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Recent years have seen an exponential increase in the variety of healthcare data captured across numerous sources. However, mechanisms to leverage these data sources to support scientific investigation have remained limited. In 2013 the Pediatric Heart Network (PHN), funded by the National Heart, Lung, and Blood Institute, developed the Integrated CARdiac Data and Outcomes (iCARD) Collaborative with the goals of leveraging available data sources to aid in efficiently planning and conducting PHN studies; supporting integration of PHN data with other sources to foster novel research otherwise not possible; and mentoring young investigators in these areas. This review describes lessons learned through the development of iCARD, initial efforts and scientific output, challenges, and future directions. This information can aid in the use and optimisation of data integration methodologies across other research networks and organisations.
This study tested whether the association between interparental conflict and adolescent externalizing symptoms was moderated by a polygenic composite indexing low dopamine activity (i.e., 7-repeat allele of DRD4; Val alleles of COMT; 10-repeat variants of DAT1) in a sample of seventh-grade adolescents (Mean age = 13.0 years) and their parents. Using a longitudinal, autoregressive design, observational assessments of interparental conflict at Wave 1 predicted increases in a multi-informant measurement of youth externalizing symptoms 2 years later at Wave 3 only for children who were high on the hypodopaminergic composite. Moderation was expressed in a “for better” or “for worse” form hypothesized by differential susceptibility theory. Thus, children high on the dopaminergic composite experienced more externalizing problems than their peers when faced with more destructive conflicts but also fewer externalizing problems when exposed to more constructive interparental conflicts. Mediated moderation findings indicated that adolescent reports of their emotional insecurity in the interparental relationship partially explained the greater genetic susceptibility experienced by these children. More specifically, the dopamine composite moderated the association between Wave 1 interparental conflict and emotional insecurity 1 year later at Wave 2 in the same “for better” or “for worse” pattern as externalizing symptoms. Adolescent insecurity at Wave 2, in turn, predicted their greater externalizing symptoms 1 year later at Wave 3. Post hoc analyses further revealed that the 7-repeat allele of the dopamine receptor D4 (DRD4) gene was the primary source of plasticity in the polygenic composite. Results are discussed as to how they advance process-oriented Gene x Environment models of emotion regulation.
With the recent discovery of a dozen dusty star-forming galaxies and around 30 quasars at z > 5 that are hyper-luminous in the infrared (μ LIR > 1013 L⊙, where μ is a lensing magnification factor), the possibility has opened up for SPICA, the proposed ESA M5 mid-/far-infrared mission, to extend its spectroscopic studies toward the epoch of reionisation and beyond. In this paper, we examine the feasibility and scientific potential of such observations with SPICA’s far-infrared spectrometer SAFARI, which will probe a spectral range (35–230 μm) that will be unexplored by ALMA and JWST. Our simulations show that SAFARI is capable of delivering good-quality spectra for hyper-luminous infrared galaxies at z = 5 − 10, allowing us to sample spectral features in the rest-frame mid-infrared and to investigate a host of key scientific issues, such as the relative importance of star formation versus AGN, the hardness of the radiation field, the level of chemical enrichment, and the properties of the molecular gas. From a broader perspective, SAFARI offers the potential to open up a new frontier in the study of the early Universe, providing access to uniquely powerful spectral features for probing first-generation objects, such as the key cooling lines of low-metallicity or metal-free forming galaxies (fine-structure and H2 lines) and emission features of solid compounds freshly synthesised by Population III supernovae. Ultimately, SAFARI’s ability to explore the high-redshift Universe will be determined by the availability of sufficiently bright targets (whether intrinsically luminous or gravitationally lensed). With its launch expected around 2030, SPICA is ideally positioned to take full advantage of upcoming wide-field surveys such as LSST, SKA, Euclid, and WFIRST, which are likely to provide extraordinary targets for SAFARI.
We performed a new series of measurements on samples that were part of early measurements on radiocarbon (14C) dating made in 1948–1949. Our results show generally good agreement to the data published in 1949–1951, despite vast changes in technology, with only two exceptions where there was a discrepancy in the original studies. Our new measurements give calibrated ages that overlap with the known ages. We dated several samples at four different laboratories, and so we were also able to make a small intercomparison at the same time. In addition, new measurements on samples from other Egyptian materials used by Libby and co-workers were made at UC Irvine. Samples of tree rings used in the original studies (from Broken Flute Cave and Centennial Stump) were obtained from the University of Arizona Laboratory of Tree-Ring Research archive and remeasured. New data were compared to the original studies and other records.
We present a model for the force acting to fragment a biofilm-seeded microbial aggregate in shear flow, which we derive by coupling an existing model for the shape and orientation of a deforming ellipsoid with one for the surface force density on a solid ellipsoid. The model can be used to simulate the motion, shape, surface force density, and breakage of colloidal aggregates in shear flow. We apply the model to the case of exhaustive fragmentation of microbial aggregates in order to compute a post-fragmentation density function, indicating the likelihood of a fragmenting aggregate yielding daughter aggregates of a certain size.
Our current knowledge of star formation and accretion luminosity at high redshift (z > 3–4), as well as the possible connections between them, relies mostly on observations in the rest-frame ultraviolet, which are strongly affected by dust obscuration. Due to the lack of sensitivity of past and current infrared instrumentation, so far it has not been possible to get a glimpse into the early phases of the dust-obscured Universe. Among the next generation of infrared observatories, SPICA, observing in the 12–350 µm range, will be the only facility that can enable us to trace the evolution of the obscured star-formation rate and black-hole accretion rate densities over cosmic time, from the peak of their activity back to the reionisation epoch (i.e., 3 < z ≲ 6–7), where its predecessors had severe limitations. Here, we discuss the potential of photometric surveys performed with the SPICA mid-infrared instrument, enabled by the very low level of impact of dust obscuration in a band centred at 34 µm. These unique unbiased photometric surveys that SPICA will perform will fully characterise the evolution of AGNs and star-forming galaxies after reionisation.
The Square Kilometre Array will be an amazing instrument for pulsar astronomy. While the full SKA will be sensitive enough to detect all pulsars in the Galaxy visible from Earth, already with SKA1, pulsar searches will discover enough pulsars to increase the currently known population by a factor of four, no doubt including a range of amazing unknown sources. Real time processing is needed to deal with the 60 PB of pulsar search data collected per day, using a signal processing pipeline required to perform more than 10 POps. Here we present the suggested design of the pulsar search engine for the SKA and discuss challenges and solutions to the pulsar search venture.
The μ–z diagram (Figure 1) plots the observed internal proper motion μ versus redshift z for 32 extragalactic radio sources associated with active galactic nuclei. The observed points fall below an upper bound which decreases with redshift; there is a statistically significant anticorrelation between redshift and internal proper motion.
We have conducted a systematic study of the milliarcsecond structure of a complete, flux-density limited sample of strong radio sources selected at 5 GHz. We have made 5 GHz maps at two epochs of the 45 compact sources in the sample, and third-epoch observations are in progress. Our intention was to explore the full range of morphologies exhibited by compact radio sources, to search for new superluminal sources, and to determine how widespread such phenomena as parsec-scale jets, alignment of parsec-scale and kiloparsec-scale jets, and superluminal motion are. In addition, we hoped to use this well-defined sample for statistical tests of the beaming theories.
Since 1977 we have been engaged on a project to survey the milliarcsecond structure and internal motions of a complete, unbiased sample of 65 radio sources (Pearson and Readhead 1984). One of the goals of the project was to discover more superluminal sources and find out how common they are. The sample contains three established superluminal sources (3C 179, 3C 345, and BL Lacertae); so far we have discovered three new superluminal quasars (0850+581, 1642+690, and 1928+738), and a fourth (3C 216) that may be superluminal. Thus at least six out of the 65 sources are superluminal, and we expect to find more as our observations proceed.
The NOSAMS facility at Woods Hole Oceanographic Institution has started to develop and apply techniques for measuring very small samples on a standard Tandetron accelerator mass spectrometry (AMS) system with high-current hemispherical Cs sputter ion sources. Over the past year, results on samples ranging from 7 to 160 μg C showed both the feasibility of such analyses and the present limitations on reducing the size of solid carbon samples. One of the main factors affecting the AMS results is the dependence of a number of the beam optics parameters on the extracted ion beam current. The extracted currents range from 0.5 to 10 μA of 12C− for the sample sizes given above. We here discuss the setup of the AMS system and methods for reliable small-sample measurements and give the AMS-related limits to sample size and the measurement uncertainties.
Techniques for making precise and accurate radiocarbon accelerator mass spectrometry (AMS) measurements on samples containing less than a few hundred micrograms of carbon are being developed at the NOSAMS facility. A detailed examination of all aspects of the sample preparation and data analysis process shows encouraging results. Small quantities of CO2 are reduced to graphite over cobalt catalyst at an optimal temperature of 605°. Measured 14C/12C ratios of the resulting targets are affected by machine-induced isotopic fractionation, which appears directly related to the decrease in ion current generated by the smaller sample sizes. It is possible to compensate effectively for this fractionation by measuring samples relative to small standards of identical size. Examination of the various potential sources of background 14C contamination indicates that the sample combustion process is the largest contributor, adding ca. 1 μg of carbon with a less-than-modern 14C concentration.
The Cosmic Background Imager (CBI) is an instrument designed to make images of the cosmic microwave background radiation and to measure its statistical properties on angular scales from about 3 arc minutes to one degree (spherical harmonic scales from l ˜ 4250 down to l ˜ 400). The CBI is a 13-element interferometer mounted on a 6 meter platform operating in ten 1-GHz frequency bands from 26 GHz to 36 GHz. The instantaneous field of view of the instrument is 45 arcmin (FWHM) and its resolution ranges from 3 to 10 arcmin; larger fields can be imaged by mosaicing. At this frequency and resolution, the primary foreground is due to discrete extragalactic sources, which are monitored at the Owens Valley Radio Observatory and subtracted from the CBI visibility measurements.
The instrument has been making observations since late 1999 of both primordial CMB fluctuations and the Sunyaev-Zeldovich effect in clusters of galaxies from its site at an altitude of 5080 meters near San Pedro de Atacama, in northern Chile. Observations will continue until August 2001 or later. We present preliminary results from the first few months of observations.
We report the direct detection of cyclic diameter variations in the Mira variable χ Cygni. Interferometric observations made between 1997 July and 1998 September, using the Cambridge Optical Aperture Synthesis Telescope (COAST) indicate periodic changes in the apparent angular diameter with amplitude 45 per-cent of the smallest value.
The measurements were made in a 50 nm bandpass centred on 905 nm, which is only moderately contaminated by molecular absorption features. To assess the effects of atmospheric stratification on the apparent diameter measured in this band, we have also measured near-infrared diameters for a sample of five Miras, in both the J-band (1.3 μm) and Wing's (1971) 1.04 μm band, which is expected to isolate essentially pure continuum emission. We present J-band visibility curves which indicate that the intensity profiles of the stars in the sample differ greatly from each other.
A series of VLBI surveys of complete samples of radio sources selected at 5 GHz (Pearson & Readhead 1988, hereafter PR; Xu et al. 1995 and references therein) has revealed that ≃ 10% of the objects are “Compact Symmetric Objects” (CSOs), in which high-luminosity radio emission regions are seen on both sides of the center of activity on scales less than one kiloparsec (Phillips & Mutel 1982; Readhead et al. 1984; Conway et al. 1992; Wilkinson et al. 1994). In order to be sure that an object is a CSO, either the center of activity must be pinpointed (Taylor et al. 1996) or compelling morphological evidence of symmetric structure must be found.
Generalized anxiety disorder (GAD) and panic disorder (PD) differ in their biology and co-morbidities. We hypothesized that GAD but not PD symptoms at the age of 15 years are associated with depression diagnosis at 18 years.
Using longitudinal data from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort we examined relationships of GAD and PD symptoms (measured by the Development and Well-Being Assessment) at 15 years with depression at 18 years (by the Clinical Interview Schedule – Revised) using logistic regression. We excluded adolescents already depressed at 15 years and adjusted for social class, maternal education, birth order, gender, alcohol intake and smoking. We repeated these analyses following multiple imputation for missing data.
In the sample with complete data (n = 2835), high and moderate GAD symptoms in adolescents not depressed at 15 years were associated with increased risk of depression at 18 years both in unadjusted analyses and adjusting for PD symptoms at 15 years and the above potential confounders. The adjusted odds ratio (OR) for depression at 18 years in adolescents with high relative to low GAD scores was 5.2 [95% confidence interval (CI) 3.0–9.1, overall p < 0.0001]. There were no associations between PD symptoms and depression at 18 years in any model (high relative to low PD scores, adjusted OR = 1.3, 95% CI 0.3–4.8, overall p = 0.737). Missing data imputation strengthened the relationship of GAD symptoms with depression (high relative to low GAD scores, OR = 6.2, 95% CI 3.9–9.9) but those for PD became weaker.
Symptoms of GAD but not PD at 15 years are associated with depression at 18 years. Clinicians should be aware that adolescents with GAD symptoms may develop depression.
Figure 1 shows hybrid maps of the core of 3C 273B at five epochs, made with arrays of 4 or 5 VLBI antennas. The maps span a period of 3.5 years. They all show a bright eastern peak and a lower-brightness extension to the west. There is a local maximum in the western extension between 6 and 8 milliarcsec from the main peak. This “blob” moves steadily further away from the main peak along a roughly straight line in PA −116° ± 2°. Compare this with the position angle of the 25-arcsec optical jet, −137°. The maps show a slight curvature to the south with increasing separation from the main peak. Lower-resolution VLBI maps at lower frequencies show that this curvature continues at greater separations, suggesting a smooth connection between the milli-arcsecond position angle and the position angle of the optical jet. In our latest map (1981.09) the blob is no longer detectable with the limited dynamic range of the VLBI network (about 20:1).
The Herschel Space Observatory was the fourth cornerstone mission in the European Space Agency (ESA) science programme with excellent broad band imaging capabilities in the sub-mm and far-infrared part of the spectrum. Although the spacecraft finished its observations in 2013, it left a large legacy dataset that is far from having been fully scrutinised and still has a large potential for new scientific discoveries. This is specifically true for the photometric observations of the PACS and SPIRE instruments. Some source catalogues have already been produced by individual observing programs, but there are many observations that risk to remain unexplored. To maximise the science return of the SPIRE and PACS data sets, we are in the process of building the Herschel Point Source Catalogue (HPSC) from all primary and parallel mode observations. Our homogeneous source extraction enables a systematic and unbiased comparison of sensitivity across the different Herschel fields that single programs will generally not be able to provide. The catalogue will be made available online through archives like the Herschel Science Archive (HSA), the Infrared Science Archive (IRSA), and the Strasbourg Astronomical Data Center (CDS).