We introduce a cluster extension of multipole moments to discuss the anomalous Hall effect (AHE) in both ferromagnetic (FM) and antiferromagnetic (AFM) states in a unified framework. We first derive ...general symmetry requirements for the AHE in the presence or absence of the spin-orbit coupling by considering the symmetry of the Berry curvature in k space. The cluster multipole (CMP) moments are then defined to quantify the macroscopic magnetization in noncollinear AFM states as a natural generalization of the magnetization in FM states. We identify the macroscopic CMP order which induces the AHE. The theoretical framework is applied to the noncollinear AFM states of Mn3Ir , for which an AHE was predicted in a first-principles calculation, and Mn3Z (Z = Sn, Ge) , for which a large AHE was recently discovered experimentally. We further compare the AHE in Mn3Z and bcc Fe in terms of the CMP. We show that the AHE in Mn3Z is characterized by the magnetization of a cluster octupole moment in the same manner as that in bcc Fe characterized by the magnetization of the dipole moment.
Conspectus The synthesis of organic chemicals from H2O and CO2 using solar energy is important for recycling CO2 through cyclical use of chemical ingredients produced from CO2 or molecular energy ...carriers based on CO2. Similar to photosynthesis in plants, the CO2 molecules are reduced by electrons and protons, which are extracted from H2O molecules, to produce O2. This reaction is uphill; therefore, the solar energy is stored as the chemical bonding energy in the organic molecules. This artificial photosynthetic technology mimicking green vegetation should be implemented as a self-standing system for on-site direct solar energy storage that supports CO2 recycling in a circular economy. Herein, we explain our interdisciplinary fusion methodology to develop hybrid photocatalysts and photoelectrodes for an artificial photosynthetic system for the CO2 reduction reaction (CO2RR) in aqueous solutions. The key factor for the system is the integration of uniquely different functions of molecular transition-metal complexes and solid semiconductors. A metal complex catalyst and a semiconductor appropriate for a CO2RR and visible-light absorption, respectively, are linked, and they function complementary way to catalyze CO2RR under visible-light irradiation as a particulate photocatalyst dispersion in solution. It has also been proven that Ru complexes with bipyridine ligands can catalyze a CO2RR as photocathodes when they are linked with various semiconductor surfaces, such as those of doped tantalum oxides, doped iron oxides, indium phosphides, copper-based sulfides, selenides, silicon, and others. These photocathodes can produce formate and carbon monoxide using electrons and protons extracted from water through potential-matched connections with photoanodes such as TiO2 or SrTiO3 for oxygen evolution reactions (OERs). Benefiting from the very low overpotential of an aqueous CO2RR at metal complexes approaching the theoretical lower limit, the semiconductor/molecule hybrid system demonstrates a single tablet-formed monolithic electrode called “artificial leaf.” This single electrode device can generate formate (HCOO–) from H2O and CO2 in a water-filled single-compartment reactor without requiring a separation membrane under unassisted or bias-free conditions, either electrically or chemically. The reaction proceeds with a stoichiometric electron/hole ratio and stores solar energy with a solar-to-chemical energy conversion efficiency of 4.6%, which exceeds that of plants. In this Account, the key results that marked our milestones in technological progress of the semiconductor/molecule hybrid photosystem are concisely explained. These results include design, proof of the principle, and understanding of the phenomena by time-resolved spectroscopies, synchrotron radiation analyses, and DFT calculations. These results enable us to address challenges toward further scientific progress and the social implementation, including the use of earth-abundant elements and the scale-up of the solar-driven CO2RR system.
The genomes of many animals, plants and fungi are tagged by methylation of DNA cytosine. To understand the biological significance of this epigenetic mark it is essential to know where in the genome ...it is located. New techniques are making it easier to map DNA methylation patterns on a large scale and the results have already provided surprises. In particular, the conventional view that DNA methylation functions predominantly to irreversibly silence transcription is being challenged. Not only is promoter methylation often highly dynamic during development, but many organisms also seem to target DNA methylation specifically to the bodies of active genes.
We propose a systematic method to generate a complete orthonormal basis set of multipole expansion for magnetic structures in arbitrary crystal structure. The key idea is the introduction of a ...virtual atomic cluster of a target crystal on which we can clearly define the magnetic configurations corresponding to symmetry-adapted multipole moments. The magnetic configurations are then mapped onto the crystal so as to preserve the magnetic point group of the multipole moments, leading to the magnetic structures classified according to the irreducible representations of the crystallographic point group. We apply the present scheme to pyrochlore and hexagonal ABO3 crystal structures and demonstrate that the multipole expansion is useful to investigate the macroscopic responses of antiferromagnets.
The objective of this study was to investigate changes in physical activity (PA) between January (before the COVID-19 epidemic) and April (during the COVID-19 epidemic) 2020 in community-dwelling ...older adults in Japan.
Cross-sectional online survey.
From April 23 to 27, 2020, an online survey was completed by 1,600 community-dwelling older adults in Japan.
We assessed the frailty status using the Kihon checklist, and other demographics and asked questions regarding PA at two time points: January and April 2020. We defined the total PA time (minutes) per week based on activity frequency and time.
The study participants' mean age, proportion of women, and prevalence of frailty were 74.0±5.6 years, 50% (n=800), and 24.3% (n=388), respectively. We found a significant decrease in total PA time in April 2020 (median interquartile range (IQR), 180 0 to 420) when compared to January 2020 (median IQR, 245 90 to 480) (P<0.001). We also performed a subgroup analysis according to the frailty category; total PA time significantly decreased in April 2020 when compared to January 2020 for all frailty categories (P<0.001).
In conclusion, due to the COVID-19 epidemic, the total PA time in April 2020 significantly decreased compared to that in January 2020 in older adults. This finding may lead to a higher incidence of disability in the near future in older people.
Objectives
The objective of this study was to investigate changes in physical activity (PA) between January (before the COVID-19 epidemic) and April (during the COVID-19 epidemic) 2020 in ...community-dwelling older adults in Japan.
Design
Cross-sectional online survey.
Setting and Subjects
From April 23 to 27, 2020, an online survey was completed by 1,600 community-dwelling older adults in Japan.
Methods
We assessed the frailty status using the Kihon checklist, and other demographics and asked questions regarding PA at two time points: January and April 2020. We defined the total PA time (minutes) per week based on activity frequency and time.
Results
The study participants’ mean age, proportion of women, and prevalence of frailty were 74.0±5.6 years, 50% (n=800), and 24.3% (n=388), respectively. We found a significant decrease in total PA time in April 2020 (median interquartile range (IQR), 180 0 to 420) when compared to January 2020 (median IQR, 245 90 to 480) (P<0.001). We also performed a subgroup analysis according to the frailty category; total PA time significantly decreased in April 2020 when compared to January 2020 for all frailty categories (P<0.001).
Conclusion
In conclusion, due to the COVID-19 epidemic, the total PA time in April 2020 significantly decreased compared to that in January 2020 in older adults. This finding may lead to a higher incidence of disability in the near future in older people.
The naphthol reds are a family of intermediate performance monoazo organic pigments and three of its members, C.I. Pigment Red 148, C.I. Pigment Red 170 (Naphthol Red), and C.I. Pigment Red 188, have ...been cited as having original automotive paint applications. This study sought to determine which were used in North American vehicle original finishes (1974 to 2019) and how they can be differentiated and identified in situ in paint infrared spectra. Naphthol Red was the only such pigment found and based on a comprehensive survey, absorptions of this pigment were identified in spectra of 12 of the 373 (3%) red or maroon nonmetallic original finishes examined. Identification of Naphthol Red in an unknown finish can thus serve to limit the number of possible source vehicles and spectra of the twelve are presented to facilitate this examination, along with a list of the vehicles that the twelve were used on. For a comparative analysis, identification of this pigment in questioned and known specimens may provide some means of assessing the significance of the finding. Two Inmont red nonmetallic acrylic melamine basecoats, one of which contains Naphthol Red, were found to have quite unusual infrared spectra that are readily distinguished from those of the other 371 finishes examined, and they are discussed. Naphthol Red was also identified in some color‐coordinated automotive paint primers and its use appears to be more common in these than in the finish layers.
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