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The coronavirus disease 2019 (COVID-19) vaccine may hold the key to ending the pandemic, but vaccine hesitancy is hindering the vaccination of healthcare personnel (HCP). We examined their perceptions of the COVID-19 vaccine and implemented an intervention to increase vaccination uptake.
Participants and setting:
Healthcare personnel at a 790-bed tertiary-care center in Tokyo, Japan.
A prevaccination questionnaire was administered to HCP to examine their perceptions of the COVID-19 vaccine. A multifaceted intervention was then implemented involving (1) distribution of informational leaflets to all HCP, (2) hospital-wide announcements encouraging vaccination, (3) a mandatory lecture, (4) an educational session about the vaccine for pregnant or breastfeeding HCP, and (5) allergy testing for HCP at risk of allergic reactions to the vaccine. A postvaccination survey was also performed.
Of 1,575 HCP eligible for enrollment, 1,224 (77.7%) responded to the questionnaire, 533 (43.5%) expressed willingness to be vaccinated, 593 (48.4%) were uncertain, and 98 (8.0%) expressed unwillingness to be vaccinated. The latter 2 groups were concerned about the vaccine’s safety rather than its efficacy. After the intervention, the overall vaccination rate reached 89.7% (1,413 of 1,575), and 88.9% (614 of 691) of the prevaccination survey respondents answered “unwilling” to or “unsure” about eventually receiving a vaccination. In the postvaccination questionnaire, factors contributing to increased COVID-19 vaccination included information and endorsement of vaccination at the medical center (274 of 1,037, 26.4%).
This multifaceted intervention increased COVID-19 vaccinations among HCP at a Japanese hospital. Frequent support and provision of information were crucial for increasing the vaccination rate and may be applicable to the general population as well.
Public health checkups are conducted on 3-year-old children in Japan. However, it is often difficult to detect or provide ongoing support to children with developmental disorders without MR. Therefore we have conducted health checkups on 5 year olds.
The objectives are to describe the results and follow-up of health checkups in 5-year-old children and examine the utility of such checkups.
The aims are to make clear the utility of health checkups in 5-year-old children for screening for developmental disorders.
The subjects were 303 children of 5-year-old that lived in Kanie-cho and participated in health checkups. in the checkups, a child psychiatrist examined the children, and made a provisional diagnosis of a developmental disorder.
Eighty-two children were provisionally diagnosed as having developmental disorders. the follow-up allowed final diagnosis of developmental disorders (suspect diagnosis included) to be made in 39 children (12.9%), and pinpointed 19 children with ADHD, 9 children with PDD, 9 children with mild MR, and 2 children with motor skills disorder.
All children with PDD had already been informed about the possible occurrence of developmental disorders at 3 years of age. However, most of ADHD, mild MR, and motor function disorder were diagnosed in these children during the checkups at the age of 5 years.
The health checkup in 5-year-old children is useful not only as a tool to detect developmental disorders that are difficult to diagnose at the age of 3 years but also as an approach in patients lost to follow-up.
For a formation of metal hydride of MgH2 or AlH3 under room temperature and ambient pressure, the cathode electrodes of metal and lithium hydride are electrochemically charged with Li anode electrodes in the system of Li-ion extraction. For MgH2 formation, the VC (Voltage-Composition) curve of Mg + 2LiH during charge shows a plateau voltage at 0.6 V until the final composition of 1.05 Li extraction. After charge MgH2 phase is observed by the XRD measurement. Therefore MgH2 is produced by the electrochemical charge from Mg and LiH. For AlH3 formation, Al + 3LiH is charged until the final composition of 0.6 Li at a plateau voltage of 0.8 V which corresponds to the reaction between Al and LiH for the formation of AlH3. In the XRD profile after charge AlH3 phase is not detected although the intensities of Al and LiH decrease compared with these before charge, which suggests the reaction leading to the formation of AlH3.
In-situ observation of the reaction between light weight hydride LiH and NH3 gas was performed by means of TEM (Transmission Electron Microscopy) with an environmental cell. This environmental cell was designed for the observation of the gas-solid reaction under 0 ∼ 0.2 MPa gas atmosphere at 20 ∼ 150 °C. It has been confirmed a volume expansion and generation of LiNH2, that is the reaction between LiH and NH3. Moreover, it was revealed that LiNH2 was generated at the surface of LiH particle at first process of the reactions.
We investigate the nonlinear behaviour of the dynamically unstable
rotating star for the bar mode by three dimensional hydrodynamics in
Newtonian gravity. We find that an oscillation along the rotation
axis is induced throughout the growth of the unstable bar mode, and
that its characteristic frequency is twice as that of the bar mode,
which oscillates mainly along the equatorial plane. The numerical
results also indicate that the vertical oscillation amplifies another
waves with odd azimuthal wave-numbers in the horizontal plane like
Faraday resonance. A possibility to observe Faraday resonance in
gravitational waves is demonstrated and discussed.
The mechanism of the fast reversible change between the amorphous and crystalline phases in (GeTe)1−x(Sb2Te3)x (GST) has not yet been fully understood. The crystalline phase has been identified as having a NaCl-type cubic structure with random occupation of the A sites by Ge, Sb and vacancies, and 100% occupation of B sites by Te. This fact calls our attention to a possible close relation to the inherent crystal bonding instability observed for the average five valence electrons (<5>) family. We present here the results of systematic hard X-ray photoemission experiments on GST films with various compositions in both the amorphous and crystalline phases, and discuss that a similar chemical bonding instability does indeed play an essential role in the phase change mechanism in GST. We propose a model for the fast phase change, in which 6 fold to 3 fold transition of p-like bonding play an essential role, in this class of materials.
Formation of interfacial dislocations (IDs) and dislocation half-loop arrays (HLAs) and their appearance in 4H-SiC epi-wafers are investigated by X-ray topography and KOH etching analysis. Synchrotron reflection X-ray topography demonstrates the ability to image IDs and HLAs simultaneously and reveal their densities as well as spatial distributions in the epi-wafers. The vertical location of IDs in the epi-wafer is also examined by this technique. The influence of wafer warp, in-situ H2 etching prior to epitaxial growth, substrate off-angle as well as the growth face (Si-face and C-face) on the densities and spatial distributions of IDs and HLAs are discussed.
Thin and continuous CVD Cu seed layer was successfully deposited on Ru under-layer by Cu oxide deposition and reduction method at 100°C with novel chemistry. Cu oxide was formed with Cu(hface)TMVS and H2O2 at 100°C, and this film was reduced with formic acid at 100°C. Deposited Cu oxide films were Cu2O that was confirmed by XRD and XPS. The morphology of oxide films showed smooth and continuous on Ru and Ta substrate. The reduced Cu film on Ru maintained good surface morphology, and no impurity was detected not only in the Cu film but also the interface between Cu and Ru. However, that on Ta had poor morphology by agglomeration of Cu film during reduction due to poor Cu wettability on oxidized Ta that was oxidized during oxide deposition. The readiness of reduction is very important merit of using Ru under-layer for this oxide deposition and reduction process. The oxide deposition and reduction method on Ru under-layer can be a promising candidate for thin and continuous seed layer deposition method.
Fine grained gamma+beta dual phase microstructures were obtained in aluminum-titanium-vanadium ternary alloys containing 40 at.% aluminum and 60 at.% (titanium and vanadium). Average grain size was about 5, 3, and 2 micrometers in the recrystallized materials containing 20, 30, and 40 at.% vanadium, and the phase constitution was around 50vol.% gamma phase and 50vol.% beta phase. Compression behavior was investigated at temperatures ranging from the room temperature up to 1200K, and compressive creep tests were carried out at 1050-1200K in order to characterize the temperature and chemical composition dependences of strength and deformation. These gamma+beta microduplex materials showed very high strength at room temperature; 0.2% proof stress was around 1200MPa. The compression deformability decreased from about 0.2 to 0.05 true strain with increasing vanadium content. The grain size effect was not clarified yet, but it was rather disappointing that smaller-grained material with Al40Ti20V40 composition did not show effective improvement either in strength or in deformability. 0.2% proof stress showed a considerable weakening at temperatures higher than 900K; the onset temperature of softening became lower as the vanadium content increased. In Al40Ti40V20 material with about 5 micrometer grains, both gamma and beta grains were flattened up to 1000K, however, above 1100K the gamma grain showed no significant shape change even after a heavy deformation. This is probably because the gamma grains were relatively stronger than the beta grains. The gamma grains showed tendency toward agglomeration, which is similar to rafting of precipitate particles. Surface relief was observed after high temperature deformation suggesting activity of boundary sliding on grain boundaries and interfaces. Compressive creep behavior was investigated under a constant true stress in vacuum. Creep curves consisted of a small amount of normal primary transient, the minimum creep rate region, and a steady or slightly accelerating creep region. Stress exponent decreased to about 2 with decreasing vanadium content. It was rather unexpected that smaller grained Al40Ti20V40 material showed larger stress exponent around 3.
Brillouin and Raman spectra of a 0.71Pb(Ni1/3Nb2/3)O3-0.29PbTiO3 single crystal were measured in two light scattering geometries to elucidate the origins of central peaks that is related to the dynamics of the polar nanoregions. Two Lorentzian-type central peaks exist in the Brillouin spectra. The shape and the full width at half maximum of the broader peak in Brillouin spectra are almost same as that observed in Raman spectra. This indicates that two relaxations occur in the polar nanoregions. These two processes might be originated from the different switching directions of polarization.
A recently developed bidirectional thermal expansion measurement (BTEM) method was applied to different types of low-k films to substantiate the reliability of the Poisson's ratio found with this technique and thereby to corroborate its practical utility. In this work, the Poisson's ratio was determined by obtaining the temperature gradient of the biaxial thermal stress from substrate curvature measurements, the temperature gradient of the whole thermal expansion strain along the film thickness from x-ray reflectivity (XRR) measurements, and reduced modulus of the film from nanoindentation measurements. For silicon oxide-based SiOC film having a thickness of 382.5 nm, the Poisson's ratio, Young's modulus and thermal extension coefficient (TEC) were determined to be Vf = 0.26, αf =21 ppm/K and Ef =9,7 GPa. These data are close to the levels of metals and polymers rather than the levels of fused silicon oxide, which is characterized by Vf = 0.17 and Er = 69.6 GPa. The alkyl component in the silicon oxide-based framework is thought to act as an agent in reducing the modulus and elevating the Poisson's ratio in SiOC low-k materials. In the case of an organic polymer SiLK film with a thickness of 501.5 nm, the Poisson's ratio, Young's modulus and TEC were determined to be Vf = 0.39, αf =74 ppm/K and Er =3.1 GPa, which are in the typical range of V= 0.34~0.47 with E =1.0~10 GPa for polymer materials. From the viewpoint of the relationship between the Poisson's ratio and Young's modulus as classified by different material types, the Poisson's ratios found for the silicon oxide-based SiOC and organic SiLK films are reasonable values, thereby confirming that BTEM is a reliable and effective method for evaluating the Poisson's ratio of thin films.
The effective hydrogen capacity of TixCr2-yMny [≫X λ1.1 (1.08≤0x≤1.16), y λ1.0 (0.96≤y≤1.08)rsqb; exhibited the maximum value of 1.8 wt% in the pressure range of 33 MPa and 0.1 MPa at 296K (dissociation pressure: 5-11 MPa), and the alloy provided over 10% more capacity than conventional Ti-Cr-Mn (Ti1.2CrMn: 1.6 wt%, Ti1.2Cr1.9Mn0.1: 1.3 wt%). At the low temperature of 233 K, the alloy absorbed 2.0 wt% of hydrogen and the hydrogen desorption capacity at 0.1 MPa was 1.6 wt%. The dissociation pressure decreased with the Ti and the Mn contents and was explained by the function of the bulk modulus and the cell volume. According to the van't Hoff plots, the standard enthalpy differences (heat of formation) of the Ti1.16Cr0.92Mn1.08 and Ti1.08Cr1.04Mn0.96 hydrides were -21 and -22 kJ/molH2, respectively. These absolute values were about 10 kJ/molH2 smaller than those of LaNi5 and Ti-Cr-V. The alloy had sufficient hydriding and dehydriding kinetics. In the pressure range of 33 MPa and 0.1 MPa at 296 K, the alloy absorbed and desorbed 1.8 wt% of hydrogen in 60 sec and 300 sec, respectively. The hydrogen capacity changed gradually over many cycles and that after 1000 cycles was 94 % of the initial capacity. Thus Ti1.1CrMn can be utilized for a high- pressure MH tank which contains a hydrogen absorbing alloy with high dissociation pressure and compressed hydrogen.
A high-temperature nanoindentation measurement method has been developed for evaluating the hardness and modulus of low-k films when the temperature is raised from R.T. to 200°C. Thermal stability and chemical changes due to heating were investigated by Raman spectroscopy, Fourier transform infrared spectroscopy and thermogravimetry-differential thermal analysis, and by thermal desorption spectroscopy, respectively. Two different classes of low-k materials, organic polyarylence ether film and methyl-hydrogen-silsesquioxane film, were examined. The hardness and modulus of the former film during heating increased due to water desorption in the lower temperature range, and then decreased due to the evolution of hydrocarbon gas from some unreacted components or solvent residuals in the higher temperature range. In regard to the latter film, the hardness and modulus of a specimen (A) having a higher hydrocarbon content decreased during heating and reached the lowest value at 200°C and then constantly remained at the lowest levels during cooling. In contrast, no significant changes in hardness and modulus were observed for a specimen (B) having a lower hydrocarbon content in either the heating or cooling process. The reduction of the hardness and modulus of specimen A was attributed to thermal decomposition of most of its Si-CH3 and SiH/SiH2 chains. These results revealed that the temperature dependence of the hardness and modulus of low-k films is significantly affected by physical and/or chemical changes during heating due to moisture absorption, thermal evolution of organic residuals and thermal decomposition, rather than other factors such as thermal stress.
Larvae of the hydrothermal vent barnacle Neoverruca sp. were reared under laboratory conditions and larval development was observed. Under these conditions, the larvae were released from adults as first-stage nauplii, although the larvae of other deep-sea barnacles have generally been considered to be released at a later larval stage such as the cyprid stage. The larvae of Neoverruca sp. were lecithotrophic through six naupliar stages and the subsequent cyprid stage. The larval period of Neoverruca sp. was more than 96 days under the present rearing conditions, which is the longest yet reported for barnacles. Most cyprid larvae, however, exhibited abnormal morphology and no larvae settled successfully on the substrate. These observations suggest that such a long larval period might enable neoverrucid barnacles to disperse between vent fields.
It is shown that the periodic stacked structures of nanocrystalline porous silicon (nc-PS) layers with controlled densities and elastic properties act as an acoustic band crystal (ABC) device. Supposing that the periodic nc-PS layers are formed by conventional modulated anodization technique to fabricate the multi-layered distributed Brag reflection mirror, the acoustic wave propagation modes are investigated theoretically for various structural parameters. According to the calculation results, a significant acoustic band gaps are generated in the ultrasonic regions due to a big contrast in the elastic constant produced between low-porosity and compact nc-PS layers. The propagation of acoustic wave can be completely suppressed in the characteristic band determined from designed parameters. The present result suggests further possibility of the nc-PS layer as a key component of ABC devices.
Mechanism of electron transport through planerized nanocrystalline-Si (nc-Si) cold cathode surface emitting devices was investigated. The energy distribution of electrons emitted from nc-Si emitter was obviously not Maxwellian, which was usually obtained at conventional cold cathode devices, but was similar to that from the nanocrystalline porous silicon diode emitter. These results strongly suggest that electrons are emitted quasiballistically from our devices and indicate that the planarized nc-Si layer play an important role in this high efficiency cold cathode emitter.
Silicone oil was photo-chemically oxidized to change into SiO2 on the crystal by using an ArF excimer laser; the protective moistureproof film has been developed for a nonlinear optical crystal that is deliquescent.
The nonlinear optical crystals such as CsLiB6O10 (CLBO) and KH2PO4 (KDP) are deliquescent, which causes their surfaces to be cloudy by absorbing moisture in the air. We, therefore, demonstrated the growth of the SiO 2 film directly on the crystal so as to be moistureproof.
Firstly, dimethylsiloxane silicone oil (-O-Si(CH3)2-O-)n was poured on the substrate and coated by a spinner for making the silicone oil thin layer. Then, the ArF excimer laser was vertically irradiated on the sample in oxygen atmosphere. The O atom on the substrate surface was photo-excited by the laser to generate a high active O atom. At the same time, the Si-CH3 bond of the silicone oil was photo-dissociated and the dangling bond of Si was linked with the active O atom to form a SiO 2 film on the crystal surface.
In short, the film formed by the new technology can be used as a protective coating, which has the moisture resistance and the UV permeability, for a nonlinear optical crystal.