We report on the nonlinear magnetization dynamics of a HoFeO 3 crystal induced by a strong terahertz magnetic field resonantly enhanced with a split ring resonator and measured with magneto-optical Kerr effect microscopy. The terahertz magnetic field induces a large change (∼40%) in the spontaneous magnetization. The frequency of the antiferromagnetic resonance decreases in proportion to the square of the magnetization change. A modified Landau-Lifshitz-Gilbert equation with a phenomenological nonlinear damping term quantitatively reproduced the nonlinear dynamics.

Although viruses have threatened our ancestors for millions of years, prehistoric epidemics of viruses are largely unknown. Endogenous bornavirus-like elements (EBLs) are ancient bornavirus sequences derived from the viral messenger RNAs that were reverse transcribed and inserted into animal genomes, most likely by retrotransposons. These elements can be used as molecular fossil records to trace past bornaviral infections. In this study, we systematically identified EBLs in vertebrate genomes and revealed the history of bornavirus infections over nearly 100 My. We confirmed that ancient bornaviral infections have occurred in diverse vertebrate lineages, especially in primate ancestors. Phylogenetic analyses indicated that primate ancestors were infected with various bornaviral lineages during evolution. EBLs in primate genomes formed clades according to their integration ages, suggesting that bornavirus lineages infected with primate ancestors had changed chronologically. However, some bornaviral lineages may have coexisted with primate ancestors and underwent repeated endogenizations for tens of millions of years. Moreover, a bornaviral lineage that coexisted with primate ancestors also endogenized in the genomes of some ancestral bats. The habitats of these bat ancestors have been reported to overlap with the migration route of primate ancestors. These results suggest that long-term virus–host coexistence expanded the geographic distributions of the bornaviral lineage along with primate migration and may have spread their infections to these bat ancestors. Our findings provide insight into the history of bornavirus infections over geological timescales that cannot be deduced from research using extant viruses alone, thus broadening our perspective on virus–host coevolution.

Excitation of antiferromagnetic resonance (AFMR) in a HoFeO3 crystal combined with a split ring resonator (SRR) is studied using terahertz (THz) electromagnetic pulses. The magnetic field in the vicinity of the SRR is induced by the incident THz electric field component and excites spin oscillations that correspond to the AFMR, which are directly probed by the Faraday rotation of the polarization of a near-infrared probe pulse. The good agreement of the temperature-dependent magnetization dynamics with the calculation using the two-lattice Landau-Lifshitz-Gilbert equation confirms that the AFMR is excited by the THz magnetic field, which is enhanced at the SRR resonance frequency by a factor of 20 compared to the incident magnetic field.

Approximately 1 in 2 Japanese people are estimated to be diagnosed with cancer during their lifetime. Cancer still remains the leading cause of death in Japan, therefore the government of Japan has decided to develop a better cancer control policy and launched the Cancer Genomic Medicine (CGM) program. The Ministry of Health, Labour, and Welfare (MHLW) held a consortium at their headquarters with leading academic authorities and the representatives of related organizations to discuss ways to advance CGM in Japan. Based on the report of the consortium, the CGM system under the national health insurance system has gradually been realized. Eleven hospitals were designated in February 2018 as core hospitals for CGM; subsequently, the MHLW built the Center for Cancer Genomics and Advanced Therapeutics (C‐CAT) as an institution to aggregate and manage genomic and clinical information on cancer patients, and support appropriate secondary use of the aggregated information to develop research aimed at medical innovation. As the first step in Japan's CGM in routine practice, in June 2019 the MHLW started reimbursement of 2 types of tumor profiling tests for advanced solid cancer patients using the national insurance system. Japan's CGM has swiftly been spreading nationwide with the collaboration of 167 hospitals and patients. The health and research authorities are expected to embody personalized cancer medicine and promote CGM utilizing state‐of‐the‐art technologies.