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The COllaborative project of Development of Anthropometrical measures in Twins (CODATwins) project is a large international collaborative effort to analyze individual-level phenotype data from twins in multiple cohorts from different environments. The main objective is to study factors that modify genetic and environmental variation of height, body mass index (BMI, kg/m2) and size at birth, and additionally to address other research questions such as long-term consequences of birth size. The project started in 2013 and is open to all twin projects in the world having height and weight measures on twins with information on zygosity. Thus far, 54 twin projects from 24 countries have provided individual-level data. The CODATwins database includes 489,981 twin individuals (228,635 complete twin pairs). Since many twin cohorts have collected longitudinal data, there is a total of 1,049,785 height and weight observations. For many cohorts, we also have information on birth weight and length, own smoking behavior and own or parental education. We found that the heritability estimates of height and BMI systematically changed from infancy to old age. Remarkably, only minor differences in the heritability estimates were found across cultural–geographic regions, measurement time and birth cohort for height and BMI. In addition to genetic epidemiological studies, we looked at associations of height and BMI with education, birth weight and smoking status. Within-family analyses examined differences within same-sex and opposite-sex dizygotic twins in birth size and later development. The CODATwins project demonstrates the feasibility and value of international collaboration to address gene-by-exposure interactions that require large sample sizes and address the effects of different exposures across time, geographical regions and socioeconomic status.
A new generation of high power laser facilities will provide laser pulses with extremely high powers of 10 petawatt (PW) and even 100 PW, capable of reaching intensities of
in the laser focus. These ultra-high intensities are nevertheless lower than the Schwinger intensity
at which the theory of quantum electrodynamics (QED) predicts that a large part of the energy of the laser photons will be transformed to hard Gamma-ray photons and even to matter, via electron–positron pair production. To enable the investigation of this physics at the intensities achievable with the next generation of high power laser facilities, an approach involving the interaction of two colliding PW laser pulses is being adopted. Theoretical simulations predict strong QED effects with colliding laser pulses of
focused to intensities
We theoretically investigate the impact of feedback and its metallicity dependence in massive star formation from prestellar cores at all metallicity range. We include the feedback by MHD disk winds, radiation pressure, and photoevaporation solving the evolution of protostars and accretion flows self-consistently. Interestingly, we find that the feedback does not set the upper mass limit of stellar birth mass at any metallicity. At the solar metallicity, the MHD disk wind is the dominant feedback to set the star formation efficiencies (SFEs) from the prestellar cores similar to low-mass star formation. The SFE is found to be lower at lower surface density environment. The photoevaporation becomes significant at the low metallicity of Z < 10−2 Z⊙. Considering this efficient photoevaporation, we conclude that the IMF slope is steeper, i.e., massive stars are rarer at the extremely metal-poor environment of 10−5 − 10−3Z⊙. Our study raises a question on the common assumption of the universal IMF with a truncated at 100M⊙. Since the total feedback strength in the cluster/galaxy scale is sensitive to the number fraction of massive stars, the re-evaluations of IMF at various environments are necessary.
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.
Major depressive disorder (MDD) is moderately heritable, however genome-wide association studies (GWAS) for MDD, as well as for related continuous outcomes, have not shown consistent results. Attempts to elucidate the genetic basis of MDD may be hindered by heterogeneity in diagnosis. The Center for Epidemiological Studies Depression (CES-D) scale provides a widely used tool for measuring depressive symptoms clustered in four different domains which can be combined together into a total score but also can be analysed as separate symptom domains.
We performed a meta-analysis of GWAS of the CES-D symptom clusters. We recruited 12 cohorts with the 20- or 10-item CES-D scale (32 528 persons).
One single nucleotide polymorphism (SNP), rs713224, located near the brain-expressed melatonin receptor (MTNR1A) gene, was associated with the somatic complaints domain of depression symptoms, with borderline genome-wide significance (pdiscovery = 3.82 × 10−8). The SNP was analysed in an additional five cohorts comprising the replication sample (6813 persons). However, the association was not consistent among the replication sample (pdiscovery+replication = 1.10 × 10−6) with evidence of heterogeneity.
Despite the effort to harmonize the phenotypes across cohorts and participants, our study is still underpowered to detect consistent association for depression, even by means of symptom classification. On the contrary, the SNP-based heritability and co-heritability estimation results suggest that a very minor part of the variation could be captured by GWAS, explaining the reason of sparse findings.
Oxidation tests of Cr containing Co-based superalloys with compositions of Co-20at.%Ni-9at.%Al-9at.%W-x at.%Cr (x = 2, 4, 6, 8 and 10) have been carried out at 1173 and 1273 K in air. Oxidation resistance is improved upon alloying with Cr not only at 1173 K but also at 1273 K. The weight gain of the 10at.%Cr alloy oxidized at 1173 K is similar to that of the 5th generation Ni-based superalloy of TMS-173. Alloying with Cr is efficient to improve oxidation resistance, however, the shape of γ’ precipitates is rounded and the alignment of the precipitates along the <100> direction becomes less pronounced upon alloying with Cr.
The crystal structure of the δ1p phase in the Fe-Zn system has been refined by single-crystal synchrotron X-ray diffraction combined with ultra-high resolution scanning transmission electron microscopy. The crystal structure can be described to build up with Fe-centered Zn12 icosahedra. The deformation properties obtained by single-crystal micropillar compression tests of the δ1p phase is discussed in terms of the arrangement of the Fe-centered Zn12 icosahedra in contrast with the ζ phase in the Fe-Zn system.
Twenty-five years ago the desktop computer started becoming ubiquitous in the scientific lab. Researchers were delighted with its ability to both control instrumentation and acquire data on a single system, but they were not completely satisfied. There were often gaps in knowledge that they thought might be gained if they just had more data and they could get the data faster. Computer technology has evolved in keeping with Moore’s Law meeting those desires; however those improvements have of late become both a boon and bane for researchers. Computers are now capable of producing high speed data streams containing terabytes of information; capabilities that evolved faster than envisioned last century. Software to handle large scientific data sets has not kept up. How much information might be lost through accidental mismanagement or how many discoveries are missed through data overload are now vital questions. An important new task in most scientific disciplines involves developing methods to address those issues and to create the software that can handle large data sets with an eye towards scalability. This software must create archived, indexed, and searchable data from heterogeneous instrumentation for the implementation of a strong data-driven materials development strategy. At the National Center for Photovoltaics in the National Renewable Energy Laboratory, we began development a few years ago on a Laboratory Information Management System (LIMS) designed to handle lab-wide scientific data acquisition, management, processing and mining needs for physics and materials science data, and with a specific focus towards future scalability for new equipment or research focuses. We will present the decisions, processes, and problems we went through while building our LIMS system for materials research, its current operational state and our steps for future development.
The High Throughput Experimentation (HTE) project of the Joint Center for Artificial Photosynthesis (JCAP, http://solarfuelshub.org/) performs accelerated discovery of new earth-abundant photoabsorbers and electrocatalysts. Through collaboration within the DOE solar fuels hub and with the broader research community, the new materials will be utilized in devices that efficiently convert solar energy, water and carbon dioxide into transportation fuels. JCAP-HTE builds high-throughput pipelines for the synthesis, screening and characterization of photoelectrochemical materials. In addition to a summary of these pipelines, we will describe several new screening instruments for high throughput (photo-)electrochemical measurements. These instruments are not only optimized for screening against solar fuels requirements, but also provide new tools for the broader combinatorial materials science community. We will also describe the high throughput discovery, follow-on verification, and device implementation of a new quaternary metal oxide catalyst. This rapid technology development from discovery to device implementation is a hallmark of the multi-faceted JCAP research effort.
Femtosecond near IR laser irradiation is explored as a general methodology to produce metal nanoparticles from metal precursor solutions. Initial studies of the formation and transformations of gold nanoparticles in aqueous solution are used as model processes to evaluate the effects of laser parameters, reaction medium and surfactants in controlling metal nanoparticle formation. The addition of polymer surfactants such as poly(ethylene glycol) (PEG) was found to significantly accelerate Au(III) reduction as compared to surfactant-free systems. Photo-reduction for aqueous solutions of Au(III) in the presence of PEG results in relatively small narrowly dispersed spherical gold nanoparticles compared to relatively large well-formed crystalline nanoparticles that are observed in the absence of surfactants. Varying the concentration of PEG is an effective approach to tune the diameter and size distribution from 3.9±0.7 nm to 11±2.4 nm for Au nanoparticles produced by laser processing.
We studied the diffusive transport of Cs, Np, Am and Co in compacted sandbentonite mixtures by using the through-diffusion method. The experiments for Cs were performed under various aqueous compositions. Effective diffusivity (De) values of 4.7×10–10 to 5.9×10–9 m2 s–1 were obtained with a somewhat large variation. Apparent diffusivity (Da) values, on the other hand, showed less variation, ranging from 2.0×10–12 to 6.2×10–12 m2 s–1. The results indicated that diffusive flux was proportional to the concentration gradient on the basis of the amount of Cs in the unit volume of the compacted sand-bentonite mixtures rather than the Cs concentration gradient in pore water. Because the former concentration gradient in the mixtures was nearly equal to that of adsorbed Cs, the diffusion of Cs in the mixtures was probably dominated by the concentration gradient of the Cs adsorbed on the mixtures. In addition, the effective/apparent diffusivity of 237Np(IV) and apparent diffusivity of 241Am(III) and 60Co(II) in the mixtures were determined in 0.3/0.03 mol l–1 (NH4)2CO3/Na2S2O4 solution.
Origins of superluminous supernovae (SLSNe) discovered by recent SN surveys are still not known well. One idea to explain the huge luminosity is the collision of dense CSM and SN ejecta. If SN ejecta is surrounded by dense CSM, the kinetic energy of SN ejecta is efficiently converted to radiation energy, making them very bright. To see how well this idea works quantitatively, we performed numerical simulations of collisions of SN ejecta and dense CSM by using one-dimensional radiation hydrodynamics code STELLA and obtained light curves (LCs) resulting from the collision. First, we show the results of our LC modeling of SLSN 2006gy. We find that physical parameters of dense CSM estimated by using the idea of shock breakout in dense CSM (e.g., Chevalier & Irwin 2011, Moriya & Tominaga 2012) can explain the LC properties of SN 2006gy well. The dense CSM's radius is about 1016 cm and its mass about 15 M⊙. It should be ejected within a few decades before the explosion of the progenitor. We also discuss how LCs change with different CSM and SN ejecta properties and origins of the diversity of H-rich SLSNe. This can potentially be a probe to see diversities in mass-loss properties of the progenitors. Finally, we also discuss a possible signature of SN ejecta-CSM interaction which can be found in H-poor SLSN.
We report the growth of single crystals by a flux method in ambient pressure and tri-axial orientation under modulated rotation magnetic fields (MRFs) on REBa2Cu4O8 (RE124, RE; rare earth elements) compounds. RE124 crystals were grown for RE = Y, Sm, Eu, Gd, Dy, Ho, Er, Tm, and Yb through appropriate choice of source compounds. All the obtained RE124 powders were tri-axially aligned in MRF of 10T, whereas magnetization axes depended on the type of RE. Moreover, it was found from the changes in the degrees of c-axis and inplane orientation that tri-axial magnetic anisotropies of RE124 also depended on the type of RE. This indicates that it appropriate choice of RE is important for the fabrication of tri-axial oriented ceramics in lower magnetic field conditions.
The near-infrared (NIR) spectral range (2–5 μm) contains a number of interesting features for the study of the interstellar medium. In particular, the aromatic and aliphatic components in carbonaceous dust can be investigated most efficiently with the NIR spectroscopy. We analyze NIR spectra of the diffuse Galactic emission taken with the Infrared Camera onboard AKARI and find that the aliphatic to aromatic emission band ratio decreases toward the ionized gas, which suggests processing of the band carriers in the ionized region.
Creep tests of monocrystalline Co–Al–W-based alloys with a tensile stress of 137 MPa at 1000 °C were carried out. The microstructures of the crept specimens were investigated by scanning electron microscope (SEM) and transmission electron microscope (TEM). The γ′ phase in the specimens was not only elongated along the stress direction as expected by the sign of the lattice misfit but also elongated in one of the <100> directions perpendicular to the stress direction. As a result, the shape of the γ′ phase is not a rod but a plate. In the TEM images, it was observed that many SISFs are induced in the γ′ phase by creep. A similar microstructure is also observed in Ni-based superalloys, but the microstructure was formed under relatively lower temperatures and higher applied stresses. The observation of numerous stacking faults in the γ′ phase is a clear indication that the γ′ phase precipitated in the present alloy is weaker than that in many modern Ni-based superalloys.
Near-infrared (NIR; 2.5–5 μm) low-resolution
(λ/Δλ ~ 100) spectra were obtained for a
number of Galactic and extragalactic objects with the Infrared Camera (IRC) in the AKARI
warm mission. These data provide us with the first opportunity to make a systematic study
of the 3.3–3.5 μm PAH features in a galactic scale as well as within an
object. Whereas the 3.3 μm band is well resolved in most spectra, the
3.5 μm band is not clearly separated from the 3.4 μm
band in the IRC spectrum. The intensity ratio of the summation of the 3.4 and
3.5 μm bands to the 3.3 μm band shows a tendency to
increase towards the Galactic center, although a large variation in the ratio is also seen
in a local scale. A search for deuterated PAH features in the 4 μm region
is carried out in IRC NIR spectra. Emission lines originating from the ionized gas
together with the detector anomaly hamper an accurate search at certain wavelengths, but
little convincing evidence has so far been obtained for the presence of significant
features in 4.2–4.7 μm. A conservative upper limit of a few percents is
obtained for the integrated intensity ratio of the 4.4–4.7 μm possible
features to the 3.3–3.5 μm PAH features in the spectra so far