Electrons in conventional metals become less mobile under the influence of electron correlation. Contrary to this empirical knowledge, we report here that electrons with the highest mobility ever ...found in known bulk oxide semiconductors emerge in the strong-correlation regime of the Dirac semimetal of perovskite CaIrO
. The transport measurements reveal that the high mobility exceeding 60,000 cm
V
s
originates from the proximity of the Fermi energy to the Dirac node (ΔE < 10 meV). The calculation based on the density functional theory and the dynamical mean field theory reveals that the energy difference becomes smaller as the system approaches the Mott transition, highlighting a crucial role of correlation effects cooperating with the spin-orbit coupling. The correlation-induced self-tuning of Dirac node enables the quantum limit at a modest magnetic field with a giant magnetoresistance, thus providing an ideal platform to study the novel phenomena of correlated Dirac electron.
In water splitting by using heterogeneous photocatalysts, the use of a suitable cocatalyst has been recognized as one of the key factors in enhancing the photocatalytic activity. Although platinum is ...a representative cocatalyst for many heterogeneous photocatalytic reactions, it has not been used for photocatalytic water splitting, owing to its high catalytic activity for the reverse reaction of water splitting. In the present study, platinum nanoparticles were loaded as a cocatalyst on a calcium titanate photocatalyst by a conventional impregnation method and a photodeposition method and examined for photocatalytic water splitting in a flow of water vapor. Platinum nanoparticles loaded by the impregnation method were found to retain the oxidized form on the calcium titanate photocatalyst, even under photoirradiation, and promoted hydrogen and oxygen production by photocatalytic water vapor splitting without promoting the reverse reaction.
No turning back: A Pt cocatalyst on a CaTiO3 photocatalyst, prepared by a conventional impregnation method, works to produce hydrogen and oxygen from water vapor. The Pt species are in the oxidized state on the CaTiO3 surface and catalytically inactive for the reverse reaction, which allows the production of hydrogen and oxygen by photocatalytic water splitting.
Bmal1 is an essential transcriptional activator within the mammalian circadian clock. We report here that the suprachiasmatic nucleus (SCN) of Bmal1-null mutant mice, unexpectedly, generates ...stochastic oscillations with periods that overlap the circadian range. Dissociated SCN neurons expressed fluctuating levels of PER2 detected by bioluminescence imaging but could not generate circadian oscillations intrinsically. Inhibition of intercellular communication or cyclic-AMP signaling in SCN slices, which provide a positive feed-forward signal to drive the intracellular negative feedback loop, abolished the stochastic oscillations. Propagation of this feed-forward signal between SCN neurons then promotes quasi-circadian oscillations that arise as an emergent property of the SCN network. Experimental analysis and mathematical modeling argue that both intercellular coupling and molecular noise are required for the stochastic rhythms, providing a novel biological example of noise-induced oscillations. The emergence of stochastic circadian oscillations from the SCN network in the absence of cell-autonomous circadian oscillatory function highlights a previously unrecognized level of circadian organization.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Hayabusa2 was launched on 3 December 2014 on an H-IIA launch vehicle from the Tanegashima Space Center, and is, at the time of writing, cruising toward asteroid 162137 Ryugu (
1999
JU
3
). After ...reaching the asteroid, it will stay for about 1.5 years to observe the asteroid and collect surface material samples.
The light detection and ranging (LIDAR) laser altimeter on Hayabusa2 has a wide dynamic range, from 25 km to 30 m, because the LIDAR is used as a navigation sensor for rendezvous, approach, and touchdown procedures. Since it was designed for use in planetary explorers, its weight is a low 3.5 kg. The LIDAR can serve not only as a navigation sensor, but also as observation equipment for estimating the asteroid’s topography, gravity and surface reflectivity (albedo). Since Hayabusa2 had a development schedule of just three years from the start of the project to launch, minimizing development time was a particular concern. A key to shortening the development period of Hayabusa2’s LIDAR system was heritage technology from Hayabusa’s LIDAR and the SELENE lunar explorer’s LALT laser altimeter.
Given that the main role of Hayabusa2’s LIDAR is to serve as a navigation sensor, we discuss its development from an engineering viewpoint. However, detailed information about instrument development and test results is also important for scientific analysis of LIDAR data and for future laser altimetry in lunar and planetary exploration. Here we describe lessons learned from the Hayabusa LIDAR, as well as Hayabusa2’s hardware, new technologies and system designs based on it, and flight model evaluation results. The monolithic laser used in the laser module is a characteristic technology of this LIDAR. It was developed to solve issues with low-temperature storage that were problematic when developing the LIDAR system for the first Hayabusa mission. The new module not only solves such problems but also improves reliability and miniaturization by reducing the number of parts.
We previously reported that transplantation (Tx) of prevascularized donor islets as composite islet‐kidneys (IK) reversed diabetic hyperglycemia in both miniature swine and baboons. In order to ...enhance this strategy's potential clinical applicability, we have now combined this approach with hematopoietic stem cell (HSC) Tx in an attempt to induce tolerance in nonhuman primates. IKs were prepared by isolating islets from 70% partial pancreatectomies and injecting them beneath the autologous renal capsule of five rhesus monkey donors at least 3 months before allogeneic IK Tx. HSC Tx was performed after mobilization and leukapheresis of the donors and conditioning of the recipients with total body irradiation, T cell depletion, and cyclosporine. One IK was harvested for histologic analysis and four were transplanted into diabetic recipients. IK Tx was performed either 20–22 (n = 3) or 208 (n = 1) days after HSC Tx. All animals accepted IKs without rejection. All recipients required >20 U/day insulin before IK Tx to maintain <200 mg/dL, whereas after IK Tx, three animals required minimal doses of insulin (1–3 U/day) and one animal was insulin free. These results constitute a proof‐of‐principle that this IK tolerance strategy may provide a cure for both end‐stage renal disease and diabetes without the need for immunosuppression.
The authors report the successful use of transient mixed hematopoietic chimerism to induce tolerance of composite islet‐kidneys across a one‐haplotype major histocompatibility complex barrier in rhesus monkeys.
The impact of electron correlation on the Dirac semimetal state is investigated for perovskite CaIrO3 in terms of the magnetotransport properties under varying pressures. The reduction of electron ...correlation with a pressure of 1 GPa enhances the Fermi velocity as much as 40%, but it reduces the mobility by an order of magnitude by detuning the Dirac node from the Fermi energy. Moreover, the giant magnetoresistance at the quantum limit due to the one-dimensional confinement of Dirac electrons is critically suppressed under pressure. These results indicate that the electron correlation is a crucial knob for controlling the transport of a correlated Dirac semimetal.
To identify longitudinal changes in life-space mobility and the factors influencing it among chronic, stable post-stroke patients.
This prospective study included Japanese post-stroke patients who ...received day-care rehabilitation services and could undergo three life-space mobility assessments (at baseline, 12, and 24 months) for over 2 years, using the Life-Space Assessment (LSA) tool. Physical function, cognitive function, and activities of daily living were assessed by self-selected comfortable gait speed, Mini-Mental State Examination (MMSE), and Functional Independence Measure Motor subscale (FIM motor) scores, respectively, in addition to age, sex, time from onset, stroke type, and comorbidities. A multivariable linear mixed-effects model was used to examine the longitudinal changes in LSA scores and associated factors.
A total of 89 participants were enrolled. At baseline, the median age was 74 years, 33% were women, and median time from onset was 75 months. The LSA scores significantly declined over the two-year period. In the multivariate linear mixed-effects model adjusted for clinical characteristics, comfortable gait speed and age were significantly associated with changes in the LSA score, independent of FIM motor scores and MMSE scores.
Life-space mobility may persistently decline, and gait function may be a determinant influencing these changes in community-dwelling chronic post-stroke patients.
Implications for Rehabilitation
Limited life-space mobility leads to less frequent participation in social activities and an increased risk of adverse health outcomes such as hospitalization.
Changes in life-space mobility should be considered in the rehabilitation care plan for chronic post-stroke patients.
Life-space mobility may decline persistently in stable post-stroke patients, even if they have periodically received day-care rehabilitation services.
Since gait speed is a predominant factor affecting life-space mobility, regular assessment of gait function and appropriate strategies are needed to prevent deterioration of gait speed in chronic post-stroke patients.
•Monodispersed Fe76Si9B10P5 particles were successfully prepared by our containerless process.•The cooling rates of obtained particles were estimated by a model based on Newton’s law of cooling.•The ...critical cooling rate to form the fully amorphous phase was estimated in less than 550K/s.•We revealed that the Fe76Si9B10P5 alloy has sufficient inherent glass-forming ability.
We aim to prepare monodispersed and homogenous spherical particles of pure Fe76Si9B10P5 metallic glass with a low content of nucleation sites, and to evaluate the intrinsic glass-forming ability of Fe76Si9B10P5 alloys by containerless solidification. Monodispersed Fe76Si9B10P5 particles were successfully prepared by our originally developed pulsated orifice ejection method under He and Ar gas atmosphere. All obtained particles, with diameters ranging from 313 to 664μm, were identified as single glassy or amorphous phases by X-ray diffraction, differential scanning calorimetry, and transmission electron microscopy. The critical cooling rate to form the fully glassy or amorphous phase was estimated in less than 550K/s by a Newtonian cooling model. The results show that the Fe76Si9B10P5 alloy has sufficient glass-forming ability under restrained nucleation conditions.
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