965 research outputs found
Oscillations in the G-type Giants
The precise radial-velocity measurements of 4 G-type giants, 11Com,
Hya, Tau, and Her were carried out. The short-term variations
with amplitudes, 1-7m/s and periods, 3-10 hours were detected. A period
analysis shows that the individual power distribution is in a Gaussian shape
and their peak frequencies () are in a good agreement with the
prediction by the scaling law. With using a pre-whitening procedure,
significant frequency peaks more than 3 are extracted for these
giants. From these peaks, we determined the large frequency separation by
constructing highest peak distribution of collapsed power spectrum, which is
also in good agreement with what the scaling law for the large separation
predicts. Echelle diagrams of oscillation frequency were created based on the
extracted large separations, which is very useful to clarify the properties of
oscillation modes. In these echelle diagrams, odd-even mode sequences are
clearly seen. Therefore, it is certain that in these G-type giants, non-radial
modes are detected in addition to radial mode. As a consequence, these
properties of oscillation modes are shown to follow what Dzymbowski et
al.(2001) and Dupret et al.(2009) theoretically predicted. Damping times for
these giants were estimated with the same method as that developed by Stello et
al.(2004). The relation of Q value (ratio of damping time to period) to the
period was discussed by adding the data of the other stars ranging from dwarfs
to giants.Comment: 28 pages, 16 figures, accepted for publication in PASJ 62, No.4, 201
Earthquake Resistance of New Type Viaduct Structure
An experiment and a numerical analysis were carried out in order to examine the earthquake resistance of a new type viaduct structure. The experiment was a dynamic centrifuge modeling which used the viaduct model of the rates 1/50 of a scale. The 3-dimensional finite element analysis was performed in order to confirm the results of the dynamic centrifuge modeling. At the results, new knowledge was obtained with regard to the viaduct structure
Correlation between transition temperature, in-plane copper-oxygen bond length, and tilt/buckling of the CuO2 plane in cuprate superconductors
Correlation among transition temperature, in-plane Cu-O bond length, and tilt/buckling in cuprate superconductors were examined in detail. As for cuprates with a single CuO_2 layer, tilt structure was observed in the region, whose in-plane Cu-O length was 1.906-1.926 Å, and that the tilt structure drastically suppressed superconductivity. As for cuprates with double CuO_2 layers, all the compounds had buckling distortion in a CuO_5 pyramid. The degree of distortion was determined only by a kind of cation between the two facing CuO_5 pyramids, that is, calcium or yttrium. A higher transition temperature was obtained for a copper oxide with having larger Cu-O length and smaller buckling degree. A common feature of layered cuprates was the existence of three major classes distinguished by the cations Ba^, Sr^, and Ln^ occupying the 9-coordination sites
Service Chain Provisioning Model Considering Traffic Changes Due to Virtualized Network Functions
Service chaining provides network services by flexibly configuring service chains that connect virtualized network functions (VNFs) in the appropriate order so as to satisfy users’ needs. Existing models can be inefficient in terms of consuming network and computation resources since the models do not consider the traffic changes due to VNFs or the models restrict routing and VNF placement. This paper proposes a service chain provisioning model that handles the traffic changes created by VNFs while determining the VNF visit order of each request, request routes, and VNF placement. The service chain provisioning problem is formulated as an integer linear programming (ILP) problem. Three methods for limiting the number of VNF visit order patterns considered in the ILP problem are introduced to shorten the computation time. In order to handle a problem that is intractable with the ILP model, we introduce a greedy algorithm and an algorithm that divides the problem into the VNF placement part and the routing part. Numerical results show that considering the traffic changes due to VNFs yields more efficient consumption of network and computation resources than the alternative of assuming that the traffic amount of each request is constant between the endpoints. The results also show that the computation time can be shortened in our examined scenarios while we obtain the objective value larger by at most 0.4% than the optimal value by limiting the number of visit order patterns considered
An Endogenous Murine Leukemia Viral Genome Contaminant in a Commercial RT-PCR Kit is Amplified Using Standard Primers for XMRV
During pilot studies to investigate the presence of viral RNA of xenotropic murine leukemia virus (MLV)-related virus (XMRV) infection in sera from chronic fatigue syndrome (CFS) patients in Japan, a positive band was frequently detected at the expected product size in negative control samples when detecting a partial gag region of XMRV using a one-step RT-PCR kit. We suspected that the kit itself might have been contaminated with small traces of endogenous MLV genome or XMRV and attempted to evaluate the quality of the kit in two independent laboratories. We purchased four one-step RT-PCR kits from Invitrogen, TaKaRa, Promega and QIAGEN in Japan. To amplify the partial gag gene of XMRV or other MLV-related viruses, primer sets (419F and 1154R, and GAG-I-F and GAG-I-R) which have been widely used in XMRV studies were employed. The nucleotide sequences of the amplicons were determined and compared with deposited sequences of a polytropic endogenous MLV (PmERV), XMRV and endogenous MLV-related viruses derived from CFS patients. We found that the enzyme mixtures of the one-step RT-PCR kit from Invitrogen were contaminated with RNA derived from PmERV. The nucleotide sequence of a partial gag region of the contaminant amplified by RT-PCR was nearly identical (99.4% identity) to a PmERV on chromosome 7 and highly similar (96.9 to 97.6%) to recently identified MLV-like viruses derived from CFS patients. We also determined the nucleotide sequence of a partial env region of the contaminant and found that it was almost identical (99.6%) to the PmERV. In the investigation of XMRV infection in patients of CFS and prostate cancer, researchers should prudently evaluate the test kits for the presence of endogenous MLV as well as XMRV genomes prior to PCR and RT-PCR tests
Cooperative Step Climbing Using Connected Wheeled Robots and Evaluation of Remote Operability
The present study evaluates the remote operability of step climbing using two connected robots that are teleoperated by individual operators. In general, a teleoperated robot is manipulated by an operator who is viewing moving images from a camera, which is one of the greatest advantages of such a system. However, robot teleoperation is not easy when a teleoperated robot is affected by the force from another robot or object. We constructed a step climbing system using two connected teleoperated robots. A theoretical analysis and the results of simulations clarified the correlations among the robot velocity, the manipulation time of the robots, and the height of the front wheels when climbing a step. The experimental results demonstrate the step climbing ability of the teleoperated robot system
A case report of acute dermatitis that developed during an experiment examining the bromination of 3-hexylthiophene
Occupational cases with allergic reaction to fragrance substances, which refer to various chemicals providing aroma characteristics, are arising with its recent usage diversification from pharmaceutical, perfume industry to aromatic remedies. However, chemicals responsible for fragrance allergy have hardly been identified because its component is complex and its sensitization is not frequent. This report will present a case of acute allergic dermatitis that is likely induced by 3-hexylthiophene, one of aromatic compounds often contained in fragrance substances. The case, who was a 27-year male researcher engaged in organic chemical synthesis for six years, was exposed to 3-hexylthiophene and its product (2-bromo-3-hexylthiophene) through an experiment in May 2004 and itching, swelling and eczema immediately developed from face to back. This case of sensitization to 3-hexylthiophene suggests that it be a possible allergen for fragrance allergy
Associations between social fragmentation, socioeconomic deprivation and suicide risk across 1887 municipalities in Japan, 2009-2017 : a spatial analysis using the Bayesian hierarchical model
Funding This work was supported by a Grant-in-Aid for scientific research from the Ministry of Education, Culture, Sports, Science and Technology of Japan (Award Number 18K10080).Peer reviewedPublisher PD
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