Call-by-Value and Call-by-Name Dual Calculi with Inductive and Coinductive Types

This paper extends the dual calculus with inductive types and coinductive types. The paper first introduces a non-deterministic dual calculus with inductive and coinductive types. Besides the same duality of the original dual calculus, it has the duality of inductive and coinductive types, that is, the duality of terms and coterms for inductive and coinductive types, and the duality of their reduction rules. Its strong normalization is also proved, which is shown by translating it into a second-order dual calculus. The strong normalization of the second-order dual calculus is proved by translating it into the second-order symmetric lambda calculus. This paper then introduces a call-by-value system and a call-by-name system of the dual calculus with inductive and coinductive types, and shows the duality of call-by-value and call-by-name, their Church-Rosser properties, and their strong normalization. Their strong normalization is proved by translating them into the non-deterministic dual calculus with inductive and coinductive types.Comment: The conference version of this paper has appeared in RTA 200

The complete amino acid sequences of the 5 S rRNA binding proteins L5 and L18 from the moderate thermophile Bacillus stearothermophilus ribosome

AbstractThe complete amino acid sequences of the 5 S rRNA binding proteins L5 and L18 isolated from ribosomes of the moderate thermophile Bacillus stearothermophilus are presented. This has been achieved by the sequence analysis of peptides derived by enzymatic digestions with trypsin, chymotrypsin, pepsin, and Staphy-lococcusaureus protease, as well as by chemical cleavage with cyanogen bromide. The proteins L5 and L18 consist of 179 and 120 amino acid residues, and have Mr values of 20 163 and 13 473, respectively. A comparison of the sequences with their counterparts from the Escherichia coli ribosome reveals 59% identical residues for L5, and 53% for L18. For both proteins, the distribution of conserved regions is not random along the protein chains: some regions are highly conserved while others are not. The regions which are conserved during evolution may be important for the interaction with the 5 S rRNA molecule

The complete amino acid sequence of ribosomal protein S12 from Bacillus stearothermophilus

AbstractThe amino acid sequence of ribosomal protein S12 from Bacillus stearothermophilus has been completely determined. The sequence data were mainly obtained by manual sequencing of peptides derived from digestion with trypsin, Staphylococcus aureas protease and pepsin. A few overlaps of tryptic peptides were established by DNA sequence analysis of a chromosomal fragment containing the rpsL gene coding for ribosomal protein S12. The protein contains 138 amino acid residues and has an Mr of 15208. Comparison of this sequence with the sequences of the ribosomal S12 proteins from E. coli as well as from Euglena, tobacco and liverwort chloroplasts shows that 75% of the amino acid residues are identical within the S12 proteins of all four species. Therefore, S12 is the most strongly conserved ribosomal protein known so far

Origin of opaque minerals in an unequilibrated enstatite chondrite, Yamato-691

This paper describes the petrographic and chemical features of opaque minerals in an unequilibrated enstatite chondrite, Yamato-691,and discusses the genetic relations among opaque minerals. Most of them occur in and/or around Fe-Ni metal. Opaque minerals formed from the primary metal alloy through various reactions such as exsolution and reaction with surrounding sulfur gas. The sequence of the formation is graphite, schreibersite, troilite with perryite and sphalerite in metal alloy. Niningerite and oldhamite formed independently and attached to the metal alloy at the high temperatures. The primary metal alloy had condensed in the nebula under a very low oxygen fugacity condition, and included P, Si, Cr, Mn and Ti, in addition to Fe, Ni and Co. The condensation sequences of minerals calculated previously under the oxygen depletion condition agree with the results obtained here in general. Fe-Ni metal frequently contains silicate inclusions which are mostly silica minerals. They formed later through the oxidization process of Fe-Ni metal under slightly more oxidizing conditions than the primary stage

Large-n Limit of N=2 Supersymmetric Q^n Model in Two Dimensions

We investigate non-perturbative structures of the two-dimensional N=2 supersymmetric nonlinear sigma model on the quadric surface Q^{n-2}(C) = SO(n)/SO(n-2)xU(1), which is a Hermitian symmetric space, and therefore Kahler, by using the auxiliary field and large-n methods. This model contains two kinds of non-perturbatively stable vacua; one of them is the same vacuum as that of supersymmetric CP^{n-1} model, and the other is a new kind of vacuum, which has not yet been known to exist in two-dimensional nonlinear sigma models, the Higgs phase. We show that both of these vacua are asymptotically free. Although symmetries are broken in these vacua, there appear no massless Nambu-Goldstone bosons, in agreement with Coleman's theorem, due to the existence of two different mechanisms in these vacua, the Schwinger and the Higgs mechanisms.Comment: LaTeX, 28 pages, 22 figures, published versio