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Environmental factors such as sunshine hours, temperature and UV radiation (UVR) are known to influence seasonal fluctuations in vitamin D concentrations. However, currently there is poor understanding regarding the environmental factors or individual characteristics that best predict neonatal 25-hydroxyvitamin D (25(OH)D) concentrations. The aims of this study were to (1) identify environmental and individual determinants of 25(OH)D concentrations in newborns and (2) investigate whether environmental factors and individual characteristics could be used as proxy measures for neonatal 25(OH)D concentrations. 25-Hydroxyvitamin D3 (25(OH)D3) was measured from neonatal dried blood spots (DBS) of 1182 individuals born between 1993 and 2002. Monthly aggregated data on daily number of sunshine hours, temperature and UVR, available from 1993, were retrieved from the Danish Meteorological Institute. The individual predictors were obtained from the Danish National Birth register, and Statistics Denmark. The optimal model to predict 25(OH)D3 concentrations from neonatal DBS was the one including the following variables: UVR, temperature, maternal education, maternal smoking during pregnancy, gestational age at birth and parity. This model explained 30 % of the variation of 25(OH)D3 in the neonatal DBS. Ambient UVR in the month before the birth month was the best single-item predictor of neonatal 25(OH)D3, accounting for 24 % of its variance. Although this prediction model cannot substitute for actual blood measurements, it might prove useful in cohort studies ranking individuals in groups according to 25(OH)D3 status.
Hill (Twin Research and Human Genetics, Vol. 21, 2018, 84–88) presented a critique of our recently published paper in Cell Reports entitled ‘Large-Scale Cognitive GWAS Meta-Analysis Reveals Tissue-Specific Neural Expression and Potential Nootropic Drug Targets’ (Lam et al., Cell Reports, Vol. 21, 2017, 2597–2613). Specifically, Hill offered several interrelated comments suggesting potential problems with our use of a new analytic method called Multi-Trait Analysis of GWAS (MTAG) (Turley et al., Nature Genetics, Vol. 50, 2018, 229–237). In this brief article, we respond to each of these concerns. Using empirical data, we conclude that our MTAG results do not suffer from ‘inflation in the FDR [false discovery rate]’, as suggested by Hill (Twin Research and Human Genetics, Vol. 21, 2018, 84–88), and are not ‘more relevant to the genetic contributions to education than they are to the genetic contributions to intelligence’.
Studies have suggested that vitamin D status at birth may be associated with a range of neonatal outcomes. The aim of this study was to assess the association between neonatal 25-hydroxyvitamin D3 (25(OH)D3) concentration and gestational age, birth weight, Ponderal Index and size for gestational age. Neonatal capillary blood stored as dried blood spots was used to assess 25(OH)D3 concentrations among 2686 subjects selected from a random population sub-sample of individuals, born in Denmark from 1 May 1981 to 31 December 2002. There was an inverse association between 25(OH)D3 concentration and gestational age at birth of −0·006 (95 % CI −0·009, −0·003, P<0·001) weeks of gestation per 1 nmol/l increase in 25(OH)D3 concentration. An inverted U-shaped association between 25(OH)D3 and birth weight and Ponderal Index (P=0·04) was found, but no association with size for gestational age was shown. This study suggests that neonatal 25(OH)D3 concentration is associated with anthropometric measures at birth known to be correlated with many subsequent health outcomes such as obesity and type 2 diabetes.
Brittle ice, which occurs in all intermediate-depth and deep ice cores retrieved from high-latitude regions, presents a challenge for high-resolution measurements of water isotopes, gases, ions and other quantities conducted with continuous flow analysis (CFA). We present a novel method of preserving brittle ice for CFA stable water isotope measurements using data from a new ice core recovered by the Roosevelt Island Climate Evolution (RICE) project. Modest modification of the drilling technique and the accommodation of non-horizontal fractures (‘slanted breaks’) in processing led to a substantial improvement in the percentage of brittle ice analyzed with CFA (87.8%). Whereas traditional processing methods remove entire fragmented pieces of ice, our method allowed the incorporation of a total of 3 m of ice (1% of the 261 m of brittle ice and ~1300 years of climate history) that otherwise would not have been available for CFA. Using the RICE stable water isotope CFA dataset, we demonstrate the effect of slanted breaks and analyze the resulting smoothing of the data with real and simulated examples. Our results suggest that retaining slanted breaks are a promising technique for preserving brittle ice material for CFA stable water isotope measurements.
This study determines the prevalence of inadequate micronutrient intakes consumed by long-term care (LTC) residents. This cross-sectional study was completed in thirty-two LTC homes in four Canadian provinces. Weighed and estimated food and beverage intake were collected over 3 non-consecutive days from 632 randomly selected residents. Nutrient intakes were adjusted for intra-individual variation and compared with the Dietary Reference Intakes. Proportion of participants, stratified by sex and use of modified (MTF) or regular texture foods, with intakes below the Estimated Average Requirement (EAR) or Adequate Intake (AI), were identified. Numbers of participants that met these adequacy values with use of micronutrient supplements was determined. Mean age of males (n 197) was 85·2 (sd 7·6) years and females (n 435) was 87·4 (sd 7·8) years. In all, 33 % consumed MTF; 78·2 % (males) and 76·1 % (females) took at least one micronutrient pill. Participants on a MTF had lower intake for some nutrients (males=4; females=8), but also consumed a few nutrients in larger amounts than regular texture consumers (males=4; females =1). More than 50 % of participants in both sexes and texture groups consumed inadequate amounts of folate, vitamins B6, Ca, Mg and Zn (males only), with >90 % consuming amounts below the EAR/AI for vitamin D, E, K, Mg (males only) and K. Vitamin D supplements resolved inadequate intakes for 50–70 % of participants. High proportions of LTC residents have intakes for nine of twenty nutrients examined below the EAR or AI. Strategies to improve intake specific to these nutrients are needed.
The hydrological ice-sheet basin draining into the Tasersiaq lake, West Greenland (66°13’ N, 50°30’W), was delineated, first using standard digital elevation models (DEMs) for ice-sheet surface and bedrock, and subsequently using a new high-resolution dataset, with a surface DEM derived from repeat-track interferometric synthetic aperture radar (SAR) and a bedrock topography derived from an airborne 60 MHz ice-penetrating radar. The extent of the delineation was calculated from a water-pressure potential as a function of the ice-sheet surface and bedrock elevations and a hydraulic factor k describing the relative importance of the potential of the ice overburden pressure compared to the bedrock topography. Themeltwater run-off for the basin delineations was modelled with an energy-balance model calibrated with observed ice-sheet ablation and compared to a 25 year time series of measured basin run-off. The standard DEMs were found to be inadequate for delineation purposes, whereas delineations from high-resolution data were found to be very sensitive to changes in k in a non-linear way, causing a factor 5 change of basin area, corresponding to a doubling of the modelled runoff. The 50% standard deviation of the measured basin run-off could thus be explained by small year-to-year variations of the k-factor.
Surface strain rates around the southeastern dome of Hans Tausen Iskappe in Peary Land, North Greenland (82.5° N, 27.5° W), are determined from global positioning system surveys of a strain net. Average longitudinal surface strain rate increases towards the dome, from (1.4 ± 0.2) × 10−4 a−1 at 5–10 ice thicknesses from the divide to (2.4 ± 1.0) × 10−4 a−1 within 1 ice thickness from the divide. Analysis of the data shows that the ice cap is presently building up within the strain net with an average rate of 〈∂H/∂t〉 = + 0.04 ± 0.02 m a−1. Assuming a uniform thickening, the shape factor of the horizontal velocity (the ratio between the vertically averaged horizontal velocity and the horizontal surface velocity) decreases towards the dome, from 0.9 at a distance of 10 ice thicknesses from the dome to 0.5 at the dome based on application of the continuity equation. Our results indicate that a region with anomalous flow is formed around the dome, supporting recent indications reported by Vaughan and others (1999). It is not possible from our data to constrain parameters of the flow law, because there is no independent estimate of the significant present thickening of the central part of the ice cap and its pattern around the dome.
To assess hospital surgical-site infection (SSI) identification and reporting following colon surgery and abdominal hysterectomy via a statewide external validation
Infection preventionists (IPs) from the California Department of Public Health (CDPH) performed on-site SSI validation for surgical procedures performed in hospitals that voluntarily participated. Validation involved chart review of SSI cases previously reported by hospitals plus review of patient records flagged for review by claims codes suggestive of SSI. We assessed the sensitivity of traditional surveillance and the added benefit of claims-based surveillance. We also evaluated the positive predictive value of claims-based surveillance (ie, workload efficiency).
Upon validation review, CDPH IPs identified 239 SSIs following colon surgery at 42 hospitals and 76 SSIs following abdominal hysterectomy at 34 hospitals. For colon surgery, traditional surveillance had a sensitivity of 50% (47% for deep incisional or organ/space [DI/OS] SSI), compared to 84% (88% for DI/OS SSI) for claims-based surveillance. For abdominal hysterectomy, traditional surveillance had a sensitivity of 68% (67% for DI/OS SSI) compared to 74% (78% for DI/OS SSI) for claims-based surveillance. Claims-based surveillance was also efficient, with 1 SSI identified for every 2 patients flagged for review who had undergone abdominal hysterectomy and for every 2.6 patients flagged for review who had undergone colon surgery. Overall, CDPH identified previously unreported SSIs in 74% of validation hospitals performing colon surgery and 35% of validation hospitals performing abdominal hysterectomy.
Claims-based surveillance is a standardized approach that hospitals can use to augment traditional surveillance methods and health departments can use for external validation.
Using an active transponder with the ERS-I and ERS-2 radar altimeters, the distance to the satellite was measured at a location close to the GRIP site, Greenland, at an altitude of 3.2 km. The measurement was executed while the transponder was in the “ice-tracking mode”. It includes a bias due to the propagation delay. The location of the transponder was determined using the global positioning system.
The transponder signal was modeled and the distance from the altimeter to the effective reflection point of the transponder was determined. Since the transponder was located within 1 km of the ground tracks, the measurement was corrected for this offset. A correction was also done for the surface slope, resulting in the distance (plus bias) to the closest sub-satellite point on the surface of the (compact) snow.
The transponder signal was then removed from the radar altimeter waveform, enabling the determination of the distance (plus bias from the altimeter to the first reflective surface within the snow. The différence between this distance and that obtained using the transponder was < 2 m. This shows that the surface which gives rise to the first return of the reflection agrees with the surface of the (compact, dry) snow at this high-altitude location. This is an important result to be used when studying ice-cap topography using satellite radar altimetry.
This prospective cohort study was conducted in eighteen Canadian hospitals with the aim of examining factors associated with nutritional decline in medical and surgical patients. Nutritional decline was defined based on subjective global assessment (SGA) performed at admission and discharge. Data were collected on demographics, medical information, food intake and patients’ satisfaction with nutrition care and meals during hospitalisation; 424 long-stay (≥7 d) patients were included; 38 % of them had surgery; 51 % were malnourished at admission (SGA B or C); 37 % had in-hospital changes in SGA; 19·6 % deteriorated (14·6 % from SGA A to B/C and 5 % from SGA B to C); 17·4 % improved (10·6 % from SGA B to A, 6·8 % from SGA C to B/A); and 63·0 % patients were stable (34·4 % were SGA A, 21·3 % SGA B, 7·3 % SGA C). One SGA C patient had weight loss ≥5 %, likely due to fluid loss and was designated as stable. A subset of 364 patients with admission SGA A and B was included in the multiple logistic regression models to determine factors associated with nutritional decline. After controlling for SGA at admission and the presence of a surgical procedure, lower admission BMI, cancer, two or more diagnostic categories, new in-hospital infection, reduced food intake, dissatisfaction with food quality and illness affecting food intake were factors significantly associated with nutritional decline in medical patients. For surgical patients, only male sex was associated with nutritional decline. Factors associated with nutritional decline are different in medical and surgical patients. Identifying these factors may assist nutritional care.
The incidence of invasive infections due to Neisseria meningitidis in Israel is about 1/100 000 population annually. Three cases of meningococcal meningitis were reported in employees at a single plant; the first case appeared in March 2013 and the second and third cases appeared in December, almost 9 months later. N. meningitidis serogroup B was isolated from cerebrospinal fluid samples. Multilocus sequence typing assigned the three meningococcal isolates to ST10418, a new sequence type and a member of the ST32 clonal complex. The clonality was confirmed by performance of pulsed-field gel electrophoresis. Post-exposure antibiotic prophylaxis was administered to close contacts of the first case. Upon the diagnosis of the additional two cases, post-exposure prophylaxis was administered to all the plant employees. This report demonstrates the importance of combining public health measures and advanced laboratory studies to confirm clonality and to prevent further disease spread in a closed setting.
Lateral epitaxial overgrowth (LEO) on Si(111) substrates using an AlN buffer layer is demonstrated and characterized using scanning electron microscopy, atomic force microscopy, transmission electron microscopy, x-ray diffraction, photoluminescence spectroscopy, and cathodoluminescence imaging. The <100>-oriented LEO GaN stripes grown on silicon substrates are shown to have similar structural properties as LEO GaN grown on GaN/Al2O3 substrates: the surface topography is characterized by continuous crystallographic steps rather than by steps terminated by screw-component threading dislocations; the density of threading dislocations is <106 cm−2; the LEO regions exhibit crystallographic tilt (0.7-4.7°) relative to the seed region. The AlN buffer thickness affects the stripe morphology and, in turn, the microstructure of the LEO GaN. The issues of chemical compability and thermal expansion mismatch are discussed.
This work presents a systematic study that evaluates the feasibility and reliability of local band gap measurements of Cu(In,Ga)Se2 thin films by valence electron energy-loss spectroscopy (VEELS). The compositional gradients across the Cu(In,Ga)Se2 layer cause variations in the band gap energy, which are experimentally determined using a monochromated scanning transmission electron microscope (STEM). The results reveal the expected band gap variation across the Cu(In,Ga)Se2 layer and therefore confirm the feasibility of local band gap measurements of Cu(In,Ga)Se2 by VEELS. The precision and accuracy of the results are discussed based on the analysis of individual error sources, which leads to the conclusion that the precision of our measurements is most limited by the acquisition reproducibility, if the signal-to-noise ratio of the spectrum is high enough. Furthermore, we simulate the impact of radiation losses on the measured band gap value and propose a thickness-dependent correction. In future work, localized band gap variations will be measured on a more localized length scale to investigate, e.g., the influence of chemical inhomogeneities and dopant accumulations at grain boundaries.