Nonlinear Energy Response of Glass Forming Materials

A theory for the nonlinear energy response of a system subjected to a heat bath is developed when the temperature of the heat bath is modulated sinusoidally. The theory is applied to a model glass forming system, where the landscape is assumed to have 20 basins and transition rates between basins obey a power law distribution. It is shown that the statistics of eigenvalues of the transition rate matrix, the glass transition temperature $T_g$, the Vogel-Fulcher temperature $T_0$ and the crossover temperature $T_x$ can be determined from the 1st- and 2nd-order ac specific heats, which are defined as coefficients of the 1st- and 2nd-order energy responses. The imaginary part of the 1st-order ac specific heat has a broad peak corresponding to the distribution of the eigenvalues. When the temperature is decreased below $T_g$, the frequency of the peak decreases and the width increases. Furthermore, the statistics of eigenvalues can be obtained from the frequency dependence of the 1st-order ac specific heat. The 2nd-order ac specific heat shows extrema as a function of the frequency. The extrema diverge at the Vogel-Fulcher temperature $T_0$. The temperature dependence of the extrema changes significantly near $T_g$ and some extrema vanish near $T_x$.Comment: 20 pages, 10 figure

歩行者への不適切な横断開始予測に起因するドライバの判断エラーに関する研究

学位の種別: 課程博士審査委員会委員 : （主査）東京大学准教授 小竹 元基, 東京大学教授 須田 義大, 東京大学教授 鎌田 実, 東京大学教授 佐藤 洋一, 産業技術総合研究所センター長 北崎 智之University of Tokyo(東京大学

有限要素法を用いた大規模空間吊り天井の脱落被害再現シミュレーション

Many ceiling collapse damages were observed in wide-area structures such as gymnasiums during the 2011 Great East-Japan Earthquake and the 2016 Kumamoto Earthquake. The prevention of ceiling collapse phenomena is an important issue not only to save people\u27s lives, but to keep these facilities to be safely used as shelters after earthquakes. In this paper, a numerical analysis to simulate the ceiling collapse in a full-scale gymnasium specimen, which was tested at the E-Defense shaking table facility in 2014, was conducted. A numerical model consisted of steel structural frames and suspended ceilings were constructed. All the members were modeled using linear Timoshenko beam elements and the adaptively shifted integration (ASI) - Gauss code was applied. Hangers and hanging bolts were modeled in one piece. The plaster boards were assumed as rigid in out of plane direction and only the mass of rock wool boards was considered. Their strength were neglected. Clips and screws were modeled with minute, small elements. Each plaster board was modeled separately to consider local contact between plaster boards, which was simulated by modeling the screws slightly apart. Elasto-plastic buckling of braces and hanging bolts were considered by modeling them with eight beam elements each and two hinge elements on both ends. The clips connecting ceiling joists and ceiling joist receivers are small and delicate components that may be detached during repeated excitation. Once there is a local detachment of clips, a change in the load distribution may cause a chain reaction of detachments, which ends in a drop of plaster boards. Furthermore, the detachments of hanging bolts that are connected to the structural members composing the roof, and failure of screws on plaster boards are assumed to be other main causes of the ceiling collapse. The results of some preliminary tests conducted to see the actual strength of these components are implemented in the analysis for criteria. The numerical result was validated by the experimental result, which was performed at the E-Defense under an input of two continuous K-NET Sendai 50% waves. The acceleration responses, the spectrum and the displacement responses obtained on the roof matched well with the experimental result. According to the results, the plaster boards near walls pattered down occasionally at the first peak of the first wave. These were due to detachment of clips and screws caused by collisions to the walls. Then, the clips near roof top began to get loose due to buckling of hanging bolts caused by vertical excitation, which ends, at the first peak of the second wave, in drop of plaster boards in a wide range. The numerical result had shown the collapse of the ceilings progressed owing to the detachment of clips that connected the ceiling joists to the ceiling joist receivers, which eventually led to a large-scale collapse of the ceilings

Expressions of Vascular Endothelial Growth Factor (VEGF)-D and VEGF Receptor-3 in Colorectal Cancer: Relationship to Lymph Node Metastasis

Angiogenic factors play a major role in tumor growth and metastasis. Vascular endothelial growth factor (VEGF)- D is a ligand for VEGF receptor-3 (VEGFR-3/Flt-4), which mainly expressed on the lymphatic endothelium. Recent experimental studies have shown that VEGF-D induces tumor lymphangiogenesis and promote metastatic spread of tumor cells via lymphatic vessels. However, the contribution of VEGFD to lymph node metastasis in human colorectal cancer is less understood. We therefore examined VEGF-D and VEGFR-3 expression in patients with colorectal cancer. Sections of formalin-fixed and paraffin-embedded specimens from 76 colorectal cancers were immunohistochemically stained for VEGF-D and VEGFR-3. Staining for VEGF-D was positive in the cytoplasm of tumor cells in 43 of 76 examined tumors (56.6%). Staining for VEGFR-3 was positive in endothelial cells in 38 (50.0%) tumors. Univariate analysis showed that both VEGF-D and VEGFR-3 expressions correlated significantly with lymph node metastasis, histological type and depth of tumor invasion. However, logistic regression analysis indicated that VEGF-D expression, but not that of VEGFR-3, was an independent predictor for lymph node metastasis. Our data suggest that VEGF-D plays an important role in lymph node metastasis in colorectal cancer

Identification of amino acids in antigen-binding site of class II HLA proteins independently associated with hepatitis B vaccine response

Background & aimsGenetic factors in class II human leukocyte antigen (HLA) have been reported to be associated with inter-individual variation in hepatitis B virus (HBV) vaccine response. However, the mechanism underlying the associations remains elusive. In particular, the broad linkage disequilibrium in HLA region complicates the localization of the independent effects of genetic variants. Thus, the present study aimed to identify the most probable causal variations in class II HLA loci involved in the immune response to HBV vaccine.MethodsWe performed a case-control study to assess whether HLA-DRB1, -DQB1, and -DPB1 4-digit alleles were associated with the response to primary HBV vaccination in 574 healthy Japanese students. To identify causative variants, we next assessed independently associated amino acid variants in these loci using conditional logistic regression analysis. Furthermore, to clarify the functional effects of these variants on HLA proteins, we performed computational structural studies.ResultsHLA-DRB1∗01:01, HLA-DRB1∗08:03, HLA-DQB1∗05:01, and HLA-DPB1∗04:02 were significantly associated with sufficient response, whereas HLA-DPB1∗05:01 was associated with poor response. We then identified amino acids independently associated with sufficient response, namely, leucine at position 26 of HLA-DRβ1 and glycine-glycine-proline-methionine at positions 84–87 of HLA-DPβ1. These amino acids were located in antigen-binding pocket 4 of HLA-DR and pocket 1 of HLA-DP, respectively, which are important structures for selective binding of antigenic peptides. In addition, the detected variations in HLA-DP protein were responsible for the differences in the electrostatic potentials of the pocket, which can explain in part the sufficient/poor vaccine responses.ConclusionHLA-DRβ1 position 26 and HLA-DPβ1 positions 84–87 are independently associated with anti-HBs production against HBV vaccine. Our results suggest that HBsAg presentation through these HLA pocket structures plays an important role in the inter-individual variability of HBV vaccination

Numerical Chromosome Aberrations In A Recurrent Malignant Fibrous Histiocytoma of the Retroperitoneum

Malignant fibrous histiocytoma (MFH) of the retroperitoneum is relatively rare in Japan. MFHs often recurs even if the tumor is resected completely. We describe a case with recurrent MFH of the retroperitoneum. A 49-year-old male was-admitted to our hospital for a palpable mass in the right lower abdomen. Ultrasonography and computed tomography demonstrated a solid mass with cystic compartment in the lower pole of the right kidney. The tumor was resected completely, and histological examination showed it was MFH, storiform-pleomorphic type. Thirty-three months later, a local recurrence developed and a second operation was performed. The resected tumor was 4.5 ﾃ・3.9 ﾃ・3.1 cm in size and histological diagnosis was recurrent MFH. We also examined the cytological characteristics of the tumor, using DNA flow cytometric quantification and fluorescence in situ hybridization (FISH) with a set of 14 chromosomespecific DNA probes. DNA contents showed a DNA diploid pattern, however, FISH analysis showed various aberrations of chromosome number such as +1, +2, +7, +8, -10, +11, +12, -16, -17, -18, and +20. These results suggested that chromosomal aberrations may reflect a higher biologic aggressiveness of recurrent MFH

Elevated Expression of Poly(ADP-Ribose) Polymerase-1 is Associated with Liver Metastasis in Colorectal Cancer.

Activation of poly(ADP-ribose) polymerase-1 (PARP-1) and its subsequent cleavage are early markers of apoptosis. PARP-1 is associated with DNA repair and so chromosome stability, cell cycle regulation, as well as tumorigenesis. To investigate the role of PARP-1 expression in colorectal carcinoma and its metastasis of liver, we compared the expression of PARP-1 in primary colorectal cancers with (n=15) and without liver metastasis (n=17) using a semi-quantitative reverse transcription - polymerase chain reaction. We also examined the expressions of poly(ADP-ribose) (PAR) and p53 in these tumors by immunohistochemistry. A significantly higher PARP-1 mRNA expression was noted in tumors with liver metastasis than those without liver metastasis (p<0.01). Colorectal cancers positively stained for p53 exhibited significantly higher PARP-1 mRNA expression than p53-negative tumors (p<0.01). The PAR labeling index (LI) of tumors with metastasis (0.33 ﾂｱ 0.33) was not significantly different (p=0.35) from that of tumors without liver metastasis (0.38 ﾂｱ 0.19). p53-positive tumors tended to have higher PAR LI levels than p53-negative tumors (p=0.08). Our findings suggest that PARP-1 may contribute to liver metastasis due to its DNA repair activity, resulting in survival of the tumor cells with accumulation of metastaticrelated gene\u27s damages. Detailed analysis of PARP-1 may be useful in cancer research and/or cancer therapy

Implantable CMOS Biomedical Devices

The results of recent research on our implantable CMOS biomedical devices are reviewed. Topics include retinal prosthesis devices and deep-brain implantation devices for small animals. Fundamental device structures and characteristics as well as in vivo experiments are presented

Influenza A (H5N1) Viruses from Pigs, Indonesia

TOC summary: Pigs may serve as intermediate hosts in which this avian virus can adapt to mammals

Magnifying Colonoscopy Findings for Differential Diagnosis of Sessile Serrated Adenoma/Polyps and Hyperplastic Polyps

Sessile serrated adenoma/polyps (SSA/Ps) are thought to be precursors of colorectal cancers. However, current endoscopic techniques for differentiating SSA/Ps from conventional hyperplastic polyps (HPs) have low diagnostic accuracy. The aim of the present study was to assess the ability of mucosal crypt patterns to distinguish SSA/Ps from HPs. We examined 140 lesions from 93 patients that had been diagnosed histologically as SSA/Ps or HPs at the Showa University Hospital between June 2010 and May 2012. Three experienced colonoscopists reviewed the endoscopic findings of magnifying colonoscopy. Type II open-shape (Type II-O) pit patterns and varicose microvascular vessels (VMVs) were identified according to previously proposed definitions. Although 140 lesions were initially identified for the study, 27 lesions were excluded from analysis because of insufficient endoscopic findings. Thus, endoscopic findings from a total of 113 lesions (68 SSA/Ps and 45 HPs) were evaluated. Of 113 serrated polyps, 51 lesions (44 SSA/Ps and 7 HPs; P<0.01) had Type II-O pit patterns. The inter- and intra-observer agreement for these patterns among three colonoscopists was κ=0.61 (range 0.57–0.65) and κ=0.68 (range 0.52–0.94), respectively. The positive predictive value (PPV), negative predictive value (NPV), sensitivity, and specificity of Type II-O pit patterns for differentiating between SSA/P and HP were 86%, 61%, 65%, and 84%, respectively. In contrast, the PPV, NPV, sensitivity, and specificity of VMVs were 68%, 43%, 37%, and 73%, respectively. The results indicate that Type II-O mucosal crypt patterns may be useful for the differential diagnosis of SSAPs and HPs