150 research outputs found
A Search for deviations from the inverse square law of gravity at nm range using a pulsed neutron beam
We describe an experimental search for deviations from the inverse square law
of gravity at the nanometer length scale using neutron scattering from noble
gases on a pulsed slow neutron beamline. By measuring the neutron momentum
transfer () dependence of the differential cross section for xenon and
helium and comparing to their well-known analytical forms, we place an upper
bound on the strength of a new interaction as a function of interaction length
which improves upon previous results in the region nm, and remains competitive in the larger region. A
pseudoexperimental simulation developed for this experiment and its role in the
data analysis described. We conclude with plans for improving sensitivity in
the larger region.Comment: 8 pages, 8 figure
Royal Jelly Facilitates Restoration of the Cognitive Ability in Trimethyltin-Intoxicated Mice
Trimethyltin (TMT) is a toxic organotin compound that induces acute neuronal death selectively in the hippocampal dentate gyrus (DG) followed by cognition impairment; however the TMT-injured hippocampal DG itself is reported to regenerate the neuronal cell layer through rapid enhancement of neurogenesis. Neural stem/progenitor cells (NS/NPCs) are present in the adult hippocampal DG, and generate neurons that can function for the cognition ability. Therefore, we investigated whether royal jelly (RJ) stimulates the regenerating processes of the TMT-injured hippocampal DG, and found that orally administered RJ significantly increased the number of DG granule cells and simultaneously improved the cognitive impairment. Furthermore, we have already shown that RJ facilitates neurogenesis of cultured NS/NPCs. These present results, taken together with previous observations, suggest that the orally administered RJ may be a promising avenue for ameliorating neuronal function by regenerating hippocampal granule cells that function in the cognition process
Measurement of the total neutron scattering cross section ratios of noble gases of natural isotopic composition using a pulsed neutron beam
Precision measurements of slow neutron cross sections with atoms have several
scientific applications. In particular the n-He s-wave scattering length
is important to know both for helping to constrain the nuclear three-body
interaction and for the proper interpretation of several ongoing slow neutron
experiments searching for other types of neutron-atom interactions. We present
new measurements of the ratios of the neutron differential scattering cross
sections for natural isotopic-abundance mixtures of the noble gases He, Ar, Kr,
and Xe to natural isotopic abundance Ne. These measurements were performed
using a recently developed neutron scattering apparatus for gas samples located
on a pulsed slow neutron beamline which was designed to search for possible
exotic neutron-atom interactions and employs both neutron time of flight
information and a position-sensitive neutron detector for scattering event
reconstruction. We found agreement with the literature values of scattering
cross sections inferred from Ar/Ne, Kr/Ne and Xe/Ne differential cross section
ratios over the range of nm. However for the case of He/Ne
we find that the cross section inferred differs by 11.3% (7.6 ) from
previously-reported values inferred from neutron phase shift measurements, but
is in reasonable agreement with values from other measurements. The very large
discrepancy in the He/Ne ratio calls for a new precision measurement of the
n-He scattering length using neutron interferometry
AMP N1-oxide, a unique compound of royal jelly, induces neurite outgrowth from PC12 cells via signaling by protein kinase A independent of that by mitogen-activated protein kinase
Earlier we identified adenosine monophosphate (AMP) N1-oxide as a unique compound of royal jelly (RJ) that induces neurite outgrowth (neuritegenesis) from cultured rat pheochromocytoma PC12 cells via the adenosine A2A receptor. Now, we found that AMP N1-oxide stimulated the phosphorylation of not only mitogen-activated protein kinase (MAPK) but also that of cAMP/calcium-response element-binding protein (CREB) in a dose-dependent manner. Inhibition of MAPK activation by a MEK inhibitor, PD98059, did not influence the AMP N1-oxide-induced neuritegenesis, whereas that of protein kinase A (PKA) by a selective inhibitor, KT5720, significantly reduced neurite outgrowth. AMP N1-oxide also had the activity of suppressing the growth of PC12 cells, which correlated well with the neurite outgrowth-promoting activity. KT5720 restored the growth of AMP N1-oxide-treated PC12 cells. It is well known that nerve growth factor suppresses proliferation of PC12 cells before causing stimulation of neuronal differentiation. Thus, AMP N1-oxide elicited neuronal differentiation of PC12 cells, as evidenced by generation of neurites, and inhibited cell growth through adenosine A2A receptor-mediated PKA signaling, which may be responsible for characteristic actions of RJ
Fundamental physics activities with pulsed neutron at J-PARC(BL05)
"Neutron Optics and Physics (NOP/ BL05)" at MLF in J-PARC is a beamline for
studies of fundamental physics. The beamline is divided into three branches so
that different experiments can be performed in parallel. These beam branches
are being used to develop a variety of new projects. We are developing an
experimental project to measure the neutron lifetime with total uncertainty of
1 s (0.1%). The neutron lifetime is an important parameter in elementary
particle and astrophysics. Thus far, the neutron lifetime has been measured by
several groups; however, different values are obtained from different
measurement methods. This experiment is using a method with different sources
of systematic uncertainty than measurements conducted to date. We are also
developing a source of pulsed ultra-cold neutrons (UCNs) produced from a
Doppler shifter are available at the unpolarized beam branch. We are developing
a time focusing device for UCNs, a so called "rebuncher", which can increase
UCN density from a pulsed UCN source. At the low divergence beam branch, an
experiment to search an unknown intermediate force with nanometer range is
performed by measuring the angular dependence of neutron scattering by noble
gases. Finally the beamline is also used for the research and development of
optical elements and detectors. For example, a position sensitive neutron
detector that uses emulsion to achieve sub-micrometer resolution is currently
under development. We have succeeded in detecting cold and ultra-cold neutrons
using the emulsion detector.Comment: 9 pages, 5 figures, Proceedings of International Conference on
Neutron Optics (NOP2017
Polychlorinated biphenyl (118) activates osteoclasts and induces bone resorption in goldfish
To analyze the effect of polychlorinated biphenyl (PCB) 118 on fish bone metabolism, we examined osteoclastic and osteoblastic activities, as well as plasma calcium levels, in the scales of PCB (118)-injected goldfish. In addition, effect of PCB (118) on osteoclasts and osteoblasts was investigated in vitro. Immature goldfish, in which the endogenous effects of sex steroids are negligible, were used. PCB (118) was solubilized in dimethyl sulfoxide at a concentration of 10 ppm. At 1 and 2 days after PCB (118) injection (100 ng/g body weight), both osteoclastic and osteoblastic activities, and plasma calcium levels were measured. In an in vitro study, then, both osteoclastic and osteoblastic activities as well as each marker mRNA expression were examined. At 2 days, scale osteoclastic activity in PCB (118)-injected goldfish increased significantly, while osteoblastic activity did not change significantly. Corresponding to osteoclastic activity, plasma calcium levels increased significantly at 2 days after PCB (118) administration. Osteoclastic activation also occurred in the marker enzyme activities and mRNA expressions in vitro. Thus, we conclude that PCB (118) disrupts bone metabolism in goldfish both in vivo and in vitro experiments. © 2012 The Author(s)
コーディネーター介入による在宅虚弱高齢者同士のテレビ電話を活用したネットワーク形成
在宅虚弱高齢者の社会的孤立感の解消や自立生活の助長をはかることを目的として、在宅虚弱高齢者同士のネットワークをテレビ電話を活用し、コーディネーターの介入により形成する試みを開始した。対象者及びネットワークの形成を促進するコーディネーターを選定した後、対象者にテレビ電話を設置し評価基準を定めて介入をした。2ヶ月間の介入をした段階で、在宅虚弱高齢者同士のネットワークの形成に向けての動きが見られた
Discrimination and Blend Ratio Estimation between Arabica and Robusta Coffee Species Using Direct Inlet Probe/Ion Attachment Ionization Mass Spectrometry
Royal jelly-induced neurite outgrowth from rat pheochromocytoma PC12 cells requires integrin signal independent of activation of extracellular signalregulated kinases
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