Adipose-derived stromal cells (ASC) are promising candidates for cell therapy, for example to treat myocardial infarction. Commonly, fetal bovine serum (FBS) is used in ASC culturing. However, FBS ...has several disadvantages. Its effects differ between batches and, when applied clinically, transmission of pathogens and antibody development against FBS are possible. In this study, we investigated whether FBS can be substituted by human platelet lysate (PL) in ASC culture, without affecting functional capacities particularly important for cardiac repair application of ASC. We found that PL-cultured ASC had a significant 3-fold increased proliferation rate and a significantly higher attachment to tissue culture plastic as well as to endothelial cells compared with FBS-cultured ASC. PL-cultured ASC remained a significant 25% smaller than FBS-cultured ASC. Both showed a comparable surface marker profile, with the exception of significantly higher levels of CD73, CD90, and CD166 on PL-cultured ASC. PL-cultured ASC showed a significantly higher migration rate compared with FBS-cultured ASC in a transwell assay. Finally, FBS- and PL-cultured ASC had a similar high capacity to differentiate towards cardiomyocytes. In conclusion, this study showed that culturing ASC is more favorable in PL-supplemented medium compared with FBS-supplemented medium.
We present cosmological parameter constraints from a tomographic weak gravitational lensing analysis of ~450 deg super( 2) of imaging data from the Kilo Degree Survey (KiDS). For a flat ... cold dark ...matter (...CDM) cosmology with a prior on H sub( 0) that encompasses the most recent direct measurements, we find S sub( 8) ... = 0.745 plus or minus 0.039. This result is in good agreement with other low-redshift probes of large-scale structure, including recent cosmic shear results, along with pre-Planck cosmic microwave background constraints. A 2.3... tension in S sub( 8) and 'substantial discordance' in the full parameter space is found with respect to the Planck 2015 results. We use shear measurements for nearly 15 million galaxies, determined with a new improved 'self-calibrating' version of lensfit validated using an extensive suite of image simulations. Four-band ugri photometric redshifts are calibrated directly with deep spectroscopic surveys. The redshift calibration is confirmed using two independent techniques based on angular cross-correlations and the properties of the photometric redshift probability distributions. Our covariance matrix is determined using an analytical approach, verified numerically with large mock galaxy catalogues. We account for uncertainties in the modelling of intrinsic galaxy alignments and the impact of baryon feedback on the shape of the non-linear matter power spectrum, in addition to the small residual uncertainties in the shear and redshift calibration. The cosmology analysis was performed blind. Our high-level data products, including shear correlation functions, covariance matrices, redshift distributions, and Monte Carlo Markov chains are available at http://kids.strw.leidenuniv.nl. (ProQuest: ... denotes formulae/symbols omitted.)
We present a tomographic cosmic shear analysis of the Kilo-Degree Survey (KiDS) combined with the VISTA Kilo-Degree Infrared Galaxy Survey. This is the first time that a full optical to near-infrared ...data set has been used for a wide-field cosmological weak lensing experiment. This unprecedented data, spanning 450 deg 2 , allows us to significantly improve the estimation of photometric redshifts, such that we are able to include robustly higher-redshift sources for the lensing measurement, and – most importantly – to solidify our knowledge of the redshift distributions of the sources. Based on a flat ΛCDM model we find S 8 ≡ σ 8 Ω m /0.3 = 0.737 +0.040 −0.036 in a blind analysis from cosmic shear alone. The tension between KiDS cosmic shear and the Planck-Legacy CMB measurements remains in this systematically more robust analysis, with S 8 differing by 2.3 σ . This result is insensitive to changes in the priors on nuisance parameters for intrinsic alignment, baryon feedback, and neutrino mass. KiDS shear measurements are calibrated with a new, more realistic set of image simulations and no significant B-modes are detected in the survey, indicating that systematic errors are under control. When calibrating our redshift distributions by assuming the 30-band COSMOS-2015 photometric redshifts are correct (following the Dark Energy Survey and the Hyper Suprime-Cam Survey), we find the tension with Planck is alleviated. The robust determination of source redshift distributions remains one of the most challenging aspects for future cosmic shear surveys.
We present redshift distribution estimates of galaxies selected from the fourth data release of the Kilo-Degree Survey over an area of ∼1000 deg 2 (KiDS-1000). These redshift distributions represent ...one of the crucial ingredients for weak gravitational lensing measurements with the KiDS-1000 data. The primary estimate is based on deep spectroscopic reference catalogues that are re-weighted with the help of a self-organising map (SOM) to closely resemble the KiDS-1000 sources, split into five tomographic redshift bins in the photometric redshift range 0.1 < z B ≤ 1.2. Sources are selected such that they only occupy that volume of nine-dimensional magnitude-space that is also covered by the reference samples (‘gold’ selection). Residual biases in the mean redshifts determined from this calibration are estimated from mock catalogues to be ≲0.01 for all five bins with uncertainties of ∼0.01. This primary SOM estimate of the KiDS-1000 redshift distributions is complemented with an independent clustering redshift approach. After validation of the clustering- z on the same mock catalogues and a careful assessment of systematic errors, we find no significant bias of the SOM redshift distributions with respect to the clustering- z measurements. The SOM redshift distributions re-calibrated by the clustering- z represent an alternative calibration of the redshift distributions with only slightly larger uncertainties in the mean redshifts of ∼0.01 − 0.02 to be used in KiDS-1000 cosmological weak lensing analyses. As this includes the SOM uncertainty, clustering- z are shown to be fully competitive on KiDS-1000 data.
ABSTRACT
We present a new sample of galaxy-scale strong gravitational lens candidates, selected from 904 deg2 of Data Release 4 of the Kilo-Degree Survey, i.e. the ‘Lenses in the Kilo-Degree Survey’ ...(LinKS) sample. We apply two convolutional neural networks (ConvNets) to ${\sim }88\,000$ colour–magnitude-selected luminous red galaxies yielding a list of 3500 strong lens candidates. This list is further downselected via human inspection. The resulting LinKS sample is composed of 1983 rank-ordered targets classified as ‘potential lens candidates’ by at least one inspector. Of these, a high-grade subsample of 89 targets is identified with potential strong lenses by all inspectors. Additionally, we present a collection of another 200 strong lens candidates discovered serendipitously from various previous ConvNet runs. A straightforward application of our procedure to future Euclid or Large Synoptic Survey Telescope data can select a sample of ∼3000 lens candidates with less than 10 per cent expected false positives and requiring minimal human intervention.
We present five new satellites of the Milky Way discovered in Sloan Digital Sky Survey (SDSS) imaging data, four of which were followed up with either the Subaru or the Isaac Newton Telescopes. They ...include four probable new dwarf galaxies--one each in the constellations of Coma Berenices, Canes Venatici, Leo, and Hercules--together with one unusually extended globular cluster, Segue 1. We provide distances, absolute magnitudes, half-light radii, and color-magnitude diagrams for all five satellites. The morphological features of the color-magnitude diagrams are generally well described by the ridge line of the old, metal-poor globular cluster M92. In the past two years, a total of 10 new Milky Way satellites with effective surface brightness k sub(u) 28 mag arcsec super(-2) have been discovered in SDSS data. They are less luminous, more irregular, and apparently more metal-poor than the previously known nine Milky Way dwarf spheroidals. The relationship between these objects and other populations is discussed. We note that there is a paucity of objects with half-light radii between 640 and 6100 pc. We conjecture that this may represent the division between star clusters and dwarf galaxies.
Context. The Kilo-Degree Survey (KiDS) is an ongoing optical wide-field imaging survey with the OmegaCAM camera at the VLT Survey Telescope, specifically designed for measuring weak gravitational ...lensing by galaxies and large-scale structure. When completed it will consist of 1350 square degrees imaged in four filters (ugri). Aims. Here we present the fourth public data release which more than doubles the area of sky covered by data release 3. We also include aperture-matched ZYJHKs photometry from our partner VIKING survey on the VISTA telescope in the photometry catalogue. We illustrate the data quality and describe the catalogue content. Methods. Two dedicated pipelines are used for the production of the optical data. The ASTRO-WISE information system is used for the production of co-added images in the four survey bands, while a separate reduction of the r-band images using the THELI pipeline is used to provide a source catalogue suitable for the core weak lensing science case. All data have been re-reduced for this data release using the latest versions of the pipelines. The VIKING photometry is obtained as forced photometry on the THELI sources, using a re-reduction of the VIKING data that starts from the VISTA pawprints. Modifications to the pipelines with respect to earlier releases are described in detail. The photometry is calibrated to the Gaia DR2 G band using stellar locus regression. Results. In this data release a total of 1006 square-degree survey tiles with stacked ugri images are made available, accompanied by weight maps, masks, and single-band source lists. We also provide a multi-band catalogue based on r-band detections, including homogenized photometry and photometric redshifts, for the whole dataset. Mean limiting magnitudes (5σ in a 2″ aperture) and the tile-to-tile rms scatter are 24.23 ± 0.12, 25.12 ± 0.14, 25.02 ± 0.13, 23.68 ± 0.27 in ugri, respectively, and the mean r-band seeing is 0.″70.
The Kilo-Degree Survey is an optical wide-field survey designed to map the matter distribution in the Universe using weak gravitational lensing. In this paper, we use these data to measure the ...density profiles and masses of a sample of ∼1400 spectroscopically identified galaxy groups and clusters from the Galaxy And Mass Assembly survey. We detect a highly significant signal (signal-to-noise-ratio ∼120), allowing us to study the properties of dark matter haloes over one and a half order of magnitude in mass, from M ∼ 1013–1014.5 h
−1 M⊙. We interpret the results for various subsamples of groups using a halo model framework which accounts for the mis-centring of the brightest cluster galaxy (used as the tracer of the group centre) with respect to the centre of the group's dark matter halo. We find that the density profiles of the haloes are well described by an NFW profile with concentrations that agree with predictions from numerical simulations. In addition, we constrain scaling relations between the mass and a number of observable group properties. We find that the mass scales with the total r-band luminosity as a power law with slope 1.16 ± 0.13 (1σ) and with the group velocity dispersion as a power law with slope 1.89 ± 0.27 (1σ). Finally, we demonstrate the potential of weak lensing studies of groups to discriminate between models of baryonic feedback at group scales by comparing our results with the predictions from the Cosmo-OverWhelmingly Large Simulations project, ruling out models without AGN feedback.
In patients with metastatic neuroendocrine neoplasms, the liver is the most commonly affected organ and a crucial factor for prognosis and survival. Peptide receptor radionuclide therapy can prolong ...progression-free survival in these patients. Additional treatment of liver disease might further improve outcomes. We aimed to investigate the safety and efficacy of additional holmium-166 (166Ho) radioembolisation after peptide receptor radionuclide therapy in patients with metastatic liver neuroendocrine neoplasms.
The Holmium Embolization Particles for Arterial Radiotherapy Plus 177Lu-Dotatate in Salvage Neuroendocrine Tumour Patients (HEPAR PLuS) study was a single-centre, phase 2 study done at the University Medical Center Utrecht (Utrecht, Netherlands). Patients, aged at least 18 years, with histologically proven grade 1 or 2 neuroendocrine neoplasms of all origins, an Eastern Cooperative Oncology Group performance status of 0–2, and three or more measurable liver metastases according to Response Evaluation Criteria In Solid Tumors (RECIST) version 1.1 criteria received 166Ho-radioembolisation within 20 weeks after four cycles of peptide receptor radionuclide therapy (lutetium-177-dotatate 177Lu-dotatate). The primary endpoint was objective liver tumour response in the treated liver volume, defined as complete response (disappearance of all lesions) or partial response (≥30% decrease in the sum of the longest diameters of the target lesions, compared with baseline measurements), according to RECIST 1.1, analysed per protocol at 3 months. Safety was assessed in all patients who received treatment. This study is registered with ClinicalTrials.gov, NCT02067988. Recruitment is completed and long-term follow-up is ongoing.
From Oct 15, 2014, to Sept 12, 2018, 34 patients were assessed for eligibility. 31 patients received treatment and 30 (97%) patients were available for primary endpoint assessment and completed 6 months of follow-up. Three (9%) patients were excluded at screening and one (3%) patient was treated and died before the primary endpoint and was replaced. According to the per-protocol analysis 13 (43%; 95% CI 26–63) of 30 patients achieved an objective response in the treated volume. The most frequently reported Common Terminology Criteria for Adverse Events (CTCAE) grade 3–4 clinical and laboratory toxicities within 6 months included abdominal pain (three 10% of 31 patients), increased γ-glutamyl transpeptidase (16 54%), and lymphocytopenia (seven 23%). One (3%) fatal treatment-related serious adverse event occurred (radioembolisation-induced liver disease). Two (6%) patients had serious adverse events deemed to be unrelated to treatment (gastric ulcer and perforated cholecystitis).
166Ho-radioembolisation, as an adjunct to peptide receptor radionuclide therapy in patients with neuroendocrine neoplasm liver metastases, is safe and efficacious. Radioembolisation can be considered in patients with bulky liver disease, including after peptide receptor radionuclide therapy. A future randomised, controlled study should investigate the added benefit of this treatment on progression-free survival.
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