The evolution of the Milky Way disk, which contains most of the stars in the Galaxy, is affected by several phenomena. For example, the bar and the spiral arms of the Milky Way induce radial ...migration of stars
and can trap or scatter stars close to orbital resonances
. External perturbations from satellite galaxies can also have a role, causing dynamical heating of the Galaxy
, ring-like structures in the disk
and correlations between different components of the stellar velocity
. These perturbations can also cause 'phase wrapping' signatures in the disk
, such as arched velocity structures in the motions of stars in the Galactic plane. Some manifestations of these dynamical processes have already been detected, including kinematic substructure in samples of nearby stars
, density asymmetries and velocities across the Galactic disk that differ from the axisymmetric and equilibrium expectations
, especially in the vertical direction
, and signatures of incomplete phase mixing in the disk
. Here we report an analysis of the motions of six million stars in the Milky Way disk. We show that the phase-space distribution contains different substructures with various morphologies, such as snail shells and ridges, when spatial and velocity coordinates are combined. We infer that the disk must have been perturbed between 300 million and 900 million years ago, consistent with estimates of the previous pericentric passage of the Sagittarius dwarf galaxy. Our findings show that the Galactic disk is dynamically young and that modelling it as time-independent and axisymmetric is incorrect.
High-sensitivity assays can quantify cardiac troponins I and T (hs-cTnI, hs-cTnT) in individuals with no clinically manifest myocardial injury.
The goal of this study was to assess associations of ...cardiac troponin concentration with cardiovascular disease (CVD) outcomes in primary prevention studies.
A search was conducted of PubMed, Web of Science, and EMBASE for prospective studies published up to September 2016, reporting on associations of cardiac troponin concentration with first-ever CVD outcomes (i.e., coronary heart disease CHD, stroke, or the combination of both). Study-specific estimates, adjusted for conventional risk factors, were extracted by 2 independent reviewers, supplemented with de novo data from PROSPER (Pravastatin in Elderly Individuals at Risk of Vascular Disease Study), then pooled by using random effects meta-analysis.
A total of 28 relevant studies were identified involving 154,052 participants. Cardiac troponin was detectable in 80.0% (hs-cTnI: 82.6%; hs-cTnT: 69.7%). In PROSPER, positive associations of log-linear shape were observed between hs-cTnT and CVD outcomes. In the meta-analysis, the relative risks comparing the top versus the bottom troponin third were 1.43 (95% confidence interval CI: 1.31 to 1.56) for CVD (11,763 events), 1.67 (95% CI: 1.50 to 1.86) for fatal CVD (7,775 events), 1.59 (95% CI: 1.38 to 1.83) for CHD (7,061 events), and 1.35 (95% CI: 1.23 to 1.48) for stroke (2,526 events). For fatal CVD, associations were stronger in North American studies (p = 0.010) and those measuring hs-cTnT rather than hs-cTnI (p = 0.027).
In the general population, high cardiac troponin concentration within the normal range is associated with increased CVD risk. This association is independent of conventional risk factors, strongest for fatal CVD, and applies to both CHD and stroke.
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The Earth’s thermosphere and ionosphere constitute a dynamic system that varies daily in response to energy inputs from above and from below. This system can exhibit a significant response within an ...hour to changes in those inputs, as plasma and fluid processes compete to control its temperature, composition, and structure. Within this system, short wavelength solar radiation and charged particles from the magnetosphere deposit energy, and waves propagating from the lower atmosphere dissipate.
Understanding the global-scale response of the thermosphere-ionosphere
(
T-I
)
system to these drivers is essential to advancing our physical understanding of coupling between the space environment and the Earth’s atmosphere
. Previous missions have successfully determined how the “climate” of the T-I system responds. The Global-scale Observations of the Limb and Disk (GOLD) mission will determine how the “weather” of the T-I responds, taking the next step in understanding the coupling between the space environment and the Earth’s atmosphere. Operating in geostationary orbit, the GOLD imaging spectrograph will measure the Earth’s emissions from 132 to 162 nm. These measurements will be used image two critical variables—thermospheric temperature and composition, near 160 km—on the dayside disk at half-hour time scales. At night they will be used to image the evolution of the low latitude ionosphere in the same regions that were observed earlier during the day. Due to the geostationary orbit being used the mission observes the same hemisphere repeatedly, allowing the unambiguous separation of spatial and temporal variability over the Americas.
People's differences in cognitive functions are partly heritable and are associated with important life outcomes. Previous genome-wide association (GWA) studies of cognitive functions have found ...evidence for polygenic effects yet, to date, there are few replicated genetic associations. Here we use data from the UK Biobank sample to investigate the genetic contributions to variation in tests of three cognitive functions and in educational attainment. GWA analyses were performed for verbal-numerical reasoning (N=36 035), memory (N=112 067), reaction time (N=111 483) and for the attainment of a college or a university degree (N=111 114). We report genome-wide significant single-nucleotide polymorphism (SNP)-based associations in 20 genomic regions, and significant gene-based findings in 46 regions. These include findings in the ATXN2, CYP2DG, APBA1 and CADM2 genes. We report replication of these hits in published GWA studies of cognitive function, educational attainment and childhood intelligence. There is also replication, in UK Biobank, of SNP hits reported previously in GWA studies of educational attainment and cognitive function. GCTA-GREML analyses, using common SNPs (minor allele frequency>0.01), indicated significant SNP-based heritabilities of 31% (s.e.m.=1.8%) for verbal-numerical reasoning, 5% (s.e.m.=0.6%) for memory, 11% (s.e.m.=0.6%) for reaction time and 21% (s.e.m.=0.6%) for educational attainment. Polygenic score analyses indicate that up to 5% of the variance in cognitive test scores can be predicted in an independent cohort. The genomic regions identified include several novel loci, some of which have been associated with intracranial volume, neurodegeneration, Alzheimer's disease and schizophrenia.
The Galactic warp revealed by Gaia DR2 kinematics Poggio, E; Drimmel, R; Lattanzi, M G ...
Monthly notices of the Royal Astronomical Society. Letters,
11/2018, Letnik:
481, Številka:
1
Journal Article
Recenzirano
Odprti dostop
ABSTRACT Using Gaia DR2 astrometry, we map the kinematic signature of the Galactic stellar warp out to a distance of 7 kpc from the Sun. Combining Gaia DR2 and 2-Micron All Sky Survey photometry, we ...identify, via a probabilistic approach, $599 \, 494$ upper main sequence (UMS) stars and $12\, 616\, 068$ giants without the need for individual extinction estimates. The spatial distribution of the UMS stars clearly shows segments of the nearest spiral arms. The large-scale kinematics of both the UMS and giant populations show a clear signature of the warp of the Milky Way, apparent as a gradient of 5–6 km s−1 in the vertical velocities from 8 to 14 kpc in Galactic radius. The presence of the signal in both samples, which have different typical ages, suggests that the warp is a gravitationally induced phenomenon.
ABSTRACT
We report on precise Doppler measurements of L231-32 (TOI-270), a nearby M dwarf (d = 22 pc, M⋆ = 0.39 M⊙, R⋆ = 0.38 R⊙), which hosts three transiting planets that were recently discovered ...using data from the Transiting Exoplanet Survey Satellite (TESS). The three planets are 1.2, 2.4, and 2.1 times the size of Earth and have orbital periods of 3.4, 5.7, and 11.4 d. We obtained 29 high-resolution optical spectra with the newly commissioned Echelle Spectrograph for Rocky Exoplanet and Stable Spectroscopic Observations (ESPRESSO) and 58 spectra using the High Accuracy Radial velocity Planet Searcher (HARPS). From these observations, we find the masses of the planets to be 1.58 ± 0.26, 6.15 ± 0.37, and 4.78 ± 0.43 M⊕, respectively. The combination of radius and mass measurements suggests that the innermost planet has a rocky composition similar to that of Earth, while the outer two planets have lower densities. Thus, the inner planet and the outer planets are on opposite sides of the ‘radius valley’ – a region in the radius-period diagram with relatively few members – which has been interpreted as a consequence of atmospheric photoevaporation. We place these findings into the context of other small close-in planets orbiting M dwarf stars, and use support vector machines to determine the location and slope of the M dwarf (Teff < 4000 K) radius valley as a function of orbital period. We compare the location of the M dwarf radius valley to the radius valley observed for FGK stars, and find that its location is a good match to photoevaporation and core-powered mass-loss models. Finally, we show that planets below the M dwarf radius valley have compositions consistent with stripped rocky cores, whereas most planets above have a lower density consistent with the presence of a H-He atmosphere.
Like commercial marketing, social marketing uses the 4 “Ps” and seeks exchange of value between the marketer and consumer. Behaviors such as handwashing, and products such as those for oral ...rehydration treatment (ORT), can be marketed like commercial products in developing countries. Although social marketing in these areas is growing, there has been no systematic review of the current state of practice, research and evaluation.
We searched the literature for published peer-reviewed studies available through major online publication databases. We identified manuscripts in the health, social science, and business literature on social marketing that used at least one of the 4 Ps of marketing and had a behavioral objective targeting the behaviors or products related to improving water and sanitation. We developed formalized decision rules and applied them in identifying articles for review. We initially identified 117 articles and reviewed a final set of 32 that met our criteria.
Social marketing is a widespread strategy. Marketing efforts have created high levels of awareness of health threats and solutions, including behavior change and socially marketed products. There is widespread use of the 4 Ps of marketing, with price interventions being the least common. Evaluations show consistent improvements in behavioral mediators but mixed results in behavior change.
Interventions have successfully used social marketing following widely recommended strategies. Future evaluations need to focus on mediators that explain successful behavior change in order to identify best practices and improve future programs. More rigorous evaluations including quasi-experimental designs and randomized trials are needed. More consistent reporting of evaluation results that permits meta-analysis of effects is needed.
•Water and sanitation behaviors can be marketed like commercial products.•There has been no systematic review of theory, research, and practice in this area.•We identified 32 articles over a 22 year period that met search criteria.•Evaluations show improvements in mediators but mixed results in behavior change.•Social marketing can improve water and sanitation programs worldwide.
A suite of grounding-line landforms on the Antarctic seafloor, imaged at submeter horizontal resolution from an autonomous underwater vehicle, enables calculation of ice sheet retreat rates from a ...complex of grounding-zone wedges on the Larsen continental shelf, western Weddell Sea. The landforms are delicate sets of up to 90 ridges, <1.5 meters high and spaced 20 to 25 meters apart. We interpret these ridges as the product of squeezing up of soft sediment during the rise and fall of the retreating ice sheet grounding line during successive tidal cycles. Grounding-line retreat rates of 40 to 50 meters per day (>10 kilometers per year) are inferred during regional deglaciation of the Larsen shelf. If repeated today, such rapid mass loss to the ocean would have clear implications for increasing the rate of global sea level rise.
Mutations in the gene encoding the bone morphogenetic protein receptor type II (BMPR2) are the commonest genetic cause of pulmonary arterial hypertension (PAH). However, the effect of BMPR2 mutations ...on clinical phenotype and outcomes remains uncertain.
We analysed individual participant data of 1550 patients with idiopathic, heritable, and anorexigen-associated PAH from eight cohorts that had been systematically tested for BMPR2 mutations. The primary outcome was the composite of death or lung transplantation. All-cause mortality was the secondary outcome. Hazard ratios (HRs) for death or transplantation and all-cause mortality associated with the presence of BMPR2 mutation were calculated using Cox proportional hazards models stratified by cohort.
Overall, 448 (29%) of 1550 patients had a BMPR2 mutation. Mutation carriers were younger at diagnosis (mean age 35·4 SD 14·8 vs 42·0 17·8 years), had a higher mean pulmonary artery pressure (60·5 13·8 vs 56·4 15·3 mm Hg) and pulmonary vascular resistance (16·6 8·3 vs 12·9 8·3 Wood units), and lower cardiac index (2·11 0·69 vs 2·51 0·92 L/min per m2; all p<0·0001). Patients with BMPR2 mutations were less likely to respond to acute vasodilator testing (3% 10 of 380 vs 16% 147 of 907; p<0·0001). Among the 1164 individuals with available survival data, age-adjusted and sex-adjusted HRs comparing BMPR2 mutation carriers with non-carriers were 1·42 (95% CI 1·15–1·75; p=0·0011) for the composite of death or lung transplantation and 1·27 (1·00–1·60; p=0·046) for all-cause mortality. These HRs were attenuated after adjustment for potential mediators including pulmonary vascular resistance, cardiac index, and vasoreactivity. HRs for death or transplantation and all-cause mortality associated with BMPR2 mutation were similar in men and women, but higher in patients with a younger age at diagnosis (p=0·0030 for death or transplantation, p=0·011 for all-cause mortality).
Patients with PAH and BMPR2 mutations present at a younger age with more severe disease, and are at increased risk of death, and death or transplantation, compared with those without BMPR2 mutations.
Cambridge NIHR Biomedical Research Centre, Medical Research Council, British Heart Foundation, Assistance Publique-Hôpitaux de Paris, INSERM, Université Paris-Sud, Intermountain Research and Medical Foundation, Vanderbilt University, National Center for Advancing Translational Sciences, National Institutes of Health, National Natural Science Foundation of China, and Beijing Natural Science Foundation.
Despite the wealth of evidence regarding effective health behavior change techniques using digital interventions to focus on residents of high-income countries, there is limited information of a ...similar nature for low- and middle-income countries.
The aim of this review is to identify and describe the available literature on effective social media-based behavior change interventions within low- and middle-income countries.
This systematic review was conducted in accordance with the 2009 PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) guidelines. We searched PubMed, Embase, Elsevier, CINAHL, PsycInfo, and Global Index Medicus, and the final search was conducted on April 6, 2021. We excluded studies published before 2000 because of the subject matter. We included studies that evaluated interventions conducted at least partly on a social media platform.
We identified 1832 studies, of which 108 (5.89%) passed title-abstract review and were evaluated by full-text review. In all, 30.6% (33/108) were included in the final analysis. Although 22 studies concluded that the social media intervention was effective, only 13 quantified the level of social media engagement, of which, few used theory (n=8) or a conceptual model (n=5) of behavior change.
We identified gaps in the settings of interventions, types and sectors of interventions, length of follow-up, evaluation techniques, use of theoretical and conceptual models, and discussions of the privacy implications of social media use.
PROSPERO CRD42020223572; https://www.crd.york.ac.uk/prospero/display_record.php?RecordID=223572.
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