523 research outputs found
Angular Distribution of -rays from Neutron-Induced Compound States of La
Angular distribution of individual -rays, emitted from a
neutron-induced compound nuclear state via radiative capture reaction of
La(n,) has been studied as a function of incident neutron
energy in the epithermal region by using germanium detectors.
An asymmetry was defined as , where and
are integrals of low and high energy region of a neutron resonance
respectively, and we found that has the angular dependence of
, where is emitted angle of
-rays, with and in 0.74 eV
p-wave resonance.
This angular distribution was analyzed within the framework of interference
between s- and p-wave amplitudes in the entrance channel to the compound
nuclear state, and it is interpreted as the value of the partial p-wave neutron
width corresponding to the total angular momentum of the incident neutron
combined with the weak matrix element, in the context of the mechanism of
enhanced parity-violating effects. Additionally we used the result to quantify
the possible enhancement of the breaking of the time-reversal invariance in the
vicinity of the p-wave resonance.Comment: 14pages, 25 figure
Pulsed UCN production using a Doppler shifter at J-PARC
We have constructed a Doppler-shifter-type pulsed ultra-cold neutron (UCN)
source at the Materials and Life Science Experiment Facility (MLF) of the Japan
Proton Accelerator Research Complex (J-PARC). Very-cold neutrons (VCNs) with
136- velocity in a neutron beam supplied by a pulsed neutron
source are decelerated by reflection on a m=10 wide-band multilayer mirror,
yielding pulsed UCN. The mirror is fixed to the tip of a 2,000-rpm rotating arm
moving with 68- velocity in the same direction as the VCN. The
repetition frequency of the pulsed UCN is and the time width
of the pulse at production is . In order to increase the UCN
flux, a supermirror guide, wide-band monochromatic mirrors, focus guides, and a
UCN extraction guide have been newly installed or improved. The
-equivalent count rate of the output neutrons with longitudinal
wavelengths longer than is ,
while that of the true UCNs is . The spatial density at
production is . This new UCN source enables us to
research and develop apparatuses necessary for the investigation of the neutron
electric dipole moment (nEDM).Comment: 32 pages, 15 fugures. A grammatical error was fixe
Pulsed neutron time-dependent intensity modulation for quasi-elastic neutron scattering spectroscopy
We propose a basic formula and demonstration for a high-resolution quasi-elastic neutron scattering (QENS) by combining the time-of-flight (TOF) method with Modulation of Intensity by Zero Effort (MIEZE) type neutron spin echo spectroscopy. The MIEZE technique has the potential to develop a unique approach to study on slow dynamics of condensed matter; however, the energy resolution is limited owing to the hypersensitivity of the MIEZE signal contrast to the echo condition, which is strongly affected by the alignment of the instruments and the sample. The narrow allowance of the optimal alignment is a major obstacle to the wide use of this technique. Combining the TOF method with MIEZE (TOF-MIEZE), the hypersensitivity of MIEZE signals is significantly alleviated with a short pulsed beam. This robustness is very useful to optimize experimental alignments and enables accurate measurements of QENS. The experimental results demonstrate the characteristic of the TOF-MIEZE technique and are well described by the formula presented in this study
Towards a high-resolution TOF-MIEZE spectrometer with very cold neutrons
We report the first experimental test of TOF-MIEZE technique using very cold neutrons (VCNs) towards high-resolution quasi-elastic neutron scattering spectroscopy. TOF-MIEZE is a type of neutron resonance spin echo spectroscopy with a combination of the time-of-flight (TOF) method and modulation of intensity by zero effort (MIEZE). A compact MIEZE instrument was constructed at the VCN beam port at the High Flux Reactor at the Institut Laue Langevin. By accumulating individual oscillations of raw data, we observed a TOF-MIEZE signal with an effective frequency of 50 kHz in a wavelength band of 4ā6 nm. The signal contrasts were 0.59 Ā± 0.04 and 0.29 Ā± 0.03 for wavelengths of 4 nm and 6 nm, respectively. The Fourier time was estimated to be 70 ns with 6 nm VCNs in the experimental set-up
Effects of bronchodilators on dynamic hyperinflation following hyperventilation in patients with COPD
āThe definitive version is available at www.blackwell-synergy.com '.ArticleRespirology. 12(1): 93-99 (2007)journal articl
Oxygen ultra-fine bubbles water administration prevents bone loss of glucocorticoid-induced osteoporosis in mice by suppressing osteoclast differentiation
Summary: Oxygen ultra-fine bubbles (OUB) saline injection prevents bone loss of glucocorti\coid-induced osteoporosis in mice, and OUB inhibit osteoclastogenesis via RANK-TRAF6-c-Fos-NFATc1 signaling and RANK-p38 MAPK signaling in vitro. Introduction: Ultra-fine bubbles (<200Ā nm in diameter) have several unique properties, and they are tested in various medical fields. The purpose of this study was to investigate the effects of oxygen ultra-fine bubbles (OUB) on glucocorticoid-induced osteoporosis (GIO) model mice. Methods: Prednisolone (PSL, 5Ā mg) was subcutaneously inserted in 6-month-old male C57BL/6J mice, and 200Ā Ī¼l of saline, OUB-diluted saline, or nitrogen ultra-fine bubbles (NUB)-diluted saline was intraperitoneally injected three times per week for 8Ā weeks the day after operations. Mice were divided into four groups; (1) control, sham-operationĀ +Ā saline; (2) GIO, PSLĀ +Ā saline; (3) GIOĀ +Ā OUB, PSLĀ +Ā OUB saline; (4) GIOĀ +Ā NUB, PSLĀ +Ā NUB saline. The effects of OUB on osteoblasts and osteoclasts were examined by serially diluted OUB medium in vitro. Results: Bone mass was significantly decreased in GIO [bone volume/total volume (%): control vs. GIO 12.6 vs. 7.9; pĀ <Ā 0.01] while significantly preserved in GIOĀ +Ā OUB (GIO vs. GIOĀ +Ā OUB 7.9 vs. 12.9; pĀ <Ā 0.05). In addition, tartrate-resistant acid phosphatase (TRAP)-positive cells in the distal femur [mean osteoclasts number/bone surface (mmā1)] was significantly increased in GIO (control vs. GIO 6.8 vs. 11.6; pĀ <Ā 0.01) while suppressed in GIOĀ +Ā OUB (GIO vs. GIOĀ +Ā OUB 11.6 vs. 7.5; pĀ <Ā 0.01). NUB did not affect these parameters. In vitro experiments revealed that OUB significantly inhibited osteoclastogenesis by inhibiting RANK-TRAF6-c-Fos-NFATc1 signaling, RANK-p38 MAPK signaling, and TRAP/Cathepsin K/DC-STAMP mRNA expression in a concentration-dependent manner. OUB did not affect osteoblastogenesis in vitro. Conclusions: OUB prevent bone loss in GIO mice by inhibiting osteoclastogenesis.This version of the article has been accepted for publication, after peer review (when applicable) and is subject to Springer Natureās AM terms of use, but is not the Version of Record and does not reflect post-acceptance improvements, or any corrections. The Version of Record is available online at: https://doi.org/10.1007/s00198-016-3830-1Noguchi T., Ebina K., Hirao M., et al. Oxygen ultra-fine bubbles water administration prevents bone loss of glucocorticoid-induced osteoporosis in mice by suppressing osteoclast differentiation. Osteoporosis International 28, 1063 (2017); https://doi.org/10.1007/s00198-016-3830-1
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