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The purely phase-constant-nonreciprocal composite right-left handed metamaterial structure is proposed based on coplanar waveguides loaded with a ferrite layer. The structure exhibits considerably large nonreciprocity in phase constant which depends on the effective magnetization and whose magnitude can remain in leaky wave region of wavenumbers or can overcome a boundary to slow wave region. The nonreciprocity in amplitude of transmission coefficients, on the other hand, is effectively reduced by using a cavity-backed design to prevent undesired nonreciprocal radiation loss. [ABSTRACT FROM AUTHOR]

This review introduces and overviews electromagnetism in structured metamaterials which undergo simultaneous time-reversal and space-inversion symmetry breaking due to magnetism and chirality. Direct experimental observation of optical magnetochiral effects in a single metamolecule with magnetism and chirality is demonstrated at microwave frequencies. Numerical simulations based on a finite element method reproduce the experimental results well, and predict the emergence of giant magnetochiral effects, by combining resonances in the metamolecule. Toward the realization of magnetochiral effects at higher frequencies than microwaves, a metamolecule is miniaturized in the presence of ferromagnetic resonance in a cavity and coplanar waveguide. This work opens the door to the realization of a one-way mirror and synthetic gauge fields for electromagnetic waves. [ABSTRACT FROM AUTHOR]

The effectiveness of long-term administration of tolvaptan in heart failure (HF) patients with chronic kidney disease (CKD) has not been fully studied. Hence, in this study, we investigated the effects of chronic administration of tolvaptan on patients with HF and CKD. We consecutively enrolled 31 patients with acute HF syndrome (AHFS) who were administrated tolvaptan as a long-term medication (TLV group). All patients had a history of prior HF admission and CKD. We also consecutively enrolled 27 patients with AHFS, a prior history of HF and CKD (conventional group). We compared renal function and outcomes between the two groups at discharge for AHFS and after 6 months of followup. The estimate glomerular filtration rate (eGFR) was maintained at approximately the same level in the TLV group exhibited approximately the same eGFR (-1.1 ± 8.3 mL/ min/1.73 m2) but decreased in the conventional group (-7.4 ± 10.4 mL/min/1.73 m2). There was a significant difference in the changes observed in eGFR between the conventional and TLV groups (p = 0.01). There were no significant differences in the frequencies of rehospitalization and death. Long-term administration of tolvaptan may prevent increased renal dysfunction in HF patients with CKD. This conclusion should be confirmed in a largescale prospective study. [ABSTRACT FROM AUTHOR]

We report direct observation of magnetochiral (MCh) effects for the X-band microwaves through a single metamolecule consisting of a copper chiral structure and ferrite rod. A fictitious interaction between chirality and magnetism is realized in the metamolecule without intrinsic electronic interactions. The MCh effects are induced at the resonant optical activities by applying a weak dc magnetic field of 1 mT, and are increased with the magnetic field. The nonreciprocal differences in refractive indices are evaluated to be 10-3 at 200 mT. [ABSTRACT FROM AUTHOR]

This study observes microwave beam splitting dependent on circular polarizations through nonuniform chiral metamaterials. Nonuniform chiral metamaterials with a gradation in refractive index are constructed using chiral meta-atoms that exhibit optical activities at microwave frequencies. Microwave scattering far-field patterns by the nonuniform chiral metamaterials demonstrate a deflection of microwaves, which transmit in a direction perpendicular to the refractive index gradient. Furthermore, circularly polarized microwaves with opposite "spins of light" go their separate ways in the nonuniform chiral metamaterials. This phenomenon is an optical analog of the Stern-Gerlach effects for electrons. [ABSTRACT FROM AUTHOR]

We have experimentally and numerically studied the directional birefringence of X-band microwaves by magnetochiral (MCh) effects of a single metamolecule under dc magnetic fields at room temperature. Phase and amplitude transmission coefficients from top and bottom, i.e., S parameters of S21 and S12, are measured for the single metamolecule consisting of a copper chiral structure and ferrite cylinder in a waveguide. By applying a dc magnetic field, we observe a difference between S21 and S12, which is an emergence of the MCh effects with simultaneous space-inversion and time-reversal symmetry breaking. Numerical calculation based on a finite element method reproduces well the experimental results of the MCh effects. The MCh effect can be enhanced by using the magnetic resonance of the ferrite cylinder. Notably, numerical calculation predicts that the MCh effect is extremely enhanced by interacting magnetic resonance with a specific resonant structural optical activity, leading to a giant MCh effect. The giant MCh effect observed in the present study originates from the one-way transparency caused by the Fano resonance in the metamolecule. [ABSTRACT FROM AUTHOR]