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Sleep disturbance is a common symptom in elderly people. However, the associated risk factors have not been completely clarified. We examined possible risk factors associated with sleep disturbance in a community-based Japanese cohort study.
1521 community-dwelling individuals aged 65 years or older were selected from a consecutive series at a cohort study from 2016 to 2018 in Arao city, where located at south part of Japan. In this survey, the clinical valuables were collected as follows: age, sex, occupational status, education, lifestyle information, medical history, EuroQoL(EQ)-5D (a score of health-related quality of life [QOL]), Barthel index (a score of performance in activities of daily living), a score of Geriatric Depression Scale (GDS) and a score of Mini-Mental State Examination (MMSE). Sleep disturbance was assessed by the Pittsburgh Sleep Quality Index (when the global score was 6 or over, sleep disturbance was determined to be present). Multiple logistic regression analysis was used to examine the association between clinical valuables and sleep disturbance. This research was supported by AMED (Japan Agency for Medical Research and Development) under Grant Number JP18dk0207025h0003 and has been approved by the research ethics committee of Kumamoto University. Informed consent was obtained from all participants and their family members.
Multiple logistic regression analysis revealed that Parkinson disease (Odds ratio[OR]=5.59), living alone (OR=1.93), liver disease (OR=1.89), hyperlipidemia (OR=1.36), higher score of GDS (OR=1.14), lower scores of both EQ-5D index (OR=1.11) and Barthel index (OR=1.03) were significantly associated as risk factors with sleep disturbance. Unexpectedly, lower score of MMSE was not a significant risk factor.
These results suggest that several physical illnesses, solitude, depressive symptoms and lower QOL, but not cognitive impairment, might be crucial risk factors associated with sleep disturbance in elderly population.
This paper presents an intelligent robot vision system using TOSPIX which has been newly developed to realize frequently-used and time-consuming image processing functions at low-cost and high-speed. The vision system has been studied for use in observing surface information about electric parts (dry batteries), inspecting them and then placing good ones into a given box. Three major robot vision functions are implemented here: object recognition, inspection and position determination by binary and gray-scale image processing techniques. While binary image techniques are used in battery terminal inspection and box position determination gray-scale image processing functions are performed in a label pattern check on a battery surface, front or rear surface determination, and surface defect inspection.
Nb-Ti-Ni alloy is one of the candidates for hydrogen permeation membranes. The hydrogen permeability of a membrane depends on its thickness, and mechanical properties such as the fracture toughness of the membrane are important to ensure reliability and durability. In the present work, micro-mechanical tests have been carried out for melt-spun Nb-Ti-Ni thin films consisting of amorphous and nano-crystalline phases. The relationship between the mechanical properties of the melt-spun films and the microstructural changes occurring in the films due to heat treatment has been also discussed. The Nb-Ti-Ni alloy thin films were prepared by the melt-spun technique and then heat-treated at 873-1173 K. Micro-sized cantilever specimens with dimensions of 10 × 10 × 50 μm3 were prepared by focused ion beam (FIB) machining. Fracture tests were carried out using a mechanical testing machine for the micro-sized specimens; the testing machine was developed by us. In addition, microstructures were observed by transmission electron microscopy (TEM). The fracture toughness (KQ) value decreased up to 823 K, and it increased above 1173 K. The specimen heat-treated above 1173 K showed ductile fracture. The fracture morphology of the specimen heat-treated up to 1023 K showed grain boundary fracture characteristics, and that of the specimen heat-treated at 1173 K changed to transgranular fracture.
Epitaxaially-grown KNbO3 thick films over 8 μm in thickness were successfully grown at 220 °C for 6 h on (100)cSrRuO3//SrTiO3 substrates by a hydrothermal method. Epitaxial SrRuO3 layers grown on (100)cSrTiO3 substrates by sputter method were used as bottom electrode layers. Relative dielectric constant and the dielectric loss were 530 and 0.11, respectively. Clear hysteresis loops originated to the ferreoelectricity were observed and a remanent polarization was 25 μC/cm2 at a maximum applied electric field of 540 kV/cm. In addition, the hydrothermal KNbO3 thick film was able to transmitting and receiving of ultrasonic waves over 50MHz.
We have studied on hydro-thermally synthesis of Pb(Ti, Zr)O3(PZT)piezoelectric polycrystalline thick film on titanium (Ti) substrate. The purpose of this study is resolving the problems for application of PZT hydrothermal polycrystalline thick film to the ultra miniature high frequency medical ultrasound array probe. The problems were the existence of pinholes in the deposited PZT film, the rough surface of that, low dielectric breakdown electric field etc. The surface of Ti substrate was pretreated to have hydrophilic property by using high reactivity of hydrogen peroxide for resolving the problems in this study. As results, hydrophilic property on the surface of Ti substrate was improved. Surface of PZT hydrothermal polycrystalline thick film without pinholes and smooth surface of that were obtained. Furthermore, the material properties like density, Young's modulus and piezoelectric constant d31 were increased by the pretreatment of Ti substrate. Consequently, dielectric breakdown electric field of PZT hydrothermal polycrystalline film was improved.
The purpose of this study was to improve deposition rate of the hydrothermal method for lead zirconate titanate (PZT) thick film on titanium substrate. We developed a high-speed rotaion substrate holder at a tangential velocity of about 0.8m/s in autoclave. A titanium substrate was fixed by the holder on the surface of a stirring bar. For the film deposition, powder of TiO2 was used instead of the liquid TiCl4. The deposition rate on titanium substrate was improved up to 7μm/24h. Piezoelectric constant d31 of the hydrothermal PZT film was -2.6 × 1011 V/m. This result was lower than that of PZT ceramics. However, this hydrothermal method obtained thick film and this film was confirmed to be polycrystalline PZT analyses of XRD and SEM. In addition, performance of thickness mode vibration of hydrothermal PZT 50μm thick film was investigated by radiating in water. The phase velocity of dilatational wave of the thickness mode vibration of the hydrothermal PZT film was 1800m/s and the electromechanical coupling factor was 47%.
A nongraphitizable carbon prepared from the cross-linked petroleum pitch and carbonized at 1473 K was found to have a unique structure and a charge capacity of more than 600 Ah/kg. A main peak of the 7Li Nuclear Magnetic Resonance spectra of the charged carbon shifted downfield with an increase of charge capacity. A Knight shift of lithium in the carbon charged to 600 Ah/kg reached 110 ppm when LiCl was used as the reference of 0 ppm. This shift was clearly distinguished from that of the lithium state in the first stage of the graphite intercalation compound, because the latter was observed at 45 ppm. A modified extended Hükel molecular orbital calculation showed that the average net electron density on lithium atoms drastically increased with increasing concentration of lithium atoms if the aromatic molecular planes are more than 0.5 nm apart. Both the experimental and theoretical results suggest that lithium atoms form clusters in this nongraphitizable carbon.