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The institutions and ethic committeeâ s reference number of this study. (DOCX 23Â kb)

The simultaneous occurrence of the structural and magnetic phase transitions observed in MnV2O4 is one clear example of strong interplay among the spin, orbital and lattice degrees of freedom. The structure of MnV2O4 is switched by the magnetic field and the linear magnetostriction is very high. The orbital order mediates the interaction between the spin and the lattice generating these phenomena. In this work, we present experimental evidence of an orbital order in MnV2O4 and its reorientation under a rotating magnetic field as obtained by nuclear magnetic resonance(NMR). The shift in the resonance frequency of the V NMR spectrum is symmetrical with respect to 45° as an external magnetic field of 7 T rotates from the c-axis to the b-axis, indicating that the initial easy axis flips to the orthogonal direction most parallel to the field direction. The spectrum of V3+ ions splits into four peaks with a maximum shift of 40 MHz. Our analysis revealed that this is the combined effect of the anisotropic hyperfine field due to an ordered orbital and the dipolar hyperfine field. Reorientation of the orbital order in response to an external magnetic field accompanies the macroscopically observed magnetostriction in MnV2O4.

The spin state of FeCl 3 was measured by Nuclear Magnetic Resonance (NMR) as a function of temperature and magnetic field. The sublattice magnetization obtained from the 57 Fe NMR spectrum fits well with the theoretical prediction for an antiferromagnet with a magnetic anisotropy field of less than 70 mT in the ab -plane. The field dependence of the 57 Fe NMR spectrum shows that a spin rotation plane of helical order starts to align perpendicularly to the external field direction as the field increases from 0 and ends around 4 T with no phase transition. From the spin tilting angle analysis, we obtained the quantitative relation among the exchange coupling constants.

The chinstrap (Pygoscelis antarcticus) and gentoo (P. papua) penguins are distributed throughout Antarctica and the sub-Antarctic islands. In this study, high-quality de novo assemblies of blood transcriptomes from these penguins were generated using the Illumina MiSeq platform. A total of 22.2 and 21.8 raw reads were obtained from chinstrap and gentoo penguins, respectively. These reads were assembled using the Oases assembly platform and resulted in 26,036 and 21,854 contigs with N50 values of 929 and 933 base pairs, respectively. Functional gene annotations through pathway analyses of the Gene Ontology, EuKaryotic Orthologous Groups, and Kyoto Encyclopedia of Genes and Genomes (KEGG) databases were performed for each blood transcriptome, resulting in a similar compositional order between the two transcriptomes. Ortholog comparisons with previously published transcriptomes from the Adélie (P. adeliae) and emperor (Aptenodytes forsteri) penguins revealed that a high proportion of the four penguins’ transcriptomes had significant sequence homology. Because blood and tissues of penguins have been used to monitor pollution in Antarctica, immune parameters in blood could be important indicators for understanding the health status of penguins and other Antarctic animals. In the blood transcriptomes, KEGG analyses detected many essential genes involved in the major innate immunity pathways, which are key metabolic pathways for maintaining homeostasis against exogenous infections or toxins. Blood transcriptome studies such as this may be useful for checking the immune and health status of penguins without sacrifice.

In this study, we determined the complete chloroplast (cp) genomes from two varieties of Cannabis sativa. The genome sizes were 153,848 bp (the Korean non-drug variety, Cheungsam) and 153,854 bp (the African variety, Yoruba Nigeria). The genome structures were identical with 131 individual genes [86 protein-coding genes (PCGs), eight rRNA, and 37 tRNA genes]. Further, except for the presence of an intron in the rps3 genes of two C. sativa varieties, the cp genomes of C. sativa had conservative features similar to that of all known species in the order Rosales. To verify the position of C. sativa within the order Rosales, we conducted phylogenetic analysis by using concatenated sequences of all PCGs from 17 complete cp genomes. The resulting tree strongly supported monophyly of Rosales. Further, the family Cannabaceae, represented by C. sativa, showed close relationship with the family Moraceae. The phylogenetic relationship outlined in our study is well congruent with those previously shown for the order Rosales.

The ${}^{55}$Mn nuclear magnetic resonance spectrum for the spinel oxide Mn${}_{3}$O${}_{4}$ was measured at low temperature to investigate the spin structure in the ground state. The spectrum consists of three peaks in the frequency range of 250--265 MHz, which corresponds to the hyperfine field range of 24--25 T. The temperature dependence of the spectrum and the rf enhancement factor show that Mn${}^{3+}$ ions have two different magnetic moments, one of which is strongly related to the commensurate-incommensurate phase transition. This is consistent with the picture of two magnetic moments $R$ and $S$ claimed from the results of a neutron experiment. Comparison with a heat-treated sample suggests a relation between the two different magnetic moments and the occupation sites of manganese ions, the tetrahedral and octahedral sites. Theoretical estimations of the dipolar hyperfine field and the observed peak splitting predict that the magnetic moments of $R$ and $S$ differ by 5$%$ at maximum. The spin-spin relaxation time has a frequency dependence that induces spectrum broadening and further splitting of the peak coming from $S$, indicating that the Suhl-Nakamura interaction is the major relaxation mechanism in Mn${}_{3}$O${}_{4}$.

The magnetoelectric properties of hexaferrite Ba0.5Sr1.5Zn2Fe12O22 are significantly improved by Al substitution and thermal annealing. Measuring the enhancement factor of 57Fe NMR, we found direct microscopic evidence that the magnetic moments of the L and S blocks are rotated by a magnetic field in such a way as to increase the net magnetic moment of a magnetic unit, even after the field is removed. Al substitution makes magnetoelectric property arise easily by suppressing the easy-plane anisotropy. The effect of thermal annealing is to stabilize the multiferroic state by reducing the number of pinning sites and the electron spin fluctuation. The transverse conic structure gradually changes to the alternating longitudinal conic structure where spins fluctuate more severely.

The zero-field 55 Mn nuclear magnetic resonance (NMR) spectra for antiferromagnetic -Mn2O3 were obtained at low temperatures. The Gaussian- shaped spectrum was positioned around 314MHz in the zero-temperature limit, and the linewidth was about 5MHz. The magnetic moment estimated from the resonance frequency was 2.6µB per Mn 3+ ion, which corresponds to 65% of 4µB, which is expected when only the contribution of spin to the magnetic moment is considered. The temperature dependence of the sublattice magnetization does not fit Bloch's T 2 law well but instead fits the exponential form applicable when there is an initial energy gap in the dispersion relation of the spin wave. From the fitting, we obtained an energy gap of 1.82meV and an anisotropy energy of 0.22meV. The spin-spin relaxation time measured as a function of frequency shows that the Suhl-Nakamura interaction is suppressed by this energy gap. The line broadening is mostly influenced by the dipolar hyperfine interaction.