evaluate the substrate masking ability of different ceramic systems used for complete crowns and assess the influence of their association with an opaque resin-based luting agent (

).

Methods: Eleven ceramic groups were tested (n = 10). Bilayer groups were: ZrPc — zirconia + porcelain; CAD-onHT — zirconia + high translucent lithium disilitace; CAD-onLT — zirconia + low translucent lithium disilicate; LDPc — high opaque lithium disilicate + porcelain. Monolithic groups were: TZ — high translucent zirconia; TLS — translucent, zirconia-reinforced lithium silicate; HTLS — high translucent, zirconia-reinforced lithium silicate; LTLD — low translucent lithium disilicate; HTLD — high translucent lithium disilitace; LGC — leucite-reinforced glass ceramic; FC — feldsphatic ceramic. The substrates adopted were resin composites shaded A1 (control), A3.5 and C4; coppery and silvery metals. Color differences (ΔE₀₀) and translucency parameter (TP₀₀) were assessed with the CIEDE2000 formula. ΔE₀₀ was obtained assessing the ceramic influence only and in association with

.

Results: Zirconia groups presented lower ΔE₀₀ and TP₀₀. CAD-on structures associated to

led to the lower ΔE₀₀ when tested over metals. ΔE₀₀ for LDPc were similar to zirconia when associated to . Monolithic groups presented significant higher ΔE₀₀ and TP₀₀ compared to bilayers, with ΔE₀₀ below the acceptability threshold only when associated to over substrate shade A3.5.

Conclusions: Ceramic type and the white-opaque resin-based luting agent presented a significant effect on the substrate masking ability. All the discolored substrates tested are adequately masked with veneered zirconia or with LDPc (preferably associated to

). The CAD-on technique associated with improved the masking ability over metallic substrates.

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An electrochemical sensor based on a three-dimensional (3D) graphene/carbon nanotube (G/CNT) hybrid was developed for the sensitive detection of olaquindox (

). 3D G/CNT hybrid through covalent C-C bonding was fabricated by one-step synthesis using catalytic chemical vapor deposition. To construct the base of the sensor, a novel composite was fabricated by a functionalized 3D G/CNT with poly-(dimethy diallyl ammonium chloride) and Nafion via simple grind and ultrasonication dispersion methods. The electrochemical determination of exhibited an oxidation peak at −0.685 V with a higher current response. Due to the effective surface area and active sites, a good linear relationship was observed between the concentration and peak current over the range of 1.5 × 10⁻⁶–2.7 × 10⁻³ mg mL⁻¹ with a detection limit of 6.12 × 10⁻⁸ mg mL⁻¹ (3σ). The proposed electrochemical sensor was used to detect in swine samples at a recovery ranging from 97.78% to 104.25%, which exhibits a broader prospect to supervise animal products and a high potential for food security applications.

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Tissue regeneration using biodegradable scaffolds such as poly(L–lactic acid) (PLLA) has been attracting great attention as a new alternating strategy to the artificial organs and organ transplantation. However, PLA is not necessarily an ideal substance for the scaffold from the viewpoint of the cell–compatibility and selectivity. Moreover, it is quite difficult to modify the PLA surfaces because of the lack of side functional groups. In the present study, we developed a novel immobilization method of bioactive molecules onto PLLA nanofiber membrane. Amphiphilic block oligomers probes composed of oligo(lactic acid) () and bioactive peptides were newly synthesized (–peptide), and a small amount of the synthesized –peptides was added to PLA solution before fabricating the PLA nanofiber membrane in order to impart the specific cell adhesion property. The amphiphilic peptides were proved to distribute evenly and stably in the nanofibers due to the hydrophobic interaction with PLA and to improve the cell adhesion property. In addition, nanofiber membrane conduits for nerve tissue regeneration was developed and evaluated in vitro and in vivo.

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Aim: Research suggests that sex may condition atherosclerosis development against different genetic backgrounds. This study addresses the hypothesis that this effect would be exerted by changes in the different apolipoproteins present in high-density lipoproteins.
Methods: ApoE-deficient mice of both sexes with 129 and C57BL/6J genetic backgrounds were fed a chow diet for 14 weeks. At the end of the dietary intervention, the development of atherosclerotic lesions, apolipoproteins, lipid metabolism, inflammation and paraoxonase were assessed.
Results: Differences between atherosclerotic lesions in 129 and C57BL/6J strains of apoE-deficient mice were sex-dependent and were only statistically significant in females. Plasma levels of HDL cholesterol and apolipoproteins related to these lipoparticles, such as apoA-I, apoA-II, apoA-IV, apoA-V and apoJ, were significantly different between these two strains and there were sex-related differences in some of these apolipoproteins. Hepatic steatosis was also related to the strain and was independent of sex. In females, changes in HDL cholesterol and apolipoproteins A-I and A-II were important determinants of atherosclerosis, while this was not the case in males.
Conclusions: Our results demonstrate that atherosclerosis-related differences between 129 and C57BL/6J genetic backgrounds in apoE-deficient mice are sex-dependent and that this finding is explained by the differences in HDL cholesterol and its apolipoprotein components, mainly apoA-I and A-II. Overall, our findings highlight the importance of taking sex into account in the analysis of atherosclerosis and lipid metabolism in animal models.

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The present contribution is centered on the research of cognitive processes and decision making performed in the Risk Analysis and Decision Research Unit at Stockholm University. Methodological aspects of the study of judgment and decision making as cognitive processes are presented in the paper. The process perspective includes a presentation of Differentiation and Consolidation Theory of human decision making which differs from most contemporary decision theories. Empirical results collected over the years and covering problem solving, judgment and decision processes can also be found in the article. The last section presents some issues which are important for future research on human decision processes.

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Impact loads are considered in nuclear facility design as the result of the loading effects of certain design basis accidents and design basis threats made up of natural as well as man-made hazards. Also, beyond design basis accidents and threats are considered. Typical missiles include objects caused by tornado winds, aircrafts, war or terrorist activities, dropped objects, turbine fragments and other missiles resulting from failure of rotating equipment and whipping pipes and other objects of failure of pressurized fluid systems. The aim of the work is to study the potential of tools for numerical simulations to study the local load effects of airplane missiles impacting concrete structures. Two of the leading commercial computer codes for analysis of highly dynamic events, ABAQUS/Explicit and AUTODYN, have been evaluated. Numerical simulations have been carried out for rigid as well as deformable missiles with the characteristics of airplane engines. The analysis results have been compared with test results from a test program performed in the USA at Sandia National Laboratory and in Japan at Kobori Research Complex and Central Research Institute of the Electric Power industry. Finally, numerical simulations of a large passenger airliner impacting a reactor containment has been carried out using the analysis methodology developed.

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For solving inverse problems in computed tomography (CT), we have presented a continuous-time image reconstruction (CIR) system described by a switched nonlinear dynamical system with a piecewise smooth vector field. Recently, we have also proposed an extended CIR (ECIR) system with a modification of the nonlinear vector field, for the purpose of solving inverse problems in binary tomography, which is the process of reconstructing a binary image from a finite number of projections. In this study, we show, by means of numerical experiments, that the ECIR system is effective not only for binary tomography, but also for continuous tomography, such that the maximum pixel value to be reconstructed is previously given. For projection data with insufficient views, we found that the ECIR system exhibited a better convergence performance than the maximum-likelihood expectation-maximization method.

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To discretize a nonlinear differential equation, we have previously proposed a hybrid method constructed as a combination of the additive and multiplicative Euler methods. In this study, we formulate the vector field for which the hybrid Euler method is effective. Then, we evaluate the method through numerical and physical experiments for a tomographic dynamical system using, respectively, a sinogram synthesized by a digital phantom and a measured projection acquired from an X-ray computed tomography scanner. We found that the hybrid Euler method has an advantage over both the additive and multiplicative Euler methods.

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We studied a means of synthesizing colloidal nanocrystals (NCs) of β-LiGaO₂, a wide-band gap semiconductor oxide, by reacting lithium hydroxide (LiOH) with gallium tri-iso-propoxide [Ga(OiPr)₃] in benzylamine. This reaction yielded near-stoichiometric β-LiGaO₂ NCs, 4–5 nm in diameter and capped with n-octylamine, which were highly dispersible in an organic solvent. We proposed that the LiOH and Ga(OiPr)₃ reacted via electrophilic attack of Li⁺ on the bridging oxygen of Ga(OiPr)₃ and/or nucleophilic attack of OH⁻ on the α-carbon of Ga(OiPr)₃. This reaction formed Li–O–Ga bonds and contributed to the near-stoichiometry of the resultant β-LiGaO₂ NCs.

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Gene targeting is a powerful method of specifically modifying genes of interest. It has been most consistently successful in the 129 mouse strain, because the embryonic stem (ES) cells of 129 mice are relatively easy to culture. In gene-targeting experiments, the use of ES cell-derived genomic clones as a source of homology arms is desirable, because the genetic variation among mouse strains results in a reduced frequency of homologous recombination. In this study, we generated an arrayed mouse 129/ BAC library derived from E14.1 ES cells, one of the frequently used ES cell lines. More than 135,000 BAC clones with a mean insert size of 110 kb were isolated. This library is estimated to represent a 5.5-fold mouse genome coverage. The BAC clones can be screened within 2 days by PCR. Considering that all 8 loci so far examined are contained in this BAC library, we believe it will be a useful resource for gene targeting studies using E14 ES cells as well as for genome analysis.

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遺伝性出血性毛細血管拡張症(hereditary hemorrhagic telangiectasia ; HHT)は,血管形成異常から鼻出血・毛細血管拡張・AVMを引き起こす常染色体優性遺伝疾患である.その責任遺伝子としてendoglin, activin receptor-like kinase 1の2つが同定されている.近年,HHTの動物モデルとしてendoglinヘテロ接合体(Eng^<+/->)マウスを用いた研究が報告されるようになり, endoglinの血管形成における役割が次第に解明されるようになってきた.今後,基礎・臨床の両面から解析が進むことにより,現時点では不明なHHT患者における重症度・発現時期のheterogeneityのみならず,脳動静脈奇形発生のメカニズムの解明が期待される.

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Orthogonal frequency division multiplexing (OFDM) has been attracting much attention because of its robustness against frequency selective fading. Instead of well-known cyclic prefix (CP) insertion, known training sequence (TS) insertion can be used for OFDM block transmission (called TS-OFDM). In this paper, we propose a new receiver design, which can obtain the frequency diversity gain through the use of frequency-domain equalization (FDE) for TS-OFDM. A conditional bit error rate (BER) analysis of the proposed FDE is presented. The average BER performance of the TS-OFDM signal transmission in a frequency-selective Rayleigh fading channel is evaluated by the Monte-Carlo numerical computation method using the derived conditional BER and is confirmed by computer simulation. Numerical and computer simulation results show the proposed TS-OFDM with FDE improves BER and throughput performance of TS-OFDM compared to the conventional TS-OFDM receiver due to the frequency diversity gain. It is also shown that the proposed TS-OFDM with FDE is more robust against imperfect channel estimation than the conventional TS-OFDM receiver.

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Surface waters along the Kalamazoo River, USA, were examined for occurrence and population trends of fecal indicator bacteria (FIB) with culture-based and culture-independent methods. The two methods recorded discrepancies in FIB counts, with the culture-independent method revealing more consistent numbers between the river sites. FIB cells that hybridized with the ECO1482 probe were highest in the downstream site, while the upstream site recorded higher ENF343 hybridized cells. Spatial and temporal differences in FIB populations were probably attributable to contrasting fecal pollution influences, vegetation type, varying environmental conditions as well as several in-stream factors between the two river sites.

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The simplest method for making a production schedule is dispatch of jobs to idle machine tools. The method has a tendency of making a compact and efficient schedule, however the completion time of a job is not determined till the job is selected as the next job on an idle machine. Then, online scheduling methods have been developed, in which the production schedule is made as a job arrives at a machine. In this paper, an online scheduling method is developed for flexible flow shops under the due-date related criteria. A special feature of the method is to set the target completion time for each job and each stage. By numerical experiments, it is clarified that the method is better than FIFO (First In First Out) rule and especially the performance of the online scheduling is greatly superior to FIFO for the shops with heavy workload.

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A method for calculating the complete expansion of the Glauber amplitude is proposed. A calculation of the complete Glauber amplitude is performed by using wave functions for ^4He and ^6He projectiles, leading to the reaction and elastic differential cross sections in good agreement with experiment. By relating the N-^<12>C profile function to the NN profile function, we derive a new, simple formula to calculate reaction cross sections which requires only nuclear densities as an input.

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