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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.
Introduction: The specialist Emergency Medicine (EM) postgraduate training program at Queens University implemented a new Competency-Based Medical Education (CBME) model on July 1 2017. This occurred one year ahead of the national EM cohort, in the model of Competence By Design (CBD) as outlined by the Royal College of Physicians and Surgeons of Canada (RCPSC). This presents an opportunity to identify critical steps, successes, and challenges in the implementation process to inform ongoing national CBME implementation efforts. Methods: A case-study methodology with Rapid Cycle Evaluation was used to explore the lived experience of implementing CBME in EM at Queens, and capture evidence of behavioural change. Data was collected at 3- and 6- months post-implementation via multiple sources and methods, including: field observations, document analysis, and interviews with key stakeholders: residents, faculty, program director, CBME lead, academic advisors, and competence committee members. Qualitative findings have been triangulated with available quantitative electronic assessment data. Results: The critical processes of implementation have been outlined in 3 domain categories: administrative transition, resident transition, and faculty transition. Multiple themes emerged from stakeholder interviews including: need for holistic assessment beyond Entrustable Professional Activity (EPA) assessments, concerns about the utility of milestones in workplace based assessment by front-line faculty, trepidation that CBME is adding to, rather than replacing, old processes, and a need for effective data visualisation and filtering for assessment decisions by competency committees. We identified a need for administrative direction and faculty development related to: new roles and responsibilities, shared mental models of EPAs and entrustment scoring. Quantitative data indicates that the targeted number of assessments per EPA and stage of training may be too high. Conclusion: Exploring the lived experience of implementing CBME from the perspectives of all stakeholders has provided early insights regarding the successes and challenges of operationalizing CBME on the ground. Our findings will inform ongoing local implementation and higher-level national planning by the Canadian EM Specialty Committee and other programs who will be implementing CBME in the near future.
Introduction: Non-variceal upper gastrointestinal bleeding (NVUGIB) is a common presentation to the emergency department (ED) accounting for significant morbidity, mortality and health care resource usage. In Alberta, a provincial care pathway was recently developed to provide an evidence informed approach to managing patients with an UGIBs in the ED. Pantoprazole infusions are a commonly used treatment despite evidence that suggests they are generally not indicated prior to endoscopy in the ED. The goal of this project was to optimize management of patients with a NVUGIB, in particular reduce pre-endoscopy pantoprazole infusions. Methods: In July 2016, we implemented a multi-faceted intervention to optimize management of ED patients with NVUGIB including 1. de-emphasizing IV pantoprazole infusions in the ED, 2. clinical decision support (CDS) embedded (for endoscopy, disposition and transfusions) within the order set and 3. educating clinicians about the care pathway. We used a pre/post-order set design, analyzing 391 days pre and 189 days post-order set changes. Data was extracted from our fully integrated electronic health records system. The primary outcome was the % of patients receiving IV pantoprazole infusion ordered by an emergency physician (EP) among all patients with NVUGIB. Secondary outcomes included % transfused with hgb >70g/L and whether using the GIB order set impacted management of NVUGIB patients. Results: In the 391 days pre-order set changes, there were 2165 patients included and in the 189 days post-order set changes, there were 901 patients. For baseline characteristics, patients in the post-order set change group were significantly older (64.4 yrs vs 60.9 yrs p-value=0.0016) and had a lower hgb (115 vs 118, p-value=0.049) but otherwise for gender, measures of severity of illness (systolic blood pressure, heart rate, CTAS, % admitted) there were no significantly differences. For the primary outcome, in the pre-order set phase, 47.1% received a pantoprazole infusion ordered by an EP, compared to 31.5% in the post-order phase, for an absolute reduction of 15.6% (p-value= <0.001). For the secondary outcomes, transfusion rates were similar pre/post (22.08% vs 22.75%). Significant inter-site variability exists with respect to the reduction in pantoprazole infusion rates across the four sites (-23.3% to +6.12%). Conclusion: Our interventions resulted in a significant overall reduction in pantoprazole infusions in ED patients with NVUGIB. Reductions in pantoprazole infusions varied significantly across the different sites, future work in our department will explore and address this variability. Keys to the success of this project included engaging clinicians as well as leveraging the SCM order sets as well as the provincial care pathway. Although there were no changes in transfusion rates, it in unclear if this a function of the CDS not being effective or whether these transfusions were clinically indicated.
Vase-shaped microfossils (VSMs) occur in dolomitic extraclasts of indeterminate provenance within the basal diamictite of the Neoproterozoic Urucum Formation (Jacadigo Group) of west-central Brazil, having an age constrained between 889±44 Ma (K-Ar; basement rocks) and 587±7 Ma (40Ar/39Ar age of early metamorphic cryptomelane in overlying manganese ore). Early isopachous carbonate cement entombed these VSMs, preserving rare direct evidence of original wall composition that is carbonaceous (now kerogenous) in practically all specimens. Some tests are siliceous or composed of a quartz-kerogen mixture; secondary replacement explains some features of these tests, but original biomineralization seems more likely for others. This interpretation, coupled with test morphology, suggests affinity to arcellinid testate amoebae. Five VSM taxa are recognized in the deposit: Cycliocyrillium simplex Porter, Meisterfeld, and Knoll, 2003, and C. torquata Porter, Meisterfeld, and Knoll, 2003, originally described in the Chuar Group (USA), and three new monospecific genera—Palaeoamphora urucumense n. gen. n. sp., Limeta lageniformis n. gen. n. sp., and Taruma rata n. gen. n. sp. Most of the taxonomically important characteristics of these VSMs occur also in extant testate amoebae, but the combinations of some characters, such as organic-walled tests having exceptionally long necks that exhibit terminal apertures (L. lageniformis n. gen. n. sp.), are evidently novel additions to the known diversity of Neoproterozoic VSMs. Evidence of glacially influenced deposition in the conformably overlying Santa Cruz Formation may indicate that the Urucum Formation slightly preceded or was penecontemporaneous with a major Neoproterozoic glaciation, although the VSM-hosting extraclasts must be older, possibly rivaling the age of the testate amoebae of the Chichkan Formation (766±7 Ma) that are currently regarded as the oldest record of protists in the geological record.
We conducted infrared spectroscopic observations of bright stars in the direction of the molecular clouds W33 and GMC G23.3 − 0.3. We compared stellar spectro-photometric distances with parallactic distances to these regions, and we were able to assess the association of the detected massive stars with these molecular complexes. The spatial and temporal distributions of the detected stars enabled us to locate sources of ionizing radiation and to gather precise information on the star formation history of these clouds. The studied clouds present different distributions of massive stars.
We use the wide-field capabilities of the 2 degree field fibre positioner and the AAOmega spectrograph on the Anglo-Australian Telescope (AAT) to obtain redshifts of galaxies that hosted supernovae during the first 3 years of the Supernova Legacy Survey (SNLS). With exposure times ranging from 10 to 60 ks per galaxy, we were able to obtain redshifts for 400 host galaxies in two SNLS fields, thereby substantially increasing the total number of SNLS supernovae with host galaxy redshifts. The median redshift of the galaxies in our sample that hosted photometrically classified Type Ia supernovae (SNe Ia) is z ~ 0.77, which is 25% higher than the median redshift of spectroscopically confirmed SNe Ia in the 3-year sample of the SNLS. Our results demonstrate that one can use wide-field fibre-fed multi-object spectrographs on 4-m telescopes to efficiently obtain redshifts for large numbers of supernova host galaxies over the large areas of the sky that will be covered by future high-redshift supernova surveys, such as the Dark Energy Survey.
Among US racial/ethnic minority women, we examined associations between maternal experiences of racial discrimination and child growth in the first 3 years of life. We analyzed data from Project Viva, a pre-birth cohort study. We restricted analyses to 539 mother–infant pairs; 294 were Black, 127 Hispanic, 110 Asian and 8 from additional racial/ethnic groups. During pregnancy, mothers completed the Experiences of Discrimination survey that measured lifetime experiences of racial discrimination in diverse domains. We categorized responses as 0, 1–2 or ⩾3 domains. Main outcomes were birth weight for gestational age z-score; weight for age (WFA) z-score at 6 months of age; and at 3 years of age, body mass index (BMI) z-score. In multivariable analyses, we adjusted for maternal race/ethnicity, nativity, education, age, pre-pregnancy BMI, household income and child sex and age. Among this cohort of mostly (58.2%) US-born and economically non-impoverished mothers, 33% reported 0 domains of discrimination, 33% reported discrimination in 1–2 domains and 35% reported discrimination in ⩾3 domains. Compared with children whose mothers reported no discrimination, those whose mothers reported ⩾3 domains had lower birth weight for gestational age z-score (β −0.25; 95% CI: −0.45, −0.04), lower 6 month WFA z-score (β −0.34; 95% CI: −0.65, −0.03) and lower 3-year BMI z-score (β −0.33; 95% CI: −0.66, 0.00). In conclusion, we found that among this cohort of US racial/ethnic minority women, mothers’ report of experiencing lifetime discrimination in ⩾ 3 domains was associated with lower fetal growth, weight at 6 months and 3-year BMI among their offspring.
Preterm birth affects over 12% of all infants born in the United States; yet the biology of early delivery remains unclear, including whether epigenetic mechanisms are involved. We examined associations of maternal and umbilical cord blood long interspersed nuclear element-1 (LINE-1) DNA methylation with length of gestation and odds of preterm birth in singleton pregnancies in Project Viva. In white blood cells from maternal blood during first trimester (n = 914) and second trimester (n = 922), and from venous cord blood at delivery (n = 557), we measured LINE-1 by pyrosequencing [expressed as %5 methyl cytosines within the LINE-1 region analyzed (%5mC)]. We ran linear regression models to analyze differences in gestation length, and logistic models for odds of preterm birth (<37 v. ⩾37 weeks’ gestation), across quartiles of LINE-1. Mean (s.d.) LINE-1 levels were 84.3 (0.6), 84.5 (0.4) and 84.6 (0.7) %5mC for first trimester, second trimester and cord blood, respectively. Mean (s.d.) gestational age was 39.5 (1.8) weeks, and 6.5% of infants were born preterm. After adjustment for maternal age, race/ethnicity, body mass index, education, smoking status and fetal sex, women with the highest v. lowest quartile of first trimester LINE-1 had longer gestations [0.45 weeks (95% CI 0.12, 0.78)] and lower odds of preterm birth [OR 0.40 (0.17, 0.94)], whereas associations with cord blood LINE-1 were in the opposite direction (−0.45 weeks, −0.83, −0.08) and [OR 4.55 (1.18, 17.5)]. In conclusion, higher early pregnancy LINE-1 predicts lower risk of preterm birth. In contrast, preterm birth is associated with lower LINE-1 in cord blood.
This study assessed risk factors for respiratory syncytial virus (RSV) hospitalization and disease severity in Wellington, New Zealand. During the southern hemisphere winter months of 2003–2005, 230 infants aged <24 months hospitalized with bronchiolitis were recruited. RSV was identified in 141 (61%) infants. Comparison with data from all live hospital births from the same region (2003–2005) revealed three independent risk factors for RSV hospitalization: birth between February and July [adjusted risk ratio (aRR) 1·62, 95% confidence interval (CI) 1·15–2·29], gestation <37 weeks (aRR 2·29, 95% CI 1·48–3·56) and Māori ethnicity (aRR 3·64, 95% CI 2·27–5·85) or Pacific ethnicity (aRR 3·60, 95% CI 2·14–6·06). The high risk for Māori and Pacific infants was only partially accounted for by other known risk factors. This work highlights the importance of RSV disease in indigenous and minority populations, and identifies the need for further research to develop public health measures that can reduce health disparities.
Amnestic mild cognitive impairment (aMCI) represents a high-risk
factor for Alzheimer's disease (AD) and is characterized by a
selective decline in episodic memory. Although by definition aMCI is not
associated with impaired verbal fluency performance, we examined relative
differences between fluency tasks because AD is characterized by poorer
semantic than phonemic fluency. Phonemic and semantic fluency trials were
administered to 46 healthy controls, 33 patients with aMCI, and 33
patients with AD. Results revealed a progressive advantage (controls >
aMCI > AD) in semantic, relative to phonemic fluency. Difference scores
between tasks distinguished each group from the others with medium to
large effect sizes (d) ranging from 0.49 to 1.07. Semantic
fluency relies more on semantic associations between category exemplars
than does phonemic fluency. This aMCI fluency pattern reflects degradation
of semantic networks demonstrating that initial neuropathology may extend
beyond known early changes in hippocampal regions. (JINS, 2006,
12, 570–574.)The data were
collected in accordance with the guidelines of the Helsinki Declaration
and approved by the Research Ethics and Scientific Review Committee of
Baycrest Centre. This is an original submission. Portions of these data
were presented at the annual meeting of the International
Neuropsychological Society, February 2005, St. Louis, Missouri. There is
no conflict of interest.
The temperature dependence of the cathodoluminescence (CL) originating from In0.21Ga0.79As/GaAs multiple quantum wells has been studied between 86 and 250 K. The CL intensity exhibits an Arrenhius-type dependence on temperature (T), characterized by two different activation energies. The spatial variations in activation energy caused by the presence of interfacial misfit dislocations is examined. The CL intensity dependence on temperature for T ≲ 150 K is controlled by thermally activated nonradiative recombination. For T ≳ 150 K the decrease in CL intensity is largely influenced by thermal re-emission of carriers out of the quantum wells.
Linearly polarized cathodoluminescence (LPCL) imaging and spectroscopy techniques have been employed to examine the optical properties and homogeneity of (InP)2/(GaP)2 bilayer superlattice (BSL) structures which exhibit a lateral composition modulation that leads to the formation of quantum wires. LPCL spectra were measured for various temperature and electron beam excitation densities. The magnitude of the polarization anisotropy and spectral lineshape are found to depend sensitively on the excitation conditions, revealing large nonlinear optical effects in these samples. CL images reveal that defects in the bilayer superlattice structure originate from the GaAs substrate or the initial stages of InGaP growth.
The effects of strain-induced defects on excess carrier lifetime and transport in a nipi-doped In0.2Ga0.8As/GaAs multiple quantum well (MQW) structure were examined with a new method called electron beam-induced absorption modulation (EBIA) in which the kinetics of carrier transport and recombination are examined with a high-spatial, -spectral and -temporal resolution. The excess carrier lifetime and ambipolar diffusion were found to be reduced by factors of ∼1013 and ∼103 compared to theoretical values, respectively, and this is attributed to the presence of strain-induced defects. The MQW excitonic absorption coefficient sensitively depends on the carrier density in the QWs, as a result of screening of the electron-hole (e-h) Coulombic interaction. Likewise, ambipolar diffusion is found to depend on the excess carrier density in a nonlinear fashion, as a result of the e-h plasma-induced changes in the local depletion widths in the vicinity of structural defects.
The potential of realizing quantum box structures via in-situ molecular beam epitaxical growth on the (111)B face of GaAs is explored. Growth is carried out on patterned (111)3B substrates with an array of truncated triangular pyramidal mesas. The mesa tops with arbitrarily small areal dimensions are used as templates for quantum box realization. Under appropriate conditions of growth along with the attendant interfacet migration, a mesa top growth profile characterized by monotonically shrinking lateral dimensions resulting in 'pinch-off is achieved.
The GALLEX collaboration aims at the detection of solar neutrinos in a radiochemical experiment employing 30 tons of Gallium in form of concentrated aqueous Gallium-chloride solution. The detector is primarily sensitive to the otherwise inaccessible pp-neutrinos. Details of the experiment have been repeatedly described before [1-7]. Here we report the present status of implementation in the Laboratori Nazionali del Gran Sasso (Italy). So far, 12.2 tons of Gallium are at hand. The present status of development allows to start the first full scale run at the time when 30 tons of Gallium become available. This date is expected to be January, 1990.