25 research outputs found
Long-lived neutral-kaon flux measurement for the KOTO experiment
The KOTO ( at Tokai) experiment aims to observe the CP-violating rare
decay by using a long-lived neutral-kaon
beam produced by the 30 GeV proton beam at the Japan Proton Accelerator
Research Complex. The flux is an essential parameter for the measurement
of the branching fraction. Three neutral decay modes, , , and were used to
measure the flux in the beam line in the 2013 KOTO engineering run. A
Monte Carlo simulation was used to estimate the detector acceptance for these
decays. Agreement was found between the simulation model and the experimental
data, and the remaining systematic uncertainty was estimated at the 1.4\%
level. The flux was measured as per protons on a
66-mm-long Au target.Comment: 27 pages, 16 figures. To be appeared in Progress of Theoretical and
Experimental Physic
Ceruloplasmin Protects Against Rotenone-Induced Oxidative Stress and Neurotoxicity
To clarify the neuroprotective property of ceruloplasmin and the pathogenesis of aceruloplasminemia, we generated ceruloplasmin-deficient (CPā/ā) mice on the C57BL/10 genetic background and further treated them with a mitochondrial complex I inhibitor, rotenone. There was no iron accumulation in the brains of CPā/ā mice at least up to 60Ā weeks of age. Without rotenone treatment, CPā/ā mice showed slight motor dysfunction compared with CP+/+ mice, but there were no detectable differences in the levels of oxidative stress markers between these two groups. A low dose of rotenone did not affect the mitochondrial complex I activity in our mice, however, it caused a significant change in motor behavior, neuropathology, or the levels of oxidative stress markers in CPā/ā mice, but not in CP+/+ mice. Our data support that ceruloplasmin protects against rotenone-induced oxidative stress and neurotoxicity, probably through its antioxidant properties independently of its function of iron metabolism
A saposin deficiency model in Drosophila: Lysosomal storage, progressive neurodegeneration and sensory physiological decline
Saposin deficiency is a childhood neurodegenerative lysosomal storage disorder (LSD) that can cause premature death within three months of life. Saposins are activator proteins that promote the function of lysosomal hydrolases that mediate the degradation of sphingolipids. There are four saposin proteins in humans, which are encoded by the prosaposin gene. Mutations causing an absence or impaired function of individual saposins or the whole prosaposin gene lead to distinct LSDs due to the storage of different classes of sphingolipids. The pathological events leading to neuronal dysfunction induced by lysosomal storage of sphingolipids are as yet poorly defined. We have generated and characterised a Drosophila model of saposin deficiency that shows striking similarities to the human diseases. Drosophila saposin-related (dSap-r) mutants show a reduced longevity, progressive neurodegeneration, lysosomal storage, dramatic swelling of neuronal soma, perturbations in sphingolipid catabolism, and sensory physiological deterioration. Our data suggests a genetic interaction with a calcium exchanger (Calx) pointing to a possible calcium homeostasis deficit in dSap-r mutants. Together these findings support the use of dSap-r mutants in advancing our understanding of the cellular pathology implicated in saposin deficiency and related LSDs
POEMS syndrome and calciphylaxis: an unrecognized cause of abnormal small vessel calcification
Application of Partial Least Square on Quantitative Analysis of L-, D-, and DL-Tartaric Acid by Terahertz Absorption Spectra
Suspected Adverse Effects After Human Papillomavirus Vaccination: A Temporal Relationship Between Vaccine Administration and the Appearance of Symptoms in Japan
A new search for the and decays
We searched for the CP-violating rare decay of the neutral kaon, KLāĻ0Ī½Ī½ĀÆ, in data from the first 100 hours of physics running in 2013 of the J-PARC KOTO experiment. One candidate event was observed while 0.34Ā±0.16 background events were expected. We set an upper limit of 5.1Ć10ā8 for the branching fraction at the 90% confidence level (C.L.). An upper limit of 3.7Ć10ā8 at the 90% C.L. for the KLāĻ0X0 decay was also set for the first time, where X0 is an invisible particle with a mass of 135āMeV/c2.We searched for the -violating rare decay of neutral kaon, , in data from the first 100 hours of physics running in 2013 of the J-PARC KOTO experiment. One candidate event was observed while background events were expected. We set an upper limit of for the branching fraction at the 90\% confidence level (C.L.). An upper limit of at the 90\% C.L. for the decay was also set for the first time, where is an invisible particle with a mass of 135 MeV/