802 results on '"Ruiter M"'
Search Results
2. First release of Apertif imaging survey data
- Author
-
Adams, Elizabeth A. K., Adebahr, B., de Blok, W. J. G., Denes, H., Hess, K. M., van der Hulst, J. M., Kutkin, A., Lucero, D. M., Morganti, R., Moss, V. A., Oosterloo, T. A., Orru, E., Schulz, R., van Amesfoort, A. S., Berger, A., Boersma, O. M., Bouwhuis, M., Brink, R. van den, van Cappellen, W. A., Connor, L., Coolen, A. H. W. M., Damstra, S., van Diepen, G. N. J., Dijkema, T. J., Ebbendorf, N., Grange, Y. G., de Goei, R., Gunst, A. W., Holties, H. A., Hut, B., Ivashina, M. V., Jozsa, G. I. G., Loose, G. M., van Leeuwen, J., Maan, Y., Mancini, M., Mika, A., Mulder, H., Norden, M. J., Offringa, A. R., Oostrum, L. C., Pastor-Marazuela, I., Pisano, D. J., Ponomareva, A. A., Romein, J. W., Ruiter, M, Schoenmakers, A. P., van der Schuur, D., Sluman, J. J., Smits, R., Stuurwold, K. J. C, Verstappen, J., Vilchez, N. P. E, Vohl, D., Wierenga, K. J., Wijnholds, S. J., Woestenburg, E. E. M., Zanting, A. W., and Ziemke, J.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
(Abridged) Apertif is a phased-array feed system for WSRT, providing forty instantaneous beams over 300 MHz of bandwidth. A dedicated survey program started on 1 July 2019, with the last observations taken on 28 February 2022. We describe the release of data products from the first year of survey operations, through 30 June 2020. We focus on defining quality control metrics for the processed data products. The Apertif imaging pipeline, Apercal, automatically produces non-primary beam corrected continuum images, polarization images and cubes, and uncleaned spectral line and dirty beam cubes for each beam of an Apertif imaging observation. For this release, processed data products are considered on a beam-by-beam basis within an observation. We validate the continuum images by using metrics that identify deviations from Gaussian noise in the residual images. If the continuum image passes validation, we release all processed data products for a given beam. We apply further validation to the polarization and line data products. We release all raw observational data from the first year of survey observations, for a total of 221 observations of 160 independent target fields, covering approximately one thousand square degrees of sky. Images and cubes are released on a per beam basis, and 3374 beams are released. The median noise in the continuum images is 41.4 uJy/bm, with a slightly lower median noise of 36.9 uJy/bm in the Stokes V polarization image. The median angular resolution is 11.6"/sin(Dec). The median noise for all line cubes, with a spectral resolution of 36.6 kHz, is 1.6 mJy/bm, corresponding to a 3-sigma HI column density sensitivity of 1.8 x 10^20 atoms cm^-2 over 20 km/s (for a median angular resolution of 24" x 15"). We also provide primary beam images for each individual Apertif compound beam. The data are made accessible using a Virtual Observatory interface., Comment: Accepted for publication in A&A, updated Figure 1
- Published
- 2022
- Full Text
- View/download PDF
3. The Apertif science verification campaign - Characteristics of polarised radio sources
- Author
-
Adebahr, B., Berger, A., Adams, E. A. K., Hess, K. M., de Blok, W. J. G., Dénes, H., Moss, V. A., Schulz, R., van der Hulst, J. M., Connor, L., Damstra, S., Hut, B., Ivashina, M. V., Loose, G. M., Maan, Y., Mika, A., Mulder, H., Norden, M. J., Oostrum, L. C., Orrú, E., Ruiter, M., Smits, R., van Cappellen, W. A., van Leeuwen, J., Vermaas, N. J., Vohl, D., and Ziemke, J.
- Subjects
Astrophysics - Astrophysics of Galaxies ,Astrophysics - Cosmology and Nongalactic Astrophysics ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
We analyse five early science datasets from the APERture Tile in Focus (Apertif) phased array feed system to verify the polarisation capabilities of Apertif in view of future larger data releases. We aim to characterise the source population of the polarised sky in the L-Band using polarised source information in combination with IR and optical data. We use automatic routines to generate full field-of-view Q- and U-cubes and perform RM-Synthesis, source finding, and cross-matching with published radio, optical, and IR data to generate polarised source catalogues. SED-fitting routines were used to determine photometric redshifts, star-formation rates, and galaxy masses. IR colour information was used to classify sources as AGN or star-forming-dominated and early- or late-type. We surveyed an area of 56deg$^2$ and detected 1357 polarised source components in 1170 sources. The fraction of polarised sources is 10.57% with a median fractional polarisation of 4.70$\pm$0.14%. We confirmed the reliability of the Apertif measurements by comparing them with polarised cross-identified NVSS sources. Average RMs of the individual fields lie within the error of the best Milky Way foreground measurements. All of our polarised sources were found to be dominated by AGN activity in the radio regime with most of them being radio-loud (79%) and of the FRII class (87%). The host galaxies of our polarised source sample are dominated by intermediate disc and star-forming disc galaxies. The contribution of star formation to the radio emission is on the order of a few percent for $\approx$10% of the polarised sources while for $\approx$90% it is completely dominated by the AGN. We do not see any change in fractional polarisation for different star-formation rates of the AGN host galaxies., Comment: 24 pages, 21 figures
- Published
- 2022
- Full Text
- View/download PDF
4. Apertif, Phased Array Feeds for the Westerbork Synthesis Radio Telescope
- Author
-
van Cappellen, W. A., Oosterloo, T. A., Verheijen, M. A. W., Adams, E. A. K., Adebahr, B., Braun, R., Hess, K. M., Holties, H., van der Hulst, J. M., Hut, B., Kooistra, E., van Leeuwen, J., Loose, G. M., Morganti, R., Moss, V. A., Orrú, E., Ruiter, M., Schoenmakers, A. P., Vermaas, N. J., Wijnholds, S. J., van Amesfoort, A. S., Arts, M. J., Attema, J. J., Bakker, L., Bassa, C. G., Bast, J. E., Benthem, P., Beukema, R., Blaauw, R., de Blok, W. J. G., Bouwhuis, M., Brink, R. H. van den, Connor, L., Coolen, A. H. W. M., Damstra, S., van Diepen, G. N. J., de Goei, R., Dénes, H., Drost, M., Ebbendorf, N., Frank, B. S., Gardenier, D. W., Gerbers, M., Grange, Y. G., Grit, T., Gunst, A. W., Gupta, N., Ivashina, M. V., Józsa, G. I. G., Janssen, G. H., Koster, A., Kruithof, G. H., Kuindersma, S. J., Kutkin, A., Lucero, D. M., Maan, Y., Maccagni, F. M., van der Marel, J., Mika, A., Morawietz, J., Mulder, H., Mulder, E., Norden, M. J., Offringa, A. R., Oostrum, L. C., Overeem, R. E., Paragi, Z., Pepping, H. J., Petroff, E., Pisano, D. J., Polatidis, A. G., Prasad, P., de Reijer, J. P. R., Romein, J. W., Schaap, J., Schoonderbeek, G. W., Schulz, R., van der Schuur, D., Sclocco, A., Sluman, J. J., Smits, R., Stappers, B. W., Straal, S. M., Stuurwold, K. J. C., Verstappen, J., Vohl, D., Wierenga, K. J., Woestenburg, E. E. M., Zanting, A. W., and Ziemke, J.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
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., Comment: 29 pages, 42 figures, accepted for publication by A&A
- Published
- 2021
- Full Text
- View/download PDF
5. Dual-frequency single-pulse study of PSR B0950+08
- Author
-
Bilous, A. V., Griessmeier, J. M., Pennucci, T., Wu, Z., Bondonneau, L., Kondratiev, V., van Leeuwen, J., Maan, Y., Connor, L., Oostrum, L. C., Petroff, E., Verbiest, J. P. W., Vohl, D., McKee, J. W., Shaifullah, G., Theureau, G., Ulyanov, O. M., Cecconi, B., Coolen, A. H., Corbel, S., Damstra, S., Denes, H., Girard, J. N., Hut, B., Ivashina, M., Konovalenko, O. O., Kutkin, A., Loose, G. M., Mulder, H., Ruiter, M., Smits, R., Tokarsky, P. L., Vermaas, N. J., Zakharenko, V. V., Zarka, P., and Ziemke, J.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena ,Astrophysics - Solar and Stellar Astrophysics - Abstract
PSR B0950+08 is a bright non-recycled pulsar whose single-pulse fluence variability is reportedly large. Based on observations at two widely separated frequencies, 55 MHz (NenuFAR) and 1.4 GHz (Westerbork Synthesis Radio Telescope), we review the properties of these single pulses. We conclude that they are more similar to ordinary pulses of radio emission than to a special kind of short and bright Giant Pulses, observed from only a handful of pulsars. We argue that temporal variation of properties of interstellar medium along the line of sight to this nearby pulsar, namely the fluctuating size of decorrelation bandwidth of diffractive scintillation makes important contribution to observed single-pulse fluence variability. We further present interesting structures in the low-frequency single-pulse spectra that resemble the "sad trombones" seen in Fast Radio Bursts (FRBs); although for PSR B0950+08 the upward frequency drift is also routinely present. We explain these spectral features with radius-to-frequency mapping, similar to the model developed by Wang et al. (2019) for FRBs. Finally, we speculate that microsecond-scale fluence variability of the general pulsar population remains poorly known, and that its further study may bring important clues about the nature of FRBs., Comment: Accepted by A&A. This version includes a number of minor corrections, including corrected FRB luminosities on the time-luminosity phase-space plot for radio pulses from neutron stars and repeating FRBs
- Published
- 2021
- Full Text
- View/download PDF
6. Sub-arcsecond imaging with the International LOFAR Telescope I. Foundational calibration strategy and pipeline
- Author
-
Morabito, L. K., Jackson, N. J., Mooney, S., Sweijen, F., Badole, S., Kukreti, P., Venkattu, D., Groeneveld, C., Kappes, A., Bonnassieux, E., Drabent, A., Iacobelli, M., Croston, J. H., Best, P. N., Bondi, M., Callingham, J. R., Conway, J. E., Deller, A. T., Hardcastle, M. J., McKean, J. P., Miley, G. K., Moldon, J., Röttgering, H. J. A., Tasse, C., Shimwell, T. W., van Weeren, R. J., Anderson, J. M., Asgekar, A., Avruch, I. M., van Bemmel, I. M., Bentum, M. J., Bonafede, A., Brouw, W. N., Butcher, H. R., Ciardi, B., Corstanje, A., Coolen, A., Damstra, S., de Gasperin, F., Duscha, S., Eislöffel, J., Engels, D., Falcke, H., Garrett, M. A., Griessmeier, J., Gunst, A. W., van Haarlem, M. P., Hoeft, M., van der Horst, A. J., Jütte, E., Kadler, M., Koopmans, L. V. E., Krankowski, A., Mann, G., Nelles, A., Oonk, J. B. R., Orru, E., Paas, H., Pandey, V. N., Pizzo, R. F., Pandey-Pommier, M., Reich, W., Rothkaehl, H., Ruiter, M., Schwarz, D. J., Shulevski, A., Soida, M., Tagger, M., Vocks, C., Wijers, R. A. M. J., Wijnholds, S. J., Wucknitz, O., Zarka, P., and Zucca, P.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - Astrophysics of Galaxies - Abstract
[abridged] The International LOFAR Telescope is an interferometer with stations spread across Europe. With baselines of up to ~2,000 km, LOFAR has the unique capability of achieving sub-arcsecond resolution at frequencies below 200 MHz, although this is technically and logistically challenging. Here we present a calibration strategy that builds on previous high-resolution work with LOFAR. We give an overview of the calibration strategy and discuss the special challenges inherent to enacting high-resolution imaging with LOFAR, and describe the pipeline, which is publicly available, in detail. We demonstrate the calibration strategy by using the pipeline on P205+55, a typical LOFAR Two-metre Sky Survey (LoTSS) pointing. We perform in-field delay calibration, solution referencing to other calibrators, self-calibration, and imaging of example directions of interest in the field. For this specific field and these ionospheric conditions, dispersive delay solutions can be transferred between calibrators up to ~1.5 degrees away, while phase solution transferral works well over 1 degree. We demonstrate a check of the astrometry and flux density scale. Imaging in 17 directions, the restoring beam is typically 0.3" x 0.2" although this varies slightly over the entire 5 square degree field of view. We achieve ~80 to 300 $\mu$Jy/bm image rms noise, which is dependent on the distance from the phase centre; typical values are ~90 $\mu$Jy/bm for the 8 hour observation with 48 MHz of bandwidth. Seventy percent of processed sources are detected, and from this we estimate that we should be able to image ~900 sources per LoTSS pointing. This equates to ~3 million sources in the northern sky, which LoTSS will entirely cover in the next several years. Future optimisation of the calibration strategy for efficient post-processing of LoTSS at high resolution (LoTSS-HR) makes this estimate a lower limit., Comment: Accepted to a special issue of A&A on sub-arcsecond imaging with LOFAR. 24 pages, 16 figures
- Published
- 2021
- Full Text
- View/download PDF
7. Sub-arcsecond imaging with the International LOFAR Telescope: II. Completion of the LOFAR Long-Baseline Calibrator Survey
- Author
-
Jackson, Neal, Badole, Shruti, Morgan, John, Chhetri, Rajan, Prusis, Kaspars, Nikolajevs, Atvars, Morabito, Leah, Brentjens, Michiel, Sweijen, Frits, Iacobelli, Marco, Orrù, Emanuela, Sluman, J., Blaauw, R., Mulder, H., van Dijk, P., Mooney, Sean, Deller, Adam, Moldon, Javier, Callingham, J. R., Harwood, Jeremy, Hardcastle, Martin, Heald, George, Drabent, Alexander, McKean, J. P., Asgekar, A., Avruch, I. M., Bentum, M. J., Bonafede, A., Brouw, W. N., Brüggen, M., Butcher, H. R., Ciardi, B., Coolen, A., Corstanje, A., Damstra, S., Duscha, S., Eislöffel, J., Falcke, H., Garrett, M., de Gasperin, F., Griessmeier, J. -M., Gunst, A. W., van Haarlem, M. P., Hoeft, M., van der Horst, A. J., Jütte, E., Koopmans, L. V. E., Krankowski, A., Maat, P., Mann, G., Miley, G. K., Nelles, A., Norden, M., Paas, M., Pandey, V. N., Pandey-Pommier, M., Pizzo, R. F., Reich, W., Rothkaehl, H., Rowlinson, A., Ruiter, M., Shulevski, A., Schwarz, D. J., Smirnov, O., Tagger, M., Vocks, C., van Weeren, R. J., Wijers, R., Wucknitz, O., Zarka, P., Zensus, J. A., and Zucca, P.
- Subjects
Astrophysics - Astrophysics of Galaxies ,Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
The Low-Frequency Array (LOFAR) Long-Baseline Calibrator Survey (LBCS) was conducted between 2014 and 2019 in order to obtain a set of suitable calibrators for the LOFAR array. In this paper we present the complete survey, building on the preliminary analysis published in 2016 which covered approximately half the survey area. The final catalogue consists of 30006 observations of 24713 sources in the northern sky, selected for a combination of high low-frequency radio flux density and flat spectral index using existing surveys (WENSS, NVSS, VLSS, and MSSS). Approximately one calibrator per square degree, suitable for calibration of $\geq$ 200 km baselines is identified by the detection of compact flux density, for declinations north of 30 degrees and away from the Galactic plane, with a considerably lower density south of this point due to relative difficulty in selecting flat-spectrum candidate sources in this area of the sky. Use of the VLBA calibrator list, together with statistical arguments by comparison with flux densities from lower-resolution catalogues, allow us to establish a rough flux density scale for the LBCS observations, so that LBCS statistics can be used to estimate compact flux densities on scales between 300 mas and 2 arcsec, for sources observed in the survey. The LBCS can be used to assess the structures of point sources in lower-resolution surveys, with significant reductions in the degree of coherence in these sources on scales between 2 arcsec and 300 mas. The LBCS survey sources show a greater incidence of compact flux density in quasars than in radio galaxies, consistent with unified schemes of radio sources. Comparison with samples of sources from interplanetary scintillation (IPS) studies with the Murchison Widefield Array (MWA) shows consistent patterns of detection of compact structure in sources observed both interferometrically with LOFAR and using IPS., Comment: Accepted to a special issue of A&A on sub-arcsecond imaging with LOFAR
- Published
- 2021
- Full Text
- View/download PDF
8. A search for radio emission from double-neutron star merger GW190425 using Apertif
- Author
-
Boersma, Olivér, van Leeuwen, Joeri, Adams, Elizabeth A. K., Adebahr, Björn, Kutkin, Alexander, Oosterloo, Tom, de Blok, W. J. G., Brink, R. van den, Coolen, A. H. W. M., Connor, L., Damstra, S., Dénes, H., Hess, K. M., van der Hulst, J. M., Hut, B., Ivashina, M., Loose, G. M., Lucero, D. M., Maan, Y., Mika, Á., Moss, V. A., Mulder, H., Oostrum, L. C., Ruiter, M., van der Schuur, D., Smits, R., Vermaas, N. J., Vohl, D., and Ziemke, J.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena - Abstract
Detection of the electromagnetic emission from coalescing binary neutron stars (BNS) is important for understanding the merger and afterglow. We present a search for a radio counterpart to the gravitational-wave source GW190425, a BNS merger, using Apertif on the Westerbork Synthesis Radio Telescope (WSRT). We observe a field of high probability in the associated localisation region for 3 epochs at 68, 90 and 109 days post merger. We identify all sources that exhibit flux variations consistent with the expected afterglow emission of GW190425. We also look for possible transients. These are sources which are only present in one epoch. In addition, we quantify our ability to search for radio afterglows in fourth and future observing runs of the gravitational-wave detector network using Monte Carlo simulations. We found 25 afterglow candidates based on their variability. None of these could be associated with a possible host galaxy at the luminosity distance of GW190425. We also found 55 transient afterglow candidates that were only detected in one epoch. All turned out to be image artefacts. In the fourth observing run, we predict that up to three afterglows will be detectable by Apertif. While we did not find a source related to the afterglow emission of GW190425, the search validates our methods for future searches of radio afterglows., Comment: 11 pages, 7 figures, accepted for publication
- Published
- 2021
- Full Text
- View/download PDF
9. Apertif view of the OH Megamaser IRAS 10597+5926: OH 18 cm satellite lines in wide-area HI surveys
- Author
-
Hess, Kelley M., Roberts, H., Dénes, H., Adebahr, B., Darling, J., Adams, E. A. K., de Blok, W. J. G., Kutkin, A., Lucero, D. M., Morganti, Raffaella, Moss, V. A., Oosterloo, T. A., Schulz, R., van der Hulst, J. M., Coolen, A. H. W. M., Damstra, S., Ivashina, M., Loose, G. Marcel, Maan, Yogesh, Mika, Á., Mulder, H., Norden, M. J., Oostrum, L. C., Ruiter, M., van Leeuwen, Joeri, Vermaas, N. J., Vohl, D., Wijnholds, S. J., and Ziemke, J.
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
We present the serendipitous detection of the two main OH maser lines at 1667 and 1665 MHz associated with IRAS 10597+5926 at z = 0.19612 in the untargeted Apertif Wide-area Extragalactic Survey (AWES), and the subsequent measurement of the OH 1612 MHz satellite line in the same source. With a total OH luminosity of log(L/L_Sun) = 3.90 +/- 0.03, IRAS 10597+5926 is the fourth brightest OH megamaser (OHM) known. We measure a lower limit for the 1667/1612 ratio of R_1612 > 45.9 which is the highest limiting ratio measured for the 1612 MHz OH satellite line to date. OH satellite line measurements provide a potentially valuable constraint by which to compare detailed models of OH maser pumping mechanisms. Optical imaging shows the galaxy is likely a late-stage merger. Based on published infrared and far ultraviolet fluxes, we find that the galaxy is an ultra luminous infrared galaxy (ULIRG) with log(L_TIR/L_Sun) = 12.24, undergoing a star burst with an estimated star formation rate of 179 +/- 40 M_Sun/yr. These host galaxy properties are consistent with the physical conditions responsible for very bright OHM emission. Finally, we provide an update on the predicted number of OH masers that may be found in AWES, and estimate the total number of OH masers that will be detected in each of the individual main and satellite OH 18 cm lines., Comment: 9 pages, 4 figures. Accepted for publication in A&A
- Published
- 2021
- Full Text
- View/download PDF
10. The best of both worlds: Combining LOFAR and Apertif to derive resolved radio spectral index images
- Author
-
Morganti, R., Oosterloo, T. A., Brienza, M., Jurlin, N., Prandoni, I., Orru', E., Shabala, S. S., Adams, E. A. K., Adebahr, B., Best, P. N., Coolen, A. H. W. M., Damstra, S., de Blok, W. J. G., de Gasperin, F., Denes, H., Hardcastle, M., Hess, K. M., Hut, B., Kondapally, R., Kutkin, A. M., Loose, G. M., Lucero, D. M., Maan, Y., Maccagni, F. M., Mingo, B., Moss, V. A., Mostert, R. I. J., Norden, M. J., Oostrum, L. C., Rottgering, H. J. A., Ruiter, M., Shimwell, T. W., Schulz, R., Vermaas, N. J., Vohl, D., van der Hulst, J. M., van Diepen, G. M., van Leeuwen, J., and Ziemke, J.
- Subjects
Astrophysics - Astrophysics of Galaxies - Abstract
Supermassive black holes at the centres of galaxies can cycle through periods of activity and quiescence. Characterising the duty cycle of active galactic nuclei is crucial for understanding the impact of the energy they release on the host galaxy. For radio AGN, this can be done by identifying dying (remnant) and restarted radio galaxies from their radio spectral properties. Using the combination of images at 1400 MHz produced by Apertif, the new phased-array feed receiver installed on the Westerbork Synthesis Radio Telescope, and images at 150 MHz provided by LOFAR, we have derived resolved spectral index images (at a resolution of ~15 arcsec) for all the sources within ~6 deg^2 area of the Lockman Hole region. We were able to select 15 extended radio sources with emission (partly or entirely) characterised by extremely steep spectral indices (steeper than 1.2). These objects represent radio sources in the remnant or the restarted phases of their life cycle. Our findings suggest this cycle to be relatively fast. They also show a variety of properties relevant for modelling the evolution of radio galaxies. For example, the restarted activity can occur while the remnant structure from a previous phase of activity is still visible. This provides constraints on the duration of the 'off' (dying) phase. In extended remnants with ultra-steep spectra at low frequencies, the activity likely stopped a few hundred megayears ago, and they correspond to the older tail of the age distribution of radio galaxies, in agreement with simulations of radio source evolution. We find remnant radio sources with a variety of structures (from double-lobed to amorphous), suggesting different types of progenitors. The present work sets the stage for exploiting low-frequency spectral index studies of extended sources by taking advantage of the large areas common to the LOFAR and the Apertif surveys., Comment: Accepted for publication in A&A. This paper is part of the 1st data release of the LoTSS Deep Fields. 17 pages, 10 figures
- Published
- 2020
- Full Text
- View/download PDF
11. Extreme intra-hour variability of the radio source J1402+5347 discovered with Apertif
- Author
-
Oosterloo, T. A., Vedantham, H. K., Kutkin, A. M., Adams, E. A. K., Adebahr, B., Coolen, A. H. W. M., Damstra, S., de Blok, W. J. G., De'nes, H., Hess, K. M., Hut, B., Loose, G. M., Lucero, D. M., Maan, Y., Morganti, R., Moss, V. A., Mulder, H., Norden, M. J., Offringa, A. R., Oostrum, L. C., Orru`, E., Ruiter, M., Schulz, R., Brink, R. H. van den, van der Hulst, J. M., van Leeuwen, J., Vermaas, N. J., Vohl, D., Wijnholds, S. J., and Ziemke, J.
- Subjects
Astrophysics - Astrophysics of Galaxies ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
The propagation of radio waves from distant compact radio sources through turbulent interstellar plasma in our Galaxy causes these sources to twinkle, a phenomenon called interstellar scintillation. Such scintillations are a unique probe of the micro-arcsecond structure of radio sources as well as of the sub-AU-scale structure of the Galactic interstellar medium. Weak scintillations (i.e. an intensity modulation of a few percent) on timescales of a few days or longer are commonly seen at centimetre wavelengths and are thought to result from the line-of-sight integrated turbulence in the interstellar plasma of the Milky Way. So far, only three sources were known that show more extreme variations, with modulations at the level of some dozen percent on timescales shorter than an hour. This requires propagation through nearby (d <~10 pc) anomalously dense (n_e ~10^2 cm^-3) plasma clouds. Here we report the discovery with Apertif of a source (J1402+5347) showing extreme (~50%) and rapid variations on a timescale of just 6.5 minutes in the decimetre band (1.4 GHz). The spatial scintillation pattern is highly anisotropic, with a semi-minor axis of about 20,000 km. The canonical theory of refractive scintillation constrains the scattering plasma to be within the Oort cloud. The sightline to J1402+5347, however, passes unusually close to the B3 star Alkaid (eta UMa) at a distance of 32 pc. If the scintillations are associated with Alkaid, then the angular size of J1402+5347 along the minor axis of the scintels must be smaller than ~10 micro arcsec yielding an apparent brightness temperature for an isotropic source of >~ 10^ 14K. }, Comment: Accepted for Astronomy and Astrophysics Letters
- Published
- 2020
- Full Text
- View/download PDF
12. A bright, high rotation-measure FRB that skewers the M33 halo
- Author
-
Connor, Liam, van Leeuwen, Joeri, Oostrum, L. C., Petroff, E., Maan, Yogesh, Adams, E. A. K., Attema, J. J., Bast, J. E., Boersma, O. M., Dénes, H., Gardenier, D. W., Hargreaves, J. E., Kooistra, E., Pastor-Marazuela, I., Schulz, R., Sclocco, A., Smits, R., Straal, S. M., van der Schuur, D., Vohl, Dany, Adebahr, B., de Blok, W. J. G., van Cappellen, W. A., Coolen, A. H. W. M., Damstra, S., van Diepen, G. N. J., Frank, B. S., Hess, K. M., Hut, B., Loose, G. Marcel, Lucero, D. M., Mika, Á., Moss, V. A., Mulder, H., Oosterloo, T. A., Ruiter, M., Vedantham, H., Vermaas, N. J., Wijnholds, S. J., and Ziemke, J.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena - Abstract
We report the detection of a bright fast radio burst, FRB\,191108, with Apertif on the Westerbork Synthesis Radio Telescope (WSRT). The interferometer allows us to localise the FRB to a narrow $5\arcsec\times7\arcmin$ ellipse by employing both multibeam information within the Apertif phased-array feed (PAF) beam pattern, and across different tied-array beams. The resulting sight line passes close to Local Group galaxy M33, with an impact parameter of only 18\,kpc with respect to the core. It also traverses the much larger circumgalactic medium of M31, the Andromeda Galaxy. We find that the shared plasma of the Local Group galaxies could contribute $\sim$10\% of its dispersion measure of 588\,pc\,cm$^{-3}$. FRB\,191108 has a Faraday rotation measure of +474\,$\pm\,3$\,rad\,m$^{-2}$, which is too large to be explained by either the Milky Way or the intergalactic medium. Based on the more moderate RMs of other extragalactic sources that traverse the halo of M33, we conclude that the dense magnetised plasma resides in the host galaxy. The FRB exhibits frequency structure on two scales, one that is consistent with quenched Galactic scintillation and broader spectral structure with $\Delta\nu\approx40$\,MHz. If the latter is due to scattering in the shared M33/M31 CGM, our results constrain the Local Group plasma environment. We found no accompanying persistent radio sources in the Apertif imaging survey data.
- Published
- 2020
- Full Text
- View/download PDF
13. Repeating fast radio bursts with WSRT/Apertif
- Author
-
Oostrum, L. C., Maan, Y., van Leeuwen, J., Connor, L., Petroff, E., Attema, J. J., Bast, J. E., Gardenier, D. W., Hargreaves, J. E., Kooistra, E., van der Schuur, D., Sclocco, A., Smits, R., Straal, S. M., ter Veen, S., Vohl, D., Adams, E. A. K., Adebahr, B., de Blok, W. J. G., Brink, R. H. van den, van Cappellen, W. A., Coolen, A. H. W. M., Damstra, S., van Diepen, G. N. J., Frank, B. S., Hess, K. M., van der Hulst, J. M., Hut, B., Ivashina, M. V., Loose, G. M., Lucero, D. M., Mika, Á., Morganti, R. H., Moss, V. A., Mulder, H., Norden, M. J., Oosterloo, T. A., Orrú, E., de Reijer, J. P. R., Ruiter, M., Vermaas, N. J., Wijnholds, S. J., and Ziemke, J.
- Subjects
Astrophysics - High Energy Astrophysical Phenomena - Abstract
Repeating fast radio bursts (FRBs) present excellent opportunities to identify FRB progenitors and host environments, as well as decipher the underlying emission mechanism. Detailed studies of repeating FRBs might also hold clues to the origin of FRBs as a population. We aim to detect the first two repeating FRBs: FRB 121102 (R1) and FRB 180814.J0422+73 (R2), and characterise their repeat statistics. We also want to significantly improve the sky localisation of R2. We use the Westerbork Synthesis Radio Telescope to conduct extensive follow-up of these two repeating FRBs. The new phased-array feed system, Apertif, allows covering the entire sky position uncertainty of R2 with fine spatial resolution in one pointing. We characterise the energy distribution and the clustering of detected R1 bursts. We detected 30 bursts from R1. Our measurements indicate a dispersion measure of 563.5(2) pc cm$^{-3}$, suggesting a significant increase in DM over the past few years. We place an upper limit of 8% on the linear polarisation fraction of the brightest burst. We did not detect any bursts from R2. A single power-law might not fit the R1 burst energy distribution across the full energy range or widely separated detections. Our observations provide improved constraints on the clustering of R1 bursts. Our stringent upper limits on the linear polarisation fraction imply a significant depolarisation, either intrinsic to the emission mechanism or caused by the intervening medium, at 1400 MHz that is not observed at higher frequencies. The non-detection of any bursts from R2 implies either a highly clustered nature of the bursts, a steep spectral index, or a combination of both. Alternatively, R2 has turned off completely, either permanently or for an extended period of time., Comment: 11 pages, 7 figures, submitted to A&A
- Published
- 2019
- Full Text
- View/download PDF
14. The AI ethics maturity model: a holistic approach to advancing ethical data science in organizations
- Author
-
Krijger, J., Thuis, T., de Ruiter, M., Ligthart, E., and Broekman, I.
- Published
- 2022
- Full Text
- View/download PDF
15. Effect of physical exercise on cognitive function after chemotherapy in patients with breast cancer: a randomized controlled trial (PAM study)
- Author
-
Koevoets, E. W., Schagen, S. B., de Ruiter, M. B., Geerlings, M. I., Witlox, L., van der Wall, E., Stuiver, M. M., Sonke, G. S., Velthuis, M. J., Jobsen, J. J., Menke-Pluijmers, M. B. E., Göker, E., van der Pol, C. C., Bos, M. E. M. M., Tick, L. W., van Holsteijn, N. A., van der Palen, J., May, A. M., and Monninkhof, E. M.
- Published
- 2022
- Full Text
- View/download PDF
16. Analysis of a Small LOFAR Low-Band Test Array Using a Sky Map, Simulated Embedded Element Patterns and Measured LNA-Impedances
- Author
-
Arts, M. J., primary, Ruiter, M., additional, Kruger, P., additional, Prinsloo, D., additional, Bentum, M.J., additional, and Smolders, A. B., additional
- Published
- 2024
- Full Text
- View/download PDF
17. Good Days and Bad Days: Measuring Health-Related Quality of Life in People With Epilepsy
- Author
-
Enders-Slegers, M.J., de Ruiter, M., Corro-Ramos, I., le Cessie, S., Mourits, J., van den Hurk-van Schadewijk, J., de Wit, U., Marell, H., Verhoeven, H., Wester, Valérie, de Groot, Saskia, Versteegh, Matthijs, Kanters, Tim, Wagner, Louis, Ardesch, Jacqueline, Brouwer, Werner, and van Exel, Job
- Published
- 2021
- Full Text
- View/download PDF
18. Effect of physical exercise on brain perfusion in chemotherapy-treated breast cancer patients: a randomized controlled trial (PAM study)
- Author
-
Koevoets, E. W., (0000-0002-3201-6002) Petr, J., Monninkhof, E. M., Geerlings, M. I., Witlox, L., Wall, E., Stuiver, M. M., Sonke, G. S., Velthuis, M. J., Jobsen, J. J., Palen, J., Jmm Mutsaerts, H., Ruiter, M. B., May, A. M., Schagen, S. B., Koevoets, E. W., (0000-0002-3201-6002) Petr, J., Monninkhof, E. M., Geerlings, M. I., Witlox, L., Wall, E., Stuiver, M. M., Sonke, G. S., Velthuis, M. J., Jobsen, J. J., Palen, J., Jmm Mutsaerts, H., Ruiter, M. B., May, A. M., and Schagen, S. B.
- Abstract
BACKGROUND Breast cancer patients may experience cognitive difficulties after chemotherapy. PURPOSE To investigate whether an exercise intervention can affect cerebral blood flow (CBF) in breast cancer patients and if CBF changes relate to memory function. STUDY TYPE Prospective. POPULATION Chemotherapy-treated breast cancer patients with cognitive problems, and with relatively low physical activity levels were randomized to an exercise intervention (n=91) or control group (n=90). FIELDSTRENGTH/SEQUENCE A 3-T arterial spin labeling CBF scan was performed. ASSESSMENT The 6-month intervention consisted of (supervised) aerobic and strength training, 4x1 hour/week. Measurements at baseline (2-4 years post-diagnosis) and after six months included the arterial spin labeling CBF scan, from which we calculated gray matter CBF in the whole brain, hippocampus, anterior cingulate cortex, and posterior cingulate cortex. Furthermore, we measured physical fitness and memory functioning. STATISTICAL TESTS Multiple regression analyses with a two-sided alpha of 0.05 for all analyses. RESULTS We observed significant improvement in physical fitness (VO2peak) in the intervention group (n=53) compared to controls (n=51, B1.47, 95%CI:0.44; 2.50), nevertheless no intervention effects on CBF were found (e.g. whole brain: B0.98, 95%CI:-2.38; 4.34). Highly fatigued patients showed larger, but not significant, treatment effects. Additionally, change in physical fitness, from baseline to post-intervention, was positively associated with changes in CBF (e.g., whole brain: B0.75, 95%CI:0.07; 1.43). However, we observed no relation between CBF changes and change in memory performance. DATA CONCLUSION The exercise intervention did not affect CBF of cognitively affected breast cancer patients. However, a change in physical fitness was related to a change in CBF, but a change in CBF was not associated with memory functioning.
- Published
- 2024
19. Uncovering the dynamics of multi-sector impacts of hydrological extremes: A methods overview
- Author
-
de Brito, Mariana Madruga, Sodoge, Jan, Fekete, A., Hagenlocher, M., Koks, E., Kuhlicke, Christian, Messori, G., de Ruiter, M., Schweizer, P.-J., Ward, P.J., de Brito, Mariana Madruga, Sodoge, Jan, Fekete, A., Hagenlocher, M., Koks, E., Kuhlicke, Christian, Messori, G., de Ruiter, M., Schweizer, P.-J., and Ward, P.J.
- Abstract
Hydrological extremes, such as droughts and floods, can trigger a complex web of compound and cascading impacts (CCI) due to interdependencies between coupled natural and social systems. However, current decision-making processes typically only consider one impact and disaster event at a time, ignoring causal chains, feedback loops, and conditional dependencies between impacts. Analyses capturing these complex patterns across space and time are thus needed to inform effective adaptation planning. This perspective paper aims to bridge this critical gap by presenting methods for assessing the dynamics of the multi-sector CCI of hydrological extremes. We discuss existing challenges, good practices, and potential ways forward. Rather than pursuing a single methodological approach, we advocate for methodological pluralism. We see complementary or even convergent roles for analyses based on quantitative (e.g., data-mining, systems modeling) and qualitative methods (e.g., mental models, qualitative storylines). The data-driven and knowledge-driven methods provided here can serve as a useful starting point for understanding the dynamics of both high-frequency CCI and low-likelihood but high-impact CCI. With this perspective, we hope to foster research on CCI to improve the development of adaptation strategies for reducing the risk of hydrological extremes.
- Published
- 2024
20. A stepwise titration protocol for oral appliance therapy in positional obstructive sleep apnea patients: proof of concept
- Author
-
de Ruiter, M. H. T., Aarab, G., de Vries, N., Lobbezoo, F., and de Lange, J.
- Published
- 2020
- Full Text
- View/download PDF
21. LOFAR: The LOw-Frequency ARray
- Author
-
van Haarlem, M. P., Wise, M. W., Gunst, A. W., Heald, G., McKean, J. P., Hessels, J. W. T., de Bruyn, A. G., Nijboer, R., Swinbank, J., Fallows, R., Brentjens, M., Nelles, A., Beck, R., Falcke, H., Fender, R., Hörandel, J., Koopmans, L. V. E., Mann, G., Miley, G., Röttgering, H., Stappers, B. W., Wijers, R. A. M. J., Zaroubi, S., Akker, M. van den, Alexov, A., Anderson, J., Anderson, K., van Ardenne, A., Arts, M., Asgekar, A., Avruch, I. M., Batejat, F., Bähren, L., Bell, M. E., Bell, M. R., van Bemmel, I., Bennema, P., Bentum, M. J., Bernardi, G., Best, P., Bîrzan, L., Bonafede, A., Boonstra, A. -J., Braun, R., Bregman, J., Breitling, F., van de Brink, R. H., Broderick, J., Broekema, P. C., Brouw, W. N., Brüggen, M., Butcher, H. R., van Cappellen, W., Ciardi, B., Coenen, T., Conway, J., Coolen, A., Corstanje, A., Damstra, S., Davies, O., Deller, A. T., Dettmar, R. -J., van Diepen, G., Dijkstra, K., Donker, P., Doorduin, A., Dromer, J., Drost, M., van Duin, A., Eislöffel, J., van Enst, J., Ferrari, C., Frieswijk, W., Gankema, H., Garrett, M. A., de Gasperin, F., Gerbers, M., de Geus, E., Grießmeier, J. -M., Grit, T., Gruppen, P., Hamaker, J. P., Hassall, T., Hoeft, M., Holties, H., Horneffer, A., van der Horst, A., van Houwelingen, A., Huijgen, A., Iacobelli, M., Intema, H., Jackson, N., Jelic, V., de Jong, A., Juette, E., Kant, D., Karastergiou, A., Koers, A., Kollen, H., Kondratiev, V. I., Kooistra, E., Koopman, Y., Koster, A., Kuniyoshi, M., Kramer, M., Kuper, G., Lambropoulos, P., Law, C., van Leeuwen, J., Lemaitre, J., Loose, M., Maat, P., Macario, G., Markoff, S., Masters, J., McKay-Bukowski, D., Meijering, H., Meulman, H., Mevius, M., Middelberg, E., Millenaar, R., Miller-Jones, J. C. A., Mohan, R. N., Mol, J. D., Morawietz, J., Morganti, R., Mulcahy, D. D., Mulder, E., Munk, H., Nieuwenhuis, L., van Nieuwpoort, R., Noordam, J. E., Norden, M., Noutsos, A., Offringa, A. R., Olofsson, H., Omar, A., Orrú, E., Overeem, R., Paas, H., Pandey-Pommier, M., Pandey, V. N., Pizzo, R., Polatidis, A., Rafferty, D., Rawlings, S., Reich, W., de Reijer, J. -P., Reitsma, J., Renting, A., Riemers, P., Rol, E., Romein, J. W., Roosjen, J., Ruiter, M., Scaife, A., van der Schaaf, K., Scheers, B., Schellart, P., Schoenmakers, A., Schoonderbeek, G., Serylak, M., Shulevski, A., Sluman, J., Smirnov, O., Sobey, C., Spreeuw, H., Steinmetz, M., Sterks, C. G. M., Stiepel, H. -J., Stuurwold, K., Tagger, M., Tang, Y., Tasse, C., Thomas, I., Thoudam, S., Toribio, M. C., van der Tol, B., Usov, O., van Veelen, M., van der Veen, A. -J., ter Veen, S., Verbiest, J. P. W., Vermeulen, R., Vermaas, N., Vocks, C., Vogt, C., de Vos, M., van der Wal, E., van Weeren, R., Weggemans, H., Weltevrede, P., White, S., Wijnholds, S. J., Wilhelmsson, T., Wucknitz, O., Yatawatta, S., Zarka, P., Zensus, A., and van Zwieten, J.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
LOFAR, the LOw-Frequency ARray, is a new-generation radio interferometer constructed in the north of the Netherlands and across europe. Utilizing a novel phased-array design, LOFAR covers the largely unexplored low-frequency range from 10-240 MHz and provides a number of unique observing capabilities. Spreading out from a core located near the village of Exloo in the northeast of the Netherlands, a total of 40 LOFAR stations are nearing completion. A further five stations have been deployed throughout Germany, and one station has been built in each of France, Sweden, and the UK. Digital beam-forming techniques make the LOFAR system agile and allow for rapid repointing of the telescope as well as the potential for multiple simultaneous observations. With its dense core array and long interferometric baselines, LOFAR achieves unparalleled sensitivity and angular resolution in the low-frequency radio regime. The LOFAR facilities are jointly operated by the International LOFAR Telescope (ILT) foundation, as an observatory open to the global astronomical community. LOFAR is one of the first radio observatories to feature automated processing pipelines to deliver fully calibrated science products to its user community. LOFAR's new capabilities, techniques and modus operandi make it an important pathfinder for the Square Kilometre Array (SKA). We give an overview of the LOFAR instrument, its major hardware and software components, and the core science objectives that have driven its design. In addition, we present a selection of new results from the commissioning phase of this new radio observatory., Comment: 56 pages, 34 figures, accepted for publication by A&A
- Published
- 2013
- Full Text
- View/download PDF
22. Optimized Trigger for Ultra-High-Energy Cosmic-Ray and Neutrino Observations with the Low Frequency Radio Array
- Author
-
Singh, K., Mevius, M., Scholten, O., Anderson, J. M., van Ardenne, A., Arts, M., Avruch, M., Asgekar, A., Bell, M., Bennema, P., Bentum, M., Bernadi, G., Best, P., Boonstra, A. -J., Bregman, J., van de Brink, R., Broekema, C., Brouw, W., Brueggen, M., Buitink, S., Butcher, H., van Cappellen, W., Ciardi, B., Coolen, A., Damstra, S., Dettmar, R., van Diepen, G., Dijkstra, K., Donker, P., Doorduin, A., Drost, M., van Duin, A., Eisloeffel, J., Falcke, H., Garrett, M., Gerbers, M., Griessmeier, J., Grit, T., Gruppen, P., Gunst, A., van Haarlem, M., Hoeft, M., Holties, H., Horandel, J., Horneffer, L. A., Huijgen, A., James, C., de Jong, A., Kant, D., Kooistra, E., Koopman, Y., Koopmans, L., Kuper, G., Lambropoulos, P., van Leeuwen, J., Loose, M., Maat, P., Mallary, C., McFadden, R., Meulman, H., Mol, J. -D., Morawietz, J., Mulder, E., Munk, H., Nieuwenhuis, L., Nijboer, R., Norden, M., Noordam, J., Overeem, R., Paas, H., Pandey, V. N., Pandey-Pommier, M., Pizzo, R., Polatidis, A., Reich, W., de Reijer, J., Renting, A., Riemers, P., Roettgering, H., Romein, J., Roosjen, J., Ruiter, M., Schoenmakers, A., Schoonderbeek, G., Sluman, J., Smirnov, O., Stappers, B., Steinmetz, M., Stiepel, H., Stuurwold, K., Tagger, M., Tang, Y., ter Veen, S., Vermeulen, R., de Vos, M., Vogt, C., van der Wal, E., Weggemans, H., Wijnholds, S., Wise, M., Wucknitz, O., Yattawatta, S., and van Zwieten, J.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics ,Astrophysics - High Energy Astrophysical Phenomena - Abstract
When an ultra-high energy neutrino or cosmic ray strikes the Lunar surface a radio-frequency pulse is emitted. We plan to use the LOFAR radio telescope to detect these pulses. In this work we propose an efficient trigger implementation for LOFAR optimized for the observation of short radio pulses., Comment: Submitted to Nuclear Instruments and Methods in Physics Research Section A
- Published
- 2011
- Full Text
- View/download PDF
23. THACO, a Test Facility for Characterizing the Noise Performance of Active Antenna Arrays
- Author
-
Woestenburg, E. E. M., Bakker, L., Ruiter, M., Ivashina, M. V., and Witvers, R. H.
- Subjects
Astrophysics - Instrumentation and Methods for Astrophysics - Abstract
This paper discusses an outdoor test facility for the noise characterization of active antenna arrays, using measurement results of array noise temperatures in the order of 50 K for a number of small aperture arrays. The measurement results are obtained by a Y-factor method with hot and a cold noise sources, with an absorber at room temperature as the hot load and the cold sky as the cold load. The effect of shielding the arrays by the test facility, with respect to noise and RFI from the environment, will also be discussed., Comment: 4 pages, 6 figures. Official Publication: Microwave Journal; Proc. of European Microwave Week (EuMW2011), October 9th-14th, 2011
- Published
- 2011
24. The mesencephalic astrocyte-derived neurotrophic factor (MANF) as a novel regulator of post-infarction cardiac sympathetic hyperinnervation
- Author
-
Blok, M, primary, Van Gils, J M, additional, Boukens, B J D, additional, Kielbasa, S M, additional, Van Schendel, B W, additional, Schoones, J W, additional, Smits, A M, additional, Goumans, M J T H, additional, De Ruiter, M C, additional, and Jongbloed, M R M, additional
- Published
- 2023
- Full Text
- View/download PDF
25. Anatomie
- Author
-
Dörr, P. J., Keizer, S., Weemhoff, M., de Ruiter, M. C., Khouw, V. M., Dörr, P. Joep, editor, Khouw, Vincent M., editor, Jacquemyn, Yves, editor, Chervenak, Frank A., editor, and Nijhuis, Jan G., editor
- Published
- 2017
- Full Text
- View/download PDF
26. Inter-observer variation of hippocampus delineation in hippocampal avoidance prophylactic cranial irradiation
- Author
-
Bartel, F., van Herk, M., Vrenken, H., Vandaele, F., Sunaert, S., de Jaeger, K., Dollekamp, N. J., Carbaat, C., Lamers, E., Dieleman, E. M. T., Lievens, Y., de Ruysscher, D., Schagen, S. B., de Ruiter, M. B., de Munck, J. C., and Belderbos, J.
- Published
- 2019
- Full Text
- View/download PDF
27. OC-0607 Pattern of brain metastases after HA-PCI and SRCF in SCLC: pooled findings of NCT01780675 and PREMER
- Author
-
Zeng, H., primary, Schagen, S., additional, Hendriks, L., additional, Sánchez-Benavides, G., additional, Jaspers, J., additional, Manero, R., additional, Lievens, Y., additional, Murcia-Mejía, M., additional, Kuenen, M., additional, Rico-Oses, M., additional, de Ruiter, M., additional, Couñago, F., additional, Dieleman, E., additional, de Jaeger, K., additional, Calvo-Crespo, P., additional, Lambrecht, M., additional, Samper, P., additional, Belderbos, J., additional, De Ruysscher, D., additional, and Rodríguez de Dios, N., additional
- Published
- 2023
- Full Text
- View/download PDF
28. Cross-European challenges for multi-risk assessment and management: insights from the first two years of MYRIAD-EU
- Author
-
Sakic Trogrlic, R., Ward, P., de Ruiter, M., Hochrainer-Stigler, S., Torresan, S., Gottardo, G., Daloz, A., Ma, L., Tatman, S., Fumero, N., Ciurean, R., Jager, W., Daniell, J., Stuparu, D., Reiter, K., Duncan, M., Sakic Trogrlic, R., Ward, P., de Ruiter, M., Hochrainer-Stigler, S., Torresan, S., Gottardo, G., Daloz, A., Ma, L., Tatman, S., Fumero, N., Ciurean, R., Jager, W., Daniell, J., Stuparu, D., Reiter, K., and Duncan, M.
- Published
- 2023
29. Value Based Perinatal Care: Women at the centre of learning healthcare networks
- Author
-
Bekker, M.N., Franx, A., Lamain-de Ruiter, M., Depla, Anne Louise, Bekker, M.N., Franx, A., Lamain-de Ruiter, M., and Depla, Anne Louise
- Published
- 2023
30. Effect of physical exercise on the hippocampus and global grey matter volume in breast cancer patients:A randomized controlled trial (PAM study)
- Author
-
Koevoets, E. W., Geerlings, M. I., Monninkhof, E. M., Mandl, R., Witlox, L., van der Wall, E., Stuiver, M. M., Sonke, G. S., Velthuis, M. J., Jobsen, J. J., van der Palen, J., Bos, M. E.M.M., Göker, E., Menke-Pluijmers, M. B.E., Sommeijer, D. W., May, A. M., Haringhuizen, Annebeth W., van der Steeg, Wim A., Terheggen, Frederiek, Blanken-Peeters, Charlotte, Fliervoet, Harold, Schlooz-Vries, Margrethe S., Frakking, Tanja G., van Tilburg, Marc W.A., Oldenhuis, Corina, Sier, Maartje F., van der Pol, Carmen C., Tick, Lidwine W., van Holsteijn, Nel A., de Ruiter, M. B., Schagen, S. B., Koevoets, E. W., Geerlings, M. I., Monninkhof, E. M., Mandl, R., Witlox, L., van der Wall, E., Stuiver, M. M., Sonke, G. S., Velthuis, M. J., Jobsen, J. J., van der Palen, J., Bos, M. E.M.M., Göker, E., Menke-Pluijmers, M. B.E., Sommeijer, D. W., May, A. M., Haringhuizen, Annebeth W., van der Steeg, Wim A., Terheggen, Frederiek, Blanken-Peeters, Charlotte, Fliervoet, Harold, Schlooz-Vries, Margrethe S., Frakking, Tanja G., van Tilburg, Marc W.A., Oldenhuis, Corina, Sier, Maartje F., van der Pol, Carmen C., Tick, Lidwine W., van Holsteijn, Nel A., de Ruiter, M. B., and Schagen, S. B.
- Abstract
Background: Physical exercise in cancer patients is a promising intervention to improve cognition and increase brain volume, including hippocampal volume. We investigated whether a 6-month exercise intervention primarily impacts total hippocampal volume and additionally hippocampal subfield volumes, cortical thickness and grey matter volume in previously physically inactive breast cancer patients. Furthermore, we evaluated associations with verbal memory. Methods: Chemotherapy-exposed breast cancer patients (stage I-III, 2–4 years post diagnosis) with cognitive problems were included and randomized in an exercise intervention (n = 70, age = 52.5 ± 9.0 years) or control group (n = 72, age = 53.2 ± 8.6 years). The intervention consisted of 2x1 hours/week of supervised aerobic and strength training and 2x1 hours/week Nordic or power walking. At baseline and at 6-month follow-up, volumetric brain measures were derived from 3D T1-weighted 3T magnetic resonance imaging scans, including hippocampal (subfield) volume (FreeSurfer), cortical thickness (CAT12), and grey matter volume (voxel-based morphometry CAT12). Physical fitness was measured with a cardiopulmonary exercise test. Memory functioning was measured with the Hopkins Verbal Learning Test-Revised (HVLT-R total recall) and Wordlist Learning of an online cognitive test battery, the Amsterdam Cognition Scan (ACS Wordlist Learning). An explorative analysis was conducted in highly fatigued patients (score of ≥ 39 on the symptom scale ‘fatigue’ of the European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire), as previous research in this dataset has shown that the intervention improved cognition only in these patients. Results: Multiple regression analyses and voxel-based morphometry revealed no significant intervention effects on brain volume, although at baseline increased physical fitness was significantly related to larger brain volume (e.g., total hippocampal volume: R = 0.32, B =
- Published
- 2023
31. The employment relationship amidst and beyond the COVID-19 pandemic: The role of (responsible) inclusive leadership in managing psychological contracts
- Author
-
de Ruiter, M., Schalk, R., de Ruiter, M., and Schalk, R.
- Abstract
In this conceptual chapter, we consider the extent to which the COVID-19 pandemic has affected what employees value in their employment relationship. Drawing from the psychological contract framework, we consider potential shifts in the types of obligations employees find important in the post-pandemic era. We propose that the main dimensions of the psychological contract—transactional, relational, and ideological—are upheld in post-COVID-19 psychological contracts. However, we expect that ideological obligations will generally become more important across industries and job types. Moreover, we posit that the type of obligations underlying the three dimensions will likely change and more importance is expected to be placed on dimensions such as safe working environments, inclusion, and diversity. We discuss the important role of (responsible) inclusive leadership in fulfilling psychological contracts and we present key challenges managers may face in employing (responsible) inclusive leadership in managing psychological contracts remotely beyond the COVID-19 pandemic. We specifically focus on challenges brought on by distrust, micromanaging, and generational differences. We conclude with the limitations of our conceptual endeavour and offer recommendations for future research and implications for practice.
- Published
- 2023
32. Brain processing of rectal sensation in adolescents with functional defecation disorders and healthy controls
- Author
-
Mugie, S. M., Koppen, I. J. N., van den Berg, M. M., Groot, P. F. C., Reneman, L., de Ruiter, M. B., and Benninga, M. A.
- Published
- 2018
- Full Text
- View/download PDF
33. Panta Rhei benchmark dataset: socio-hydrological data of paired events of floods and droughts (version 2)
- Author
-
Kreibich, H., Schröter, K., Di Baldassarre, G., Van Loon, A., Mazzoleni, M., Abeshu, G., Agafonova, S., AghaKouchak, A., Aksoy, H., Alvarez-Garreton, C., Aznar, B., Balkhi, L., Barendrecht, M., Biancamaria, S., Bos-Burgering, L., Bradley, C., Budiyono, Y., Buytaert, W., Capewell, L., Carlson, H., Cavus, Y., Couasnon, A., Coxon, G., Daliakopoulos, I., de Ruiter, M., Delus, C., Erfurt, M., Esposito, G., François, D., Frappart, F., Freer, J., Frolova, N., Gain, A., Grillakis, M., Grima, J., Guzmán, D., Huning, L., Ionita, M., Kharlamov, M., Khoi, D., Kieboom, N., Kireeva, M., Koutroulis, A., Lavado-Casimiro, W., Li, H., LLasat, M., Macdonald, D., Mård, J., Mathew-Richards, H., McKenzie, A., Mejia, A., Mendiondo, E., Mens, M., Mobini, S., Mohor, G., Nagavciuc, V., Ngo-Duc, T., Nguyen, H., Nhi, P., Petrucci, O., Quan, N., Quintana-Seguí, P., Razavi, S., Ridolfi, E., Riegel, J., Sadik, M., Sairam, N., Savelli, E., Sazonov, A., Sharma, S., Sörensen, J., Souza, F., Stahl, K., Steinhausen, M., Stoelzle, M., Szalińska, W., Tang, Q., Tian, F., Tokarczyk, T., Tovar, C., Tran, T., van Huijgevoort, M., van Vliet, M., Vorogushyn, S., Wagener, T., Wang, Y., Wendt, D., Wickham, E., Yang, L., Zambrano-Bigiarini, M., and Ward, P.
- Abstract
As the negative impacts of hydrological extremes increase in large parts of the world, a better understanding of the drivers of change in risk and impacts is essential for effective flood and drought risk management and climate adaptation. However, there is a lack of comprehensive, empirical data about the processes, interactions and feedbacks in complex human-water systems leading to flood and drought impacts. To fill this gap, we present an IAHS Panta Rhei benchmark dataset containing socio-hydrological data of paired events, i.e. two floods or two droughts that occurred in the same area (Kreibich et al. 2017, 2019). The contained 45 paired events occurred in 42 different study areas (in three study areas we have data on two paired events), which cover different socioeconomic and hydroclimatic contexts across all continents. The dataset is unique in covering floods and droughts, in the number of cases assessed and in the amount of qualitative and quantitative socio-hydrological data contained. References to the data sources are provided in 2023-001_Kreibich-et-al_Key_data_table.xlsx where possible. Based on templates, we collected detailed, review-style reports describing the event characteristics and processes in the case study areas, as well as various semi-quantitative data, categorised into management, hazard, exposure, vulnerability and impacts. Sources of the data were classified as follows: scientific study (peer-reviewed paper and PhD thesis), report (by governments, administrations, NGOs, research organisations, projects), own analysis by authors, based on a database (e.g. official statistics, monitoring data such as weather, discharge data, etc.), newspaper article, and expert judgement. The campaign to collect the information and data on paired events started at the EGU General Assembly in April 2019 in Vienna and was continued with talks promoting the paired event data collection at various conferences. Communication with the Panta Rhei community and other flood and drought experts identified through snowballing techniques was important. Thus, data on paired events were provided by professionals with excellent local knowledge of the events and risk management practices.
- Published
- 2023
34. Long-term (180-day) outcomes in critically ill patients with COVID-19 in the REMAP-CAP randomized clinical trial
- Author
-
Florescu, S, Stanciu, D, Zaharia, M, Kosa, A, Codreanu, D, Kidwai, A, Masood, S, Kaye, C, Coutts, A, MacKay, L, Summers, C, Polgarova, P, Farahi, N, Fox, E, McWilliam, S, Hawcutt, D, Rad, L, O’Malley, L, Whitbread, J, Jones, D, Dore, R, Saunderson, P, Kelsall, O, Cowley, N, Wild, L, Thrush, J, Wood, H, Austin, K, Bélteczki, J, Magyar, I, Fazekas, Á, Kovács, S, Szőke, V, Donnelly, A, Kelly, M, Smyth, N, O’Kane, S, McClintock, D, Warnock, M, Campbell, R, McCallion, E, Azaiz, A, Charron, C, Godement, M, Geri, G, Vieillard-Baron, A, Johnson, P, McKenna, S, Hanley, J, Currie, A, Allen, B, McGoldrick, C, McMaster, M, Mani, A, Mathew, M, Kandeepan, R, Vignesh, C, TV, B, Ramakrishnan, N, James, A, Elvira, E, Jayakumar, D, Pratheema, R, Babu, S, Ebenezer, R, Krishnaoorthy, S, Ranganathan, L, Ganesan, M, Shree, M, Guilder, E, Butler, M, Cowdrey, K-A, Robertson, M, Ali, F, McMahon, E, Duffy, E, Chen, Y, Simmonds, C, McConnochie, R, O’Connor, C, El-Khawas, K, Richardson, A, Hill, D, Commons, R, Abdelkharim, H, Saxena, M, Muteithia, M, Dobell-Brown, K, Jha, R, Kalogirou, M, Ellis, C, Krishnamurthy, V, O’Connor, A, Thurairatnam, S, Mukherjee, D, Kaliappan, A, Vertue, M, Nicholson, A, Riches, J, Maloney, G, Kittridge, L, Solesbury, A, Ramos, A, Collins, D, Brickell, K, Reid, L, Smyth, M, Breen, P, Spain, S, Curley, G, McEvoy, N, Geoghegan, P, Clarke, J, Silversides, J, McGuigan, P, Ward, K, O’Neill, A, Finn, S, Wright, C, Green, J, Collins, É, Knott, C, Smith, J, Boschert, C, Slieker, K, Ewalds, E, Sanders, A, Wittenberg, W, Geurts, H, Poojara, L, Sara, T, Nand, K, Reeve, B, Dechert, W, Phillips, B, Oritz-Ruiz de Gordoa, L, Affleck, J, Shaikh, A, Murray, A, Ramanan, M, Frakking, T, Pinnell, J, Robinson, M, Gledhill, L, Wood, T, Sanghavi, R, Bhonagiri, D, Ford, M, Parikh, HG, Avard, B, Nourse, M, McDonald, B, Edmunds, N, Hoiting, O, Peters, M, Rengers, E, Evers, M, Prinssen, A, Morgan, M, Cole, J, Hill, H, Davies, M, Williams, A, Thomas, E, Davies, R, Wise, M, Grimm, P, Soukup, J, Wetzold, R, Löbel, M, Starke, L, Lellouche, F, Lizotte, P, Declerq, P, Antoine, M, Stephanie, G, Jean-Pierre, E, François, B, Marion, B, Philippe, R, Pourcine, F, Monchi, M, Luis, D, Mercier, R, Sagnier, A, Verrier, N, Caplin, C, Richecoeu, J, Combaux, D, Siami, S, Aparicio, C, Vautier, S, Jeblaoui, A, Lemaire-Brunel, D, D'Aragon, F, Carbonneau, E, Leblond, J, Plantefeve, G, Leparco, C, Contou, D, Fartoukh, M, Courtin, L, Labbe, V, Voiriot, G, Salhi, S, Chassé, M, Carrier, F, Boumahni, D, Benettaib, F, Ghamraoui, A, Sement, A, Gachet, A, Hanisch, A, Haffiane, A, Boivin, A-H, Barreau, A, Guerineau, E, Poupblanc, S, Egreteau, P, Lefevre, M, Bocher, S, Le Loup, G, Le Guen, L, Carn, V, Bertel, M, Antcliffe, D, Templeton, M, Rojo, R, Coghlan, P, Smee, J, Barker, G, Finn, A, Kreb, G, Hoff, U, Hinrichs, C, Nee, J, Mackay, E, Cort, J, Whileman, A, Spencer, T, Spittle, N, Beavis, S, Padmakumar, A, Dale, K, Hawes, J, Moakes, E, Gascoyne, R, Pritchard, K, Stevenson, L, Cooke, J, Nemeth-Roszpopa, K, Gauli, B, Bastola, S, Muller, G, Nay, M-A, Kamel, T, Benzekri, D, Jacquier, S, Runge, I, Mathonnet, A, Barbier, F, Bretagnol, A, Carter, J, Van Der Heyden, K, Mehrtens, J, Morris, A, Morgan, S, Burke, T, Mercier, E, Chartier, D, Salmon, C, Dequin, P-F, Garot, D, Bellemare, D, Cloutier, È, Daher, R, Costerousse, O, Boulanger, M-C, Couillard-Chénard, É, Lauzier, F, Francoeur, C, Francois, B, Gay, A, Anne-Laure, F, Ramali, M, HC, O, Ghosh, A, Osagie, R, Arachchige, M, Hartley, M, Cheung, W, Wong, H, Seigne, P, Eustace, J, O'Callaghan, A-M, O'Brien, F, Bamford, P, Reid, A, Cawley, K, Faulkner, M, Pickering, C, Raj, A, Tsinaslanidis, G, Khade, R, Agha, G, Sekiwala, R, Smith, T, Brewer, C, Gregory, J, Limb, J, Cowton, A, O’Brien, J, Postlethwaite, K, Malakouti, S, Music, E, Ricketts, D, King, A, Clermont, G, Bart, R, Mayr, F, Schoenling, A, Andreae, M, Shetty, V, Brant, E, Malley, B, Donadee, C, Sackrowitz, R, Weissman, A, Yealy, D, Barton, D, Talia, N, Nikitas, N, Wells, C, Lankester, L, McMillan, H, Van den Oever, H, Kruisdijk-Gerritsen, A, Haidar, G, Bain, W, Barbash, I, Fitzpatrick, M, Franz, C, Kitsios, G, Moghbeli, K, Rosborough, B, Shah, F, Suber, T, Pulletz, M, Williams, P, Birch, J, Wiseman, S, Horton, S, Alegria, A, Turki, S, Elsefi, T, Crisp, N, Allen, L, Truman, N, Smith, M, Chukkambotla, S, Goddard, W, Duberley, S, Khan, M, Kazi, A, Simpson, J, Duke, G, Chan, P, Carter, B, Hunter, S, Voigt, I, Schueler, R, Blank, E, Hüning, V, Steffen, M, Goralski, P, Litton, E, Regli, A, Pellicano, S, Palermo, A, Eroglu, E, Bihari, S, Laver, RD, Jin, X, Brown, J, McIntyre, J, French, C, Bates, S, Towns, M, Yang, Y, McGain, F, McCullagh, I, Cairns, T, Hanson, H, Patel, B, Clement, I, Evetts, G, Touma, O, Holland, S, Hodge, C, Taylor, H, Alderman, M, Barnes, N, Da Rocha, J, Smith, C, Brooks, N, Weerasinghe, T, Sinclair, J-A, Abusamra, Y, Doherty, R, Cudlipp, J, Singh, R, Yu, H, Daebis, A, Ng, C, Kendrick, S, Saran, A, Makky, A, Greener, D, Rowe-Leete, L, Edwards, A, Bland, Y, Dolman, R, Foster, T, Laffey, J, McNicholas, B, Scully, M, Casey, S, Kernan, M, Brennan, A, Rangan, R, Tully, R, Corbett, S, McCarthy, A, Duffy, O, Burke, D, Linnett, V, Sanderson, A, Ritzema, J, Wild, H, Lucas, R, Marriott, Y, Andric, Z, Cviljevic, S, Br, R, Zapalac, M, Mirković, G, Khare, D, Pinder, M, Gopinath, A, Kannan, T, Dean, S, Vanmali, P, Depuydt, P, De Waele, J, De Bus, L, Fierens, J, Bracke, S, Vermassen, J, Vermeiren, D, Pugh, R, Lean, R, Qiu, X, Scanlan, J, Evans, A, Davies, G, Lewis, J, Plesnikova, Y, Khoud, A, Coetzee, S, Puxty, K, Cathcart, S, Rimmer, D, Bagot, C, Scott, K, Martin, L, Yusuff, H, Isgro, G, Brightling, C, Bourne, M, Craner, M, Boyles, R, Alexander, B, Roberts, T, Nelli, A, Rosenstein-Sisson, R, Speyer, R, Pech, Y, McCullough, J, Tallott, M, Vazquez-Grande, G, Marten, N, Liu, T, Siddiqui, A, Khanal, S, Amatya, S, Szakmany, T, Cherian, S, Williams, G, James, C, Waters, A, Prout, R, Stedman, R, Davies, L, Pegler, S, Kyeremeh, L, Moorhouse, L, Arbane, G, Marotti, M, Bociek, A, Campos, S, Van Nieuwkoop, K, Ottens, T, Visser, Y, Van den Berg, L, Van der Kraan-Donker, A, Brett, S, Arias, S, Hall, R, Paneru, H, Koirala, S, Paudel, P, Wilson, M, Vaara, S, Pettilä, L, Heinonen, J, Pettilä, V, Jain, S, Gupta, A, Holbrook, C, Antoine, P, Meziani, F, Allam, H, Cattelan, J, Clere-Jehl, R, Helms, J, Kummerlen, C, Merdji, H, Monnier, A, Rahmani, H, Studer, A, Schneider, F, Castelain, V, Morel, G, L’Hotellier, S, Ochin, E, Vanjak, C, Rouge, P, Bendjemar, L, Albert, M, Serri, K, Cavayas, A, Duplaix, M, Williams, V, Catorze, NJTADS, Pereira, TNAL, Ferreira, RMC, Bastos, JMPS, Batista, TMO, Badie, J, Berdaguer, F, Malfroy, S, Mezher, C, Bourgoin, C, Moneger, G, Bouvier, E, Muñoz-Bermúdez, R, Marin-Corral, J, Degracia, A, Gómez, F, López, M, Aceto, R, Aghemo, A, Badalamenti, S, Brunetta, E, Cecconi, M, Ciccarelli, M, Constantini, E, Greco, M, Folci, M, Selmi, C, Voza, A, Henning, J, Bonner, S, Hugill, K, Cirstea, E, Wilkinson, D, Jones, J, Altomy, M, Karlikowski, M, Sutherland, H, Wilhelmsen, E, Woods, J, North, J, Pletz, M, Hagel, S, Ankert, J, Kolanos, S, Bloos, F, Simons, K, Van Zuylen, T, Bouman, A, Kumar, N, Panwar, R, Poulter, A-L, Sunkara, K, Szigligeti, G, Leszkoven, J, Rochwerg, B, Karachi, T, Oczkowski, S, Centofanti, J, Millen, T, Sundaran, D, Hollos, L, Turns, M, Walsh, J, Al Qasim, E, Alswaidan, L, Hegazy, M, Arishi, H, Al Amri, A, AlQahtani, S, Naidu, B, Tlayjeh, H, Hussain, S, Al Enezi, F, Abdukahil, SA, Hopkins, P, Noble, H, O’Reilly, K, Mehta, R, Wong, O, Makanju, E, Rao, D, Sikondari, N, Saha, S, Corcoran, E, Pappa, E, Cockrell, M, Donegan, C, Balaie, M, Nickoleit-Bitzenberger, D, Schaaf, B, Meermeier, W, Prebeg, K, Azzaui, H, Hower, M, Brieger, K-G, Elender, C, Sabelhaus, T, Riepe, A, Akamp, C, Kremling, J, Klein, D, Landsiedel-Mechenbier, E, Laha, S, Verlander, M, Jha, A, Megarbane, B, Voicu, S, Deye, N, Malissin, I, Sutterlin, L, Mrad, A, Lehalleur, A, Naim, G, Nguyen, P, Ekhérian, J-M, Boué, Y, Sidéris, G, Vodovar, D, Guérin, E, Grant, C, Brain, M, Mineall, S, Paramasivam, E, Wilby, E, Ogg, B, Howcroft, C, Aspinwall, A, Charlton, S, Gould, R, Mistry, D, Awan, S, Bedford, C, Carr-Wilkinson, J, Hall, A, Gardiner-Hill, C, Maloney, C, Brunskill, N, Watchorn, O, Hardy, C, Qureshi, H, Flint, N, Nicholson, S, Southin, S, Ghattaoraya, A, Harding, D, O’Halloran, S, Collins, A, Smith, E, Trues, E, Borgatta, B, Turner-Bone, I, Reddy, A, Wilding, L, Wilson, C, Surti, Z, Aneman, A, Miller, J, White, H, Estensen, K, Morrison, L, Sutton, J, Cooper, M, Warnapura, L, Agno, R, Sathianathan, P, Shaw, D, Ijaz, N, Spong, A, Sabaretnam, S, Burns, D, Lang, E, Tate, M, Fischer, R, Biradar, V, Soar, N, Golden, D, Davey, M, Seaman, R, Osborne, A, Bannard-Smith, J, Clark, R, Birchall, K, Henry, J, Pomeroy, F, Quayle, R, Wylie, K, Sukuraman, A, John, M, Sibin, S, Leditschke, A, Finnis, M, Jongebloed, K, Khwaja, K, Campisi, J, Van Vonderen, M, Pietersma, M, Vrolijk, L, Kampschreur, L, Van Gulik, L, Makowski, A, Misztal, B, Haider, S, Liao, A, Squires, R, Oborska, A, Kayani, A, Kalchko-Veyssal, S, Prabakaran, R, Hadebe, B, KalchkoVeyssal, S, Williams, T, Song, R, Morpeth, S, Lai, V, Habraken, H, Stewart, R, Mwaura, E, Mew, L, Wren, L, Willams, F, Sutherland, S-B, Rebello, R, Shehabi, Y, Al-Bassam, W, Hulley, A, Kadam, U, Sathianathan, K, Innes, R, Doble, P, Graham, L, Shovelton, C, Dean, T, Salahuddin, N, Aryal, D, Koirala, K, Rai, N, Luitel, S, Seppelt, I, Whitehead, C, Lowrey, J, Gresham, R, Masters, K, Hamlyn, V, Hawkins, N, Roynon-Reed, A, Cutler, S, Lewis, S, Lazaro, J, Newman, T, Aravindan, L, Asghar, A, Bartholomew, J, Bayne, M, Beddows, S, Birch, C, Brend, M, Byrne, R, Campbell, D, Campbell, H, Chambers, E, Clinton, A, Collins, J, Crawshaw, S, Dawson, LA, Donaldson, K, Drake, C, Dyas, S, Ellis, Y, Gilmour, K, Goodwin, J, Halden, S, Hall, AS, Hanson, J, Harper, H, Harrison, S, Hayes, A, Hodgson, H, Hurford, S-A, Jackson, S, Levett, C, Lock, S, Lockett, T, Logan, M, Lomme, K, Luo, J, Marsh, E, Mguni, N, Monaghan, H, Murphy, S, Muzengi, N, Naz, M, O'Kell, E, Oliver, A, O'Reilly, J, Pearson, K, Porter, D, Potter, A, Rook, C, Rounds, C, Sheffield, J, Shirley, K, Siewersk, C, Skinner, T, Speight, H, Sutu, M, Unsworth, A, Van’t Hoff, W, Walker, S, Williams, H, Williamson, D, Williamson, JD, Duan, E, Tsang, J, Patterson, L, Austin, P, Chapman, S, Cabrelli, L, Fletcher, S, Nortje, J, Fottrell-Gould, D, Randell, G, Stammers, K, Healey, G, Pinto, M, Borrill, Z, Duncan, T, Ustianowski, A, Uriel, A, Eltayeb, A, Alfonso, J, Hey, S, Shaw, J, Fox, C, Lindergard, G, Charles, B, Blackledge, B, Connolly, K, Harris, J, Cuesta, J, Xavier, K, Purohit, D, Elhassan, M, Haldeos, A, Vincent, R, Abdelrazik, M, Jenkins, S, Ganesan, A, Kumar, R, Carter, D, Bakthavatsalam, D, Frater, A, Saleem, M, Everitt, R, Hacking, D, Zaman, M, Elmahi, E, Jones, A, Hall, K, Phillips, M, Terrill, L, Mills, G, Raithatha, A, Bauchmuller, K, Ryalls, K, Harrington, K, Bowler, H, Sall, J, Bourne, R, Gross, J, Massey, N, Adebambo, O, Long, M, Tony, K, Juffermans, N, Koopmans, M, Dujardin, R, Alderink, B, Rowland, M, Hutton, P, Bashyal, A, Davidson, N, Hird, C, Chhablani, M, Phalod, G, Kirkby, A, Archer, S, Netherton, K, Reschreiter, H, Camsooksai, J, Patch, S, Humphrey, C, Flynn, G, Harrington, C, Kruger, P, Walsham, J, Meyer, J, Harward, M, Jones, C, Sathe, S, Roche, L, Davies, E, Skinner, D, Gaylard, J, Newman, J, Pogson, D, Rose, S, Daly, Z, Brimfield, L, Nown, A, Parekh, D, Bergin, C, Bates, M, McGhee, C, Lynch, D, Bhandal, K, Tsakiridou, K, Bamford, A, Cooper, L, Whitehouse, T, Veenith, T, Forster, E, O'Connell, M, Sim, M, Hay, S, Henderson, S, Nygren, M, Valentine, E, Katary, A, Bell, G, Wilcox, L, Mataliotakis, M, Smith, P, Ali, M, Isguzar, A, Phull, M-K, Zaidi, A, Pogreban, T, Rosaroso, L, Harvey, D, Lowe, B, Meredith, M, Ryan, L, Schouten, J, Pickkers, P, Roovers, N, Klop-Riehl, M, Van der Eng, H, Sloots-Cuppen, S, Preijers, L, Van Oosten, N, Moine, P, Heming, N, Maxime, V, Bossard, I, Nicholier, T, Clair, B, Orlikowski, D, Bounab, R, Abdeladim, L, Baker, S, Duroux, M, Ratcliffe, M, Sy, E, Mailman, J, Lee, S, Gupta, C, Kassir, S, López, R, Rodríguez-Gómez, J, Cárcel, S, Carmona, R, De la Fuente, C, Rodriguez, M, Jan Hassing, R, Greven, F, Huijbens, D, Roebers, L, Verheij, H, Miles, H, Attokaran, A, Buehner, U, Williams, E, Chapman, M, O’Connor, S, Glasby, K, Rivett, J, Brown, N, Kutsogiannis, D, Thompson, P, Rooney, K, Rodden, N, Thomson, N, McGlynn, D, Abel, L, Gemmell, L, Sundaram, R, Hornsby, J, Walden, A, Keating, L, Frise, M, Rai, S, Bartley, S, Schuster-Bruce, M, Pitts, S, Miln, R, Purandare, L, Vamplew, L, Dempster, D, Gummadi, M, Dormand, N, Wang, S, Spivey, M, Bean, S, Burt, K, Moore, L, Hammonds, F, Richards, C, Campbell, L, Smyth, K, Day, C, Zitter, L, Benyon, S, Singh, J, Lynch, C, Mikusek, J, Deacon, B, Turner, K, Baker, E, Hickey, J, Champanerkar, S, Aitken, L, LewisProsser, L, Ahmad, N, Wiles, M, Willson, J, Grecu, I, Martin, J, Wrey Brown, C, Arias, A-M, Bevan, E, Westlake, S, Craven, T, Hope, D, Singleton, J, Clark, S, McCulloch, C, Biddie, S, Welters, I, Hamilton, D, Williams, K, Waugh, V, Mulla, S, Waite, A, Roman, J, Martinez, M, Johnston, B, Puthucheary, Z, Martin, T, Santos, F, Uddin, R, Fernandez, M, Seidu, F, Somerville, A, Pakats, M-L, Begum, S, Shahid, T, Presneill, J, Barge, D, Byrne, K, Janin, P, Yarad, E, Bass, F, Hammond, N, Vuylsteke, A, Chan, C, Victor, S, Waterson, S, McNamara, R, Boardman, M, Gattas, D, Buhr, H, Coles, J, Matsa, R, Gellamucho, M, Creagh-Brown, B, Marriot, C, Salberg, A, Zouita, L, Stone, S, Michalak, N, Donlon, S, Mtuwa, S, Mayangao, I, Verula, J, Burda, D, Harris, C, Jones, E, Bradley, P, Tarr, E, Harden, L, Piercy, C, Nolan, J, Kerslake, I, Cook, T, Simpson, T, Dalton, J, Demetriou, C, Mitchard, S, Ramos, L, White, K, Johnson, T, Headdon, W, Spencer, S, White, A, Howie, L, Reay, M, Watts, A, Traverse, E, Jennings, S, Anumakonda, V, Tuckwell, C, Harrow, K, Matthews, J, McGarry, K, Moore, V, Smith, L, Summerfield, A, Dark, P, Harvey, A, Doonan, R, McMorrow, L, Knowles, K, Pendlebury, J, Perez, J, Marsden, T, Taylor, M, Michael, A, Collis, M, Claxton, A, Habeichi, W, Horner, D, Slaughter, M, Thomas, V, Proudfoot, N, Keatley, C, Donnison, P, Casey, R, Irving, B, Matimba-Mupaya, W, Reed, C, Anthony, A, Trim, F, Cambalova, L, Robertson, D, Wilson, A, Hulme, J, Kannan, S, Kinney, F, Senya, H, Ratnam, V, Gill, M, Kirk, J, Shelton, S, Schweikert, S, Wibrow, B, Anstey, M, Rauniyar, R, Khoso, N, Asif, N, Taqdees, H, Frey, C, Scano, R, McKee, M, Murphy, P, Thomas, M, Worner, R, Faulkner, B, Gendall, E, Hayes, K, Blakemore, H, Borislavova, B, Deshpande, K, Van Haren, F, Konecny, P, Inskip, D, Tung, R, Hayes, L, Murphy, L, Neill, A, Reidy, B, O’Dwyer, M, Ryan, D, Ainscough, K, Hamilton-Davies, C, Mfuko, C, Abbass, H, Mandadapu, V, Leaver, S, Patel, K, Farnell-Ward, S, Saluzzio, R, Rawlins, S, Sicat, C, De Keulenaer, B, Ferrier, J, Fysh, E, Davda, A, Mevavala, B, Cook, D, Clarke, F, Banach, D, Fernández de Pinedo Artaraz, Z, Cabreros, L, Latham, V, Kruisselbrink, R, Brochard, L, Burns, K, Sandhu, G, Khalid, I, White, I, Croft, M, Holland, N, Pereira, R, Nair, P, Buscher, H, Reynolds, C, Newman, S, Santamaria, J, Barbazza, L, Homes, J, Smith, R, Zaki, A, Johnson, D, Garrard, H, Juhaz, V, Brown, L, Pemberton, A, Roy, A, Rostron, A, Woods, L, Cornell, S, Fowler, R, Adhikari, N, Kamra, M, Marinoff, N, Garrett, P, Murray, L, Brailsford, J, Fennessy, G, Mulder, J, Morgan, R, Pillai, S, Harford, R, Ivatt, H, Evans, D, Richards, S, Roberts, E, Bowen, J, Ainsworth, J, Kuitunen, A, Karlsson, S, Vahtera, A, Kiiski, H, Ristimäki, S, Albrett, J, Jackson, C, Kirkham, S, Tamme, K, Reinhard, V, Ellervee, A, Põldots, L, Rennit, P, Svitškar, N, Browne, T, Grimwade, K, Goodson, J, Keet, O, Callender, O, Udy, A, McCracken, P, Young, M, Board, J, Martin, E, Kasipandian, V, Patel, A, Allibone, S, Mary-Genetu, R, English, S, Watpool, I, Porteous, R, Miezitis, S, McIntyre, L, Brady, K, Vale, C, Shekar, K, Lavana, J, Parmar, D, Peake, S, Kurenda, C, Hormis, A, Walker, R, Collier, D, Kimpton, S, Oakley, S, Bhagani, S, De Neef, M, Garcia, S, Maharajh, A, Nandani, A, Dobson, J, Fernando, G, Eastgate, C, Gomez, K, Abdi, Z, Tatham, K, Jhanji, S, Black, E, Dela Rosa, A, Howle, R, Baikady, R, Drummond, A, Dearden, J, Philbin, J, Munt, S, Gopal, S, Pooni, J-S, Ganguly, S, Smallwood, A, Metherell, S, Naeem, A, Fagan, L, Ryan, E, Mariappa, V, Foulds, A, Revill, A, Bhattarai, B, De Jonge, E, Wigbers, J, Del Prado, M, Cremer, O, Mulier, J, Peters, A, Romberg, B, Schutgens, R, Troeman, D, Van Opdorp, M, Besten, H, Brakké, K, Barber, R, Hilldrith, A, Kluge, S, Nierhaus, A, Jarczak, D, Roedl, K, Kochanek, M, Rueß-Paterno, G, Mc-Kenzie, J, Eichenauer, D, Shimabukuro-Vornhagen, A, Wilcox, E, Del Sorbo, L, Abdelhady, H, Romagnuolo, T, Simpson, S, Maiden, M, Horton, M, Trickey, J, Krajinovic, V, Kutleša, M, Kotarski, V, Brohi, F, Jagannathan, V, Clark, M, Purvis, S, Wetherill, B, Brajković, A, Babel, J, Sever, H, Dragija, L, Kušan, I, Dushianthan, A, Cusack, R, De Courcy-Golder, K, Salmon, K, Burnish, R, Smith, S, Ruiz, W, Duke, Z, Johns, M, Male, M, Gladas, K, Virdee, S, Swabe, J, Tomlinson, H, Rohde, G, Grünewaldt, A, Bojunga, J, Petros, S, Kunz, K, Schütze, B, Weismann, D, Frey, A, Drayss, M, Goebeler, ME, Flor, T, Fragner, G, Wahl, N, Totzke, J, Sayehli, C, Hakak, S, Altaf, W, O'Sullivan, M, Murphy, A, Walsh, L, Rega La Valle, A, Bewley, J, Sweet, K, Grimmer, L, Johnson, R, Wyatt, R, Morgan, K, Varghese, S, Willis, J, Stratton, E, Kyle, L, Putensen, D, Drury, K, Skorko, A, Bremmer, P, Ward, G, Bassford, C, Sligl, W, Baig, N, Rewa, O, Bagshaw, S, Basile, K, Stavor, D, Burbee, D, McNamara, A, Wunderley, R, Bensen, N, Adams, P, Vita, T, Buhay, M, Scholl, D, Gilliam, M, Winters, J, Doherty, K, Berryman, E, Ghaffari, M, Marroquin, O, Quinn, K, Garrard, W, Kalchthaler, K, Beard, G, Skrtich, A, Bagavathy, K, Drapola, D, Bryan-Morris, K, Arnold, J, Reynolds, B, Hussain, M, Dunsavage, J, Saiyed, S, Hernandez, E, Goldman, J, Brown, C, Comp, S, Raczek, J, Morris, J, Vargas Jr., J, Weiss, D, Hensley, J, Kochert, E, Wnuk, C, Nemeth, C, Mowery, B, Hutchinson, C, Winters, L, McAdams, D, Walker, G, Minnier, T, Wisniewski, M, Mayak, K, McCreary, E, Bariola, R, Viehman, A, Daley, J, Lopus, A, Schmidhofer, M, Ambrosino, R, Keen, S, Toffalo, S, Stambaugh, M, Trimmer, K, Perri, R, Casali, S, Medva, R, Massar, B, Beyerl, A, Burkey, J, Keeler, S, Lowery, M, Oncea, L, Daugherty, J, Sevilla, C, Woelke, A, Dice, J, Weber, L, Roth, J, Ferringer, C, Beer, D, Fesz, J, Carpio, L, Colin, G, Zinzoni, V, Maquigneau, N, Henri-Lagarrigue, M, Pouplet, C, Reill, L, Distler, M, Maselli, A, Martynoga, R, Trask, K, Butler, A, Attwood, B, Parsons, P, Campbell, B, Smith, A, Page, V, Zhao, X, Oza, D, Abrahamson, G, Sheath, B, Young, P, Young, C, Lesona, E, Navarra, L, Cruz, R, Delaney, K, Aguilar-Dano, A, Gojanovic, M, Rhodes, J, Anderson, T, Morris, S, Nayyar, V, Bowen, D, Kong, J, Joy, J, Fuchs, R, Lambert, B, Tai, C, Thomas, A, Keen, A, Tierney, C, Omer, N, Bacon, G, Tridente, A, Shuker, K, Anders, J, Greer, S, Scott, P, Millington, A, Buchanan, P, Binnie, A, Powell, E, McMillan, A, Luk, T, Aref, N, Denmade, C, Sadera, G, Jacob, R, Hughes, D, Sterba, M, Geng, W, Digby, S, Southern, D, Reddy, H, Hulse, S, Campbell, A, Garton, M, Watkins, C, Smuts, S, Quinn, A, Simpson, B, McMillan, C, Finch, C, Hill, C, Cooper, J, Budd, J, Small, C, O’Leary, R, Collins, E, Holland, A, Alexander, P, Felton, T, Ferguson, S, Sellers, K, Ward, L, Yates, D, Birkinshaw, I, Kell, K, Scott, Z, Pearson, H, Hashmi, M, Hassan, N, Panjwani, A, Umrani, Z, Shaikh, M, Ain, Q, Kanwal, D, Van Bree, S, Bouw-Ruiter, M, Osinga, M, Van Zanten, A, McEldrew, R, Rashan, S, Singh, V, Azergui, N, Bari, S, Beltran, M, Brugman, C, Groeneveld, E, Jafarzadeh, M, Keijzer-Timmers, N, Kester, E, Koelink, M, Kwakkenbos-Craanen, M, Okundaye, C, Parker, L, Peters, S, Post, S, Rietveld, I, Scheepstra-Beukers, I, Schreuder, G, Smit, A, Brillinger, N, Markgraf, R, Eichinger, F, Doran, P, Anjum, A, Best-Lane, J, Barton, F, Miller, L, Richards-Belle, A, Saull, M, Sprinckmoller, S, Wiley, D, Darnell, R, Au, C, Lindstrum, K, Cheng, A, Forbes, A, Heritier, S, Trapani, T, Cuthbertson, B, Manoharan, V, Dondrop, A, Tolppa, T, Ehrmann, S, Hullegie, S, Povoa, P, Beasley, R, Daneman, N, McGloughlin, S, Paterson, D, Venkatesh, B, De Jong, M, Uyeki, T, Baillie, K, Netea, M, Orr, K, Patanwala, A, Tong, S, Cooper, N, Galea, J, Leavis, H, Ogungbenro, K, Patawala, A, Rademaker, E, Youngstein, T, Carrier, M, Fergusson, D, Hunt, B, Kumar, A, Laffan, M, Lother, S, Middeldorp, S, Stanworth, S, De Man, A, Masse, M-H, Abraham, J, Arnold, D, Begin, P, Charlewood, R, Chasse, M, Coyne, M, Daly, J, Gosbell, I, Harvala-Simmonds, H, MacLennan, S, McDyer, J, Menon, D, Pridee, N, Roberts, D, Thomas, H, Tinmouth, A, Triulzi, D, Walsh, T, Wood, E, Calfee, C, O’Kane, C, Shyamsundar, M, Sinha, P, Thompson, T, Young, I, Burrell, A, Ferguson, N, Hodgson, C, Orford, N, Phua, J, Baron, R, Epelman, S, Frankfurter, C, Gommans, F, Kim, E, Leaf, D, Vaduganathan, M, Van Kimmenade, R, Sanil, A, Van Beurden, M, Effelaar, E, Schotsman, J, Boyd, C, Harland, C, Shearer, A, Wren, J, Attanayaka, U, Darshana, S, Ishani, P, Udayanga, I, Higgins, AM, Berry, LR, Lorenzi, E, Murthy, S, McQuilten, Z, Mouncey, PR, Al-Beidh, F, Annane, D, Arabi, YM, Beane, A, Van Bentum-Puijk, W, Bhimani, Z, Bonten, MJM, Bradbury, CA, Brunkhorst, FM, Buzgau, A, Buxton, M, Charles, WN, Cove, M, Detry, MA, Estcourt, LJ, Fagbodun, EO, Fitzgerald, M, Girard, TD, Goligher, EC, Goossens, H, Haniffa, R, Hills, T, Horvat, CM, Huang, DT, Ichihara, N, Lamontagne, F, Marshall, JC, McAuley, DF, McGlothlin, A, McGuinness, SP, McVerry, BJ, Neal, MD, Nichol, AD, Parke, RL, Parker, JC, Parry-Billings, K, Peters, SEC, Reyes, LF, Rowan, KM, Saito, H, Santos, MS, Saunders, CT, Serpa-Neto, A, Seymour, CW, Shankar-Hari, M, Stronach, LM, Turgeon, AF, Turner, AM, Van de Veerdonk, FL, Zarychanski, R, Green, C, Lewis, RJ, Angus, DC, McArthur, CJ, Berry, S, Derde, LPG, Gordon, AC, Webb, SA, Lawler, PR, Comm REMAP-CAP Investigators, Apollo - University of Cambridge Repository, Intensive Care Medicine, Université de Versailles Saint-Quentin-en-Yvelines - UFR Sciences de la santé Simone Veil (UVSQ Santé), Université de Versailles Saint-Quentin-en-Yvelines (UVSQ), Hôpital Raymond Poincaré [Garches], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP), Pittsburgh Foundation, PF, Amgen, Health Research Board, HRB: CTN 2014-012, Horizon 2020 Framework Programme, H2020: 101003589, Translational Breast Cancer Research Consortium, TBCRC, Canadian Institutes of Health Research, IRSC: 158584, Heart and Stroke Foundation of Canada, HSF, National Institute for Health and Care Research, NIHR, European Commission, EC, National Health and Medical Research Council, NHMRC: 1101719, APP194811, CS-2016-16-011, GNT2008447, RP-2015-06-18, Office of Health and Medical Research, OHMR, Health Research Council of New Zealand, HRC: 16/631, Eisai, Ministère des Affaires Sociales et de la Santé: PHRC-20-0147, Université Pierre et Marie Curie, UPMC, NIHR Imperial Biomedical Research Centre, BRC, Minderoo Foundation, Funding/Support : The Platform for European Preparedness Against (Re-) emerging Epidemics (PREPARE) consortium by the European Union, FP7-HEALTH-2013-INNOVATION-1 (#602525), the Rapid European COVID-19 Emergency Research response (RECOVER) consortium by the European Union’s Horizon 2020 research and innovation programme (#101003589), the Australian National Health and Medical Research Council (#APP1101719), the Australian Medical Research Future Fund (#APP2002132), the Health Research Council of New Zealand (#16/631), the Canadian Institutes of Health Research Strategy for Patient-Oriented Research Innovative Clinical Trials Program Grant (#158584) and the Canadian Institute of Health Research COVID-19 Rapid Research Funding (#447335), the UK National Institute for Health Research (NIHR) and the NIHR Imperial Biomedical Research Centre, the Health Research Board of Ireland (CTN 2014-012), the UPMC Learning While Doing Program, the Translational Breast Cancer Research Consortium, the French Ministry of Health (PHRC-20-0147), the Wellcome Trust Innovations Project (215522), the Minderoo Foundation, the EU Programme Emergency Support Instrument, the NHS Blood and Transplant Research and Development Programme, the Translational Breast Cancer Research Consortium, the NSW Office of Health and Medical Research, Amgen, Eisai, and the Pittsburgh Foundation. Dr Higgins is funded by an NHMRC Emerging Leadership Fellowship (GNT2008447). Dr McQuilten is funded by an NHMRC Emerging Leadership Fellowship (APP194811). Dr Gordon is funded by an NIHR Research Professorship (RP-2015-06-18) and Dr Shankar-Hari by an NIHR Clinician Scientist Fellowship (CS-2016-16-011). Dr Turgeon is the Chairholder of the Canada Research Chair in Critical Care Neurology and Trauma. Dr Lawler is supported by a career award from the Heart and Stroke Foundation of Canada., and European Project: 602525,EC:FP7:HEALTH,FP7-HEALTH-2013-INNOVATION-1,PREPARE(2014)
- Subjects
Adult ,Male ,corticosteroid ,[SDV]Life Sciences [q-bio] ,Critical Illness ,lnfectious Diseases and Global Health Radboud Institute for Molecular Life Sciences [Radboudumc 4] ,antiplatelet ,Lopinavir ,Adaptive platform trial randomized controlled trial intensive care, pneumonia COVID-19 antiplatelet immunoglobulin antiviral corticosteroid immune modulation anticoagulation ,All institutes and research themes of the Radboud University Medical Center ,Adrenal Cortex Hormones ,Humans ,anticoagulation ,intensive care, pneumonia ,COVID-19 Serotherapy ,Original Investigation ,Medicine(all) ,immune modulation ,Ritonavir ,SARS-CoV-2 ,COVID-19 ,Anticoagulants ,Bayes Theorem ,General Medicine ,Middle Aged ,antiviral ,Receptors, Interleukin-6 ,Adaptive platform trial ,randomized controlled trial ,Female ,Human medicine ,immunoglobulin ,Follow-Up Studies ,Hydroxychloroquine - Abstract
ImportanceThe longer-term effects of therapies for the treatment of critically ill patients with COVID-19 are unknown.ObjectiveTo determine the effect of multiple interventions for critically ill adults with COVID-19 on longer-term outcomes.Design, Setting, and ParticipantsPrespecified secondary analysis of an ongoing adaptive platform trial (REMAP-CAP) testing interventions within multiple therapeutic domains in which 4869 critically ill adult patients with COVID-19 were enrolled between March 9, 2020, and June 22, 2021, from 197 sites in 14 countries. The final 180-day follow-up was completed on March 2, 2022.InterventionsPatients were randomized to receive 1 or more interventions within 6 treatment domains: immune modulators (n = 2274), convalescent plasma (n = 2011), antiplatelet therapy (n = 1557), anticoagulation (n = 1033), antivirals (n = 726), and corticosteroids (n = 401).Main Outcomes and MeasuresThe main outcome was survival through day 180, analyzed using a bayesian piecewise exponential model. A hazard ratio (HR) less than 1 represented improved survival (superiority), while an HR greater than 1 represented worsened survival (harm); futility was represented by a relative improvement less than 20% in outcome, shown by an HR greater than 0.83.ResultsAmong 4869 randomized patients (mean age, 59.3 years; 1537 [32.1%] women), 4107 (84.3%) had known vital status and 2590 (63.1%) were alive at day 180. IL-6 receptor antagonists had a greater than 99.9% probability of improving 6-month survival (adjusted HR, 0.74 [95% credible interval {CrI}, 0.61-0.90]) and antiplatelet agents had a 95% probability of improving 6-month survival (adjusted HR, 0.85 [95% CrI, 0.71-1.03]) compared with the control, while the probability of trial-defined statistical futility (HR >0.83) was high for therapeutic anticoagulation (99.9%; HR, 1.13 [95% CrI, 0.93-1.42]), convalescent plasma (99.2%; HR, 0.99 [95% CrI, 0.86-1.14]), and lopinavir-ritonavir (96.6%; HR, 1.06 [95% CrI, 0.82-1.38]) and the probabilities of harm from hydroxychloroquine (96.9%; HR, 1.51 [95% CrI, 0.98-2.29]) and the combination of lopinavir-ritonavir and hydroxychloroquine (96.8%; HR, 1.61 [95% CrI, 0.97-2.67]) were high. The corticosteroid domain was stopped early prior to reaching a predefined statistical trigger; there was a 57.1% to 61.6% probability of improving 6-month survival across varying hydrocortisone dosing strategies.Conclusions and RelevanceAmong critically ill patients with COVID-19 randomized to receive 1 or more therapeutic interventions, treatment with an IL-6 receptor antagonist had a greater than 99.9% probability of improved 180-day mortality compared with patients randomized to the control, and treatment with an antiplatelet had a 95.0% probability of improved 180-day mortality compared with patients randomized to the control. Overall, when considered with previously reported short-term results, the findings indicate that initial in-hospital treatment effects were consistent for most therapies through 6 months.
- Published
- 2023
35. First release of Apertif imaging survey data
- Author
-
Adams, E. A. K., primary, Adebahr, B., additional, de Blok, W. J. G., additional, Dénes, H., additional, Hess, K. M., additional, van der Hulst, J. M., additional, Kutkin, A., additional, Lucero, D. M., additional, Morganti, R., additional, Moss, V. A., additional, Oosterloo, T. A., additional, Orrú, E., additional, Schulz, R., additional, van Amesfoort, A. S., additional, Berger, A., additional, Boersma, O. M., additional, Bouwhuis, M., additional, van den Brink, R., additional, van Cappellen, W. A., additional, Connor, L., additional, Coolen, A. H. W. M., additional, Damstra, S., additional, van Diepen, G. N. J., additional, Dijkema, T. J., additional, Ebbendorf, N., additional, Grange, Y. G., additional, de Goei, R., additional, Gunst, A. W., additional, Holties, H. A., additional, Hut, B., additional, Ivashina, M. V., additional, Józsa, G. I. G., additional, van Leeuwen, J., additional, Loose, G. M., additional, Maan, Y., additional, Mancini, M., additional, Mika, Á., additional, Mulder, H., additional, Norden, M. J., additional, Offringa, A. R., additional, Oostrum, L. C., additional, Pastor-Marazuela, I., additional, Pisano, D. J., additional, Ponomareva, A. A., additional, Romein, J. W., additional, Ruiter, M., additional, Schoenmakers, A. P., additional, van der Schuur, D., additional, Sluman, J. J., additional, Smits, R., additional, Stuurwold, K. J. C., additional, Verstappen, J., additional, Vilchez, N. P. E., additional, Vohl, D., additional, Wierenga, K. J., additional, Wijnholds, S. J., additional, Woestenburg, E. E. M., additional, Zanting, A. W., additional, and Ziemke, J., additional
- Published
- 2022
- Full Text
- View/download PDF
36. Acute and short-term effects of caloric restriction on metabolic profile and brain activation in obese, postmenopausal women
- Author
-
Jakobsdottir, S, van Nieuwpoort, I C, van Bunderen, C C, de Ruiter, M B, Twisk, J W R, Deijen, J B, Veltman, D J, and Drent, M L
- Published
- 2016
- Full Text
- View/download PDF
37. A power analysis for future clinical trials on the potential adverse effects of SSRIs on amygdala reactivity
- Author
-
Bottelier, M. A., Schrantee, A., van Wingen, G., Ruhé, H. G., de Ruiter, M. B., and Reneman, L.
- Published
- 2016
- Full Text
- View/download PDF
38. Effects of methylphenidate during emotional processing in amphetamine users: preliminary findings
- Author
-
Bottelier, M. A., Schouw, M. L. J., de Ruiter, M. B., Ruhe, H. G., Lindauer, R. J. L., and Reneman, L.
- Published
- 2015
- Full Text
- View/download PDF
39. The Apertif science verification campaign
- Author
-
Adebahr, B., primary, Berger, A., additional, Adams, E. A. K., additional, Hess, K. M., additional, de Blok, W. J. G., additional, Dénes, H., additional, Moss, V. A., additional, Schulz, R., additional, van der Hulst, J. M., additional, Connor, L., additional, Damstra, S., additional, Hut, B., additional, Ivashina, M. V., additional, Loose, G. M., additional, Maan, Y., additional, Mika, A., additional, Mulder, H., additional, Norden, M. J., additional, Oostrum, L. C., additional, Orrú, E., additional, Ruiter, M., additional, Smits, R., additional, van Cappellen, W. A., additional, van Leeuwen, J., additional, Vermaas, N. J., additional, Vohl, D., additional, and Ziemke, J., additional
- Published
- 2022
- Full Text
- View/download PDF
40. Het psychologische contract als dynamisch proces in complexe technologische contexten
- Author
-
Jacobs, RAF, Peters, P, De Ruiter, M, Blomme, RJ, RS-Research Program Learning and Innovation in Resilient systems (LIRS), and Department of Organisation
- Subjects
Technology ,Sociomateriality ,Dynamic processes ,Psychological contract - Abstract
Het psychologische contract is een managementconcept dat verklaart hoe veranderingen in en het al dan niet naleven van wederzijdse verplichtingen tussen werkgever en werknemer samenhangen met attitudes en gedragingen. Onderzoekers gaan veelal uit van causale, lineaire verbanden tussen een psychologisch contractbreuk en werknemersattituden en -gedragingen en maken gebruik van de sociale uitwisselingstheorie om reacties op psychologisch contractbreuk te verklaren. Steeds vaker wordt erkend dat dit perspectief moet worden aangevuld met andere theorieën en onderzoeksmethoden om zo de complexiteit en de dynamieken van het psychologische contract beter te begrijpen. Gezien het grotendeels uitblijven van onderzoek naar de rol van technologie, is er ook steeds meer vraag naar theorieën die het begrip van technologie in het psychologisch contractraamwerk vergroten. Dit is voornamelijk van belang in vluchtige, onzekere, complexe en ambigue arbeidscontexten. In deze conceptuele paper stellen we voor om de sociomaterialiteitstheorie als een aanvullende lens te gebruiken om meer inzicht te krijgen in de rol van technologie in de dynamiek van het psychologische contract. We vergelijken de traditionele en recentere psychologisch contractperspectieven met het sociomaterialiteitsperspectief en leggen uit waar deze lens een waardevolle bijdrage aan de literatuur kan leveren. We sluiten af met een kritische reflectie op dit perspectief en praktische aanbevelingen.
- Published
- 2021
41. Effects of desk-bike cycling on phonological working memory performance in adolescents with attention deficit hyperactivity disorder
- Author
-
Ruiter, M., Görlich, E., Loyens, S., Wong, J., Paas, F., Faculteit Sociale Wetenschappen, Educational and Developmental Psychology, and Faculteit Sociale Wetenschappen
- Subjects
education ,ADHD ,phonological working memory ,desk bikes ,adolescents ,active workstations ,Education - Abstract
We investigated the effects of active workstations on cognitive control functions in individuals diagnosed with Attention Deficit Hyperactivity Disorder (ADHD). In a fully counterbalanced randomized control design, we examined the effects of cycling on a desk bike on phonological working memory (WM) in 18 adolescents with ADHD. Adolescents performed a phonological WM test across two separate sessions during which they either cycled or not. It was hypothesized that participants would perform better on the WM task while cycling as compared to seated-rest. Results showed that total WM performance was not affected by desk-bike cycling. Exploratory analyses suggested that cycling during more difficult trials (i.e., high WM demands) is beneficial for WM performance. More research is needed to shed light on how task difficulty moderates the potential compensatory effect of desk-bike cycling on WM performance in adolescent ADHD participants.
- Published
- 2022
42. Avoiding blame in policy crises in different institutional settings
- Author
-
Ruiter, M. de and Kuipers, S.L.
- Subjects
Political Accountability ,Informal Institutions ,Blame Avoidance ,Institutional Theory ,Political Survival ,Crisis Analysis - Abstract
Policy crises often lead to “framing contests,” in which officeholders, opponents, media, and the public at large aim to interpret the crisis in question, explain its cause, attribute responsibility, and agree on ways to address harm caused. More often than not, these contests turn into blame games for the incumbent officeholder. Formal and informal institutional factors can shape blame avoidance options of officeholders, and influence the outcomes of these crisis-induced blame games in terms of blame escalation, policy responses, and political sanctions.First, formal institutions shape officeholders’ incentives for arguing that they are not responsible for the crisis or should not be punished for its occurrence. Studies in the field of welfare state retrenchment and ministerial resignations have analyzed the blame avoidance options of governments and the survival rates of officeholders in various institutional settings. These studies have provided evidence that institutional complexity and policy-making authority help explaining pathways of blame management. In single-party governments, the accountability chain is more clear and prime ministers have a stronger electoral incentive to sack failing and unpopular ministers. However, a more restrictive interpretation of formal ministerial responsibility for administrative or implementation failures, along with the delegation of policy execution to agencies at arm’s length, can work as a protective shield in blame games for the officeholders and reinforce policy inertia. Consociational systems with multiparty coalitions often show an opposite effect.Second, institutionalized norms, also known as “the way we do things around here,” affect blame avoidance behavior available to officeholders. Studies which have taken “cultural-institutional” approaches to accountability studies have shown that informal accountability actors, fora, and norms about appropriate behavior shape blame processes. Actors in consociational systems with multiparty coalitions often consider consensus-oriented and nonconfrontational behavior, such as attempts to appease the opposition with policy reparations, as more appropriate responses to blame than those in systems with more elite polarization. In addition, officeholders are increasingly held to account by actors who solely have an informal role in blame games, such as the media and interest groups. Therefore, the extent of mediatization and increased polarization plays a major role in how different political contexts “process” blame.Third, other relevant noninstitutional factors for blame avoidance behavior are important, such as the nature and timing of the crisis and involvement of other actors in the blame game. Issue salience and proximity affect the potential for blame escalations and the options for blame management by both office holders and their opponents. Prior reputation of incumbent politicians helps them to draw on leadership capital to deflect blame. If the timing of a blame game coincides with upcoming elections, blame is more likely to escalate and lead to political sanctions.To further understanding of the role of institutional factors in crisis-induced blames games, future research should focus on blame games where institutions themselves are questioned, contested, or in-flux.
- Published
- 2022
43. Sub-arcsecond imaging with the International LOFAR Telescope: II. Completion of the LOFAR Long-Baseline Calibrator Survey
- Author
-
Jackson, N., Badole, S., Morgan, J., Chhetri, R., Prūsis, K., Nikolajevs, A., Morabito, L., Brentjens, M., Sweijen, F., Iacobelli, M., Orrù, E., Sluman, J., Blaauw, R., Mulder, H., van Dijk, P., Mooney, S., Deller, A., Moldon, J., Callingham, J.R., Harwood, J., Hardcastle, M., Heald, G., Drabent, A., Mckean, J.P., Asgekar, A., Avruch, I.M., Bentum, M.J., Bonafede, A., Brouw, W.N., Brüggen, M., Butcher, H.R., Ciardi, B., Coolen, A., Corstanje, A., Damstra, S., Duscha, S., Eislöffel, J., Falcke, H., Garrett, M., De Gasperin, F., Griessmeier, J.M., Gunst, A.W., van Haarlem, M.P., Hoeft, M., van der Horst, A.J., Jütte, E., Koopmans, L.V.E., Krankowski, A., Maat, P., Mann, G., Miley, G.K., Nelles, A., Norden, M., Paas, M., Pandey, V.N., Pandey-Pommier, M., Pizzo, R.F., Reich, W., Rothkaehl, H., Rowlinson, A., Ruiter, M., Shulevski, A., Schwarz, D.J., Smirnov, O., Tagger, M., Vocks, C., van Weeren, R.J., Wijers, R., Wucknitz, O., Zarka, P., Zensus, J.A., Zucca, P., Jackson, N., Badole, S., Morgan, J., Chhetri, R., Prūsis, K., Nikolajevs, A., Morabito, L., Brentjens, M., Sweijen, F., Iacobelli, M., Orrù, E., Sluman, J., Blaauw, R., Mulder, H., van Dijk, P., Mooney, S., Deller, A., Moldon, J., Callingham, J.R., Harwood, J., Hardcastle, M., Heald, G., Drabent, A., Mckean, J.P., Asgekar, A., Avruch, I.M., Bentum, M.J., Bonafede, A., Brouw, W.N., Brüggen, M., Butcher, H.R., Ciardi, B., Coolen, A., Corstanje, A., Damstra, S., Duscha, S., Eislöffel, J., Falcke, H., Garrett, M., De Gasperin, F., Griessmeier, J.M., Gunst, A.W., van Haarlem, M.P., Hoeft, M., van der Horst, A.J., Jütte, E., Koopmans, L.V.E., Krankowski, A., Maat, P., Mann, G., Miley, G.K., Nelles, A., Norden, M., Paas, M., Pandey, V.N., Pandey-Pommier, M., Pizzo, R.F., Reich, W., Rothkaehl, H., Rowlinson, A., Ruiter, M., Shulevski, A., Schwarz, D.J., Smirnov, O., Tagger, M., Vocks, C., van Weeren, R.J., Wijers, R., Wucknitz, O., Zarka, P., Zensus, J.A., and Zucca, P.
- Abstract
The Low-Frequency Array (LOFAR) Long-Baseline Calibrator Survey (LBCS) was conducted between 2014 and 2019 in order to obtain a set of suitable calibrators for the LOFAR array. In this paper, we present the complete survey, building on the preliminary analysis published in 2016 which covered approximately half the survey area. The final catalogue consists of 30 006 observations of 24 713 sources in the northern sky, selected for a combination of high low-frequency radio flux density and flat spectral index using existing surveys (WENSS, NVSS, VLSS, and MSSS). Approximately one calibrator per square degree, suitable for calibration of ≥200 km baselines is identified by the detection of compact flux density, for declinations north of 30° and away from the Galactic plane, with a considerably lower density south of this point due to relative difficulty in selecting flat-spectrum candidate sources in this area of the sky. The catalogue contains indicators of degree of correlated flux on baselines between the Dutch core and each of the international stations, involving a maximum baseline length of nearly 2000 km, for all of the observations. Use of the VLBA calibrator list, together with statistical arguments by comparison with flux densities from lower-resolution catalogues, allow us to establish a rough flux density scale for the LBCS observations, so that LBCS statistics can be used to estimate compact flux densities on scales between 300 mas and 2′, for sources observed in the survey. The survey is used to estimate the phase coherence time of the ionosphere for the LOFAR international baselines, with median phase coherence times of about 2 min varying by a few tens of percent between the shortest and longest baselines. The LBCS can be used to assess the structures of point sources in lower-resolution surveys, with significant reductions in the degree of coherence in these sources on scales between 2′ and 300 mas. The LBCS survey sources show a greater incidence of
- Published
- 2022
44. Effects of Desk-Bike Cycling on Phonological Working Memory Performance in Adolescents With Attention Deficit Hyperactivity Disorder
- Author
-
Faculteit Sociale Wetenschappen, Ruiter, M., Görlich, E., Loyens, S., Wong, J., Paas, F., Faculteit Sociale Wetenschappen, Ruiter, M., Görlich, E., Loyens, S., Wong, J., and Paas, F.
- Published
- 2022
45. Modelling the cost and benefits of adaptation. A targeted review on integrated assessment models with a special focus on adaptation modelling
- Author
-
Kondrup, C., Mercogliano, P., Bosello, F., Mysiak, J., Scoccimarro, E., Rizzo, A., Ebrey, R., de Ruiter, M., Jeuken, A., Watkiss, P., Schwarze, Reimund, Oberpriller, Q., Peter, M., Füssler, J., Kondrup, C., Mercogliano, P., Bosello, F., Mysiak, J., Scoccimarro, E., Rizzo, A., Ebrey, R., de Ruiter, M., Jeuken, A., Watkiss, P., Schwarze, Reimund, Oberpriller, Q., Peter, M., and Füssler, J.
- Abstract
This paper gives a targeted review on Integrated Assessment Models (IAMs) with a focus on damage functions and adaptation modelling.
- Published
- 2022
46. The challenge of unprecedented floods and droughts in risk management
- Author
-
Kreibich, H. Van Loon, A. F. Schröter, K. Ward, P. J. Mazzoleni, M. Sairam, N. Abeshu, G. W. Agafonova, S. AghaKouchak, A. Aksoy, H. Alvarez-Garreton, C. Aznar, B. Balkhi, L. Barendrecht, M. H. Biancamaria, S. Bos-Burgering, L. Bradley, C. Budiyono, Y. Buytaert, W. Capewell, L. Carlson, H. Cavus, Y. Couasnon, A. Coxon, G. Daliakopoulos, I. de Ruiter, M. C. Delus, C. Erfurt, M. Esposito, G. François, D. Frappart, F. Freer, J. Frolova, N. Gain, A. K. Grillakis, M. Grima, J. O. Guzmán, D. A. Huning, L. S. Ionita, M. Kharlamov, M. Khoi, D. N. Kieboom, N. Kireeva, M. Koutroulis, A. Lavado-Casimiro, W. Li, H. Y. Llasat, M. C. Macdonald, D. Mård, J. Mathew-Richards, H. McKenzie, A. Mejia, A. Mendiondo, E. M. Mens, M. Mobini, S. Mohor, G. S. Nagavciuc, V. Ngo-Duc, T. Thao Nguyen Huynh, T. Nhi, P. T. T. Petrucci, O. Nguyen, H. Q. Quintana-Seguí, P. Razavi, S. Ridolfi, E. Riegel, J. Sadik, M. S. Savelli, E. Sazonov, A. Sharma, S. Sörensen, J. Arguello Souza, F. A. Stahl, K. Steinhausen, M. Stoelzle, M. Szalińska, W. Tang, Q. Tian, F. Tokarczyk, T. Tovar, C. Tran, T. V. T. Van Huijgevoort, M. H. J. van Vliet, M. T. H. Vorogushyn, S. Wagener, T. Wang, Y. Wendt, D. E. Wickham, E. Yang, L. Zambrano-Bigiarini, M. Blöschl, G. Di Baldassarre, G. and Kreibich, H. Van Loon, A. F. Schröter, K. Ward, P. J. Mazzoleni, M. Sairam, N. Abeshu, G. W. Agafonova, S. AghaKouchak, A. Aksoy, H. Alvarez-Garreton, C. Aznar, B. Balkhi, L. Barendrecht, M. H. Biancamaria, S. Bos-Burgering, L. Bradley, C. Budiyono, Y. Buytaert, W. Capewell, L. Carlson, H. Cavus, Y. Couasnon, A. Coxon, G. Daliakopoulos, I. de Ruiter, M. C. Delus, C. Erfurt, M. Esposito, G. François, D. Frappart, F. Freer, J. Frolova, N. Gain, A. K. Grillakis, M. Grima, J. O. Guzmán, D. A. Huning, L. S. Ionita, M. Kharlamov, M. Khoi, D. N. Kieboom, N. Kireeva, M. Koutroulis, A. Lavado-Casimiro, W. Li, H. Y. Llasat, M. C. Macdonald, D. Mård, J. Mathew-Richards, H. McKenzie, A. Mejia, A. Mendiondo, E. M. Mens, M. Mobini, S. Mohor, G. S. Nagavciuc, V. Ngo-Duc, T. Thao Nguyen Huynh, T. Nhi, P. T. T. Petrucci, O. Nguyen, H. Q. Quintana-Seguí, P. Razavi, S. Ridolfi, E. Riegel, J. Sadik, M. S. Savelli, E. Sazonov, A. Sharma, S. Sörensen, J. Arguello Souza, F. A. Stahl, K. Steinhausen, M. Stoelzle, M. Szalińska, W. Tang, Q. Tian, F. Tokarczyk, T. Tovar, C. Tran, T. V. T. Van Huijgevoort, M. H. J. van Vliet, M. T. H. Vorogushyn, S. Wagener, T. Wang, Y. Wendt, D. E. Wickham, E. Yang, L. Zambrano-Bigiarini, M. Blöschl, G. Di Baldassarre, G.
- Abstract
Risk management has reduced vulnerability to floods and droughts globally1,2, yet their impacts are still increasing3. An improved understanding of the causes of changing impacts is therefore needed, but has been hampered by a lack of empirical data4,5. On the basis of a global dataset of 45 pairs of events that occurred within the same area, we show that risk management generally reduces the impacts of floods and droughts but faces difficulties in reducing the impacts of unprecedented events of a magnitude not previously experienced. If the second event was much more hazardous than the first, its impact was almost always higher. This is because management was not designed to deal with such extreme events: for example, they exceeded the design levels of levees and reservoirs. In two success stories, the impact of the second, more hazardous, event was lower, as a result of improved risk management governance and high investment in integrated management. The observed difficulty of managing unprecedented events is alarming, given that more extreme hydrological events are projected owing to climate change3.
- Published
- 2022
- Full Text
- View/download PDF
47. Effect of physical exercise on cognitive function after chemotherapy in patients with breast cancer:a randomized controlled trial (PAM study)
- Author
-
Koevoets, E. W., Schagen, S. B., de Ruiter, M. B., Geerlings, M. I., Witlox, L., van der Wall, E., Stuiver, M. M., Sonke, G. S., Velthuis, M. J., Jobsen, J. J., Menke-Pluijmers, M. B.E., Göker, E., van der Pol, C. C., Bos, M. E.M.M., Tick, L. W., van Holsteijn, N. A., van der Palen, J., May, A. M., Monninkhof, E. M., Koevoets, E. W., Schagen, S. B., de Ruiter, M. B., Geerlings, M. I., Witlox, L., van der Wall, E., Stuiver, M. M., Sonke, G. S., Velthuis, M. J., Jobsen, J. J., Menke-Pluijmers, M. B.E., Göker, E., van der Pol, C. C., Bos, M. E.M.M., Tick, L. W., van Holsteijn, N. A., van der Palen, J., May, A. M., and Monninkhof, E. M.
- Abstract
Background: Up to 60% of breast cancer patients treated with chemotherapy is confronted with cognitive problems, which can have a significant impact on daily activities and quality of life (QoL). We investigated whether exercise training improves cognition in chemotherapy-exposed breast cancer patients 2–4 years after diagnosis. Methods: Chemotherapy-exposed breast cancer patients, with both self-reported cognitive problems and lower than expected performance on neuropsychological tests, were randomized to an exercise or control group. The 6-month exercise intervention consisted of supervised aerobic and strength training (2 h/week), and Nordic/power walking (2 h/week). Our primary outcome was memory functioning (Hopkins Verbal Learning Test-Revised; HVLT-R). Secondary outcomes included online neuropsychological tests (Amsterdam Cognition Scan; ACS), self-reported cognition (MD Anderson Symptom Inventory for multiple myeloma; MDASI-MM), physical fitness (relative maximum oxygen uptake; VO2peak), fatigue (Multidimensional Fatigue Inventory), QoL (European Organisation for Research and Treatment of Cancer Quality of Life Questionnaire; EORTC QLQ C-30), depression (Patient Health Questionnaire-9, Hospital Anxiety and Depression Scale; HADS), and anxiety (HADS). HVLT-R total recall was analyzed with a Fisher exact test for clinically relevant improvement (≥ 5 words). Other outcomes were analyzed using multiple regression analyses adjusted for baseline and stratification factors. Results: We randomized 181 patients to the exercise (n = 91) or control group (n = 90). Two-third of the patients attended ≥ 80% of the exercise sessions, and physical fitness significantly improved compared to control patients (B VO2peak 1.4 ml/min/kg, 95%CI:0.6;2.2). No difference in favor of the intervention group was seen on the primary outcome. Significant beneficial intervention effects were found for self-reported cognitive functioning [MDASI
- Published
- 2022
48. The Apertif science verification campaign: Characteristics of polarised radio sources
- Author
-
Ministerio de Ciencia e Innovación (España), European Research Council, German Research Foundation, Adebahr, B., Berger, A., Adams, E. A. K., Hess, Kelley M., de Blok, W. J. G., Dénes, H., Moss, V. A., Schulz, R., van der Hulst, J. M., Connor, L., Damstra, S., Hut, B., Ivashina, M. V., Loose, G. M., Maan, Y., Mika, A., Mulder, H., Norden, M. J., Oostrum, L. C., Orrú, E., Ruiter, M., Smits, R., van Cappellen, W. A., van Leeuwen, J., Vermaas, N. J., Voh, D. ., Ziemke, J, Ministerio de Ciencia e Innovación (España), European Research Council, German Research Foundation, Adebahr, B., Berger, A., Adams, E. A. K., Hess, Kelley M., de Blok, W. J. G., Dénes, H., Moss, V. A., Schulz, R., van der Hulst, J. M., Connor, L., Damstra, S., Hut, B., Ivashina, M. V., Loose, G. M., Maan, Y., Mika, A., Mulder, H., Norden, M. J., Oostrum, L. C., Orrú, E., Ruiter, M., Smits, R., van Cappellen, W. A., van Leeuwen, J., Vermaas, N. J., Voh, D. ., and Ziemke, J
- Abstract
Context. The characteristics of the polarised radio sky are a key ingredient in constraining evolutionary models of magnetic fields in the Universe and their role in feedback processes. The origin of the polarised emission and the characteristics of the intergalactic medium on the line of sight can be investigated using large samples of polarised sources. Ancillary infrared (IR) and optical data can be used to study the nature of the emitting objects. Aims. We analyse five early science datasets from the APERture Tile in Focus (Apertif) phased array feed system to verify the polarisation capabilities of Apertif in view of future larger data releases. We aim to characterise the source population of the polarised sky in the L-Band using polarised source information in combination with IR and optical data. Methods. We use automatic routines to generate full field-of-view Q- and U-cubes and perform rotation measure (RM)-Synthesis, source finding, and cross-matching with published radio, optical, and IR data to generate polarised source catalogues. All sources were inspected individually by eye for verification of their IR and optical counterparts. Spectral energy distribution (SED)-fitting routines were used to determine photometric redshifts, star-formation rates, and galaxy masses. IR colour information was used to classify sources as active galactic nuclei (AGN) or star-forming-dominated and early- or late-type. Results. We surveyed an area of 56 deg2 and detected 1357 polarised source components in 1170 sources. The fraction of polarised sources is 10.57% with a median fractional polarisation of 4.70 ± 0.14%. We confirmed the reliability of the Apertif measurements by comparing them with polarised cross-identified NVSS sources. Average RMs of the individual fields lie within the error of the best Milky Way foreground measurements. All of our polarised sources were found to be dominated by AGN activity in the radio regime with most of them being radio-loud (79%) and
- Published
- 2022
49. A dual-beam analog beamformer for LOFAR 2.0 enabling simultaneous space weather and radio astronomy observations
- Author
-
Ruiter, M., primary, Kruger, P., additional, Harison, S.R., additional, Bosse, S., additional, Barth, S., additional, da Silva, B., additional, and Taffourreau, C., additional
- Published
- 2022
- Full Text
- View/download PDF
50. Sub-arcsecond imaging with the International LOFAR Telescope
- Author
-
Morabito, L. K., Jackson, N. J., Mooney, S., Sweijen, F., Badole, S., Kukreti, P., Venkattu, D., Groeneveld, C., Kappes, A., Bonnassieux, E., Drabent, A., Iacobelli, M., Croston, J. H., Best, P. N., Bondi, M., Callingham, J. R., Conway, J. E., Deller, A. T., Hardcastle, M. J., McKean, J. P., Miley, G. K., Moldon, J., Röttgering, H. J. A., Tasse, C., Shimwell, T. W., van Weeren, R. J., Anderson, J. M., Asgekar, A., Avruch, I. M., van Bemmel, I. M., Bentum, M. J., Bonafede, A., Brouw, W. N., Butcher, H. R., Ciardi, B., Corstanje, A., Coolen, A., Damstra, S., de Gasperin, F., Duscha, S., Eislöffel, J., Engels, D., Falcke, H., Garrett, M. A., Griessmeier, J., Gunst, A. W., van Haarlem, M. P., Hoeft, M., van der Horst, A. J., Jütte, E., Kadler, M., Koopmans, L. V. E., Krankowski, A., Mann, G., Nelles, A., Oonk, J. B. R., Orru, E., Paas, H., Pandey, V. N., Pizzo, R. F., Pandey-Pommier, M., Reich, W., Rothkaehl, H., Ruiter, M., Schwarz, D. J., Shulevski, A., Soida, M., Tagger, M., Vocks, C., Wijers, R. A. M. J., Wijnholds, S. J., Wucknitz, O., Zarka, P., and Zucca, P.
- Subjects
ddc:520 - Abstract
Astronomy and astrophysics 658, A1 (2022). doi:10.1051/0004-6361/202140649, [abridged] The International LOFAR Telescope is an interferometer with stations spread across Europe. With baselines of up to ~2,000 km, LOFAR has the unique capability of achieving sub-arcsecond resolution at frequencies below 200 MHz, although this is technically and logistically challenging. Here we present a calibration strategy that builds on previous high-resolution work with LOFAR. We give an overview of the calibration strategy and discuss the special challenges inherent to enacting high-resolution imaging with LOFAR, and describe the pipeline, which is publicly available, in detail. We demonstrate the calibration strategy by using the pipeline on P205+55, a typical LOFAR Two-metre Sky Survey (LoTSS) pointing. We perform in-field delay calibration, solution referencing to other calibrators, self-calibration, and imaging of example directions of interest in the field. For this specific field and these ionospheric conditions, dispersive delay solutions can be transferred between calibrators up to ~1.5 degrees away, while phase solution transferral works well over 1 degree. We demonstrate a check of the astrometry and flux density scale. Imaging in 17 directions, the restoring beam is typically 0.3' x 0.2' although this varies slightly over the entire 5 square degree field of view. We achieve ~80 to 300 $\mu$Jy/bm image rms noise, which is dependent on the distance from the phase centre; typical values are ~90 $\mu$Jy/bm for the 8 hour observation with 48 MHz of bandwidth. Seventy percent of processed sources are detected, and from this we estimate that we should be able to image ~900 sources per LoTSS pointing. This equates to ~3 million sources in the northern sky, which LoTSS will entirely cover in the next several years. Future optimisation of the calibration strategy for efficient post-processing of LoTSS at high resolution (LoTSS-HR) makes this estimate a lower limit., Published by EDP Sciences, Les Ulis
- Published
- 2022
Catalog
Discovery Service for Jio Institute Digital Library
For full access to our library's resources, please sign in.