JSNS
2
(J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) is an experiment that searches for sterile neutrinos via the observation of
ν
¯
μ
→
ν
¯
e
appearance oscillations using ...muon decay-at-rest neutrinos. The JSNS
2
experiment performed data taking from 2021. In this manuscript, a study of the accidental background is presented. The rate of the accidental background is (
9.29
±
0.39
)
×
10
-
8
/spill with 0.75 MW beam power and comparable to the expected number of signal events.
The Belle II experiment is a high-energy physics experiment at the SuperKEKB electron-positron collider. Using Belle II data, high-precision measurement of rare decays and CP-violation in heavy ...quarks and leptons will be performed to probe new physics beyond the standard model. In this article, we present the archiver system used to store the monitoring data of the Belle II detector and discuss in particular how we manage the operation of this system. We currently record about 23 000 variables including the operation conditions of various components of subdetectors, status of data acquisition, and luminosity information of the colliding beams. For stable data taking, it is essential to collect and archive these variables. We ensure that all the variables from the subdetectors and other systems, as well as the status of the archiver itself, are available, consistent, and regularly updated. To deal with a possible hardware failure, we prepared a backup archiver that is synchronized with the main archiver. The archiver has been successfully running over the Belle II operation period.
In the forward end-cap of the Belle II spectrometer, particle identification is provided by a proximity focusing RICH detector with an aerogel radiator (ARICH). The ARICH’s primary function is to ...effectively distinguish between pions and kaons in the momentum range of 0.5GeV/c to about 4GeV/c, as well as to contribute to identification of low-momentum leptons. Since its operation began, Belle II has collected over 420fb−1 of data. Based on this large data sample, studies of several effects that impact the performance of the ARICH detector were carried out. In this paper, we present a comparison of the observed Cherenkov ring image and detector particle identification performance in the measured data and detector simulation. Furthermore, we highlight recent efforts aimed at enhancing the ARICH’s performance by taking into account the effects of particle decay in flight and scattering in materials before the detector, as well as by refining the probability density function used for particle identification likelihood evaluation.
We investigated the bioconjugation of enzymes on polymer nanoparticles covered with bioinert phosphorylcholine groups. A water-soluble amphiphilic phospholipid polymer (PMBN) was specially designed ...for preparation of nanoparticles and conjugation with enzymes on them. The PMBN was prepared by random copolymerization of 2-methacryloyloxyethyl phosphorylcholine (MPC), n-butyl methacrylate, and p-nitrophenylester bearing methacrylate. The PMBN was used as an emulsifier and a surface modifier to prepare the poly(l-lactic acid) nanoparticles by a solvent evaporation technique in aqueous medium. The nanoparticles covered with phosphorylcholine groups were stably dispersed in an aqueous solution and a phosphate buffered saline. The diameter and surface ζ-potential of the nanoparticles were ca. 200 nm and −6 mV, respectively. The p-nitrophenyl ester groups, which are active ester units for the amino groups of the protein, were located at the surface of the nanoparticles. Both acetylcholine esterase and choline oxidase were co-immobilized (dual-mode conjugation) by the reaction between the p-nitrophenyl ester group and the amino group of these enzymes. The enzymatic reactions on the nanoparticles were followed using a microdialysis biosensor system with a microtype hydrogen peroxide electrode in the probe. The nanoparticles conjugated with these enzymes could detect the acetylcholine chloride as hydrogen peroxide, which is a product of the enzymatic reactions on the surface of the nanoparticles in the probe. Namely, continuous enzyme reactions could be occurring on the surface of the nanoparticles. It is concluded that the nanoparticles are a promising tool for a highly sensitive and microdiagnostic system.
Paracoccidioidomycosis is a systemic granulomatous disease caused by the dimorphic fungus Paracoccidioides brasiliensis. Its major antigen is a 43 kDa glycoprotein whose peptides embody different ...functions: P10 peptide, a T-cell epitope, induces protective response while P4 and P23 peptides inhibit both, macrophage functions and inflammatory reaction, thus facilitating infection. Here we investigated the modulating mechanisms of the immune response exerted by P4 and P23 involved in the latter inhibitory effect on macrophages. Moreover we analyzed the peptides effects in different models in vivo. While evaluating whether P4 and P23 present systemic anti-inflammatory effects in vivo, we showed that their intraperitonial administration decreased footpad swelling in mice infected with either P. brasiliensis or Mycobacterium bovis. Both, qPCR and ELISA assays suggested that this anti-inflammatory effect depended on alterations in the kinetics of production of innate immunity modulators such as TNF-α, IL6, IL10 and TLR2. IL10 seems to be early produced than TNF-α and IL6, produced later in presence of peptides. Higher doses or intravenously given P4 and P23 resulted in earlier and more prolonged anti-inflammatory effects. Moreover, continuous treatment with P4 and P23 sustained the anti-inflammatory activity throughout.
Background and purpose
Mutations in colony‐stimulating factor 1 receptor (CSF1R) cause adult‐onset leukoencephalopathy with axonal spheroids and pigmented glia (ALSP). Patients with ALSP can be ...misdiagnosed as having acute ischemic stroke due to hyperintensity lesions on diffusion‐weighted magnetic resonance imaging. Mutant CSF1R proteins identified in ALSP show a complete loss of autophosphorylation of CSF1R.
Methods
We conducted mutation screening of CSF1R in 123 patients with definite acute ischemic cerebrovascular syndrome and positive family history of stroke. The pathogenicity of identified variants was evaluated using functional analyses. The levels of autophosphorylation of CSF1R in response to treatment with ligands of CSF1R were examined in cells transfected with wild‐type and mutant CSF1R.
Results
We identified eight CSF1R variants, six were known non‐pathogenic polymorphisms, whereas the other two were missense variants inducing substitution of amino acid residues (p.Glu573Lys and p.Gly747Arg). Functional assay showed that the levels of autophosphorylation of p.Gly747Arg were similar to those of wild‐type when treated with ligands. The autophosphorylation of p.Glu573Lys was detectable, but significantly decreased compared with those of wild‐type CSF1R (P < 0.001, two‐way anova with Bonferroni). The clinical presentation of the patient with p.Glu573Lys was consistent with cerebral embolism. The patient did not have typical clinical findings of ALSP. However, periventricular white matter abnormalities, unrelated to the recent infarct, were evident on brain magnetic resonance imaging.
Conclusions
In contrast to ALSP‐associated missense mutations, CSF1R p.Glu573Lys variant in a patient with acute ischemic cerebrovascular syndrome showed a partial loss of autophosphorylation of CSF1R; its clinical significance warrants further investigation.
Ephrin B1 and its cognate receptor, Eph receptor B2, key regulators of embryogenesis, are expressed in human atherosclerotic plaque and inhibit adult human monocyte chemotaxis. Few data exist, ...however, regarding the gene expression profiles of the ephrin (EFN) and Eph receptor (EPH) family of genes in atherosclerosis-related human cells. Gene expression profiles were determined of all 21 members of this gene family in atherosclerosis-related cells by reverse transcription—polymerase chain reaction analysis. The following 17 members were detected in adult human peripheral blood monocytes: EFNA1 and EFNA3 – EFNA5 (coding for ephrins A1 and A3 – A5); EPHA1, EPHA2, EPHA4 – EPHA6 and EPHA8 (coding for Eph receptors A1, A2, A4 – A6 and A8); EFNB1 and EFNB2 (coding for ephrins B1 and B2); and EPHB1 – EPHB4 and EPHB6 (coding for Eph receptors B1 – B4 and B6). THP-1 monocytic cells, Jurkat T cells and adult arterial endothelial cells also expressed multiple EFN and EPH genes. These results indicate that a wide variety of ephrins and Eph receptors might affect monocyte chemotaxis, contributing to the development of atherosclerosis. Their pathological significance requires further study.
JSNS
2
(J-PARC Sterile Neutrino Search at J-PARC Spallation Neutron Source) is an experiment that is searching for sterile neutrinos via the observation of
ν
¯
μ
→
ν
¯
e
appearance oscillations ...using muon decay-at-rest neutrinos. Before dedicated data taking in the first-half of 2021, we performed a commissioning run for 10 days in June 2020. Using the data obtained in this commissioning run, in this paper, we present an estimate of the correlated background which imitates the
ν
¯
e
signal in a sterile neutrino search. In addition, in order to demonstrate future prospects of the JSNS
2
experiment, possible pulse shape discrimination improvements towards reducing cosmic ray induced fast neutron background are described.
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