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8 Conca, A.; Herzog, J.; Hibi, T
(Graduate School of Information Science and Technology)
Rigid Resolutions and Big Betti Numbers
Commentarii Mathematici Helvetici, 79, 826-839 (2004)

This paper contributes to the development of computational commutative algebra. The Betti numbers of a graded ideal in a polynomial ring and the Betti numbers of its generic initial ideal are compared. In characteristic zero it is shown that if these Betti numbers coincide in some homological degree, then they coincide in all higher homological degrees. Moreover, the Betti numbers of componentwise linear ideals which are contained in each other and have the same Hilbert polynomial are compared.

9 Endo, N.*1; Taniguchi, K.*1; Katsuki, A.*1,2
*1 (Graduate School of Science) *2 (Cybermedia Center)
Observation of the Whole Process of Interaction between Barchans by Flume Experiments
Geophysical Research Letters, 31, L12503 (2004)

10 Fujioka, H.; Ohba, Y.; Hirose, H.; Murai, K.; Kita, Y.
(Graduate School of Pharmaceutical Sciences)
A Double Iodoetherification of σ-Symmetric Diene Acetals for Installing Four Stereogenic Centers in Single Operation: Short Asymmetric Total Synthesis of Rubrenolide
Angewandte Chemie International Edition, 44, 734-737 (2005)

Tetrahydrofuran units with multiple chiral centers are formed in a highly diastereoselective manner through the one-pot double intramolecular haloetherification of σ-symmetric diene acetals, having (R,R)-hydrobenzoin as an acetal unit. The utility of the method was demonstrated by the short asymmetric synthesis of (+)-rubrenolide.

11 Fujita, Y.*1; Hamamoto, I.; Fujita, H.*2; Shimbara, Y.*1;
Adachi, T.*1; Berg, G.P.A.*2; Fujita, K.*2; Hatanaka, K.*2;
Kamiya, J.*2; Nakanishi, K.*2; Sakemi, Y.*2; Shimizu, Y.*2;
Uchida, M.; Wakasa, T.*2; Yosoi, M.
*1 (Graduate School of Science) *2 (Research Center for Nuclear Physics)
Evidence for the Existence of the [2 0 2]3/2 Deformed Band in Mirror Nuclei 25Mg and 25Al
Physical Review Letters, 92, 062502/1-4 (2004)

12 Hamaguchi, H.; Kosaka, S.; Ohno, H.; Tanaka, T.
(Graduate School of Pharmaceutical Sciences)
Bromoallenes as Allyl Dication Equivalents in the Absence of Palladium(0): Synthesis of Bicyclic Sulfamides by Tandem Cyclization of Bromoallenes
Angewandte Chemie International Edition, 44, 1513-1517 (2005)

Sulfamide is one of the most important structural motifs that exist in many pharmaceutically useful compounds. Based on our recent discovery that bromoallenes can act as allyl dication equivalents, we have developed a novel regio-selective synthesis of cyclic sulfamides containing a bicyclo[3.3.0]octane skeleton by palladium-free tandem cyclization of bromoallenes. The first intramolecular nucleophilic attack takes place at the central carbon atom of the allenic moiety, and is followed by a second intramolecular nucleophilic addition to afford the bicyclic sulfamide.

13 Inase, A.; Kodama, T.S.; Sharif, J.; Xu, Y.; Ayame, H.; Sugiyama, H.; Iwai, S.
(Graduate School of Engineering Science)
Binding of Distamycin A to UV-Damaged DNA
Journal of the American Chemical Society, 126, 11017-11023 (2004)

We have found that distamycin A, a natural antibiotic known as a minor groove binder, can bind to DNA duplexes containing the (6–4) photoproduct, one of the major UV lesions, despite the changes in both the chemical structure of the base moiety and the local tertiary structure of the DNA helix. Detailed analyses revealed that two distamycin molecules bound to the photoproduct-containing DNA even at a low drug concentration, whereas the 1:1 binding was observed for the undamaged DNA.

14 Kawasaki, S.*1; Zheng, G.-q.; Kan, H.*1; Kitaoka, Y.*1; Shishido, H.*2; Onuki, Y.*2
*1 (Graduate School of Engineering Science) *2 (Graduate School of Science)
Enhancing the Superconducting Transition Temperature of the Heavy Fermion Compound CeIrIn5 in the Absence of Spin Correlations
Physical Review Letters, 94, 037007/1-4 (2005)

15 Kawase, T.; Tanaka, K.; Shiono, N.; Seirai, Y.; Oda, M.
(Graduate School of Science)
Onion-Type Complexation Based on Carbon Nanorings and a Buckminsterfullerene
Angewandte Chemie International Edition, 43, 1722-1724 (2004)

16 Koga, A.; Kawakami, N.; Rice, T.M.; Sigrist, M.
(Graduate School of Engineering)
Orbital-selective Mott Transitions in the Degenerate Hubbard Model
Physical Review Letters, 92, 216402/1-4 (2004)

Mott metal-insulator transitions have been one of the most interesting subjects in condensed matter physics. We investigate the Mott transitions in two-band Hubbard models with different bandwidths. Applying dynamical mean field theory, we discuss the stability of itinerant quasi-particle states in each band. We demonstrate that separate Mott transitions occur at different Coulomb interaction strengths in general, which merge to a single transition only under special conditions. This kind of behavior may be relevant for some transition metal oxides.

17  Miyauchi, M.; Takashima, Y.; Yamaguchi, H.; Harada, A.
(Graduate School of Science)
Chiral Supramolecular Polymers Formed by Host-Guest Interactions
Journal of the American Chemical Society, 127, 2984-2989 (2005)

We have investigated for the first time the formation of cyclodextrin-based helical supramolecular polymers in an aqueous solution and in a solid state. The degree of polymerization of the supramolecular polymer was higher than 15. The formation of a left-handed helical supramolecular polymer was shown by the increasing intensities of Cotton effect peaks in circular dichroism spectra with the increase of the concentration of the chemically modified cyclodextrin. We could also achieve the visualization of the supramolecular polymers by STM.
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