To assess the potential benefit of digital health interventions (DHIs) on cardiovascular disease (CVD) outcomes (CVD events, all-cause mortality, hospitalizations) and risk factors compared with ...non-DHIs.
We conducted a systematic search of PubMed, MEDLINE, EMBASE, Web of Science, Ovid, CINHAL, ERIC, PsychINFO, Cochrane, and Cochrane Central Register of Controlled Trials for articles published from January 1, 1990, through January 21, 2014. Included studies examined any element of DHI (telemedicine, Web-based strategies, e-mail, mobile phones, mobile applications, text messaging, and monitoring sensors) and CVD outcomes or risk factors. Two reviewers independently evaluated study quality utilizing a modified version of the Cochrane Collaboration risk assessment tool. Authors extracted CVD outcomes and risk factors for CVD such as weight, body mass index, blood pressure, and lipid levels from 51 full-text articles that met validity and inclusion criteria.
Digital health interventions significantly reduced CVD outcomes (relative risk, 0.61; 95% CI, 0.46-0.80; P<.001; I(2)=22%). Concomitant reductions in weight (-2.77 lb 95% CI, -4.49 to -1.05 lb; P<.002; I(2)=97%) and body mass index (-0.17 kg/m(2) 95% CI, -0.32 kg/m(2) to -0.01 kg/m(2); P=.03; I(2)=97%) but not blood pressure (-1.18 mm Hg 95% CI, -2.93 mm Hg to 0.57 mm Hg; P=.19; I(2)=100%) were found in these DHI trials compared with usual care. In the 6 studies reporting Framingham risk score, 10-year risk percentages were also significantly improved (-1.24%; 95% CI, -1.73% to -0.76%; P<.001; I(2)=94%). Results were limited by heterogeneity not fully explained by study population (primary or secondary prevention) or DHI modality.
Overall, these aggregations of data provide evidence that DHIs can reduce CVD outcomes and have a positive impact on risk factors for CVD.
ABSTRACT We present a comprehensive analysis of the structural properties and luminosities of the 23 dwarf spheroidal galaxies that fall within the footprint of the Pan-Andromeda Archaeological ...Survey (PAndAS). These dwarf galaxies represent the large majority of Andromeda's known satellite dwarf galaxies and cover a wide range in luminosity ( or ) and surface brightness ( mag arcsec−2). We confirm most previous measurements, but we find And XIX to be significantly larger than before ( , ) and cannot derive parameters for And XXVII as it is likely not a bound stellar system. We also significantly revise downward the luminosities of And XV and And XVI, which are now or . Finally, we provide the first detailed analysis of Cas II/And XXX, a fairly faint system ( ) of typical size ( ), located in close proximity to the two bright elliptical dwarf galaxies NGC 147 and NGC 185. Combined with the set of homogeneous distances published in an earlier contribution, our analysis dutifully tracks all relevant sources of uncertainty in the determination of the properties of the dwarf galaxies from the PAndAS photometric catalog. We further publish the posterior probability distribution functions of all the parameters we fit for in the form of MCMC chains available online; these inputs should be used in any analysis that aims to remain truthful to the data and properly account for covariance between parameters.
Dwarf satellite galaxies are thought to be the remnants of the population of primordial structures that coalesced to form giant galaxies like the Milky Way. It has previously been suspected that ...dwarf galaxies may not be isotropically distributed around our Galaxy, because several are correlated with streams of H I emission, and may form coplanar groups. These suspicions are supported by recent analyses. It has been claimed that the apparently planar distribution of satellites is not predicted within standard cosmology, and cannot simply represent a memory of past coherent accretion. However, other studies dispute this conclusion. Here we report the existence of a planar subgroup of satellites in the Andromeda galaxy (M 31), comprising about half of the population. The structure is at least 400 kiloparsecs in diameter, but also extremely thin, with a perpendicular scatter of less than 14.1 kiloparsecs. Radial velocity measurements reveal that the satellites in this structure have the same sense of rotation about their host. This shows conclusively that substantial numbers of dwarf satellite galaxies share the same dynamical orbital properties and direction of angular momentum. Intriguingly, the plane we identify is approximately aligned with the pole of the Milky Way's disk and with the vector between the Milky Way and Andromeda.
Celotno besedilo
Dostopno za:
DOBA, IJS, IZUM, KILJ, KISLJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
ABSTRACT
With a central surface brightness of μ0 = 29.3 mag arcsec−2, and half-light radius of $r_{\rm half}=3.1^{+0.9}_{-1.1}$ kpc, Andromeda XIX (And XIX) is an extremely diffuse satellite of ...Andromeda. We present spectra for ∼100 red giant branch stars in this galaxy, plus 16 stars in a nearby stellar stream. With this exquisite data set, we re-derive the properties of And XIX, measuring a systemic velocity of 〈vr〉 = −109.0 ± 1.6 km s−1 and a velocity dispersion of $\sigma _{vr} = 7.8^{+1.7}_{-1.5}$ km s−1 (higher than derived in our previous work). We marginally detect a velocity gradient along the major axis of $\frac{{\rm d} v}{{\rm d}\chi }= -2.1\pm 1.8~{\rm km\, s}^{-1}$ kpc−1. We find its mass-to-light ratio is higher than galaxies of comparable stellar mass (M/L_{\rm half} = 278^{+146}_{-198}\, \mathrm{M}_\odot /\mathrm{L}_\odot$), but its dynamics place it in a halo with a similar total mass to these galaxies. This could suggest that And XIX is a ‘puffed up’ dwarf galaxy, whose properties have been altered by tidal processes, similar to its Milky Way counterpart, Antlia II. For the nearby stream, we measure $v_r=-279.2\pm 3.7~{\rm km\, s}^{-1}$, and $\sigma _v=13.8^{+3.5}_{-2.6}~{\rm km\, s}^{-1}$. We measure its metallicity, and find it to be more metal rich than And XIX, implying that the two features are unrelated. Finally, And XIX’s dynamical and structural properties imply it is a local analogue to ultradiffuse galaxies (UDGs). Its complex dynamics suggest that the masses of distant UDGs measured from velocity dispersions alone should be carefully interpreted.
ABSTRACT We present a study of the recently discovered compact stellar system Triangulum II. From observations conducted with the DEIMOS spectrograph on Keck II, we obtained spectra for 13 member ...stars that follow the CMD features of this very faint stellar system and include two bright red giant branch stars. Tri II has a very negative radial velocity ( ) that translates to and confirms it is a Milky Way satellite. We show that, despite the small data set, there is evidence that Tri II has complex internal kinematics. Its radial velocity dispersion increases from in the central to outwards. The velocity dispersion of the full sample is inferred to be . From the two bright RGB member stars we measure an average metallicity , placing Tri II among the most metal-poor Milky Way dwarf galaxies. In addition, the spectra of the fainter member stars exhibit differences in their line widths that could be the indication of a metallicity dispersion in the system. All these properties paint a complex picture for Tri II, whose nature and current state are largely speculative. The inferred metallicity properties of the system however lead us to favor a scenario in which Tri II is a dwarf galaxy that is either disrupting or embedded in a stellar stream.
Cnidaria, the sister group to Bilateria, is a highly diverse group of animals in terms of morphology, lifecycles, ecology, and development. How this diversity originated and evolved is not well ...understood because phylogenetic relationships among major cnidarian lineages are unclear, and recent studies present contrasting phylogenetic hypotheses. Here, we use transcriptome data from 15 newly-sequenced species in combination with 26 publicly available genomes and transcriptomes to assess phylogenetic relationships among major cnidarian lineages. Phylogenetic analyses using different partition schemes and models of molecular evolution, as well as topology tests for alternative phylogenetic relationships, support the monophyly of Medusozoa, Anthozoa, Octocorallia, Hydrozoa, and a clade consisting of Staurozoa, Cubozoa, and Scyphozoa. Support for the monophyly of Hexacorallia is weak due to the equivocal position of Ceriantharia. Taken together, these results further resolve deep cnidarian relationships, largely support traditional phylogenetic views on relationships, and provide a historical framework for studying the evolutionary processes involved in one of the most ancient animal radiations.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
KEY MESSAGE : A switchgrass protoplast system was developed, achieving a cost reduction of ~1000-fold, a threefold increase in transformation efficiency, and a fourfold reduction in required DNA ...quantity compared to previous methods. In recent years, there has been a resurgence in the use of protoplast systems for rapid screening of gene silencing and genome-editing targets for siRNA, miRNA, and CRISPR technologies. In the case of switchgrass (Panicum virgatum L.), to achieve economic feasibility for biofuel production, it is necessary to develop plants with decreased cell wall recalcitrance to reduce processing costs. To achieve this goal, transgenic plants have been generated with altered cell wall chemistry; however, with limited success owing to the complexity of cell walls. Because of the considerable cost, time, and effort required to screen transgenic plants, a protoplast system that can provide data at an early stage has potential to eliminate low performing candidate genes/targets prior to the creation of transgenic plants. Despite the advantages of protoplast systems, protoplast isolation in switchgrass has proven costly, requiring expensive lab-grade enzymes and high DNA quantities. In this paper, we describe a low-cost protoplast isolation system using a mesophyll culture approach and a cell suspension culture. Results from this work show a cost reduction of ~1000-fold compared to previous methods of protoplast isolation in switchgrass, with a cost of $0.003 (USD) per reaction for mesophyll protoplasts and $0.018 for axenic cell culture-derived protoplasts. Further, the efficiency of protoplast transformation was optimized threefold over previous methods, despite a fourfold reduction in DNA quantity. The methods developed in this work remove the cost barrier previously limiting high-throughput screening of genome-editing and gene silencing targets in switchgrass, paving the way for more efficient development of transgenic plants.
ABSTRACT
Andromeda XXI (And XXI) has been proposed as a dwarf spheroidal galaxy with a central dark matter density that is lower than expected in the standard $\Lambda$ cold dark matter ...($\Lambda$CDM) cosmology. In this work, we present dynamical observations for 77 member stars in this system, more than doubling previous studies to determine whether this galaxy is truly a low-density outlier. We measure a systemic velocity of $v_r=-363.4\pm 1.0{\rm \, km\, s^{-1}}$ and a velocity dispersion of $\sigma _v=6.1^{+1.0}_{-0.9}{\rm \, km\, s^{-1}}$, consistent with previous work and within $1\sigma$ of predictions made using the modified Newtonian dynamics framework. We also measure the metallicity of our member stars from their spectra, finding a mean value of ${\rm Fe/H}=-1.7\pm 0.1$ dex. We model the dark matter density profile of And XXI using an improved version of gravsphere, finding a central density of $\rho _{\rm DM}({\rm 150 pc})=2.6_{-1.5}^{+2.4} \times 10^7 \, {\rm M_\odot \, kpc^{-3}}$ at 68 per cent confidence, and a density at two half-light radii of $\rho _{\rm DM}({\rm 1.75 kpc})=0.9_{-0.2}^{+0.3} \times 10^6 \, {\rm M_\odot \, kpc^{-3}}$ at 68 per cent confidence. These are both a factor of${\sim }3\!-\!5$ lower than the densities expected from abundance matching in $\Lambda$CDM. We show that this cannot be explained by ‘dark matter heating’ since And XXI had too little star formation to significantly lower its inner dark matter density, while dark matter heating only acts on the profile inside the half-light radius. However, And XXI’s low density can be accommodated within $\Lambda$CDM if it experienced extreme tidal stripping (losing ${\gt}95{{\ \rm per\ cent}}$ of its mass), or if it inhabits a low-concentration halo on a plunging orbit that experienced repeated tidal shocks.
We present a homogeneous kinematic analysis of red giant branch stars within 18 of the 28 Andromeda dwarf spheroidal (dSph) galaxies, obtained using the Keck I/LRIS and Keck II/DEIMOS spectrographs. ...Based on their g - i colors (taken with the CFHT/MegaCam imager), physical positions on the sky, and radial velocities, we assign probabilities of dSph membership to each observed star. Using this information, the velocity dispersions, central masses, and central densities of the dark matter halos are calculated for these objects, and compared with the properties of the Milky Way dSph population. We also measure the average metallicity (Fe/H) from the co-added spectra of member stars for each M31 dSph and find that they are consistent with the trend of decreasing Fe/H with luminosity observed in the Milky Way population. We find that three of our studied M31 dSphs appear as significant outliers in terms of their central velocity dispersion, And XIX, XXI, and XXV, all of which have large half-light radii (> ~700 pc) and low velocity dispersions (sigma sub(nu) < 5 km s super(-1)). In addition, And XXV has a mass-to-light ratio within its half-light radius of just (ProQuest: Formulae and/or non-USASCII text omitted), making it consistent with a simple stellar system with no appreciable dark matter component within its 1sigma uncertainties. We suggest that the structure of the dark matter halos of these outliers have been significantly altered by tides.
We investigate the claim that all dwarf spheroidal galaxies (dSphs) reside within halos that share a common, universal mass profile as has been derived for dSphs of the galaxy. By folding in ...kinematic information for 25 Andromeda dSphs, more than doubling the previous sample size, we find that a singular mass profile cannot be found to fit all of the observations well. Further, the best-fit dark matter density profile measured solely for the Milky Way dSphs is marginally discrepant with that of the Andromeda dSphs (at just beyond the 1sigma level), where a profile with lower maximum circular velocity, and hence mass, is preferred. The agreement is significantly better when three extreme Andromeda outliers, And XIX, XXI, and XXV, all of which have large half-light radii (gap600 pc) and low-velocity dispersions (sigma sub(upsilon) < 5 km s super(-1)), are omitted from the sample. We argue that the unusual properties of these outliers are likely caused by tidal interactions with the host galaxy.
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