The field of cold antimatter physics has rapidly developed in the last 20 years, overlapping with the period of the Antiproton Decelerator (AD) at CERN. The central subjects are CPT symmetry tests ...and Weak Equivalence Principle (WEP) tests. Various groundbreaking techniques have been developed and are still in progress such as to cool antiprotons and positrons down to extremely low temperature, to manipulate antihydrogen atoms, to construct extremely high-precision Penning traps, etc. The precisions of the antiproton and proton magnetic moments have improved by six orders of magnitude, and also laser spectroscopy of antihydrogen has been realized and reached a relative precision of 2 × 10−12 during the AD time. Antiprotonic helium laser spectroscopy, which started during the Low Energy Antiproton Ring (LEAR) time, has reached a relative precision of 8 × 10−10. Three collaborations joined the WEP tests inventing various unique approaches. An additional new post-decelerator, Extra Low ENergy Antiproton ring (ELENA), has been constructed and will be ready in 2021, which will provide 10–100 times more cold antiprotons to each experiment. A new era of the cold antimatter physics will emerge soon including the transport of antiprotons to other facilities.
Studies of charged particle guiding through capillaries in insulating materials, performed during the last decade, are reviewed in a comprehensive manner. First, the principles of capillary guiding ...of slow highly charged ions are introduced describing the self-organized formation of charge patches. Basic quantities are defined, such as the guiding power characterizing a capillary. Challenges of the guiding experiments are pointed out. Then, experiments are described with emphasis on the guiding of highly charged ions in the keV energy range. Samples with an array of nanocapillaries as well as single macrocapillaries are treated. Emission profiles of transmitted ions are analyzed to establish scaling laws for the guiding angle, which quantifies the guiding power. Oscillations of the mean ion emission angle reveal the temporal dynamics of the charge patch formation. Next, experiments with ions of high (MeV) energies are focused on single tapered capillaries allowing for the production of a microbeam for various applications. Experiments concerning electrons are presented showing that apart from being elastically scattered these negative particles may enter into the capillary surface where they suffer energy losses. Finally, theoretical concepts of the capillary guiding are discussed. Simulations based on different charge transport methods clearly support the understanding of the guiding mechanisms. Altogether, capillary guiding involves several novel phenomena for which understanding have progressed far beyond their infancy.
We demonstrate here that cold antihydrogen beams formed and extracted from a cusp magnet (anti-Helmholtz coils) are well focused and spin-polarized. A new discovery was the fact that the antihydrogen ...beam follows the well-known lens formula of optical lenses with its focal length properly scaled with the initial kinetic energy, the magnetic field strength and the magnetic moment. Furthermore, the simulation revealed that for a certain kinetic energy region of antihydrogen atoms, the optimum production position is upstream of the center of the cusp magnet, where a well-known nested potential configuration can be applied.
We publish three Roadmaps on photonic, electronic and atomic collision physics in order to celebrate the 60th anniversary of the ICPEAC conference. In Roadmap II we focus on electron and antimatter ...interactions. Modern theoretical and experimental approaches provide detailed insight into the many body quantum dynamics of leptonic collisions with targets of varying complexity ranging from neutral and charged atoms to large biomolecules and clusters. These developments have been driven by technological progress and by the needs of adjacent areas of science such as astrophysics, plasma physics and radiation biophysics. This Roadmap aims at looking back along the road, explaining the evolution of the field, and looking forward, collecting contributions from eighteen leading groups from the field.
In the 1980s, when the author worked for Seiko Epson Corporation as a wristwatch production engineer, consumer needs had become so diversified that wristwatches had to be assembled on the same ...automated assembly line in small lots of about 10,000 pieces per month. Most of the robots available in those days were for processing purposes such as spot welding and were not applicable in practical terms to automated assembly lines for wristwatches in precision, speed, ease of use or cost. The prototype SCARA robot developed by the SCARA Study Group led by Dr. Hiroshi Makino, a professor at the Department of Precision Engineering at Yamanashi University, was found to be the most suitable for automated watch assembly lines. We reviewed assembly work procedures and succeeded in limiting the number of simultaneous control axes to four at a maximum and in cutting assembly costs to 60% of those of conventional processing robots. As the term “selective compliance” suggests, SCARA robots possess all of the functions necessary for stable assembly and for precision and speed. Development team members, including the author, made the most use of previous experience in developing dedicated automated assembly machines for in-house use and succeeded in developing practical SCARA robots by creating a robot language based on workers’ voice. In applications of SCARA robots, this paper introduces just two of many possible examples. One is for oiling work on manual assembly lines and the other is the TAF-M mixed-models wristwatch assembly line. In the oiling work application example, SCARA robots used for infinitesimal oiling work on a manual assembly line for small lots of luxury wristwatches have been found to be very cost-effective and useful for training operators and/or programmers for robots. The TAFM application example represents the assembly line built based on the original Seiko-Epson purpose for introducing SCARA robot development, which consists of both robots and of 52 newly developed “assembly robot cells” where most assembly work should be done. An assembly robot cell includes a SCARA robot, a main conveyor, a multiple-parts feeder, an automatic hand changer, an assembly detection unit, etc. At present, one such assembly line automatically assembles more than 100 models of wristwatches. Use of such automated assembly lines has reduced the human workforce by about 40 workers, cut costs by over 60%, and shortened delivery time by about 50%.
We report the case of a 31-year-old man who was admitted with a 7-day history of cough and dyspnea and had a fever of 38.0°C the following day. He had taken antipyretics and lascufloxacin 75mg/day ...for 4 days, but his symptoms did not improve, and he was diagnosed as having mild COVID-19 and received home care. On the morning of the admission, he developed left scrotal pain and difficulty in walking, and visited our hospital. He had tenderness in the left epididymis and was diagnosed as having epididymitis associated with COVID-19, since no other cause of epididymitis could be identified. Chest CT revealed evidence of pneumonia, so that the patient was started on remdesivir. He had a fever of 37.9°C on day 1, but it resolved later and the respiratory symptoms improved. The left scrotal pain gradually resolved, and the patient was discharged on day 5. Semen analysis showed a low sperm count and motile sperm count on day 14. MRI showed enlargement and hyperintensity of the left epididymis. Although epididymitis is not usually associated with a reduction of the sperm count, COVID-19 infection affects the reproductive function, even in the absence of the symptoms of orchitis, because SARS-CoV-2 binds the angiotensin-converting enzyme 2 (ACE2) receptors in the testes and epididymises. A fertility test had been performed 2 months prior to the onset of COVID-19 in this patient, and it was possible to compare the semen findings before and after the infection.
Despite numerous reports that have linked diabetes with cognitive impairment (CI), there are few studies that have attempted to clarify the morbidity of CI among elderly diabetic patients. The ...Mini-Mental State Examination (MMSE) was performed on 240 diabetic patients aged 65 years or older who had no diagnosis of dementia. The MMSE scores were 28-30 (normal range) in 151 patients (63%), 24-27 (suspected CI) in 77 (32%), and ≤ 23 (definite CI) in 12 (5%). Eight of the 12 patients with MMSE scores ≤ 23 underwent further detailed examination: the final diagnosis was Alzheimer’s disease (AD) (N = 5), vascular dementia (N = 2), and mixed dementia (N = 1). Among 24 of the 77 patients with MMSE scores of 24-27 who were referred for further detailed examination, the final diagnosis was early AD (N = 5), cerebrovascular disease (CVD) (N = 10), and mild CI (N = 7). Only 2 of the patients were judged as being normal. The percentage of patients with a history of CVD, the rate of diuretic use, and the serum levels of non-high-density lipoprotein cholesterol were higher, and the percentage of patients with a history of habitual alcohol consumption was lower in the low MMSE score group than in the normal MMSE score group. Among elderly diabetic patients aged 65 years or older, 5% had evident CI and 32% had suspected CI. Medical staff involved in the care of diabetic patients should be highly aware of possible CI in this patient population.
We have developed a method to produce micro/nano meter sized beams of keV energy highly charged ions (HCIs) and MeV energy protons/He ions with tapered glass capillary optics for application of ...surface modifications and a biological tool called “cell surgery”, respectively. The transmission through the tapered glass capillaries with inlet diameter of 0.8
mmϕ, outlet diameter from 900
nmϕ to several tens of microns and length of about 50
mm was performed using 8/64
keV Ar
8+ beams. The transmitted beams had a density enhancement of about 10 and were guided through a capillary tilted by as large as ±100
mrad. The charge state of the beams was kept during the transmission. The combination of MeV proton/He ion beams and the capillary with a thin end window at its outlet can realize pinpoint energy deposition and three-dimensional selection of the bombarding point in an arbitrary position of a living cell or in any liquid object. We demonstrated that a real biological cell, HeLa cell with the nucleus labeled by green fluorescent protein (GFP), was irradiated with the microbeam, which was prepared by 4
MeV He
2+ entering a capillary with an end window of 7.3
μm in thickness and outlet diameter of 9.6
μmϕ. The transmitted MeV ion beams had density enhancement up to 1000 according to the capillary outlet sizes, which are applicable to various material analyses employing microbeams.
► Micro/nano meter sized ion beams are provided by tapered glass capillaries. ► Capillary’s inner radius was measured as a function of position along its axis. ► Density enhancement and guiding effect can be expected for keV ion beams. ► Combination of MeV ions and end windows has the possibility to realize cell surgery. ► Density enhancement of muon beams was also obtained by tapered insulator tubes.
We observed a slowly and regularly oscillating transmission current through a gap (0.1mm) of paired soda lime glass plates during an injection of a steady highly charged ion beam. The oscillation ...frequency was almost proportional to the injection current intensities. This phenomenon can be attributed to the charge–discharge iteration cycle with dynamic resistive switching of the glass plate. Our model calculation based on such cyclic resistive switching well reproduces the experimental observation.
An ion irradiation system in liquid has been developed using a tapered glass capillary with a thin window at the tip. Irradiation at a solid–liquid interface is interesting because it can be applied ...to novel analysis, radiation testing, and surface modification processes. In this study, polyethylene and polytetrafluoroethylene were irradiated with H
+ ions in an aqueous solution containing acrylic acid monomers. The irradiated surfaces which were originally hydrophobic became hydrophilic due to the surface layer formed by the acrylic acid polymer.
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