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

胎生期マウスの脳室帯の細胞接着損傷が大脳皮質形成へ与える影響

哺乳類の大脳皮質は6層構造を形成するが,特に胎生期および新生直後に層形成が盛んに進むことが知られている.胎生期の脳室に面する脳室帯において,神経幹細胞は神経前駆細胞を経て神経細胞へ分化し,さらに神経細胞が脳表層方向に移動することで6層構造が形成される(insideout).このことから,胎生期の脳室帯は脳の形成に重要な役割を果たしていると考えられる.本研究は,大脳皮質の形成メカニズムの解析を目的とし,脳室帯の組織構造に変化を与えた場合に,どのように脳形成システムに異常を来たすのか,検討を行った.脳室帯は上皮組織のため,細胞間結合が強固である.そこで,上皮細胞間のカルシウム(Ca^)依存性接着分子であるカドヘリンに着目し,脳室面の細胞間結合の阻害が脳形成に与える影響を観察した.実験手法として,マウス胎生14.5日目の脳室内へ,Ca^を特異的にキレートするEGTA(Ethylene glycol tetraacetic acid)を注入したのち,胎生期および生後の脳組織構造について詳細な解析を行った.解析の結果,高濃度のEGTAの作用により,一部のマウスは脳浮腫をきたした.また脳室の拡大および大脳皮質の菲薄化も認めた.さらに,大脳皮質各層のマーカーであるSATB2(2/3層),Ctip2(5層)を用いた解析から,脳室帯の細胞間接着構造の破壊により,それ以降の神経細胞の新生は減少するが,層構造のinside-outの法則は維持されていることが分かった.これらのことより,脳室帯構造および脳室帯での神経新生が,inside-outの原理に関与している可能性は低いことがわかった.The cerebral cortex of mammals is a structure consisting of six layers. The progression of layer formation is known to be particularly active during the embryonic and immediate postnatal periods. In the ventricular zones, which adjoin the embryonic cerebral ventricles, neural stem cells differentiate first into neuronal precursor cells and then into neurons. The neurons then migrate toward the surface layer of the brain, forming the 6-layered structure (inside-out). The ventricular zones are thus thought to play an important role in the formation of the brain during the embryonic period. We therefore examined how altering the tissue structure of the cerebral ventricular zones results in abnormalities of the brain formation system. Because the ventricular zones consist of epithelial tissue, the cell junctions are rigid. Consequently, we observed the effect on brain formation of disrupting cell junctions on the ventricular surface, focusing on cadherins, which are calcium (Ca^)-dependent adhesion molecules between epithelial cells. The experimental method involved injecting ethylene glycol tetraacetic acid (EGTA), which specifically chelates Ca^, into the cerebral ventricles of 14.5-day-old mouse embryos, then analyzing the tissue structure of the brain in the embryonic and postnatal periods in detail. The results showed that EGTA at high concentration resulted in cerebral edema in some mice. Enlargement of the cerebral ventricles and thinning of the cerebral cortex were also observed. In addition, analysis using SATB2 as a marker of layers 2 and 3 and Ctip2 as a marker of layer 5 showed that although subsequent neurogenesis decreased with the breakdown of the adhesive structure of the ventricular zones, the inside-out rule was maintained for the layer structure. These findings show that the ventricular zone structure and neurogenesis in the ventricular zones are unlikely to play a role in the mechanism underlying the inside-out principle

Successful stenting of the ductus venosus in 2 neonates with asplenia syndrome complicated by infracardiac type total anomalous pulmonary venous connection

SummaryIn the neonatal period, the surgical mortality of palliation is extremely high for asplenia syndrome complicated by single ventricle combined with total anomalous pulmonary venous connection (TAPVC). Recently, stent implantation for the pulmonary venous drainage route soon after birth has been used instead of surgery to prevent pulmonary venous occlusion and to maintain stable hemodynamics in the neonatal period or in early infancy. Here, we successfully implanted stents in the ductus venosus (DV) in 2 neonates with asplenia syndrome complicated by infracardiac type TAPVC. The first patient was a 3-day-old male neonate with severe cyanosis. Immediately after TAPVC was diagnosed, we implanted a stent in the DV. The second patient was a 0-day-old female neonate. She was diagnosed as TAPVC by fetal echocardiogram. After the scheduled delivery, a stent was successfully implanted. We believe that stent implantation in the DV in the neonatal period is effective and less invasive than surgery in patients with infracardiac type TAPVC

Fibrosarcomatous variant of dermatofibrosarcoma protuberans on the right cheek: A case report

A 52-year-old man presented with a subcutaneous mass on his right cheek. The tumor was resected. Histopathological examination of the resected tissue revealed fibrosarcomatous deromatofibrosarcoma protuberans (FS-DFSP). Since the resection resulted in a large skin defect, his cheek was reconstructed using a deep inferior epigastric artery perforator flap (DIEP). As the pathological findings showed positivity for tumor cells at the excised end, radiation therapy was applied to his right cheek. FS-DFSPs are found in about 10% of all DFSP cases, and are more malignant than other types of DFSP. Because there is a risk of local recurrence or distant metastasis, the patient should undergo close, long-term observation

Subendocardial contractile impairment in chronic ischemic myocardium: assessment by strain analysis of 3T tagged CMR

<p>Abstract</p> <p>Background</p> <p>The purpose of this study was to quantify myocardial strain on the subendocardial and epicardial layers of the left ventricle (LV) using tagged cardiovascular magnetic resonance (CMR) and to investigate the transmural degree of contractile impairment in the chronic ischemic myocardium.</p> <p>Methods</p> <p>3T tagged CMR was performed at rest in 12 patients with severe coronary artery disease who had been scheduled for coronary artery bypass grafting. Circumferential strain (C-strain) at end-systole on subendocardial and epicardial layers was measured using the short-axis tagged images of the LV and available software (Intag; Osirix). The myocardial segment was divided into stenotic and non-stenotic segments by invasive coronary angiography, and ischemic and non-ischemic segments by stress myocardial perfusion scintigraphy. The difference in C-strain between the two groups was analyzed using the Mann-Whitney U-test. The diagnostic capability of C-strain was analyzed using receiver operating characteristics analysis.</p> <p>Results</p> <p>The absolute subendocardial C-strain was significantly lower for stenotic (-7.5 ± 12.6%) than non-stenotic segment (-18.8 ± 10.2%, p < 0.0001). There was no difference in epicardial C-strain between the two groups. Use of cutoff thresholds for subendocardial C-strain differentiated stenotic segments from non-stenotic segments with a sensitivity of 77%, a specificity of 70%, and areas under the curve (AUC) of 0.76. The absolute subendocardial C-strain was significantly lower for ischemic (-6.7 ± 13.1%) than non-ischemic segments (-21.6 ± 7.0%, p < 0.0001). The absolute epicardial C-strain was also significantly lower for ischemic (-5.1 ± 7.8%) than non-ischemic segments (-9.6 ± 9.1%, p < 0.05). Use of cutoff thresholds for subendocardial C-strain differentiated ischemic segments from non-ischemic segments with sensitivities of 86%, specificities of 84%, and AUC of 0.86.</p> <p>Conclusions</p> <p>Analysis of tagged CMR can non-invasively demonstrate predominant impairment of subendocardial strain in the chronic ischemic myocardium at rest.</p

Down-Sizing in Galaxy Formation at z~1 in the Subaru/XMM-Newton Deep Survey (SXDS)

We use the deep wide-field optical imaging data of the Subaru/XMM-Newton Deep Survey (SXDS) to discuss the luminosity (mass) dependent galaxy colours down to z'=25.0 (5 x 10^9 h_{70}^{-2} Msun) for z~1 galaxies in colour-selected high density regions. We find an apparent absence of galaxies on the red colour-magnitude sequence below z'~24.2, corresponding to ~M*+2 (~10^{10} Msun) with respect to passively evolving galaxies at z~1. Galaxies brighter than M*-0.5 (8 x 10^{10} Msun), however, are predominantly red passively evolving systems, with few blue star forming galaxies at these magnitudes. This apparent age gradient, where massive galaxies are dominated by old stellar populations while less massive galaxies have more extended star formation histories, supports the `down-sizing' idea where the mass of galaxies hosting star formation decreases as the Universe ages. Combined with the lack of evolution in the shape of the stellar mass function for massive galaxies since at least z~1, it appears that galaxy formation processes (both star formation and mass assembly) should have occurred in an accelerated way in massive systems in high density regions, while these processes should have been slower in smaller systems. This result provides an interesting challenge for modern CDM-based galaxy formation theories which predict later formation epochs of massive systems, commonly referred to as ``bottom-up''.Comment: proof corrected version (MNRAS in press), 10 pages, 12 figures (of which 3 are in jpg format

Sulfide Catabolism Ameliorates Hypoxic Brain Injury

The mammalian brain is highly vulnerable to oxygen deprivation, yet the mechanism underlying the brain’s sensitivity to hypoxia is incompletely understood. Hypoxia induces accumulation of hydrogen sulfide, a gas that inhibits mitochondrial respiration. Here, we show that, in mice, rats, and naturally hypoxia-tolerant ground squirrels, the sensitivity of the brain to hypoxia is inversely related to the levels of sulfide:quinone oxidoreductase (SQOR) and the capacity to catabolize sulfide. Silencing SQOR increased the sensitivity of the brain to hypoxia, whereas neuron-specific SQOR expression prevented hypoxia-induced sulfide accumulation, bioenergetic failure, and ischemic brain injury. Excluding SQOR from mitochondria increased sensitivity to hypoxia not only in the brain but also in heart and liver. Pharmacological scavenging of sulfide maintained mitochondrial respiration in hypoxic neurons and made mice resistant to hypoxia. These results illuminate the critical role of sulfide catabolism in energy homeostasis during hypoxia and identify a therapeutic target for ischemic brain injury