Heat transfer in natural convection with finite-sized particles considering thermal conductance due to inter­particle contacts

This is a pre-copyedited, author-produced PDF of an article accepted for publication in Computational Thermal Sciences following peer review

Constraining the source of the Mw 8.1 Chiapas, Mexico earthquake of 8 September 2017 using teleseismic and tsunami observations

The September 2017 Chiapas (Mexico) normal- 6 faulting intraplate earthquake (Mw 8.1) occurred within the 7 Tehuantepec seismic gap offshore Mexico. We constrained the 8 finite-fault slip model of this great earthquake using teleseismic and 9 tsunami observations. First, teleseismic body-wave inversions were 10 conducted for both steep (NP-1) and low-angle (NP-2) nodal planes 11 for rupture velocities (Vr) of 1.5–4.0 km/s. Teleseismic inversion 12 guided us to NP-1 as the actual fault plane, but was not conclusive 13 about the best Vr. Tsunami simulations also confirmed that NP-1 is 14 favored over NP-2 and guided the Vr = 2.5 km/s as the best source 15 model. Our model has a maximum and average slips of 13.1 and 16 3.7 m, respectively, over a 130 km 9 80 km fault plane. Coulomb 17 stress transfer analysis revealed that the probability for the occur- 18 rence of a future large thrust interplate earthquake at offshore of the 19 Tehuantepec seismic gap had been increased following the 2017 20 Chiapas normal-faulting intraplate earthquake

Identification of protease serine S1 family member 53 as a mitochondrial protein in murine islet beta cells

The aim of this study was to identify genes that are specifically expressed in pancreatic islet β-cells (hereafter referred to as β-cells). Large-scale complementary DNA-sequencing analysis was performed for 3,429 expressed sequence tags derived from murine MIN6 β-cells, through homology comparisons using the GenBank database. Three individual ESTs were found to code for protease serine S1 family member 53 (Prss53). Prss53 mRNA is processed into both a short and long form, which encode 482 and 552 amino acids, respectively. Transient overexpression of myc-tagged Prss53 in COS-7 cells showed that Prss53 was strongly associated with the luminal surfaces of organellar membranes and that it underwent signal peptide cleavage and N-glycosylation. Immunoelectron microscopy and western blotting revealed that Prss53 localized to mitochondria in MIN6 cells. Short hairpin RNA-mediated Prss53 knockdown resulted in Ppargc1a downregulation and Ucp2 and Glut2 upregulation. JC-1 staining revealed that the mitochondria were depolarized in Prss53-knockdown MIN6 cells; however, no change was observed in glucose-stimulated insulin secretion. Our results suggest that mitochondrial Prss53 expression plays an important role in maintaining the health of β-cells

Advances in 5-ALA-PDD of gastric cancer

Photodynamic diagnosis based on 5-aminolevulinic acid-induced protoporphyrin IX has been clinically applied in many fields based upon its evidenced efficacy and adequate safety. In order to establish a personalized medicine approach for treating gastric cancer patients, rapid intraoperative detection of malignant lesions has become important. Feasibility of photodynamic diagnosis using 5-aminolevulinic acid for gastric cancer patients has been investigated, especially for the detection of peritoneal dissemination and lymph node metastasis. This method enables intraoperative real-time fluorescence detection of peritoneal dissemination, exhibiting higher sensitivity than white light observation without histopathological examination. The method also enables detection of metastatic foci within excised lymph nodes, exhibiting a diagnostic accuracy comparable to that of a current molecular diagnostics technique. Although several complicating issues still need to be resolved, such as the effect of tissue autofluorescence and the insufficient depth penetration of excitation light, this simple and rapid method has the potential to become a useful diagnostic tool for gastric cancer, as well as urinary bladder cancer and glioma

Label-free Evaluation of Myocardial Infarct in Surgically Excised Ventricular Myocardium by Raman Spectroscopy

Understanding the viability of the ischemic myocardial tissue is a critical issue in determining the appropriate surgical procedure for patients with chronic heart failure after myocardial infarction (MI). Conventional MI evaluation methods are; however, preoperatively performed and/or give an indirect information of myocardial viability such as shape, color, and blood flow. In this study, we realize the evaluation of MI in patients undergoing cardiac surgery by Raman spectroscopy under label-free conditions, which is based on intrinsic molecular constituents related to myocardial viability. We identify key signatures of Raman spectra for the evaluation of myocardial viability by evaluating the infarct border zone myocardium that were excised from five patients under surgical ventricular restoration. We also obtain a prediction model to differentiate the infarcted myocardium from the non-infarcted myocardium by applying partial least squares regression-discriminant analysis (PLS-DA) to the Raman spectra. Our prediction model enables identification of the infarcted tissues and the non-infarcted tissues with sensitivities of 99.98% and 99.92%, respectively. Furthermore, the prediction model of the Raman images of the infarct border zone enabled us to visualize boundaries between these distinct regions. Our novel application of Raman spectroscopy to the human heart would be a useful means for the detection of myocardial viability during surgery

Accumulation of Uroporphyrin I in Necrotic Tissues of Squamous Cell Carcinoma after Administration of 5-Aminolevulinic Acid

5-aminolevulinic acid (5-ALA)-induced protoporphyrin IX (PpIX) fluorescence is widely used for the intraoperative detection of malignant tumors. However, the fluorescence emission profiles of the accompanying necrotic regions of these tumors have yet to be determined. To address this, we performed fluorescence and high-performance liquid chromatography (HPLC) analyses of necrotic tissues of squamous cancer after 5-ALA administration. In resected human lymph nodes of metastatic squamous cell carcinoma, we found a fluorescence peak at approximately 620 nm in necrotic lesions, which was distinct from the PpIX fluorescence peak at 635 nm for viable cancer lesions. Necrotic lesions obtained from a subcutaneous xenograft model of human B88 oral squamous cancer also emitted the characteristic fluorescence peak at 620 nm after light irradiation: the fluorescence intensity ratio (620 nm/635 nm) increased with the energy of the irradiation light. HPLC analysis revealed a high content ratio of uroporphyrin I (UPI)/total porphyrins in the necrotic cores of murine tumors, indicating that UPI is responsible for the 620 nm peak. UPI accumulation in necrotic tissues after 5-ALA administration was possibly due to the failure of the heme biosynthetic pathway. Taken together, fluorescence imaging of UPI after 5-ALA administration may be applicable for the evaluation of tumor necrosis

Development of molecular distribution analysis method of color pigments on Japanese woodblock prints by Raman spectral-imaging

錦絵をはじめとする多色摺木版画において，色材は木版画を特徴付ける重要な要素である．そのため，色材の分子構造および分子分布の詳細な解析が実現されれば，江戸時代の錦絵制作過程の重要な一部を推察することができる可能性がある．そこで本研究では，分子構造を強く反映した情報が得られるラマン散乱分光法に着目し，色材の分子構造と空間分布を同時に解析が可能な非侵襲的色材解析法の開発を行った．その結果，ラマン散乱分光法を用いることで色材の分子構造解析およびその空間分布を可視化することに成功した．特に，紙面内イメージングから紙の繊維上の色材分布を可視化することに成功した．また，紙面と垂直方向のイメージングから，色材の立体的空間分布を可視化することに成功した．さらに，膠含有/不含色材の空間分布の違いも明らかにし，色材分布に基づく摺刷技術解析の可能性を示した．以上の結果から，本手法は多色摺木版画制作技法の新たな解析手法となると考えられる．Ukiyo-e prints, Japanese multicolor woodblock prints, is a traditional Japanese art that has been flourished since Edo period. To surmise the production technologies of woodblock prints, such as materials, carving technologies, and printing technologies, detailed analysis of color pigments that are one of the most important essential materials used in woodblock prints is required. In this study, we proposed a noninvasive analytical method of color pigments by means of Raman spectral-imaging. Pigment species and its molecular structures were clarified via Raman spectra of pigments. Raman imaging of woodblock prints revealed pigment distribution in plane and cross-section, which provided adhesion states of pigments on paper fibers. We also visualized a different pigment distribution on paper depending on glue content in pigment mixture. Our results indicated that Raman spectral-imaging would be a promising technique for evaluating a production technologies of ancient ukiyo-e prints that was still unknown at present

偏光分解顕微鏡を用いたアルコール性肝線維症の線維化の量的・質的評価系の開発

Liver fibrosis is assessed mainly by conventional staining or second harmonic generation (SHG) microscopy, which can only provide collagen content in fibrotic area. We propose to use polarization-resolved SHG (PR-SHG) microscopy to quantify liver fibrosis in terms of collagen fiber orientation and crystallization. Liver samples obtained from autopsy cases with fibrosis stage of F0–F4 were evaluated with an SHG microscope, and 12 consecutive PR-SHG images were acquired while changing the polarization azimuth angle of the irradiated laser from 0° to 165° in 15° increments using polarizer. The fiber orientation angle (φ) and degree (ρ) of collagen were estimated from the images. The SHG-positive area increased as the fibrosis stage progressed, which was well consistent with Sirius Red staining. The value of φ was random regardless of fibrosis stage. The mean value of ρ (ρ-mean), which represents collagen fiber crystallinity, varied more as fibrosis progressed to stage F3, and converged to a significantly higher value in F4 than in other stages. Spatial dispersion of ρ (ρ-entropy) also showed increased variation in the stage F3 and decreased variation in the stage F4. It was shown that PR-SHG could provide new information on the properties of collagen fibers in human liver fibrosis