We collected and completely sequenced 28,469 full-length complementary DNA clones from Oryza sativa L. ssp. japonica cv. Nipponbare. Through homology searches of publicly available sequence data, we assigned tentative protein functions to 21,596 clones (75.86%). Mapping of the cDNA clones to genomic DNA revealed that there are 19,000 to 20,500 transcription units in the rice genome. Protein informatics analysis against the InterPro database revealed the existence of proteins presented in rice but not in Arabidopsis. Sixty-four percent of our cDNAs are homologous to Arabidopsis proteins.

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We report measurements of low-temperature specific heat on the 4f 2 -based heavy-fermion superconductor PrOs 4 Sb 12 . In magnetic fields above 4.5 T in the normal state, distinct anomalies are found which demonstrate the existence of a field-induced ordered phase (FIOP). The Pr nuclear specific heat indicates an enhancement of the 4f magnetic moment in the FIOP. Utilizing a Maxwell relation, we conclude that anomalous entropy, which is expected for a single-site quadrupole Kondo model, is not concealed below 0.16 K in zero field. We also discuss two possible interpretations of the Schottky-like anomaly at $3 K, i.e., a crystalline-field excitation or a hybridization gap formation.The f -electron-related heavy fermion (HF) systems exhibiting superconductivity had previously been found only in Ce and U intermetallic compounds. Therefore, the recent observation of the first Pr-based heavy fermion superconductivity (HFSC) in a filled skutterudite PrOs 4 Sb 12 1) has profound scientific significance. The 4f 2 configuration of Pr ions in intermetallic compounds had been considered to be quite stable in view of there being no observation of strongly correlated electron behaviors until recent studies on PrInAg 2 2) and PrFe 4 P 12 , 3-5) in which this picture breaks down. In PrFe 4 P 12 , which is also a member of the filled skutterudites, we have shown by specific heat, 3) electrical resistivity 4) and de Haas-van Alphen (dHvA) effect measurements 5) that HF behaviors appear in high fields where a nonmagnetic ordered state, probably of quadrupole origin, is suppressed. To our knowledge, PrFe 4 P 12 is the only system for which such definitive evidence for the 4f 2 -based Fermi-liquid HF ground state has been obtained.Compelling evidence for the HFSC in PrOs 4 Sb 12 was given by a large specific heat jump ÁC=T ¼ 0:5 J/K 2 mol at T c ¼ 1:85 K on a pellet of compressed powdered single crystals. 1) The jump is superimposed on a Schottky-like anomaly appearing at $3 K. Bauer et al. 1) attributed this peak to a doublet-triplet (À 3 -À 5 in O h -type notation) crystalline-electric-field (CEF) thermal excitation, taking into account their magnetic susceptibility ðTÞ and inelastic neutron scattering data. Since the À 3 non-Kramers doublet ground state has quadrupole degrees of freedom, they pointed out the possibility that the HF behavior is associated with a quadrupolar Kondo effect 6) on the Pr-ion lattice. In order to confirm this scenario, it is essential to clarify how the entropy R ln 2 associated with the À 3 ground state is released and whether any residual entropy is hidden far below T c or not.In this letter, we report two important findings in PrOs 4 Sb 12 , based on specific heat and magnetization measurements on high-quality single crystalline samples:(1) clear evidence for the existence of a field-induced ordered phase (FIOP) and (2) confirmation that no anomalous entropy is concealed below 0.16 K in zero field.Single crystals of the filled skutterudite PrOs 4 Sb 12 and the reference compound LaOs 4 Sb 12 were gro...

Specific heat and magnetization measurements have been performed on high-quality single crystals of filled-skutterudite PrFe4P12 in order to study the high-field heavy fermion state (HFS) and low-field ordered state (ODS). From a broad hump observed in C/T vs T in HFS for magnetic fields applied along the 100 direction, the Kondo temperature of ∼ 9 K and the existence of ferromagnetic Pr-Pr interactions are deduced. The 141 Pr nuclear Schottky contribution, which works as a highly-sensitive on-site probe for the Pr magnetic moment, sets an upper bound for the ordered moment as ∼ 0.03µB /Pr-ion. This fact strongly indicates that the primary order parameter in the ODS is nonmagnetic and most probably of quadrupolar origin, combined with other experimental facts. Significantly suppressed heavy-fermion behavior in the ODS suggests a possibility that the quadrupolar degrees of freedom is essential for the heavy quasiparticle band formation in the HFS. Possible crystalline-electric-field level schemes estimated from the anisotropy in the magnetization are consistent with this conjecture. 71.27.+a, 75.40.Cx, 71.70.Jp, 71.70.Ch

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