Utsunomiya University

About: Utsunomiya University is a education organization based out in Utsunomiya, Japan. It is known for research contribution in the topics: Laser & Holography. The organization has 4139 authors who have published 6812 publications receiving 91975 citations. The organization is also known as: Utsunomiya daigaku.

Analysis of β-ketothiolase and acetoacetyl-CoA reductase genes of a methylotrophic bacterium, Paracoccus denitrifleans, and their expression in Escherichia coli

Abstract: The β-ketothiolase gene (phaA) and acetoacetyl-CoA reductase gene (phaB) were isolated from Paracoccus denitrificans. Nucleotide sequence analysis showed that they encoded proteins of 391 amino acids with a molecular mass of 40744 Da and of 242 amino acids with a molecular mass of 25614 Da, respectively. The predicted gene products exhibited high amino acid identities with those from other bacteria: 64.4–74.0% for the phaA gene product and 47.6–80.6% for the phaB gene product, respectively. Both genes were co-transcribed in a recombinant Escherichia coli. In addition, promoter activity was detected upstream of the phaA gene. Hence, the two genes are organized as an operon, phaA-phaB, in P. denitrificans. NADH was preferred to NADPH as a cofactor of acetoacetyl-CoA reductase.

High temperature quantum paraelectricity in perovskite-type titanates Ln1/2Na1/2TiO3 (Ln = La, Pr, Nd, Sm, Eu, Gd and Tb)

Abstract: The La3+ ion of a quantum paraelectric perovskite La1/2Na1/2TiO3 was substituted with the smaller tripositive lanthanide ions Ln3+. The X-ray structural study and Rietveld refinement of Ln1/2Na1/2TiO3 for Ln=Pr to Tb showed that they are synthesized as orthorhombic perovskite structure with the space group Pnma. Their lattice parameters and dielectric constants decreased from Pr to Tb with an increasing volume of TiO6-octahedron. A high temperature quantum paraelectricity was found for Ln = Pr to Eu. Because of negative extrapolated Curie temperature, the process of explanation used for the typical quantum paraelectric SrTiO3 is not applicable to the quantum paraelectricity in Ln1/2Na1/2TiO3 for Ln = La ∼ Eu.

Constructive spin-orbital angular momentum coupling can twist materials to create spiral structures in optical vortex illumination

Abstract: It was discovered that optical vortices twist isotropic and homogenous materials, e.g., azo-polymer films to form spiral structures on a nano- or micro-scale. However, the formation mechanism has not yet been established theoretically. To understand the mechanism of the spiral surface relief formation in the azo-polymer film, we theoretically investigate the optical radiation force induced in an isotropic and homogeneous material under irradiation using a continuous-wave optical vortex with arbitrary topological charge and polarization. It is revealed that the spiral surface relief formation in azo-polymer films requires the irradiation of optical vortices with a positive (negative) spin angular momentum and a positive (negative) orbital angular momentum (constructive spin-orbital angular momentum coupling), i.e., the degeneracy among the optical vortices with the same total angular momentum is resolved.

A combination of calcium ionophore and puromycin effectively produces human parthenogenones with one haploid pronucleus.

Abstract: Parthenogenetic activation with various combinations of the calcium ionophore A23187 and protein synthesis or phosphorylation inhibitors was investigated as a means of producing human parthenogenones with one haploid pronucleus. Unfertilised human aged oocytes exposed to 5 μM A23187 for 5 min were treated with 10 μg/ml puromycin (puromycin group, 46 oocytes) or 2 mM 6-dimethylaminopurine (DMAP group, 42 oocytes) for 5 h. Oocytes treated only with A23187 served as a control (control group, 40 oocytes). After washing the oocytes, they were incubated for up to 37 h. Evidence of activation (pronuclear formation) and cleavage was observed 18 h and 42 h after A23187 treatment, respectively. Activation rates in the puromycin and DMAP groups were significantly higher than in the control group (91% (42/46) and 77% (34/44) vs 20% (8/40), p < 0.05, respectively). In the puromycin group, 81% (34/42) of the activated oocytes showed one pronucleus with the second polar body (2ndPB), whereas none (0/34) of the activated oocytes in the DMAP group extruded the 2ndPB. The cleavage rate in the puromycin group was significantly lower than in the DMAP group (38% vs 68%, p < 0.05). The activated oocytes which had one pronucleus with the 2ndPB in the puromycin group showed a haploid set of chromosomes (10/13). In conclusion, the combination of A23187 and puromycin is effective for producing human parthenogenones with one haploid pronucleus.

Adaptive optimization of a hologram in holographic femtosecond laser processing system.

Abstract: In holographic parallel laser processing, precise control of diffraction peaks is important for fabricating enormous numbers of nanometer-scale structures. Although an optimized hologram has high uniformity of the peaks in a computer reconstruction, in practice, the uniformity is decreased owing to the spatial properties of the optical system. A novel optimization method based on peak intensity measurement is proposed to improve the uniformity. The method automatically incorporates the properties of the optical system into the hologram. Improved holographic femtosecond laser processing with this adaptive optimization is demonstrated.