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Many experiments on neutrinoless double beta decays have been proposed recently for determining the effective mass of neutrinos. Some of them use a plastic scintillator for measuring the beta-ray energy. Achieving a high energy resolution is critical for neutrinoless double beta decay experiments (e.g., MOON and superNEMO). The motivation of this study is to investigate the energy resolution of a plastic scintillation detector in terms of 'components' in the MeV-electron region. It is known that the total energy resolution of a plastic scintillation detector for a monoenergetic spectrum consists of two components: statistical and intrinsic energy resolution. In this paper, these two components were investigated for electrons. Experiments on protons were also performed for the purpose of comparison. Three additional experiments were performed to determine (1) the uniformity of the plastic scintillator materials by scanning a 2.8-MeV proton microbeam, (2) the energy spread of electrons and protons, and (3) the effect of the electron-beam size on the set-up. These additional experiments were performed to ensure that these factors did not affect measurements of the two above-mentioned components. Index Terms--Energy resolution, scintillation detectors.

A 15-year-old boy with refractory juvenile rheumatoid arthritis (JRA) underwent intense immunosuppressive therapy followed by purified blood CD34+ cell autografting. He had been taking prednisolone (PDN) daily or every other day combined with methotrexate once a week to control the disease for 7 years. He suffered from psychological complications and a very short stature due to the adverse effects of these drugs. CD34+ cells were purified in bulk from G-CSF-mobilized PBSC using an Isolex 300. After the administration of cyclophosphamide (200 mg/kg) and anti-lymphocyte globulin (45 mg/kg), 3.6 × 106/kg purified CD34+ cells were infused. his post-transplant course was uneventful except for herpes-zoster infection. he is now more than 1 year post transplant and has not taken any immunosuppressive medication. his rate of growth has increased (>10 cm/year) due to the effects of the cessation of PDN and the administration of recombinant human growth hormone (rGH), in contrast to the gain of 2 cm in the preceding 3 years with rGH treatment. Although the durability of this remission is unknown, intense immunosuppressive therapy followed by purified blood CD34+ cell autografting might be acceptable for adolescent patients with refractory JRA to achieve a drug-free period for physical and psychological maturation. Bone Marrow Transplantation (2001) 27, 333–336. [ABSTRACT FROM AUTHOR]

The solid particles or liquid droplets entrained by multi-phase flow in process plants can cause erosion resulting in pipe wall thinning. Hence, it is essential to evaluate erosion rate for determining design margin and taking counter-measures. Many models have been proposed for prediction of erosion induced by particles and droplets, but there is significant difference in their prediction accuracy. The present study aims at verifying prediction accuracy of some major erosion models using the published experimental data, for engineering applications. CFD benchmark simulations were conducted for different flow velocities and piping geometries to investigate prediction accuracy of particle-induced erosion rates for five major erosion models, using the experimental data in literature. CFD results show that the erosion rates predicted by Grant and Tabakoff model are closest to the experimental results with acceptable prediction accuracy for engineering applications. At the same time, CFD benchmark simulations were also carried out to verify the prediction accuracy of droplet induced erosion rates for three erosion models, using the published experimental data. CFD results show that the erosion rates predicted by Haugen model for all the water impingement velocities are closest to the experimental results with acceptable prediction accuracy for engineering applications.

Abstract Remarkable progress has been made during the past ten years in elucidating the structure of the bacteriophage T4 tail by a combination of three-dimensional image reconstruction from electron micrographs and X-ray crystallography of the components. Partial and complete structures of nine out of twenty tail structural proteins have been determined by X-ray crystallography and have been fitted into the 3D-reconstituted structure of the "extended" tail. The 3D structure of the "contracted" tail was also determined and interpreted in terms of component proteins. Given the pseudo-atomic tail structures both before and after contraction, it is now possible to understand the gross conformational change of the baseplate in terms of the change in the relative positions of the subunit proteins. These studies have explained how the conformational change of the baseplate and contraction of the tail are related to the tail's host cell recognition and membrane penetration function. On the other hand, the baseplate assembly process has been recently reexamined in detail in a precise system involving recombinant proteins (unlike the earlier studies with phage mutants). These experiments showed that the sequential association of the subunits of the baseplate wedge is based on the induced-fit upon association of each subunit. It was also found that, upon association of gp53 (gene product 53), the penultimate subunit of the wedge, six of the wedge intermediates spontaneously associate to form a baseplate-like structure in the absence of the central hub. Structure determination of the rest of the subunits and intermediate complexes and the assembly of the hub still require further study.

In eukaryotes, Dmc1 and Rad51 are key proteins of homologous recombination. The Swi5-Sfr1 complex in fission yeast, a conserved auxiliary factor, stimulates DNA strand exchange driven by both Dmc1 and Rad51. Interestingly, biochemical analysis suggested that Swi5-Sfr1 regulates strand exchange activities of these recombinases differently, but the mechanisms were unclear. We previously developed a real-time system to analyze Rad51-driven DNA strand exchange and identified two topologically distinct three-stranded intermediates (complex 1 (C1) and complex 2 (C2)). Swi5-Sfr1 facilitates the C1-C2 transition and releases single-stranded DNA (ssDNA) from C2, acting as a strand exchange activator. In this study, we investigated fission yeast Dmc1-driven DNA strand exchange and the role of Swi5-Sfr1 in Dmc1 activity in real-time. Kinetic analysis revealed a three-step model for the Dmc1-driven reaction, similar to that of Rad51. Although Swi5-Sfr1 stimulated the Dmc1-driven reaction, it had a weaker impact than Rad51. Furthermore, Swi5-Sfr1 enhanced the association of Dmc1 with ssDNA by promoting filament nucleus formation, acting as a mediator, unlike its role with Rad51. This stimulation mechanism also differs from that of Ca2+ or ATP analog, AMP-PNP. Our findings suggest that Swi5-Sfr1 stimulates strand exchange activities of Dmc1 and Rad51 via different reaction steps., (© The Author(s) 2024. Published by Oxford University Press on behalf of Nucleic Acids Research.)

Methicillin-resistant Staphylococcus spp. present challenges in clinical and veterinary settings because effective antimicrobial agents are limited. Phage-encoded peptidoglycan-degrading enzyme, endolysin, is expected to be a novel antimicrobial agent. The enzymatic activity has recently been shown to be influenced by the linker between functional domains in the enzyme. S6_ORF93 (ORF93) is one of the endolysins derived from previously isolated Staphylococcus giant phage S6. The ORF93 was speculated to have a catalytic and peptidoglycan-binding domain with a long linker. In this study, we examined the influence of linker shortening on the characteristics of ORF93. We produce wild-type ORF93 and the linker deletion mutants using an Escherichia coli expression system. These mutants were designated as ORF93-Δ05, ORF93-Δ10, ORF93-Δ15, and ORF93-Δ20, from which 5, 10, 15, and 20 amino acids were removed from the linker, respectively. Except for the ORF93-Δ20, ORF93 and its mutants were expressed as soluble proteins. Moreover, ORF93-Δ15 showed the highest yield and bacteriolytic activity, while the antimicrobial spectrum was homologous. The cold storage experiment showed a slight effect by the linker deletion. According to our results and other studies, linker investigations are crucial in endolysin development., Competing Interests: The authors declare that no competing interests exist., (Copyright: © 2024 Munetomo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Introduction: Antimicrobial susceptibility patterns of bacterial pathogens isolated from patients with complicated urinary tract infections were analyzed using the national surveillance data, comprising 793 bacterial strains from eight clinically relevant species., Materials and Methods: Data were collected for the fourth national surveillance project from July 2020 to December 2021 by the Japanese Society of Chemotherapy, the Japanese Association for Infectious Disease, and the Japanese Society of Clinical Microbiology. Surveillance was supervised with the cooperation of 43 medical institutions throughout Japan., Results: Fluoroquinolone required a minimum inhibitory concentration (MIC) of 2-64 mg/L to inhibit the 330 tested Escherichia coli strains. The proportion of levofloxacin-resistant E. coli strains increased from 28.6% in 2008 to 29.6% in 2011, 38.5% in 2015, and 44.5% in 2021. The proportion of levofloxacin-resistant strains of Pseudomonas aeruginosa also increased from previous survey results, showing a continuing downward trend. Conversely, the proportion of levofloxacin-resistant strains of Enterococcus faecalis decreased relative to previous reports. Neither multidrug-resistant P. aeruginosa nor carbapenem-resistant Enterobacteriaceae were detected. For methicillin-resistant Staphylococcus aureus (MRSA), the proportion of vancomycin-susceptible strains (MIC of 2 μg/mL) decreased from 14.7% to 7.7%., Discussion: Bacterial strains that produced extended-spectrum β-lactamase included E. coli (82/330 strains, 24.8%), Klebsiella pneumoniae (11/68 strains, 16.2%), and Proteus mirabilis (4/26 strains, 15.4%). As compared to previous surveillance reports, these strains showed an increase in proportion over the years., Competing Interests: Declaration of competing interest Satoshi Takahashi received speaker honoraria from Fujirebio Inc. and research funding from Shino-Test Corporation, Roche Diagnostic K. K., Fujirebio Inc., and Abbott Japan Co., Ltd. Koichiro Wada received speaker honoraria from Janssen Pharmaceutical K.K., and MSD K.K. Shingo Yamamoto received speaker honoraria from MSD K.K., Fuso Pharmaceutical Industries, Ltd., Daiichi Sankyo Co., Ltd. and scholarship donations from Takeda Pharmaceutical Co., Ltd., Nippon Shinyaku Co., Ltd., Ono Pharmaceutical Co., Ltd., Bayer Yakuhin, Ltd. and research funding from Takeda Pharmaceutical Co., Ltd. Tetsuya Matsumoto received speaker honoraria from MSD K.K., Pfizer Japan Inc., and Kyorin Pharmaceutical Co., Ltd., and research funding from Kewpie Corporation., Biofermin Pharmaceutical Co., Ltd. Kazumasa Matsumoto received research funding from Sysmex Corporation. Tohru Nakagawa received speaker honoraria from Astellas Pharma Inc., AstraZeneca K.K., Ono Pharmaceutical Co., Ltd., and Janssen Pharmaceutical K.K., (Copyright © 2024 Japanese Society of Chemotherapy, Japanese Association for Infectious Diseases, and Japanese Society for Infection Prevention and Control. Published by Elsevier Ltd. All rights reserved.)