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情報量に偏りや欠損がある時系列データを用いた機械学習時間発展モデリング (スーパーコンピュータ共同研究制度 (若手・女性研究者奨励枠) 研究報告)
No full text本稿は斉木吉隆氏 (一橋大学経営管理研究科) との共同研究に基づくものである
Purple LED light and crude glycerol synergistically enhance astaxanthin production in Aurantiochytrium limacinum
No full textAurantiochytrium limacinum is a heterotrophic marine protist known for its ability to co-produce docosahexaenoic acid (DHA) and carotenoids such as astaxanthin. Despite its biotechnological potential, industrial application is hindered by high production costs. In this study, we investigated the effects of different light wavelengths and carbon sources on the production of carotenoids and neutral lipids in A. limacinum. Purple LED light (410-420 nm) significantly enhanced the biosynthesis of β-carotene, canthaxanthin, and astaxanthin compared to white light or darkness. Additionally, the use of glycerol or crude glycerol, a byproduct of biodiesel production, affected carotenoid profiles. β-Carotene and canthaxanthin were more abundant in cultures supplemented with glycerol or crude glycerol, whereas astaxanthin was predominantly produced in cultures supplemented with glucose. Notably, crude glycerol treated via acidification and activated carbon enabled cell growth and metabolite production comparable to that observed with glucose. These findings suggest that light quality and carbon source synergistically influence carotenoid biosynthesis in A. limacinum. The use of industrial byproducts combined with light optimization represents a sustainable and cost-effective strategy for enhancing microbial production of high-value compounds
Markovnikov-Selective Hydroboration of Unactivated Alkenes via MHAT under Cobalt/Photoredox Dual Catalysis
No full textCatalytic Markovnikov-selective hydroboration of unactivated alkenes is a powerful tool for accessing alkyl boronic esters. Here, we report Markovnikov-selective MHAT hydroboration of unactivated alkenes enabled by cobalt/photoredox dual catalysis. The reaction proceeded via radical intermediates, providing high regioselectivity with mono-, di-, and trisubstituted alkenes
Collapse of Rotating Very Massive Stellar Cores Leading to a Black Hole and a Massive Disk as a Source of Gravitational Waves
No full textWe derive models of rotating very massive stellar cores with mass ≈10²-10⁴ ⊙ that are marginally stable to the pair-unstable collapse, assuming that the core is isentropic and composed primarily of oxygen. It is shown that cores with mass ≲10³ ⊙ can form a massive disk with the mass more than 10% of the core mass around the formed black hole if the core is rotating with more than 30% of the Keplerian limit. We also indicate that the formation of rapidly spinning massive black holes such as the black holes of GW231123 naturally accompanies massive disk formation. By using the result of our previous study, which showed that the massive disk is unstable to the nonaxisymmetric deformation, we predict the amplitude and frequency of gravitational waves and show that the collapse of rotating very massive stellar cores can be a promising source of gravitational waves for the Einstein Telescope. The detection of such gravitational waves will provide us with important information about the formation process of intermediate mass black holes
Glutathione Synthesis via the Cystine/Glutamate Transporter Promotes the Formation of Tertiary Lymphoid Structures in the Kidney
No full text三次リンパ組織における代謝微小環境の解明 --グルタチオンが鍵となる免疫代謝制御機構--. 京都大学プレスリリース. 2025-08-21.[Background] Tertiary lymphoid structure (TLS), an ectopic lymphoid tissue induced under chronic inflammation, develops in various kidney diseases and is associated with poor prognosis. The immune system requires metabolic resources to support immune function and lymphocyte proliferation. Hence, dramatic metabolic alterations presumably occur during the formation of TLS. However, it remains unclear whether metabolic remodeling occurs during this formation and its underlying mechanism. [Methods] In a murine model of TLS in the kidney, we used imaging mass spectrometry and metabolome analysis to investigate the metabolic pathway that characterizes TLS. We also performed in situ hybridization with immunofluorescence and pharmacologic inhibition to explore the expression and function of the key molecules governing the pivotal metabolic pathway. We analyzed urine samples from mice and humans to explore the metabolites estimating the presence of TLS in the kidney. [Results] Significant glutathione accumulation and depletion of cysteine, which is essential for glutathione synthesis, was observed specifically within TLS. The kidneys with TLS exhibited higher glutathione concentrations than healthy kidneys. TLS also showed significant accumulation of 4-hydroxynonenal and 8-hydroxy-2′ -deoxyguanosine, markers of oxidative stress. Dendritic cells and fibroblasts within TLS expressed the cystine/glutamate transporter, which regulates glutathione synthesis, and supplied synthesized glutathione to lymphocytes, which lacked its expression. Pharmacologic inhibition of the cystine/glutamate transporter prevented the formation of TLS in the kidney. Furthermore, enhanced glutathione synthesis within TLS was reflected in elevated urinary glutathione concentrations in both mice and humans, which effectively detected the presence of TLS in the kidney in IgA nephropathy patients. [Conclusions] Glutathione significantly accumulated within TLS in the kidney. Inhibition of the cystine/glutamate transporter prevented the formation of TLS. Urinary glutathione served as a biomarker to detect TLS in the kidney
Real-world medical expenses of hematopoietic stem cell transplantation in Japan: a nationwide database study
No full textA Correction to this article was published on 07 January 2026
Task-invariant anterior-to-posterior large-scale phase gradients of electrocorticogram oscillations during picture naming and wrist extension
No full text皮質脳波進行波に基づく選択的情報伝搬の仕組みを発見. 京都大学プレスリリース. 2026-01-15.Electrocorticogram (ECoG) recordings during rest have shown that theta and alpha oscillations on the cortical surface form “cortical traveling waves” across large-scale brain networks, known as phase gradients. Theoretically, these large-scale phase gradients are thought to contribute to asymmetric coupling among cortical regions. During cognitive tasks, such large-scale gradients presumably support flexible information transfer between task-related cortices; however, this has not been extensively evaluated. Here, we examined the large-scale phase gradients of ECoG theta–alpha (7 Hz) oscillations during picture naming and wrist extension tasks. Notably, large-scale anterior-posterior phase gradients that spontaneously appeared from the anterior temporal lobe (ATL) to posterior regions were only weakly dependent on task type. Nonetheless, the degree of synchronization (termed “relative phase polarity”) in task-relevant regions was significantly modulated after stimulus and movement onsets. Moreover, increased local synchronization to the traveling waves was associated with enhanced phase-dependent high-gamma activity, possibly reflecting information processing within these areas. These results suggest that task-invariant anterior-to-posterior phase gradients continuously support asymmetric coupling within a widely distributed cortical network involving the ATL and other regions and that this coupling is regulated by task-relevant regions through modulation of their local synchrony with the traveling waves
Why Aggregate Indicators Fail in Fiscal Sustainability Evaluation: Tax Base Heterogeneity, Reweighting, and the Limits of GDP Elasticity
No full textFiscal sustainability is commonly evaluated using aggregate indicators such as GDP growth and tax revenue elasticity, yet this paper shows that such indicators can be fundamentally insufficient once fiscal capacity depends on the evolving structure of underlying tax bases. When tax revenue is generated by heterogeneous tax bases whose growth rates and revenue weights evolve over time, aggregation induces an intrinsic informational loss that cannot be resolved by refining elasticity estimates. To establish this result, tax revenue is modeled as the aggregation of industry-specific tax bases subject to heterogeneous growth dynamics and institutional features of corporate taxation. Within this framework, we show that tax revenue growth cannot, in general, be characterized by a single, time-invariant elasticity with respect to aggregate output. The analysis clarifies the structural conditions under which conventional benchmarks, including the Domar condition, remain valid. When tax bases evolve proportionally with aggregate output and industrial composition is stable, the Domar condition emerges as a special case of a more general stability condition. Once these restrictive assumptions are relaxed, changes in tax base composition and sectoral profit dynamics can generate systematic divergences between output growth and tax revenue growth. The paper derives a structural fiscal stability condition in which debt sustainability depends on the weighted growth dynamics of underlying tax bases rather than on aggregate output alone. Stylized facts from Japan and the United States illustrate how differences in industrial structure and tax institutions shape revenue dynamics in practice. More fundamentally, the analysis highlights the structural limitations of aggregate-indicator–based fiscal evaluation: fiscal sustainability is a property of how fiscal capacity is generated through the composition and dynamics of underlying tax bases.Appendix: [11]-[15
EGAP Writing 1: Academic Essays_2026 Edition
No full text本文ファイル登録(2026-01-08)本文ファイル差し替え(2026-02-24)To Students & Teachers [1]Introduction to Academic Writing [3]Paragraphs & Topic Sentences [6]Supporting Sentences [12]Paragraph Writing [17]Writing Process [21]Introduction Paragraph [29]Conclusion Paragraph [34]Citations & Paraphrase [39]Essay Structure [44]Essay Outline [49]Definitions, Opinions, Facts, & Format [52]Peer Review [57]Revising & Documenting [61]Proofreading & Reflecting [65]List of Appendices [67]Key Vocabulary [76