FGF-2 expansion of stem cells from inflamed pulp tissues of human deciduous teeth can be a good source of stem cells for future clinical applications and a novel way of using discarded inflamed tissues.

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ratory. About 85% of these obsidians originated from the Paektusan volcano (Korea); obsidian of Japanese origin was found only at Shinbuk. INAA analyses on 6 obsidian samples from the Hahwageri and Junghnugri sites are in good agreement with our PIXE results and those of the previous report by Popov et al. (2005).

This study presents the investigation of superconducting joints fabricated using multifilament magnesium diboride (MgB2) wires for the development of persistent-current mode magnetic resonance imaging (MRI) magnets. The critical current of the jointed samples decreased with increasing cutting angle because the smaller cutting angle allowed greater exposure of the MgB2 filament, thereby increasing the contact area for the wire-bulk-wire connection. In addition, an appropriate pressing pressure (300 MPa) was necessary to establish the multifilament MgB2 joint without significant degradation of superconducting properties. The resistance of the optimal MgB2 joint, measured using the field-decay technique, was <1.5 × 10−14 Ω. Therefore, the proposed joint technique can be employed for developing multifilament MgB2 MRI magnets operating in the persistent-current mode.

This note presents a superconducting joint technique for the development of MgB magnetic resonance imaging (MRI) magnets. The MgB superconducting joint was fabricated by a powder processing method using Mg and B powders to establish a wire-bulk-wire connection. The joint resistance measured using a field-decay method was <10 Ω, demonstrating that the proposed joint technique could be employed for developing "next-generation" MgB MRI magnets operating in the persistent current mode.

A large reduction of the ρ 0 mass in the nuclear medium is reported, inferred from dipion photoproduction spectra in the 1 GeV region, for the reaction 3 He(γ,π + π − )X with a 10% duty factor tagged-photon beam and the TAGX multi-particle spectrometer. The energy range covered (800≤Eγ ≤1120 MeV) lies mostly below the free ρ 0 production threshold, a region which is believed sensitive to modifications of light vector-meson properties at nuclear-matter densities. The ρ 0 masses extracted from the MC fitting of the data, m * ρ 0 = 642±40, 669±32, and 682±56 MeV/c 2 for Eγ in the 800-880, 880-960, and 960-1040 MeV regions respectively, are independently corroborated by a measured, assumption-free, kinematical observable. This mass shift, far exceeding current mean-1 field driven theoretical predictions, may be suggestive of ρ 0 decay within the range of the nucleonic field.

Amorphous Sm 2 Ti 2 O 7 ͑SmT͒ films were investigated to assess their potential use in metal-insulator-metal ͑MIM͒ capacitors. A 72 nm thick SmT film showed a high capacitance density of 5.2 fF/m 2 with a low leakage current density of 0.12 nA/cm 2 at 2.0 V. The capacitance density increased with decreasing film thickness to 8.18 fF/m 2 for the 46 nm thick film. The 72 nm thick SmT film had small quadratic and linear voltage coefficients of capacitance of 158 ppm/V 2 and −283 ppm/V, respectively, and a temperature coefficient of capacitance of 207 ppm/°C at 100 kHz. Overall, amorphous SmT films are good candidate materials for MIM capacitors.Metal-insulator-metal ͑MIM͒ capacitors with a high capacitance density are essential in order to miniaturize the chip size, which can be achieved by using dielectrics with a high dielectric constant ͑k͒. Therefore, many studies have been carried out to develop materials with a high k in an attempt to increase the capacitance density of MIM capacitors. Al 2 O 3 , HfO 2 , and Al 2 O 3 -HfO 2 laminate structure have been used as MIM capacitors. However, they have a low capacitance density or large quadratic voltage coefficient of capacitance ͑VCC͒. 1-4 ZrO 2 , Pr 2 O 3 films, and Nb 2 O 5 film with HfO 2 /Al 2 O 3 barriers were reported to have a high capacitance density but the other properties were not satisfactory. 5-7 Recently, the HfO 2 -SiO 2 stacked dielectric and Ti x Ta ͑1−x͒ O films were reported to have a high capacitance density with small VCCs. 8,9 Microwave dielectric materials, which have been used in microwave devices such as filters and resonators, usually have a high k value, a high quality factor ͑Q-factor͒, and good temperature stability. 10 Therefore, dielectric films made from these materials are good candidate materials for MIM capacitors. In particular, Sm 2 Ti 2 O 7 ͑SmT͒ microwave dielectric ceramics have a high-k value of 61 with a low tan ␦ value. 11 SmT films containing BaO as a second phase was obtained when the deposition temperature of the BaSm 2 Ti 4 O 12 film was low. 12 Moreover, a 100 nm thick crystalline SmT film grown at 200°C and annealed at 900°C had a capacitance density of 5.2 fF/m 2 with a very low leakage current of 1.34 nA/cm 2 at 2 V. 13 This SmT film also had a small linear and quadratic VCC of 11 ppm/V and −99.5 ppm/V 2 , respectively, with a low-temperature coefficient of capacitance ͑TCC͒ of 135 ppm/°C at 100 kHz. 13 Therefore, crystalline SmT films are considered good candidate materials for MIM capacitors. However, the process temperature used to grow the crystalline SmT films is too high for applications in back-end line integration. 12,13 Therefore, it is essential to grow homogeneous SmT films at low process temperatures in order for them to be used in MIM capacitors. In this study, homogeneous amorphous SmT films were grown at 200°C and their dielectric properties were investigated to assess their potential use in MIM capacitors. ExperimentalThe amorphous SmT films were grown on Pt/Ti/SiO 2 /Si͑100͒ substrates by radio freq...

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