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1. Probabilistic modeling of noise transfer characteristics in digital circuits

Author: J. Schleifer, T. Coenen, A. Elkammar, and T. G. Noll
Subjects: Engineering (General). Civil engineering (General), TA1-2040
Abstract: Device scaling, the driving force of CMOS technology, led to continuous decrease in the energy level representing logic states. The resulting small noise margins in combination with increasing problems regarding the supply voltage stability and process variability creates a design conflict between efficiency and reliability. This conflict is expected to rise more in future technologies. Current research approaches on fault-tolerance architectures and countermeasures at circuit level, unfortunately, cause a significant area and energy penalty without guaranteeing absence of errors. To overcome this problem, it seems to be attractive to tolerate bit errors at circuit level and employ error handling methods at higher system levels. To do this, an estimate of the bit error rate (BER) at circuit level is necessary. Due to the size of the circuits, Monte Carlo simulation suffers from impractical runtimes. Therefore the needed modeling scheme is proposed. The model allows a probabilistic estimation of error rates at circuit level taking into account statistical effects ranging from supply noise and electromagnetic coupling to process variability within reasonable runtimes.
Published: 2011
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2. A search for pulsars in subdwarf B binary systems and discovery of giant-pulse emitting PSR J0533-4524

Author: J. van Leeuwen, L. C. Oostrum, T. Coenen, C. H. Ishwara-Chandra, Yogesh Maan, High Energy Astrophys. & Astropart. Phys (API, FNWI), API Other Research (FNWI), and Faculty of Science
Subjects: Physics, High Energy Astrophysical Phenomena (astro-ph.HE), Giant Metrewave Radio Telescope, 010308 nuclear & particles physics, Astrophysics::High Energy Astrophysical Phenomena, White dwarf, FOS: Physical sciences, Astronomy and Astrophysics, Astrophysics, Astrophysics::Cosmology and Extragalactic Astrophysics, Light curve, 01 natural sciences, Subdwarf, Radio telescope, Neutron star, Pulsar, 13. Climate action, Space and Planetary Science, Millisecond pulsar, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics
Abstract: Binary millisecond pulsars (MSPs) provide several opportunities for research of fundamental physics. However, finding them can be challenging. Several subdwarf B (sdB) binary systems with possible neutron star companions have been identified, allowing us to perform a targeted search for MSPs within these systems. Six sdBs with companions in the neutron star mass range, as determined from their optical light curves, were observed with the Green Bank and Westerbork radio telescopes. The data were searched for periodic signals as well as single pulses. No radio pulsations from sdB systems were detected, down to an average sensitivity limit of 0.11 mJy. We did, however, discover a pulsar in the field of sdB HE0532-4503. Follow-up observations with the Giant Metrewave Radio Telescope showed that this pulsar, J0533-4524, is not spatially coincident with the sdB system. The pulsar has a relatively low magnetic field but still emits giant pulses. We place an upper limit of three to the number of radio pulsars in the six sdB systems. The non-detections may be explained by a combination of the MSP beaming fraction, luminosity, and a recycling fraction, 12 pages, 8 figures. Accepted for publication in MNRAS
Published: 2020

3. RFI flagging implications for short-duration transients

Author: A. J. van der Horst, D. Carbone, Casey J. Law, Jochen Eislöffel, Jean-Mathias Grießmeier, Ralph A. M. J. Wijers, John D. Swinbank, Martin Bell, Adam Stewart, Y. Cendes, T. Coenen, Folkert Huizinga, M. Pietka, Michael W. Wise, J. W. Broderick, P. Zarka, Peeyush Prasad, Stephane Corbel, Rob Fender, M. Kuniyoshi, Peter G. Jonker, Ben Stappers, Gijs Molenaar, Antonia Rowlinson, A. Alexov, Tim D. Staley, Michael Kramer, High Energy Astrophys. & Astropart. Phys (API, FNWI), API Other Research (FNWI), Faculty of Science, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), CSIRO Astronomy and Space Science, Commonwealth Scientific and Industrial Research Organisation [Canberra] (CSIRO), Netherlands Institute for Radio Astronomy (ASTRON), Oxford Astrophysics, University of Oxford, Sydney Institute for Astronomy (SIfA), The University of Sydney, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Thüringer Landessternwarte Tautenburg (TLS), Department of Physics [Oxford], Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], Max-Planck-Institut für Radioastronomie (MPIFR), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), University of Oxford [Oxford], Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Radboud university [Nijmegen], Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Jodrell Bank Centre for Astrophysics, and PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS)
Subjects: Data stream, Computer science, Astronomy, FOS: Physical sciences, RFI, Automated flagging, 010501 environmental sciences, Low frequency, 01 natural sciences, Signal, transient rates, Electromagnetic interference, Radio telescope, 0103 physical sciences, radio transients, Transient rates, Instrumentation and Methods for Astrophysics (astro-ph.IM), 010303 astronomy & astrophysics, 0105 earth and related environmental sciences, Remote sensing, Flagging, Astrophysics::Instrumentation and Methods for Astrophysics, food and beverages, Astronomy and Astrophysics, LOFAR, Radio Frequency Interference, Computer Science Applications, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Radio transients, transient rate limits, Space and Planetary Science, Transient rate limits, Transient (oscillation), Astrophysics - Instrumentation and Methods for Astrophysics
Abstract: With their wide fields of view and often relatively long coverage of any position in the sky in imaging survey mode, modern radio telescopes provide a data stream that is naturally suited to searching for rare transients. However, Radio Frequency Interference (RFI) can show up in the data stream in similar ways to such transients, and thus the normal pre-treatment of filtering RFI (flagging) may also remove astrophysical transients from the data stream before imaging. In this paper we investigate how standard flagging affects the detectability of such transients by examining the case of transient detection in an observing mode used for Low Frequency Array (LOFAR; \citep{LOFAR}) surveys. We quantify the fluence range of transients that would be detected, and the reduction of their SNR due to partial flagging. We find that transients with a duration close to the integration sampling time, as well as bright transients with durations on the order of tens of seconds, are completely flagged. For longer transients on the order of several tens of seconds to minutes, the flagging effects are not as severe, although part of the signal is lost. For these transients, we present a modified flagging strategy which mitigates the effect of flagging on transient signals. We also present a script which uses the differences between the two strategies, and known differences between transient RFI and astrophysical transients, to notify the observer when a potential transient is in the data stream., 31 pages, 6 figures, accepted for publication in Astronomy and Computing
Published: 2018
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4. LOFAR radio search for single and periodic pulses from M 31

Author: S. Sanidas, Evan Keane, Liam Connor, V. I. Kondratiev, Daniele Michilli, T. Coenen, Klim Mikhailov, Joeri van Leeuwen, High Energy Astrophys. & Astropart. Phys (API, FNWI), and Faculty of Science
Subjects: 010504 meteorology & atmospheric sciences, Andromeda Galaxy, Astrophysics::High Energy Astrophysical Phenomena, Population, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, 01 natural sciences, Radio telescope, Pulsar, 0103 physical sciences, Astrophysics::Solar and Stellar Astrophysics, education, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, education.field_of_study, Crab Pulsar, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy and Astrophysics, LOFAR, Galaxy, Neutron star, Space and Planetary Science, Astrophysics::Earth and Planetary Astrophysics, Astrophysics - High Energy Astrophysical Phenomena
Abstract: Bright, short radio bursts are emitted by sources at a large range of distances: from the nearby Crab pulsar to remote Fast Radio Bursts (FRBs). FRBs are likely to originate from distant neutron stars, but our knowledge of the radio pulsar population has been limited to the Galaxy and the Magellanic Clouds. In an attempt to increase our understanding of extragalactic pulsar populations, and its giant-pulse emission, we employed the low-frequency radio telescope LOFAR to search the Andromeda Galaxy (M31) for radio bursts emitted by young, Crab-like pulsars. For direct comparison we also present a LOFAR study on the low-frequency giant pulses from the Crab pulsar; their fluence distribution follows a power law with slope 3.04(3). A number of candidate signals were detected from M31 but none proved persistent. FRBs are sometimes thought of as Crab-like pulsars with exceedingly bright giant pulses -- given our sensitivity, we can rule out that M31 hosts pulsars more than an order of magnitude brighter than the Crab pulsar, assuming their pulse scattering follows that of the known FRBs., Accepted for publication in A&A. 6 pages with 4 nice figures
Published: 2020
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5. Conclusions from the HIV in Europe Copenhagen 2012 Conference and ways forward: working together for optimal HIV testing and earlier care

Author: Dorthe Raben, Jens D Lundgren, N. Dedes, Ann Sullivan, J. B. F. De Wit, Jeffrey V. Lazarus, Valerie Delpech, and T Coenen
Subjects: Gerontology, medicine.medical_specialty, genetic structures, business.industry, Health Policy, Human immunodeficiency virus (HIV), virus diseases, Hiv testing, medicine.disease_cause, Infectious Diseases, Family medicine, Medicine, Pharmacology (medical), business
Abstract: The objective of this article is to set the scene for this supplement by presenting and discussing the overall outcomes of the HIV in Europe Copenhagen 2012 Conference and how the HIV in Europe initiative intends to further address challenges and themes raised during the conference.
Published: 2013
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6. Free Speech and the Law of Evidence

Author: Dan T. Coenen
Subjects: Judicial Role, Law, media_common.quotation_subject, Jurisprudence, Political science, Criminal law, Relevance (law), Doctrine, Constitutional review, Constitutional law, media_common, Supreme court
Abstract: To what extent does the First Amendment limit the ability of prosecutors to offer evidence of a defendant’s past protected speech? As it turns out, the Supreme Court has touched on this question in only a handful of rulings, each of which it crafted to target only the distinctive facts of the case at hand. Many lower courts, however, have distilled from these decisions a sweeping, admissibility-favoring constitutional rule. According to that rule, the First Amendment imposes no limit on prosecutorial use of past-speech evidence—no matter how prejudicial—so long as it meets the minimum standard of evidentiary relevance. This approach is misguided. To begin with, it finds no support in the Court’s past decisions, which in fact favor, rather than disfavor, a meaningful judicial role in evaluating the use of past-speech evidence. Even more important, a hands-off stance clashes with long-honored free-speech-supporting constitutional policies. As a result, this Article calls for judicial recognition of a new set of First Amendment protections that operate whenever challenged past-speech evidence involves expression on a matter of public concern. This build-out of existing doctrine comports with the Court’s specialized protection of public-concern speech in a wide variety of settings. It also gains momentum from the Court’s jurisprudence regarding constitutional review of generally applicable laws—in this case, the generally applicable law of evidence. On close examination, the doctrine in this field, and the policies that underlie it, provide strong support for an approach that imposes both procedural and substantive constraints on the use of public-concern speech to secure criminal convictions. Such an approach is offered here.
Published: 2017
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7. The case for indicator condition-guided HIV screening

Author: Jeffrey V. Lazarus, Valerie Delpech, Dorthe Raben, T Coenen, M Hoekstra, and Jens D Lundgren
Subjects: medicine.medical_specialty, Pediatrics, business.industry, Health Policy, Human immunodeficiency virus (HIV), virus diseases, HIV screening, Hiv testing, medicine.disease, European region, medicine.disease_cause, World health, Late presentation, Infectious Diseases, Hiv test, Acquired immunodeficiency syndrome (AIDS), Family medicine, medicine, Pharmacology (medical), business
Abstract: One-half of the estimated 2.5 million people who now live with HIV in the World Health Organization (WHO) European Region are still diagnosed late. A central question is which clinical scenarios should trigger an HIV test recommendation in order to avoid late presentation. Drawing on the work of the HIV Indicator Diseases across Europe Study (HIDES), new guidance brings together in one place a list of the conditions that should result in an HIV screening recommendation.
Published: 2013
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8. Synchronous X-ray and Radio Mode Switches: A Rapid Global Transformation of the Pulsar Magnetosphere

Author: Y. Tang, Anna M. M. Scaife, Steve Rawlings, Aris Karastergiou, Michael W. Wise, Harvey Butcher, B. Ciardi, S. Duscha, V. N. Pandey, Gianni Bernardi, John McKean, Charlotte Sobey, Emanuela Orrú, Chiara Ferrari, M. Kuniyoshi, H. Munk, Marcus Brüggen, Michael Kramer, Cyril Tasse, J. W. Broderick, E. de Geus, Ashish Asgekar, Jason W. T. Hessels, F. de Gasperin, Matthias Hoeft, George Heald, L. Kuiper, A. P. Schoenmakers, P. Maat, R. H. van de Brink, Sera Markoff, Dipanjan Mitra, Philip Best, G. Wright, Ralph A. M. J. Wijers, J. de Plaa, Heino Falcke, V. I. Kondratiev, Rahul Basu, A. Noutsos, T. Coenen, Benjamin Stappers, Michel Tagger, Frank Breitling, Giulia Macario, Rob Fender, Rene C. Vermeulen, Michael R. Bell, F. Batejat, A. Alexov, Marco Iacobelli, H. Paas, Sarod Yatawatta, Patrick Weltevrede, Tim Hassall, R. J. van Weeren, W. Reich, M. Pilia, Laura Birzan, W. Hermsen, Evan Keane, Aleksandar Shulevski, Mark J. Bentum, M. Serylak, Martin Bell, Annalisa Bonafede, J. van Leeuwen, A. Horneffer, Jochen Eislöffel, Maaijke Mevius, H. J. A. Röttgering, A. G. Polatidis, R. Morganti, I. M. Avruch, S. ter Veen, A. W. Gunst, Olaf Wucknitz, Matthias Steinmetz, M. Pandey-Pommier, K. Zagkouris, J. Sluman, Roberto Pizzo, Jean-Mathias Grießmeier, G. Kuper, Philippe Zarka, Joanna M. Rankin, M. A. Garrett, James Miller-Jones, Wilfred Frieswijk, Hermsen, W., Hessels, J.W.T., Kuiper, L., Van Leeuwen, J., Mitra, D., De Plaa, J., Rankin, J.M., Stappers, B.W., Wright, G.A.E., Basu, R., Alexov, A., Coenen, T., Grießmeier, J.-M., Hassall, T.E., Karastergiou, A., Keane, E., Kondratiev, V.I., Kramer, M., Kuniyoshi, M., Noutsos, A., Serylak, M., Pilia, M., Sobey, C., Weltevrede, P., Zagkouris, K., Asgekar, A., Avruch, I.M., Batejat, F., Bell, M.E., Bell, M.R., Bentum, M.J., Bernardi, G., Best, P., Bîrzan, L., Bonafede, A., Breitling, F., Broderick, J., Brüggen, M., Butcher, H.R., Ciardi, B., Duscha, S., Eislöffel, J., Falcke, H., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M.A., De Gasperin, F., De Geus, E., Gunst, A.W., Heald, G., Hoeft, M., Horneffer, A., Iacobelli, M., Kuper, G., Maat, P., Macario, G., Markoff, S., McKean, J.P., Mevius, M., Miller-Jones, J.C.A., Morganti, R., Munk, H., Orrú, E., Paas, H., Pandey-Pommier, M., Pandey, V.N., Pizzo, R., Polatidis, A.G., Rawlings, S., Reich, W., Röttgering, H., Scaife, A.M.M., Schoenmakers, A., Shulevski, A., Sluman, J., Steinmetz, M., Tagger, M., Tang, Y., Tasse, C., Ter Veen, S., Vermeulen, R., Van De Brink, R.H., Van Weeren, R.J., Wijers, R.A.M.J., Wise, M.W., Wucknitz, O., Yatawatta, S., Zarka, P., SRON Netherlands Institute for Space Research (SRON), University of Amsterdam [Amsterdam] (UvA), National Centre for Radio Astrophysics [Pune] (NCRA), Tata Institute for Fundamental Research (TIFR), University of Vermont [Burlington], Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Astronomy Centre, University of Sussex, Space Telescope Science Institute (STSci), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Oxford Astrophysics, University of Oxford, Centre for Astrophysics and Supercomputing, Swinburne University of Technology [Melbourne], Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Radioastronomie (MPIFR), Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], University of Southampton, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, University of Edinburgh, Leiden Observatory [Leiden], Universiteit Leiden, Jacobs University [Bremen], Leibniz-Institut für Astrophysik Potsdam (AIP), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Thüringer Landessternwarte Tautenburg (TLS), Radboud University [Nijmegen], Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Hamburger Sternwarte/Hamburg Observatory, Universität Hamburg (UHH), Medstar Research Institute, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Center for Information Technology CIT, Université de Groningen, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), National Radio Astronomy Observatory [Charlottesville] (NRAO), National Radio Astronomy Observatory (NRAO), School of Physics and Astronomy [Southampton], SKA South Africa, Ska South Africa, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, ANR-09-JCJC-0001,OPALES(2009), Kapteyn Astronomical Institute, Astronomy, Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), University of Oxford [Oxford], Harvard University [Cambridge]-Smithsonian Institution, Universiteit Leiden [Leiden], Radboud university [Nijmegen], Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Electromagnetic field, POLARIZATION, Electromagnetic spectrum, Astrophysics::High Energy Astrophysical Phenomena, Astronomy, FOS: Physical sciences, Magnetosphere, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, EMPIRICAL-THEORY, 01 natural sciences, Binary pulsar, Pulsar, Millisecond pulsar, 0103 physical sciences, 010306 general physics, XMM-NEWTON OBSERVATIONS, 010303 astronomy & astrophysics, Astrophysics::Galaxy Astrophysics, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, DRIFTING SUBPULSES, Multidisciplinary, B0943+10, Polarization (waves), GAMMA-RAY, [SDU]Sciences of the Universe [physics], 13. Climate action, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, RADIATION, EMISSION, Astrophysics - High Energy Astrophysical Phenomena, PHOTON IMAGING CAMERA, POWERED PULSARS, Radio wave
Abstract: Pulsars emit low-frequency radio waves through to high-energy gamma-rays that are generated anywhere from the surface out to the edges of the magnetosphere. Detecting correlated mode changes in the multi-wavelength emission is therefore key to understanding the physical relationship between these emission sites. Through simultaneous observations, we have detected synchronous switching in the radio and X-ray emission properties of PSR B0943+10. When the pulsar is in a sustained radio 'bright' mode, the X-rays show only an un-pulsed, non-thermal component. Conversely, when the pulsar is in a radio 'quiet' mode, the X-ray luminosity more than doubles and a 100%-pulsed thermal component is observed along with the non-thermal component. This indicates rapid, global changes to the conditions in the magnetosphere, which challenge all proposed pulsar emission theories., Paper published in Science including supplementary material
Published: 2013
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9. Late presentation of HIV infection: a consensus definition

Author: Dorthe Raben, Margaret Johnson, Andrew N. Phillips, D Costagiola, Anders Sönnerborg, T Coenen, Jose M. Gatell, Amanda Mocroft, Andrea Antinori, N. Dedes, Ole Kirk, Jürgen K. Rockstroh, A d'Arminio Monforte, F. De Wolf, Jens D Lundgren, Caroline A. Sabin, M. Ellefson, and Enrico Girardi
Subjects: medicine.medical_specialty, business.industry, Health Policy, media_common.quotation_subject, MEDLINE, Human immunodeficiency virus (HIV), medicine.disease, medicine.disease_cause, Late presentation, Presentation, Infectious Diseases, Acquired immunodeficiency syndrome (AIDS), Family medicine, Health care, Immunology, medicine, Pharmacology (medical), Cd4 cell count, business, Health policy, media_common
Abstract: Objectives Across Europe, almost a third of individuals infected with HIV do not enter health care until late in the course of their infection. Surveillance to identify the extent to which late presentation occurs remains inadequate across Europe and is further complicated by the lack of a common clinical definition of late presentation. The objective of this article is to present a consensus definition of late presentation of HIV infection. Methods Over the past year, two initiatives have moved towards a harmonized definition. In spring 2009, they joined efforts to identify a common definition of what is meant by a ‘late-presenting’ patient. Results Two definitions were agreed upon, as follows. Late presentation: persons presenting for care with a CD4 count below 350 cells/μL or presenting with an AIDS-defining event, regardless of the CD4 cell count. Presentation with advanced HIV disease: persons presenting for care with a CD4 count below 200 cells/μL or presenting with an AIDS-defining event, regardless of the CD4 cell count. Conclusion The European Late Presenter Consensus working group believe it would be beneficial if all national health agencies, institutions, and researchers were able to implement this definition (either on its own or alongside their own preferred definition) when reporting surveillance or research data relating to late presentation of HIV infection.
Published: 2010
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10. Spatially resolved luminescence properties of non- and semi-polar InGaN quantum wells on GaN microrods

Author: K. Sebald, Marco Schowalter, C. Tessarek, K Müller-Caspari, Martin Heilmann, Jürgen Gutowski, Silke Christiansen, Andreas Rosenauer, Thorsten Mehrtens, J Dühn, T Coenen, and B. Gerken
Subjects: 010302 applied physics, Materials science, Acoustics and Ultrasonics, Spatially resolved, 02 engineering and technology, 021001 nanoscience & nanotechnology, Condensed Matter Physics, 01 natural sciences, Molecular physics, Surfaces, Coatings and Films, Electronic, Optical and Magnetic Materials, 0103 physical sciences, Polar, 0210 nano-technology, Luminescence, Quantum well
Published: 2018
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11. Overcoming obstacles to late presentation for HIV infection in Europe

Author: Anders Sönnerborg, Matthew Weait, Jeffrey V. Lazarus, Jens D Lundgren, R. Jurgens, Gatell Jm, J. Hows, AN Phillips, Dorthe Raben, and T Coenen
Subjects: European level, business.industry, Health Policy, Central asia, Human immunodeficiency virus (HIV), Public relations, medicine.disease_cause, Key issues, Late presentation, Infectious Diseases, Criminalization, Early results, Environmental protection, Medicine, Pharmacology (medical), business, Health policy
Abstract: Objective The central goal of the HIV in Europe Initiative is to promote testing and treatment throughout Europe and Central Asia in order to decrease the number of people living with HIV presenting late for care. This article summarizes the results from the HIV in Europe 2009 Conference and the early results of the projects set up by the initiative, and discusses their implications for the future. Methods In November 2009, 100 key stakeholders from 25 countries met in Stockholm at the HIV in Europe Conference. The focus was to address five key issues that contribute to the barriers to testing identified in 2007 at an innovative HIV conference. The conference discussed barriers to testing and other reasons for late presentation and outlined concrete recommendations to address the problem. Results An early result of the initiative has been stimulation of the process of reaching a consensus definition of what is meant by a ‘late presenter’, with this definition to be implemented at the European level. Steps are being taken to advocate for appropriate health policies and surveillance data related to HIV throughout Europe. Also, the initiative has set up projects related to the barriers to testing, i.e. criminalization law, stigmatization and lack of offering of testing for people presenting with certain indicator diseases. Conclusions The final results of ongoing projects will be published and widely disseminated in 2010 and beyond. The HIV in Europe Initiative will continue to reinforce collaboration, advocacy and networking activities in the field throughout Europe.
Published: 2010
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12. Monitoring Burgzand 1998 - 2016

Author: S. van den Brenk, T. Coenen, J. Opdebeeck en M.R. Manders and Periplus Archeomare
Subjects: archeologisch: geofysisch onderzoek, Scheepswrak, Archaeology, (NTL), Nieuwe Tijd Vroeg, (WRAK.SCHIP), Nieuwe Tijd Laat, (NTV), archeologie, geofysisch onderzoek IVO-O (verkennend) (AGO)
Published: 2016

13. Pulsar polarisation below 200 MHz: Average profiles and propagation effects

Author: Casey J. Law, M. Kuniyoshi, Tim D. Staley, M. Pietka, S. Cooper, Michael Kramer, Charlotte Sobey, Patrick Weltevrede, B. Scheers, S. Marko, P.G. Jonker, A. Alexov, P. Zarka, Heino Falcke, E. Rol, Aris Karastergiou, T. E. Hassall, Adam Stewart, Michael W. Wise, Rudy Wijnands, M. Pilia, James Miller-Jones, Martin Bell, Evan Keane, Jason W. T. Hessels, J. Masters, J.-M. Grießmeier, L. Bähren, Jochen Eislöffel, Antonia Rowlinson, T. Coenen, Hugh Garsden, Stefan Oslowski, J. van Leeuwen, B. W. Stappers, Rob Fender, Y. Cendes, K. Zagkouris, Anna V. Bilous, R. A. Osten, V. I. Kondratiev, John D. Swinbank, Ralph A. M. J. Wijers, Joris P. W. Verbiest, D. Carbone, S. ter Veen, A. J. van der Horst, M. Serylak, H. Spreeuw, Gijs Molenaar, Rene P. Breton, J. W. Broderick, Stephane Corbel, A. Noutsos, Kenneth C. Anderson, Netherlands Institute for Radio Astronomy (ASTRON), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], Max-Planck-Institut für Radioastronomie (MPIFR), Universität Bielefeld, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud university [Nijmegen], School of Mathematics [Cardiff], Cardiff University, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), School of Physics and Astronomy [Southampton], University of Southampton, Centre for Astrophysics and Supercomputing, Swinburne University of Technology [Melbourne], Sub-department of Astrophysics [Oxford], Department of Physics [Oxford], University of Oxford [Oxford]-University of Oxford [Oxford], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), Thüringer Landessternwarte Tautenburg (TLS), Laboratory for Atmospheric and Space Physics [Boulder] (LASP), University of Colorado [Boulder], Department of Astrophysical Sciences [Princeton], Princeton University, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), European Project: 337062,EC:FP7:ERC,ERC-2013-StG,DRAGNET(2014), Database Architectures, Radboud University [Nijmegen], Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), University of Oxford-University of Oxford, Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), High Energy Astrophys. & Astropart. Phys (API, FNWI), Jodrell Bank Centre for Astrophysics, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, and PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)
Subjects: Astronomy, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, Magnetosphere, Astrophysics, polarisation, low frequencies, Spectral line, symbols.namesake, Pulsar, Millisecond pulsar, pulsars: general, Faraday effect, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, instrumentation, polarization, Scattering, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], scattering, Astronomy and Astrophysics, LOFAR, radiation mechanisms: non-thermal, Astrophysics - Astrophysics of Galaxies, Interstellar medium, Space and Planetary Science, Astrophysics of Galaxies (astro-ph.GA), ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, symbols, pulsars, Astrophysics - High Energy Astrophysical Phenomena
Abstract: We present the highest-quality polarisation profiles to date of 16 non-recycled pulsars and four millisecond pulsars, observed below 200 MHz with the LOFAR high-band antennas. Based on the observed profiles, we perform an initial investigation of expected observational effects resulting from the propagation of polarised emission in the pulsar magnetosphere and the interstellar medium. The predictions of magnetospheric birefringence in pulsars have been tested using spectra of the pulse width and fractional polarisation from multifrequency data. The derived spectra offer only partial support for the expected effects of birefringence on the polarisation properties, with only about half of our sample being consistent with the model's predictions. It is noted that for some pulsars these measurements are contaminated by the effects of interstellar scattering. For a number of pulsars in our sample, we have observed significant variations in the amount of Faraday rotation as a function of pulse phase, which is possibly an artefact of scattering. These variations are typically two orders of magnitude smaller than that observed at 1400 MHz by Noutsos et al. (2009), for a different sample of southern pulsars. In this paper we present a possible explanation for the difference in magnitude of this effect between the two frequencies, based on scattering. Finally, we have estimated the magnetospheric emission heights of low-frequency radiation from four pulsars, based on the phase lags between the flux-density and the PA profiles, and the theoretical framework of Blaskiewicz, Cordes & Wasserman (1991). These estimates yielded heights of a few hundred km; at least for PSR B1133+16, this is consistent with emission heights derived based on radius-to-frequency mapping, but is up to a few times larger than the recent upper limit based on pulsar timing., 27 pages, 11 figures, 2 tables, A&A accepted
Published: 2015
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14. Scheepswrak Stavoren 17 ± een overnaadse koopvaarder van rond 1500 AD

Author: Opdebeeck, J., Manders, M., J. Opdebeeck, M. Manders, T. Coenen, and Rijksdienst voor het Cultureel Erfgoed
Subjects: grachten, prospectie, Archaeology, schepen, scheepsarcheologie, Middeleeuwen, Koopvaardijschepen, archeologie
Abstract: Met lit. opg.
Published: 2014

15. The LOFAR pilot surveys for pulsars and fast radio transients

Author: K. Zagkouris, Stefan Oslowski, C. Schrijvers, Michel Tagger, A. Noutsos, Jean-Mathias Grießmeier, John D. Swinbank, Simon Cooper, Dominik J. Schwarz, Rob Fender, P. Zarka, Heino Falcke, Philip Best, V. I. Kondratiev, D. McKay-Bukowski, Charlotte Sobey, Arthur Corstanje, Gerard H. Kuper, Christian Vocks, T. Coenen, M. A. Garrett, Y. Tang, M. Serylak, T. E. Hassall, Oleg Smirnov, Gottfried Mann, Olaf Wucknitz, Anna M. M. Scaife, Jason W. T. Hessels, J. Sluman, Aris Karastergiou, Gianni Bernardi, Mark J. Bentum, Michael Kramer, M. Pilia, George Heald, S. ter Veen, A. W. Gunst, H. Munk, H. J. A. Röttgering, A. S. van Amesfoort, E. de Geus, Satyendra Thoudam, Marcus Brüggen, C. Tasse, Harvey Butcher, John McKean, Emanuela Orru, Casey J. Law, M. Kuniyoshi, Chiara Ferrari, F. Breitling, Annalisa Bonafede, Joeri van Leeuwen, M. Pandey-Pommier, A. Zensus, James M. Anderson, Antonia Rowlinson, Ashish Asgekar, C. Toribio, R. Vermeulen, Joris P. W. Verbiest, Evan Keane, Matthias Hoeft, Vishal Gajjar, Jochen Eislöffel, S. Duscha, H. Paas, A. G. Polatidis, A. Alexov, Rebecca McFadden, Benedetta Ciardi, Stefan J. Wijnholds, J. W. Broderick, Richard Fallows, Wolfgang Reich, B. W. Stappers, A. Renting, F. de Gasperin, Adam T. Deller, W. Frieswijk, Martin Bell, Anna V. Bilous, R. J. van Weeren, I. M. Avruch, E. Juette, Patrick Weltevrede, J. P. Hamaker, A. J. van der Horst, Rene P. Breton, Kapteyn Astronomical Institute, Astronomy, Netherlands Institute for Radio Astronomy (ASTRON), University of Amsterdam [Amsterdam] (UvA), Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], University of Southampton, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud University [Nijmegen], Max-Planck-Institut für Radioastronomie (MPIFR), Unité Scientifique de la Station de Nançay (USN), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), University of Oxford, Universität Bielefeld, Leibniz-Institut für Astrophysik Potsdam (AIP), SRON Netherlands Institute for Space Research (SRON), Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University-Smithsonian Institution, University of Edinburgh, Jacobs University [Bremen], Universität Hamburg (UHH), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Thüringer Landessternwarte Tautenburg (TLS), Joseph Louis LAGRANGE (LAGRANGE), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory [Leiden], Universiteit Leiden, Ruhr-Universität Bochum [Bochum], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Oulu, Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), School of Physics and Astronomy [Southampton], Rhodes University, Grahamstown, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), ANR-09-JCJC-0001,OPALES(2009), European Project: 224838,EC:FP7:PEOPLE,FP7-PEOPLE-2007-4-3-IRG,PULSARS WITH LOFAR(2008), High Energy Astrophys. & Astropart. Phys (API, FNWI), Radboud university [Nijmegen], Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), University of Oxford [Oxford], Harvard University [Cambridge]-Smithsonian Institution, Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden [Leiden], École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Jodrell Bank Centre for Astrophysics, Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Centre National d’Études Spatiales [Paris] (CNES), Smithsonian Institution-Harvard University [Cambridge], Université Nice Sophia Antipolis (... - 2019) (UNS), Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA (UMR_8109)), PSL Research University (PSL)-PSL Research University (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Sorbonne Université (SU)-Centre National de la Recherche Scientifique (CNRS), ANR-09-JCJC-0001,OPALES,nOn-thermal Processes in gALaxy cluStErs(2009), Coenen, Thij, Van Leeuwen, Joeri, Hessels, Jason W. T., Stappers, Ben W., Kondratiev, Vladislav I., Alexov, A., Breton, R.P., Bilous, A., Cooper, S., Falcke, H., Fallows, R.A., Gajjar, V., Grießmeier, J.-M., Hassall, T.E., Karastergiou, A., Keane, E.F., Kramer, M., Kuniyoshi, M., Noutsos, A., Osłowski, S., Pilia, M., Serylak, M., Schrijvers, C., Sobey, C., Ter Veen, S., Verbiest, J., Weltevrede, P., Wijnholds, S., Zagkouris, K., Van Amesfoort, A.S., Anderson, J., Asgekar, A., Avruch, I.M., Bell, M.E., Bentum, M.J., Bernardi, G., Best, P., Bonafede, A., Breitling, F., Broderick, J., Brüggen, M., Butcher, H.R., Ciardi, B., Corstanje, A., Deller, A., Duscha, S., Eislöffel, J., Fender, R., Ferrari, C., Frieswijk, W., Garrett, M.A., De Gasperin, F., De Geus, E., Gunst, A.W., Hamaker, J.P., Heald, G., Hoeft, M., Van Der Horst, A., Juette, E., Kuper, G., Law, C., Mann, G., McFadden, R., McKay-Bukowski, D., McKean, J.P., Munk, H., Orru, E., Paas, H., Pandey-Pommier, M., Polatidis, A.G., Reich, W., Renting, A., Röttgering, H., Rowlinson, A., Scaife, A.M.M., Schwarz, D., Sluman, J., Smirnov, O., Swinbank, J., Tagger, M., Tang, Y., Tasse, C., Thoudam, S., Toribio, C., Vermeulen, R., Vocks, C., Van Weeren, R.J., Wucknitz, O., Zarka, P., and Zensus, A.
Subjects: EWI-25426, Aperture array, media_common.quotation_subject, Astronomy, Pilot survey, SPECTRAL INDEX, FOS: Physical sciences, Astrophysics, general [pulsars], METIS-309729, MHZ, Pulsar, surveys, pulsars: general, BURSTS, Survey, Telescope, POPULATION, Solar and Stellar Astrophysics (astro-ph.SR), media_common, Physics, High Energy Astrophysical Phenomena (astro-ph.HE), [PHYS]Physics [physics], ORIGIN, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, telescopes, BINARY, LOFAR, Astronomy and Astrophysic, IR-93231, Astrophysics - Solar and Stellar Astrophysics, Sky, Space and Planetary Science, DISCOVERY, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, STATE CHANGE, Antenna (radio), ALLEN TELESCOPE ARRAY, EMISSION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], Astrophysics - High Energy Astrophysical Phenomena
Abstract: We have conducted two pilot surveys for radio pulsars and fast transients with the Low-Frequency Array (LOFAR) around 140 MHz and here report on the first low-frequency fast-radio burst limit and the discovery of two new pulsars. The first survey, the LOFAR Pilot Pulsar Survey (LPPS), observed a large fraction of the northern sky, ~1.4 x 10^4 sq. deg, with 1-hr dwell times. Each observation covered ~75 sq. deg using 7 independent fields formed by incoherently summing the high-band antenna fields. The second pilot survey, the LOFAR Tied-Array Survey (LOTAS), spanned ~600 sq. deg, with roughly a 5-fold increase in sensitivity compared with LPPS. Using a coherent sum of the 6 LOFAR "Superterp" stations, we formed 19 tied-array beams, together covering 4 sq. deg per pointing. From LPPS we derive a limit on the occurrence, at 142 MHz, of dispersed radio bursts of < 150 /day/sky, for bursts brighter than S > 107 Jy for the narrowest searched burst duration of 0.66 ms. In LPPS, we re-detected 65 previously known pulsars. LOTAS discovered two pulsars, the first with LOFAR or any digital aperture array. LOTAS also re-detected 27 previously known pulsars. These pilot studies show that LOFAR can efficiently carry out all-sky surveys for pulsars and fast transients, and they set the stage for further surveying efforts using LOFAR and the planned low-frequency component of the Square Kilometer Array., 18 pages, 10 figures, accepted for A&A
Published: 2014
Full Text: View/download PDF

16. Conclusions from the HIV in Europe Copenhagen 2012 Conference and ways forward: working together for optimal HIV testing and earlier care

Author: D, Raben, V, Delpech, J, de Wit, A, Sullivan, J V, Lazarus, N, Dedes, T, Coenen, and J, Lundgren
Subjects: Europe, Delayed Diagnosis, Denmark, HIV Seropositivity, HIV, Humans, Mass Screening, Congresses as Topic, Hepatitis
Abstract: The objective of this article is to set the scene for this supplement by presenting and discussing the overall outcomes of the HIV in Europe Copenhagen 2012 Conference and how the HIV in Europe initiative intends to further address challenges and themes raised during the conference.
Published: 2013

17. The role of nitric oxide in genetic model of absence epilepsy in rats

Author: W. Lason, G. van Luijtelaar, B. Przewlocka, T. Coenen, and R. Przewlocki
Subjects: Epilepsy, chemistry.chemical_compound, chemistry, business.industry, General Neuroscience, Anesthesia, Genetic model, Medicine, business, medicine.disease, Bioinformatics, Nitric oxide
Abstract: Item does not contain fulltext
Published: 1996

18. The case for indicator condition-guided HIV screening

Author: J V, Lazarus, M, Hoekstra, D, Raben, V, Delpech, T, Coenen, and J D, Lundgren
Subjects: Europe, Male, Early Diagnosis, Prenatal Diagnosis, Prevalence, HIV, Health Status Indicators, Humans, HIV Infections, Homosexuality, Male, Patient Acceptance of Health Care, World Health Organization
Abstract: One-half of the estimated 2.5 million people who now live with HIV in the World Health Organization (WHO) European Region are still diagnosed late. A central question is which clinical scenarios should trigger an HIV test recommendation in order to avoid late presentation. Drawing on the work of the HIV Indicator Diseases across Europe Study (HIDES), new guidance brings together in one place a list of the conditions that should result in an HIV screening recommendation.
Published: 2013

19. Resonant Mie modes of single silicon nanocavities excited by electron irradiation

Author: T. Coenen, J. van de Groep, and A. Polman
Published: 2013

20. LOFAR: The LOw-Frequency ARray

Author: M. P. van Haarlem, M. W. Wise, A. W. Gunst, G. Heald, J. P. McKean, J. W. T. Hessels, A. G. de Bruyn, R. Nijboer, J. Swinbank, R. Fallows, M. Brentjens, A. Nelles, R. Beck, H. Falcke, R. Fender, J. Hörandel, L. V. E. Koopmans, G. Mann, G. Miley, H. Röttgering, B. W. Stappers, R. A. M. J. Wijers, S. Zaroubi, M. van den Akker, A. Alexov, J. Anderson, K. Anderson, A. van Ardenne, M. Arts, A. Asgekar, I. M. Avruch, F. Batejat, L. Bähren, M. E. Bell, M. R. Bell, I. van Bemmel, P. Bennema, M. J. Bentum, G. Bernardi, P. Best, L. Bîrzan, A. Bonafede, A.-J. Boonstra, R. Braun, J. Bregman, F. Breitling, R. H. van de Brink, J. Broderick, P. C. Broekema, W. N. Brouw, M. Brüggen, H. R. Butcher, W. van Cappellen, B. Ciardi, T. Coenen, J. Conway, A. Coolen, A. Corstanje, S. Damstra, O. Davies, A. T. Deller, R.-J. Dettmar, G. van Diepen, K. Dijkstra, P. Donker, A. Doorduin, J. Dromer, M. Drost, A. van Duin, J. Eislöffel, J. van Enst, C. Ferrari, W. Frieswijk, H. Gankema, M. A. Garrett, F. de Gasperin, M. Gerbers, E. de Geus, J.-M. Grießmeier, T. Grit, P. Gruppen, J. P. Hamaker, T. Hassall, M. Hoeft, H. A. Holties, A. Horneffer, A. van der Horst, A. van Houwelingen, A. Huijgen, M. Iacobelli, H. Intema, N. Jackson, V. Jelic, A. de Jong, E. Juette, D. Kant, A. Karastergiou, A. Koers, H. Kollen, V. I. Kondratiev, E. Kooistra, Y. Koopman, A. Koster, M. Kuniyoshi, M. Kramer, G. Kuper, P. Lambropoulos, C. Law, J. van Leeuwen, J. Lemaitre, M. Loose, P. Maat, G. Macario, S. Markoff, J. Masters, R. A. McFadden, D. McKay-Bukowski, H. Meijering, H. Meulman, M. Mevius, E. Middelberg, R. Millenaar, J. C. A. Miller-Jones, R. N. Mohan, J. D. Mol, J. Morawietz, R. Morganti, D. D. Mulcahy, E. Mulder, H. Munk, L. Nieuwenhuis, R. van Nieuwpoort, J. E. Noordam, M. Norden, A. Noutsos, A. R. Offringa, H. Olofsson, A. Omar, E. Orrú, R. Overeem, H. Paas, M. Pandey-Pommier, V. N. Pandey, R. Pizzo, A. Polatidis, D. Rafferty, S. Rawlings, W. Reich, J.-P. de Reijer, J. Reitsma, G. A. Renting, P. Riemers, E. Rol, J. W. Romein, J. Roosjen, M. Ruiter, A. Scaife, K. van der Schaaf, B. Scheers, P. Schellart, A. Schoenmakers, G. Schoonderbeek, M. Serylak, A. Shulevski, J. Sluman, O. Smirnov, C. Sobey, H. Spreeuw, M. Steinmetz, C. G. M. Sterks, H.-J. Stiepel, K. Stuurwold, M. Tagger, Y. Tang, C. Tasse, I. Thomas, S. Thoudam, M. C. Toribio, B. van der Tol, O. Usov, M. van Veelen, A.-J. van der Veen, S. ter Veen, J. P. W. Verbiest, R. Vermeulen, N. Vermaas, C. Vocks, C. Vogt, M. de Vos, E. van der Wal, R. van Weeren, H. Weggemans, P. Weltevrede, S. White, S. J. Wijnholds, T. Wilhelmsson, O. Wucknitz, S. Yatawatta, P. Zarka, A. Zensus, J. van Zwieten, Netherlands Institute for Radio Astronomy (ASTRON), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Institute of Mathematical and Physical Sciences, Radboud university [Nijmegen], Laboratoire de Chimie Physique Moléculaire (LCPM), Ecole Polytechnique Fédérale de Lausanne (EPFL), Max-Planck-Institut für Radioastronomie (MPIFR), University of Southampton, Leibniz-Institut für Astrophysik Potsdam (AIP), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Medical Center Haaglanden, SRON Netherlands Institute for Space Research (SRON), University of Edinburgh, Jacobs University [Bremen], Technische Universität Dresden = Dresden University of Technology (TU Dresden), Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Department of Reproduction and Development, Erasmus University Rotterdam, London Institute for Mathematical Sciences, Netherlands Centre for Biodiversity, Leiden, The Netherlands, Thüringer Landessternwarte Tautenburg (TLS), Laboratoire Réactions et Génie des Procédés (LRGP), Université de Lorraine (UL)-Centre National de la Recherche Scientifique (CNRS), Medstar Research Institute, Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Plant Research International, Business Unit Bioscience, Wageningen University and Research [Wageningen] (WUR), Dipartimento di Matematica 'Guido Castelnuovo' [Roma I] (Sapienza University of Rome), Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome], Centre de Mathématiques Laurent Schwartz (CMLS), Centre National de la Recherche Scientifique (CNRS)-École polytechnique (X), Peuplements végétaux et bioagresseurs en milieu tropical (UMR PVBMT), Centre de Coopération Internationale en Recherche Agronomique pour le Développement (Cirad)-Institut de Recherche pour le Développement (IRD)-Institut National de la Recherche Agronomique (INRA)-Université de La Réunion (UR), Ruhr-Universität Bochum [Bochum], Oxford Astrophysics, University of Oxford [Oxford], Amsterdam Center for Multiscale Modeling, Vrije Universiteit Amsterdam [Amsterdam] (VU), Vrije Universiteit Medical Centre (VUMC), Queen's Medical Centre, National Radio Astronomy Observatory (NRAO), University of Oulu, Department of Economics, Bryant University, Center for Agricultural Research in Suriname CELOS and Department of Biology, Anton de Kom Universiteit van Suriname - Anton de Kom University of Suriname [Paramaribo] (UVS), DLR Institute of Aerospace Medicine, Deutsches Zentrum für Luft- und Raumfahrt [Köln] (DLR), Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], Geophysical Institute [Bergen] (GFI / BiU), University of Bergen (UiB), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Department of Astronomy and Astrophysics [PennState], Pennsylvania State University (Penn State), Penn State System-Penn State System, Academic Medical Center - Academisch Medisch Centrum [Amsterdam] (AMC), School of Physics and Astronomy [Southampton], Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Rhodes University, Grahamstown, Center for Information Technology CIT, Université de Groningen, Processus d'Activation Sélective par Transfert d'Energie Uni-électronique ou Radiatif (UMR 8640) (PASTEUR), Université Pierre et Marie Curie - Paris 6 (UPMC)-Département de Chimie - ENS Paris, École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS Paris), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut de Chimie du CNRS (INC)-Centre National de la Recherche Scientifique (CNRS), Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Center for Operations and Econometrics, Center of Operation Research and Econometrics [Louvain] (CORE), Université Catholique de Louvain = Catholic University of Louvain (UCL)-Université Catholique de Louvain = Catholic University of Louvain (UCL), Finca El Encin, Instituto Madrileño de Investigación y Desarrollo Rural, Agrario y Alimentario (IMIDRA), Department of Surgery (EINDHOVEN - Surgery), Catharina Hospital, Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Harvard-Smithsonian Center for Astrophysics (CfA), Smithsonian Institution-Harvard University [Cambridge], Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, ANR-09-JCJC-0001,OPALES(2009), Astronomy, KVI - Center for Advanced Radiation Technology, Radboud University [Nijmegen], Universiteit Leiden, Università degli Studi di Roma 'La Sapienza' = Sapienza University [Rome] (UNIROMA), École polytechnique (X)-Centre National de la Recherche Scientifique (CNRS), University of Oxford, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), École normale supérieure - Paris (ENS-PSL), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-École normale supérieure - Paris (ENS-PSL), Harvard University-Smithsonian Institution, UMR Peuplement Végétaux et Bioagresseurs en Milieu Tropical (UMR PVBMT - INRA), Institut National de la Recherche Agronomique (INRA), Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Technische Universität Dresden (TUD), university Rotterdam, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Wageningen University and Research Centre [Wageningen] (WUR), Università degli Studi di Roma 'La Sapienza' [Rome], Department of Physics, University of Crete [Heraklion] (UOC), Institute of Electronic Structure and Laser, Foundation for Research and Technology - Hellas (FORTH), Anton de Kom University of Suriname, Geophysical Institute [Bergen], University of Bergen (UIB), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), Rhodes University, École normale supérieure - Paris (ENS Paris)-École normale supérieure - Paris (ENS Paris)-Centre National de la Recherche Scientifique (CNRS), SKA South Africa, Ska South Africa, Center for Operations and Econometrics, Universit´e catholique de Louvain and Fonds National de la Recherche Scientifique, Harvard University [Cambridge]-Smithsonian Institution, Observatoire de Paris - Site de Paris (OP), PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS), ANR-09-JCJC-0001,OPALES,nOn-thermal Processes in gALaxy cluStErs(2009), High Energy Astrophys. & Astropart. Phys (API, FNWI), 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., Van Den Akker, M., 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.A., 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., McFadden, R.A., 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, G.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: instrumentation: interferometers -radio continuum: general -radio lines: general -dark ages, Computer science, Astronomy, INTERPLANETARY SCINTILLATION, radio continuum: general, 7. Clean energy, 01 natural sciences, Precision Array for Probing the Epoch of Reionization, law.invention, Observatory, law, first stars - telescopes, dark ages, instrumentation: interferometers, 010303 astronomy & astrophysics, Telescope, UNDERSTANDING RADIO POLARIMETRY, Instrumentation: Interferometer, SELF-CALIBRATION, Interferometry, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, reionization, Astrophysics - Instrumentation and Methods for Astrophysics, radio lines: general, first stars, Z-GREATER-THAN-5.7 QUASARS, FOS: Physical sciences, Murchison Widefield Array, 0103 physical sciences, RAY AIR-SHOWERS, Angular resolution, dark ages, reionization, first stars, Instrumentation and Methods for Astrophysics (astro-ph.IM), Remote sensing, 010308 nuclear & particles physics, telescopes, Astronomy and Astrophysics, LOFAR, Astronomy and Astrophysic, Sextant (astronomical), Dark ages, reionization, first star, Space and Planetary Science, [SDU]Sciences of the Universe [physics], PROBE WMAP OBSERVATIONS, DIGITAL SKY SURVEY, HIGH-REDSHIFT, MONTE-CARLO SIMULATIONS, INTERGALACTIC MEDIUM
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
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21. Wide-band simultaneous observations of pulsars: disentangling dispersion measure and profile variations

Author: P. Maat, Benjamin Stappers, Heino Falcke, Charlotte Sobey, Emanuela Orrú, Jason W. T. Hessels, E. Rol, L. Bähren, H. Meulman, Joris P. W. Verbiest, C. Tasse, A. Alexov, Matthias Hoeft, M. A. Garrett, Sarod Yatawatta, James Miller-Jones, Evan Keane, Michael Kramer, S. ter Veen, J. Masters, A. W. Gunst, Casey J. Law, Jochen Eislöffel, B. Scheers, Maaijke Mevius, T. E. Hassall, J. W. Broderick, R. C. Vermeulen, B. Ciardi, Martin Bell, John McKean, Luitje Koopmans, J. E. Noordam, Gerard H. Kuper, Annalisa Bonafede, Harvey Butcher, Sera Markoff, M. P. van Haarlem, E. J. Daw, Rudy Wijnands, M. Kuniyoshi, V. I. Kondratiev, M. Pandey-Pommier, A. Noutsos, K. Zagkouris, Michael R. Bell, H. Paas, J. Sluman, Michiel A. Brentjens, Ashish Asgekar, Roberto Pizzo, Marcus Brüggen, C. G. M. Sterks, W. Reich, R. A. Osten, Albert-Jan Boonstra, Michel Tagger, Stephane Corbel, A. G. Polatidis, P.G. Jonker, M. Gerbers, Stefan J. Wijnholds, J. van Leeuwen, H. Spreeuw, A. de Jong, Matthias Steinmetz, R. J. van Weeren, P. Zarka, K. Lazaridis, George Heald, Mark J. Bentum, G. M. Loose, W. N. Brouw, Patrick Weltevrede, V. S. Dhillon, Aris Karastergiou, Michael W. Wise, Gianni Bernardi, M. Serylak, Rob Fender, Ralph A. M. J. Wijers, H. J. A. Röttgering, H. A. Holties, Y. Tang, Anna M. M. Scaife, Olaf Wucknitz, H. Munk, John D. Swinbank, Jean-Mathias Griessmeier, Vishambhar Pandey, Philip Best, Pim Schellart, T. Coenen, Kenneth C. Anderson, Kapteyn Astronomical Institute, Astronomy, Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Radioastronomie (MPIFR), Oxford Astrophysics, University of Oxford [Oxford], Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), University of Southampton, Astronomical Institute Anton Pannekoek (AI PANNEKOEK), University of Amsterdam [Amsterdam] (UvA), Astrophysique Interprétation Modélisation (AIM (UMR_7158 / UMR_E_9005 / UM_112)), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Université Paris Diderot - Paris 7 (UPD7), University of Sheffield [Sheffield], Thüringer Landessternwarte Tautenburg (TLS), Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud university [Nijmegen], Space Telescope Science Institute (STSci), School of Physics and Astronomy [Southampton], Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Harvard-Smithsonian Center for Astrophysics (CfA), Harvard University [Cambridge]-Smithsonian Institution, University of Edinburgh, Jacobs University [Bremen], Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Leiden Observatory [Leiden], Universiteit Leiden [Leiden], National Radio Astronomy Observatory (NRAO), Applied Stochastics (IMAPP), Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Leibniz-Institut DSMZ-Deutsche Sammlung von Mikroorganismen und Zellkulturen GmbH / Leibniz Institute DSMZ-German Collection of Microorganisms and Cell Cultures (DSMZ), Center for Information Technology CIT, Université de Groningen, Netherlands Foundation for Scientific Research. Joeri van Leeuwen and ThijsCoenen are supported by the Netherlands Research School for Astronomy (GrantNOVA3-NW3-2.3.1), European Project: 224838,EC:FP7:PEOPLE,FP7-PEOPLE-2007-4-3-IRG,PULSARS WITH LOFAR(2008), European Project: 236394,EC:FP7:PEOPLE,FP7-PEOPLE-IEF-2008,PULSAR SURVEY(2010), Hassall, T.E., Stappers, B.W., Hessels, J.W.T., Kramer, M., Alexov, A., Anderson, K., Coenen, T., Karastergiou, A., Keane, E.F., Kondratiev, V.I., Lazaridis, K., Van Leeuwen, J., Noutsos, A., Serylak, M., Sobey, C., Verbiest, J.P.W., Weltevrede, P., Zagkouris, K., Fender, R., Wijers, R.A.M.J., Bähren, L., Bell, M.E., Broderick, J.W., Corbel, S., Daw, E.J., Dhillon, V.S., Eislöffel, J., Falcke, H., Grießmeier, J.-M., Jonker, P., Law, C., Markoff, S., Miller-Jones, J.C.A., Osten, R., Rol, E., Scaife, A.M.M., Scheers, B., Schellart, P., Spreeuw, H., Swinbank, J., Ter Veen, S., Wise, M.W., Wijnands, R., Wucknitz, O., Zarka, P., Asgekar, A., Bell, M.R., Bentum, M.J., Bernardi, G., Best, P., Bonafede, A., Boonstra, A.J., Brentjens, M., Brouw, W.N., Brüggen, M., Butcher, H.R., Ciardi, B., Garrett, M.A., Gerbers, M., Gunst, A.W., Van Haarlem, M.P., Heald, G., Hoeft, M., Holties, H., De Jong, A., Koopmans, L.V.E., Kuniyoshi, M., Kuper, G., Loose, G.M., Maat, P., Masters, J., McKean, J.P., Meulman, H., Mevius, M., Munk, H., Noordam, J.E., Orrú, E., Paas, H., Pandey-Pommier, M., Pandey, V.N., Pizzo, R., Polatidis, A., Reich, W., Röttgering, H., Sluman, J., Steinmetz, M., Sterks, C.G.M., Tagger, M., Tang, Y., Tasse, C., Vermeulen, R., Van Weeren, R.J., Wijnholds, S.J., Yatawatta, S., University of Oxford, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Astrophysique Interprétation Modélisation (AIM (UMR7158 / UMR_E_9005 / UM_112)), Commissariat à l'énergie atomique et aux énergies alternatives (CEA)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Radboud University [Nijmegen], Harvard University-Smithsonian Institution, Universiteit Leiden, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), High Energy Astrophys. & Astropart. Phys (API, FNWI), Université d'Orléans (UO)-Observatoire des Sciences de l'Univers en région Centre (OSUC), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, PSL Research University (PSL)-Centre National de la Recherche Scientifique (CNRS), PSL Research University (PSL)-PSL Research University (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Observatoire de Paris, PSL Research University (PSL)-PSL Research University (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC), Rhodes University, SKA South Africa, and Ska South Africa
Subjects: 010504 meteorology & atmospheric sciences, Astronomy, Magnetosphere, Astrophysics, magnetic fields, 01 natural sciences, law.invention, law, Dispersion (optics), 010303 astronomy & astrophysics, Telescope, High Energy Astrophysical Phenomena (astro-ph.HE), Physics, [PHYS]Physics [physics], Astrophysics::Instrumentation and Methods for Astrophysics, SPECTRAL BEHAVIOR, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, Astrophysics - High Energy Astrophysical Phenomena, ARRIVAL-TIME DELAY, Astrophysics::High Energy Astrophysical Phenomena, FOS: Physical sciences, SUPERDISPERSION DELAY, EMPIRICAL-THEORY, Pulsar, pulsars: general, 0103 physical sciences, Astrophysics::Galaxy Astrophysics, 0105 earth and related environmental sciences, ISM: general, METIS-287956, Gravitational wave, Astronomy and Astrophysics, telescopes, LOFAR, Astronomy and Astrophysic, EWI-22107, Pulse (physics), PULSES, Interstellar medium, PSR 0809&74, FREQUENCY-DEPENDENCE, Magnetic field, Space and Planetary Science, [SDU]Sciences of the Universe [physics], RADIO-EMISSION, IR-80985, REFRACTION, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph], INTERSTELLAR SCATTERING
Abstract: Dispersion in the interstellar medium is a well known phenomenon that follows a simple relationship, which has been used to predict the time delay of dispersed radio pulses since the late 1960s. We performed wide-band simultaneous observations of four pulsars with LOFAR (at 40-190 MHz), the 76-m Lovell Telescope (at 1400 MHz) and the Effelsberg 100-m Telescope (at 8000 MHz) to test the accuracy of the dispersion law over a broad frequency range. In this paper we present the results of these observations which show that the dispersion law is accurate to better than 1 part in 100000 across our observing band. We use this fact to constrain some of the properties of the ISM along the line-of-sight and use the lack of any aberration or retardation effects to determine upper limits on emission heights in the pulsar magnetosphere. We also discuss the effect of pulse profile evolution on our observations, and the implications that it could have for precision pulsar timing projects such as the detection of gravitational waves with pulsar timing arrays., 20 Pages, 14 Figures, Accepted for publication in Astronomy & Astrophysics
Published: 2012
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22. An Essay on Originalism and the 'Individual Mandate': Rounding Out the Government’s Case for Constitutionality

Author: Dan T. Coenen
Subjects: Government, Originalism, Commerce Clause, Necessary and Proper Clause, Constitutionality, Political science, Law, Patient Protection and Affordable Care Act, Constitutional law, Supreme court
Abstract: The Supreme Court now has under advisement the landmark federal health care law case. Much attention has focused on the law’s minimum coverage provision—or so-called “individual mandate” — and, in particular, its constitutionality under the Commerce Clause and the Necessary and Proper Clause. In a separate and much lengthier article, I offer two main observations about the arguments made to the Court on that issue. First, I show that the challengers of the minimum coverage provision emphasized originalist reasoning in their briefs and oral arguments, while the federal government did not. Second, I explain why — contrary to the impression created by the contrasting submissions of the parties — there are in fact powerful, originalism-based reasons for concluding that the minimum coverage provision is constitutional. In this Essay, I offer a streamlined version of my earlier analysis, while also developing additional points along the way. Different observers who take different views of constitutional analysis will inevitably reach different conclusions about the constitutionality of the minimum coverage provision. All serious analysts, however, should take account of a critical, but previously undeveloped point: Originalism-based arguments that were not fully aired before the Court offer strong support for the provision’s constitutionality.
Published: 2012
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23. Observing pulsars and fast transients with LOFAR

Author: S. ter Veen, A. W. Gunst, John D. Swinbank, T. Grit, R.-J. Dettmar, Sera Markoff, Patrick Weltevrede, M. A. Garrett, J. Sluman, Léon V. E. Koopmans, P. Maat, George Heald, John McKean, J. P. Hamaker, M. J. Norden, H. J. A. Röttgering, Sarod Yatawatta, V. S. Dhillon, Aris Karastergiou, J. D. Mol, A. Noutsos, M. P. van Haarlem, C. G. M. Sterks, Y. Tang, Casey J. Law, Stefan J. Wijnholds, Ashish Asgekar, Jason W. T. Hessels, Jochen Eislöffel, W. N. Brouw, A. van Duin, P. Bennema, M. Gerbers, J. W. Broderick, V. I. Kondratiev, P. C. Broekema, Michael W. Wise, Harvey Butcher, A. Alexov, James Miller-Jones, Oleg Smirnov, H. Spreeuw, L. Bähren, M. Loose, Joel N. Bregman, J. Noordam, A. G. de Bruyn, Philippe Zarka, R. Vermeulen, A. G. Polatidis, Marcus Brüggen, Heino Falcke, Kenneth C. Anderson, Matthias Hoeft, Matthias Steinmetz, A. Zensus, H. A. Holties, M. Pandey-Pommier, A. Schoenmakers, Olaf Wucknitz, Gerard H. Kuper, C. Vogt, Michael Kramer, Hans Olofsson, Bart Scheers, J. M. Anderson, N. J. Vermaas, Philip Best, T. E. Hassall, B. W. Stappers, D. McKay-Bukowski, R. Nijboer, Rob Fender, Ralph A. M. J. Wijers, T. Coenen, M. de Vos, George K. Miley, Mark J. Bentum, Rainer Beck, R. H. van de Brink, John Conway, Wolfgang Reich, Michel Tagger, E. J. Daw, Martin Bell, I. M. Avruch, B. Ciardi, A. Horneffer, John W. Romein, J. van Enst, Michiel A. Brentjens, J. van Leeuwen, J. M. Griessmeier, Raffaella Morganti, Kapteyn Astronomical Institute, Astronomy, Jodrell Bank Centre for Astrophysics (JBCA), University of Manchester [Manchester], University of Amsterdam [Amsterdam] (UvA), Astronomical Institute Anton Pannekoek (AI PANNEKOEK), Oxford Astrophysics, University of Oxford [Oxford], Netherlands Institute for Radio Astronomy (ASTRON), Max-Planck-Institut für Radioastronomie (MPIFR), University of Southampton, University of Sheffield [Sheffield], Thüringer Landessternwarte Tautenburg (TLS), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Institute for Mathematics, Astrophysics and Particle Physics (IMAPP), Radboud university [Nijmegen], Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Observatoire de Paris - Site de Paris (OP), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Centre National de la Recherche Scientifique (CNRS), SRON Netherlands Institute for Space Research (SRON), Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Jacobs University [Bremen], Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Astronomisches Institut der Ruhr-Universität Bochum, Ruhr-Universität Bochum [Bochum], Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), Netherlands Research School for Astronomy (Grant NOVA3-NW3-2.3.1), European Project: 224838,EC:FP7:PEOPLE,FP7-PEOPLE-2007-4-3-IRG,PULSARS WITH LOFAR(2008), University of Oxford, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Radboud University [Nijmegen], Universiteit Leiden, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: DECAMETER WAVELENGTHS, Computer science, Astronomy, EWI-20531, INTENSITY VARIATIONS, 01 natural sciences, law.invention, FLUX DENSITIES, law, METIS-279184, instrumentation: interferometers, 010303 astronomy & astrophysics, GeneralLiterature_REFERENCE(e.g.,dictionaries,encyclopedias,glossaries), Astrophysics::Instrumentation and Methods for Astrophysics, INTERSTELLAR PLASMA, Astrophysics - Solar and Stellar Astrophysics, LOW-FREQUENCY, Radio frequency, Ionosphere, methods: observational, Astrophysics - Instrumentation and Methods for Astrophysics, Radio astronomy, Radio wave, BINARY MILLISECOND PULSAR, GAMMA-RAY PULSARS, NEUTRON-STARS, Astrophysics::High Energy Astrophysical Phenomena, IR-78088, FOS: Physical sciences, Astrophysics::Cosmology and Extragalactic Astrophysics, Low frequency, RADIO-CONTINUUM EMISSION, Radio telescope, Telescope, stars: neutron, Pulsar, pulsars: general, 0103 physical sciences, Instrumentation and Methods for Astrophysics (astro-ph.IM), Solar and Stellar Astrophysics (astro-ph.SR), ISM: general, 010308 nuclear & particles physics, Radio window, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, telescopes, LOFAR, [SDU.ASTR.IM]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Instrumentation and Methods for Astrophysic [astro-ph.IM], Space and Planetary Science, DENSITY POWER SPECTRUM
Abstract: Low frequency radio waves, while challenging to observe, are a rich source of information about pulsars. The LOw Frequency ARray (LOFAR) is a new radio interferometer operating in the lowest 4 octaves of the ionospheric "radio window": 10-240MHz, that will greatly facilitate observing pulsars at low radio frequencies. Through the huge collecting area, long baselines, and flexible digital hardware, it is expected that LOFAR will revolutionize radio astronomy at the lowest frequencies visible from Earth. LOFAR is a next-generation radio telescope and a pathfinder to the Square Kilometre Array (SKA), in that it incorporates advanced multi-beaming techniques between thousands of individual elements. We discuss the motivation for low-frequency pulsar observations in general and the potential of LOFAR in addressing these science goals. We present LOFAR as it is designed to perform high-time-resolution observations of pulsars and other fast transients, and outline the various relevant observing modes and data reduction pipelines that are already or will soon be implemented to facilitate these observations. A number of results obtained from commissioning observations are presented to demonstrate the exciting potential of the telescope. This paper outlines the case for low frequency pulsar observations and is also intended to serve as a reference for upcoming pulsar/fast transient science papers with LOFAR., Comment: 35 pages, 19 figures, accepted for publication by A&A
Published: 2011
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24. Overcoming obstacles to late presentation for HIV infection in Europe

Author: J V, Lazarus, R, Jürgens, M, Weait, A, Phillips, J, Hows, J, Gatell, T, Coenen, A, Sönnerborg, D, Raben, and J D, Lundgren
Subjects: Europe, Male, Health Policy, HIV-1, AIDS Serodiagnosis, Humans, Female, HIV Infections
Abstract: The central goal of the HIV in Europe Initiative is to promote testing and treatment throughout Europe and Central Asia in order to decrease the number of people living with HIV presenting late for care. This article summarizes the results from the HIV in Europe 2009 Conference and the early results of the projects set up by the initiative, and discusses their implications for the future.In November 2009, 100 key stakeholders from 25 countries met in Stockholm at the HIV in Europe Conference. The focus was to address five key issues that contribute to the barriers to testing identified in 2007 at an innovative HIV conference. The conference discussed barriers to testing and other reasons for late presentation and outlined concrete recommendations to address the problem.An early result of the initiative has been stimulation of the process of reaching a consensus definition of what is meant by a 'late presenter', with this definition to be implemented at the European level. Steps are being taken to advocate for appropriate health policies and surveillance data related to HIV throughout Europe. Also, the initiative has set up projects related to the barriers to testing, i.e. criminalization law, stigmatization and lack of offering of testing for people presenting with certain indicator diseases.The final results of ongoing projects will be published and widely disseminated in 2010 and beyond. The HIV in Europe Initiative will continue to reinforce collaboration, advocacy and networking activities in the field throughout Europe.
Published: 2010

25. Late presentation of HIV infection: a consensus definition

Author: A, Antinori, T, Coenen, D, Costagiola, N, Dedes, M, Ellefson, J, Gatell, E, Girardi, M, Johnson, O, Kirk, J, Lundgren, A, Mocroft, A, D'Arminio Monforte, A, Phillips, D, Raben, J K, Rockstroh, C, Sabin, A, Sönnerborg, and F, De Wolf
Subjects: Europe, Consensus, Delayed Diagnosis, Time Factors, Health Policy, Humans, HIV Infections, Patient Acceptance of Health Care, CD4 Lymphocyte Count
Abstract: Across Europe, almost a third of individuals infected with HIV do not enter health care until late in the course of their infection. Surveillance to identify the extent to which late presentation occurs remains inadequate across Europe and is further complicated by the lack of a common clinical definition of late presentation. The objective of this article is to present a consensus definition of late presentation of HIV infection.Over the past year, two initiatives have moved towards a harmonized definition. In spring 2009, they joined efforts to identify a common definition of what is meant by a 'late-presenting' patient.Two definitions were agreed upon, as follows. Late presentation: persons presenting for care with a CD4 count below 350 cells/μL or presenting with an AIDS-defining event, regardless of the CD4 cell count. Presentation with advanced HIV disease: persons presenting for care with a CD4 count below 200 cells/μL or presenting with an AIDS-defining event, regardless of the CD4 cell count.The European Late Presenter Consensus working group believe it would be beneficial if all national health agencies, institutions, and researchers were able to implement this definition (either on its own or alongside their own preferred definition) when reporting surveillance or research data relating to late presentation of HIV infection.
Published: 2010

26. Optimal HIV testing and earlier care: the way forward in Europe

Author: T Coenen, Jeffrey V. Lazarus, Jens D Lundgren, and Srdan Matic
Subjects: Male, medicine.medical_specialty, Mandatory Testing, Human immunodeficiency virus (HIV), HIV Infections, Hiv testing, medicine.disease_cause, World Health Organization, World health, Acquired immunodeficiency syndrome (AIDS), Multidisciplinary approach, Environmental protection, Epidemiology, Medicine, Humans, Pharmacology (medical), business.industry, Health Policy, virus diseases, AIDS Serodiagnosis, European region, medicine.disease, Europe, Infectious Diseases, Family medicine, HIV-1, Female, business, Psychosocial
Abstract: The articles in this supplement were developed from a recent pan-European conference entitled ‘HIV in Europe 2007: Working together for optimal testing and earlier care’, which took place on 26–27 November in Brussels, Belgium. The conference, organized by a multidisciplinary group of experts representing advocacy, clinical and policy areas of the HIV field, was convened in an effort to gain a common understanding on the role of HIV testing and counselling in optimizing diagnosis and the need for earlier care. Key topics discussed at the conference and described in the following articles include: current barriers to HIV testing across Europe, trends in the epidemiology of HIV in the region, problems associated with undiagnosed infection and the psychosocial barriers impacting on testing. The supplement also provides a summary of the World Health Organization's recommendations for HIV testing in Europe and an outline of an indicator disease-guided approach to HIV testing proposed by a committee of experts from the European AIDS Clinical Society (EACS). We hope that consideration of the issues discussed in this supplement will help to shift the HIV field closer towards our ultimate goal: provision of optimal HIV testing and earlier care across the whole of the European region.
Published: 2008

27. [HIV should not become a notifiable disease]

Author: T, Coenen
Subjects: Prevalence, Humans, HIV Infections, Disease Notification, Sentinel Surveillance, Netherlands
Abstract: There is a need for effective strategies in HIV control. However, there is no evidence that making HIV a notifiable disease will contribute to more effective prevention. Making HIV a notifiable disease does not result in more HIV testing and it may even hamper the current proactive testing policy. Moreover, it does not contribute to better surveillance as the current HIV monitoring system provides excellent data on the state of the epidemic. In conclusion, making HIV a notifiable disease should not be introduced.
Published: 2008

28. Sexually transmitted infection health-care seeking behaviour in the Netherlands: General practitioner attends to the majority of sexually transmitted infection consultations

Author: François G. Schellevis, Patrick J E Bindels, Theo G. M. Sandfort, Jan E. A. M. van Bergen, Jan J. Kerssens, Ton T. Coenen, General practice, EMGO - Quality of care, VU University medical center, Other departments, APH - Amsterdam Public Health, and Other Research
Subjects: Adult, Male, Sexually transmitted disease, Health Knowledge, Attitudes, Practice, medicine.medical_specialty, Adolescent, Sexually Transmitted Diseases, Dermatology, Primary care, urologic and male genital diseases, Risk Factors, Humans, Medicine, Pharmacology (medical), Health care seeking, Psychiatry, Aged, Netherlands, Reproductive health, business.industry, Data Collection, Public health, Public Health, Environmental and Occupational Health, Middle Aged, Patient Acceptance of Health Care, Pays bas, Infectious Diseases, General practice, Female, Family Practice, business
Abstract: Health-care seeking behaviour for sexually transmitted infection (STI)-related symptoms is not well known in the Netherlands. Within the framework of a large representative study, the second National Survey of General Practice (NIVEL 2001), 9687 persons aged 18 years and older were interviewed about their STI and STI-related health-care seeking behaviour. In total, 1.2% of the interviewees reported STI-related symptoms in the past year (18–24 years: 5%). A (lifetime) history of STI was reported by 2.7% (18–44 years: 4%). In all, 63% of interviewees visited their general practitioner (GP) for these complaints; 20% went to an STI-clinic and/or municipal public health services and 8% to a different care-provider. A total of 9% did not undertake any action. The majority of persons with STI-related symptoms in the Netherlands visit the GP. Reported history of STI-related symptoms was twice lower in the Netherlands compared with the UK National Sexual Health Survey. Appropriate attention for sexual health in primary care is needed.
Published: 2007
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29. Prevalence of urogenital Chlamydia trachomatis infections in the Netherlands suggests selective screening approaches. Results from the PILOT CT Population Study

Author: J, van Bergen, H, Götz, J H, Richardus, C, Hoebe, J, Broer, and T, Coenen
Subjects: Adult, Male, Rural Population, Adolescent, Urban Population, Research, Chlamydia Infections, Female Urogenital Diseases, Male Urogenital Diseases, Risk Factors, Surveys and Questionnaires, Prevalence, Humans, Mass Screening, Female, Netherlands
Abstract: Chlamydia trachomatis screening is being considered in the Netherlands, but policy recommendations are hampered by the lack of population-based data. We studied the prevalence of chlamydia infection in 15-29-year-old women and men in a national representative sample of 21,000 inhabitants of rural and urban areas in the Netherlands. Of this sample, 41% responded by sending in urine and an answered questionnaire, while 11% returned a refusal card. The overall prevalence of chlamydia infection was 2.0% (CI: 1.7-2.3); 2.5% (CI: 2.0-3.0) in women and 1.5% (1.1-1.8) in men. Chlamydia prevalence was significantly greater in very highly urbanized areas (3.2%, CI: 2.4-4.0) compared to rural areas (0.6%, CI: 0.1-1.1). In very highly urbanized areas the greatest prevalence was found among 15-19-year-old women (4.3%) and among 25-29-year-old men (4.2%). A risk profile could be determined and a prediction rule was developed. These data suggest that nationwide systematic screening is not indicated in the Netherlands and that targeted approaches are a better option. Roll-out of selective screening is recommended.
Published: 2006

30. A fast method to study the secretory activity of neuroendocrine cells at the ultrastructural level

Author: Gerard J. M. Martens, H. P. M. Geurts, F. Van Herp, G. J. A. Janssen, and T. Coenen
Subjects: Histology, Cryoprotectant, Field emission scanning electron microscopy, Endoplasmic reticulum, Molecular Animal Physiology, Cryoelectron Microscopy, Xenopus, Biology, biology.organism_classification, Neurosecretory Systems, Pathology and Forensic Medicine, Cell biology, Xenopus laevis, Ultrastructure, Microscopy, Electron, Scanning, Animals, Freeze Fracturing
Abstract: Summary Cryo field emission scanning electron microscopy (cryo-FE-SEM) is a versatile technique that allows the investigation of the three-dimensional organization of cells at the ultrastructural level over a wide range of magnifications. Unfortunately, cryopreparation of the specimens for this technique remains cumbersome, in particular because ice crystal formation must be prevented during freezing. Here we report that a light prefixation with glutaraldehyde and incubation in glycerol as cryoprotectant or a high-pressure freezing approach are both excellent procedures for cryopreparation of animal cells to be used in combination with cryo-FE-SEM. Using the proopiomelanocortin-producing intermediate pituitary melanotrope cells of Xenopus laevis as a physiologically inducible neuroendocrine system, we compared the ultrastructural characteristics of inactive and hyperactive neuroendocrine cells. The overall quality of the ultrastructural images was comparable for the two cryopreparation procedures, although some fine structures were better conserved using high-pressure freezing. Melanotrope cells in a secretory inactive state contained numerous storage granules and a poorly developed endoplasmic reticulum (ER), while large amounts of rough ER were present in hyperactive cells. Thus, the cryo-FE-SEM approach described here allows a fast ultrastructural study on the secretory activity of neuroendocrine cells.
Published: 2005

31. Prevalence of urogenital Chlamydia trachomatis increases significantly with level of urbanisation and suggests targeted screening approaches: results from the first national population based study in the Netherlands

Author: J E A M van Bergen, A J T Coenen, J. Broer, Hannelore M Götz, Christian J. P. A. Hoebe, J. H. Richardus, Public Health, and Other departments
Subjects: Adult, Male, Sexually transmitted disease, medicine.medical_specialty, Pediatrics, Adolescent, Ethnic group, Chlamydia trachomatis, Dermatology, urologic and male genital diseases, Lower risk, medicine.disease_cause, Polymerase Chain Reaction, Condoms, Epidemiology, Prevalence, Humans, Mass Screening, Medicine, Chlamydia, Netherlands, business.industry, Public health, Urban Health, Chlamydia Infections, Patient Acceptance of Health Care, medicine.disease, female genital diseases and pregnancy complications, Infectious Diseases, Regression Analysis, Female, Rural area, business, Demography
Abstract: Objectives: Chlamydia trachomatis (Chlamydia) is the most prevalent sexually transmitted bacterial infection and can cause considerable reproductive morbidity in women. Chlamydia screening programmes have been considered but policy recommendations are hampered by the lack of population based data. This paper describes the prevalence of Chlamydia in 15–29 year old women and men in rural and urban areas, as determined through systematic population based screening organised by the Municipal Public Health Services (MHS), and discusses the implications of this screening strategy for routine implementation. Methods: Stratified national probability survey according to “area address density” (AAD). 21 000 randomly selected women and men in four regions, aged 15–29 years received a home sampling kit. Urine samples were returned by mail and tested by polymerase chain reaction (PCR). Treatment was via the general practitioner, STI clinic, or MHS clinic. Results: 41% (8383) responded by sending in urine and questionnaire. 11% (2227) returned a refusal card. Non-responders included both higher and lower risk categories. Chlamydia prevalence was significantly lower in rural areas (0.6%, 95% CI 0.1 to 1.1) compared with very highly urbanised areas (3.2%, 95% CI 2.4 to 4.0). Overall prevalence was 2.0% (95% CI 1.7 to 2.3): 2.5% (95% CI 2.0 to 3.0%) in women and 1.5% (95% CI 1.1 to 1.8) in men. Of all cases 91% were treated. Infection was associated with degree of urbanisation, ethnicity, number of sex partners, and symptoms. Conclusion: This large, population based study found very low prevalence in rural populations, suggesting that nationwide systematic screening is not indicated in the Netherlands and that targeted approaches are a better option. Further analysis of risk profiles will contribute to determine how selective screening can be done.
Published: 2005

32. Continued increase of sexually transmitted infections in the Netherlands

Author: M G van Veen, M J W van de Laar, and T Coenen
Published: 2003
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33. Differential frequency-dependent delay from the pulsar magnetosphere

Author: Jason W. T. Hessels, Tim Hassall, K. Zagkouris, Patrick Weltevrede, M. A. Garrett, Wilfred Frieswijk, F. de Gasperin, Y. Tang, P. Maat, Martin Bell, Jochen Eislöffel, R. Vermeulen, M. J. Norden, George Heald, Charlotte Sobey, F. Batejat, Chiara Ferrari, Jean-Mathias Griessmeier, James Miller-Jones, Ashish Asgekar, Mark J. Bentum, John McKean, Matthias Hoeft, Michael W. Wise, Gianni Bernardi, Heino Falcke, Michael Kramer, M. Pilia, R. J. van Weeren, M. Serylak, Annalisa Bonafede, C. Tasse, Harvey Butcher, Richard Fallows, J. W. Broderick, A. Alexov, J.-P. de Reijer, V. I. Kondratiev, P. Zarka, M. Pandey-Pommier, Stefan J. Wijnholds, E. Juette, A. W. Gunst, B. Ciardi, Philip Best, Rob Fender, A. Noutsos, Sarod Yatawatta, T. Coenen, H. J. A. Röttgering, M. Kuniyoshi, Ben Stappers, A. Karastergiou, W. Reich, A. G. Polatidis, Olaf Wucknitz, Evan Keane, S. Duscha, F. Breitling, J. Sluman, Roberto Pizzo, Marcus Brüggen, J. van Leeuwen, Hassall, T.E., Stappers, B.W., Weltevrede, P., Hessels, J.W.T., Alexov, A., Coenen, T., Karastergiou, A., Kramer, M., Keane, E.F., Kondratiev, V.I., Van Leeuwen, J., Noutsos, A., Pilia, M., Serylak, M., Sobey, C., Zagkouris, K., Fender, R., Bell, M.E., Broderick, J., Eislöffel, J., Falcke, H., Grießmeier, J.-M., Kuniyoshi, M., Miller-Jones, J.C.A., Wise, M.W., Wucknitz, O., Zarka, P., Asgekar, A., Batejat, F., Bentum, M.J., Bernardi, G., Best, P., Bonafede, A., Breitling, F., Brüggen, M., Butcher, H.R., Ciardi, B., De Gasperin, F., De Reijer, J.-P., Duscha, S., Fallows, R.A., Ferrari, C., Frieswijk, W., Garrett, M.A., Gunst, A.W., Heald, G., Hoeft, M., Juette, E., Maat, P., McKean, J.P., Norden, M.J., Pandey-Pommier, M., Pizzo, R., Polatidis, A.G., Reich, W., Röttgering, H., Sluman, J., Tang, Y., Tasse, C., Vermeulen, R., Van Weeren, R.J., Wijnholds, S.J., Yatawatta, S., High Energy Astrophys. & Astropart. Phys (API, FNWI), University of Southampton, Jodrell Bank Centre for Astrophysics, University of Manchester [Manchester], University of Amsterdam [Amsterdam] (UvA), Netherlands Institute for Radio Astronomy (ASTRON), Oxford Astrophysics, University of Oxford [Oxford], Max-Planck-Institut für Radioastronomie (MPIFR), Unité Scientifique de la Station de Nançay (USN), Centre National de la Recherche Scientifique (CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire des Sciences de l'Univers en région Centre (OSUC), Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Université d'Orléans (UO), Laboratoire de Physique et Chimie de l'Environnement et de l'Espace (LPC2E), Observatoire des Sciences de l'Univers en région Centre (OSUC), Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS)-Centre National d’Études Spatiales [Paris] (CNES), Thüringer Landessternwarte Tautenburg (TLS), Radboud university [Nijmegen], Astronomical Institute Anton Pannekoek (AI PANNEKOEK), Argelander-Institut für Astronomie (AlfA), Rheinische Friedrich-Wilhelms-Universität Bonn, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Onsala Space Observatory (OSO), Chalmers University of Technology [Göteborg], Laboratoire de Physique Nucléaire et de Hautes Énergies (LPNHE), Centre National de la Recherche Scientifique (CNRS)-Université Paris Diderot - Paris 7 (UPD7)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Pierre et Marie Curie - Paris 6 (UPMC), University of Edinburgh, Jacobs University [Bremen], Leibniz-Institut für Astrophysik Potsdam (AIP), Universität Hamburg (UHH), Max Planck Institute for Astrophysics, Max-Planck-Gesellschaft, Kapteyn Astronomical Institute [Groningen], University of Groningen [Groningen], Joseph Louis LAGRANGE (LAGRANGE), Université Côte d'Azur (UCA)-Université Nice Sophia Antipolis (... - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Observatoire de la Côte d'Azur, Université Côte d'Azur (UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS), Leiden Observatory [Leiden], Universiteit Leiden [Leiden], Ruhr-Universität Bochum [Bochum], Centre de Recherche Astrophysique de Lyon (CRAL), École normale supérieure - Lyon (ENS Lyon)-Université Claude Bernard Lyon 1 (UCBL), Université de Lyon-Université de Lyon-Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS), ANR-09-JCJC-0001,OPALES(2009), European Project: 224838,EC:FP7:PEOPLE,FP7-PEOPLE-2007-4-3-IRG,PULSARS WITH LOFAR(2008), European Project: 267697,EC:FP7:ERC,ERC-2010-AdG_20100224,4PI-SKY(2011), Astronomy, University of Oxford, Université Paris sciences et lettres (PSL)-Université d'Orléans (UO)-Centre National de la Recherche Scientifique (CNRS), Radboud University [Nijmegen], Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut National de Physique Nucléaire et de Physique des Particules du CNRS (IN2P3)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Université Nice Sophia Antipolis (1965 - 2019) (UNS), COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de la Côte d'Azur, COMUE Université Côte d'Azur (2015-2019) (COMUE UCA)-Université Côte d'Azur (UCA)-Université Côte d'Azur (UCA)-Centre National de la Recherche Scientifique (CNRS), Universiteit Leiden, École normale supérieure de Lyon (ENS de Lyon)-Université Claude Bernard Lyon 1 (UCBL), and Université de Lyon-Université de Lyon-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)
Subjects: IR-89517, POLARIZATION, stellar magnetism, Astronomy, EWI-24496, Magnetosphere, FOS: Physical sciences, Astrophysics, 01 natural sciences, RADIO PULSARS, Pulsar, 0103 physical sciences, Differential (infinitesimal), 010303 astronomy & astrophysics, Telescope, Solar and Stellar Astrophysics (astro-ph.SR), Physics, High Energy Astrophysical Phenomena (astro-ph.HE), DRIFTING SUBPULSES, STABILITY, 010308 nuclear & particles physics, Oscillation, [SDU.ASTR.SR]Sciences of the Universe [physics]/Astrophysics [astro-ph]/Solar and Stellar Astrophysics [astro-ph.SR], Astronomy and Astrophysics, Observable, telescopes, LOFAR, PROFILES, Astronomy and Astrophysic, METIS-302712, Pulse (physics), Pulsars: individual: PSR B0809+74, MODEL, stellar pulsations, Pulsars: general, Astrophysics - Solar and Stellar Astrophysics, Space and Planetary Science, ComputingMethodologies_DOCUMENTANDTEXTPROCESSING, pulsars, stellar rotation, PSR B0809+74, RADIATION, Longitude, Astrophysics - High Energy Astrophysical Phenomena, EMISSION, stellar atmospheres
Abstract: Some radio pulsars show clear drifting subpulses, in which subpulses are seen to drift in pulse longitude in a systematic pattern. Here we examine how the drifting subpulses of PSR B0809+74 evolve with time and observing frequency. We show that the subpulse period (P3) is constant on timescales of days, months and years, and between 14-5100 MHz. Despite this, the shapes of the driftbands change radically with frequency. Previous studies have concluded that, while the subpulses appear to move through the pulse window approximately linearly at low frequencies (< 500 MHz), a discrete step of 180 degrees in subpulse phase is observed at higher frequencies (> 820 MHz) near to the peak of the average pulse profile. We use LOFAR, GMRT, GBT, WSRT and Effelsberg 100-m data to explore the frequency-dependence of this phase step. We show that the size of the subpulse phase step increases gradually, and is observable even at low frequencies. We attribute the subpulse phase step to the presence of two separate driftbands, whose relative arrival times vary with frequency - one driftband arriving 30 pulses earlier at 20 MHz than it does at 1380 MHz, whilst the other arrives simultaneously at all frequencies. The drifting pattern which is observed here cannot be explained by either the rotating carousel model or the surface oscillation model, and could provide new insight into the physical processes happening within the pulsar magnetosphere., 10 pages, 6 figures, accepted for publication in Astronomy and Astrophysics
Published: 2013
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34. Localization of messenger RNAs encoding crustacean hyperglycemic hormone and gonad inhibiting hormone in the X-organ sinus gland complex of the lobster Homarus americanus

Author: A.M. Laverdure, F. Van Herp, Dominique P.V. de Kleijn, T. Coenen, and Cornelis P. Tensen
Subjects: Male, medicine.medical_specialty, animal structures, Gonad, Invertebrate Hormones, Molecular Sequence Data, Nerve Tissue Proteins, In situ hybridization, Polymerase Chain Reaction, Arthropod Proteins, Internal medicine, Gene expression, medicine, Animals, Amino Acid Sequence, RNA, Messenger, Cloning, Molecular, In Situ Hybridization, Homarus, Messenger RNA, biology, Base Sequence, General Neuroscience, fungi, RNA, DNA, RNA Probes, biology.organism_classification, Neurosecretory Systems, Cell biology, Nephropidae, Blotting, Southern, Endocrinology, medicine.anatomical_structure, nervous system, Oligodeoxyribonucleotides, Hormone receptor, Female, Vitellogenesis, Carrier Proteins
Abstract: The localization of messenger RNAs encoding the crustacean hyperglycemic hormone, involved in regulation of carbohydrate metabolism and the gonad inhibiting hormone, which inhibits vitellogenesis, was studied in the eyestalk of the lobster Homarus americanus using complementary RNA probes for in situ hybridization. For the detection of gonad inhibiting hormone messenger RNA, we cloned and sequenced a partial complementary DNA encoding lobster gonad inhibiting hormone and for crustacean hyperglycemic hormone messenger RNA detection an available complementary DNA was used. This approach reveals that there is a frequent but inconsistent cellular co-localization of the two neurohormones. Furthermore, our data show that male lobsters contain an equal number of neuroendocrine gonad inhibiting hormone cells as female lobsters. An additional study, involving the use of in situ hybridization in combination with immunocytochemistry, shows that the synthetic activity of the crustacean hyperglycemic hormone- and gonad inhibiting hormone-producing cells can be followed at the messenger RNA as well as the protein level. This reveals that when strong immunostaining is present, the messenger RNA staining is usually weak or absent and vice versa. In conclusion, the presence of cells, containing only gonad inhibiting hormone messenger RNA or only crustacean hyperglycemic hormone messenger RNA, indicates that lobster crustacean hyperglycemic hormone and gonad inhibiting hormone originate from two different precursors. Co-localization of the two neurohormone messenger RNAs confirms the co-localization at the peptidergic level found by immunocytochemistry and thus these findings were not due to cross-reactions between the two antisera.(ABSTRACT TRUNCATED AT 250 WORDS)
Published: 1992

35. Business Subsidies and the Dormant Commerce Clause

Author: Dan T. Coenen
Subjects: Tax break, Commerce Clause, Tax deduction, Economics, Tariff, Subsidy, Federalism, Law, Law and economics, Dormant Commerce Clause, Supreme court
Abstract: In this article, I seek to respond to the Court's overture with a treatment of of subsidies under the dormant Commerce Clause that moves progressively from the general to the specific. Part I examines key Supreme Court cases to show that the basic question of whether state business subsidies are constitutional remains open and important. Part II then turns to how that question should be resolved, focusing on whether subsidies are fairly distinguishable from ostensibly equivalent, and concededly unlawful, discriminatory tax relief. The thrust of Part II is that both precedent and policy support the traditional, pre-West Lynn Creamer" view that state subsidies almost always comport with the dormant Commerce Clause principle. In particular, Part II emphasizes that four considerations-rooted in form, fairness, federalism, and political processes-render subsidies less threatening to Commerce Clause values than economically comparable tax deductions, credits, and exemptions. Part III then addresses the major question that Part II leaves open: How should courts distinguish the ordinary subsidy that is constitutional from the exceptional subsidy that is not? Part III suggests that none of the opinions in West Lynn Creamery-in which an exceptional subsidy was struck downoffers much useful guidance on this critical question. As a result, Part IV offers an alternative analytical framework for distinguishing the constitutional grant-in-aid from the unconstitutional assault upon our "federal free trade unit."' In essence, this proposal calls upon courts to draw the line between permissible and impermissible subsidies by focusing on the same four factors already identified in Part II to distinguish ordinary subsidies from discriminatory tax breaks as a general matter. Accordingly, Part IV advocates an approach that asks whether the challenged subsidy-because of its linkage to a particular tax-shares the essential constitutional defects of a discriminatory tax break. Using the four factors, courts would consider the following: (1) whether, consistent with conventional property-based notions of fairness, the subsidy merely permits state residents to reap where they have sown; (2) whether invalidation of the subsidy frustrates the state's federalism based interest in experimenting with responses to distinctive local needs; (3) whether the same political dynamics that unduly encourage adoption and retention of discriminatory tax relief (i.e., reduced visibility, heightened risks of entrenchment, lowered administrative costs, and the like) mark the challenged subsidy scheme; and (4) whether the subsidy is part of a program that resembles in form a protective tariff or kindred types of unconstitutional discriminatory taxation.
Published: 1998
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36. Technical efficiency of high technology medicine

Author: J. F. A. Spangenberg, J. Winter, J. De Vreese, J.H.R. Van De Poel, D. Reis Miranda, G. Iappichino, T. Coenen, J. E. Spangenberg, and S. Van De Vathorst
Subjects: Incentive, Strategy and Management, Intensive care, Critical illness, Operations management, Business, Management Science and Operations Research, Phase (combat), Management control system
Abstract: Intensive care units (ICUs) are classic examples of high technology medicine. The ICU has become an essential step in the clinical management of patients passing through a phase of critical illness, However, the costs are extremely h9gh (1% of GNP in the USA), whereas it has not ben adeqyately demonstrated that routine admission to intensive care is associated with an increase in survival rate and a decrease in morbidity. Consequently, intensive care is a logical arena in which to encourage more efficient use. The paper focuses on determinates of the technical efficiency of the ICU. Technical efficiency can only be ensured when the ICU is conceived as a responsibility centre where inputs, throughputs and outputs are measured. The reaponsbility centre in characterized by management control, which is dependent on reliable information regarding incentives and constraints of ICU performance. On the basis of the medical and economic literature, conjectures are made on determinants of ICU performance. In additi...
Published: 1989
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37. [Does bronchoalveolar lavage modify the milieu in the alveolus?]

Author: T, Joka, J A, Nakhosteen, U, Obertacke, J, Herrmann, T, Coenen, M, Brand, M, Jochum, G, Zilow, A, Dwenger, and E, Kreuzfelder
Subjects: Pulmonary Alveoli, Leukocyte Count, Phagocytosis, Risk Factors, Humans, Bronchoalveolar Lavage Fluid, Acute-Phase Proteins
Published: 1988

38. The LOFAR transients key project

Author: Michael W. Wise, Peter G. Jonker, Ben Stappers, Philippe Zarka, Jean-Mathias Griessmeier, Robert Braun, Michiel van Haarlem, Rob Fender, James Miller-Jones, Heino Falcke, Bart Scheers, Rudy Wijnands, T. Coenen, Ralph A. M. J. Wijers, Rachel A. Osten, J. Masters, Casey J. Law, Sera Markoff, H. Spreeuw, John D. Swinbank, C. Vogt, Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA), Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris, Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS), Physique des plasmas, and Université Paris sciences et lettres (PSL)-Université Paris sciences et lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS)-Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris
Subjects: Physics, Astrophysics (astro-ph), Key (cryptography), Astronomy, FOS: Physical sciences, LOFAR, Astrophysics, [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph]
Abstract: LOFAR, the Low Frequency Array, is a new radio telescope under construction in the Netherlands, designed to operate between 30 and 240 MHz. The Transients Key Project is one of the four Key Science Projects which comprise the core LOFAR science case. The remit of the Transients Key Project is to study variable and transient radio sources detected by LOFAR, on timescales from milliseconds to years. This will be achieved via both regular snapshot monitoring of historical and newly-discovered radio variables and, most radically, the development of a `Radio Sky Monitor' which will survey a large fraction of the northern sky on a daily basis., Comment: Accepted for publication in the proceedings of VI Microquasar Workshop: Microquasars and Beyond, 18-22 September 2006, Como (Italy), ed: T. Belloni (2006)

39. Early Pulsar Observations with LOFAR

Author: Ben Stappers, Tim Hassall, J. van Leeuwen, Michael Kramer, V. I. Kondratiev, A. Noutsos, A. Karastergiou, Patrick Weltevrede, J. D. Mol, Jason W. T. Hessels, T. Coenen, A. Alexov, and High Energy Astrophys. & Astropart. Phys (API, FNWI)
Subjects: Physics, Pulsar, Astrophysics::Instrumentation and Methods for Astrophysics, Astronomy, Square (unit), Astrophysics::Cosmology and Extragalactic Astrophysics, LOFAR, Radio astronomy
Abstract: This contribution to the proceedings of "A New Golden Age for Radio Astronomy" is simply intended to give some of the highlights from pulsar observations with LOFAR at the time of its official opening: June 12th, 2010. These observations illustrate that, though LOFAR is still under construction and astronomical commissioning, it is already starting to deliver on its promise to revolutionize radio astronomy in the low-frequency regime. These observations also demonstrate how LOFAR has many "next-generation" capabilities, such as wide-field multi-beaming, that will be vital to open a new Golden Age in radio astronomy through the Square Kilometer Array and its precursors.

40. Spatially resolved luminescence properties of non- and semi-polar InGaN quantum wells on GaN microrods.

Author: J Dühn, M Schowalter, B Gerken, K Müller-Caspari, T Mehrtens, A Rosenauer, J Gutowski, K Sebald, C Tessarek, M Heilmann, S Christiansen, and T Coenen
Subjects: INDIUM gallium nitride, QUANTUM wells, NANORODS, PHOTOLUMINESCENCE, CATHODOLUMINESCENCE
Abstract: Spatially resolved emission properties of InGaN/GaN quantum wells on the facets of microrods are analyzed by means of photoluminescence and cathodoluminescence measurements. We observe strongly localized emissions of the non- and semi-polar InGaN quantum wells from the top part of the microrods, suggesting optical emitters of high efficiency. The quantum wells are characterized by transmission electron microscopy measurements with respect to their indium composition and thickness. Those wells oriented in non- and semi-polar directions possess high In concentrations as well as low internal polarization fields which makes these directions excellent candidates for InGaN quantum well emitters. These investigations show that the applied microrod growth concept is an effective method to realize high quality InGaN quantum wells on GaN facets oriented in non- and semi-polar directions which makes optoelectronic emitters in the green gap region feasible. [ABSTRACT FROM AUTHOR]
Published: 2018
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41. Untangling the Market-Participant Exemption to the Dormant Commerce Clause

Author: Dan T. Coenen
Subjects: Commerce Clause, Political science, media_common.quotation_subject, Market participant, Doctrine, Federalism, Constitutional law, Abstention doctrine, Law, Supreme court, Dormant Commerce Clause, media_common, Law and economics
Abstract: There is no theme more familiar to constitutional law than the clash between federal power and state autonomy. The history of that struggle reveals, by and large, a long losing battle by the states. Over the years, the Supreme Court has recognized far-reaching congressional powers, rebuffed efforts to rein them in through use of the tenth amendment, and saddled the states with every significant restraint imposed by the Bill of Rights. From time to time, however, the currents of constitutional doctrine run in favor of local control. In recent years, for example, the Court has stemmed the tide toward constitutionalizing the law of criminal procedure, and cut down federal judicial authority through development of the abstention doctrine and state-favoring constructions of the eleventh amendment. This article focuses on another important vehicle through which the modern Court has moved to protect local prerogatives: the market-participant exemption to the dormant commerce clause.The core of the Court's dormant commerce clause jurisprudence is well-settled: "The commerce clause, by its own force, prohibits discrimination against interstate commerce, whatever its form or method..." Over the past two decades, however, the Court has lifted this prohibition when states act as "market participants" rather than as "market regulators." Invoking this distinction, the Court has shielded from commerce clause attack blatant favoritism of local interests when a state or municipality buys printing services, sells cement, purchases goods, or hires workers.This article explores the market-participant rule. Part I traces the rule's evolution and shows how it has proven less rigid than some initially feared. Part II probes the roots of the rule by challenging justifications for it suggested by other observers. Part III offers an alternative theory of the market-participant doctrine, arguing in particular that it rests on a cluster of rationales that properly have led the Court to uphold marketplace preferences as the "general rule." Part IV builds on Part III to advance a new, four-part framework for evaluating market-participant issues. Part V then uses that framework to apply the market-participant rule to nine key categories of cases. This article rejects an all-or-nothing approach to these cases, advocating instead a sensitive application of the market-participant rule in light of its underlying justifications.Many observers have attacked the market-participant rule. this article seeks to show that these challenges are misplaced. The Court's market-participation decisions reflect a sound, if complex, accommodation of competing constitutional values. This article lays bare those values and details the course they suggest courts should follow in deciding future market-participation cases.
Published: 1989
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42. Cathodoluminescence emission and electron energy loss absorption from a 2D transition metal dichalcogenide in van der Waals heterostructures.

Author: Bonnet N, Baaboura J, Castioni F, Woo SY, Ho CH, Watanabe K, Taniguchi T, Tizei LHG, and Coenen T
Abstract: Nanoscale variations of optical properties in transition metal dichalcogenide (TMD) monolayers can be explored with cathodoluminescence (CL) and electron energy loss spectroscopy (EELS) using electron microscopes. To increase the CL emission intensity from TMD monolayers, the MoSe 2 flakes are encapsulated in hexagonal boron nitride (hBN), creating van der Waals (VdW) heterostructures. Until now, the studies have been exclusively focused on scanning transmission electron microscopy (STEM-CL) or scanning electron microscopy (SEM-CL), separately. Here, we present results, using both techniques on the same sample, thereby exploring a large acceleration voltage range. We correlate the CL measurements with STEM-EELS measurements acquired with different energy dispersions, to access both the low-loss region at ultra-high spectral resolution, and the core-loss region. This provides information about the weight of the various absorption phenomena including the direct TMD absorption, the hBN interband transitions, the hBN bulk plasmon, and the core losses of the atoms present in the heterostructure. The S(T)EM-CL measurements from the TMD monolayer only show emission from the A exciton. Combining the STEM-EELS and S(T)EM-CL measurements, we can reconstruct different decay pathways leading to the A exciton CL emission. The comparison with SEM-CL shows that this is also a good technique for TMD heterostructure characterization, where the reduced demands on sample preparation are appealing. To demonstrate the capabilities of SEM-CL imaging, we also measured on a SiO 2 /Si substrate, quintessential in the sample preparation of two-dimensional materials, which is electron-opaque and can only be measured in SEM-CL. The CL-emitting defects of SiO 2 make this substrate challenging to use, but we demonstrate that this background can be suppressed by using lower electron energy., (© 2024 IOP Publishing Ltd.)
Published: 2024
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43. Modulation of Cathodoluminescence by Surface Plasmons in Silver Nanowires.

Author: Liu ACY, Davis TJ, Coenen T, Hari S, Voortman LM, Xu Z, Yuan G, Ballard PM, Funston AM, and Etheridge J
Abstract: The waveguide modes in chemically-grown silver nanowires on silicon nitride substrates are observed using spectrally- and spatially-resolved cathodoluminescence (CL) excited by high-energy electrons in a scanning electron microscope. The presence of a long-range, travelling surface plasmon mode modulates the coupling efficiency of the incident electron energy into the nanowires, which is observed as oscillations in the measured CL with the point of excitation by the focused electron beam. The experimental data are modeled using the theory of surface plasmon polariton modes in cylindrical metal waveguides, enabling the complex mode wavenumbers and excitation strength of the long-range surface plasmon mode to be extracted. The experiments yield insight into the energy transfer mechanisms between fast electrons and coherent oscillations in surface charge density in metal nanowires and the relative amplitudes of the radiative processes excited in the wire by the electron., (© 2023 The Authors. Small published by Wiley-VCH GmbH.)
Published: 2023
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44. Development of tailored splice-switching oligonucleotides for progressive brain disorders in Europe: development, regulation, and implementation considerations.

Author: Aartsma-Rus A, van Roon-Mom W, Lauffer M, Siezen C, Duijndam B, Coenen-de Roo T, Schüle R, Synofzik M, and Graessner H
Subjects: Humans, Oligonucleotides, Antisense genetics, Oligonucleotides, Antisense therapeutic use, Brain, Europe, Oligonucleotides genetics, Oligonucleotides therapeutic use, Brain Diseases drug therapy
Abstract: Splice-modulating antisense oligonucleotides (ASOs) offer treatment options for rare neurological diseases, including those with very rare mutations, where patient-specific, individualized ASOs have to be developed. Inspired by the development of milasen, the 1 Mutation 1 Medicine (1M1M) and Dutch Center for RNA Therapeutics (DCRT) aim to develop patient-specific ASOs and treat eligible patients within Europe and the Netherlands, respectively. Treatment will be provided under a named patient setting. Our initiatives benefited from regulatory advice from the European Medicines Agency (EMA) with regard to preclinical proof-of-concept studies, safety studies, compounding and measuring benefit and safety in treated patients. We here outline the most important considerations from these interactions and how we implemented this advice into our plan to develop and treat eligible patients within Europe., (© 2023 Aartsma-Rus et al.; Published by Cold Spring Harbor Laboratory Press for the RNA Society.)
Published: 2023
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45. Photon Statistics of Incoherent Cathodoluminescence with Continuous and Pulsed Electron Beams.

Author: Solà-Garcia M, Mauser KW, Liebtrau M, Coenen T, Christiansen S, Meuret S, and Polman A
Abstract: Photon bunching in incoherent cathodoluminescence (CL) spectroscopy originates from the fact that a single high-energy electron can generate multiple photons when interacting with a material, thus, revealing key properties of electron-matter excitation. Contrary to previous works based on Monte Carlo modeling, here we present a fully analytical model describing the amplitude and shape of the second order autocorrelation function ( g (2) (τ)) for continuous and pulsed electron beams. Moreover, we extend the analysis of photon bunching to ultrashort electron pulses, in which up to 500 electrons per pulse excite the sample within a few picoseconds. We obtain a simple equation relating the bunching strength ( g (2) (0)) to the electron beam current, emitter decay lifetime, pulse duration, in the case of pulsed electron beams, and electron excitation efficiency (γ), defined as the probability that an electron creates at least one interaction with the emitter. The analytical model shows good agreement with the experimental data obtained on InGaN/GaN quantum wells using continuous, ns-pulsed (using beam blanker) and ultrashort ps-pulsed (using photoemission) electron beams. We extract excitation efficiencies of 0.13 and 0.05 for 10 and 8 keV electron beams, respectively, and we observe that nonlinear effects play no compelling role, even after excitation with ultrashort and dense electron cascades in the quantum wells., Competing Interests: The authors declare the following competing financial interest(s): T.C. is an employee and A.P. is the co-founder and co-owner of Delmic BV, a company that produces the cathodoluminescence system that was used in this work., (© 2021 The Authors. Published by American Chemical Society.)
Published: 2021
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46. Correlative cathodoluminescence electron microscopy bioimaging: towards single protein labelling with ultrastructural context.

Author: Keevend K, Coenen T, and Herrmann IK
Subjects: Luminescence, Microscopy, Electron, Prospective Studies, Gold, Metal Nanoparticles
Abstract: The understanding of living systems and their building blocks relies heavily on the assessment of structure-function relationships at the nanoscale. Ever since the development of the first optical microscope, the reliance of scientists across disciplines on microscopy has increased. The development of the first electron microscope and with it the access to information at the nanoscale has prompted numerous disruptive discoveries. While fluorescence imaging allows identification of specific entities based on the labelling with fluorophores, the unlabelled constituents of the samples remain invisible. In electron microscopy on the other hand, structures can be comprehensively visualized based on their distinct electron density and geometry. Although electron microscopy is a powerful tool, it does not implicitly provide information on the location and activity of specific organic molecules. While correlative light and electron microscopy techniques have attempted to unify the two modalities, the resolution mismatch between the two data sets poses major challenges. Recent developments in optical super resolution microscopy enable high resolution correlative light and electron microscopy, however, with considerable constraints due to sample preparation requirements. Labelling of specific structures directly for electron microscopy using small gold nanoparticles (i.e. immunogold) has been used extensively. However, identification of specific entities solely based on electron contrast, and the differentiation from endogenous dense granules, remains challenging. Recently, the use of correlative cathodoluminescence electron microscopy (CCLEM) imaging based on luminescent inorganic nanocrystals has been proposed. While nanometric resolution can be reached for both the electron and the optical signal, high energy electron beams are potentially damaging to the sample. In this review, we discuss the opportunities of (volumetric) multi-color single protein labelling based on correlative cathodoluminescence electron microscopy, and its prospective impact on biomedical research in general. We elaborate on the potential challenges of correlative cathodoluminescence electron microscopy-based bioimaging and benchmark CCLEM against alternative high-resolution correlative imaging techniques.
Published: 2020
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47. Mapping Local Surface Plasmon Modes in a Nanoplasmonic Trimer Using Cathodoluminescence in the Scanning Electron Microscope.

Author: Liu ACY, Lloyd J, Coenen T, and Gómez DE
Abstract: The excitability of local surface plasmon modes in radial trimers composed of gold nanorods was mapped using hyperspectral cathodoluminescence (CL) in the scanning electron microscope. In symmetric trimers, the local plasmon resonances could be excited most effectively at the ends of individual rods. Introducing asymmetry into the structure breaks the degeneracy of the dipole modes and changes the excitability of transverse dipole modes in different directions. CL in the scanning electron microscope has great potential to interrogate individual nanophotonic structures and is a complement to electron energy loss spectroscopy and optical microscopy.
Published: 2020
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48. Improving Translation by Identifying Evidence for More Human-Relevant Preclinical Strategies.

Author: Ritskes-Hoitinga M, Leenaars C, Beumer W, Coenen-de Roo T, Stafleu F, and Meijboom FLB
Abstract: Preclinical animal studies are performed to analyse the safety and efficacy of new treatments, with the aim to protect humans. However, there are questions and concerns about the quality and usefulness of preclinical animal research. Translational success rates vary between 0 and 100%, and no clear relationship has been found with possible predictive factors such as animal species or field of research. Therefore, it is not yet possible to indicate what factors predict successful translation. Translational strategies were therefore discussed at an international conference held in the Netherlands in November 2019, aiming to develop practical guidelines for more robust animal-to-human translation. The conference was organised during the course of a research project funded by the Dutch Research Council (313-99-310), addressing possible solutions for the low translational values that had been published for a multitude of animal studies in human health care. This article provides an overview of the project and the conference discussions. Based on the conference results and the findings from the research project, we define four points of attention that are crucial in the search for improved translational success rates: (a) optimising the methods and design of studies; (b) incorporation of the complexity of the human patient in research; (c) start with the patient rather than existing animal models as the gold standard; and (d) more and better collaboration within the chain from funding to pharmacy. We conclude that this requires improved organization and use of procedures, as well as a change of attitude and culture in research, including a consideration of the translational value of animal-free innovations and human-relevant science.
Published: 2020
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49. A Systematic Review Comparing Experimental Design of Animal and Human Methotrexate Efficacy Studies for Rheumatoid Arthritis: Lessons for the Translational Value of Animal Studies.

Author: Leenaars C, Stafleu F, de Jong D, van Berlo M, Geurts T, Coenen-de Roo T, Prins JB, Kempkes R, Elzinga J, Bleich A, de Vries R, Meijboom F, and Ritskes-Hoitinga M
Abstract: Increased awareness and understanding of current practices in translational research is required for informed decision making in drug development. This paper describes a systematic review of methotrexate for rheumatoid arthritis, comparing trial design between 147 animal and 512 human studies. Animal studies generally included fewer subjects than human studies, and less frequently reported randomisation and blinding. In relation to life span, study duration was comparable for animals and humans, but included animals were younger than included humans. Animal studies often comprised males only (61%), human studies always included females (98% included both sexes). Power calculations were poorly reported in both samples. Analyses of human studies more frequently comprised Chi-square tests, those of animal studies more frequently reported analyses of variance. Administration route was more variable, and more frequently reported in animal than human studies. Erythrocyte sedimentation rate and c-reactive protein were analysed more frequently in human than in animal studies. To conclude, experimental designs for animal and human studies are not optimally aligned. However, methotrexate is effective in treating rheumatoid arthritis in animal models and humans. Further evaluation of the available evidence in other research fields is needed to increase the understanding of translational success before we can optimise translational strategies.
Published: 2020
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50. Electron-Induced State Conversion in Diamond NV Centers Measured with Pump-Probe Cathodoluminescence Spectroscopy.

Author: Solà-Garcia M, Meuret S, Coenen T, and Polman A
Abstract: Nitrogen-vacancy (NV) centers in diamond are reliable single-photon emitters, with applications in quantum technologies and metrology. Two charge states are known for NV centers, NV 0 and NV - , with the latter being mostly studied due to its long electron spin coherence time. Therefore, control over the charge state of the NV centers is essential. However, an understanding of the dynamics between the different states still remains challenging. Here, conversion from NV - to NV 0 due to electron-induced carrier generation is shown. Ultrafast pump-probe cathodoluminescence spectroscopy is presented for the first time, with electron pulses as pump and laser pulses as probe, to prepare and read out the NV states. The experimental data are explained with a model considering carrier dynamics (0.8 ns), NV 0 spontaneous emission (20 ns), and NV 0 → NV - back transfer (500 ms). The results provide new insights into the NV - → NV 0 conversion dynamics and into the use of pump-probe cathodoluminescence as a nanoscale NV characterization tool., Competing Interests: The authors declare no competing financial interest., (Copyright © 2019 American Chemical Society.)
Published: 2020
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