Adaptive expectations and dynamic adjustment in noncooperative games with incomplete information

This paper is concerned with the analysis of a Nash equilibrium of a noncooperative game. It can be shown that, without complete information about the other players' objectives or interests, the group of players, as a whole, can reach a Nash equilibrium by adopting a class of adaptive expectation and dynamic adjustment processes. It is shown that, if the expectation and adjustment processes are made continuously, the stability of the overall dynamic process is independent of the specific mechanisms of the expectation and the adjustment, but depends on the properties of each player's objective or payoff function. If, however, expectation and adjustment processes are made at discrete time intervals, the stability of the discrete process depends on the speed of adjustment chosen by each player.This research was supported by ONR Contract No. N00014-75-C-0738. The authors are indebted to the referee for several valuable comments and suggestions for improvement.     

Oxygen isotope effect in optimally doped Bi2Sr2CaCu2O8+δ studied by low-energy ARPES

Using angle-resolved photoemission spectroscopy (ARPES) with low-energy tunable photons, we studied the oxygen isotope effect in optimally doped Bi₂Sr₂CaCu₂O_8+δ (Bi2212). We found the oxygen isotope shift in the real part of the electron self-energies [ReΣ(ω)s] along the nodal direction derived not only from the momentum distribution curves (MDCs) but also from the energy distribution curves (EDCs). Present results indicate straightforwardly the coupling between the nodal electrons and the phonons.     

Interplay among Coulomb interaction, spin-orbit interaction, and multiple electron-boson interactions in Sr2RuO4

Using polarization- and hν-dependent angle-resolved photoemission spectroscopy, we uncovered the fine details of a quasiparticle's dynamics of a typical multiband superconductor, Sr2RuO4. We found strong hybridization between the in-plane and out-of-plane quasiparticles via the Coulomb and spin-orbit interactions. This effect enhances the quasiparticle mass due to the inflow of out-of-plane quasiparticles into the two-dimensional Fermi surface sheet, where the quasiparticles are further subjected to the multiple electron-boson interactions. We suggest that the spin-triplet p-wave superconductivity of Sr2RuO4 is phonon mediated.     

Co-induced nano-structures on Si(1 1 1) surface

The interaction of cobalt atoms with silicon (1 1 1) surface has been investigated by means of scanning tunneling microscopy (STM) and low-energy electron diffraction (LEED). Besides the Co silicide islands, we have successfully distinguished two inequivalent Co-induced reconstructions on Si(1 1 1) surface. Our high-resolution STM images provide some structural properties of the two different derived phases. Both of the two phases seem to form islands with single domain. The new findings will help us to understand the early stage of Co silicide formations.     

A self-contained polymeric 2-DE chip system for rapid and easy analysis

We developed a polymeric 2-DE chip system. The chip consisted of an IEF region, an SDS-PAGE region, a valveless connection port, and a sample introduction port. A "junction structure" as a valveless connection port, which allowed separating and connecting the first- and second-dimensional gels, was fabricated between their regions. A "solution inlet" as a sample introduction port was fabricated to perform the liquid and sample introductions without solution leakage. Simultaneous sample monitoring was performed using the on-chip detection system. The performances of the system were demonstrated using commercially available proteins as a standard specimen and tissue-extracted proteins as the real samples. All procedures were employed without any movement of relocation part. This new 2-D separation system realized improved labor-intensive operations and a reduced experimental time.     

Spin-polarized Dirac-cone-like surface state with d character at W(110)

The surface of W(110) exhibits a Dirac-cone-like state with d character within a spin-orbit-induced symmetry gap. As a function of the wave vector parallel to the surface, it shows a nearly massless energy dispersion and a pronounced spin polarization, which is antisymmetric with respect to the Brillouin zone center. In addition, the observed constant energy contours are strongly anisotropic for all energies. This discovery opens new pathways to the study of surface spin-density waves arising from a strong Fermi surface nesting as well as d-electron-based topological properties.     

Temperature dependent quantum well state on Cu(1 1 0)(2 × 1) striped surface studied by angle resolved photoelectron spectroscopy

We have investigated the temperature dependence of angle resolved photoelectron spectroscopy for the lateral quantum well states (QWS) on the striped Cu(1 1 0)(2 × 1)O surface. For the striped surface with oxygen coverage of 0.25 ML, we have successfully observed two discrete levels along a perpendicular direction to the stripes in the surface Brillouin zone, which is generated by quantization of the Shockley surface state. We have found that the relative photoelectron intensity of the two discrete levels depends on the temperature. The photoelectron intensity tends to concentrate on the ground level of the QWS with decreasing temperature. Our investigation indicates that the electron population of each quantum well level depends on the temperature.     

Total syntheses of (+)-chloropuupehenone and (+)-chloropuupehenol and their analogues and evaluation of their bioactivities

Tetracyclic pyrans (+)-chloropuupehenone (1) and (+)-chloropuupehenol (5) and its C8-R-isomer (+)-3 were synthesized via a one-pot condensation of 1-chloro-2-lithio-3,5,6-tris(tert-butyldimethylsilyloxy)benzene (8) with (4aS,8aS)-3,4,4a,5,6,7,8,8a-octahydro-2,5,5,8a-tetramethylnaphthalene-1-carboxaldehyde (7). The major condensation product, (4aS,6aR,12bS)-2H-9,10-bis(tert-butyldimethylsilyloxy)-11-chloro-1,3,4,4a,5,6,6a,12b-octahydro-4,4,6a,12b-tetramethyl-benzo[a]xanthene (4), after desilylation provided tetracyclic pyran (+)-(4aS,6aR,12bS)-2H-11-chloro-1,3,4,4a,5,6,6a,12b-octahydro-4,4,6a,12b-tetramethyl-benzo[a]xanthene-9,10-diol (3). At a dosage of 42 mg/rat over 8 h, pyran diol 3 inhibited the intestinal absorption of cholesterol by 71% in rats. Tetracyclic pyran 4 was also converted to o-quinone 28, which inhibited cholesteryl ester transfer protein (CETP) activity and L1210 leukemic cell viability with IC(50) values of 31 and 2.4 microM, respectively. Diol (+)-5 inhibited CETP activity with an IC(50) value of 16 microM. The minor condensation product, (4aS,6aS,12bS)-2H-9,10-bis(tert-butyldimethylsilyloxy)-11-chloro-1,3,4,4a,5,6,6a,12b-octahydro-4,4,6a,12b-tetramethyl-benzo[a]xanthene (6), was transformed into (+)-5 and (+)-1. A stepwise stereoselective synthesis of (+)-1 was also developed utilizing an oxyselenylation ring-closure reaction. The synthetic sequence also produced four biologically active naturally occurring drimanic sesquiterpenes, (+)-drimane-8alpha,11-diol (34), (-)-drimenol (38), (+)-albicanol (39), and (-)-albicanal (31) as intermediates.