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Pneumococcal serotype replacement is an important issue after the introduction of pneumococcal conjugate vaccine (PCV) in children. After the introduction of 13-valent PCV, the incidence of invasive pneumococcal diseases (IPD) caused by Streptococcus pneumoniae serotype 12F (Sp12F) have increased in some countries; however, an outbreak of Sp12F has not reported in the post-13-valent PCV era. We experienced a local outbreak of Sp12F during March through May 2016 in Tsuruoka city, Japan after the introduction of 13-valent PCV in 2013. The IPD patients were two children and seven adults, three of whom died with a rapid disease progress. Although the clear transmission route was not determined, eight of the nine patients (89%) had close contact with children, which suggests that transmitted colonisation of Sp12F among children and adults might be the source of transmission. Continuous monitoring of IPDs, along with the determination of pneumococcal serotypes, is warranted in the post–13-valent PCV era. New IPD control strategies may be needed if this fatal outbreak continues to occur.
We present here the fundamental idea of the conversion method between old and new reference frameworks. Some practical applications are made for the optical observations for Tokyo PZT. The method can be also applied to the conversion of radio sources where we have met a great difficulty in performing the conversion because of no citation of observation epochs in general. We discuss their necessity in order to establish a concrete compilation of the position of the radio sources.
We are currently conducting three kinds of IR surveys of star forming regions (SFRs) in order to seek for very low-mass young stellar populations. First is a deep JHKs-bands (simultaneous) survey with the SIRIUS camera on the IRSF 1.4m or the UH 2.2m telescopes. Second is a very deep JHKs survey with the CISCO IR camera on the Subaru 8.2m telescope. Third is a high resolution companion search around nearby YSOs with the CIAO adaptive optics coronagraph IR camera on the Subaru. In this contribution, we describe our SIRIUS camera and present preliminary results of the ongoing surveys with this new instrument.
Four working groups and three task groups of IAU Commission 5 deal specifically with information handling, technical aspects of collection, archiving, storage and dissemination of data, with designations and classification of astronomical objects, with library services, editorial policies, computer communications, ad hoc methodologies, and with various standards, reference frames etc. Information about Commission 5 working and task groups and their activities may be found in http://nut.inasan.rssi.ru/IAU/.
A high time- and spatial-resolution radio interferometer for solar observations has been constructed at Nobeyama (Figure I.; Nakajima et al. 1994). The Nobeyama Radioheliograph consists of 84 antennas, 0.8m in diameter, arranged on a T-shape lines of 500m in the EW and 220m in the NS directions. The time resolution is 50 ms and the spatial resolution is 10”. The field of view is 40’ at the observing frequency 17GHz, which enables us to watch the whole sun. The radioheliograph has observed hundreds of flares during the few months since the beginning of regular observations in July ‘92, and such powerful performance has never before been demonstrated in the history of solar radio observations.
A high performance VLBI recorder project using advanced digital technology started in 1995. TOSHIBA GBR 1000 and VLBI interface define 32 parallel, 32 MHz clock standard digital interface and support transparent recording/play-back to extremely high-speed digital bit stream. This is the formatter independent scientific recording bind the UTC to observed data. This highly reliable, low-bit-error-rate (10−16) recording system is also expected to be used in other scientific field. For the first example to examine the recorder performance in VLBI, we had been prepared 1024 Mbps sampler (256/512/1024 MSps, 2 bit, 4/2/1 ch). And here, an experimental giga-bit correlator specification for these VLBI acquisition system is introduced.
Organic thin-film transistors (OTFTs) are the most promising candidates for flexible electronics owing to their flexible structures, the simplicity of processing large-area devices, and excellent compatibility with flexible substrates. To date, many studies have been reported that have aimed at developing a wide range of plastic electronics such as flexible displays, sensors. In this paper, we discuss our recent work, focusing on OTFT arrays and their application to flexible display. An active-matrix (AM) backplane using a low-temperature cross-linkable olefin-type polymer as the gatedielectric and an air-stable DNTT as the organic semiconductor (OSC) was successfully fabricated on a plastic substrate. The short-channel TFT array exhibited a high hole mobility of over 0.5 cm2/Vs, a low subthreshold slope of 0.31, and excellent environmental and operational stability. A 5-inch flexible OLED display exhibited a high luminescence of over 300 cd/m2 by driving of the DNTT-based OTFTs. Solution-processed OTFTs are also attracting considerable attention owing to both their simple manufacturing process and excellent transistor performance. We present a simple patterning process for a solution-processable OSC that can be used to develop a high-mobility short-channel TFT array. The OSC film was directly patterned on the confined active channel region by a simple lamination coating technique and the resulting TFTs showed a high mobility of up to 1.3 cm2/Vs. In the final section, we report on eco-friendly paper-based organic TFT array. A transparent cellulose nanofibers paper was firstly applied to a flexible substrate for the TFT backplane. A solution-processed TFT on the transparent paper exhibited a high mobility exceeding 1 cm2/Vs, good air stability, and excellent mechanical stability.
We have investigated the polycrystalline growth by means of an excimer laser assisted metal organic deposition process and the strategy for the efficient growth. It was revealed that the pulsed photo thermal heating properties must be controlled by changing the laser fluence according to the substrate properties, such as thermal diffusivity. The threshold of the teff value for initial crystal nucleation is approximately 70 ns for oxide thin films. For the fabrication of good quality films with high crystallinity and without a laser ablation of the film surface, it is necessary that the irradiated laser fluence is adjusted to the conditions of teff (efficient annealing time) > 70 ns and Tmax (maximum temperature) < Tm (melting point). Obtained oxide films by using the pulsed UV laser has large crystallite size, and it well functioned to enhance physical properties of films. For further efficient growth for polycrystalline growth of the oxide films, the starting solution containing nanoparticles is very useful: it is named as photo-reaction of nanoparticles process.
Ionization-induced injection into a laser-driven wakefield is studied using 2½D OSIRIS simulations. A laser propagates into a gas mixture of 99.5% helium and 0.5% nitrogen with gas density of each rising linearly from 0 to a peak, after which these remain constant. Simulations show that the process can be controlled by varying the scale length of an up-ramp, the laser intensity, and the maximum plasma density. The injection process is controlled by the bubble radius decreasing as laser propagates up the density gradient and laser self-focusing in the flat-top region. A beam with a central energy of 350 MeV and an energy spread (FWHM) of 1.62% was obtained for an up-ramp length of 135 μm, a normalized vector potential of 2, and a density of 7 × 1018cm−3 (assuming a 0.8 μm wavelength laser).
It is demonstrated that luminescent porous silicon (PS) exhibits an efficient thermoacoustic effect owing to its extremely low thermal conductivity. The experimental device is composed of a patterned thin Al film electrode (30 nm thick), a microporous PS layer (10–50 μm thick), and a single-crystalline Si (c-Si) wafer. The PS layer was formed by a conventional anodization technique. When an electrical input is provided to the Al electrode as a sinusoidal current followed by Joule's heating, a significant acoustic pressure is produced in front of the device as a result of an efficient heat exchange between PS and air. The output amplitude is in inverse proportion to the square root of the input frequency (0.1-100 kHz) as predicted by a theoretical analysis. The observed effect is a novel useful function of PS as a completely depleted nanocrystalline system.
The material properties of two ultra low-k organic polymers are characterized for copper interconnect integration. The k-values are 2.2-2.3 for both. Compared to OSG materials of similar k-values, these polymers have lower porosity and smaller pore size, achieved using selfassembled chemistry. Both materials demonstrate excellent resistance to plasma damage: no water uptake was detected after exposure to selected etching plasmas. This characteristic, combined with the small pore size and low porosity, results in the successful integration of the organic low-ks in 80 nm spacing with no significant increase in the integrated k-values.
It is found that higher open porosity in polymer A is accompanied by higher leakage current, which is not however linked to lower dielectric breakdown lifetimes.
In this paper, we first propose an improved CVD-WSix metal gate suitable for use with nMOSFETs. Work function of CVD-WSi3.9 gate estimated from C-V measurements was 4.3eV. The nMOSFET using CVD-WSi3.9 gate electrode showed that Vth variation of L/W=1 μm/10μm nMOSFETs can be suppressed to be lower than 8mV in 22chip. In CVD-WSi3.9 gate MOSFETs with gate length of 50nm, a drive current of 636μA/μm was achieved for off-state leakage current of 35nA/μm at 1.0V of power supply voltage. By using CVD-WSi3.9 gate electrode, highly reliable metal gate nMOSFETs can be realized.
The safe disposal of radioactive nuclear wastes using multi-barrier systems requires a good understanding of their transport properties in geological materials. When groundwater flow is very slow, the most important mechanisms of transport and retardation are diffusion through and sorption onto geological materials, and an evaluation of relevant parameters, particularly the effective diffusion coefficient and rock capacity factor (or sorption coefficient), is of fundamental importance to any safety assessment. Although laboratory diffusion tests can be used to determine these two parameters, conventional through-diffusion testing has some limitations, such as the need for a relatively long test time, cumbersome test procedures and the possibility of errors due to differences between analytical assumptions and actual test conditions. In this paper, we offer a rigorous solution to the through-diffusion test. Boundary conditions are improved by taking into account concentration changes in both the source and the measurement cells. A companion approach for back-calculating the effective diffusion coefficient and rock capacity factor is also proposed. The effectiveness and advantages of this improved technique are demonstrated using experimental data derived from a sedimentary rock sample taken from a research site in Japan.
The deposition process of epitaxial layers is simulated by the method of molecular dynamics. The interaction forces between atoms are calculated using the Stillinger-Weber potential. Before the deposition of atoms, the substrate is equilibrated at a specified temperature. Atoms with identical initial velocities and with initial coordinates selected at random in the plane parallel to the growth surface arrive at the substrate to form an overlayer. During the deposition, the lower part of the substrate is held at an initially specified temperature by velocity scaling. How the growth morphology of an overlayer is influenced by the substrate temperature is investigated in connection with the behavior of deposited atoms.
An amino functional group was substituted on a PET film surface for the purpose of making the implantation of collagen readily. The PET has been widely used for medical materials such as an artificial ligament because of its strength and antibacterial action. However, when transplanted in human bodies, its compatibility is not good enough to adapt to the collagen which grows from living body tissues. To avoid this reaction medicine has been used clinically which makes the PET fiber into a mesh state and after the transplantation into a human body, makes the tissue intrude in the PET fiber. However, this method has not shown satisfactory enough results to promote rehabilitation. If the living body compatibility of materials is improved the initial adapting power with the tissue can be enhanced.
Then we substituted NH2, which has a high affinity for collagen, on the PET surface by ArF laser. PET is highly hydrophobic and does not dissolve well in aqueous solutions. To avoid this reaction we make a thin ammonium fluoride solution layer on the PET surface with capillary phenomenon. Then an ArF laser beam was irradiated vertically onto the sample. The result of this treatment shows that an untreated sample having the contact angle of 80° with water and the bonding strength of only 1.0 kg/cm2 with collagen was improved to have the contact angle of 22° and the bonding strength to be 12 kg/cm2.
When the treated sample had been implanted into the subcutaneous tissue of a rabbit's regiones dorsales, existence of leukocyte colonies that are indicators of human histocompatibility was confirmed on the hydrophilic parts of the sample.