13197 research outputs found
Sort by
The transmembrane protein TMEM196 controls cell proliferation and determines the floor plate cell lineage
No full textThe neural tube, the embryonic precursor to the vertebrate central nervous system, comprises distinct progenitor and neuronal domains, each with specific proliferation programs. In this study, we identified TMEM196, a novel transmembrane protein that plays a crucial role in regulating cell proliferation in the floor plate in chick embryos. TMEM196 is expressed in the floor plate, and its overexpression leads to reduced cell proliferation without affecting the pattern formation of the neural tube. We also established the floor plate differentiation protocol of the mouse embryonic stem cells, and analyzed the function of TMEM196 with this system. Mutating the Tmem196 gene does not alter cell division and overall differentiation remains unchanged within the neural cells. However, TMEM196 inhibits Wnt signaling, and Tmem196 mutant cells exhibit aberrant paraxial mesoderm differentiation, suggesting that TMEM196 selects the floor plate cell fate at the binary decision of the neuromesodermal cells. These findings highlight TMEM196 as a key regulator of both cell proliferation and floor plate determination, contributing to proper regionalization during embryogenesis.journal articl
Impact of Naphthalimide-Fusion Positions on Properties of Azulene Derivatives
No full textIn the Suzuki–Miyaura–Heck condensation reaction of 1-borylazulene with 4,5-dibromo-1,8-naphthalimide, we found the formation of naphthalimide-fused azulene at 1,8-positions (1,8-NIA) in 49% yield and an unexpected 1,2-fused product (1,2-NIA) in 6% yield, respectively. 1,2-NIA involves a pentalene skeleton at the central part and was characterized using NMR and single-crystal X-ray analysis. The condensation positions significantly affect their UV–vis–NIR absorption spectra: the absorption maximum of 1,8-NIA is 862 nm longer than that of 1,2-NIA (739 nm). TD-DFT calculations were performed to elucidate these electronic structures and revealed the effective π-elongation strategy.journal articl
Construction of a computational model of individual progression of motion sickness symptoms based on subjective vertical conflict theory
No full textComputational models predicting motion sickness have advanced, particularly those based on subjective vertical conflict (SVC) theory. While SVC-based models primarily predict motion sickness incidence (MSI), which is defined as the percentage of people who would vomit under a given motion, models predicting milder individual symptoms, which are crucial for daily applications, are still required. Recently, computational models predicting vestibular motion-sickness progression using the SVC theory have been developed by changing the output of a 6DOF-SVC model from MSI to the Misery Scale (MISC), a subjective measure of symptom progression. In practical applications, the ability to predict MISC for unseen motions is crucial. The present study conceived a method for predicting MISC beyond a certain point in the future by identifying parameters from data collected up to that point. Therefore, this study investigates the effect of the number of data points used for parameter identification on the future prediction accuracy. Observed MISC responses from participants exposed to linear lateral motion in darkness were used for model validation. The results indicated that prediction accuracy increased as more data points were included. On average, using more than 5–10 min of data significantly increased the accuracy compared to a model using averaged parameter sets across participants, although the tendency significantly differed based on an individual’s MISC history. A trial considering individual MISC histories, in which data points were defined when the observed MISC first reached certain levels, showed a general trend of improved accuracy when data up to MISC Level 3 was used. The findings of this study demonstrate that motion sickness symptom progression can be predicted with reduced error by incorporating individual symptom histories, thereby providing a foundation for the development of personalized motion sickness prediction models applicable to broader applications.journal articl
Synergistic Effects of Astaxanthin and Chlorophyll a on Singlet Oxygen Quenching Reinforced by Calcium Ascorbate
No full textThis study examines the synergistic effects of astaxanthin and chlorophyll a in quenching singlet oxygen (1O2). The 1O2 quenching rate constant of chlorophyll a is 1.72 × 1010 M–1 s–1, but it increases to 3.17 × 1010 M–1 s–1 in the presence of astaxanthin. The strongest synergistic effect occurs at a molar ratio of astaxanthin:chlorophyll a = 1:2. 1H NMR analysis revealed shifts in signals and changes in the longitudinal relaxation time (T1) of astaxanthin upon the addition of chlorophyll a, indicating their proximity and interaction, which were also supported by fluorescence quenching analysis. Further addition of 150 equimolar calcium ascorbate protects more than 95% of both antioxidants from thermal decomposition (60 °C, 1 h). The optimal molar ratio of astaxanthin, chlorophyll a, and calcium ascorbate is 1:2:150, maximizing the synergistic effect of astaxanthin and chlorophyll a, while calcium ascorbate reinforces 1O2 quenching by providing a reductive environment and long-term stability.journal articl
Local-structure insight into the improved superconducting properties of Pb-substituted La(O, F)BiS2: a photoelectron holography study
No full textPb-substituted La(O, F)BiS2 (Pb-LaOFBiS2) exhibits improved superconducting properties and a resistivity anomaly around 100 K that is attributed to a structural transition. We have performed temperature(T)-dependent photoelectron holography (PEH) to study dopant incorporation sites and the local structure change across the anomaly. The PEH study of Pb-LaOFBiS2 provided evidence for the dominant incorporation sites of Pb and F: Pb atoms are incorporated into the Bi sites and F atoms are incorporated into the O site. No remarkable difference in the local structures around Pb and Bi atoms was observed. Across the temperature of the resistivity anomaly (T*), photoelectron holograms of Bi 4f changed. Comparisons of holograms with those of non-substituted LaOFBiS2 sample, as well as simulated holograms, suggested that (1), above T*, the tetragonal structure of Pb-LaOFBiS2 is different from the tetragonal structure of LaOFBiS2 and (2), below T*, the tetragonal structure still remains in Pb-LaOFBiS2. We discuss a possible origin of the difference in the structure above T* and the implication of the result below T*, which are necessary ingredients to understand the physical properties of Pb-LaOFBiS2.journal articl
Damping rate of Josephson plasmons induced by coupling to amplitude modes in a current-carrying state
Get PDFWe consider the contribution of the amplitude mode to the damping rate of the Josephson plasmon. When a finite phase difference is present owing to the super-current through the junction, the broken time-reversal symmetry causes a finite coupling between the Josephson plasmon and amplitude mode. The strength of this coupling varies depending on the value of the phase difference, and the effect of the amplitude mode on the damping rate also depends on this phase difference. The damping rate becomes larger with increasing this coupling, and this results in the phase-difference dependence which is opposite to that obtained with use of the dissipation current due to quasiparticles by the previous theory. This effect leads to a theoretical explanation for previous experiments, including the damping rate near the transition temperature.conference pape
Experimental and Theoretical Factors in CO2 Reduction on Pd-Based Electrocatalysts and their Applicability for Integration with Data Science and High-Throughput Experiments
Get PDFThis review showcases crucial factors in mechanisms of electrochemical CO2 reduction by taking Pd-based electrocatalysts (mainly, monometallic Pd and Pd-based alloy nanoparticles) as examples. There are dependencies of experimental conditions (e.g., applied potentials) and constituent elements of the electrocatalysts on the reduction products of electrochemical CO2 reduction. Moreover, Pd-based electrocatalysts have unique characteristics in electrochemical CO2 reduction: alteration in selectivities for CO and HCOOH formations by applied potentials, almost no overpotential for HCOOH formation, deactivation of their electrocatalyses by poisoning with CO formed through CO2 reduction, and in situ formation of palladium hydride. Here, we survey the characteristics of Pd-based electrocatalysts in terms of experimental and theoretical insights. Then, it is described that formation energies of intermediates estimated by density functional theory calculations are understandable factors to explain experimental performances of Pd-based electrocatalysts. Considering the estimated factors, this review exhibits a perspective of utilization of the factors to advance the research activity of electrochemical CO2 reduction to its new horizon by using data science and high-throughput experiments.journal articl
Hierarchical Human Demonstration Toward Imitation Learning of Generalist Robot Planner
Get PDF奈良先端科学技術大学院大学博士（工学）doctoral thesi
The clock genes, PRRs, regulate phototropin-mediated blue-light responses in Arabidopsis thaliana
Get PDF奈良先端科学技術大学院大学博士（ﾊﾞｲｵｻｲｴﾝｽ）doctoral thesi