We present the results of a blind exercise to test the recoverability of stellar rotation and differential rotation in Kepler light curves. The simulated light curves lasted 1000 d and included ...activity cycles, Sun-like butterfly patterns, differential rotation and spot evolution. The range of rotation periods, activity levels and spot lifetime were chosen to be representative of the Kepler data of solar-like stars. Of the 1000 simulated light curves, 770 were injected into actual quiescent Kepler light curves to simulate Kepler noise. The test also included five 1000-d segments of the Sun's total irradiance variations at different points in the Sun's activity cycle. Five teams took part in the blind exercise, plus two teams who participated after the content of the light curves had been released. The methods used included Lomb–Scargle periodograms and variants thereof, autocorrelation function and wavelet-based analyses, plus spot modelling to search for differential rotation. The results show that the ‘overall’ period is well recovered for stars exhibiting low and moderate activity levels. Most teams reported values within 10 per cent of the true value in 70 per cent of the cases. There was, however, little correlation between the reported and simulated values of the differential rotation shear, suggesting that differential rotation studies based on full-disc light curves alone need to be treated with caution, at least for solar-type stars. The simulated light curves and associated parameters are available online for the community to test their own methods.
The vast majority of published papers concerning seagrass meadows contain statements to the effect that seagrass beds serve as important nurseries for many species. We reviewed more than 200 papers ...that were relevant to the nursery role hypothesis. We used both vote counting and meta-analytic techniques to evaluate whether the body of previous studies that report seagrass meadows to be nursery grounds actually contain data that support this proposition. We restricted our analyses to papers that compared seagrass beds to other habitats, and examined data on a variety of well-studied species concerning their density, growth, survival and migration to adult habitat. Within this group of papers, we considered potential factors that could influence the nursery function (e.g. location, or laboratory vs field studies). We also evaluated case histories of well-documented large-scale seagrass losses on the nursery function. Major results were consistent with the expectations that abundance, growth and survival were greater in seagrass than in unstructured habitats. Abundance data also suggested that seagrass beds in the Northern Hemisphere might be more important as nursery areas than those in the Southern Hemisphere. Surprisingly, few significant differences existed in abundance, growth or survival when seagrass meadows were compared to other structured habitats, such as oyster or cobble reefs, or macroalgal beds. Nor were there decreases in harvests of commercially important species that could clearly be attributed to significant seagrass declines in 3 well-studied areas. However, there were decreased abundances of juveniles of commercially important species in these areas, suggesting a strong link between seagrass abundance and those of juvenile finfish and shellfish. One important implication of these results is that structure per se, rather than the type of structure, appears to be an important determinant of nursery value. Clearly, more rigorous studies that test all aspects of the nursery role hypothesis are clearly needed for seagrass meadows as well as other structured habitats. The results of such studies will allow better decisions to be made concerning the conservation and restoration of marine habitats.
To investigate the origin of the features discovered in the exoplanet population, the knowledge of exoplanets' mass and radius with a good precision (≲10%) is essential. To achieve this purpose the ...discovery of transiting exoplanets around bright stars is of prime interest. In this paper, we report the discovery of three transiting exoplanets by the SuperWASP survey and the SOPHIE spectrograph with mass and radius determined with a precision better than 15%. WASP-151b and WASP-153b are two hot Saturns with masses, radii, densities and equilibrium temperatures of 0.31−0.03+0.04 MJ$0.31_{-0.03}^{+0.04}\,{M_{\textrm{J}}}$0.31−0.03+0.04 MJ, 1.13−0.03+0.03 RJ$1.13_{-0.03}^{+0.03}\,{R_{\textrm{J}}}$1.13−0.03+0.03 RJ, 0.22−0.02+0.03 ρJ$0.22_{-0.02}^{+0.03}\,\rho_{\mathrm{J}}$0.22−0.02+0.03 ρJ and 1290−10+20 K$1290_{-10}^{+20}~\mathrm{K}$1290−10+20 K, and 0.39−0.02+0.02 MJ$0.39_{-0.02}^{+0.02}\,{M_{\textrm{J}}}$0.39−0.02+0.02 MJ, 1.55−0.08+0.10 RJ$1.55_{-0.08}^{+0.10}\,{R_{\textrm{J}}}$1.55−0.08+0.10 RJ, 0.11−0.02+0.02 ρJ$0.11_{-0.02}^{+0.02}\,\rho_{\mathrm{J}}$0.11−0.02+0.02 ρJ and 1700−0.40+0.40 K$1700_{-40}^{+40}~\mathrm{K}$1700−40+40 K, respectively. Their host stars are early G type stars (with mag V ~ 13) and their orbital periods are 4.53 and 3.33 days, respectively. WASP-156b is a super-Neptune orbiting a K type star (mag V = 11.6). It has a mass of $0.128_{-0.009}^{+0.010}\,{M_{\rm J}}$0.128−0.009+0.010 MJ0.128-0.009+0.010MJ, a radius of $0.51_{-0.02}^{+0.02}\,{R_{\rm J}}$0.51−0.02+0.02 RJ0.51-0.02+0.02RJ, a density of 1.0−0.1+0.1 ρJ$1.0_{-0.1}^{+0.1}\,\rho_{\mathrm{J}}$1.0−0.1+0.1 ρJ, an equilibrium temperature of 970−20+30 K$970_{-20}^{+30}~\mathrm{K}$970−20+30 K and an orbital period of 3.83 days. The radius of WASP-151b appears to be only slightly inflated, while WASP-153b presents a significant radius anomaly compared to a recently published model. WASP-156b, being one of the few well characterized super-Neptunes, will help to constrain the still debated formation of Neptune size planets and the transition between gas and ice giants. The estimates of the age of these three stars confirms an already observed tendency for some stars to have gyrochronological ages significantly lower than their isochronal ages. We propose that high eccentricity migration could partially explain this behavior for stars hosting a short period planet. Finally, these three planets also lie close to (WASP-151b and WASP-153b) or below (WASP-156b) the upper boundary of the Neptunian desert. Their characteristics support that the ultra-violet irradiation plays an important role in this depletion of planets observed in the exoplanet population.
RW Aur is a young binary star that experienced a deep dimming in 2010-2011 in component A and a second even deeper dimming from summer 2014 to summer 2016. We present new unresolved multiband ...photometry during the 2014-2016 eclipse, new emission line spectroscopy before and during the dimming, archive infrared photometry between 2014 and 2015, as well as an overview of literature data. Spectral observations were carried out with the Fibre-fed RObotic Dual-beam Optical Spectrograph on the Liverpool Telescope. Photometric monitoring was done with the Las Cumbres Observatory Global Telescope Network and James Gregory Telescope. Our photometry shows that RW Aur dropped in brightness to R = 12.5 in 2016 March. In addition to the long-term dimming trend, RW Aur is variable on time-scales as short as hours. The short-term variation is most likely due to an unstable accretion flow. This, combined with the presence of accretion-related emission lines in the spectra suggest that accretion flows in the binary system are at least partially visible during the eclipse. The equivalent width of Oi increases by a factor of 10 in 2014, coinciding with the dimming event, confirming previous reports. The blueshifted part of the H... profile is suppressed during the eclipse. In combination with the increase in mid-infrared brightness during the eclipse reported in the literature and seen in WISE archival data, and constraints on the geometry of the disc around RW Aur A we arrive at the conclusion that the obscuring screen is part of a wind emanating from the inner disc. (ProQuest: ... denotes formulae/symbols omitted.)
The global burden of psoriatic skin disease Goff, K.L.; Karimkhani, C.; Boyers, L.N. ...
British journal of dermatology (1951),
June 2015, Letnik:
172, Številka:
6
Journal Article
Adipose tissue is an attractive source of mesenchymal stem cells (MSC) as it is largely dispensable and readily accessible through minimally invasive procedures such as liposuction. Until recently ...MSC could only be isolated in a process involving ex-vivo culture and their in-vivo identity, location and frequency remained elusive. We have documented that pericytes (CD45-, CD146+, and CD34-) and adventitial cells (CD45-, CD146-, CD34+) (collectively termed perivascular stem cells or PSC) represent native ancestors of the MSC, and can be prospectively purified using fluorescence activated cell sorting (FACS). In this study we describe an optimized protocol that aims to deliver pure, viable and consistent yields of PSC from adipose tissue. We analysed the frequency of PSC within adipose tissue, and the effect of patient and procedure based variables on this yield.
Within this twin centre study we analysed the adipose tissue of n = 131 donors using flow cytometry to determine the frequency of PSC and correlate this with demographic and processing data such as age, sex, BMI and cold storage time of the tissue.
The mean number of stromal vascular fraction (SVF) cells from 100 ml of lipoaspirate was 34.4 million. Within the SVF, mean cell viability was 83 %, with 31.6 % of cells being haematopoietic (CD45+). Adventitial cells and pericytes represented 33.0 % and 8 % of SVF cells respectively. Therefore, a 200 ml lipoaspirate would theoretically yield 23.2 million viable prospectively purified PSC - sufficient for many reconstructive and regenerative applications. Minimal changes were observed in respect to age, sex and BMI suggesting universal potential application.
Adipose tissue contains two anatomically and phenotypically discreet populations of MSC precursors - adventitial cells and pericytes - together referred to as perivascular stem cells (PSC). More than 9 million PSC per 100 ml of lipoaspirate can be rapidly purified to homogeneity using flow cytometry in clinically relevant numbers potentially circumventing the need for purification and expansion by culture prior to clinical use. The number and viability of PSC are minimally affected by patient age, sex, BMI or the storage time of the tissue, but the quality and consistency of yield can be significantly influenced by procedure based variables.
This study proposes an accurate method in assessing chronological age of the adolescents using a machine learning approach using MRI images. We also examined the value of MRI with Tanner-Whitehouse 3 ...(TW3) method in assessing skeletal maturity. Seventy-nine 12–17-year-old healthy Hong Kong Chinese adolescents were recruited. The left hand and wrist region were scanned by a dedicated skeletal MRI scanner. T1-weighted three-dimensional coronal view images for the left hand and wrist region were acquired. Independent maturity indicators such as subject body height, body weight, bone marrow composition intensity quantified by MRI, and TW3 skeletal age were included for artificial neural network (ANN) analysis. Our results indicated that the skeletal age was generally underestimated using TW3 method, and significant difference (
p
< 0.05) was noted for skeletal age with chronological age for female category and at later stage of adolescence (15 to 17 years old) in both genders. In our proposed machine learning approach, ages determined by ANN method agreed well with chronological age (
p
> 0.05).The machine learning approach using ANN method was about 10-fold more accurate than the TW3 method using MRI alone. It offers a more objective and accurate solution for prospective chronological maturity assessment for adolescents.
Aims. We present the discovery and characterisation of the exoplanets WASP-113b and WASP-114b by the WASP surveys, SOPHIE and CORALIE. Methods. The planetary nature of the systems was established by ...performing follow-up photometric and spectroscopic observations. The follow-up data were combined with the WASP-photometry and analysed with an MCMC code to obtain system parameters. Results. The host stars WASP-113 and WASP-114 are very similar. They are both early G-type stars with an effective temperature of ~5900 K, Fe/H ~ 0.12, and log g~ 4.1 dex. However, WASP-113 is older than WASP-114. Although the planetary companions have similar radii, WASP-114b is almost four times heavier than WASP-113b. WASP-113b has a mass of 0.48 MJup and an orbital period of ~4.5 days; WASP-114b has a mass of 1.77 MJup and an orbital period of ~1.5 days. Both planets have inflated radii, in particular WASP-113 with a radius anomaly of ℜ = 0.35. The high scale height of WASP-113b (~950 km) makes it a good target for follow-up atmospheric observations.
We present the discovery of three new transiting giant planets, first detected with the WASP telescopes, and establish their planetary nature with follow up spectroscopy and ground-based photometric ...light curves. WASP-92 is an F7 star, with a moderately inflated planet orbiting with a period of 2.17 d, which has R sub( p) = 1.461 plus or minus 0.077R sub( J) and M sub( p) = 0.805 plus or minus 0.068M sub( J). WASP-93b orbits its F4 host star every 2.73 d and has R sub( p) = 1.597 plus or minus 0.077R sub( J) and M sub( p) = 1.47 plus or minus 0.029M sub( J). WASP-118b also has a hot host star (F6) and is moderately inflated, where R sub( p) = 1.440 plus or minus 0.036R sub( J) and M sub( p) = 0.514 plus or minus 0.020M sub( J) and the planet has an orbital period of 4.05 d. They are bright targets (V = 13.18, 10.97 and 11.07, respectively) ideal for further characterization work, particularly WASP-118b, which is being observed by K2 as part of campaign 8. The WASP-93 system has sufficient angular momentum to be tidally migrating outwards if the system is near spin-orbit alignment, which is divergent from the tidal behaviour of the majority of hot Jupiters discovered.
Although curable, leprosy requires better diagnostic and prognostic tools to accompany therapeutic strategies. We evaluated the serum samples of leprosy patients from Venezuela and Brazil for ...reactivity against the specific recombinant proteins, ML0405 and ML2331, and the LID-1 fusion protein that incorporates both of these antigens. Antigen-specific IgG was highest in lepromatous leprosy patients (LL) and decreased across the disease spectrum, such that only a small subset of true tuberculoid patients (TT) tested positive. The impact of multidrug therapy (MDT) on these antibody responses was also examined. Several years after treatment, the vast majority of Venezuelan patients did not possess circulating anti-LID-1, anti-ML0405, and anti-ML2331 IgG, and the seropositivity of the remaining cases could be attributed to irregular treatment. At discharge, the magnitude and proportion of positive responses of Brazilian patients against the proteins and phenolic glycolipid (PGL)-I were lower for most of the clinical forms. The monthly examination of IgG levels in LL patient sera after MDT initiation indicated that these responses are significantly reduced during treatment. Thus, responses against these antigens positively correlate with bacillary load, clinical forms, and operational classification at diagnosis. Our data indicate that these responses could be employed as an auxiliary tool for the assessment of treatment efficacy and disease relapse.
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