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1.
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2.
  • Maes, S.L., et al. (author)
  • Environmental drivers of increased ecosystem respiration in a warming tundra
  • 2024
  • In: Nature. - : Springer Nature. - 0028-0836 .- 1476-4687. ; 629:8010, s. 105-113
  • Journal article (peer-reviewed)abstract
    • Arctic and alpine tundra ecosystems are large reservoirs of organic carbon. Climate warming may stimulate ecosystem respiration and release carbon into the atmosphere. The magnitude and persistency of this stimulation and the environmental mechanisms that drive its variation remain uncertain. This hampers the accuracy of global land carbon–climate feedback projections. Here we synthesize 136 datasets from 56 open-top chamber in situ warming experiments located at 28 arctic and alpine tundra sites which have been running for less than 1 year up to 25 years. We show that a mean rise of 1.4 °C [confidence interval (CI) 0.9–2.0 °C] in air and 0.4 °C [CI 0.2–0.7 °C] in soil temperature results in an increase in growing season ecosystem respiration by 30% [CI 22–38%] (n = 136). Our findings indicate that the stimulation of ecosystem respiration was due to increases in both plant-related and microbial respiration (n = 9) and continued for at least 25 years (n = 136). The magnitude of the warming effects on respiration was driven by variation in warming-induced changes in local soil conditions, that is, changes in total nitrogen concentration and pH and by context-dependent spatial variation in these conditions, in particular total nitrogen concentration and the carbon:nitrogen ratio. Tundra sites with stronger nitrogen limitations and sites in which warming had stimulated plant and microbial nutrient turnover seemed particularly sensitive in their respiration response to warming. The results highlight the importance of local soil conditions and warming-induced changes therein for future climatic impacts on respiration.
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3.
  • Bergmann, U. C., et al. (author)
  • Production yields of noble-gas isotopes from ISOLDE UCx/graphite targets
  • 2003
  • In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 204, s. 220-224
  • Journal article (peer-reviewed)abstract
    • Yields of He, Ne, Ar, Kr and Xe isotopic chains were measured from UCx/graphite and ThCx/graphite targets at the PSB-ISOLDE facility at CERN using isobaric selectivity achieved by the combination of a plasma-discharge ion source with a water-cooled transfer line. The delay times measured for a UCx/graphite target allow for an extrapolation to the expected yields of very neutron-rich noble gas isotopes, in particular for the "NuPECC reference elements" Ar and Kr, at the next-generation radioactive ion-beam facility EURISOL. (C)2003 Elsevier Science B.V. All rights reserved.
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4.
  • Habs, D., et al. (author)
  • The REX-ISOLDE project
  • 2000
  • In: Hyperfine Interactions. - 0304-3843 .- 1572-9540. ; 129:1-4, s. 43-66
  • Journal article (peer-reviewed)abstract
    • The Radioactive Beam Experiment REX-ISOLDE [1-3] is a pilot experiment at ISOLDE (CERN) testing the new concept of post acceleration of radioactive ion beams by using charge breeding of the ions in a high charge state ion source and the efficient acceleration of the highly charged ions in a short LINAC using modern ion accelerator structures. In order to prepare the ions for the experiments singly charged radioactive ions from the on-line mass separator ISOLDE will be cooled and bunched in a Penning trap, charge bred in an electron beam ion source (EBIS) and finally accelerated in the LINAC. The LINAC consists of a radiofrequency quadrupole (RFQ) accelerator, which accelerates the ions up to 0.3 MeV/u, an interdigital H-type (IH) structure with a final energy between 1.1 and 1.2 MeV/u and three seven gap resonators, which allow the variation of the final energy. With an energy of the radioactive beams between 0.8 MeV/u and 2.2 MeV/u a wide range of experiments in the field of nuclear spectroscopy, astrophysics and solid state physics will be addressed by REX-ISOLDE.
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5.
  • Shergur, J., et al. (author)
  • Decay of Sn-135,Sn-136 isolated by use of a laser ion source and evidence for a more harmonic-oscillator-like nuclear potential
  • 2001
  • In: Nuclear Physics A. - 0375-9474. ; 682, s. 493C-497C
  • Conference paper (peer-reviewed)abstract
    • The use of a resonance ionization laser ion source at CERN/ISOLDE has made it possible to study the decay of very neutron-rich Sn135-137. The decay of Sn-135 is found to populate low-energy levels in Sb-135 via direct beta decay and the first excited state in Sb-134 by beta-delayed neutron emission. The level structure of Sb-135 Will be discussed and a possible signature for a more diffuse nuclear surface considered.
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6.
  • Backlund, Y., et al. (author)
  • Micromachining of Silicon for Thermal and Position-Sensitive Nuclear-Detector Applications
  • 1989
  • In: Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. - : Elsevier BV. - 0168-9002. ; 279:3, s. 555-559
  • Journal article (peer-reviewed)abstract
    • As part of a programme aiming at the development of small nuclear radiation detectors, for example thermal detectors and position sensitive mosaic structures of surface barrier type, a technique for micromachining the detector bodies in silicon has been developed. The technique is based on an anisotropic etching property of a solution, mainly consisting of KOH. The etch rate is strongly orientation dependent with a speed in the 〈100〉 direction about 400 times faster than in the 〈111〉 direction. The major steps in the etching procedure are described and some examples of deep etching in Si are shown.
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8.
  • Coron, N., et al. (author)
  • A Composite Bolometer as a Charged-Particle Spectrometer
  • 1985
  • In: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 314:6006, s. 75-76
  • Journal article (peer-reviewed)abstract
    • The measurement of radioactivity by direct conversion of nuclear radiation into a temperature rise of a calorimeter is as old as nuclear physics itself. As part of a general programme aiming at a determination of the mass of the electron neutrino, we have designed an improved version of a He-cooled composite diamond bolometer with a monolithic germanium thermistor, developed at the Laboratoire de Physique Stellaire et Planetaire (LPSP)1. Our approach, based on an idea by De Rujula2, is to study the shape, near the upper end-point of the internal bremsstrahlung spectrum in electron-capture β decay. The best nucleus for a precise measurement seems to be 163Ho, for which we have determined3 the Q EC value to be 2.83±0.05 keV. A particularly interesting possibility is to use total absorption spectrometry4 (calorimetry), in which the radioactive holmium forms part of the sensitive volume of the detector. With 5–6-MeV α particles impinging on the diamond wafer of the bolometer, a full-width-at-half-maximum (FWHM) of 36 keV was obtained at a temperature of 1.3 K. The theoretical resolution at 100 mK is a few electron-volts, so this new detection technique should give greatly enhanced energy resolution compared with present solid-state conductors based on charge carrier collection.
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9.
  • Farmakis, D., et al. (author)
  • Levosimendan beyond inotropy and acute heart failure: Evidence of pleiotropic effects on the heart and other organs: An expert panel position paper
  • 2016
  • In: International Journal of Cardiology. - : Elsevier BV. - 0167-5273. ; 222, s. 303-312
  • Journal article (peer-reviewed)abstract
    • Levosimendan is a positive inotrope with vasodilating properties (inodilator) indicated for decompensated heart failure (HF) patients with low cardiac output. Accumulated evidence supports several pleiotropic effects of levosimendan beyond inotropy, the heart and decompensated HF. Those effects are not readily explained by cardiac function enhancement and seem to be related to additional properties of the drug such as anti-inflammatory, anti-oxidative and anti-apoptotic ones. Mechanistic and proof-of-concept studies are still required to clarify the underlying mechanisms involved, while properly designed clinical trials are warranted to translate preclinical or early-phase clinical data into more robust clinical evidence. The present position paper, derived by a panel of 35 experts in the field of cardiology, cardiac anesthesiology, intensive care medicine, cardiac physiology, and cardiovascular pharmacology from 22 European countries, compiles the existing evidence on the pleiotropic effects of levosimendan, identifies potential novel areas of clinical application and defines the corresponding gaps in evidence and the required research efforts to address those gaps. © 2016 The Authors
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10.
  • Georg, U., et al. (author)
  • Isotope production comparison at ISOLDE with 1 and 1.4 GeV protons
  • 2002
  • In: Nuclear Physics A. - 0375-9474. ; 701, s. 137C-143C
  • Conference paper (peer-reviewed)abstract
    • The difference in isotope production between 1 and 1.4 GeV proton projectiles was investigated at ISOLDE/CERN during the year 1999. As target materials uranium carbide, thorium carbide, lead and lanthanum oxide were used and the ratio of the measured production yields for the two different projectile energies were determined for isotopes of the elements francium, mercury, thallium, xenon, cesium, krypton, rubidium and neon. A comparison of these experimental results with the predictions from a two-step reaction model Monte-Carlo code shows good agreement. (C) 2002 Elsevier Science B.V. All rights reserved.
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11.
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12.
  • Stroke, H. H., et al. (author)
  • Bolometers as Particle Spectrometers
  • 1986
  • In: IEEE Transactions on Nuclear Science. - 0018-9499. ; 33:1, s. 759-761
  • Journal article (peer-reviewed)
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13.
  • Axelsson, H., et al. (author)
  • Candidates for Electron-Neutrino Mass Measurements - the Case of Kr-81
  • 1988
  • In: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 210:1-2, s. 249-252
  • Journal article (peer-reviewed)abstract
    • The nuclear data of the known candidates for neutrino mass determination by resonant electron-capture beta decay are reviewed. New results are presented for the isotope 81Kr, where the transition to the 276 keV state has been found to have QEC=4.7±0.5 keV and a branching ratio of (3.0±0.2)×10−3
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14.
  • Bennett, J. R. J., et al. (author)
  • Measurements of intense beams of Li-11 from a tantalum foil target
  • 1999
  • In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 155:4, s. 515-517
  • Journal article (peer-reviewed)abstract
    • The yields of Li-11 from a tantalum target, constructed from very thin foils, have been measured at ISOLDE and found to be an order of magnitude greater than those previously measured for a standard roll foil target. The modifications to the existing target designs were based on theoretical modelling calculations. The tantalum foils are 2 mu m thick and the target mass is only one tenth of normal foil targets. (C) 1999 Elsevier Science B.V. All rights reserved.
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15.
  • Bennett, J. R. J., et al. (author)
  • Release studies of a thin foil tantalum target for the production of short-lived radioactive nuclei
  • 2002
  • In: Nuclear Physics A. - 0375-9474. ; 701, s. 327C-333C
  • Conference paper (peer-reviewed)abstract
    • Measurements have been made at ISOLDE, of the release curves and yields of radioactive beams of lithium, sodium and beryllium from a target constructed from 2 pm thick foils. The release curves have been analysed by fitting to a mathematical model to determine the coefficients of diffusion of the particles in the foils and effusion through the target and ionizer at several temperatures. Through a better understanding of the rate of transport of the particles, it is possible to design targets and ionizers with improved yields. This is most important for the rare, short-lived isotopes in which there is considerable interest for physics experiments. This target has demonstrated large increases in the yields of Li-11 and Be-12, in agreement with the predictions of the model. (C) 2002 Elsevier Science B.V. All rights reserved.
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19.
  • Kugler, E., et al. (author)
  • The New Cern-Isolde Online Mass-Separator Facility at the Ps-Booster
  • 1992
  • In: Nuclear Instruments and Methods in Physics Research, Section B: Beam Interactions with Materials and Atoms. - 0168-583X. ; 70:1-4, s. 41-49
  • Journal article (peer-reviewed)abstract
    • The ISOLDE on-line isotope separators have been operated since 1967 at the CERN-SC. This 600 MeV proton synchro-cyclotron had to be shut down in December 1990 after 33 years of service and it was decided to move ISOLDE to a new experimental area. The new on-line mass-separator facility is now under construction at the CERN PS-Booster. This accelerator provides an average current of about 2-mu-A of 1 GeV protons in very short high intensity pulses at low repetition rate. The beam can hit either one of the two target stations, the general purpose separator (GPS), a reconstructed ISOLDE-2 type machine (which can deliver beams simultaneously into three beam lines), and the high resolution separator (HRS), which is essentially the slightly modified ISOLDE-3 separator. The central GPS beam line and the HRS feed a common beam transport system to which most of the experiments will be connected. The new facility will be taken into operation in spring 1992.
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20.
  • Laursen, K. R., et al. (author)
  • An RCT of acute health effects in COPD-patients after passive vape exposure from e-cigarettes
  • 2021
  • In: European Clinical Respiratory Journal. - : Informa UK Limited. - 2001-8525. ; 8:1
  • Journal article (peer-reviewed)abstract
    • Background: E-cigarette use has been shown to have short-term acute effects among active users but less is known of the acute passive effects, particularly among individuals with existing respiratory diseases. Objective: To investigate local and systemic effects of short-term passive vape exposure among patients with mild or moderate chronic obstructive pulmonary disease (COPD). Methods: In a double-blinded crossover study 16 non-smoking COPD-patients (mean age 68) were randomly exposed for 4 h to passive vape (median PM2.5: 18 mu g/m(3) (range: 8-333)) and clean air (PM2.5 < 6 mu g/m(3)) separated by 14 days. Particles were measured using an ultrafine particle counter (P-TRAK) and a scanning mobility particle sizer (SMPS). Health effects including Surfactant Protein-A (SP-A) and albumin in exhaled air, spirometry, FeNO, and plasma proteins were evaluated before, right after, and 24 hours after exposure. Participants reported symptoms throughout exposure sessions. Data were analyzed using mixed models. Results: SP-A in exhaled air was negatively affected by exposure to vape and several plasma proteins increased significantly. Throat irritation was more pronounced during passive vape exposure, while FVC and FEV1 decreased, however, not significantly. Conclusions: SP-A in exhaled air and some plasma proteins were affected by passive vape in patients with COPD indicating inflammation, showing that passive vape exposure is potentially harmful.
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21.
  • Patterson, Allison, et al. (author)
  • Foraging range scales with colony size in high-latitude seabirds
  • 2022
  • In: Current Biology. - : Elsevier BV. - 0960-9822 .- 1879-0445. ; 32:17, s. 3800-3807
  • Journal article (peer-reviewed)abstract
    • Density-dependent prey depletion around breeding colonies has long been considered an important factor controlling the population dynamics of colonial animals.1, 2, 3, 4 Ashmole proposed that as seabird colony size increases, intraspecific competition leads to declines in reproductive success, as breeding adults must spend more time and energy to find prey farther from the colony.1 Seabird colony size often varies over several orders of magnitude within the same species and can include millions of individuals per colony.5,6 As such, colony size likely plays an important role in determining the individual behavior of its members and how the colony interacts with the surrounding environment.6 Using tracking data from murres (Uria spp.), the world’s most densely breeding seabirds, we show that the distribution of foraging-trip distances scales to colony size0.33 during the chick-rearing stage, consistent with Ashmole’s halo theory.1,2 This pattern occurred across colonies varying in size over three orders of magnitude and distributed throughout the North Atlantic region. The strong relationship between colony size and foraging range means that the foraging areas of some colonial species can be estimated from colony sizes, which is more practical to measure over a large geographic scale. Two-thirds of the North Atlantic murre population breed at the 16 largest colonies; by extrapolating the predicted foraging ranges to sites without tracking data, we show that only two of these large colonies have significant coverage as marine protected areas. Our results are an important example of how theoretical models, in this case, Ashmole’s version of central-place-foraging theory, can be applied to inform conservation and management in colonial breeding species.
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22.
  • Ritchie, C., et al. (author)
  • A systematic review shows minimal evidence for measurement properties of psychological functioning outcomes in whiplash
  • 2022
  • In: Journal of Clinical Epidemiology. - : Elsevier Inc.. - 0895-4356 .- 1878-5921. ; 151, s. 29-44
  • Journal article (peer-reviewed)abstract
    • Objectives: The aim of this study was to systematically identify, synthesize, and appraise studies on the measurement properties of patient-reported outcome measures (PROMs) for anxiety, depression, fear of movement, pain catastrophizing, post-traumatic stress, self-efficacy, and stress in people with whiplash-associated disorders (WAD). Study Design and Setting: PsycINFO, MEDLINE, EMBASE, CINAHL, PILOTS, Web of Science, and Scopus were searched (November 9, 2021). Studies evaluating any measurement property of relevant PROMs in WAD were included. Two reviewers independently screened the studies and assessed the measurement properties in accordance with the COSMIN guidelines. Results: Measurement properties of 10 PROMs were evaluated in WAD: Pictorial Fear of Activity Scale-Cervical (PFActS-C), Tampa Scale of Kinesiophobia-11, Pain Catastrophizing Scale (PCS), Pain Self-Efficacy Questionnaire (PSEQ), PSEQ-4 item, PSEQ-2a, PSEQ-2b, Self-Efficacy Scale, Harvard Trauma Questionnaire, and Post-Traumatic Stress Diagnostic Scale. Content validity was not examined in any of these PROMs in whiplash. Moderate- or high-quality evidence showed adequate internal structure for the PSEQ, PCS, and PFActS-C, whereas the original structures of the remaining seven PROMs were not confirmed in whiplash. Conclusion: Until further research on the measurement properties of these PROMs is available, researchers may opt to use the PSEQ, PCS, or PFActS-C if the construct is aligned with research aims. © 2022 Elsevier Inc.
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23.
  • Zanini, Luca, et al. (author)
  • Measurement of Volatile Radionuclides Production and Release Yields followed by a Post-Irradiation Analysis of a Pb/Bi Filled Ta Target at ISOLDE
  • 2014
  • In: Nuclear Data Sheets. - : Elsevier BV. - 0090-3752. ; 119, s. 292-295
  • Journal article (peer-reviewed)abstract
    • A crucial requirement in the development of liquid-metal spallation neutron target is knowledge of the composition and amount of volatile radionuclides that are released from the target during operation. It is also important to know the total amount produced, which could be released if there was an accident. One type is the lead-bismuth eutectic (LBE) target where different radionuclides can be produced following interaction with a high-energy proton beam, notably noble gases (Ar, Kr, Xe isotopes) and other relative volatile isotopes such as Hg and At. The results of an irradiation experiment performed at ISOLDE on a LBE target are compared with predictions from the MCNPX code using the latest developments on the Liege Intranuclear Cascade model (INCL4.6) and the CEM03 model. The calculations are able to reproduce the mass distribution of the radioisotopes produced, including the At production, where there is a significant contribution from secondary reactions. Subsequently, a post-irradiation examination of the irradiated target was performed. Investigations of both the tantalum target structure, in particular the beam window, and the lead-bismuth eutectic were performed using several experimental techniques. No sign of severe irradiation damage, previously observed in other ISOLDE targets, was found.
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24.
  • Acosta, Stefan, et al. (author)
  • Successful Selective Thrombolysis for Limb-Threatening Ischemia due to Bilateral Lower Extremity Emboli After Open Aortic Aneurysm Repair
  • 2010
  • In: Vascular and Endovascular Surgery. - : SAGE Publications. - 1938-9116 .- 1538-5744. ; 44:6, s. 506-507
  • Journal article (peer-reviewed)abstract
    • Severe lower extremity emboli with occlusion of all 3 lower limb arteries bilaterally occurred after an elective open abdominal aortic aneurysm (AAA) repair. Selective thrombolysis with alteplase and repeated percutaneous transluminal angioplasty (PTA) along the occlusions on both side anterior and posterior tibial arteries was performed without complications. Angiography the following day showed continuous filling of the anterior tibial artery down to the dorsalis pedis artery and interrupted, but improved, flow in the medial plantar artery through collaterals. The patient recovered well. At 1 month follow-up, the right foot was unremarkable, whereas the patient experienced slight residual numbness in the medial and distal plantar aspect of his left foot where the great toe/brachial index were lowered to 0.46.
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  • Result 1-25 of 62
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