Abstract
We describe the selection of galaxies targeted in eight low-redshift clusters (APMCC0917, A168, A4038, EDCC442, A3880, A2399, A119 and A85; 0.029 < z < 0.058) as part of the Sydney-AAO ...Multi-Object Integral field spectrograph Galaxy Survey (SAMI-GS). We have conducted a redshift survey of these clusters using the AAOmega multi-object spectrograph on the 3.9-m Anglo-Australian Telescope. The redshift survey is used to determine cluster membership and to characterize the dynamical properties of the clusters. In combination with existing data, the survey resulted in 21 257 reliable redshift measurements and 2899 confirmed cluster member galaxies. Our redshift catalogue has a high spectroscopic completeness (∼94 per cent) for rpetro ≤ 19.4 and cluster-centric distances R < 2R200. We use the confirmed cluster member positions and redshifts to determine cluster velocity dispersion, R200, virial and caustic masses, as well as cluster structure. The clusters have virial masses 14.25 ≤ log(M200/M⊙) ≤ 15.19. The cluster sample exhibits a range of dynamical states, from relatively relaxed-appearing systems, to clusters with strong indications of merger-related substructure. Aperture- and point spread function matched photometry are derived from Sloan Digital Sky Survey and VLT Survey Telescope/ATLAS imaging and used to estimate stellar masses. These estimates, in combination with the redshifts, are used to define the input target catalogue for the cluster portion of the SAMI-GS. The primary SAMI-GS cluster targets have R <R200, velocities |vpec| < 3.5σ200 and stellar masses $9.5 \le {\rm log({\it M}}^*_{{\rm approx}}/$M⊙)≤12. Finally, we give an update on the SAMI-GS progress for the cluster regions.
Biofabrication is providing scientists and clinicians the ability to produce engineered tissues with desired shapes and gradients of composition and biological cues. Typical resolutions achieved with ...extrusion-based bioprinting are at the macroscopic level. However, for capturing the fibrillar nature of the extracellular matrix (ECM), it is necessary to arrange ECM components at smaller scales, down to the micron and the molecular level. Herein, we introduce a bioink containing the tyramine derivative of hyaluronan (HA; henceforth known as THA) and collagen (Col) type 1. In this bioink, similar to connective tissues, Col is present in the fibrillar form, and HA functions as a viscoelastic space filler. THA was enzymatically cross-linked under mild conditions allowing simultaneous Col fibrillogenesis, thus achieving a homogeneous distribution of Col fibrils within the viscoelastic HA-based matrix. The THA-Col composite displayed synergistic properties in terms of storage modulus and shear thinning, translating into good printability. Shear-induced alignment of the Col fibrils along the printing direction was achieved and quantified via immunofluorescence and second-harmonic generation. Cell-free and cell-laden constructs were printed and characterized, analyzing the influence of the controlled microscopic anisotropy on human bone marrow–derived mesenchymal stromal cell (hMSC) migration. Anisotropic HA-Col showed cell-instructive properties modulating hMSC adhesion, morphology, and migration from micropellets stimulated by the presence and the orientation of Col fibers. Actin filament staining showed that hMSCs embedded in aligned constructs displayed increased cytoskeleton alignment along the fibril direction. Based on gene expression of cartilage/bone markers and ECM production, hMSCs embedded in the isotropic bioink displayed chondrogenic differentiation comparable with standard pellet culture by means of proteoglycan production (safranin O staining and proteoglycan quantification). The possibility of printing matrix components with control over microscopic alignment brings biofabrication one step closer to capturing the complexity of native tissues.
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•Fabrication of a tissue mimetic collagen I-hyaluronan bioink.•Three-dimensional printing to control microscopic alignment of fibrillar collagen.•The control over collagen fibril orientation allows to modulate cell alignment.•The composite biomaterial showed a prochondrogenic potential.
Context. Evolved low-mass stars lose a significant fraction of their mass through stellar winds. While the overall morphology of the stellar wind structure during the asymptotic giant branch (AGB) ...phase is thought to be roughly spherically symmetric, the morphology changes dramatically during the post-AGB and planetary nebula phase, during which bipolar and multi-polar structures are often observed. Aims. We aim to study the inner wind structure of the closest well-known AGB star CW Leo. Different diagnostics probing different geometrical scales have implied a non-homogeneous mass-loss process for this star: dust clumps are observed at milli-arcsec scale, a bipolar structure is seen at arcsecond-scale, and multi-concentric shells are detected beyond 1′′. Methods. We present the first ALMA Cycle 0 band 9 data around 650 GHz (450 μm) tracing the inner wind of CW Leo. The full-resolution data have a spatial resolution of 0.̋42 × 0.̋24, allowing us to study the morpho-kinematical structure of CW Leo within ~6′′. Results. We have detected 25 molecular emission lines in four spectral windows. The emission of all but one line is spatially resolved. The dust and molecular lines are centered around the continuum peak position, which is assumed to be dominated by stellar emission. The dust emission has an asymmetric distribution with a central peak flux density of ~2 Jy. The molecular emission lines trace different regions in the wind acceleration region and imply that the wind velocity increases rapidly from about 5 R⋆, almost reaching the terminal velocity at ~11 R⋆. The images prove that vibrational lines are excited close to the stellar surface and that SiO is a parent molecule. The channel maps for the brighter lines show a complex structure; specifically, for the 13CO J = 6–5 line, different arcs are detected within the first few arcseconds. The curved structure in the position-velocity (PV) map of the 13CO J = 6–5 line can be explained by a spiral structure in the inner wind of CW Leo, probably induced by a binary companion. From modelling the ALMA data, we deduce that the potential orbital axis for the binary system lies at a position angle of ~10–20° to the north-east and that the spiral structure is seen almost edge-on. We infer an orbital period of 55 yr and a binary separation of 25 au (or ~8.2 R⋆). We tentatively estimate that the companion is an unevolved low-mass main-sequence star. Conclusions. A scenario of a binary-induced spiral shell can explain the correlated structure seen in the ALMA PV images of CW Leo. Moreover, this scenario can also explain many other observational signatures seen at different spatial scales and in different wavelength regions, such as the bipolar structure and the almost concentric shells. ALMA data hence for the first time provide the crucial kinematical link between the dust clumps seen at milli-arcsecond scale and the almost concentric arcs seen at arcsecond scale.
We have developed a simple method for calculating the ionospheric photoelectron flux that uses the concept of average electron energy loss to simplify the calculation of the degraded electron ...spectrum. This method, which requires only a knowledge of the total inelastic electron impact cross sections, rather than a detailed knowledge of the many partial cross sections can be used for the calculation of all secondary ion and excited state production rates. We estimate that the use of an average energy loss reduces the computation time by a factor of 10 and considerably reduces storage requirements. The simple model is designed to provide ionospheric chemistry workers with a convenient means of obtaining photoelectron spectra similar to that which is currently available for obtaining neutral densities. It is shown that the ionospheric photoelectron flux in the local equilibrium region is directly proportional to the attenuated solar EUV flux, which is a function only of the total neutral column density, and is independent of the neutral density composition. Therefore, electron impact cross sections can be chosen so that the simple method may also be used to parameterize the measured ionospheric photoelectron fluxes.
Inhibition of the Wnt antagonist sclerostin increases bone mass in patients with osteoporosis and in preclinical animal models. Here we show increased levels of the Wnt antagonist Dickkopf-1 (DKK-1) ...in animals treated with sclerostin antibody, suggesting a negative feedback mechanism that limits Wnt-driven bone formation. To test our hypothesis that co-inhibition of both factors further increases bone mass, we engineer a first-in-class bispecific antibody with single residue pair mutations in the Fab region to promote efficient and stable cognate light-heavy chain pairing. We demonstrate that dual inhibition of sclerostin and DKK-1 leads to synergistic bone formation in rodents and non-human primates. Furthermore, by targeting distinct facets of fracture healing, the bispecific antibody shows superior bone repair activity compared with monotherapies. This work supports the potential of this agent both for treatment and prevention of fractures and offers a promising therapeutic approach to reduce the burden of low bone mass disorders.
Gaia Early Data Release 3 Riello, M.; De Angeli, F.; Evans, D. W. ...
Astronomy and astrophysics (Berlin),
05/2021, Letnik:
649
Journal Article
Recenzirano
Odprti dostop
Context. Gaia
Early Data Release 3 (
Gaia
EDR3) contains astrometry and photometry results for about 1.8 billion sources based on observations collected by the European Space Agency
Gaia
satellite ...during the first 34 months of its operational phase.
Aims.
In this paper, we focus on the photometric content, describing the input data, the algorithms, the processing, and the validation of the results. Particular attention is given to the quality of the data and to a number of features that users may need to take into account to make the best use of the
Gaia
EDR3 catalogue.
Methods.
The processing broadly followed the same procedure as for
Gaia
DR2, but with significant improvements in several aspects of the blue and red photometer (BP and RP) preprocessing and in the photometric calibration process. In particular, the treatment of the BP and RP background has been updated to include a better estimation of the local background, and the detection of crowding effects has been used to exclude affected data from the calibrations. The photometric calibration models have also been updated to account for flux loss over the whole magnitude range. Significant improvements in the modelling and calibration of the
Gaia
point and line spread functions have also helped to reduce a number of instrumental effects that were still present in DR2.
Results. Gaia
EDR3 contains 1.806 billion sources with
G
-band photometry and 1.540 billion sources with
G
BP
and
G
RP
photometry. The median uncertainty in the
G
-band photometry, as measured from the standard deviation of the internally calibrated mean photometry for a given source, is 0.2 mmag at magnitude
G
= 10–14, 0.8 mmag at
G
≈ 17, and 2.6 mmag at
G
≈ 19. The significant magnitude term found in the
Gaia
DR2 photometry is no longer visible, and overall there are no trends larger than 1 mmag mag
−1
. Using one passband over the whole colour and magnitude range leaves no systematics above the 1% level in magnitude in any of the bands, and a larger systematic is present for a very small sample of bright and blue sources. A detailed description of the residual systematic effects is provided. Overall the quality of the calibrated mean photometry in
Gaia
EDR3 is superior with respect to DR2 for all bands.
A number of large, rare copy number variants (CNVs) are deleterious for neurodevelopmental disorders, but large, rare, protective CNVs have not been reported for such phenotypes. Here we show in a ...CNV analysis of 47 005 individuals, the largest CNV analysis of schizophrenia to date, that large duplications (1.5-3.0 Mb) at 22q11.2--the reciprocal of the well-known, risk-inducing deletion of this locus--are substantially less common in schizophrenia cases than in the general population (0.014% vs 0.085%, OR=0.17, P=0.00086). 22q11.2 duplications represent the first putative protective mutation for schizophrenia.
Abstract Emission lines from Rydberg transitions are detected for the first time from a region close to the surface of Betelgeuse. The H30 α line is observed at 231.905 GHz, with an FWHM ∼42 km s −1 ...and extended wings. A second line at 232.025 GHz (FWHM ∼21 km s −1 ), is modeled as a combination of Rydberg transitions of abundant low first ionization potential metals. Both H30 α and the Rydberg combined line X30 α are fitted by Voigt profiles, and collisional broadening with electrons may be partly responsible for the Lorentzian contribution, indicating electron densities of a few 10 8 cm −3 . X30 α is located in a relatively smooth ring at a projected radius of 0.9× the optical photospheric radius R ⋆ , whereas H30 α is more clumpy, reaching a peak at ∼1.4 R ⋆ . We use a semiempirical thermodynamic atmospheric model of Betelgeuse to compute the 232 GHz (1.29 mm) continuum and line profiles making simple assumptions. Photoionized abundant metals dominate the electron density, and the predicted surface of continuum optical depth unity at 232 GHz occurs at ∼1.3 R ⋆ , in good agreement with observations. Assuming a Saha–Boltzmann distribution for the level populations of Mg, Si, and Fe, the model predicts that the X30 α emission arises in a region of radially increasing temperature and turbulence. Inclusion of ionized C and non-LTE effects could modify the integrated fluxes and location of emission. These simulations confirm the identity of the Rydberg transition lines observed toward Betelgeuse and reveal that such diagnostics can improve future atmospheric models.
Lymphoma is the leading cause of cancer-related death among HIV-infected patients in the antiretroviral therapy (ART) era.
We studied lymphoma patients in the Centers for AIDS Research Network of ...Integrated Clinical Systems from 1996 until 2010. We examined differences stratified by histology and diagnosis year. Mortality and predictors of death were analyzed using Kaplan-Meier curves and Cox proportional hazards.
Of 23 050 HIV-infected individuals, 476 (2.1%) developed lymphoma (79 16.6% Hodgkin lymphoma HL; 201 42.2% diffuse large B-cell lymphoma DLBCL; 56 11.8% Burkitt lymphoma BL; 54 11.3% primary central nervous system lymphoma PCNSL; and 86 18.1% other non-Hodgkin lymphoma NHL). At diagnosis, HL patients had higher CD4 counts and lower HIV RNA than NHL patients. PCNSL patients had the lowest and BL patients had the highest CD4 counts among NHL categories. During the study period, CD4 count at lymphoma diagnosis progressively increased and HIV RNA decreased. Five-year survival was 61.6% for HL, 50.0% for BL, 44.1% for DLBCL, 43.3% for other NHL, and 22.8% for PCNSL. Mortality was associated with age (adjusted hazard ratio AHR = 1.28 per decade increase, 95% confidence interval CI = 1.06 to 1.54), lymphoma occurrence on ART (AHR = 2.21, 95% CI = 1.53 to 3.20), CD4 count (AHR = 0.81 per 100 cell/µL increase, 95% CI = 0.72 to 0.90), HIV RNA (AHR = 1.13 per log10copies/mL, 95% CI = 1.00 to 1.27), and histology but not earlier diagnosis year.
HIV-associated lymphoma is heterogeneous and changing, with less immunosuppression and greater HIV control at diagnosis. Stable survival and increased mortality for lymphoma occurring on ART call for greater biologic insights to improve outcomes.
Historical mining of uranium mineral veins within Cornwall, England, has resulted in a significant amount of legacy radiological contamination spread across numerous long disused mining sites. ...Factors including the poorly documented and aged condition of these sites as well as the highly localised nature of radioactivity limit the success of traditional survey methods. A newly developed terrain-independent unmanned aerial system UAS carrying an integrated gamma radiation mapping unit was used for the radiological characterisation of a single legacy mining site. Using this instrument to produce high-spatial-resolution maps, it was possible to determine the radiologically contaminated land areas and to rapidly identify and quantify the degree of contamination and its isotopic nature. The instrument was demonstrated to be a viable tool for the characterisation of similar sites worldwide.
•We provide a high spatial resolution radiation map of a legacy uranium mining site.•We use a terrain independent UAS to provide the mapping.•Data is favourably comparable with ground-based radiation mapping.•The improved spatial resolution will increase the quality of future aerial surveys.
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