統合化された海溝型巨大地震リスク評価に関する研究

京都大学新制・論文博士博士(工学)乙第13406号論工博第4192号新制||工||1762(附属図書館)(主査)教授 松島 信一, 教授 竹脇 出, 教授 牧 紀男学位規則第4条第2項該当Doctor of Philosophy (Engineering)Kyoto UniversityDFA

Structures and dynamic viscoelastic properties of micelles of mixtures of surfactin with cationic surfactant in aqueous solution

Surfactin sodium salt (SFNa) consisting of a long alkyl chain and cyclic peptide is a biosurfactant produced by Bacillus subtilis. SFNa is expected to be a useful material in cosmetics, medical field, and so on because it shows unique surface activities such as significant reduction of surface tension at extremely dilute concentration. In our previous study, we found SF formed monodisperse spherical micelles with low aggregation number in aqueous solution [1]. In addition, the aggregation number of SF micelles was discretely changed with varying salt concentration. However, such small changes of micelle structures cause slight change in viscoelasticity of the micelle solution. In the case that SF is used in detergent, tuning viscoelastic properties of its solution is requested. To tune the viscoelastic properties, tuning the structures of micelles should be important Mixing of anionic and cationic surfactant is one of the effective method to tune the structures of micelles. Therefore, addition of a cationic surfactant to anionic SFNa is expected to cause drastic change in viscoelastic properties owing to structural changes of SF micelles. Thus, in this study, we investigate the structures of micelles consisting of anionic SFNa and cetyltrimethyl ammonium bromide (CTAB) as a cationic surfactant and their viscoelasticity related to the structures of micelles. SFNa was provided by Kaneka Corporation and CTAB was dissolved at desired surfactant concentration, mole fraction of SFNa (XSF) and ratio of cation to anion (C/A) in aqueous NaCl solution. For the resulting SFNa-CTAB micelle solutions, visual observation, small angle X-ray scattering (SAXS) and dynamic viscoelastic analyses measurements were performed. We found that viscosity of aqueous solutions of SFNa-CTAB micelles are increased with increasing SF content in XSF \u3c 0.2 and CTAB content in 0.65 XSF \u3e 0.5. Therefore, it should be considered that structures of mixed micelles in these regions are much different from those of SFNa or CTAB micelles. Figure 1 shows SAXS profiles of SF-CTAB micelles at XSF = 0.1 (Red) and 0.6 (Blue). It could be confirmed scattering intensities in both systems are proportional to q-1 at low q range. Therefore, SF-CTAB mixtures form worm-like micelles at XSF = 0.1 and 0.6. However, SAXS profiles of these micelles are much different in high q region. Consequently, these micelles have different interiors. Thus, to investigate the effect of such structural difference of micelles on viscoelastic properties, dynamic viscoelastic measurements were performed. Figure 2 shows concentration dependences of the terminal relaxation times (τs) of SFNa-CTAB micelles at XSF = 0.1 and 0.6 obtained from the analyses for frequency dependence of storage and loss moduli by using Maxwell model. The τSs of these micelles are almost constant against micelle concentrations. This result means the entanglements of worm-like micelles of SFNa-CTAB mixtures are regarded as transient networks. References 1. Fujii, S. et al., Scientific Reports 2017, 7, 44494. 2. Naruse, K. et al., J. Phys. Chem. B. 2009, 113, 10222-10229 Please click Additional Files below to see the full abstract

Subsurface structure identification at the blind prediction site of ESG6 based on the earthquake-to-microtremor ratio method and diffuse field concept for earthquakes

We participated in the blind prediction exercise organized by the committee of the blind prediction experiment during the 6th International Symposium on Effects of Surface Geology on Seismic Motion (CBP-ESG6). In response to the committee's request, we identified the ground velocity structure from microtremors observed at a target site as the first step of the exercise. First, we calculated the horizontal-to-vertical spectral ratio of microtremors (MHVR) at the target site from the distributed microtremor data collected in the vicinity of the target site in Kumamoto Prefecture. Then, we converted the MHVR into a pseudo horizontal-to-vertical spectral ratio of earthquake (pEHVR) using the previously proposed and validated earthquake-to-microtremor ratio (EMR) method, where an empirically obtained EMR is used to convert MHVR into pEHVR. Next, we inverted the S-wave and P-wave velocity structures based on the pEHVR and the diffuse field concept for earthquakes. The theoretical EHVR calculated from the identified velocity structure reproduced the pEHVR quite well in the frequency range of 0.1-22 Hz. After the collection of the blind prediction results by all the participants, the CBP-ESG6 released the observed earthquake records, a preferred model based on the P-S logging data from the in-situ borehole measurement combined with the generic deeper structure, and the average of all the predicted structures by the participants. Notably, our inverted structure was found to be close to the preferred model and the averaged one of all the blind prediction participants, despite some minor differences in the horizontal site amplification factor around the maximum peak frequency at 0.8-1 Hz

Characterization of genetically modified mice for phosphoglycerate mutase, a vitally-essential enzyme in glycolysis

Models de ratolí; Glucòlisi; Diabetis mellitusModelos de ratón; Glucólisis; Diabetes mellitusMouse models; Glycolysis; Diabetes mellitusGlycolytic metabolism is closely involved in physiological homeostasis and pathophysiological states. Among glycolytic enzymes, phosphoglycerate mutase (PGAM) has been reported to exert certain physiological role in vitro, whereas its impact on glucose metabolism in vivo remains unclear. Here, we report the characterization of Pgam1 knockout mice. We observed that homozygous knockout mice of Pgam1 were embryonic lethal. Although we previously reported that both PGAM-1 and -2 affect global glycolytic profile of cancers in vitro, in vivo glucose parameters were less affected both in the heterozygous knockout of Pgam1 and in Pgam2 transgenic mice. Thus, the impact of PGAM on in vivo glucose metabolism is rather complex than expected before.This work was supported in part by grants from the Japan Society for the Promotion of Science (Grants No. 26310103 to HK and No. 15K19283 to HK), and by the Japan Agency for Medical Research and Development (AMED), Core Research for Evolutional Science and Technology (CREST JP17gm0610002h0306 to HK). HK; Hiroshi Kondoh

Texture analysis of low-flow vascular malformations in the oral and maxillofacial region : venous malformation vs. lymphatic malformation

Purpose: It is challenging for radiologists to distinguish between venous malformations (VMs) and lymphatic malformations (LMs) using magnetic resonance imaging (MRI). Thus, this study aimed to differentiate VMs from LMs using non-contrast-enhanced MRI texture analysis. Material and methods: This retrospective case-control study included 12 LM patients (6 men and 6 women; mean age 43.58, range 7-85 years) and 29 VM patients (7 men and 22 women; mean age 53.10, range 19-76 years) who underwent MRI for suspected vascular malformations. LM and VM patients were identified by histopathological examination of tissues excised during surgery. The texture features of VM and LM were analysed using the open-access software MaZda version 3.3. Seventeen texture features were selected using the Fisher and probability of error and average correlation coefficient methods in MaZda from 279 original parameters calculated for VM and LM. Results: Among 17 selected texture features, the patients with LM and VM revealed significant differences in 1 histogram feature, 8 grey-level co-occurrence matrix (GLCM) features, and 1 grey-level run-length matrix feature. At the cut-off values of the histogram feature [skewness ≤ –0.131], and the GLCM features [S(0, 2) correlation ≥ 0.667, S(0, 3) correlation ≥ 0.451, S(0, 4) correlation ≥ 0.276, S(0, 5) correlation ≥ 0.389, S(1, 1) correlation ≥ 0.739, S(2, 2) correlation ≥ 0.446, S(2, –2) correlation ≥ 0.299, S(3, –3) correlation ≥ 0.091] had area under the curves of 0.724, 0.764, 0.773, 0.747, 0.733, 0.759, 0.730, 0.744 and 0.727, respectively. Conclusions: Non-contrast-enhanced MRI texture analysis allows us to differentiate between LMs and VMs

Method to extract difficult-to-evacuate areas by using tsunami evacuation simulation and numerical analysis

Extracting the area where people have difficulty evacuating (hereafter difficult-to-evacuate areas, DEA) when tsunamis hit after an earthquake is important for effective disaster mitigation measures. The DEA was conven-tionally extracted by simply considering the walking speed, distance to the evacuation destination, and time needed for evacuation after considering the estimated tsunami inundation area. However, evaluating the DEA from such a simple scheme is insufficient because the behavior of residents and the road conditions to the evacuation destinations after an earthquake are not properly reflected in the scheme. In this study, agent-based tsunami evacuation simulations that can reflect the behavior of residents and real -time changes in the situation were conducted in Zihuatanejo, Guerrero, Mexico. It is a prime sightseeing destination under the high risk of megathrust events in the Guerrero Gap. First, by checking the simulation images at the tsunami arrival time, bottleneck locations were identified, and five additional models with different measures for the bottleneck locations were constructed and tested to find the best model with 195 casualties. Then, focusing on the best model, three indices for the casualties were proposed to extract the DEA effectively and quantitatively, and numerical analyses using the three indices was conducted. Finally, the subdistrict in the center of the target area (subdistrict 5) was quantitatively found to be the district that should be given the highest priority for measures. Moreover, an example model with a new measure in subdistrict 5 was validated to have 101 casualties. The key points for applying the proposed method for extraction of DEA in other areas are summarized

外科的に切除しえた, 肝硬変を伴う維持透析患者に発症した右腎癌下大静脈腫瘍塞栓の1例

症例は54歳, 男性。1900年, CGNにて血液透析導入となった。2005年2月に肉眼的血尿が出現。CTにて右腎癌を指摘され, 3月9日当科紹介。当科にて施行したCTでは直径7cm大の右腎腫瘍とともに下大静脈内の肝静脈流入部まで達する腫瘍塞栓を認めた。右腎腫瘍, 下大静脈塞栓, T3bN0M0 stage IIIの診断で4月28日, 根治的右腎摘除ならびに腫瘍塞栓摘除術を施行した。手術時間4時間28分, 出血量1, 400ml, 摘出標本は重量800g, 病理所見はrenal cell carcinoma, G2, pT3bであった。術前の凝固系検査は異常を認めなかったが, 肝硬変が原因と考えられる出血時間の延長と血小板数の低下を認めたため, 周術期は血小板輸血などにて対応した。術後経過は良好で, 後出血などの術後合併症もなく, 術後18日目に退院した。現在IFNα投与にて後療法を施行中であるが, 再発を認めていない。透析患者における下大静脈腫瘍塞栓を伴う腎癌に対して外科的治療を施行した症例についての報告例については比較的少なく, 文献的考察も含めて報告する。(著者抄録)A 54-year-old man who had been under hemodialysis therapy for 16 years presented with gross hematuria at our department in February 2005. Imaging findings revealed right renal tumor of8.2 cm in diameter. In addition, the tumor extended into inferior vena cava at the level of the hepatic vein. There were no findings of distant metastasis. Right radical nephrectomy and thrombectomy were performed on April 2006. Histopathological analysis showed that the tumor was renal cell carcinoma of clear cell type, grade 2. Postoperative course was uneventful, and the adjuvant therapy with interferon alpha was initiated. He has been free from recurrence for 22 months after surgery

Cattle Is Possible Host Animal of The Land Leech (Advanced Studies on Sustainable Animal Production: Interrelationships among Human, Animal and Environment, 8th International Symposium of Integrated Field Science)

Poster Sessio

S-Wave Site Amplification Factors from Observed Ground Motions in Japan: Validation of Delineated Velocity Structures and Proposal for Empirical Correction

We first derived site amplification factors (SAFs) from the observed strong motions by the Japanese nationwide networks, namely, K-NET and KiK-net of National Institute of Earthquake Research and Disaster Resilience and Shindokei (Instrumental Seismic Intensity) Network of Japan Meteorological Agency by using the so-called generalized spectral inversion technique. We can use these SAFs for strong motion prediction at these observation sites, however, we need at least observed weak motion or microtremor data to quantify SAF at an arbitrary site. So we tested the capability of the current velocity models in Japan whether they can reproduce or not the observed SAFs at the nearest grid of every 250 m as the one-dimensional theoretical transfer functions (TTF). We found that at about one-half of the sites the calculated 1D TTFs show more or less acceptable fit to the observed SAFs, however, the TTFs tend to underestimate the observed SAFs in general. Therefore, we propose a simple, empirical method to fill the gap between the observed SAFs and the calculated TTFs. Validation examples show that our proposed method effectively predict better SAFs than the direct substitute of TTFs at sites without observed data

Renoprotective Action of a Matrix Metalloproteinase Inhibitor in Progressive Mesangioproliferative Nephritis

Background/Aim: Matrix metalloproteinases (MMPs) play pivotal roles in extracellular matrix turnover and are involved in chronic kidney disease. The renoprotective action of a synthetic MMP inhibitor, compound A, was investigated in chronic nephritis. Methods: Nephritis was induced by a single injection of anti-Thy1.1 antibody to unilaterally nephrectomized rats. The effects of compound A on proteinuria, blood urea nitrogen, and matrix-related gene expressions were evaluated. Collagen accumulation, as assessed by periodic acid-Schiff staining and hydroxyproline content, was determined. The integrity of glomerular epithelial cells and glomerular basement membrane was evaluated with desmin immunohistochemistry and electron microscopic detection of anionic charge sites, respectively. Results: Treatment with compound A notably attenuated proteinuria, ameliorated blood urea nitrogen, and prevented glomerulosclerosis. Gene upregulation of collagen and transforming growth factor β1 in the cortex was prevented in the treated animals. Glomerular epithelial cell injury was milder, and glomerular basement membrane anionic sites were protected with the treatment. Conclusion: A novel MMP inhibitor, compound A, exerts protective effects in progressive glomerulonephritis. Compound A ameliorates various aspects of renal injuries and may have therapeutic potential toward kidney diseases