42 research outputs found
Fragment shapes in impact experiments ranging from cratering to catastrophic disruption
Laboratory impact experiments have found that impact fragments tend to be elongated. Their shapes, as defined by axes a, b and c, these being the maximum dimensions of the fragment in three mutually orthogonal planes (a≥ b≥ c), are distributed around mean values of the axial ratios b/. a~. 0.7 and c/. a~. 0.5. This corresponds to a:. b:. c in the simple proportion 2:2:1 The shape distributions of some boulders on Asteroid Eros, the small- and fast-rotating asteroids (diameter <200. m and rotation period <1 h), and asteroids in young families, are similar to those of laboratory fragments created in catastrophic disruptions. Catastrophic disruption is, however, a process that is different from impact cratering. In order to systematically investigate the shapes of fragments in the range from impact cratering to catastrophic disruption, impact experiments for basalt targets 5-15. cm in size were performed. A total of 28 impact experiments were carried out by firing a spherical nylon projectile (diameter 7.14. mm) perpendicularly into the target surface at velocities of 1.60-7.13. km/s. More than 12,700 fragments with b≥ 4 mm generated in the impact experiments were measured. We found that the mean value of c/ a in each impact decreases with decreasing impact energy per unit target mass. For instance, the mean value of c/ a in an impact cratering event is nearly 0.2, which is considerably smaller than c/ a in a catastrophic disruption (~0.5). The data presented here can provide important evidence to interpret the shapes of asteroids and boulders on asteroid surfaces, and can constrain current interpretations of asteroid formation. As an example, by applying our experimental results to the boulder shapes on Asteroid Itokawa's surface, we can infer that Itokawa's parent body must have experienced a catastrophic disruption. © 2015 The Authors
Disorder-Enhanced Dimensionless Thermoelectric Figure of Merit zT of Non-stoichiometric Organic Conductor (TTT)2I3+δ (δ ≤ 0.1)
Sample dependence of dimensionless thermoelectric figure of merit (zT) and power factor (PF) were determined for the non-stoichiometric organic conductor (TTT)2I3+δ (TTT = tetrathiatetracene, δ ≤ 0.1) with the simultaneous measurement of the electrical resistivity (ρ), thermopower (S) and thermal conductivity on small single crystals. Both the zT and PF show large sample dependence between 10 and 310 K, even though all the samples have nearly stoichiometric composition of TTT : I3- ~ 2 : 1 (δ ∼ 0). It was found that both the electrical conductivity (σ = 1/ρ) and S increase at room temperature as disorder — that is phase mismatch among the iodine chains — becomes more pronounced. This behavior contrasts the usual tendency that the S decreases as the σ increases in conventional conductors; and suggests a new strategy to improve the zT and PF by introducing an appropriate type of disorder
Tsunami run-up heights of the 2003 Tokachi-oki earthquake
Tsunami height survey was conducted immediately after the 2003 Tokachi-oki earthquake. Results of the survey show that the largest tsunami height was 4 m to the east of Cape Erimo, around Bansei-onsen, and locally at Mabiro. The results also show that the tsunami height distribution of the 2003 Tokachi-oki earthquake is clearly different from that of the 1952 Tokachi-oki earthquake, suggesting the different source areas of the 1952 and 2003 Tokachioki earthquakes. Numerical simulation of tsunami is carried out using the slip distribution estimated by Yamanaka and Kikuchi (2003). The overall pattern of the observed tsunami height distribution along the coast is explained by the computed ones although the observed tsunami heights are slightly smaller. Large later phase observed at the tide gauge in Urakawa is the edge wave propagating from Cape Erimo along the west coast of the Hidaka area.The 2003 Tokachi-oki earthquak
The whole blood transcriptional regulation landscape in 465 COVID-19 infected samples from Japan COVID-19 Task Force
「コロナ制圧タスクフォース」COVID-19患者由来の血液細胞における遺伝子発現の網羅的解析 --重症度に応じた遺伝子発現の変化には、ヒトゲノム配列の個人差が影響する--. 京都大学プレスリリース. 2022-08-23.Coronavirus disease 2019 (COVID-19) is a recently-emerged infectious disease that has caused millions of deaths, where comprehensive understanding of disease mechanisms is still unestablished. In particular, studies of gene expression dynamics and regulation landscape in COVID-19 infected individuals are limited. Here, we report on a thorough analysis of whole blood RNA-seq data from 465 genotyped samples from the Japan COVID-19 Task Force, including 359 severe and 106 non-severe COVID-19 cases. We discover 1169 putative causal expression quantitative trait loci (eQTLs) including 34 possible colocalizations with biobank fine-mapping results of hematopoietic traits in a Japanese population, 1549 putative causal splice QTLs (sQTLs; e.g. two independent sQTLs at TOR1AIP1), as well as biologically interpretable trans-eQTL examples (e.g., REST and STING1), all fine-mapped at single variant resolution. We perform differential gene expression analysis to elucidate 198 genes with increased expression in severe COVID-19 cases and enriched for innate immune-related functions. Finally, we evaluate the limited but non-zero effect of COVID-19 phenotype on eQTL discovery, and highlight the presence of COVID-19 severity-interaction eQTLs (ieQTLs; e.g., CLEC4C and MYBL2). Our study provides a comprehensive catalog of whole blood regulatory variants in Japanese, as well as a reference for transcriptional landscapes in response to COVID-19 infection
DOCK2 is involved in the host genetics and biology of severe COVID-19
「コロナ制圧タスクフォース」COVID-19疾患感受性遺伝子DOCK2の重症化機序を解明 --アジア最大のバイオレポジトリーでCOVID-19の治療標的を発見--. 京都大学プレスリリース. 2022-08-10.Identifying the host genetic factors underlying severe COVID-19 is an emerging challenge. Here we conducted a genome-wide association study (GWAS) involving 2, 393 cases of COVID-19 in a cohort of Japanese individuals collected during the initial waves of the pandemic, with 3, 289 unaffected controls. We identified a variant on chromosome 5 at 5q35 (rs60200309-A), close to the dedicator of cytokinesis 2 gene (DOCK2), which was associated with severe COVID-19 in patients less than 65 years of age. This risk allele was prevalent in East Asian individuals but rare in Europeans, highlighting the value of genome-wide association studies in non-European populations. RNA-sequencing analysis of 473 bulk peripheral blood samples identified decreased expression of DOCK2 associated with the risk allele in these younger patients. DOCK2 expression was suppressed in patients with severe cases of COVID-19. Single-cell RNA-sequencing analysis (n = 61 individuals) identified cell-type-specific downregulation of DOCK2 and a COVID-19-specific decreasing effect of the risk allele on DOCK2 expression in non-classical monocytes. Immunohistochemistry of lung specimens from patients with severe COVID-19 pneumonia showed suppressed DOCK2 expression. Moreover, inhibition of DOCK2 function with CPYPP increased the severity of pneumonia in a Syrian hamster model of SARS-CoV-2 infection, characterized by weight loss, lung oedema, enhanced viral loads, impaired macrophage recruitment and dysregulated type I interferon responses. We conclude that DOCK2 has an important role in the host immune response to SARS-CoV-2 infection and the development of severe COVID-19, and could be further explored as a potential biomarker and/or therapeutic target
Effects of intermediate annealing and cold rolling reduction on texture evolution in an Al–Mg–Si alloy*
Establishment of a Bacterial Expression System and Immunoassay Platform for the Major Capsid Protein of HcRNAV, a Dinoflagellate-Infecting RNA Virus
A case of pulmonary metastasis from poorly differentiated thyroid carcinoma 43 years after thyroidectomy
A case of marked rectal stenosis due to Douglas’ pouch metastasis of renal pelvic carcinoma successfully treated with salvage enfortumab vedotin: correlation between serum KL‐6 levels and tumor response
Introduction We report a rare case of marked rectal stenosis due to Douglas' pouch metastasis of renal pelvic urothelial carcinoma successfully treated with enfortumab vedotin. Case presentation A 77‐year‐old female presented with difficulty in defecation and abdominal distension. She had received two courses of cisplatin plus gemcitabine followed by four courses of maintenance avelumab for postoperative lymph node metastasis of renal pelvic urothelial carcinoma. KL‐6 levels were elevated, and a computed tomography scan revealed an irregularly shaped large mass occupying Douglas' pouch, with marked rectal stenosis. Metastatic urothelial carcinoma was pathologically diagnosed, and enfortumab vedotin was initiated after colostomy. After 12 courses of enfortumab vedotin, metastatic lesions showed marked shrinkage and KL‐6 levels decreased. Conclusion Enfortumab vedotin elicited a remarkable response in treating rectal stenosis due to metastasis of renal pelvic urothelial carcinoma in Douglas' pouch. Furthermore, serum KL‐6 levels were correlated with the severity of metastatic urothelial carcinoma
Response to Immune Checkpoint Inhibitor Therapy in Patients with Unresectable Recurrent Malignant Pleural Mesothelioma Shown by FDG-PET and CT
Background: To compare three FDG-PET criteria (EORTC, PERCIST, imPERCIST) with CT criteria (combined modified RECIST and RECIST 1.1) for response evaluation and prognosis prediction in patients with recurrent MPM treated with ICI monotherapy. Methods: Thirty MPM patients underwent FDG-PET/CT and contrast-enhanced CT at the baseline and during nivolumab therapy (median 10 cycles). Therapeutic response was evaluated according to EORTC, PERCIST, imPERCIST, and CT criteria. PFS and OS were examined using log-rank and Cox methods. Results: CMR/PMR/SMD/PMD numbered 5/3/4/18 for EORTC, 5/1/7/17 for PERCIST, and 5/3/9/13 for imPERCIST. With CT, CR/PR/SD/PD numbered 0/6/10/14. There was high concordance between EORTC and PERCIST (κ = 0.911), and PERCIST and imPERCIST (κ = 0.826), while that between EORTC and imPERCIST (κ = 0.746) was substantial, and between CT and the three PET criteria moderate (κ = 0.516–0.544). After median 14.9 months, 26 patients showed progression and nine died. According to both PET and CT findings, patients with no progression (CMR/PMR/SMD or CR/PR/SD) showed significantly longer PFS and somewhat longer OS than PMD and PD patients (EORTC p = 0.0004 and p = 0.055, respectively; PERCIST p = 0.0003 and p = 0.052; imPERCIST p p = 0.089; CT criteria p = 0.0015 and p = 0.056). Conclusions: Both FDG-PET and CT criteria are accurate for response evaluation of ICI therapy and prediction of MPM prognosis. In comparison with CT, all three FDG-PET/CT criteria judged a greater percentage of patients (16.7%) as CMR, while two (EORTC, PERCIST) judged a greater percentage (10–13.3%) as PMD. For predicting PFS, the three FDG-PET criteria were superior to the CT criteria, and imPERCIST demonstrated the highest rate of accurate prediction