107 research outputs found
Growth of quantum three-dimensional structure of InGaAs emitting at ~1 µm applicable for a broadband near-infrared light source
We obtained a high-intensity and broadband emission centered at ~1 µm from InGaAs quantum three-dimensional (3D) structures grown on a GaAs substrate using molecular beam epitaxy. An InGaAs thin layer grown on GaAs with a thickness close to the critical layer thickness is normally affected by strain as a result of the lattice mismatch and introduced misfit dislocations. However, under certain growth conditions for the In concentration and growth temperature, the growth mode of the InGaAs layer can be transformed from two-dimensional to 3D growth. We found the optimal conditions to obtain a broadband emission from 3D structures with a high intensity and controlled center wavelength at ~1 µm. This method offers an alternative approach for fabricating a broadband near-infrared light source for telecommunication and medical imaging systems such as for optical coherence tomography
Bone and Soft-Tissue Sarcoma: A New Target for Telomerase-Specific Oncolytic Virotherapy
Adenovirus serotype 5 (Ad5) is widely and frequently used as a virus vector in cancer gene therapy and oncolytic virotherapy. Oncolytic virotherapy is a novel antitumor treatment for inducing lytic cell death in tumor cells without affecting normal cells. Based on the Ad5 genome, we have generated three types of telomerase-specific replication-competent oncolytic adenoviruses: OBP-301 (Telomelysin), green fluorescent protein (GFP)-expressing OBP-401 (TelomeScan), and tumor suppressor p53-armed OBP-702. These viruses drive the expression of the adenoviral E1A and E1B genes under the control of the hTERT (human telomerase reverse transcriptase-encoding gene) promoter, providing tumor-specific virus replication. This review focuses on the therapeutic potential of three hTERT promoter-driven oncolytic adenoviruses against bone and soft-tissue sarcoma cells with telomerase activity. OBP-301 induces the antitumor effect in monotherapy or combination therapy with chemotherapeutic drugs via induction of autophagy and apoptosis. OBP-401 enables visualization of sarcoma cells within normal tissues by serving as a tumor-specific labeling reagent for fluorescence-guided surgery via induction of GFP expression. OBP-702 exhibits a profound antitumor effect in OBP-301-resistant sarcoma cells via activation of the p53 signaling pathway. Taken together, telomerase-specific oncolytic adenoviruses are promising antitumor reagents that are expected to provide novel therapeutic options for the treatment of bone and soft-tissue sarcomas
Superconductivity in oxygen-annealed FeTe1-xSx single crystal
We investigated the S-doping-driven phase transition from antiferromagnetic
to superconducting in FeTe1-xSx single crystals. The partial substitution of Te
by S suppresses antiferromagnetism in Fe-square lattice. Superconductivity is
induced by oxygen annealing for only FeTe1-xSx in which the long-range magnetic
ordering is suppressed. To realize superconductivity in FeTe1-xSx, both S
concentration enough to suppress antiferromagnetism and oxygen annealing are
required. Anisotropy of superconductivity in oxygen-annealed FeTe0.886S0.114
was estimated to be 1.17.Comment: 14 pages, 7 figure
Optical characterization of In-flushed InAs/GaAs quantum dots emitting a broadband spectrum with multiple peaks at ~1 μm
Dual-Matrix Domain-Wall: A Novel Technique for Generating Permutations by QUBO and Ising Models with Quadratic Sizes
The Ising model is defined by an objective function using a quadratic formula
of qubit variables. The problem of an Ising model aims to determine the qubit
values of the variables that minimize the objective function, and many
optimization problems can be reduced to this problem. In this paper, we focus
on optimization problems related to permutations, where the goal is to find the
optimal permutation out of the possible permutations of elements. To
represent these problems as Ising models, a commonly employed approach is to
use a kernel that utilizes one-hot encoding to find any one of the
permutations as the optimal solution. However, this kernel contains a large
number of quadratic terms and high absolute coefficient values. The main
contribution of this paper is the introduction of a novel permutation encoding
technique called dual-matrix domain-wall, which significantly reduces the
number of quadratic terms and the maximum absolute coefficient values in the
kernel. Surprisingly, our dual-matrix domain-wall encoding reduces the
quadratic term count and maximum absolute coefficient values from and
to and , respectively. We also demonstrate the
applicability of our encoding technique to partial permutations and Quadratic
Unconstrained Binary Optimization (QUBO) models. Furthermore, we discuss a
family of permutation problems that can be efficiently implemented using
Ising/QUBO models with our dual-matrix domain-wall encoding.Comment: 26 pages, 9 figure
Hadron resonances with coexistence of different natures
We discuss coexistence/mixing of different natures of hadronic composite
(molecule) and elementary (quark-intrinsic) ones in hadron resonances. The
discussions here are based on our previous publications on the origin of hadron
resonances \cite{Hyodo:2008xr}, exotic meson-nucleons as hadronic
composites containing one anti-heavy quark \cite{Yamaguchi:2011xb}, and the
study of as a typical example to show explicitly the mixing of the two
different natures \cite{Nagahiro:2011jn}. In all cases, interactions are
derived from the chiral dynamics of the light flavor sector. These interactions
generate in various cases hadronic composite/molecule states, serving varieties
of structure beyond the conventional quark model.Comment: Proceedings for Hadron Nuclear Physics (HNP) 2011, Pohang, Korea,
February 21-24 (2011
Growth of quantum three-dimensional structure of InGaAs emitting at ~1 µm applicable for a broadband near-infrared light source
We obtained a high-intensity and broadband emission centered at ~1 µm from InGaAs quantum three-dimensional (3D) structures grown on a GaAs substrate using molecular beam epitaxy. An InGaAs thin layer grown on GaAs with a thickness close to the critical layer thickness is normally affected by strain as a result of the lattice mismatch and introduced misfit dislocations. However, under certain growth conditions for the In concentration and growth temperature, the growth mode of the InGaAs layer can be transformed from two-dimensional to 3D growth. We found the optimal conditions to obtain a broadband emission from 3D structures with a high intensity and controlled center wavelength at ~1 µm. This method offers an alternative approach for fabricating a broadband near-infrared light source for telecommunication and medical imaging systems such as for optical coherence tomography
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