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This study examines the relationship between paternal height or body mass index (BMI) and birth weight of their offspring in a Japanese general population. The sample included 33,448 pregnant Japanese women and used fixed data, including maternal, paternal and infant characteristics, from the Japan Environment and Children’s Study (JECS), an ongoing nationwide birth cohort study. Relationships between paternal height or BMI and infant birth weight [i.e., small for gestational age (SGA) and large for gestational age (LGA)] were examined using a multinomial logistic regression model. Since fetal programming may be a sex-specific process, male and female infants were analyzed separately. Multivariate analysis showed that the higher the paternal height, the higher the odds of LGA and the lower the odds of SGA in both male and female infants. The effects of paternal BMI on the odds of both SGA and LGA in male infants were similar to those of paternal height; however, paternal height had a stronger impact than BMI on the odds of male LGA. In addition, paternal BMI showed no association with the odds of SGA and only a weak association with the odds of LGA in female infants. This cohort study showed that paternal height was associated with birth weight of their offspring and had stronger effects than paternal BMI, suggesting that the impact of paternal height on infant birth weight could be explained by genetic factors. The sex-dependent effect of paternal BMI on infant birth weight may be due to epigenetic effects.
This study evaluated the prognosis of idiopathic sudden sensorineural hearing loss when treated with hyperbaric oxygen therapy and intravenous steroids.
The clinical data for 334 patients with idiopathic sudden sensorineural hearing loss treated by hyperbaric oxygen therapy and intravenous steroids at our hospital were retrospectively reviewed. These data included the initial averaged five-frequency hearing level, patient age, interval between onset of symptoms and treatment, vertigo as a complication, and co-existence of diabetes mellitus.
The overall improvement rate was 69.2 per cent, including better improvement (25.5 per cent), good improvement (21.0 per cent) and fair improvement (22.7 per cent).
Hyperbaric oxygen therapy appears to confer a significant additional therapeutic benefit when used in combination with steroid therapy for idiopathic sudden sensorineural hearing loss. If performed early, hyperbaric oxygen therapy may bring about hearing improvement in many patients who are unresponsive to initial therapy.
Glacier surface mass-balance measurements on Greenland started more than a century ago, but no compilation exists of the observations from the ablation area of the ice sheet and local glaciers. Such data could be used in the evaluation of modelled surface mass balance, or to document changes in glacier melt independently from model output. Here, we present a comprehensive database of Greenland glacier surface mass-balance observations from the ablation area of the ice sheet and local glaciers. The database spans the 123 a from 1892 to 2015, contains a total of ~3000 measurements from 46 sites, and is openly accessible through the PROMICE web portal (http://www.promice.dk). For each measurement we provide X, Y and Z coordinates, starting and ending dates as well as quality flags. We give sources for each entry and for all metadata. Two thirds of the data were collected from grey literature and unpublished archive documents. Roughly 60% of the measurements were performed by the Geological Survey of Denmark and Greenland (GEUS, previously GGU). The data cover all regions of Greenland except for the southernmost part of the east coast, but also emphasize the importance of long-term time series of which there are only two exceeding 20 a. We use the data to analyse uncertainties in point measurements of surface mass balance, as well as to estimate surface mass-balance profiles for most regions of Greenland.
We carefully re-examine the evolution of small scale cosmological perturbations, motivated from the studies of cosmic structure formation in the high-z universe. Under the assumption of the hierarchical clustering scenario, the evolution of density fluctuations on very small scales is especially important for the early formation of the bound objects such as population III stars or primordial sub-galaxies.
There is limited information available regarding the benefits and outcomes of resection of pulmonary metastases arising from head and neck cancers.
A retrospective review was performed of 21 patients who underwent resection of pulmonary metastases of primary head and neck malignancies at Hamamatsu University Hospital. Clinical staging, treatment methods, pathological subtype (particularly squamous cell carcinoma), disease-free interval and overall survival were evaluated.
The 5- and 10-year overall survival rates of the study participants were 67.0 per cent and 55.0 per cent, respectively, as determined by the Kaplan–Meier method. The prognosis for patients with a disease-free interval of less than 24 months was poor compared to those with a disease-free interval of greater than 24 months (p = 0.0234).
Patients with short disease-free intervals, and possibly those who are older than 60 years, should be categorised as having severe disease. However, pulmonary metastases from head and neck malignancies are potentially curable by surgical resection.
A concentrated nuclear bulge with about 30% of the galaxy mass is sufficient (Lin, 1975; Berman and Mark, 1978) to eliminate strong bar-forming instabilities which dominate the dynamics of the stellar disk. Weak bar-like or oval distortions might remain depending on the model. In such systems self-excited discrete modes give rise to global spiral patterns which are maintained in the presence of differential rotation and dissipation (cf. especially the spiral patterns in Bertin et al., 1977, 1978). These spiral modes are standing waves that are physically analyzable (Mark, 1977) into a superposition of two travelling waves propagating in opposite directions back and forth between galactic central regions and corotation (a resonator). Only a few discrete pattern frequencies are allowed. An interpretation is that the central regions and corotation radius must be sufficiently far apart so that a Bohr-Sommerfeld type of phase-integral condition is satisfied for the wave system of each mode. The temporal growth of these modes is mostly due to an effect of Wave Amplification by Stimulated Emission (of Rotating Spirals, abbrev. WASERS, cf. Mark 1976) which occurs in the vicinity of corotation. In some galaxies one mode might be predominent while other galaxies could exhibit more complicated spiral structure because several modes are present. Weak barlike or oval distortions hardly interfere with the structure of these modes. But they might nevertheless contribute partially towards strengthening the growth of one mode relative to another, as well as affecting the kinematics of the gaseous component.
Studies of the stellar distribution in the inner region of our Galaxy have been seriously hampered at optical wavelengths by strong interstellar extinction. The extinction decreases considerably at infrared wavelengths, allowing us to look deep into the Galaxy. Motivated by this, we have tried to observe the near infrared brightness distribution of the central region of the Galaxy (Okuda et al., 1977, Maihara et al., 1978, Oda et al., 1978). Similar observations have been carried out by Hayakawa et al., (1976), Ito et al., (1977), and Hofmann et al., (1977). These observations have provided valuable information on the distributions of stars and dust in the inner Galaxy (Hayakawa et al., 1977, Maihara et al., 1978, Oda et al., 1978).
We analyze photoluminescence (PL) and electroluminescence (EL) using a hyperspectral imager that records spectrally resolved luminescence images of solar cell absorbers. The system is calibrated to yield the luminescence flux in absolute values. This system enables to quantitatively image physical parameters such as the photovoltage with an uncertainty of less than 30mV. The wide field illumination, low power excitation and fast acquisition brings new insights compared to classical setups such as confocal microscope. Several types of absorbers have been analyzed. For instance, we can investigate spatial fluctuations of the Quasi Fermi Levels splitting in CIGS polycristalline absorbers and link those fluctuations to transport properties. The method is general to the point that third generation PV cells absorbers can also be evaluated. We illustrate the great potential of our setup by imaging carrier temperature in Hot Carriers Solar cells absorbers and quasi Fermi levels splitting in Intermediate Band Solar cells.
In efforts to achieve higher efficiency of thin film Si solar cell, light trapping is one of the most important strategies in designing the cell structure. From the past studies, it is well known that TCO with a higher haze can exhibit better light trapping characteristics for a superstrate type thin film Si solar cell, while such TCO could give lower Voc and FF values caused by steep valleys in the texture of TCO. Furthermore, TCO with too high haze in a longer wavelength region could make back reflectance at the Ag rear electrode/reflector lower due to plasmonic effect on rough surface of Ag and thus reduces the efficiency of light trapping. In order to solve this contradictory behavior of light trapping in a conventional thin film Si solar cell, we have newly developed a glass-laminated module of thin film Si solar cell which has enhanced light trapping without deteriorating Voc nor high reflectance of Ag rear reflector.
NEWAGE is a direction-sensitive dark matter search experiment with a gaseous
time-projection chamber. We improved the direction-sensitive dark matter limits by our
underground measurement. In this paper, R&D activities sinse the first underground
measurement are described.
We present VLBI maps of the 6.7 GHz methanol maser emission in 32 sources obtained using the Japanese VLBI Network (JVN) and the East-Asian VLBI Network (EAVN). All of the observed sources provide new VLBI maps, and the spatial morphologies have been classified into five categories similar to the results obtained from European VLBI Network observations (Bartkiewicz et al. 2009). The 32 methanol sources are being monitored to measure the relative proper motions of the methanol maser spots.
Correlation between defect structures and light emission from Si-nanocrystal doped SiO2 films has been studied using electron spin resonance ( ESR ) and photoluminescence ( PL ) methods. The ESR analysis revealed the presence of three kinds of ESR centers in the film after annealing at above 900 °C in argon ( Ar ) atmosphere, i.e. Si dangling bond in amorphous Si cluster ( a-center: g=2.006 ), Si dangling bond at Si-nanocrystal/SiO2 interface ( Pb-center: g=2.003 ) and conduction electrons in Si-nanocrystal ( Pce-center: g=1.998 ). Moreover, visible light emission was observed in the annealed sample from the PL measurement. Both the PL intensity and the ESR signal intensity of the Pce-center were increased with an increase of annealing temperature. These results indicate that the Pce-center is strongly associated with the emission center.
Optical properties of fully-strained wurtzite and zincblende InxGa1-xN/GaN multiple quantum well (MQW) structures were compared to discuss the origin of exciton localization. In contrast to the hexagonal InGaN MQWs, the photoluminescence (PL) peak energy of cubic InGaN MQWs showed a moderate blueshift with decreasing well thickness, L, and low-temperature PL decay time of the cubic MQWs did not depend strongly on L. The results imply that the wavefunction overlap in cubic InGaN MQWs was not reduced compared to the hexagonal ones, since they do not suffer from the electric field normal to the QW plane due either to spontaneous or piezoelectric polarization. Both MQWs exhibited a large and composition-dependent bandgap bowing, and time-resolved PL (TR-PL) signals showed a stretched-exponential decay even at room temperature. The exciton localization is considered to be an intrinsic property of InGaN.
Magnetic tunnel junctions of Co0.9Fe0.1/SrTiO3 (STO)/ La0.7Sr0.3MnO3 (LSMO) with a spin-valve structure having an antiferromagnetic MnIr layer have been fabricated by sputtering. Junction magnetoresistance (MR) behavior and its dependence on the bias voltage are examined for junctions with epitaxial STO barrier formed under different sputtering conditions. Spin dependent transport measurements show that these junctions exhibit spin-valve type MR loops with an inverse (positive) MR of the ratio of 14-22 % at 4.2 K. The inverse MR observed is asymmetric with respect to the bias voltage direction. Stoichiometric STO barrier, as characterized by Rutherford backscattering (RBS) analysis, is found to result in very large asymmetric bias dependence, while the junctions with nonstoichiometric STO barrier exhibit the symmetric bias dependence. Our results suggest that the nonstoichiometry of STO barrier modifies the electronic structures of electrode/barrier interfaces, and thereby reducing the asymmetry of bias voltage dependence of junction MR.
Implantation of Mg+ and C+ ions is carried out in bulk InP substrates using single or several energies up to 400 keV. The net carrier concentration profile at 300K is measured by capacitance-voltage (C-V) method. The ground and excited states binding energies of Mg and C acceptors are determined by low-temperature selective excitation of photoluminescence (PL). Additional sharp exciton-Iike emissions are detected after annealing of the samples. Their intensity is found to decrease with increasing Mg+ or C+ dose. Annealing-induced activation and/or formation of complex defect are the likely candidate mechanisms for the involved defect.
CdTe-ZnTe strained-layer superlattices (SLSs) were used to reduce the density of threading dislocations in CdTe epilayers on GaAs substrates. Three types of SLSs were characterized by double-crystal X-ray rocking curves and transmission electron microscopy (TEM). The SLS blocked dislocations when the thickness of both the individual layers and the total SLS does not exceed the critical layer thicknesses. TEM images of both cross-section and plan-view show that the twothirds of the maximum number of threading dislocations were blocked by the SLS and, on average, half of these were blocked. While, in the other SLSs, new defects (threading dislocations and/or stacking faults) were generated in layers that exceeded the critical thickness. These defects offset the effect of any dislocation bending.
Electrical properties of heavily Be-doped GaAs grown by molecular beam epitaxy were investigated systematically in a wide range of Be-concentration from 1× 1014 up to 2× 1020 cm-3 by using yan der Pauw technique. Probable carrier scattering mechanisms observed in this work are discussed by taking into account the radiative mechanisms of several new photoluminescence emissions previously observed in the band-edge-emission region of the samples. All samples were checked their electrical properties first at room-temperature. Five selected samples out of them were measured from 10° K up to room-temperature. Samples having the carrier concentration from 1014 to 1018 cm3 presented typical semiconductor-like conduction with finite carrier excitation energy. For samples having carrier concentration 7× 1016 cm -3, the conduction mechanism at high temperature region above 30β K was dominated by holes thermally excited into valence band. At low temperature region below 30° K . it was dominated by holes hopping from neutral to ionized acceptors with the assistance of phonons. Hole mobilities of samples having the carrier concentration from 1017 to 1018 cm-3 showed an anomalous behavior in the low temperature region, which suggests the presence of a new type of carrier scattering mechanism. A radiative center denoted by lg-gl observed in this concentration region will be a candidate scattering center to explain these electrical behaviors. Samples having the carrier concentration larger than 1019 cm-3 demonstrated typically metallic electric conduction not owing to thermally excited carriers, which means that an impurity band is formed but merged with valence band. The density of state of this combined valence band mixed with impurity band can be supposed to reflect carrier concentration dependence of the PL emission bands observed in this region, i.e. [g-g]α , [g-g]β and [g-g]γ .
Silica based multi-component glass fibers were fabricated using core glass doped with erbium concentration in the range of 650 to 34000wtppm. The highest gain of 18dB was achieved at the Er3+ concentraion of 7000wtppm under pump wavelength and power of 1.48μm and 40mW, respectively. The gain decreased at concentration over 7000wtppm due to clustering of Er3+ ions. The increases in the threshold value of the pump power caused by clustering of Er3+ ions was also recognized.