This contribution explores the relation between molecular second hyperpolarizabilities (gamma) and molecular architecture in phenylacetylene dendrimers using the semiempirical molecular orbital method, that is, INDO/S method. The orientationally averaged gamma of a large-size phenylacetylene dendrimer, which is composed of 24 units of phenylacetylenes and is referred to as D25, is found to be about 50 times as large as that of the diphenylacetylene monomer. In contrast, the gamma(s)() value of D25 is found to be about 6 times as small as that of the para-substituted phenylacetylene oligomer (L25) composed of 24 units of phenylacetylenes. To investigate the structure-property relation in gamma for D25 and L25, we examine the spatial contributions of electrons to gamma values using gamma density analysis. The present analysis reveals that the dominant contributions of electrons to gamma of D25 are localized in the linear-leg regions parallel to the applied electric field and the contributions are also well segmented at the meta-connected points (benzene rings), while the spatial distribution of the gamma density of L25 is extended over the whole region of the chain, and the dominant contribution stems from the both-end regions. It is found for D25 that the magnitude of contributions to gamma in the internal region is more enhanced than that in the outer region. We further found that the magnitudes of contributions in internal linear-leg regions of D25 are somewhat larger than those of the same-size isolated linear-leg molecules. This suggests that the slightly remaining pi-conjugations via the meta-branching points still enhance the contributions to gamma localized in the linear-leg regions. These features of spatial contributions to gamma of D25 are found to originate in the fractal architecture, in which pi-conjugation lengths in the linear-leg region increase on going from the periphery to the core. Finally, fractal antenna dendrimers are expected to be promising novel nonlinear optical (NLO) substances with a controllability of the magnitude and spatial contribution of the third-order NLO properties.

Discoveries of superconductivity of MgB 2 by Akimitsu et al. and high-T c cupurate superconductors by Bednorz and Muller have raised great interest for elucidation of the superconducting mechanism from both experimental and theoretical grounds. The transition temperature (T c ) was found to be 40 K for MgB 2 , while the very high-T c over 130 K was reported for doped copper oxides with layer structures. A crucial role of the electron-phonon (EP) interaction was pointed out as a common mechanism of the superconductivity of both materials. However, such high-T c superconductivity may indicate the possibility of cooperative mechanism of the EP interaction with others such as electron correlation (EC) and multiband (MB) effects discussed in part I (Int J Quantum Chem 1990, 37, 167) of this series. Here, as a continuation of part I, theoretical backgrounds are briefly described to select active orbital space for superconductivity and elucidate the nature of EP, EC, and MB effects for cooperative mechanisms. Next, molecular orbital calculations of Mg m B n and cagetype carbon cluster are carried out to elucidate contributions of the EP interaction using McMillan equation. The relative contributions of the EP and EC interactions are also discussed in relation to the screening of the Coulomb repulsion. Pair binding energies are calculated for cage-type carbon clusters. Finally, the cooperative mechanisms of the EP, EC, and MB effects are discussed to realize the high-T c superconductivity in molecule-based materials such as cage compounds and nanotubes. Several possible candidates are proposed on both experimental and theoretical grounds.

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We retrospectively evaluated the outcomes of 37 adult patients with acute lymphoblastic leukemia (ALL) undergoing allogeneic hematopoietic stem cell transplantation (allo-SCT) conditioned with medium-dose VP-16 (VP, 30 mg/kg), cyclophosphamide (CY, 120 mg/kg), and fractionated total-body irradiation (TBI, 12 Gy) (medium-dose VP/CY/TBI). The median age of the patients was 26 years. Thirteen patients underwent transplantation from HLA-matched related donors (MRD), 18 patients underwent transplantation from HLA-matched unrelated donors (MUD), and 6 patients underwent transplantation from HLA-mismatched donors (MMD). Thirty-two patients received bone marrow and 4 patients received peripheral blood stem cells. Ten patients were Philadelphia chromosome-positive (Ph(+)) and 35 patients were in complete remission (CR) at transplantation. All of the patients achieved engraftment, and grade 3 organ toxicity before engraftment occurred in 27 patients. Grade II-III acute graft-versus-host disease (GVHD) and chronic GVHD (cGVHD) occurred in 15 and 18 patients, respectively. No patient developed grade IV acute GVHD (aGVHD) or died of GVHD. At median follow-up of 35.1 months, 32 patients were alive and all Ph(+) patients were alive. Three patients died of relapse and 2 died of transplant-related mortality (TRM). The actuarial 3-year overall survival (OS) rate, relapse rate, and TRM rate were 89.2%, 8.1%, and 5.4%, respectively. Non-CR at transplantation, MRD, and no aGVHD were significant adverse prognostic factors for survival. Medium-dose VP/CY/TBI for adult ALL patients was associated with lower relapse rate and no increase in toxicity, resulting in better survival.