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Functional Heterogeneity within the Primate Ventral Striatum for Motivational Regulation
No full textThe ventral striatum (VS) is a key brain region for reward processing and motivation, and its dysfunctions have been implicated in psychiatric disorders such as apathy and obsessive-compulsive disorder. Although functional heterogeneity within the VS has been well established in rodents, its relevance and mechanisms in primates remain unclear. To address this issue, we performed bilateral pharmacological inactivation of the VS in two male macaque monkeys using muscimol, a GABAA receptor agonist. Precise targeting was achieved through computed tomography and magnetic resonance imaging. Behavioral effects were evaluated using two methods: a goal-directed task with variable rewards and analysis of spontaneous behavior. Our results demonstrated that anterior (a)VS inactivation induced a hypoactivity state that we termed "resting," whereas posterior (p)VS inactivation elicited compulsive-like "checking" behaviors. Notably, neither the aVS nor the pVS inactivation affected reward value or drive processing, thus differentiating aVS and pVS from those involved in incentive motivation, such as the rostromedial caudate and ventral pallidum. Retrograde tracing demonstrated distinct anatomical projection patterns for the aVS and pVS, supporting their functional segregation. Together, the present results suggest the functional heterogeneity of the primate VS along its anterior-posterior axis, with the aVS and pVS participating in distinct motivational control circuits. Our findings may have important implications for understanding the neural mechanisms of psychiatric disorders and for the development of new therapeutic approaches.Significance Statement The ventral striatum (VS) is a core brain region that is involved in motivation and reward-based behaviors. Its dysfunction is implicated in psychiatric disorders such as apathy and obsessive-compulsive disorder. In macaque monkeys, we used imaging-guided pharmacological manipulations to reveal that the anterior and posterior VS subregions have distinct roles in motivation, independent of the incentive or reward drive. Specifically, anterior VS inactivation induced a hypoactive state, whereas posterior VS inactivation elicited compulsive-like behaviors. These findings reveal distinct motivational mechanisms within the primate VS, thus offering valuable insights into the neural basis of psychiatric disorders and identifying promising therapeutic targets.journal articl
Deuterium retention properties and bubble behaviors of Be12Ti after irradiation with D+ at high temperature
No full textIn the Japanese demonstration (JA DEMO) fusion reactor, Be12Ti blocks as a neutron multiplying material and Li2TiO3 pebbles as a breeding material will be planned to set in the blanket. When the replacement of the blanket due to the life of the structure materials, tritium generation with 200 appm T in Be12Ti blocks can be anticipated. The Be12Ti blocks containing tritium may cause several problematic issues in JA DEMO. The objective of this study aimed to evaluate the correlation between deuterium (D) retention properties and the bubble behaviors in Be12Ti.
We investigated the D retention properties in the Be12Ti samples, which were irradiated with D+ ions at R.T.-873 K using thermal desorption spectroscopy. The bubble behaviors in the thin Be12Ti samples were observed under annealing using in-situ transmission electron microscope (TEM). And the Be samples were prepared to be comparable with Be12Ti and done similarly to the same experiment.
The D desorption peaks were confirmed from the mechanical-polished and electropolished Be12Ti samples after irradiation with D+ at R.T. and high temperature. For both mechanical-polished and electropolished Be12Ti samples, the desorption peak shifted to higher temperatures with increasing irradiation temperatures. In-situ TEM observed the bubble behaviors, and Most of the bubbles wouldn’t change in thin Be12Ti samples after irradiation with D+ at R.T. and 673 K during annealing (~1073 K). These results indicate that no correlation between the deuterium releases and the bubble behavior in Be12Ti until 1073 K.journal articl
Accessing a Hidden Pathway to Supramolecular Toroid through Vibrational Strong Coupling
No full textControl over specific intermolecular interactions is crucial to the formation of unique supramolecular assemblies. Recently, vibrational strong coupling (VSC) has emerged as a new tool for manipulating these interactions. Although VSC shows promise for controlling molecular assembly, it has not yet demonstrated the capability to open a pathway for creating structures that are inaccessible by conventional assembly methods. Here, we used VSC to control the transformation process of a naphthalenediimide supramolecular polymer induced by a click reaction. The supramolecular polymers with reactive ethynyl groups undergo a transformation from long fibers to thick fibers upon induction by an amino-yne click reaction in the absence of VSC. Under VSC of the C?H stretch, the click reaction within supramolecular polymers is accelerated; no such acceleration occurs in the reaction of individual monomers, suggesting that the acceleration is due to changes in the assembled structures. Indeed, applying the VSC to the C?H stretch uniquely altered the morphological transformation process, leading to the formation of metastable toroids instead of thick fibers. Notably, the molecular assembly cannot be directed toward a toroidal structure without a VSC. Theoretical simulations suggested that slipped packing configurations in the supramolecular polymers form the curvature necessary for toroidal structures. The experimental results, supported by theoretical simulations, suggest that intermolecular interactions among naphthalenediimide molecules are modified under VSC, leading to a slipped packing configuration of the toroidal assembly. These findings link the VSC-induced modulation of intermolecular interactions to structural outcomes, establishing VSC as a tool for manipulating molecular assembly beyond traditional assembly methods.journal articl
Irradiation Defects in F82H Steel: Insights from TEM/STEM/EF-TEM
No full textIn F82H steel, a promising structural material for fusion reactors, the accelerating deterioration in mechanical properties is of significant concern due to the accumulation of He by 14-MeV neutron irradiation. The aim of the present study is to elucidate the morphology of He bubbles in F82H steel by employing microscopic analysis. The experimental approach entailed the irradiation of single- and dual-ion beams up to 80 dpa at 703 K subsequently, a comprehensive analysis using TEM/STEM/EF-TEM was performed to study the irradiation defects, including dislocation loops and helium bubbles. A STEM analysis revealed a dislocation loop density of 2-5 x1021 m-3, and the He led to a decrease in size of loop. For the He bubble evaluation, TEM mode encountered difficulties in discerning bubbles smaller than 2 nm, while the contrast is insufficient for the detection of fine bubbles in the STEM mode. Conversely, EF-TEM mode, exhibiting sensitivity to material density fluctuations, detected ~1 nm bubbles with high signal-to-noise ratio. The density of the bubble was estimated to be 6-7 x 1022 m?3, exhibiting a modest increase with increasing dose. The presence of minor peaks at approximately 7 and 18 nm at 20 dpa diminished at higher doses, reducing the multimodal distribution. It has been demonstrated that coarse bubbles persist but decrease in density, which poses a concern for material integrity due to the presence of coarse bubbles under high-dose conditions.journal articl
Ultrahigh Resolution and High Efficiency RIXS/XES Spectrometers at NanoTerasu BL02U and BL07U
No full textNanoTerasuに設置された軟X線RIXS/XES分光器2台[BL02U(2D-RIXS), BL07U(HORNET-II)]の設計と初期性能を報告する。2D-RIXSは独自設計で超高分解能(E/ΔE>5万)を達成。HORNET-IIは高効率と多様な試料環境対応に強みを持ち、両者の相補利用による先端科学研究の展開が期待される。journal articl
Minimally invasive, wide-field two-photon imaging of the brainstem at cellular resolution
No full textThe nucleus tractus solitarii (NTS), a brainstem structure, is proposed as a critical gateway for regulating emotions through brain-viscera communication and for therapies based on vagus nerve stimulation (VNS). However, how the NTS processes signals from various organs remains unclear. Investigating this has been challenging due to the NTS’s deep location beneath the cerebellum and its being surrounded by brainstem regions critical to vital functions, which makes direct observation difficult. To address this issue, we developed an in vivo two-photon imaging method using a double-prism-based optical interface, allowing minimally invasive observation while keeping the surrounding regions mostly intact.journal articl
Enhancing Near-Infrared Photoluminescence of Ag8GeS6 Quantum Dots Through Compositional Fine-Tuning and ZnS Coating for In Vivo Bioimaging
No full textQuantum dots (QDs) composed of a group I?IV?VI semiconductor, Ag8GeS6, have been intensively investigated for constructing efficient energy conversion systems. However, their potential for photoluminescence (PL)-based applications has remained unexplored. Herein, the first successful preparation of Ag8GeS6 QDs exhibiting near-infrared (NIR) PL is reported. These Ag8GeS6 QDs with an average diameter of 4.2?4.6 nm has an almost constant energy gap at 1.48?1.45 eV, even when the Ge/(Ag+Ge) precursor ratio is varied from 0.05 to 0.90. A significant PL peak is observed at 920 nm, the intensity being enlarged with an increase in the Ge/(Ag+Ge) ratio. The use of Ag8GeS6 QDs prepared with Ge/(Ag+Ge) = 0.82 in the precursors result in a PL quantum yield (QY) of 11%, which is further enhanced to 40% through surface coating with a ZnS shell of 1.0 nm in thickness, with the PL peak wavelength being slightly blue-shifted to 900 nm. Following surface modification with 3-mercaptopropionic acid for homogeneous dispersion in aqueous solutions, the Ag8GeS6@ZnS QDs are utilized as an NIR PL probe for in vivo bioimaging. PL signals are clearly detected from depths of at least 15 mm beneath the back skin of a mouse, demonstrating their deep-tissue imaging capability.journal articl
Extended single-dose toxicity study of [At]meta-astatobenzylguanidine in normal mice in preparation for the first-in-human clinical trial of targeted alpha therapy for pheochromocytoma and paraganglioma.
No full textTargeted alpha-particle therapy (TAT) is promising with a greater therapeutic effect than conventional beta radionuclide therapy. To develop human clinical trials of [At]meta-astatobenzylguanidine ([At]MABG), we have conducted an extended single-dose toxicity study of [At]MABG in normal mice in consultation with the Pharmaceuticals and Medical Devices Agency (PMDA). We are currently working for human clinical trials of [At]MABG. After consultation with the Pharmaceuticals and Medical Devices Agency, we conducted a single-dose toxicity study of [At]MABG in normal mice in preparation for a human clinical trial of [At]MABG.journal articl
RESULTS OF ELECTRON CYCLOTRON HEATING AND CURRENT DRIVE SYSTEM OPERATION IN THE INTEGRATED COMMISSIONING PHASE ON JT-60SA
No full textJT-60SAの統合コミッショニングでは2系統のECH/CD装置を運用し、ほとんどすべてのプラズマ実験シーケンスで入射を行った。運転に際し、従来長距離伝送の成立性に懸念があった大口径導波管伝送路の伝送効率測定を実施し、敷設精度を定量的に明らかにした。また、真空容器へのミリ波入射によって1MW/1sの入射が可能となるようコンディショニングを行った。コンディショニングの結果、プラズマ実験での入射成功率は平均90%となり、高い信頼性を実証した。これらの運転成果を元に、加熱実験フェーズのために新たに敷設される4系統の伝送系の設計評価を実施し、4系統3周波数すべてで設計目標値を上回る85%以上の伝送効率を得られる見込みを得た。QSTフュージョンエネルギーワークショップconference presentatio
Automated design rationalization of robot componentconfiguration for in-vessel task of ITER Blanket Remote Handling System
No full text本論文では、ITERにおけるブランケット遠隔保守システム(Blanke Remote Handling System, BRHS)のために開発した、ロボットの機器設計合理化手法と、同手法によって実際にBRHS機器の設計を合理化した結果について発表する。核融合炉の遠隔保守ロボットは、大重量物のハンドリングと、狭隘な空間で動作を成立させるための小型化の両立が求められており、そのような制約を満たす機器設計や設計合理化に対しては、複数の設計案で動作成立性評価を試行することが有効な手段の1つである。しかしながら、オペレータがCADソフトウェアを用いて手作業で形状モデルを作成し、運動学モデルの構成と動作成立性評価を行うという従来手法は、作業に労力と時間を要するものであった。このため、半ばエンジニアリングジャッジメント的に定めた限られた数の設計案でしか動作成立性評価を試行できず、設計の合理性が不十分な設計解、例えば機器サイズが過度に保守的で大型になってしまうような設計解しか得られないことが課題であった。本研究では、ロボット機器の形状モデル及び運動学モデルの変更と、バーチャル・リアリティー(Virtual Reality, VR)上での動作成立性評価を自動化した。これにより、設計効率を向上し、さらに様々な形状に対する動作成立性評価の試行が可能になったことで、機器の設計合理性自体も向上した。実際に開発手法を、BRHS機器の一種である遮蔽ブロックグリッパに適用した結果、狭隘な空間での動作成立性を確保しつつ、従来設計と比べて約15%小型化した設計解を得ることに成功した。QSTフュージョンエネルギーワークショップconference presentatio