Search Results - (Author, Cooperation:S. Shibata)

2018-04-18

American Physical Society (APS)

0556-2821

1089-4918

Physics

Experiments in gravity, cosmology, cosmic rays

2013-05-07

Nature Publishing Group (NPG)

0028-0836

1476-4687

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

Animals ; *Bone Remodeling ; Bone and Bones/anatomy & histology/*innervation/*metabolism ; Cell Differentiation ; Cells, Cultured ; Female ; Male ; Mice ; Organ Size ; Osteoblasts/cytology/metabolism ; Semaphorin-3A/deficiency/genetics/*metabolism ; Sensory Receptor Cells/cytology/*metabolism

2018-07-10

American Physical Society (APS)

0556-2821

1089-4918

Physics

Experiments in gravity, cosmology, cosmic rays

1089-7550

AIP Digital Archive

Physics

There has been limited work on the effects of alloying elements on the properties of hot-worked anisotropic magnets. The coercivity mechanisms for sintered and rapidly solidified Nd-Fe-B magnets are different, and additives can have different effects on magnetic properties. The present study was conducted to clarify the effects of various alloying elements on the properties of hot-worked magnets. Ribbons of composition (Nd13.6−xRx)(Fe77.6−yTyCo2.8)B6.0 (R=Ce and Dy; T=Al, V, Cu, Ga, Zr, Nb, Mo, and Sn; x=0, 1, and 2; y=0, 0.5, and 1.0) were prepared by melt spinning. Anisotropic magnets were made at 1073 K with 55.6% reduction in height by die upsetting. Room-temperature magnetic properties and irreversible losses after exposure at 323–473 K were determined. The results showed that small amounts of Al, V, Cu, and Ga enhanced the remanence of the magnets, while Dy, Al, Ga, Zr, Nb, and Mo improved the coercivity. Dy, Ga, and Mo additions were effective in increasing the heat resistance temperature (HRT), defined as the temperature where the irreversible loss is 3%. HRT is dependent on initial intrinsic coercivity and the squareness ratio (Hk/iHc) of the demagnetization curve. An equation relating these parameters is given. An HRT of 453 K was obtained with a suitable alloy composition.

Electronic Resource

1089-7550

AIP Digital Archive

Physics

Anisotropic Nd-Fe-B magnets are produced from melt-spun ribbons by hot working technique. The processing is facilitated by improved workability. In order to obtain a sound magnet, it is important to suppress the crack initiation and growth. An investigation was carried out to study the deformation mechanism of the alloy system and to improve workability by changes in alloy composition. Alloy ribbons with composition (Nd13.6−xRx) (Fe77.6−y Ty Co2.8)B6.0 [R=Ce, Dy; T=Al, Si, V, Cu, Ga, Zr, Nb, Mo, Sn; x= 0, 1, 2; y=0, 0.5, 1.0] were prepared by melt spinning and then hot pressed into fully dense compacts. These compacts were upset in a hot working simulator. Hot workability was evaluated by measuring the crack opening displacement on the surface at the half height of the upset specimen. The relationship between strain rate and flow stress was found to be expressed by the equation: ε(overdot) = Aσn exp( − Q/RT). Values of n and Q were obtained for quarternary composition (Nd-Fe-Co-B). The effects of strain and strain rate on magnetic properties were also studied for quarternary composition. Of the additive elements, cerium and silicon addition showed significant improvement in workability without loss of coercivity.

Electronic Resource

1089-7550

AIP Digital Archive

Physics

We have measured the photocurrent-electric field (Jph-F) characteristics of slightly boron (B) doped (0≤[B2H6]/[SiH4]≤10 ppm) amorphous silicon (a-Si:H) Schottky photodiodes with a configuration of Cr/a-Si:H/ITO. The measurements were performed with different bias directions and two light wavelengths (555 and 660 nm), and mobility-lifetime (μτ) products were deduced by two methods. One is by fitting the experimental plots to the theoretical curves developed by Crandall [Semiconductors and Semimetals (Academic, Orlando, FL, 1984), Vol. 21, Pt. B, p. 245.]. The other is a new one we have proposed where the transition electric field Ftr, at which Jph changes from space-charge-limited current to the theoretical curve given by Crandall, is applied to the relationship μτFtr=L, where L is the thickness of a-Si:H. It was found that the former method is applicable only where a-Si:H is homogeneously illuminated and no space charge is formed. On the other hand, the latter method is effective where a-Si:H is inhomogeneously illuminated and a space charge is formed in the carrier transit region. The μhτh deduced by the latter method increased from 2×10−9 to 3×10−8 cm2/V when the B-doping ratio was increased from 0 to 3 ppm, but remained nearly constant with further doping. In contrast, μeτe monotonically decreased from 2×10−8 to 2×10−9 cm2/V with increased doping. The (μτ)fit deduced by the former method coincides with the μhτh at doping ratios higher than 3 ppm, but did not at lower doping ratios probably because of a space-charge formation by deep hole trapping and incomplete homogeneous illumination. These changes in μτ are discussed microscopically in terms of the charge state of the dangling bond state.

Electronic Resource

1365-2044

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Electronic Resource

1365-3083

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Human monoclonal anti-single/double-stranded (ss/ds) DNA anlibodies (NE-1 and NE-13) expressed cross-reactive idiotypes (Id), NE-1 Id, which have been delected on the lupus glomeruli-deposited anti-DNA antibodies. The nucleotide sequences of the variable regions of NE-1 and NE-13 clones were analogous except for one nucleotide difference in the Vk region. The VH and Vk gene segments of NE-13 clone were identical with germline genes VH4.21 and Vb(or Vb′). respectively. CDR3sof NE-l and NE-13 heavy chains were arginine rich and CDR1s contained an amino acid stretch. SGYY, the inverted sequence of YYGS. which was shared among CDR3s of several anti-DNA antibodies. Clonal frequency analysis using a limiting dilution method revealed that NE-1 Id-positive clones at precursor cell level increased in lupus patients. These findings suggest that some IgM anti-DNA clones which express NE-1 Id associated with lupus nephritis use germline genes without mutation and they may be preferentially expanded at the precursor cell levels as well as at the mature cell level.

Electronic Resource

1365-3040

Blackwell Publishing Journal Backfiles 1879-2005

Biology

A combined model to simulate CO2 and H2O gas exchange at the leaf scale was parameterized using data obtained from in situ leaf-scale observations of diurnal and seasonal changes in the CO2 and H2O gas exchange of four temperate deciduous broad-leaved trees using a porometric method. The model consists of a Ball et al. type stomatal conductance submodel [Ball, Woodrow & Berry, pp. 221–224 in Progress in Photosynthesis Research (ed. I. Biggins), Martinus-Nijhoff Publishers, Dordrecht, The Netherlands, 1987] and a Farquhar et al. type biochemical submodel of photosynthesis (Farquhar, von Caemmerer & Berry, Planta 149, 78–90, 1980). In these submodels, several parameters were optimized for each tree species as representative of the quantitative characteristics related to gas exchange. The results show that the seasonal physiological changes of Vcmax25 in the biochemical model of photosynthesis should be used to estimate the long-term CO2 gas exchange. For Rd25 in the biochemical model of photosynthesis and m in the Ball et al. type stomatal conductance model, the difference should be counted during the leaf expansion period.

Electronic Resource

0020-1693

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

0003-2670

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

1365-2133

Blackwell Publishing Journal Backfiles 1879-2005

Medicine

Background  Bowen's disease in the genital area is generally considered to be caused by mucosal high-risk human papillomaviruses (HPVs). However, the detection rate and spectrum of HPVs in extragenital Bowen's disease are various and it is not clear to what extent HPV is involved in its pathogenesis.Objectives  To assess the degree of association of HPV in extragenital cases by examining detection rates, types, quantities and localization of HPV.Methods  A polymerase chain reaction (PCR) approach that we had previously established, which can give sensitive detection of a broad range of HPVs from cutaneous [including epidermodysplasia verruciformis-related HPVs (EV-HPVs)] to mucosal HPVs, was applied to samples from 41 patients with extragenital Bowen's disease and normal skin samples from 48 individuals. Semiquantitative L1-PCR and tyramide-based in situ hybridization (ISH) were also employed for positive cases.Results  HPVs belonging to the mucosal high-risk group were detected in three patients with Bowen's disease (7%; two HPV 16 and one HPV 33), with 101−103 copy equivalents per diploid amount of cellular DNA. They were distributed among most nuclei of tumour cells but in none of the cells of adjacent normal skin. HPVs belonging to the cutaneous group were detected in two patients (5%; HPV 27 and HPV 76) at 10−2−10−3 copy equivalents, the same level as in a normal skin specimen positive for type 23 EV-HPV. No positive signals were observed by ISH.Conclusions  HPVs belonging to the mucosal high-risk group may participate in the development of extragenital Bowen's disease.

Electronic Resource

0304-4165

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Medicine

Physics

Electronic Resource

0005-2760

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Medicine

Physics

Electronic Resource

0006-291X

[abr] IL-1; interleukin-1 ; [abr] PGI"2; prostacyclin ; [abr] TNF; tumor necrosis factor

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Physics

Electronic Resource

0003-9861

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Physics

Electronic Resource

0003-9861

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Biology

Chemistry and Pharmacology

Physics

Electronic Resource

1476-4687

Nature Archives 1869 - 2009

Biology

Chemistry and Pharmacology

Medicine

Natural Sciences in General

Physics

[Auszug] As part of an extensive screening programme for abnormal haemoglobins in Japanese individuals, some two thousand patients who visited the Yamaguchi Prfectoral Central Hospital in Hofu City, Yamaguchi Prefecture, have been tested by agar gel electrophoresis (pH. 7-0 and 8-6)1 since 1964. An abnormal ...

Electronic Resource

0368-1874

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource

0368-1874

Elsevier Journal Backfiles on ScienceDirect 1907 - 2002

Chemistry and Pharmacology

Electronic Resource