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The role that vitamin D plays in pulmonary function remains uncertain. Epidemiological studies reported mixed findings for serum 25-hydroxyvitamin D (25(OH)D)–pulmonary function association. We conducted the largest cross-sectional meta-analysis of the 25(OH)D–pulmonary function association to date, based on nine European ancestry (EA) cohorts (n 22 838) and five African ancestry (AA) cohorts (n 4290) in the Cohorts for Heart and Aging Research in Genomic Epidemiology Consortium. Data were analysed using linear models by cohort and ancestry. Effect modification by smoking status (current/former/never) was tested. Results were combined using fixed-effects meta-analysis. Mean serum 25(OH)D was 68 (sd 29) nmol/l for EA and 49 (sd 21) nmol/l for AA. For each 1 nmol/l higher 25(OH)D, forced expiratory volume in the 1st second (FEV1) was higher by 1·1 ml in EA (95 % CI 0·9, 1·3; P<0·0001) and 1·8 ml (95 % CI 1·1, 2·5; P<0·0001) in AA (Prace difference=0·06), and forced vital capacity (FVC) was higher by 1·3 ml in EA (95 % CI 1·0, 1·6; P<0·0001) and 1·5 ml (95 % CI 0·8, 2·3; P=0·0001) in AA (Prace difference=0·56). Among EA, the 25(OH)D–FVC association was stronger in smokers: per 1 nmol/l higher 25(OH)D, FVC was higher by 1·7 ml (95 % CI 1·1, 2·3) for current smokers and 1·7 ml (95 % CI 1·2, 2·1) for former smokers, compared with 0·8 ml (95 % CI 0·4, 1·2) for never smokers. In summary, the 25(OH)D associations with FEV1 and FVC were positive in both ancestries. In EA, a stronger association was observed for smokers compared with never smokers, which supports the importance of vitamin D in vulnerable populations.
This study examined the qualitative differences between the types of strengths identified by satisfied versus distressed couples seeking a Marriage Checkup. We hypothesised that distressed couples would nominate less intimate strengths, while satisfied couples would nominate more intimate strengths. We found that distressed partners were significantly more likely to nominate items from a Parallel Support category, whereas satisfied women, but not men, were significantly more likely to nominate items from an Intimate/Affectionate category. These findings suggest that an indicator of developing couple distress is the point where couples begin to focus their attention on less emotionally vulnerable relationship aspects.
The discovery of the first electromagnetic counterpart to a gravitational wave signal has generated follow-up observations by over 50 facilities world-wide, ushering in the new era of multi-messenger astronomy. In this paper, we present follow-up observations of the gravitational wave event GW170817 and its electromagnetic counterpart SSS17a/DLT17ck (IAU label AT2017gfo) by 14 Australian telescopes and partner observatories as part of Australian-based and Australian-led research programs. We report early- to late-time multi-wavelength observations, including optical imaging and spectroscopy, mid-infrared imaging, radio imaging, and searches for fast radio bursts. Our optical spectra reveal that the transient source emission cooled from approximately 6 400 K to 2 100 K over a 7-d period and produced no significant optical emission lines. The spectral profiles, cooling rate, and photometric light curves are consistent with the expected outburst and subsequent processes of a binary neutron star merger. Star formation in the host galaxy probably ceased at least a Gyr ago, although there is evidence for a galaxy merger. Binary pulsars with short (100 Myr) decay times are therefore unlikely progenitors, but pulsars like PSR B1534+12 with its 2.7 Gyr coalescence time could produce such a merger. The displacement (~2.2 kpc) of the binary star system from the centre of the main galaxy is not unusual for stars in the host galaxy or stars originating in the merging galaxy, and therefore any constraints on the kick velocity imparted to the progenitor are poor.
We report the discovery in the Greenland ice sheet of a discrete layer of free nanodiamonds (NDs) in very high abundances, implying most likely either an unprecedented influx of extraterrestrial (ET) material or a cosmic impact event that occurred after the last glacial episode. From that layer, we extracted n-diamonds and hexagonal diamonds (lonsdaleite), an accepted ET impact indicator, at abundances of up to about 5×106 times background levels in adjacent younger and older ice. The NDs in the concentrated layer are rounded, suggesting they most likely formed during a cosmic impact through some process similar to carbon-vapor deposition or high-explosive detonation. This morphology has not been reported previously in cosmic material, but has been observed in terrestrial impact material. This is the first highly enriched, discrete layer of NDs observed in glacial ice anywhere, and its presence indicates that ice caps are important archives of ET events of varying magnitudes. Using a preliminary ice chronology based on oxygen isotopes and dust stratigraphy, the ND-rich layer appears to be coeval with ND abundance peaks reported at numerous North American sites in a sedimentary layer, the Younger Dryas boundary layer (YDB), dating to 12.9 ± 0.1 ka. However, more investigation is needed to confirm this association.
Measurements of glacier ice cliff evolution are sparse, but where they do exist, they indicate that such areas of exposed ice contribute a disproportionate amount of melt to the glacier ablation budget. We used Structure from Motion photogrammetry with Multi-View Stereo to derive 3-D point clouds for nine ice cliffs on Khumbu Glacier, Nepal (in November 2015, May 2016 and October 2016). By differencing these clouds, we could quantify the magnitude, seasonality and spatial variability of ice cliff retreat. Mean retreat rates of 0.30–1.49 cm d−1 were observed during the winter interval (November 2015–May 2016) and 0.74–5.18 cm d−1 were observed during the summer (May 2016–October 2016). Four ice cliffs, which all featured supraglacial ponds, persisted over the full study period. In contrast, ice cliffs without a pond or with a steep back-slope degraded over the same period. The rate of thermo-erosional undercutting was over double that of subaerial retreat. Overall, 3-D topographic differencing allowed an improved process-based understanding of cliff evolution and cliff-pond coupling, which will become increasingly important for monitoring and modelling the evolution of thinning debris-covered glaciers.
A few studies have evaluated the impact of clinical trial results on practice in paediatric cardiology. The Infant Single Ventricle (ISV) Trial results published in 2010 did not support routine use of the angiotensin-converting enzyme inhibitor enalapril in infants with single-ventricle physiology. We sought to assess the influence of these findings on clinical practice.
A web-based survey was distributed via e-mail to over 2000 paediatric cardiologists, intensivists, cardiothoracic surgeons, and cardiac advance practice nurses during three distribution periods. The results were analysed using McNemar’s test for paired data and Fisher’s exact test.
The response rate was 31.5% (69% cardiologists and 65% with >10 years of experience). Among respondents familiar with trial results, 74% reported current practice consistent with trial findings versus 48% before trial publication (p<0.001); 19% used angiotensin-converting enzyme inhibitor in this population “almost always” versus 36% in the past (p<0.001), and 72% reported a change in management or improved confidence in treatment decisions involving this therapy based on the trial results. Respondents familiar with trial results (78%) were marginally more likely to practise consistent with the trial results than those unfamiliar (74 versus 67%, p=0.16). Among all respondents, 28% reported less frequent use of angiotensin-converting enzyme inhibitor over the last 3 years.
Within 5 years of publication, the majority of respondents was familiar with the Infant Single Ventricle Trial results and reported less frequent use of angiotensin-converting enzyme inhibitor in single-ventricle infants; however, 28% reported not adjusting their clinical decisions based on the trial’s findings.
The Dark Energy Survey is undertaking an observational programme imaging 1/4 of the southern hemisphere sky with unprecedented photometric accuracy. In the process of observing millions of faint stars and galaxies to constrain the parameters of the dark energy equation of state, the Dark Energy Survey will obtain pre-discovery images of the regions surrounding an estimated 100 gamma-ray bursts over 5 yr. Once gamma-ray bursts are detected by, e.g., the Swift satellite, the DES data will be extremely useful for follow-up observations by the transient astronomy community. We describe a recently-commissioned suite of software that listens continuously for automated notices of gamma-ray burst activity, collates information from archival DES data, and disseminates relevant data products back to the community in near-real-time. Of particular importance are the opportunities that non-public DES data provide for relative photometry of the optical counterparts of gamma-ray bursts, as well as for identifying key characteristics (e.g., photometric redshifts) of potential gamma-ray burst host galaxies. We provide the functional details of the DESAlert software, and its data products, and we show sample results from the application of DESAlert to numerous previously detected gamma-ray bursts, including the possible identification of several heretofore unknown gamma-ray burst hosts.
Aim 1 of this study was to examine the developmental changes in typically developing English-speaking children's syntactically based sentence interpretation abilities and sensitivity to word order. Aim 2 was to determine the psychometric standing of the novel sentence interpretation task developed for this study, because we wish to use it later with children with specific language impairment. Children listened to semantically implausible sentences in which noun animacy and the natural affordance between the nouns were removed, thus controlling for event probability. Using this novel “whatdunit?” agent selection task, 256 children 7–11 years old listened to two structures with canonical word order and two with noncanonical word order. After each sentence, children selected as quickly as possible the picture of the noun they believed was “doing the action.” Children interpreted sentences with canonical word order with greater accuracy and speed than those with noncanonical word order. Older children (mean age = 10 years, 8 months) were more accurate and faster than younger children (mean age = 8 years, 1 month) across all sentence forms. Both older and younger children demonstrated similar error patterns across sentence type. The “whatdunit?” task also proved to have strong validity and reliability, making it suitable for studies with children with specific language impairment.
Recent studies on the rehabilitation of children with hydrocephalus have demonstrated the need for those planning such rehabilitation programmes to have a clear understanding of the neuropsychological and psychosocial aspects of this disorder. In an attempt to provide such information, the neuropsychological and psychosocial functioning of a group of 17 children with hydrocephalus between the ages of eight and fourteen years old was investigated. Performance by the sample with hydrocephalus was compared to that of a ‘normal’ control sample. Participants with hydrocephalus and control participants were matched on the variables of sex, age, years of education, and socio-economic status. Relative to control participants, the participants with hydrocephalus were impaired on measures of intellectual, attention, verbal and visual memory, and visuo-spatial abilities. Language alone was relatively preserved. The children with hydrocephalus also exhibited poorer self-esteem, fewer adaptive competencies, and more problem behaviours than the ‘normal’ controls. For the children with hydrocephalus, the relationship between their impaired intellectual abilities and their psychosocial functioning was investigated.
Synchrotron powder diffraction data from beamline 08B1-1 at the Canadian Light Source have been used to examine the structure of curcumin, a prime component of the Asian spice turmeric. Rigid body refinement, with the application of restraints on distances and angles, was performed with the Rietveld software package GSAS yielding monoclinic lattice parameters of a = 12.6967(1) Å, b = 7.198 52(3) Å, c = 19.9533(2) Å, and β = 95.1241(6)° (C21H20O6, Z = 4, and space group P2/n). The refinement was compared with a recent single-crystal structure and ab initio results obtained with density functional theory calculations.
Selective serotonin reuptake inhibitors (SSRIs) are considered safe and are frequently used during pregnancy. However, two case–control studies suggested an association between prenatal SSRI exposure with childhood autism.
To prospectively determine whether intra-uterine SSSRI exposure is associated with childhood autistic symptoms in a population-based study.
A total of 376 children prenatally exposed to maternal depressive symptoms (no SSRI exposure), 69 children prenatally exposed to SSRIs and 5531 unexposed children were included. Child pervasive developmental and affective problems were assessed by parental report with the Child Behavior Checklist at ages 1.5, 3 and 6. At age 6, we assessed autistic traits using the Social Responsiveness Scale (n = 4264).
Prenatal exposure to maternal depressive symptoms without SSRIs was related to both pervasive developmental (odds ratio (OR) = 1.44, 95% CI 1.07–1.93) and affective problems (OR = 1.44, 95% CI 1.15–1.81). Compared with unexposed children, those prenatally exposed to SSRIs also were at higher risk for developing pervasive developmental problems (OR = 1.91, 95% CI 1.13–3.47), but not for affective problems. Children prenatally exposed to SSRIs also had more autistic traits (B = 0.15, 95% CI 0.08–0.22) compared with those exposed to depressive symptoms only.
Our results suggest an association between prenatal SSRI exposure and autistic traits in children. Prenatal depressive symptoms without SSRI use were also associated with autistic traits, albeit this was weaker and less specific. Long-term drug safety trials are needed before evidence-based recommendations are possible.
Multi-functionalization of catalytically-active nanomaterials provides a valuable tool for enhancing reaction yield by shifting reaction equilibrium, and potentially also by adjusting reaction-diffusion kinetics. For example, multi-functionalization of mesoporous silica to make the interior pore surface hydrophobic can enhance yield in dehydration reactions. Detailed molecular-level modeling to describe the pore environment, as well as the reaction and diffusion kinetics is challenging, although we briefly discuss current strategies. Our focus, however, is on coarse-grained stochastic modeling of the overall catalytic process for highly restricted transport within narrow pores (with single-file diffusion), while accounting for a tunable interaction of the pore interior with reaction products. We show that making the pore interior unfavorable to products can significantly enhance yield due to both thermodynamic and kinetics factors.
In 2001, a report was issued by the National Research Council (NRC) entitled “Knowing What Students Know: The Science and Design of Educational Assessment” (Pellegrino, Chudowsky, & Glaser, 2001). The goal was to evaluate the state of research and theory on educational assessment and establish the scientific foundations for their design and use. As argued in that volume, many of the debates that surround educational assessment emanate from a failure to understand its fundamental nature, including the ways in which theories and models (1) of learning and knowing and (2) of measurement and statistical inference interact with and influence processes of assessment design, use, and interpretation. In this chapter we review some of the key issues regarding educational assessment raised in that report as well as examples from science, technology, engineering, and mathematics (STEM) education and educational research contexts. Our goal in explicating current understanding of the science and design of educational assessment and its applications to STEM education is to provide background knowledge that supports the effective design and use of assessment in engineering education and sharpens the focus of engineering education R&D.
In the first section we briefly introduce some key ideas critical to understanding educational assessment. This includes consideration of formal and informal uses of assessment and some conceptual issues associated with assessment design, interpretation, and use. In the second section we discuss three related conceptual frameworks about assessment that should be considered by anyone using assessment for instructional or research purposes. These include (1) assessment as a process of reasoning from evidence, (2) the use of an evidence-centered design process to develop and interpret assessments, and (3) centrality of the concept of validity in the design, use, and interpretation of any assessment. In the third section we turn to a discussion of concepts of measurement as applied to assessment and the role of statistical inference. This includes the assumptions underlying different types of psychometric models used to estimate student proficiency. The fourth section then presents applications of key ideas from the preceding sections in the form of illustrative examples of assessments used in engineering education research. In the final section we close by briefly considering the significance of a careful and thoughtful approach to assessment design, use, and interpretation in engineering education research.