The Deep Extragalactic VIsible Legacy Survey (DEVILS) is an ongoing high-completeness, deep spectroscopic survey of \(\sim\)60,000 galaxies to Y\(<\)21.2 mag, over \(\sim\)6 deg2 in three ...well-studied deep extragalactic fields: D10 (COSMOS), D02 (XMM-LSS) and D03 (ECDFS). Numerous DEVILS projects all require consistent, uniformly-derived and state-of-the-art photometric data with which to measure galaxy properties. Existing photometric catalogues in these regions either use varied photometric measurement techniques for different facilities/wavelengths leading to inconsistencies, older imaging data and/or rely on source detection and photometry techniques with known problems. Here we use the ProFound image analysis package and state-of-the-art imaging datasets (including Subaru-HSC, VST-VOICE, VISTA-VIDEO and UltraVISTA-DR4) to derive matched-source photometry in 22 bands from the FUV to 500{\mu}m. This photometry is found to be consistent, or better, in colour-analysis to previous approaches using fixed-size apertures (which are specifically tuned to derive colours), but produces superior total source photometry, essential for the derivation of stellar masses, star-formation rates, star-formation histories, etc. Our photometric catalogue is described in detail and, after internal DEVILS team projects, will be publicly released for use by the broader scientific community.
The remnant phase of a radio galaxy begins when the jets launched from an active galactic nucleus are switched off. To study the fraction of radio galaxies in a remnant phase, we take advantage of a ...\(8.31\)\,deg\(^2\) sub-region of the GAMA~23~field which comprises of surveys covering the frequency range 0.1--9\,GHz. We present a sample of 104 radio galaxies compiled from observations conducted by the Murchison Wide-field Array (216\,MHz), the Australia Square Kilometer Array Pathfinder (887\,MHz), and the Australia Telescope Compact Array (5.5\,GHz). We adopt an `absent radio core' criterion to identify 10 radio galaxies showing no evidence for an active nucleus. We classify these as new candidate remnant radio galaxies. Seven of these objects still display compact emitting regions within the lobes at 5.5\,GHz; at this frequency the emission is short-lived, implying a recent jet switch-off. On the other hand, only three show evidence of aged lobe plasma by the presence of an ultra-steep spectrum (\(\alpha<-1.2\)) and a diffuse, low surface-brightness radio morphology. The predominant fraction of young remnants is consistent with a rapid fading during the remnant phase. Within our sample of radio galaxies, our observations constrain the remnant fraction to \(4\%\lesssim f_{\mathrm{rem}} \lesssim 10\%\); the lower limit comes from the limiting case in which all remnant candidates with hotspots are simply active radio galaxies with faint, undetected radio cores. Finally, we model the synchrotron spectrum arising from a hotspot to show they can persist for 5--10\,Myr at 5.5\,GHz after the jets switch off -- radio emission arising from such hotspots can therefore be expected in an appreciable fraction of genuine remnants.
Galaxy gas kinematics are sensitive to the physical processes that contribute to a galaxy's evolution. It is expected that external processes will cause more significant kinematic disturbances in the ...outer regions, while internal processes will cause more disturbances for the inner regions. Using a subsample of 47 galaxies (\(0.27<z<0.36\)) from the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey, we conduct a study into the source of kinematic disturbances by measuring the asymmetry present in the ionised gas line-of-sight velocity maps at the \(0.5R_e\) (inner regions) and \(1.5R_e\) (outer regions) elliptical annuli. By comparing the inner and outer kinematic asymmetries, we aim to better understand what physical processes are driving the asymmetries in galaxies. We find the local environment plays a role in kinematic disturbance, in agreement with other integral field spectroscopy studies of the local universe, with most asymmetric systems being in close proximity to a more massive neighbour. We do not find evidence suggesting that hosting an Active Galactic Nucleus (AGN) contributes to asymmetry within the inner regions, with some caveats due to emission line modelling. In contrast to previous studies, we do not find evidence that processes leading to asymmetry also enhance star formation in MAGPI galaxies. Finally, we find a weak anti-correlation between stellar mass and asymmetry (ie. high stellar mass galaxies are less asymmetric). We conclude by discussing possible sources driving the asymmetry in the ionised gas, such as disturbances being present in the colder gas phase (either molecular or atomic) prior to the gas being ionised, and non-axisymmetric features (e.g., a bar) being present in the galactic disk. Our results highlight the complex interplay between ionised gas kinematic disturbances and physical processes involved in galaxy evolution.
We present an overview of the Middle Ages Galaxy Properties with Integral Field Spectroscopy (MAGPI) survey, a Large Program on ESO/VLT. MAGPI is designed to study the physical drivers of galaxy ...transformation at a lookback time of 3-4 Gyr, during which the dynamical, morphological, and chemical properties of galaxies are predicted to evolve significantly. The survey uses new medium-deep adaptive optics aided MUSE observations of fields selected from the GAMA survey, providing a wealth of publicly available ancillary multi-wavelength data. With these data, MAGPI will map the kinematic and chemical properties of stars and ionised gas for a sample of 60 massive (> 7 x 10^10 M_Sun) central galaxies at 0.25 < z <0.35 in a representative range of environments (isolated, groups and clusters). The spatial resolution delivered by MUSE with Ground Layer Adaptive Optics (GLAO, 0.6-0.8 arcsec FWHM) will facilitate a direct comparison with Integral Field Spectroscopy surveys of the nearby Universe, such as SAMI and MaNGA, and at higher redshifts using adaptive optics, e.g. SINS. In addition to the primary (central) galaxy sample, MAGPI will deliver resolved and unresolved spectra for as many as 150 satellite galaxies at 0.25 < z <0.35, as well as hundreds of emission-line sources at z < 6. This paper outlines the science goals, survey design, and observing strategy of MAGPI. We also present a first look at the MAGPI data, and the theoretical framework to which MAGPI data will be compared using the current generation of cosmological hydrodynamical simulations including EAGLE, Magneticum, HORIZON-AGN, and Illustris-TNG. Our results show that cosmological hydrodynamical simulations make discrepant predictions in the spatially resolved properties of galaxies at z ~ 0.3. MAGPI observations will place new constraints and allow for tangible improvements in galaxy formation theory.
We present early science results from the First Large Absorption Survey in HI (FLASH), a spectroscopically blind survey for 21-cm absorption lines in cold hydrogen HI gas at cosmological distances ...using the Australian Square Kilometre Array Pathfinder (ASKAP). We have searched for HI absorption towards 1253 radio sources in the GAMA 23 field, covering redshifts between \(z = 0.34\) and \(0.79\) over a sky area of approximately 50 deg\(^{2}\). In a purely blind search we did not obtain any detections of 21-cm absorbers above our reliability threshold. Assuming a fiducial value for the HI spin temperature of \(T_{\rm spin}\) = 100 K and source covering fraction \(c_{\rm f} = 1\), the total comoving absorption path length sensitive to all Damped Lyman \(\alpha\) Absorbers (DLAs; \(N_{\rm HI} \geq 2 \times 10^{20}\) cm\(^{-2}\)) is \(\Delta{X} = 6.6 \pm 0.3\) (\(\Delta{z} = 3.7 \pm 0.2\)) and super-DLAs (\(N_{\rm HI} \geq 2 \times 10^{21}\) cm\(^{-2}\)) is \(\Delta{X} = 111 \pm 6\) (\(\Delta{z} = 63 \pm 3\)). We estimate upper limits on the HI column density frequency distribution function that are consistent with measurements from prior surveys for redshifted optical DLAs, and nearby 21-cm emission and absorption. By cross matching our sample of radio sources with optical spectroscopic identifications of galaxies in the GAMA 23 field, we were able to detect 21-cm absorption at \(z = 0.3562\) towards NVSS J224500\(-\)343030, with a column density of \(N_{\rm HI} = (1.2 \pm 0.1) \times 10^{20} (T_{\rm spin}/100~\mathrm{K})\) cm\(^{-2}\). The absorber is associated with GAMA J22450.05\(-\)343031.7, a massive early-type galaxy at an impact parameter of 17 kpc with respect to the radio source and which may contain a massive (\(M_{\rm HI} \gtrsim 3 \times 10^{9}\) M\(_{\odot}\)) gas disc. Such gas-rich early types are rare, but have been detected in the nearby Universe.
We present the evolution of the star-formation dispersion - stellar mass relation (\(\sigma_{SFR}\)-M\(_{\star}\)) in the DEVILS D10 region using new measurements derived using the ProSpect spectral ...energy distribution fitting code. We find that \(\sigma_{SFR}\)-M\(_{\star}\) shows the characteristic 'U-shape' at intermediate stellar masses from 0.1<z<0.7 for a number of metrics, including using the deconvolved intrinsic dispersion. A physical interpretation of this relation is the combination of stochastic star-formation and stellar feedback causing large scatter at low stellar masses and AGN feedback causing asymmetric scatter at high stellar masses. As such, the shape of this distribution and its evolution encodes detailed information about the astrophysical processes affecting star-formation, feedback and the lifecycle of galaxies. We find that the stellar mass that the minimum \({\sigma}_{SFR}\) occurs evolves linearly with redshift, moving to higher stellar masses with increasing lookback time and traces the turnover in the star-forming sequence. This minimum \({\sigma}_{SFR}\) point is also found to occur at a fixed specific star-formation rate (sSFR) at all epochs (sSFR~10\(^{-9.6}\)yr\(^{-1}\)). The physical interpretation of this is that there exists a maximum sSFR at which galaxies can internally self-regulate on the tight sequence of star-formation. At higher sSFRs, stochastic stellar processes begin to cause galaxies to be pushed both above and below the star-forming sequence leading to increased SFR dispersion. As the Universe evolves, a higher fraction of galaxies will drop below this sSFR threshold, causing the dispersion of the low-stellar mass end of the star-forming sequence to decrease with time.
Circular dichroism (CD) spectroscopy is one of the most versatile tools to study protein folding and to validate the proper fold of purified proteins. Here, we aim to provide a readily accessible, ...user-friendly and platform-independent tool capable of analysing multiple CD datasets of virtually any format and returning results as high-quality graphical output to the user.
CAPITO (CD Anaylsis and Plotting Tool) is a novel web server-based tool for analysing and plotting CD data. It allows reliable estimation of secondary structure content utilizing different approaches. CAPITO accepts multiple CD datasets and, hence, is well suited for a wide application range such as the analysis of temperature or pH-dependent (un)folding and the comparison of mutants.
http://capito.nmr.fli-leibniz.de.
cwiede@fli-leibniz.de or mago@fli-leibniz.de
Supplementary data are available at Bioinformatics online.
Potato virus Y (PVY) is an important plant pathogen, whose host range includes economically important crops such as potato, tobacco, tomato, and pepper. PVY presents three main strains (PVY(O), ...PVY(N) and PVY(C)) and several recombinant forms. PVY has a worldwide distribution, yet the mechanisms that promote and maintain its population structure and genetic diversity are still unclear. In this study, we used a pool of 77 complete PVY genomes from isolates collected worldwide. After removing the effect of recombination in our data set, we used bayesian techniques to study the influence of geography and host species in both PVY population structure and dynamics. We have also performed selection and covariation analyses to identify evolutionarily relevant amino acid residues. Our results show that both geographic and host-driven adaptations explain PVY diversification. Furthermore, purifying selection is the main force driving PVY evolution, although some indications of positive selection accounted for the diversification of the different strains. Interestingly, the analysis of P3N-PIPO, a recently described gene in potyviruses, seems to show a variable length among the isolates analyzed, and this variability is explained, in part, by host-driven adaptation.
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•The phylogenetic positions of many African Orchideae (Orchidaceae) are resolved.•Three main clades were identified: Bartholininae, Orchidinae s.s. and Habenariinae.•The first lineage ...includes Bartholina and Holothrix, and forms a sister clade to the two latter clades.•Orchidinae and Habenariinae were recovered with a similar generic composition as in their historical circumscription.•We proposed a more stable classification for the tribe Orchideae s.l.
Phylogenetic relationships within the Orchideae sensu Pridgeon et al, remain one of the biggest unresolved issues in our understanding of the taxonomy of the orchids. Members of the Orchideae are numerous and widespread in Africa but remain poorly represented in phylogenetic research. In this study we included a broad sampling of African taxa for which we sequenced three plastid (rbcl, matK and trnL + trnL-F) and two nuclear regions (ITS and 18S). We used 368 sequences representing 278 species and 49 genera to infer relationships using the Bayesian Inference and Maximum Likelihood method. Our results show strong support for three clades, two of which almost entirely match the historical circumscription of Orchidinae and Habenariinae, and the third, Bartholininae, sister to the former two, includes the genera Holothrix and Bartholina. Stenoglottis should be assigned to Orchidinae and not to Habenariinae. Several genera such as Habenaria, Cynorkis and Benthamia are shown to be para- or polyphyletic: Bonatea, Centrostigma, Platycoryne and Roeperocharis are all embedded in Habenaria; Physoceras, Arnottia and part of Benthamia are embedded in Cynorkis. We propose a subdivision of Orchideae sensu lato into nine subtribes, but refrain from making generic re-arrangements until more extensive or more in-depth studies have been done.
It is widely recognized that we are entering an extinction event on a scale approaching the mass extinctions seen in the fossil record. Present-day rates of extinction are estimated to be several ...orders of magnitude greater than background rates and are projected to increase further if current trends continue. In vertebrates, species traits, such as body size, fecundity, and geographic range, are important predictors of vulnerability. Although plants are the basis for life on Earth, our knowledge of plant extinctions and vulnerabilities is lagging. Here, we disentangle the underlying drivers of extinction risk in plants, focusing on the Cape of South Africa, a global biodiversity hotspot. By comparing Red List data for the British and South African floras, we demonstrate that the taxonomic distribution of extinction risk differs significantly between regions, inconsistent with a simple, trait-based model of extinction. Using a comprehensive phylogenetic tree for the Cape, we reveal a phylogenetic signal in the distribution of plant extinction risks but show that the most threatened species cluster within short branches at the tips of the phylogeny--opposite to trends in mammals. From analyzing the distribution of threatened species across 11 exemplar clades, we suggest that mode of speciation best explains the unusual phylogenetic structure of extinction risks in plants of the Cape. Our results demonstrate that explanations for elevated extinction risk in plants of the Cape flora differ dramatically from those recognized for vertebrates. In the Cape, extinction risk is higher for young and fast-evolving plant lineages and cannot be explained by correlations with simple biological traits. Critically, we find that the most vulnerable plant species are nonetheless marching towards extinction at a more rapid pace but, surprisingly, independently from anthropogenic effects. Our results have important implications for conservation priorities and cast doubts on the utility of current Red List criteria for plants in regions such as the Cape, where speciation has been rapid, if our aim is to maximize the preservation of the tree-of-life.
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