Fast coherent control of nitrogen-14 spins associated with nitrogen-vacancy centers in diamonds using dynamical decoupling

A nitrogen-vacancy (NV) center in a diamond enables the access to an electron spin, which is expected to present highly sensitive quantum sensors. Although exploiting a nitrogen nuclear spin improves the sensitivity, manipulating it using a resonant pulse requires a long gate time owing to its small gyromagnetic ratio. Another technique to control nuclear spins is a conditional rotation gate based on dynamical decoupling, which is faster but unavailable for nitrogen spins owing to the lack of transverse hyperfine coupling with the electron spin. In this study, we generated effective transverse coupling by applying a weak off-axis magnetic field. An effective coupling depends on the off-axis field; the conditional rotation gate on the nitrogen-14 spins of an NV center was demonstrated within 4.2 {\mu}s under an 1.8% off-axis field and a longitudinal field of approximately 280 mT. We estimated that a population transfer from the electron to nitrogen spins can be implemented with 8.7 {\mu}s. Our method is applicable to an ensemble of NV centers, in addition to a single NV center

Iroquois homeobox 3 regulates odontoblast proliferation and differentiation mediated by Wnt5a expression

Iroquois homeobox (Irx) genes are TALE-class homeobox genes that are evolutionarily conserved across species and have multiple critical cellular functions in fundamental tissue development processes. Previous studies have shown that Irxs genes are expressed during tooth development. However, the precise roles of genes in teeth remain unclear. Here, we demonstrated for the first time that Irx3 is an essential molecule for the proliferation and differentiation of odontoblasts. Using cDNA synthesized from postnatal day 1 (P1) tooth germs, we examined the expression of all Irx genes (Irx1-Irx6) by RT-PCR and found that all genes except Irx4 were expressed in the tooth tissue. Irx1-Irx3 a were expressed in the dental epithelial cell line M3H1 cells, while Irx3 and Irx5 were expressed in the dental mesenchymal cell line mDP cells. Only Irx3 was expressed in both undifferentiated cell lines. Immunostaining also revealed the presence of IRX3 in the dental epithelial cells and mesenchymal condensation. Inhibition of endogenous Irx3 by siRNA blocks the proliferation and differentiation of mDP cells. Wnt3a, Wnt5a, and Bmp4 are factors involved in odontoblast differentiation and were highly expressed in mDP cells by quantitative PCR analysis. Interestingly, the expression of Wnt5a (but not Wnt3a or Bmp4) was suppressed by Irx3 siRNA. These results suggest that Irx3 plays an essential role in part through the regulation of Wnt5a expression during odontoblast proliferation and differentiation

Fast coherent control of nitrogen-14 spins associated with nitrogen-vacancy centers in diamonds using dynamical decoupling

A nitrogen-vacancy (NV) center in a diamond enables the access to an electron spin, which is expected to present highly sensitive quantum sensors. Although exploiting a nitrogen nuclear spin improves the sensitivity, manipulating it using a resonant pulse requires a long gate time owing to its small gyromagnetic ratio. Another technique to control nuclear spins is a conditional rotation gate based on dynamical decoupling, which is faster but unavailable for nitrogen spins owing to the lack of transverse hyperfine coupling with the electron spin. In this study, we generated effective transverse coupling by applying a weak off-axis magnetic field. An effective coupling depends on the off-axis field; the conditional rotation gate on the nitrogen-14 spins of an NV center was demonstrated within 4.2 μ s under an 1.8% off-axis field and a longitudinal field of approximately 280 mT. We estimated that a population transfer from the electron to nitrogen spins can be implemented with 8.7 μ s. Our method is applicable to an ensemble of NV centers, in addition to a single NV center

A novel mouse model of adult T-cell leukemia cell invasion into the spinal cord

Adult T‐cell leukemia (ATL) is a mature T‐cell malignancy caused by human T‐cell leukemia virus type I infection, and 10%‐25% of patients show central nervous system (CNS) involvement. CNS involvement significantly reduces survival and there are no effective treatments for CNS involvement. Therefore, an appropriate animal model is required to evaluate the inhibitory effects of novel drugs on the progression of ATL with CNS involvement. Here, we established a mouse model of ATL with CNS involvement using NOD.Cg‐Prkdc^Il2rg^/SzJ mice inoculated with ATL cells intramuscularly in the postauricular region, and these mice showed paraparesis. Of the 10 mice inoculated with ATL cells intramuscularly (I.M.) at 5 weeks of age, 8 (80%) showed paraparesis, whereas none of the 10 mice inoculated with ATL cells subcutaneously (S.C.) showed paraparesis. In the I.M. group, PCR detected HTLV‐1‐specific genes in the thoracic and lumbar vertebrae; however, in the S.C. group, the vertebrae were negative for HTLV‐1 genes. Histological analysis revealed a particularly high incidence of tumors, characterized by accumulation of the injected cells, in the thoracic vertebrae of mice in the I.M. group. Tumor cell infiltration was relatively high in the bone marrow. Spinal cord compression caused by invasion of the tumor mass outside the pia mater was observed in the thoracic vertebrae of the spinal cord. In conclusion, we have reported a mouse model of tumor growth with paraparesis that may be used to assess novel therapeutic agents for ATL with CNS involvement

Study on electron spin control method for high-sensitivity diamond quantum sensor

Study on electron spin control method for high-sensitivity diamond quantum sensorThe 4th International Forum on Quantum Metrology and Sensin

High dynamic range current detection using a diamond quantum sensor

The study on High dynamic range current detection using a diamond quantum sensorThe 4th International Forum on Quantum Metrology and Sensin