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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.
Filamentary structures can form within the beam of protons accelerated during the interaction of an intense laser pulse with an ultrathin foil target. Such behaviour is shown to be dependent upon the formation time of quasi-static magnetic field structures throughout the target volume and the extent of the rear surface proton expansion over the same period. This is observed via both numerical and experimental investigations. By controlling the intensity profile of the laser drive, via the use of two temporally separated pulses, both the initial rear surface proton expansion and magnetic field formation time can be varied, resulting in modification to the degree of filamentary structure present within the laser-driven proton beam.
Phased VLA observations of the Galactic center magnetar J1745-2900 over 8-12 GHz reveal rich single pulse behavior. The average profile is comprised of several distinct components and is fairly stable over day timescales and GHz frequencies. The average profile is dominated by the jitter of relatively narrow pulses. The pulses in each of the four profile components are uncorrelated in phase and amplitude, although the occurrence of pulse components 1 and 2 appear to be correlated. Using a collection of the brightest individual pulses, we verify that the index of the dispersion law is consistent with the expected cold plasma value of 2. The scattering time is weakly constrained, but consistent with previous measurements, while the dispersion measure DM = 1763+3−10 pc cm−3 is lower than previous measurements, which could be a result of time variability in the line-of-sight column density or changing pulse profile shape over time or frequency.
Various medications and devices are available for facilitation of emergent endotracheal intubations (EETIs). The objective of this study was to survey which medications and devices are being utilized for intubation by Canadian physicians.
A clinical scenario-based survey was developed to determine which medications physicians would administer to facilitate EETI, their first choice of intubation device, and backup strategy should their first choice fail. The survey was distributed to Canadian emergency medicine (EM) and intensive care unit (ICU) physicians using web-based and postal methods. Physicians were asked questions based on three scenarios (trauma; pneumonia; heart failure) and responded using a 5-point scale ranging from “always” to “never” to capture usual practice.
The survey response rate was 50.2% (882/1,758). Most physicians indicated a Macintosh blade with direct laryngoscopy would “always/often” be their first choice of intubation device in the three scenarios (mean 85% [79%-89%]) followed by video laryngoscopy (mean 37% [30%-49%]). The most common backup device chosen was an extraglottic device (mean 59% [56%-60%]). The medications most physicians would “always/often” administer were fentanyl (mean 45% [42%-51%]) and etomidate (mean 38% [25%-50%]). EM physicians were more likely than ICU physicians to paralyze patients for EETI (adjusted odds ratio 3.40; 95% CI 2.90-4.00).
Most EM and ICU physicians utilize direct laryngoscopy with a Macintosh blade as a primary device for EETI and an extraglottic device as a backup strategy. This survey highlights variation in Canadian practice patterns for some aspects of intubation in critically ill patients.
The next generation millimeter to submillimeter wavelength synthesis telescope, the Atacama Large Millimeter Array (ALMA), is an excellent instrument for direct and indirect detection of extrasolar giant planets and imaging of extrasolar planetary systems at all evolutionary stages. We examine some possibilities of ALMA in this respect here.
Physical health and, in particular, frailty may be associated with psychological factors among older adults. We aimed to investigate the relationships between aspects of psychological distress and progression of frailty over time among older adults.
We used a longitudinal observational study design with 624 participants aged over 60 years (mean age=72.75, s.d.=7.21, 68% female) completing a baseline comprehensive biopsychosocial geriatric assessment, and 447 returning for a follow-up assessment 2 years later. Aspects of psychological distress, physical health, and frailty were analysed for the purposes of this study. We employed a series of logistic regression analyses to determine psychological predictors of changing states of aspects of frailty over time.
With individual components of frailty, neuroticism and age predicted negative transitions of exhaustion and grip strength, respectively, whereas age alone was a predictor of transitions in overall frailty scores based on four components.
We conclude that neuroticism and age may impact upon physical frailty and its progression over time in an ageing population. These findings may reflect the tendency for those with high levels of neuroticism to endorse negative symptoms, or alternatively, neuroticism may result in exhaustion via worry in an older population. Further research is required to further elucidate this relationship.
High-intensity laser–solid interactions generate relativistic electrons, as well as high-energy (multi-MeV) ions and x-rays. The directionality, spectra and total number of electrons that escape a target-foil is dependent on the absorption, transport and rear-side sheath conditions. Measuring the electrons escaping the target will aid in improving our understanding of these absorption processes and the rear-surface sheath fields that retard the escaping electrons and accelerate ions via the target normal sheath acceleration (TNSA) mechanism. A comprehensive Geant4 study was performed to help analyse measurements made with a wrap-around diagnostic that surrounds the target and uses differential filtering with a FUJI-film image plate detector. The contribution of secondary sources such as x-rays and protons to the measured signal have been taken into account to aid in the retrieval of the electron signal. Angular and spectral data from a high-intensity laser–solid interaction are presented and accompanied by simulations. The total number of emitted electrons has been measured as
with an estimated total energy of
Cu target with 140 J of incident laser energy during a
The excavations of the cemetery groups at Balneaves, Loanleven and Park of Tongland facilitate an examination of many aspects of Bronze Age burial practices in Scotland. They are notable as much for the differences in burial ritual they imply as for the very narrow chronological period in which they were used. The three sites produced a total of seventeen 14C dates, two of which are aberrant, with means of the remaining fifteen falling within a period of 250 years (3370–3610 bp in radiocarbon years). The excavations were sponsored by Historic Scotland (formerly Historic Buildings and Monuments, Scotland).
At Balneaves, a penannular ditch enclosed sixteen features, including a group of seven pits with cremation burials, four of which were associated with a distinctive assemblage of collared urns. The cremated bone was well preserved. At least one large standing stone had been erected on the site, and this was buried in the medieval period.
At Loanleven, only a segment of the enclosing ring-ditch survived, within which were four cists, two containing inhumations and two cremations, one of the latter (Cist 2) associated with a fragment of a food vessel. A decorated slab, in so-called ‘Passage Grave Style’, was recovered from Cist 1, and the same cist produced palynological evidence for grave furnishings in the form of a mat of plant material which probably underlay the body. 14C dates give a terminus ante quem of 3620±50 bp (GU–2543) for the re-use of the decorated slab, and a terminus post quem of 3410±50 bp (GU–2542) for the food vessel grave.
Park of Tongland, regarded as a Four-Poster stone circle, was excavated after the fall of a standing stone. It was shown to be of multi-period construction, consisting of a cairn which overlay seven pits containing fragmentary cremation burials, two associated with collared urns. The standing stones may not all have been erect at the same time. A series of 14C dates fell within the range of 1480–1530 bc.
Although usually thought of as external environmental stressors, a significant heritable component has been reported for measures of stressful life events (SLEs) in twin studies.
We examined the variance in SLEs captured by common genetic variants from a genome-wide association study (GWAS) of 2578 individuals. Genome-wide complex trait analysis (GCTA) was used to estimate the phenotypic variance tagged by single nucleotide polymorphisms (SNPs). We also performed a GWAS on the number of SLEs, and looked at correlations between siblings.
A significant proportion of variance in SLEs was captured by SNPs (30%, p = 0.04). When events were divided into those considered to be dependent or independent, an equal amount of variance was explained for both. This ‘heritability’ was in part confounded by personality measures of neuroticism and psychoticism. A GWAS for the total number of SLEs revealed one SNP that reached genome-wide significance (p = 4 × 10−8), although this association was not replicated in separate samples. Using available sibling data for 744 individuals, we also found a significant positive correlation of R2 = 0.08 in SLEs (p = 0.03).
These results provide independent validation from molecular data for the heritability of reporting environmental measures, and show that this heritability is in part due to both common variants and the confounding effect of personality.
The x-ray diffuse scattering from a single crystal of Cu3Au was measured in absolute units in a volume of reciprocal space. The measurement was made while the crystal was held at 703 K (approximately 35 K above the critical temperature for ordering) and the measured intensity was separated into components due to short range order (SRO) and strain. The Warren short range order parameters, pair interaction potentials and the first and second order static atomic displacements were obtained by Fourier inversion of these separated intensities. The relative interatomic pair potentials, out to the third shell, were found to be V2/V 1=-0.5 and V3/V 10 consistent with earlier determinations. The first order atomic pair displacements were found to be contrary to what has previously been assumed: Au-Au first neighbor pairs were found to have negative displacements on average and AuCu pairs positive displacements, compared to the average interatomic distance.
We investigate the concentration and short-range order dependence of the zero-temperature resistivity and thermopower for substitutionally disordered alloys from a first-principles approach. The alloy disorder is simulated by calculating the electronic structure of a large supercell (typically 200–250 atoms) with periodic boundary conditions. For the strong-scattering alloys we consider, the electron mean-free path is much less than the supercell dimension, causing artificial effects of periodicity to be negligible. In spite of strong scattering, there is no evidence for localized states near EF. The resistivity and thermopower are averaged over several configurations resulting in statistical error bounds of approximately ±10%. The concentration-dependent resistivity of substitutional V1−xAlx alloys agree well with Korringa-Kohn-Rostoker coherent potential approximation (KKR CPA) calculations. This confirms the accuracy of KKR CPA theory.
Diamond thin films have been synthesized at low pressures by chemical vapor deposition (CVD) and, recently, at ambient atmosphere with an oxygen-acetylene welding torch. By the application of appropriate thermal or mechanical stresses to the substrate, the diamond films can be delaminated. The delaminated films which are only a few microns thick have been fractured by manual bending. Scanning electron microscopy (SEM) examination of fractured CVD diamond films shows the presence of primarily intragranular fracture attesting to the inherent strength of the films. Using transmission electron microscopy (TEM), twinning and stacking faults are seen within the crystallites of the films along the fracture surfaces. By combining SEM and TEM examination, the relative degree of intragranular fracture found in films synthesized by both CVD and oxygen-acetylene torch has been investigated. Possible mechanisms for the intragranular fracture and the relative strength of such films are discussed.