Spin-Polarization Response Functions in High-Energy (e,e'p) Reactions

Spin-polarization response functions are examined for high-energy $(\vec{e},e'\vec{p})$ reaction by computing the full 18 response functions for the proton kinetic energy $T_{p'}=$ 0.515 GeV and 3.179 GeV with an 16O target. The Dirac eikonal formalism is applied to account for the final-state interactions. The formalism is found to yield the response functions in good agreement with those calculated by the partial-wave expansion method at 0.515 GeV. We identify the response functions that depend on the spin-orbital potential in the final-state interactions, but not on the central potential. Dependence on the Dirac- or Pauli-type current of the nucleon is investigated in the helicity-dependent response functions, and the normal-component polarization of the knocked-out proton, $P_n$, is computed.Comment: 22 pages, Latex, figures available at ftp://ftp.krl.caltech.edu/pub/users/rseki/it

Enhancement of the Gilbert damping constant due to spin pumping in noncollinear ferromagnet/nonmagnet/ferromagnet trilayer systems

We analyzed the enhancement of the Gilbert damping constant due to spin pumping in non-collinear ferromagnet / non-magnet / ferromagnet trilayer systems. We show that the Gilbert damping constant depends both on the precession angle of the magnetization of the free layer and on the direction of the magntization of the fixed layer. We find the condition to be satisfied to realize strong enhancement of the Gilbert damping constant.Comment: 4 pages, 3 figures, to be published in Phys. Rev.

Symmetry of `molecular' configurations of interacting electrons in a quantum dot in strong magnetic fields

A molecular description for magic-number configurations of interacting electrons in a quantum dot in high magnetic fields developed by one of the authors has been elaborated for four, five and six electron dots. For four electrons, the magic spin-singlet states are found to alternate between two different resonating valence bond (RVB)-like states. For the five-electron spin-polarized case, the molecular description is shown to work for the known phenomenon of magic-number sequences that correspond to both the N-fold symmetric ring configuration and a $(N-1)$-fold symmetric one with a center electron. A six-electron dot is shown here to have an additional feature in which inclusion of quantum mechanical mixing between classical configurations, which are deformed and degenerate, restores the N-fold symmetry and reproduces the ground-state energy accurately.Comment: 4 pages, to be published in Physisca

Immunostimulation-Mediated Anti-tumor Activity of Bamboo (Sasa senanensis) Leaf Extracts Obtained Under ‘Vigorous’ Condition

Traditional Japanese medicine uses the leaves of Kumaizasa bamboo extracted in hot water at 100°C. For this study, we developed a new, ‘vigorous’ extraction method involving steps at 100, 121 and 196°C. This procedure not only yielded greater amounts of extract but also with significant increase in immunostimulating activity, which induces activation of human natural killer (NK) cells, macrophages and potent induction of IL-2, IL-12 and IFN-γ in tumor bearing mice. The efficacy of the extract to facilitate phagocytosis and nitric oxide production by mouse peritoneal macrophages was determined and compared with that of 1,3-β-glucan. Anti-tumor activity was evaluated in vivo in several mouse tumor models (S-180, C38 and Meth-A). Oral administration of the extracts was carried out when tumor reached size of approximately 6 mm at concentrations of 0.05% or higher. The extracts significantly suppressed tumor growth in S-180 and C38 tumor models. Overall survival was significantly prolonged in the treatment group than that of control. Activation of macrophages and NK cells by the extracts suggests that the anti-tumor efficacy of the extract is mediated by immunopotentiation. The extracts resolved into three major fractions (F-I, F-II and F-III) in Sephadex gel chromatography. Fraction F-I consists of 1,3-β-glucan and stimulated both macrophages and NK cells suggesting that it may be the primary immunopotentiating factor in suppressing cancer. Fraction F-III has potent free radical scavenging effects and may play an important role in cancer prevention. These results warrant further translation and clinical investigations

Lifecycle management of orphan drugs approved in Japan

[Background] The development of orphan drugs (ODs) is challenging from both development and business perspectives because of their small patient populations. To overcome such business challenges, lifecycle management (LCM), which maximizes profits by increasing sales and extending product lifetimes, is important to overcome the business challenges arising from their small patient populations. To clarify the activities of the LCM of ODs, we investigated additional indications that contribute to market expansion and marketing exclusivity using the patent extension and re-examination system of ODs approved in Japan between 2004 and 2019. [Results] The 203 ODs consisting of 173 active ingredients were approved in Japan between 2004 and 2019. Sixty-eight (39%) of the 173 active ingredients have additional indications, of which 57 have at least one non-OD indication. Three-fourths of the 203 ODs had patent rights, and most of them included substance or use claims. Although the re-examination period for most ODs was 10 years after the approval, most patents had a longer duration than the re-examination period. [Conclusions] Pharmaceutical companies were actively adding non-OD indications and were emphasizing the use of patent rights by registering extensions of substance or use patents for exclusive marketing periods. These results indicate that LCM through the addition of indications and registration of patent extensions is carried out as a strategy for many ODs in Japan, similar to the LCM of general non-ODs