Publications by authors named "Sassa Y"

Quantum fluctuations in low-dimensional systems and near quantum phase transitions have significant influences on material properties. Yet, it is difficult to experimentally gauge the strength and importance of quantum fluctuations. Here we provide a resonant inelastic x-ray scattering study of magnon excitations in Mott insulating cuprates.

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Purpose: To explore the clinical features of COVID-19-associated conjunctivitis with the objective of preventing the spread of infection.

Study Design: Retrospective cohort study.

Methods: From March 2020 to March 2021, we retrospectively reviewed 26 (9.

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Article Synopsis
  • The study examines how the combination of spin-orbit coupling and crystal symmetry in thin materials can create unique spin-polarized bands, which could result in new physical properties.
  • Specifically, it discusses bilayer materials where breaking inversion symmetry can lead to oppositely polarized spins in different layers.
  • The research demonstrates that growing a Tl bilayer on Ag(111) with lattice mismatch reveals hidden spins and creates a new phenomenon of band splitting in both spin and space, achieved by carefully tuning the interface interaction strength.
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We present an in situ uniaxial pressure device optimized for small angle x-ray and neutron scattering experiments at low-temperatures and high magnetic fields. A stepper motor generates force, which is transmitted to the sample via a rod with an integrated transducer that continuously monitors the force. The device has been designed to generate forces up to 200 N in both compressive and tensile configurations, and a feedback control allows operating the system in a continuous-pressure mode as the temperature is changed.

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In high-temperature cuprate superconductors, stripe order refers broadly to a coupled spin and charge modulation with a commensuration of eight and four lattice units, respectively. How this stripe order evolves across optimal doping remains a controversial question. Here we present a systematic resonant inelastic x-ray scattering study of weak charge correlations in LaSrCuO and LaEuSrCuO.

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Two-dimensional (2D) triangular lattice antiferromagnets (2D-TLA) often manifest intriguing physical and technological properties, due to the strong interplay between lattice geometry and electronic properties. The recently synthesized 2-dimensional transition metal dichalcogenide LiCrTe[Formula: see text], being a 2D-TLA, enriched the range of materials which can present such properties. In this work, muon spin rotation ([Formula: see text]SR) and neutron powder diffraction (NPD) have been utilized to reveal the true magnetic nature and ground state of LiCrTe[Formula: see text].

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  • The study aimed to create and validate a new scale for measuring email addiction tendency and its effects on behavior and brain structure.
  • Researchers found that higher email addiction scores were linked to lower nonverbal reasoning abilities and higher severity of depression symptoms.
  • Additionally, the study discovered a positive correlation between email addiction tendency and increased gray matter volume in the left rostrolateral prefrontal cortex, suggesting potential impacts on mental health.
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The magnetic phase diagram of Sr[Formula: see text]Ca[Formula: see text]Co[Formula: see text]P[Formula: see text] as a function of hydrostatic pressure and temperature is investigated by means of high pressure muon spin rotation, relaxation and resonance ([Formula: see text]SR). The weak pressure dependence for the [Formula: see text] compounds suggests that the rich phase diagram of Sr[Formula: see text]Ca[Formula: see text]Co[Formula: see text]P[Formula: see text] as a function of x at ambient pressure may not solely be attributed to chemical pressure effects. The [Formula: see text] compound on the other hand reveals a high pressure dependence, where the long range magnetic order is fully suppressed at [Formula: see text] kbar, which seem to be a first order transition.

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The detrimental effects of high-level mercury exposure on the central nervous system as well as effects of low-level exposure during early development have been established. However, no previous studies have investigated the effects of mercury level on brain morphometry using advance imaging techniques in young adults. Here, utilizing hair analysis which has been advocated as a method for biological monitoring, data of regional gray matter volume (rGMV), regional white matter volume (rWMV), fractional anisotropy (FA) and mean diffusivity (MD), cognitive functions, and depression among 920 healthy young adults in Japan, we showed that greater hair mercury levels were weakly but significantly associated with diminished cognitive performance, particularly on tasks requiring rapid processing (speed measures), lower depressive tendency, lower rGMV in areas of the thalamus and hippocampus, lower rWMV in widespread areas, greater FA in bilaterally distributed white matter areas overlapping with areas of significant rWMV reductions and lower MD of the widely distributed gray and white matter areas particularly in the bilateral frontal lobe and the right basal ganglia.

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X-ray absorption and resonant inelastic x-ray scattering spectra of LaPtSisingle crystal at the Si 2and La 4edges are presented. The data are interpreted in terms of density functional theory, showing that the Si spectra can be described in terms of Siandlocal partial density of states (LPDOS), and the La spectra are due to quasi-atomic local 4excitations. Calculations show that Pt-LPDOS dominates the occupied states, and a sharp localized Lastate is found in the unoccupied states, in line with the observations.

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Background: Childhood is an extremely important time for neural development that has a critical role in human intelligence. Efficient information processing is crucial for higher intelligence, so the intra- or inter-hemispheric interaction is vital. However, the relationship between neuroanatomical connections and intelligence in typically developing children, as well as sex differences in this relationship, remains unknown.

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Static stripe order is detrimental to superconductivity. Yet, it has been proposed that transverse stripe fluctuations may enhance the inter-stripe Josephson coupling and thus promote superconductivity. Direct experimental studies of stripe dynamics, however, remain difficult.

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Shame and guilt are distinct negative moral emotions, although they are usually regarded as overlapping affective experiences. Of these two emotions, shame is more closely related to concerns about other people's judgment, whereas guilt is more related to concerns about one's own judgment. Although some studies have tried to identify the psychological process underlying shame as opposed to guilt, there is no clear evidence of brain regions that are specifically relevant to the experience of shame rather than guilt and, more generally, self-blame.

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The structural and functional brain characteristics associated with the excessive use of the internet have attracted substantial research attention in the past decade. In current study, we used voxel-based morphometry (VBM) and multiple regression analysis to assess the relationship between internet addiction tendency (IAT) score and regional gray and white matter volumes (rGMVs and rWMVs) and brain activity during a WM task in a large sample of healthy young adults (n = 1,154, mean age, 20.71 ± 1.

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Sodium transition metal oxides with a layered structure are one of the most widely studied cathode materials for Na-ion batteries. Since the mobility of Na in such cathode materials is a key factor that governs the performance of material, electrochemical and muon spin rotation and relaxation techniques are here used to reveal the Na-ion mobility in a P2-type NaMgNiMnO ( = 0, 0.02, 0.

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Article Synopsis
  • Lead exposure is toxic and particularly harmful to the central nervous system, but its specific effects on brain microstructure and function had not been thoroughly studied before this research.
  • The study analyzed data from 920 young adults, revealing that higher levels of lead in hair samples are weakly linked to changes in brain activity during memory tasks and alterations in the brain’s white matter structure.
  • Participants with increased lead levels also showed poorer performance in cognitive tests and higher impulsivity, suggesting that even low levels of lead exposure can have subtle but significant effects on brain function and behavior.
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Charge order is universal to all hole-doped cuprates. Yet, the driving interactions remain an unsolved problem. Electron-electron interaction is widely believed to be essential, whereas the role of electron-phonon interaction is unclear.

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The quantum Hall effect (QHE) is traditionally considered to be a purely two-dimensional (2D) phenomenon. Recently, however, a three-dimensional (3D) version of the QHE was reported in the Dirac semimetal ZrTe. It was proposed to arise from a magnetic-field-driven Fermi surface instability, transforming the original 3D electron system into a stack of 2D sheets.

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Although it is known that health is not merely the absence of disease, the positive aspects of mental health have been less comprehensively researched compared with its negative aspects. Subjective well-being (SWB) is one of the indicators of positive psychology, and high SWB is considered to benefit individuals in multiple ways. However, the neural mechanisms underlying individual differences in SWB remain unclear, particularly in terms of brain microstructural properties as detected by diffusion tensor imaging.

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Childhood socioeconomic status is robustly associated with various children's cognitive factors and neural mechanisms. Here we show the association of childhood socioeconomic status with psychometric intelligence and mean diffusivity and fractional anisotropy using diffusion tensor imaging at the baseline experiment (N = 285) and longitudinal changes in these metrics after 3.0 ± 0.

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  • - The study explores how AA amyloidosis, a disease involving protein aggregation, can be transmitted orally across species, noting that this transmission is less efficient between different species compared to within the same species.
  • - Researchers previously discovered that mice given large amounts of bovine AA along with inflammatory stimulation did not develop AA amyloidosis, leading to a hypothesis about low absorption rates within Peyer's patches—the lymphoid tissues in the intestines responsible for immune responses.
  • - Investigations showed minimal uptake of bovine AA by Peyer's patches and little translocation to other organs, suggesting that the inefficiency of amyloid uptake in these areas may contribute to the species-barrier preventing effective cross-species transmission of AA amyloidosis.
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The advent of nanotechnology has hurtled the discovery and development of nanostructured materials with stellar chemical and physical functionalities in a bid to address issues in energy, environment, telecommunications and healthcare. In this quest, a class of two-dimensional layered materials consisting of alkali or coinage metal atoms sandwiched between slabs exclusively made of transition metal and chalcogen (or pnictogen) atoms arranged in a honeycomb fashion have emerged as materials exhibiting fascinatingly rich crystal chemistry, high-voltage electrochemistry, fast cation diffusion besides playing host to varied exotic electromagnetic and topological phenomena. Currently, with a niche application in energy storage as high-voltage materials, this class of honeycomb layered oxides serves as ideal pedagogical exemplars of the innumerable capabilities of nanomaterials drawing immense interest in multiple fields ranging from materials science, solid-state chemistry, electrochemistry and condensed matter physics.

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We report the successful synthesis, crystal structure, and electrical properties of SrReO, which contains Re with the 5d configuration. This compound is isostructural with BaReO and shows a first-order structural phase transition at ∼370 K. The low-temperature (LT) phase crystallizes in a hettotype structure of BaReO, which is different from that of the LT phase of SrWO, suggesting that the electronic state of Re plays an important role in determining the crystal structure of the LT phase.

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Psychometric intelligence is closely related to working memory (WM) and the associated brain activity. We aimed to clarify the associations between psychometric intelligence and WM-induced functional connectivity changes. Here we determined the associations between psychometric intelligence measured by nonverbal reasoning (using the Raven's Advanced Progressive Matrices) and WM-induced changes in functional connectivity during the N-back paradigm, in a large cohort of 1221 young adults.

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The crystal structure and magnetic properties of the cubic spinel MgFeMnO were studied by using a series of in-house techniques along with large-scale neutron diffraction and muon spin rotation spectroscopy in the temperature range between 1.5 and 500 K. The detailed crystal structure is successfully refined by using a cubic spinel structure described by the space group 3̅.

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