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We investigate the diversity in the sizes and average surface densities of the neutral atomic hydrogen (HI) gas discs in ~280 nearby galaxies detected by the Widefield ASKAP L-band Legacy All-sky Blind Survey (WALLABY). We combine the uniformly observed, interferometric HI data from pilot observations of the Hydra cluster and NGC 4636 group fields with photometry measured from ultraviolet, optical and near-infrared imaging surveys to investigate the interplay between stellar structure, star formation and HI structural parameters. We quantify the HI structure by the size of the HI relative to the optical disc and the average HI surface density measured using effective and isodensity radii. For galaxies resolved by >1.3 beams, we find that galaxies with higher stellar masses and stellar surface densities tend to have less extended HI discs and lower HI surface densities: the isodensity HI structural parameters show a weak negative dependence on stellar mass and stellar mass surface density. These trends strengthen when we limit our sample to galaxies resolved by >2 beams. We find that galaxies with higher HI surface densities and more extended HI discs tend to be more star forming: the isodensity HI structural parameters have stronger correlations with star formation. Normalising the HI disc size by the optical effective radius (instead of the isophotal radius) produces positive correlations with stellar masses and stellar surface densities and removes the correlations with star formation. This is due to the effective and isodensity HI radii increasing with mass at similar rates while, in the optical, the effective radius increases slower than the isophotal radius. Our results demonstrate that with WALLABY we can begin to bridge the gap between small galaxy samples with high spatial resolution HI data and large, statistical studies using spatially unresolved, single-dish data., 16 page, 5 figures, accepted for publication in PASA

We present a new image of a 26.5 square degree region in the Bo\"otes constellation obtained at 1.4 GHz using the Aperture Tile in Focus (Apertif) system on the Westerbork Synthesis Radio Telescope. We use a newly developed processing pipeline which includes direction-dependent self-calibration which provides a significant improvement of the quality of the images compared to those released as part of the Apertif first data release. For the Bo\"otes region, we mosaic 187 Apertif images and extract a source catalog. The mosaic image has an angular resolution of 27${\times}$11.5 arcseconds and a median background noise of 40 ${\mu}$Jy/beam. The catalog has 8994 sources and is complete down to the 0.3 mJy level. We combine the Apertif image with LOFAR images of the Bo\"otes field at 54 and 150 MHz to study spectral properties of the sources. We find a spectral flattening towards low flux density sources. Using the spectral index limits from Apertif non-detections we derive that up to 9 percent of the sources have ultra-steep spectra with a slope steeper than -1.2. Steepening of the spectral index with increasing redshift is also seen in the data showing a different dependency for the low-frequency spectral index and the high frequency one. This can be explained by a population of sources having concave radio spectra with a turnover frequency around the LOFAR band. Additionally, we discuss cases of individual extended sources with an interesting resolved spectral structure. With the improved pipeline, we aim to continue processing data from the Apertif wide-area surveys and release the improved 1.4 GHz images of several famous fields., Comment: 13 pages, 9 figures; to be published in A&A

Context: To study the effects of environment on galaxies we use HI observations of galaxies in and around the cluster A2626. The cluster can effectively be divided in three different environments: the cluster itself, a group environment in the periphery of the cluster (we call it the Swarm) and substructure in the cluster itself. We use these to study the dependence of galaxy properties on environment. Aims: We have explored the relationship between HI deficiency, HI morphology, and star formation deficiency for the galaxies in and around the A2626 galaxy cluster to investigate the environmental effects on those properties. Methods: To quantify asymmetries of the outer HI disc of a galaxy, we used 1) three visual classes based on the outermost reliable HI contour (settled, disturbed, unsettled HI discs), 2) the offset between the HI centre and the optical centre of a galaxy, and 3) the modified asymmetry parameter Amod as defined by Lelli et al. (2014). Results: The HI deficiency of a galaxy is strongly correlated with the projected distance from the centre of A2626. Furthermore, substructure galaxies tend to be more asymmetric than the isolated galaxies in A2626, plausibly because of more efficient tidal interactions within substructures than outside substructures. Moreover, asymmetric, offset, and smaller HI discs are not necessarily the result of the cluster environment, as they are also observed in substructures in A2626 and in the Swarm. This signifies that "pre-processing" of the HI discs of galaxies in groups or substructures plays an important role, together with the "processing" in the cluster environment. Finally, the galaxies in all three environments have slightly lower star-formation rates (SFRs) than the typical SFR for normal galaxies as manifested by their offset from the star formation main sequence, implying effective gas removal mechanisms in all three environments., 19 pages, 12 figures

Open Access article, published by EDP Sciences, under the terms of the Creative Commons Attribution License (https://creativecommons.org/licenses/by/4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited., Galaxy mergers have been observed to trigger nuclear activity by feeding gas to the central supermassive black hole. One such class of objects are Ultra Luminous InfraRed Galaxies (ULIRGs), which are mostly late stage major mergers of gas-rich galaxies. Recently, large-scale (∼100 kpc) radio continuum emission has been detected in a select number of ULIRGs, all of which also harbour powerful Active Galactic Nuclei (AGN). This hints at the presence of large-scale radio emission being evidence for nuclear activity. Exploring the origin of this radio emission and its link to nuclear activity requires high sensitivity multi-frequency data. We present such an analysis of the ULIRG Mrk 273. Using the International LOFAR telescope (ILT), we detected spectacular large-scale arcs in this system. This detection includes, for the first time, a giant ∼190 kpc arc in the north. We propose these arcs are fuelled by a low power radio AGN triggered by the merger. We also identified a bright ∼45 kpc radio ridge, which is likely related to the ionised gas nebula in that region. We combined this with high sensitivity data from APERture Tile In Focus (Apertif) and archival data from the Very Large Array (VLA) to explore the spectral properties. The ILT simultaneously allowed us to probe the nucleus at a resolution of ∼0.3″, where we detected three components, and, for the first time, diffuse emission around these components. Combining this with archival high frequency VLA images of the nucleus allowed us to detect absorption in one component, and a steep spectrum radio AGN in another. We then extrapolate from this case study to the importance of investigating the presence of radio emission in more ULIRGs and what it can tell us about the link between mergers and the presence of radio activity. © P. Kukreti et al. 2022., LOFAR, the Low Frequency Array designed and constructed by ASTRON, has facilities in several countries, that are owned by various parties (each with their own funding sources), and that are collectively operated by the International LOFAR Telescope (ILT) foundation under a joint scientific policy. This work makes use of data from the Apertif system installed at the Westerbork Synthesis Radio Telescope owned by ASTRON. ASTRON, the Netherlands Institute for Radio Astronomy, is an institute of the Dutch Science Organisation (De Nederlandse Organisatie voor Wetenschappelijk Onderzoek, NWO). This work was supported by the Medical Research Council [MR/T042842/1]. CT acknowledges support from STFC. AD acknowledges support by the BMBF Verbundforschung under the grant 05A20STA. RJvW acknowledges support from the ERC Starting Grant ClusterWeb 804208. FdG acknowledges support from the Deutsche Forschungsgemeinschaft under Germany’s Excellence Strategy – EXC 2121 “Quantum Universe” – 390833306. EAKA is supported by the WISE research programme, which is financed by the Dutch Research Council (NWO). JvL acknowledges funding from Vici research programme ‘ARGO’ with project number 639.043.815, financed by the Dutch Research Council (NWO). LCO acknowledges funding from the European Research Council under the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement No. 617199. DV acknowledges support from the Netherlands eScience Center (NLeSC) under grant ASDI.15.406. JMvdH acknowledges funding from the Europeaní Research Council under the European Union’s Seventh Framework Programme (FP/2007-2013)/ERC Grant Agreement No. 291531 (‘HIStoryNU’). The Jülich LOFAR Long Term Archive and the German LOFAR network are both coordinated and operated by the Jülich Supercomputing Centre (JSC), and computing resources on the supercomputer JUWELS at JSC were provided by the Gauss Centre for Supercomputing e.V. (grant CHTB00) through the John von Neumann Institute for Computing (NIC). KMH acknowledges funding from the State Agency for Research of the Spanish Ministry of Science, Innovation and Universities through the “Center of Excellence Severo Ochoa” awarded to the Instituto de Astrofísica de Andalucía (SEV-2017-0709); from grant RTI2018-096228-B-C31 (Ministry of Science, Innovation and Universities/State Agency for Research/European Regional Development Funds, European Union); and from the coordination of the participation in SKA-SPAIN, funded by the Ministry of Science and innovation (MICIN).

Fast radio bursts (FRBs) are extragalactic radio transients of extraordinary luminosity. Studying the diverse temporal and spectral behaviour recently observed in a number of FRBs may help determine the nature of the entire class. For example, a fast spinning or highly magnetised neutron star might generate the rotation-powered acceleration required to explain the bright emission. Periodic, sub-second components, suggesting such rotation, were recently reported in one FRB, and potentially in two more. Here we report the discovery of FRB 20201020A with Apertif, an FRB showing five components regularly spaced by 0.415 ms. This sub-millisecond structure in FRB 20201020A carries important clues about the progenitor of this FRB specifically, and potentially about that of FRBs in general. We thus contrast its features to the predictions of the main FRB source models. We perform a timing analysis of the FRB 20201020A components to determine the significance of the periodicity. We compare these against the timing properties of the previously reported CHIME FRBs with sub-second quasi-periodic components, and against two Apertif bursts from repeating FRB 20180916B that show complex time-frequency structure. We find the periodicity of FRB 20201020A to be marginally significant at 2.5$\sigma$. Its repeating subcomponents cannot be explained as a pulsar rotation since the required spin rate of over 2 kHz exceeds the limits set by typical neutron star equations of state and observations. The fast periodicity is also in conflict with a compact object merger scenario. These quasi-periodic components could, however, be caused by equidistant emitting regions in the magnetosphere of a magnetar. The sub-millisecond spacing of the components in FRB 20201020A, the smallest observed so far in a one-off FRB, may rule out both neutron-star rotation and binary mergers as the direct source of quasi-periodic FRBs., Comment: 13 pages, 6 figures, 3 tables, supplementary material. Submitted to A&A

The Life-Long Learning (LLL) programme in Clinical Nutrition and Metabolism is an innovative and effective educational programme for medical doctors and health specialists offering online training and live courses, using a variety of modern training methodologies and resources.

We describe the APERture Tile In Focus (Apertif) system, a phased array feed (PAF) upgrade of the Westerbork Synthesis Radio Telescope which has transformed this telescope into a high-sensitivity, wide field-of-view L-band imaging and transient survey instrument. Using novel PAF technology, up to 40 partially overlapping beams can be formed on the sky simultaneously, significantly increasing the survey speed of the telescope. With this upgraded instrument, an imaging survey covering an area of 2300 deg2 is being performed which will deliver both continuum and spectral line data sets, of which the first data has been publicly released. In addition, a time domain transient and pulsar survey covering 15,000 deg2 is in progress. An overview of the Apertif science drivers, hardware and software of the upgraded telescope is presented, along with its key performance characteristics., 29 pages, 42 figures, accepted for publication by A&A

OBJECTIVES: The main aim of this study was to determine the impact on clinical practice of the first European Society of Gastroenterology, Hepatology, and Nutrition (ESPGHAN) position paper on the diagnosis and management of nutritional and gastrointestinal problems in children with neurological impairment (NI). METHODS: In this pilot-study, a web-based questionnaire was distributed between November, 2019 and June, 2020, amongst ESPGHAN members using the ESPGHAN newsletter. Fifteen questions covered the most relevant aspects on nutritional management and gastrointestinal issues of children with NI. A descriptive analysis of responses was performed. RESULTS: A total of 150 health professionals from 23 countries responded to the survey. A considerable variation in clinical practice concerning many aspects of nutritional and gastrointestinal management of children with NI was observed. The most frequently used method for diagnosing oropharyngeal dysfunction was the direct observation of meals with or without the use of standardised scores (n = 103). Anthropometric measurements were the most commonly used tools for assessing nutritional status (n = 111). The best treatment for gastroesophageal reflux disease (GERD) was considered to be proton pump inhibitor therapy by most (n = 116) participants. Regarding tube feeding, nearly all respondents (n = 114) agreed that gastrostomy is the best enteral access to be used for long-term enteral feeding. Fundoplication was indicated at the time of gastrostomy placement especially in case of uncontrolled GERD. CONCLUSIONS: More studies are required to address open questions on adequate management of children with NI. Identifying knowledge gaps paves the way for developing updated recommendations and improving patient care. Copyright © 2020 by European Society for Pediatric Gastroenterology, Hepatology, and Nutrition and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition.

Apertif is a new phased-array feed for the Westerbork Synthesis Radio Telescope (WSRT), greatly increasing its field of view and turning it into a natural survey instrument. In July 2019, the Apertif legacy surveys commenced; these are a time-domain survey and a two-tiered imaging survey, with a shallow and medium-deep component. The time-domain survey searches for new (millisecond) pulsars and fast radio bursts (FRBs). The imaging surveys provide neutral hydrogen (HI), radio continuum and polarization data products. With a bandwidth of 300 MHz, Apertif can detect HI out to a redshift of 0.26. The key science goals to be accomplished by Apertif include localization of FRBs (including real-time public alerts), the role of environment and interaction on galaxy properties and gas removal, finding the smallest galaxies, connecting cold gas to AGN, understanding the faint radio population, and studying magnetic fields in galaxies. After a proprietary period, survey data products will be publicly available through the Apertif Long Term Archive (ALTA, https://alta.astron.nl). I will review the progress of the surveys and present the first results from the Apertif surveys, including highlighting the currently available public data.

What is the road map for a change leader transforming a business from traditional manufacturing into a digital company? Easier said than done. Here we provide contextual concerns and identify possible steps, using a framework which has proved to be successful in many businesses. It is widely agreed that there is a need to continually transform any business as costs are always under pressure, and one way to minimize these costs is to look for technological answers. There is always risk in the transformation, in making the most appropriate investments in leaders, machines, and tools. Next to the costs of these assets is the need to keep your customers buying from you-whilst their expectations are shifting. They expect substantially more value from what they purchase, and a flawless customer experience. This is the new challenge for strategic leadership, and it is unlikely to stop here.

BACKGROUND: Most patients with cystic fibrosis (CF) suffer from pancreatic insufficiency, leading to fat malabsorption, malnutrition and abdominal discomfort. Until recently, no specific tool was available for assessing gastro-intestinal related quality of life (GI QOL) in patients with CF. As the Horizon2020 project MyCyFAPP aims to improve GI QOL by using a newly designed mobile application, a sensitive and reliable outcome measure was needed. We aimed to study the applicability of the existing child-specific Pediatric Quality of Life Inventory, Gastrointestinal Symptoms Scales and Module (PedsQL GI) in children with CF. METHODS: A multicenter, prospective observational study was performed in 6 European centers to validate the PedsQL GI in children with CF during 3 months. RESULTS: In total, 248 children and their parents were included. Within-patient variability of PedsQL GI was low (24.11), and there was reasonable agreement between children and parents (ICC 0.681). Nine of 14 subscales were informative (no ceiling effect). The PedsQL GI and the median scores for 4 subscales were significantly lower in patients compared to healthy controls. Positive associations were found between PedsQL GI and age (OR = 1.044, p = 0.004) and between PedsQL GI and BMI z-score (OR = 1.127, p = 0.036). PedsQL GI correlated with most CFQ-R subscales (r 0.268 to 0.623) and with a Visual Analogue Scale (r = 0.20). CONCLUSIONS: PedsQL GI is a valid and applicable instrument to assess GI QOL in children with CF. Future research efforts should examine the responsiveness of the CF PedsQL GI to change in the context of clinical interventions and trials. ispartof: PLOS ONE vol:14 issue:12 ispartof: location:United States status: published

Objective: To ascertain the clinical and genetic factors contributing to carbamazepine- and oxcarbazepine-induced hyponatremia (COIH), and to carbamazepine (CBZ) metabolism, in a retrospectively collected, cross-sectional cohort of people with epilepsy. Methods: We collected data on serum sodium levels and antiepileptic drug levels in people with epilepsy attending a tertiary epilepsy center while on treatment with CBZ or OXC. We defined hyponatremia as Na+ ≤134 mEq/L. We estimated the CBZ metabolic ratio defined as the log transformation of the ratio of metabolite CBZ-diol to unchanged drug precursor substrate as measured in serum. Results: Clinical and genetic data relating to carbamazepine and oxcarbazepine trials were collected in 1141 patients. We did not observe any genome-wide significant associations with sodium level in a linear trend or hyponatremia as a dichotomous trait. Age, sex, number of comedications, phenytoin use, phenobarbital use, and sodium valproate use were significant predictors of CBZ metabolic ratio. No genome-wide significant associations with CBZ metabolic ratio were found. Significance: Although we did not detect a genetic predictor of hyponatremia or CBZ metabolism in our cohort, our findings suggest that the determinants of CBZ metabolism are multifactorial., SCOPUS: ar.j, info:eu-repo/semantics/published

Objectives: Jejunal tube feeding (JTF) is increasingly becoming the standard of care for children in whom gastric tube feeding is insufficient to achieve caloric needs. Given a lack of a systematic approach to the care of JTF in paediatric patients, the aim of this position paper is to provide expert guidance regarding the indications for its use and practical considerations to optimize its utility and safety. Methods: A group of members of the Gastroenterology and Nutrition Committees of the European Society of Paediatric Gastroenterology Hepatology and Nutrition and of invited experts in the field was formed in September 2016 to produce this clinical guide. Seventeen clinical questions treating indications and contraindications, investigations before placement, techniques of placement, suitable feeds and feeding regimen, weaning from JTF, complications, long-term care, and ethical considerations were addressed. A systematic literature search was performed from 1982 to November 2018 using PubMed, the MEDLINE, and Cochrane Database of Systematic Reviews. Grading of Recommendations, Assessment, Development, and Evaluation was applied to evaluate the outcomes. During a consensus meeting, all recommendations were discussed and finalized. In the absence of evidence from randomized controlled trials, recommendations reflect the expert opinion of the authors. Results: A total of 33 recommendations were voted on using the nominal voting technique. Conclusions: JTF is a safe and effective means of enteral feeding when gastric feeding is insufficient to meet caloric needs or is not possible. The decision to place a jejunal tube has to be made by close cooperation of a multidisciplinary team providing active follow-up and care. © ESPGHAN and NASPGHAN. All rights reserved.

We have carried out a blind H i survey using the Westerbork Synthesis Radio Telescope to make an inventory of objects with small H i masses (between 106 and 108 M⊙) and to constrain the low-mass end of the H i mass function. The survey has been conducted in a part of the volume containing the nearby Canes Venatici groups of galaxies. The surveyed region covers an area on the sky of about 86 deg2 and a range in velocity from about −450 to about 1330 km s−1. We find 70 sources in the survey by applying an automated searching algorithm. Two of the detections have not been catalogued previously, but they can be assigned an optical counterpart, based on visual inspection of the second-generation Digital Sky Survey images. Only one of the H i detections is without an optical counterpart. This object is detected in the vicinity of NGC 4822, and it has been already detected in previous H i studies. 19 of the objects have been detected for the first time in the 21-cm emission line in this survey. The distribution of the H i properties of our detections confirms our ability to find low-mass objects. 86 per cent of the detections have profile widths less than 130 km s−1, and they can be considered dwarf galaxy candidates. The H i fluxes measured imply that this survey goes about 10 times deeper than any previous blind H i survey. The H i mass function and the optical properties of the detected sources will be discussed in future papers

Objectives: Feeding difficulties are frequent in children with neurological impairments and can be associated with undernutrition, growth failure, micronutrients deficiencies, osteopenia, and nutritional comorbidities. Gastrointestinal problems including gastroesophageal reflux disease, constipation, and dysphagia are also frequent in this population and affect quality of life and nutritional status. There is currently a lack of a systematic approach to the care of these patients. With this report, European Society of Gastroenterology, Hepatology and Nutrition aims to develop uniform guidelines for the management of the gastroenterological and nutritional problems in children with neurological impairment. Methods: Thirty-one clinical questions addressing the diagnosis, treatment, and prognosis of common gastrointestinal and nutritional problems in neurological impaired children were formulated. Questions aimed to assess the nutritional management including nutritional status, identifying undernutrition, monitoring nutritional status, and defining nutritional requirements; to classify gastrointestinal issues including oropharyngeal dysfunctions, motor and sensory function, gastroesophageal reflux disease, and constipation; to evaluate the indications for nutritional rehabilitation including enteral feeding and percutaneous gastrostomy/jejunostomy; to define indications for surgical interventions (eg, Nissen Fundoplication, esophagogastric disconnection); and finally to consider ethical issues related to digestive and nutritional problems in the severely neurologically impaired children. A systematic literature search was performed from 1980 to October 2015 using MEDLINE. The approach of the Grading of Recommendations Assessment, Development, and Evaluation was applied to evaluate the outcomes. During 2 consensus meetings, all recommendations were discussed and finalized. The group members voted on each recommendation using the nominal voting technique. Expert opinion was applied to support the recommendations where no randomized controlled trials were available. Copyright © 2017 by European Society for Pediatric Gastroenterology, Hepatology, and Nutrition and North American Society for Pediatric Gastroenterology, Hepatology, and Nutrition.

Upcoming HI surveys will deliver large datasets, and automated processing using the full 3-D information (two positional dimensions and one spectral dimension) to find and characterize HI objects is imperative. In this context, visualization is an essential tool for enabling qualitative and quantitative human control on an automated source finding and analysis pipeline. We discuss how Visual Analytics, the combination of automated data processing and human reasoning, creativity and intuition, supported by interactive visualization, enables flexible and fast interaction with the 3-D data, helping the astronomer to deal with the analysis of complex sources. 3-D visualization, coupled to modeling, provides additional capabilities helping the discovery and analysis of subtle structures in the 3-D domain. The requirements for a fully interactive visualization tool are: coupled 1-D/2-D/3-D visualization, quantitative and comparative capabilities, combined with supervised semi-automated analysis. Moreover, the source code must have the following characteristics for enabling collaborative work: open, modular, well documented, and well maintained. We review four state of-the-art, 3-D visualization packages assessing their capabilities and feasibility for use in the case of 3-D astronomical data., 19 pages, 6 figures, 2 tabular. Accepted for publication in Astronomy and Computing