IntroductionThis study will test the effectiveness of FIT Families (FIT), a multicomponent family-based behavioural intervention, against a credible attention control condition, Home-Based Family ...Support (HBFS). This protocol paper describes the design of a randomised clinical trial testing the efficacy of the FIT intervention. The protocol will assess the efficacy of FIT to improve health status in African American adolescents with obesity (AAAO) and their primary caregivers on primary (percent body fat) and secondary (physical activity, metabolic control, weight loss) outcomes and its cost-effectiveness.Methods180 youth/caregiver dyads are randomised into FIT or HBFS, stratified by age, gender and baseline per cent overweight. The proposed study follows a two condition (FIT, HBFS) by four assessment time points. Tests will be conducted to identify potential relationship of baseline demographic and clinical variables to our dependent variables and see whether they are balanced between groups. It is hypothesised that youth/caregiver dyads randomised to FIT will show significantly greater reductions in percent body fat over a 12-month follow-up period compared with AAAO receiving HBFS. Preliminary findings are expected by November 2023.EthicsThis protocol received IRB approval from the Medical University of South Carolina (Pro00106021; see ‘MUSC IRB 106021 Main Approval.doxc’ in online supplemental materials).DisseminationDissemination activities will include summary documents designed for distribution to the broader medical community/family audience and submission of manuscripts, based on study results, to relevant peer-reviewed scientific high-impact journals.Trial registration numberNCT04974554.
Oxygen Isotopes and the Moon-Forming Giant Impact Wiechert, U.; Halliday, A. N.; D.-C. Lee ...
Science (American Association for the Advancement of Science),
10/2001, Letnik:
294, Številka:
5541
Journal Article
Recenzirano
We have determined the abundances of16O,17O, and18O in 31 lunar samples from Apollo missions 11, 12, 15, 16, and 17 using a high-precision laser fluorination technique. All oxygen isotope ...compositions plot within ±0.016 per mil (2 standard deviations) on a single mass-dependent fractionation line that is identical to the terrestrial fractionation line within uncertainties. This observation is consistent with the Giant Impact model, provided that the proto-Earth and the smaller impactor planet (named Theia) formed from an identical mix of components. The similarity between the proto-Earth and Theia is consistent with formation at about the same heliocentric distance. The three oxygen isotopes (Δ17O) provide no evidence that isotopic heterogeneity on the Moon was created by lunar impacts.
Abstract Objectives To compare carotid endarterectomy with carotid artery stenting in the prevention of stroke in patients with asymptomatic carotid stenosis. Design A large, simple, pragmatic ...international trial of at least 5000 patients with asymptomatic carotid stenosis in whom intervention is thought to be needed but where there is substantial uncertainty about the appropriate choice of treatment. The trial is designed to fit in easily with normal clinical practice. Materials & Methods A short (∼2 min) telephone call is made to randomise patients to either carotid endarterectomy (CEA) or stenting (CAS). Follow-up by the collaborator will be at one month after the procedure (simple 1-page form) and by the ACST office for 5-years post-procedure. Data will be analysed on an intention-to-treat basis; main outcomes will be 30-day myocardial infarction, stroke and death, and 5-year stroke rates. In addition, appropriate subgroup analyses will be undertaken, and health economic evaluation will consider procedural and stroke-related healthcare costs and quality of life. Conclusion Collaborators who routinely undertake CEA and CAS are encouraged to participate in ACST-2. This trial, now funded and open for randomisation, will provide important evidence comparing the immediate and long-term safety and efficacy of carotid endarterectomy and stenting in patients with asymptomatic carotid stenosis.
For nearly half a century, M.A.K. Halliday has been enriching the discipline of linguistics with his keen insight into this social semiotic phenomenon we call language. This series presents his ...collected works.
Thought always exaggerates' Hannah Arendt writes. The question of exaggeration becomes a philosophical question when thought endeavours to clarify the ways in which it relates to limits. If its ...disclosing force depends on exaggeration, so does the;confusion to which it can;fall prey. This book analyses concepts such as truth and trust, practices such as politics and art, experiences such as the formation of a life line and its erasure, from the viewpoint of exaggeration.
Arising from F. Albarède Nature 461, 1227-1233 (2009)It has long been thought that the Earth had a protracted and complex history of volatile accretion and loss. Albarède paints a different picture, ...proposing that the Earth first formed as a dry planet which, like the Moon, was devoid of volatile constituents. He suggests that the Earth's complement of volatile elements was only established later, by the addition of a small veneer of volatile-rich material at ∼100 Myr (here and elsewhere, ages are relative to the origin of the Solar System). Here we argue that the Earth's mass balance of moderately volatile elements is inconsistent with Albarède's hypothesis but is well explained by the standard model of accretion from partially volatile-depleted material, accompanied by core formation.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Abstract Objective To assess the association between 25-hydroxyvitamin D (25OHD) status and obesity, cardiovascular diseases (CVDs), the metabolic syndrome, and type 2 diabetes mellitus (T2DM) in ...ethnic minorities. Methods Databases searched were CINHAL with full text, Global Health, MEDLINE with full text, and PsycINFO from 1980 through 2010 (February). Studies were included if they 1) targeted immigrants from low- to high-income countries or ethnic minorities, 2) focused primarily on 25(OH)D and its relation to obesity, T2DM, and/or CVDs, and 3) were published in peer-reviewed journals. The influences of key confounders such as age, gender, and ethnicity on any observed relations were also assessed. Due to the heterogeneity of study characteristics, only a narrative synthesis was undertaken. Results Ethnic minorities had significantly higher rates of vitamin D insufficiency (25OHD <50 nmol/L; children 43.6–48.7% versus 10%; adults 30.3–53% versus 13.7–26%) than their white counterparts. None of the studies reported a prevalence of obesity stratified by ethnicity. There was evidence supporting links between vitamin D deficiency and obesity-related chronic diseases, with 14 of 14 studies reporting a statistically significant result with a measurement of obesity, four of five for T2DM, four of five for CVDs, and one of one for the metabolic syndrome. However, the strength of the association varied across ethnic groups depending on the index used to measure adiposity, T2DM, and CVDs. Because most of the included studies were cross-sectional and there were variations in outcome measurements, it was not possible to determine the relative contributions of obesity or vitamin D insufficiency to CVD risk and risk of T2DM or which is the initial driver It is possible both have a role to play. Conclusion Further research specific to migrant populations using randomized controlled trials are required to establish whether causal links between 25(OH)D and obesity-related chronic disease exist, and whether vitamin D supplementation could be valuable in the prevention or treatment of obesity-related diseases.
Objective/Background On ultrasound, potentially “high risk” carotid plaques may appear echolucent. In this study, whether a confident classification of echolucent plaque was a predictor of future ...ipsilateral ischaemic stroke in asymptomatic patients randomized to medical therapy in the Asymptomatic Carotid Surgery Trial-1 (ACST-1) was assessed. Methods We performed a post-hoc analysis of 814 ACST-1 patients randomized to medical therapy alone with baseline plaque assessment classified as definitely echolucent (> 25% soft plaque) or nonecholucent (< 25% soft plaque). Kaplan–Meier survival curves were used to compare cumulative rates of ipsilateral ischaemic stroke in both groups. Results In the first 5 years after randomization, a significantly higher risk of ipsilateral stroke was observed in patients with definitely echolucent plaques (8.0%; 95% confidence interval CI 6.4–9.6) when compared with patients with definitely nonecholucent plaques (3.1%; 95% CI 2.1–4.1; p = .009). After adjustments for other risk factors, plaque echolucency was associated with a 2.5-times increased risk of ipsilateral ischaemic stroke (hazard ratio 2.52; 95% CI 1.20–5.25; p = .014). Use of lipid-lowering therapy was low in both groups during the first 5 years after randomization but rose sharply during years 5–10 of follow-up, and was significantly more likely to be prescribed for patients with echolucent plaques ( p = .001). The risk of ipsilateral ischaemic stroke at 10 years was similar for both groups of patients ( p = .233). Conclusion Although the numbers of events in this study was low, definite plaque echolucency (> 25% soft plaque) was associated with a higher 5-year ipsilateral stroke risk in ACST-1 and may therefore help to identify patients at increased risk of stroke for whom carotid intervention may be particularly beneficial.
Magnesium (Mg) stable isotopes are increasingly used as a weathering proxy in soils and rivers, but the impact of the mineralogy of secondary phases on isotope fractionation remains obscure. A better ...understanding of the behaviour of Mg isotopes during weathering processes is a mandatory step toward deployment of this new tracer for understanding chemical fluxes exported from the critical zone. Here we investigate isotopic variations in δ26Mg in bulk soils and clay fractions relative to their parent andesite in three soil weathering sequences from Guadeloupe formed under contrasting climatic conditions. Soils formed in drier conditions (low precipitation) contain smectite, whereas soils formed under wet conditions (high rainfall) are characterized by halloysite and Fe-oxides or kaolinite.
All clay fractions have Mg isotopic compositions (δ26Mg −0.41‰ to −0.10‰) similar to or heavier than their parent andesite (δ26Mg −0.47‰) supporting the preferential incorporation of heavy Mg isotopes in secondary Mg-bearing clay minerals with the first direct measurements on clay fractions. Soils with lighter Mg isotope compositions have greater quantities of exchangeable Mg. The data support a contribution from sea spray to the exchangeable Mg pool correlated to the soil weathering degree. This study highlights for the first time that the soil δ26Mg not only depend on δ26Mg of the parent rock, and on any fractionation that might occur, but also on the Mg retention on the exchange complex, which could in turn be controlled by external inputs such as sea spray.
► Incorporation of heavy Mg isotopes in secondary clay minerals relative to the andesite. ► A greater amount of exchangeable Mg relates to lighter Mg isotope compositions of soils. ► Contribution from sea spray to the exchangeable Mg and the Mg isotope budget. ► Contribution to identify the processes controlling Mg isotope variations with weathering.
We present a comparison of fast-response instruments installed onboard the NASA DC-8 aircraft that measured nitrogen oxides (NO and NO2), nitrous acid (HONO), total reactive odd nitrogen (measured ...both as the total (NOy) and from the sum of individually measured species (ΣNOy)), and carbon monoxide (CO) in the troposphere during the 2019 Fire Influence on Regional to Global Environments and Air Quality (FIREX-AQ) campaign. By targeting smoke from summertime wildfires, prescribed fires, and agricultural burns across the continental United States, FIREX-AQ provided a unique opportunity to investigate measurement accuracy in concentrated plumes where hundreds of species coexist. Here, we compare NO measurements by chemiluminescence (CL) and laser-induced fluorescence (LIF); NO2 measurements by CL, LIF, and cavity-enhanced spectroscopy (CES); HONO measurements by CES and iodide-adduct chemical ionization mass spectrometry (CIMS); and CO measurements by tunable diode laser absorption spectrometry (TDLAS) and integrated cavity output spectroscopy (ICOS). Additionally, total NOy measurements using the CL instrument were compared withΣNOy (= NO + NO2 + HONO + nitric acid (HNO3) + acyl peroxy nitrates (APNs) + submicrometer particulate nitrate (pNO3)). Other NOy species were not included in ΣNOy as they either contributed minimally to it (e.g., C1–C5 alkyl nitrates, nitryl chloride (ClNO2), dinitrogen pentoxide (N2O5)) or were not measured during FIREX-AQ (e.g., higher oxidized alkyl nitrates, nitrate (NO3), non-acyl peroxynitrates, coarse-mode aerosol nitrate). The aircraft instrument intercomparisons demonstrate the following points: (1) NO measurements by CL and LIF agreed well within instrument uncertainties but with potentially reduced time response for the CL instrument; (2) NO2 measurements by LIF and CES agreed well within instrument uncertainties, but CL NO2 was on average 10 % higher; (3) CES and CIMS HONO measurements were highly correlated in each fire plume transect, but the correlation slope of CES vs. CIMS for all 1 Hz data during FIREX-AQ was 1.8, which we attribute to a reduction in the CIMS sensitivity to HONO in high-temperature environments; (4) NOy budget closure was demonstrated for all flights within the combined instrument uncertainties of 25 %. However, we used a fluid dynamic flow model to estimate that average pNO3 sampling fraction through the NOy inlet in smoke was variable from one flight to another and ranged between 0.36 and 0.99, meaning that approximately 0 %–24 % on average of the total measured NOy in smoke may have been unaccounted for and may be due to unmeasured species such as organic nitrates; (5) CO measurements by ICOS and TDLAS agreed well within combined instrument uncertainties, but with a systematic offset that averaged 2.87 ppbv; and (6) integrating smoke plumes followed by fitting the integrated values of each plume improved the correlation between independent measurements.
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