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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.
There seems to be magnetic fields at all scales and epochs in our Universe, but their origin at large scales remains an important open question of cosmology. In this work we focus on the generation of magnetic fields in the intergalactic medium due to the photoionizations by the first galaxies, all along the Epoch of Reionization. Based on previous studies which considered only isolated sources, we develop an analytical model to estimate the mean magnetic energy density accumulated in the Universe by this process. In our model, without considering any amplification process, the Universe is globally magnetized by this mechanism to the order of, at least, several 10−18 G during the Epoch of Reionization (i.e. a few 10−20 G comoving).
We initiated a long-term and highly frequent monitoring project toward 442 methanol masers at 6.7 GHz (Dec >−30 deg) using the Hitachi 32-m radio telescope in December 2012. The observations have been carried out daily, monitoring a spectrum of each source with intervals of 9–10 days. In September 2015, the number of the target sources and intervals were redesigned into 143 and 4–5 days, respectively. This monitoring provides us complete information on how many sources show periodic flux variations in high-mass star-forming regions, which have been detected in 20 sources with periods of 29.5–668 days so far (e.g., Goedhart et al. 2004). We have already obtained new detections of periodic flux variations in 31 methanol sources with periods of 22–409 days. These periodic flux variations must be a unique tool to investigate high-mass protostars themselves and their circumstellar structure on a very tiny spatial scale of 0.1–1 au.
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.
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.
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.
The correlation of stress in Silicon Carbide (SiC) crystal and frequency shift in micro- Raman spectroscopy was determined by an experimental method. We applied uniaxial stress to 4H- and 6H-SiC single crystal square bar specimen shaped with (0001) and (11-20) faces by four point bending test, under measuring the frequency shift in micro-Raman spectroscopy. The results revealed that the linearity coefficients between stress and Raman shift were -1.96 cm-1/GPa for FTO(2/4)E2 on 4H-SiC (0001) face, -2.08 cm-1/GPa for FTO(2/4)E2 on 4H-SiC (11-20) face and -2.70 cm-1/GPa for FTO(2/6)E2 on 6H-SiC (0001) face. Determination of these coefficients has made it possible to evaluate the residual stress in SiC crystal quantitatively by micro-Raman spectroscopy. We evaluated the residual stress in SiC substrate that was grown in our laboratory by utilizing the results obtained in this study. The result of estimation indicated that the SiC substrate with a diameter of 6 inch remained residual stress as low as ±15 MPa.
Laying hens have a unique bone turnover due to the daily egg laying cycle. Laying hens have three distinctive kinds of bones related to egg formation: cortical, cancellous, and medullary bones. Cortical bone is a compact structural bone, whereas cancellous bone is the three-dimensional lattice-like honeycomb architecture at the end of long bones. Medullary bone is a highly labile woven bone lying in the marrow cavities. Medullary bone acts as Ca storage for egg shell formation. Thus, bone quality is closely related with egg production and eggshell quality. During the daily egg laying cycle, medullary bone osteoclasts alternately cease and accelerate bone resorption. Although osteoclast numbers are not changed during the daily egg laying cycle, considerable morphological changes in osteoclasts occur along with changes in calcium requirements for egg shell formation. Furthermore, the selection of proper methods is critical to obtain precise bone evaluation data, and include bone ashing, densitometric techniques, mechanical testing, or histomorphometry to evaluate bone status in laying hens. Since bone metabolism in laying hens is related to economic and animal welfare issues, better understanding of bone metabolism in laying hens would be important to enhance productivity and improve animal welfare.
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.
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 focused on detailed evaluations of properties of the ultra-thin pore-seal layer (< 3 nm-thick), such as Cu diffusion barrier property and thermal stability. Cu diffusion into dense thermal silica and porous silica low-k which are covered with the pore seal layer was evaluated using metal-insulator-semiconductor (MIS) capacitors under bias thermal stress (BTS). Triangular voltage sweep (TVS) measurement shows that the ultra-thin layer on dense thermal silica suppresses the drift of Cu ions. The Time-Dependent Dielectric Breakdown (TDDB) lifetime of porous silica low-k covered with the ultra-thin pore seal layer results in a drastic increase of the capacitor lifetime with respect to the no-pore-seal control system (stable at 125 °C at least for 10000 s). Thermal decomposition of bulk material of the pore sealant was measured by thermal gravity (TG) test in nitrogen. Bulk material did not decompose through around 350 °C. The amount of ultra-thin pore seal layer fabricated on silicon wafer after thermal cycle stress in vacuum was measured by x-ray photoelectron spectroscopy (XPS). Amount of pore sealant did not decrease even after 2 cycles of 20 min, at 250 °C. Those results show that the ultra-thin layer, which we propose here, has a potential as a pore seal layer for porous low-k films.
Newly developed interferon-gamma release assays have become commercially available to detect tuberculosis (TB) infection in adults. However, little is known about their performance in children. We compared test results between the QuantiFERON-TB® Gold test (QFT) and tuberculin skin test (TST) in young children living with pulmonary TB patients in Cambodia. Of 195 children tested with both QFT and TST, the TST-positive rate of 24% was significantly higher than the QFT-positive rate of 17%. The agreement between the test results was considerable (κ-coefficient 0·63). Positive rates increased from 6% to 32% for QFT and from 15% to 43% for TST, according to the sputum smear grades of the index cases. The presence of Bacille Calmette-Guérin (BCG) scars did not significantly affect the results of TST or QFT in a logistic regression analysis. In conclusion, QFT can be a substitute for TST in detecting latent TB infection in childhood contacts aged ⩽5 years, especially in those who may have a false-positive TST due to BCG vaccination or non-tuberculous mycobacterial infection.
It seems that no satisfactory TE property has been found in n-type oxide bulk materials even though Al-doped ZnO and La-doped SrTiO3 have high thermoelectric (TE) responses. Difficulty in developing high-performance TE materials seems to lie in finding low thermal conductivity in such oxides. The purpose of this study is to find a possibility to make an n-type TE oxide bulk material having low thermal conductivity and excellent TE properties as well. For this purpose, we fabricated and examined a series of composites constructed of TiO2 and Ln-doped SrTiO3 fine crystals. The composites were prepared via two processing steps: (1) precursor oxide preparation by wet processes; (2) sintering by using spark plasma sintering (SPS) apparatus. The microscopic structure was examined by using scanning electron microscope (SEM; HITACHI S-4500 model) attached with an energy dispersive x-ray spectroscopy. The electrical conductivities and the Seebeck coefficients were measured simultaneously using an ULVAC ZEM-1 instrument in helium atmosphere. The thermal diffusivities were measured by a laser flash method in vacuum. The composites obtained here were found to commonly have a mosaic type texture constructed of TiO2 and SrTiO3 fine particles with a typical size of 500 nm. The thermal conductivity values measured for three samples with different contents are ranged between 3 and 4 Wm-1K-1 in the temperature range from room temperature to 800 C. The values are apparently lower than the value for single crystal SrTiO3 samples presented in literature. Taking account the other TE data, e.g. Seebeck coefficient and electrical conductivity, we calculated dimensionless figure of merit, ZT, to be at maximum 0.15 at 800°C.
A parallel resistance model (PRM), in which the total resistance, Rtotal, is given by a parallel connection of resistance of a filament, Rfila, and that of a film excluding a filament, Rexcl, was proposed to understand DC electric properties of resistive RAM (ReRAM). Here, the relationship of 1/Rtotal = 1/Rfila + 1/Rexcl is satisfied. To prove the validity of this model, the dependence of the relationship between resistance and temperature, R(T), of Pt/NiO/Pt on an area of a top electrode, S, was investigated. It was clarified that R(T) depended on S, which is the result definitely expected by the PRM. It was also clarified that smaller S is crucial to observe intrinsic properties of a filament of ReRAM.
A new simulation model is developed, in which the interaction between the macroscopic and microscopic plasma processes is able to be taken into account self-consistently. Magnetohydrodynamic (MHD) simulation and particle-in-cell (PIC) simulation are directly connected and performed simultaneously. This MHD–PIC connection model is first applied to the study of the quiet auroral arc formation process. It is an example of our challenge to create the holistic simulation framework, that is, the heterogeneous schemes that can be unified by the state-of-the-art numerical technique. In this paper, we will explain the algorithm of our new model and show the results which have been calculated on the Earth Simulator.
Using deep level transient spectroscopy (DLTS) measurements with
zero-bias and reverse-bias cooling, we have observed new metastable
defects (EM1, EM2 and EM3) in n-type silicon by hydrogen implantation
at temperature as low as 88 K. We have investigated the trap
parameters of these metastable defects and their concentration
depth profiles. Hydrogen ion implantation was performed with
energies of 80 keV, 90 keV, and 100 keV to a dose of
2 × 1010 cm−2.
The silicon substrate temperature was kept at as low
as 88 K during hydrogen implantation and then was raised naturally
to room temperature. From analysis of Arrhenius plots, the energy
levels of EM1, EM2 and EM3 are obtained to be Ec-0.29 eV, Ec-0.41 eV
and Ec-0.55 eV, respectively. The depth profiles of metastable
defects in 90-keV samples have a peak in the concentration around
the depth of 0.68 µm, which is shallow compared with the projected
range of 90 keV hydrogen. The peak position becomes deeper as the
energy of ion implantation increases. This indicates that the
production of metastable defects is caused by ion implantation.
Additionally, comparison with helium-implanted samples suggests
that implanted hydrogen is included in these metastable defects.