Discovery of naked charm particles and lifetime differences among charm species using nuclear emulsion techniques innovated in Japan

This is a historical review of the discovery of naked charm particles and lifetime differences among charm species. These discoveries in the field of cosmic-ray physics were made by the innovation of nuclear emulsion techniques in Japan. A pair of naked charm particles was discovered in 1971 in a cosmic-ray interaction, three years prior to the discovery of the hidden charm particle, J/Ψ, in western countries. Lifetime differences between charged and neutral charm particles were pointed out in 1975, which were later re-confirmed by the collaborative Experiment E531 at Fermilab. Japanese physicists led by K.Niu made essential contributions to it with improved emulsion techniques, complemented by electronic detectors. This review also discusses the discovery of artificially produced naked charm particles by us in an accelerator experiment at Fermilab in 1975 and of multiple-pair productions of charm particles in a single interaction in 1987 by the collaborative Experiment WA75 at CERN

Measurement of the 24Mg(p,t) 22Mg reaction and implications for the 21Na(p, γ) 22Mg stellar reaction rate

Levels in 22Mg between 4 and 7 MeV excitation energy have been populated in a high-resolution study of the 24Mg(p,t) 22Mg reaction. Two new states have been observed at energies Ex = 5090 and 6323 keV, while two states were observed at 5962 and 6046 keV. The precision in measured excitation energies for several other 22Mg levels has been improved substantially. In addition, a new state at 8141 keV was observed in 23Mg. Using spin and parity restrictions from the present and previous work, we discuss T = 1 analog state assignments of A = 22 nuclei below 7 MeV excitation energy. The implications for the rate of the stellar reaction 21Na(p, γ) 22Mg which takes part in hydrogen burning during nova outbursts are presented

Searches for Higgs boson pair production in the hh→bbττ, γγWW∗, γγbb, bbbb channels with the ATLAS detector

Searches for both resonant and nonresonant Higgs boson pair production are performed in the hh→bbττ, γγWW∗ final states using 20.3  fb−1 of pp collision data at a center-of-mass energy of 8 TeV recorded with the ATLAS detector at the Large Hadron Collider. No evidence of their production is observed and 95% confidence-level upper limits on the production cross sections are set. These results are then combined with the published results of the hh→γγbb, bbbb analyses. An upper limit of 0.69 (0.47) pb on the nonresonant hh production is observed (expected), corresponding to 70 (48) times the SM gg→hh cross section. For production via narrow resonances, cross-section limits of hh production from a heavy Higgs boson decay are set as a function of the heavy Higgs boson mass. The observed (expected) limits range from 2.1 (1.1) pb at 260 GeV to 0.011 (0.018) pb at 1000 GeV. These results are interpreted in the context of two simplified scenarios of the Minimal Supersymmetric Standard Model

Immediate synergistic effect of a trunk orthosis with joints providing resistive force and an ankle–foot orthosis on hemiplegic gait

Junji Katsuhira,1,2 Sumiko Yamamoto,3 Nodoka Machida,4 Yuji Ohmura,5 Masako Fuchi,6 Mizuho Ohta,7 Setsuro Ibayashi,7 Arito Yozu,8 Ko Matsudaira2 1Department of Prosthetics and Orthotics and Assistive Technology, Faculty of Medical Technology, Niigata University of Health and Welfare, Niigata, 2Department of Medical Research and Management for Musculoskeletal Pain, 22nd Century Medical and Research Center, The University of Tokyo, Tokyo, 3Graduate School of International University of Health and Welfare, Tokyo, 4International University of Health and Welfare, School of Health Sciences at Narita, Department of Physical Therapy, Chiba, 5International University of Health and Welfare, School of Health Sciences at Odawara, Department of Physical Therapy, Kanagawa, 6Department of Occupational Therapy, Kyusyu Nutrition Welfare University, Fukuoka, 7Seiai Rehabilitation Hospital, Fukuoka, 8Center for Medical Sciences, Ibaraki Prefectural University of Health Science, Ibaraki, Japan Purpose: The synergistic effects of a trunk orthosis and an ankle–foot orthosis (AFO) in stroke patients with a hemiplegic gait are unclear. We previously developed a trunk orthosis with joints providing resistive force (TORF) to modify malalignment of the trunk and pelvis and confirmed its positive effects in stroke patients during level walking without an AFO. The aim of the present study was to determine if this trunk orthosis and an AFO have synergistic effects during level walking in community-dwelling patients with chronic stroke. Methods: Twenty-eight community-dwelling stroke patients performed level walking at a self-selected speed with an AFO and again while wearing a TORF (TORF group) or a corset (control group). Spatiotemporal, kinematic, and kinetic data were recorded using a three-dimensional motion analysis system. Results: When compared with the control group, the TORF group showed significant increases in walking speed, number of steps on the paretic leg per minute, and peak ankle plantar flexion moment during the single stance phase. Conclusion: The TORF increased the ankle joint plantar flexion moment at the end of the single stance phase during level walking in stroke patients, leading to an increase in their gait speed because of the modified trunk and pelvis alignment. Keywords: biomechanics, orthosis, gait, stroke, joint moment, motion analysi

Self-Assembled Biradical Ureabenzene Nanoparticles for Magnetic Resonance Imaging

As part of a series of investigations related to the construction of metal-free magnetic resonance imaging (MRI) contrast agents as alternatives to gadolinium agents, water-soluble biradicals, denoted as 1-AMP and 2-HEG, were prepared, in which two stable radicals were introduced to a ureabenzene framework. We found that 1-AMP possessed an amphiphilic side chain that consisted of an alkyl group and a hexaethylene glycol (HEG) chain, whereas 2-HEG possessed only an HEG chain. Accordingly, the biradicals showed self-assembly behavior due to multiple intermolecular interactions through which nanoparticles were formed in a water solution. Magnetic interaction took place in both biradicals, and the estimated interaction strength was J = 5.4 mT. Through MRI measurement, the water proton relaxivities, r1, were estimated to be 0.12 and 0.41 mM–1 s–1 for 1-AMP and 2-HEG, respectively; in other words, the r1 value for 2-HEG was approximately twice as high as that of monoradical-based contrast agents

Influenza in pregnancy

Objectives: This study was performed to determine whether multiparous pregnant women are prone to influenza. Methods: A questionnaire survey was conducted at 19 centres located throughout Japan, targeting all 6694 postpartum women within 7 days after birth before leaving the hospital. All women gave birth during the study period between March 1, 2015, and July 31, 2015. Data regarding vaccination and influenza infection in or after October 2014, age, previous experience of childbirth, and number and ages of cohabitants were collected. Results: Seventy-eight percent (n = 5,197) of women given questionnaires responded. Of these, 2,661 (51%) and 364 (7.0%) women reported having been vaccinated and having contracted influenza, respectively. Multiparous women had a higher risk of influenza regardless of vaccination status (8.9% [121/1,362] vs. 5.7% [74/1,299], relative risk [95% confidence interval], 1.80 [1.36 to 2.38] for vaccinated and 9.3% [112/1,198] vs. 4.3% [57/1,328], 2.18 [1.60 to 2.97] for unvaccinated women) compared to primiparous women. The risk of influenza increased with increasing number of cohabitants: 4.8% (100/2,089), 7.5%, (121/1,618), 9.0%, (71/785), and 10.4% (58/557) for women with 1, 2, 3, and ≥ 4 cohabitants, respectively. Conclusions: Family size is a risk factor for influenza infection in pregnancy