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The Fukushima Daiichi and Daini Nuclear Power Plant workers experienced multiple stressors as both victims and onsite workers after the 2011 Great East Japan Earthquake and subsequent nuclear accidents. Previous studies found that disaster-related exposures, including discrimination/slurs, were associated with their mental health. Their long-term impact has yet to be investigated.
A total of 968 plant workers (Daiichi, n = 571; Daini, n = 397) completed self-written questionnaires 2–3 months (time 1) and 14–15 months (time 2) after the disaster (response rate 55.0%). Sociodemographics, disaster-related experiences, and peritraumatic distress were assessed at time 1. At time 1 and time 2, general psychological distress (GPD) and post-traumatic stress response (PTSR) were measured, respectively, using the K6 scale and Impact of Event Scale Revised. We examined multivariate covariates of time 2 GPD and PTSR, adjusting for autocorrelations in the hierarchical multiple regression analyses.
Higher GPD at time 2 was predicted by higher GPD at time 1 (β = 0.491, p < 0.001) and discrimination/slurs experiences at time 1 (β = 0.065, p = 0.025, adjusted R2 = 0.24). Higher PTSR at time 2 was predicted with higher PTSR at time 1 (β = 0.548, p < 0.001), higher age (β = 0.085, p = 0.005), and discrimination/slurs experiences at time 1 (β = 0.079, p = 0.003, adjusted R2 = 0.36).
Higher GPD at time 2 was predicted by higher GPD and discrimination/slurs experience at time 1. Higher PTSR at time 2 was predicted by higher PTSR, higher age, and discrimination/slurs experience at time 1.
Using the IRAM 30 m telescope, we perform a molecular line survey of the 3 and 2 mm wavelength ranges towards 5 selected positions in the Galactic center region, sampling shocked regions, ultraviolet (UV) and X-ray pervaded regions, and positions with rich organic chemistry. These surveys have the potential to be used as chemical templates for different types of activity, such as photodissociated regions (PDRs), shocks and X-ray dominated regions (XDRs). Complementary, molecular surveys done towards extragalactic nuclei, that are also dominated by these physical activities, were carried by our group.
The seed consists of three distinct regions, the zygotic embryo and endosperm and the maternal seed coat. Development of the seed requires co-ordinated growth and differentiation within each of these regions. Although the major events that occur during seed development have been studied extensively at the anatomical, physiological and molecular level, a comprehensive understanding of gene activity in each seed region has been lacking. DNA microarrays and extensive sequencing of cDNA libraries permit genome-wide analyses of mRNA populations of biological samples. We review recent studies of genome-wide gene activity that illustrate approaches used to provide new insights into the processes that occur during seed development.
We have investigated the effect of polytype and oxidation condition on the temperature dependence of channel mobility and threshold voltage in 4H- and 6H-SiC MOSFETs. The behaviors of the channel mobility are apparently different for 4H- and 6H-SiC MOSFETs. In contrast to the polytype effect, dry and wet oxidation samples have almost similar channel mobilities. The variation of the threshold voltage with temperature is proportional to the number of the interface states near the conduction band extracted from n-type MOS capacitors. Therefore, we argue that the distribution of the interface states near the conduction band in p-type SiC MOS structure can be represented by that in n-type SiC MOS structure. Although the oxidation condition varies the distribution of the interface states in the energy range between 0.2 and 0.4 eV from the conduction band, it has little influence on the channel mobility.
Two types of shape and contrast features of superconducting vortices in a Lorentz micrograph were obtained by the newly developed 1-MV field-emission transmission electron microscope on a Bi2Sr2CaCu2O8+8(Bi-2212) thin specimen containing tilted columnar defects. The shape and contrast features could be consistently interpreted by the simulation that some vortices were pinned along tilted columnar defects and others were unpinned. The interesting property for temperature change of vortex core inside the material was also observed.
A single crystalline Bi2Sr2CaCu2O8+8 which has columnar defects in its inside are observed by Lorentz microscopy using the newly developed 1-MV field emission electron microscope at the first time. The superconducting vortices are observed with higher contrast than ever. Simultaneous observation of vortices and columnar defect is succeeded in real time.
The oxygen reduction reaction (ORR) mechanism of non-Pt catalysts was elucidated by investigating electronic structures of carbon alloy catalysts (CACs) for polymer electrolyte membrane fuel cells (PEMFC). For metal phthalocyanine-based carbon alloy catalysts with 1-2% of nitrogen and less than 0.1% of Co or Fe, photoelectron spectroscopy, X-ray absorption spectroscopy (XAS), and X-ray Absorption Fine Structure (XAFS) have revealed that Co or Fe metal sites are not the ORR active site, whereas the carbon atoms adjacent to graphitic nitrogens at a zigzag edge of graphite may act as the ORR active site, which is in good agreement with first principles calculations. These studies have also revealed that the zigzag edges, detected as a XAS shoulder component, are well evolved for catalysts pyrolyzed at 600°C, which show the maximum ORR activity. Based on these analyses, we have realized significantly improved carbon alloy based ORR performance, up to about 70 % of that with Pt catalysts. Further, to analyze the electronic structure of CACs during operation, we constructed a new in situ soft X-ray emission spectroscopy system with very high energy resolution (ΔE) of 120 meV at 640 eV at the University of Tokyo beamline BL07LSU in SPring-8.
Highly oriented YBCO films were produced on MgO(100) single crystal substrates. The direction of c axis was perpendicular to the film plane, whereas those of a and b axes were at random directions. The critical current density of the films was significantly high ca. 7x105 A/cm2. The critical transition temperature (Tc) of the YBCO film formed on a metal substrate, predeposited with YSZ as a buffer layer, was similar to those of the YBCO on MgO substrate. The possibility for the formation of superconductor films on metal substrates is suggested from these results.
The concentration and arrangement of Si vacancy in aluminum or phosphorus containing ReSi1.75 based silicides have been investigated. Both aluminum and phosphorus are substituted with silicon. In addition to the (001)C11b twins usually observed in binary ReSi1.75, planar defects are heterogeneously formed in both of the silicon substituted ternary alloys with small amount. By using the high resolution electron micrograph (HREM) technique, the planar defects are assigned as crystallographic shear (CS) planes lying on (109) C11b and (107) C11b in aluminum and phosphorus containing ReSi1.75, respectively. The CS vector in both ternary alloys is C11b. Since the concentration of vacancies in the ReSi1.75 structure is changed by the introduction of these crystallographic shear, ternary alloys with silicon substituted by aluminum and phosphorus contain more or less amount of vacancies than the binary alloy, respectively. This implies us that concentration of Si vacancies changes so as to retain the average number of valence electron. We can control the concentration of Si vacancy in the ReSi1.75 based alloys.
The dependences of dopant species and concentrations on the growth of oxide precipitates have been studied using transmission electron microscopy. Doping species are phosphorus, antimony and boron. Samples were annealed at 800°C and 850°C for 24∼384hr in dry nitrogen. In phosphorus-doped silicon, the precipitate density is independent of doping concentration and the growth of precipitate obeys the three-quarter power law. The enhancement of the precipitate growth is observed in antimony-doped silicon. On the other hand, the precipitate growth is suppressed in heavily boron-doped silicon as compared with that of lightly boron-doped silicon. This indicates the generation of excess silicon interstitials in heavily boron-doped silicon.
In dislocated Cz-Si crystals, rows of flow patterns (FP) and Secco etch pits (SEP) (2–3 mm in length, along <110> direction) can be revealed by Secco etch without agitation. In this study, the crystal defects forming FP-SEP rows in dislocated Cz-Si crystals are investigated by transmission electron microscopy. Microdefects, 0.1 μm in size, are observed in a row along a FP-SEP row, <110> direction. These defects were identified as oxygen precipitates with or without dislocation loops (interstitial-type), and voids with oxidized interiors. We conclude that FP originate from interstitial-type dislocation loops, and SEP are due to oxygen precipitates or voids.
Thermoelectric properties of a homologous series of Magnéli phase titanium oxides TinO2n-1 (n = 2, 3..) have been investigated. Dense polycrystalline specimens with nominal composition of TiO2-x (x = 0.10, 0.20) have been prepared by conventional hot-pressing. X-ray diffraction analysis has revealed that prepared specimens are slightly reduced during hot-pressing. Electrical conduction is of n-type for all prepared titanium oxides and electrical resistivity and absolute values of Seebeck coefficient decrease with increasing oxygen deficiency. The carrier concentration of Magnéli phase titanium oxide increases with increasing oxygen deficiency. Lattice thermal conductivity decreases with increasing oxygen deficiency by more than 60% at room temperature and 40% at 773K compared to TiO2, which can be due to the presence of dense planar defects. The largest thermoelectric figure of merit Z, 1.6×10-4 K-1 at 773K, was obtained in TiO1.90 hot pressed specimen.
We have fabricated top-gated field effect transistors (FETs) using graphene synthesized by chemical vapor deposition directly on a SiO2/Si substrate without using any transferring processes. Graphene was synthesized on an Fe catalyst film on the substrate at 650°C. The catalyst film was then etched after both ends of the graphene were fixed by source and drain electrodes, leaving the graphene channel connecting the two electrodes. Top-gated FETs were then made by covering graphene channels with HfO2 and depositing top electrodes. The drain current was successfully modulated by the gate voltage and exhibited the bipolar behavior that is characteristic of graphene. Also, it has been shown that graphene channels can sustain an electric current with a density of 107–108 /cm2. Our newly developed fabrication process paves a way to fabricate graphene transistors all over large substrates including Si and glass.
A cationic peptide dendrier, dendritic poly(L-lysine), forms complexes with oligonucleotides and can deliver them to liver after intravenous injection. Here, we tried to deliver apolipoprotein B-specific siRNA for the treatment of hypercholesterolemia and NFκB decoy for the hepatitis treatment. Significant therapeutic effects in those disease model mice were observed after intravenous injection of the oligonucleotides complexes with dendritic poly(L-lysine).
Guion, Clark, Harada and Wayland (2003) found that three factors affect English speakers' stress placement on bisyllabic non-words: syllabic structure, lexical class and stress patterns of phonologically similar real words. The current replication and extension included three groups (N = 30): native English speakers, early Spanish–English bilinguals, and late Spanish–English bilinguals. Participants produced and gave perceptual judgments on 40 non-words of varying syllabic structures in noun and verb sentence frames. A regression analysis used the three factors to predict stress placement in production and perception. All three groups showed significant effects from stress patterns of phonologically similar real words and lexical class. The effect of syllabic structure for early bilinguals was slightly different from that of native speakers and late bilinguals showed greatly reduced effects. Late bilinguals exhibited more initial stress overall, possibly due to L1 transfer. These results run counter to the prediction made by Long (1990) about age effects on phonological acquisition.