Quantum repeaters and computation by a single module

We present a protocol of remote nondestructive parity measurement (RNPM) on a pair of quantum memories. The protocol works as a single module for key operations such as entanglement generation, Bell measurement, parity check measurement, and an elementary gate for extending one-dimensional cluster states. The RNPM protocol is achieved by a simple combination of devices such as lasers, optical fibers, beam splitters, and photon detectors. Despite its simplicity, a quantum repeater composed of RNPM protocols is shown to have a communication time that scales sub-exponentially with the channel length, and it can be further equipped with entanglement distillation. With a reduction in the internal losses, the RNPM protocol can also be used for generating cluster states toward measurement-based quantum communication.Comment: 7 pages, 4 figure

Superlattice formation lifting degeneracy protected by non-symmorphic symmetry through a metal-insulator transition in RuAs

The single crystal of RuAs obtained by Bi-flux method shows obvious successive metal-insulator transitions at T_MI1~255 K and T_MI2~195$ K. The X-ray diffraction measurement reveals a formation of superlattice of 3x3x3 of the original unit cell below T_MI2, accompanied by a change of the crystal system from the orthorhombic structure to the monoclinic one. Simple dimerization of the Ru ions is nor seen in the ground state. The multiple As sites observed in nuclear quadrupole resonance (NQR) spectrum also demonstrate the formation of the superlattice in the ground state, which is clarified to be nonmagnetic. The divergence in 1/T_1 at T_MI1 shows that a symmetry lowering by the metal-insulator transition is accompanied by strong critical fluctuations of some degrees of freedom. Using the structural parameters in the insulating state, the first principle calculation reproduces successfully the reasonable size of nuclear quadrupole frequencies for the multiple As sites, ensuring the high validity of the structural parameters. The calculation also gives a remarkable suppression in the density of states (DOS) near the Fermi level, although the gap opening is insufficient. A coupled modulation of the calculated Ru d electron numbers and the crystal structure proposes a formation of charge density wave (CDW) in RuAs. Some lacking factors remain, but it shows that a lifting of degeneracy protected by the non-symmorphic symmetry through the superlattice formation is a key ingredient for the metal-insulator transition in RuAs.Comment: 10 pages, 10 figure

Metastatic carcinoma of the colon similar to Crohn's disease: a case report.

A 68-year-old Japanese man with a history of linitis plastica carcinoma of the stomach and subsequent gastrectomy 8 years previously presented with lower abdominal pain. Radiological and endoscopic examinations showed multiple submucosal nodular lesions similar to Crohn's disease in the ileocecal area. A firm diagnosis could not be made after initial multiple biopsies. Finally, a submucosal biopsy revealed adenocarcinoma. The ileocecal lesion was diagnosed as a recurrence because of the histological findings, which included mucosal preservation, a similarity with the histologic type of stomach carcinoma, and atypical immunoreactivity for primary colon carcinoma; the lesion was negative for both cytokeratin 7 and cytokeratin 20. In cases where metastatic carcinoma of the colon is suspected, we recommend early consideration of a submucosal biopsy.</p

A Method of Predicting Surface Condition of Concrete Structures : Prediction of corrosion of reinforcing bars and surface condition of concrete and revision of prediction based on concrete surface conditions

conference pape

Satisfactory mid- to long-term clinical and radiographic outcomes after surgical treatment of radial neck fracture in 10 children

Complications after surgical treatment of pediatric radial neck fractures are common. The purpose of this study was to evaluate the mid- to long-term clinical and radiographic outcomes after surgical treatment of pediatric radial neck fractures. We assessed 10 children who had been surgically treated for radial neck fractures. We mainly performed percutaneous intrafocal pinning to reduce the fracture; where this was inappropriate, we performed open reduction. Mid- to long-term clinical and radiographic outcomes were assessed, as well as whether these affected patient-related outcomes (Hand 20 questionnaire) at the final follow-up. Of the 10 patients (seven boys; mean age, 9 years; age range, 5–14 years; four fractures on the right-hand side, six on the left), four each were grades II and III, and two were grade IV, according to the Judet classification. The mean follow-up time was 6.7 (range, 3.6–11.2) years. Eight patients had restricted forearm pronation. The mean radial neck angulation on the fractured side was 36° (range, 5°–96°), preoperatively, and 2° (range, 0°–11°) at the final follow-up. There were eight cases of radial head overgrowth, three of premature physeal closure, two of notching of the radial neck, and one of heterotopic ossification. According to the Leung/Peterson Classification, four patients had “excellent,” three had “good,” and three had “fair” functionality. Eight patients had a perfect score upon completing the Hand 20 questionnaire. In conclusion, postsurgical patient-related outcomes for the 10 cases were satisfactory despite slightly restricted forearm range of motion and complications detected using radiography.departmental bulletin pape

Intrinsic anomalous Hall effect arising from antiferromagnetic structure revealed by high-quality NbMnP

The large anomalous Hall effect (AHE) in antiferromagnetic (AF) materials arises from symmetry breaking equivalent to a ferromagnetic (FM) state. Consequently, this suggests that the observed AHE is induced by the intrinsic mechanism of the band structure effect, which in turn induces dissipationless transverse conductivity. Confirmation of impurity-insensitive anomalous Hall conductivity (AHC) is crucial to conclude this interpretation; however, experimental investigations in AF materials are limited by the lack of high quality systems. In this study, we show that the AF material NbMnP, which exhibits a large AHE, offers a high quality single crystal. Our findings clearly revealed that the large AHC and the tiny net magnetization of $\sim10^{-3} \mu_{\mathrm{B}}$/Mn are inherent in this material, irrespective of disorder. NbMnP is a novel AF material that generates FM responses in the regime where there is less impurity scattering.Comment: 11 pages, 4 figure

Maternal exposure to nanoparticulate titanium dioxide during the prenatal period alters gene expression related to brain development in the mouse

<p>Abstract</p> <p>Background</p> <p>Nanotechnology is developing rapidly throughout the world and the production of novel man-made nanoparticles is increasing, it is therefore of concern that nanomaterials have the potential to affect human health. The purpose of this study was to investigate the effects of maternal exposure to nano-sized anatase titanium dioxide (TiO₂) on gene expression in the brain during the developmental period using cDNA microarray analysis combined with Gene Ontology (GO) and Medical Subject Headings (MeSH) terms information.</p> <p>Results</p> <p>Analysis of gene expression using GO terms indicated that expression levels of genes associated with apoptosis were altered in the brain of newborn pups, and those associated with brain development were altered in early age. The genes associated with response to oxidative stress were changed in the brains of 2 and 3 weeks old mice. Changes of the expression of genes associated with neurotransmitters and psychiatric diseases were found using MeSH terms.</p> <p>Conclusion</p> <p>Maternal exposure of mice to TiO₂nanoparticles may affect the expression of genes related to the development and function of the central nervous system.</p

Behavioral Cost-Based Recommendation Model for Wanderers in Town

Abstract. This paper proposes a new model for recommendation based on the behavioral cost of recommendees in town. The model is based on cost-benefit analysis of the information provided to the user, referring to the model of temporal discounting and preference reversal. Here we assume that behavioral cost may be regarded as time in temporal discounting. A recommender system based on this model can select information, which is located in the surrounding area (not so far away) and may be preferred by the user, if the system can estimate where the reversal phenomenon may occur. The experiments were made using an experimental social service, called &quot;pin@clip&quot;, which is an iPhone-based social bookmarking service in Shibuya, Tokyo, Japan that has been operating since December 2009. The experimental results show that the phenomenon of preference reversals might occur, even though the authors could not obtain statistically significant data