Neutrino lines from MeV dark matter annihilation and decay in JUNO

We discuss the discovery potential of JUNO experiment for neutrino lines from MeV dark matter (DM) annihilation and decay in a model independent way. We find that JUNO will be able to give severe constraints on the cross section of DM annihilating into neutrinos and on the lifetime of DM decaying into neutrinos. More concretely, with $20$ years of data-taking in the fiducial volume $17$ kton, the cross section will be constrained smaller than $4\times 10^{-26}\,{\rm cm^{3}\,sec^{-1}}$ for the mass of a DM particle $15\,{\rm MeV} \lesssim m_{\chi} \lesssim 50\,{\rm MeV}$ at $90\,\%$ C.L., which might be strong enough to test thermal production mechanism of DM particles for such range of DM mass. The lifetime will be constrained as strong as $1\times 10^{24}\,{\rm sec}$ for the mass of a DM particle $m_{\chi} \simeq 100\,{\rm MeV}$ at $90\,\%$ C.L..Comment: v2: 26 pages,10 figures, added profile dependence, subdominant neutrino interactions, and references as well as made some correction

ヒト免疫細胞を用いた選択的スプライシングQTL解析によるGWAS候補領域の解析

学位の種別: 課程博士審査委員会委員 : （主査）東京大学教授 徳永 勝士, 東京大学特任准教授 神田 浩子, 東京大学教授 長瀬 隆英, 東京大学講師 槙田 紀子, 東京大学教授 田中 栄University of Tokyo(東京大学

Development of HANABI, an ultrasonication-forced amyloid fibril inducer

Goto Y., Nakajima K., Yamaguchi K., et al. Development of HANABI, an ultrasonication-forced amyloid fibril inducer. Neurochemistry International 153, 105270 (2022); https://doi.org/10.1016/j.neuint.2021.105270.Amyloid fibrils involved in amyloidoses are crystal-like aggregates, which are formed by breaking supersaturation of denatured proteins. Ultrasonication is an efficient method of agitation for breaking supersaturation and thus inducing amyloid fibrils. By combining an ultrasonicator and a microplate reader, we developed the HANABI (HANdai Amyloid Burst Inducer) system that enables high-throughput analysis of amyloid fibril formation. Among high-throughput approaches of amyloid fibril assays, the HANABI system has advantages in accelerating and detecting spontaneous amyloid fibril formation. HANABI is also powerful for amplifying a tiny amount of preformed amyloid fibrils by seeding. Thus, HANABI will contribute to creating therapeutic strategies against amyloidoses by identifying their biomarkers

Half-Time Heat Map Reveals Ultrasonic Effects on Morphology and Kinetics of Amyloidogenic Aggregation Reaction

Nakajima K., Toda H., Yamaguchi K., et al. Half-Time Heat Map Reveals Ultrasonic Effects on Morphology and Kinetics of Amyloidogenic Aggregation Reaction. ACS Chemical Neuroscience 12, 3456 (2021); https://doi.org/10.1021/acschemneuro.1c00461.Ultrasonication has been recently adopted in amyloid-fibril assays because of its ability to accelerate fibril formation, being promising in the early stage diagnosis of amyloidoses in clinical applications. Although applications of this technique are expanding in the field of protein science, its effects on the aggregation reactions of amyloidogenic proteins are poorly understood. In this study, we comprehensively investigated the morphology and structure of resultant aggregates, kinetics of fibril formation, and seed-detection sensitivity under ultrasonication using β2-microglobulin and compared these characteristics under shaking, which has been traditionally adopted in amyloid-fibril assays. To discuss the ultrasonic effects on the amyloid-fibril formation, we propose the half-time heat map, which describes the phase diagram of the aggregation reaction of amyloidogenic proteins. The experimental results show that ultrasonication greatly promotes fibril formation, especially in dilute monomer solutions, induces short-dispersed fibrils, and is capable of detecting ultra-trace-concentration seeds with a detection limit of 10 fM. Furthermore, we indicate that ultrasonication highly alters the energy landscape of an aggregation reaction due to the effect of ultrasonic cavitation. These insights contribute not only to our understanding of the effects of agitation on amyloidogenic aggregation reactions but also to their effective application in the clinical diagnosis of amyloidoses

Energy Efficiency Road Mapping in Three Future Scenarios for Lao PDR

Climate change, pollution, and energy insecurity are among the greatest problems of our time. These problems are no longer issues in particular countries but international issues. Several framework conventions on these issues are now in place throughout the world, and developing countries are no exception. Energy efficiency is one of the important issues for developing countries. Lao PDR is one such country. This paper proposes a technology roadmap and policy recommendations for Lao PDR with consideration given to a wide range of economic and social impacts of prospective technologies. For the implementation of technology assessment in the formulation of an energy efficiency roadmap, we first elaborate the social and economic conditions of Lao PDR through preliminary research and field research, and then design three scenarios for a future Lao PDR. These three scenarios are as follows: 1. The "Poverty Reduction” scenario is for electrification rate improvement; 2. The “Industrial Creation” scenario is for stable domestic energy supply; and 3. The “GMS Integration” scenario is for the acquisition of foreign exchange by energy export

Ultrastiff Amyloid-Fibril Network of α-Synuclein Formed by Surface Seeding Reaction Confirmed by Multichannel Electrodeless Quartz-Crystal-Microbalance Biosensor

Zhou L., Hajiri T., Nakajima K., et al. Ultrastiff Amyloid-Fibril Network of α-Synuclein Formed by Surface Seeding Reaction Confirmed by Multichannel Electrodeless Quartz-Crystal-Microbalance Biosensor. ACS Sensors 8, 2598 (2023); https://doi.org/10.1021/acssensors.3c00331.We developed a multichannel wireless quartz-crystal-microbalance (QCM) biosensor for mechanically studying the on-surface aggregation reaction of α-synuclein (α-syn). We find a quite unusual change in the resonant frequency that eventually exceeds the baseline, which has never been observed during seeding aggregation reaction. By incorporating a growth-to-percolation theory for fibril elongation reaction, we have favorably reproduced this unusual response and found that it can be explained only with formation of an ultrastiff fibril network. We also find that the stiffness of the fibril network grown from artificially prepared twist-type seeds is significantly higher than that from rod-type seeds. Furthermore, the stiffnesses of fibril networks grown from seeds derived from brain tissues of Parkinson’s disease (PD) and multiple system atrophy (MSA) patients show a very similar trend to those of rod and twist seeds, respectively, indicating that fibrils from MSA patients are stiffer than those from PD