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51.
  • Dreyling, Martin, et al. (författare)
  • Treatment for patients with relapsed/refractory mantle cell lymphoma : European-based recommendations
  • 2018
  • Ingår i: Leukemia and Lymphoma. - : Informa UK Limited. - 1042-8194 .- 1029-2403. ; 59:8, s. 1814-1828
  • Tidskriftsartikel (refereegranskat)abstract
    • Patients with mantle cell lymphoma (MCL) usually respond to initial combination chemotherapy, but the disease inevitably relapses and often follows an aggressive course. Here, clinical study results published since 2008 for patients with relapsed/refractory MCL were reviewed to compare available evidence for treatment guidance. Most trials identified were non-randomized, phase II studies performed at a limited number of sites, and many evaluated MCL as one of multiple non-Hodgkin lymphoma subtypes. Additional randomized, comparative trials are needed. Treatment selection generally depends on patient need, age and fitness, time of relapse, and line of therapy. Combination regimens typically produce higher response rates than single agents, and adding rituximab generally improves outcomes. The inclusion of ibrutinib, lenalidomide, temsirolimus, and bortezomib, represents an important advance for patients ineligible for, unable to tolerate, or failing high-intensity combination chemotherapy. A high need for effective treatments in relapsed/refractory MCL remains, particularly for elderly and frail patients.
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52.
  • Farinotti, Daniel, et al. (författare)
  • How accurate are estimates of glacier ice thickness? Results from ITMIX, the Ice Thickness Models Intercomparison eXperiment
  • 2017
  • Ingår i: The Cryosphere. - : Copernicus GmbH. - 1994-0416 .- 1994-0424. ; 11, s. 949-970
  • Tidskriftsartikel (refereegranskat)abstract
    • Knowledge of the ice thickness distribution of glaciers and ice caps is an important prerequisite for many glaciological and hydrological investigations. A wealth of approaches has recently been presented for inferring ice thickness from characteristics of the surface. With the Ice Thickness Models Intercomparison eXperiment (ITMIX) we performed the first coordinated assessment quantifying individual model performance. A set of 17 different models showed that individual ice thickness estimates can differ considerably – locally by a spread comparable to the observed thickness. Averaging the results of multiple models, however, significantly improved the results: on average over the 21 considered test cases, comparison against direct ice thickness measurements revealed deviations on the order of 10 ± 24 % of the mean ice thickness (1σ estimate). Models relying on multiple data sets – such as surface ice velocity fields, surface mass balance, or rates of ice thickness change – showed high sensitivity to input data quality. Together with the requirement of being able to handle large regions in an automated fashion, the capacity of better accounting for uncertainties in the input data will be a key for an improved next generation of ice thickness estimation approaches.
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53.
  • Follette, Katherine B., et al. (författare)
  • SEEDS ADAPTIVE OPTICS IMAGING OF THE ASYMMETRIC TRANSITION DISK OPH IRS 48 IN SCATTERED LIGHT
  • 2015
  • Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 798:2
  • Tidskriftsartikel (refereegranskat)abstract
    • We present the first resolved near-infrared imagery of the transition disk Oph IRS 48 (WLY 2-48), which was recently observed with ALMA to have a strongly asymmetric submillimeter flux distribution. H-band polarized intensity images show a similar to 60 AU radius scattered light cavity with two pronounced arcs of emission, one from northeast to southeast and one smaller, fainter, and more distant arc in the northwest. K-band scattered light imagery reveals a similar morphology, but with a clear third arc along the southwestern rim of the disk cavity. This arc meets the northwestern arc at nearly a right angle, revealing the presence of a spiral arm or local surface brightness deficit in the disk, and explaining the east-west brightness asymmetry in the H-band data. We also present 0.8-5.4 mu m IRTF SpeX spectra of this object, which allow us to constrain the spectral class to A0 +/- 1 and measure a low mass accretion rate of 10(-8.5) M-circle dot yr(-1), both consistent with previous estimates. We investigate a variety of reddening laws in order to fit the multiwavelength spectral energy distribution of Oph IRS 48 and find a best fit consistent with a younger, higher luminosity star than previous estimates.
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54.
  • Garcia, E. Victor, et al. (författare)
  • SCExAO AND GPI Y JH BAND PHOTOMETRY AND INTEGRAL FIELD SPECTROSCOPY OF THE YOUNG BROWN DWARF COMPANION TO HD 1160
  • 2017
  • Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 834:2
  • Tidskriftsartikel (refereegranskat)abstract
    • We present high signal-to-noise ratio, precise Y JH photometry and Y band (0.957-1.120 mu m) spectroscopy of HD 1160 B, a young substellar companion discovered from the Gemini NICI Planet Finding Campaign using the Subaru Coronagraphic Extreme Adaptive Optics instrument and the Gemini Planet Imager. HD 1160 B has typical mid-M dwarf-like infrared colors and a spectral type of M5.5(-0.5)(+1.0), where the blue edge of our Y band spectrum rules out earlier spectral types. Atmospheric modeling suggests HD 1160 B has an effective temperature of 3000-3100 K, a surface gravity of log g - 4-4.5, a radius of. 1.55 +/- 0.10 R-J, and a luminosity of log L/L circle dot - 2.76 +/- 0.05. Neither the primary's Hertzspring-Russell diagram position nor atmospheric modeling of HD 1160 B show evidence for a subsolar metallicity. Interpretation of the HD 1160 B spectroscopy depends on which stellar system components are used to estimate the age. Considering HD 1160 A, B and C jointly, we derive an age of 80-125 Myr, implying that HD 1160 B straddles the hydrogen-burning limit (70-90 M-J) If we consider HD 1160 A alone, younger ages (20-125 Myr) and a brown dwarf-like mass (35-90 M-J) are possible. Interferometric measurements of the primary, a precise Gaia parallax, and moderate-resolution spectroscopy can better constrain the system's age and how HD 1160 B fits within the context of (sub) stellar evolution.
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55.
  • Goosse, Hugues, et al. (författare)
  • Quantifying climate feedbacks in polar regions
  • 2018
  • Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 9
  • Tidskriftsartikel (refereegranskat)abstract
    • The concept of feedback is key in assessing whether a perturbation to a system is amplified or damped by mechanisms internal to the system. In polar regions, climate dynamics are controlled by both radiative and non-radiative interactions between the atmosphere, ocean, sea ice, ice sheets and land surfaces. Precisely quantifying polar feedbacks is required for a process-oriented evaluation of climate models, a clear understanding of the processes responsible for polar climate changes, and a reduction in uncertainty associated with model projections. This quantification can be performed using a simple and consistent approach that is valid for a wide range of feedbacks, offering the opportunity for more systematic feedback analyses and a better understanding of polar climate changes.
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56.
  • Gruyters, Pieter, et al. (författare)
  • Atomic diffusion and mixing in old stars VI. The lithium content of M30
  • 2016
  • Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 589
  • Tidskriftsartikel (refereegranskat)abstract
    • Context. The prediction of the Planck-constrained primordial lithium abundance in the Universe is in discordance with the observed Li abundances in warm Population II dwarf and subgiant stars. Among the physically best motivated ideas, it has been suggested that this discrepancy can be alleviated if the stars observed today had undergone photospheric depletion of lithium.Aims. The cause of this depletion is investigated by accurately tracing the behaviour of the lithium abundances as a function of effective temperature. Globular clusters are ideal laboratories for such an abundance analysis as the relative stellar parameters of their stars can be precisely determined.Methods. We performed a homogeneous chemical abundance analysis of 144 stars in the metal-poor globular cluster M30, ranging from the cluster turnoff point to the tip of the red giant branch. Non-local thermal equilibrium (NLTE) abundances for Li, Ca, and Fe were derived where possible by fitting spectra obtained with VLT/FLAMES-GIRAFFE using the quantitative-spectroscopy package SME. Stellar parameters were derived by matching isochrones to the observed V vs. V I colour-magnitude diagram. Independent effective temperatures were obtained from automated profile fitting of the Balmer lines and by applying colour-T-eff calibrations to the broadband photometry.Results. Li abundances of the turno ff and early subgiant stars form a thin plateau that is broken off abruptly in the middle of the SGB as a result of the onset of Li dilution caused by the first dredge-up. Abundance trends with effective temperature for Fe and Ca are observed and compared to predictions from stellar structure models including atomic diffusion and ad hoc additional mixing below the surface convection zone. The comparison shows that the stars in M30 are affected by atomic diffusion and additional mixing, but we were unable to determine the efficiency of the additional mixing precisely. This is the fourth globular cluster (after NGC6397, NGC6752, and M4) in which atomic diffusion signatures are detected. After applying a conservative correction (T6.0 model) for atomic diffusion, we find an initial Li abundance of A(Li) = 2.48 +/- 0.10 for the globular cluster M30. We also detected a Li-rich SGB star with a Li abundance of A(Li) = 2.39. The finding makes Li-rich mass transfer a likely scenario for this star and rules out models in which its Li enhancement is created during the RGB bump phase.
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57.
  • Guillén, Sergio, et al. (författare)
  • IoT European Large-Scale Pilots – Integration, Experimentation and Testing
  • 2017
  • Ingår i: Cognitive Hyperconnected Digital Transformation. - New York : Taylor & Francis. ; , s. 221-282
  • Bokkapitel (refereegranskat)abstract
    • The IoT European Large-Scale Pilots Programme includes the innovation consortia that are collaborating to foster the deployment of IoT solutions in Europe through the integration of advanced IoT technologies across the value chain, demonstration of multiple IoT applications at scale and in a usage context, and as close as possible to operational conditions.The programme projects are targeted, goal-driven initiatives that propose IoT approaches to specific real-life industrial/societal challenges. They are autonomous entities that involve stakeholders from the supply side to the demand side, and contain all the technological and innovation elements, the tasks related to the use, application and deployment as well as the development, testing and integration activities.This chapter describes the IoT Large Scale Pilot Programme initiative together with all involved actors. These actors include the coordination and support actions CREATE-IoT and U4IoT, being them drivers of the programme, and all five IoT Large-Scale Pilot projects, namely ACTIVAGE, IoF2020, MONICA, SynchroniCity and AUTOPILOT.ot projects, namely ACTIVAGE,IoF2020, MONICA, SynchroniCity and AUTOPILOT.
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58.
  • Gustafson, Johan, et al. (författare)
  • The Role of Oxides in Catalytic CO Oxidation over Rhodium and Palladium
  • 2018
  • Ingår i: ACS Catalysis. - : American Chemical Society (ACS). - 2155-5435. ; 8:5, s. 4438-4445
  • Tidskriftsartikel (refereegranskat)abstract
    • Catalytic CO oxidation is a seemingly simple reaction between CO and O2 molecules, one of the reactions in automotive catalytic converters, and the fruit-fly reaction in model catalysis. Surprisingly, the phase responsible for the catalytic activity is still under debate, despite decades of investigations. We have performed a simple but yet conclusive study of single crystal Rh and Pd model catalysts, resolving this controversy. For Rh, the oxygen-covered metallic surface is more active than the oxide, while for Pd, thin oxidefilms are at least as active as the metallic surface, but a thicker oxide is less active. Apart from resolving a long-standing debate, our results pinpoint important design principles for oxidation catalysts as to prevent catalytic extinction at high oxygen exposures.
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59.
  • Herman, Anne, et al. (författare)
  • Allergic contact dermatitis caused by isobornyl acrylate in Freestyle® Libre, a newly introduced glucose sensor
  • 2017
  • Ingår i: Contact Dermatitis. - : Wiley. - 0105-1873. ; 77:6, s. 367-373
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Glucose sensors, such as FreeStyle® Libre, are innovative medical devices developed for diabetes patients as a replacement for classic glucose meters, ensuring continuous glucose monitoring without the disadvantage of regular skin finger pricks. Objectives: To report several cases of allergic contact dermatitis caused by FreeStyle® Libre, and to report on isobornyl acrylate as a culprit allergen. Patients and Methods: Fifteen patients presented with allergic contact dermatitis caused by FreeStyle® Libre. All but 1 were patch tested with a baseline series, and with pieces and/or ultrasonic bath extracts of (the adhesive part of) the glucose sensor. Isobornyl acrylate was patch tested, in various concentrations and vehicles, in 13 patients. Gas chromatography–mass spectrometry (GC-MS) of the sensors was performed. Results: All patients reacted to the adhesive part of the sensor, and 12 patients were shown to be sensitized to isobornyl acrylate. Simultaneous reactions to other allergens were rarely observed. GC-MS showed the presence of isobornyl acrylate in the sensors. Conclusions: Cases of allergic contact dermatitis caused by FreeStyle® Libre are increasingly being observed, and isobornyl acrylate is a relevant culprit allergen. Cross-reactivity to other acrylates was infrequently observed, but other, hitherto unidentified, contact allergens may still be present in the device.
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60.
  • Herman, Anne, et al. (författare)
  • Unexpected positive patch test reactions to sesquiterpene lactones in patients sensitized to the glucose sensor FreeStyle Libre
  • 2019
  • Ingår i: Contact Dermatitis. - : Wiley. - 0105-1873 .- 1600-0536. ; 81:5, s. 354-367
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Most diabetic patients sensitized to FreeStyle Libre react to isobornyl acrylate (IBOA), with a considerable number of them also showing unexpected positive patch test reactions to sesquiterpene lactone (SL) mix (SLM) tested in the baseline series. Objectives: To compile patch test results of subjects affected, and provide potential explanations for this association. Patients and Methods: Fifty-three Freestyle Libre-allergic patients were patch tested with IBOA and/or SLM, and several were also patch tested with the components of SLM. Chromatographic analyses were performed on the glucose sensor, IBOA, and the components of SLM. Results: Thirty-three patients reacted positively to the components of SLM, and 11 of 27 patients reacted positively to alantolactone, in particular. Gas chromatography-mass spectrometry (GC-MS) analyses did not detect these chemicals in the different parts of the glucose sensor, or in IBOA. Conclusion: Significant co-sensitizations between SLs on the one hand and the glucose sensor FreeStyle Libre and/or isobornyl acrylate on the other hand exist, without evidence of the presence of SLs via GC-MS analysis. Cross-reactions between them seem improbable. As a possible hypothesis, a common precursor for both, such as camphene, may exist. Highlights: Of the diabetic patients sensitized to the glucose sensor FreeStyle Libre and/or IBOA, 62.3% reacted positively to SLM. Cross-reactions between IBOA and the three components of SLM (alantolactone, costunolide, and dehydrocostus lactone) seem unlikely, because of their different spatial structures. Co-sensitization between IBOA and SLS can be explained by the fact that there is a common precursor, such as camphene, between these two molecules.
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61.
  • Holl, M., et al. (författare)
  • Quasi-free neutron and proton knockout reactions from light nuclei in a wide neutron-to-proton asymmetry range
  • 2019
  • Ingår i: Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics. - : Elsevier BV. - 0370-2693. ; 795, s. 682-688
  • Tidskriftsartikel (refereegranskat)abstract
    • The quasi-free scattering reactions 11C(p,2p) and 10,11,12C(p,pn) have been studied in inverse kinematics at beam energies of 300–400 MeV/u at the R3B-LAND setup. The outgoing proton-proton and proton-neutron pairs were detected in coincidence with the reaction fragments in kinematically complete measurements. The efficiency to detect these pairs has been obtained from GEANT4 simulations which were tested using the 12C(p,2p) and 12C(p,pn) reactions. Experimental cross sections and momentum distributions have been obtained and compared to DWIA calculations based on eikonal theory. The new results reported here are combined with previously published cross sections for quasi-free scattering from oxygen and nitrogen isotopes and together they enable a systematic study of the reduction of single-particle strength compared to predictions of the shell model over a wide neutron-to-proton asymmetry range. The combined reduction factors show a weak or no dependence on isospin asymmetry, in contrast to the strong dependency reported in nucleon-removal reactions induced by nuclear targets at lower energies. However, the reduction factors for (p,2p) are found to be 'significantly smaller than for (p,pn) reactions for all investigated nuclei.
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62.
  • Höglin, Viktor, et al. (författare)
  • Sample cell for in-field X-ray diffraction experiments
  • 2015
  • Ingår i: Results in Physics. - : Elsevier BV. - 2211-3797. ; 5, s. 53-54
  • Tidskriftsartikel (refereegranskat)abstract
    • A sample cell making it possible to perform synchrotron radiation X-ray powder diffraction experiments in a magneticfield of 0.35 T has been constructed. The device is an add-on to an existing sample cell and contains a strong permanentmagnet of NdFeB-type. Experiments have shown that the setup is working satisfactory making it possible to performin-field measurements.
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63.
  • Johansson, Mattias, et al. (författare)
  • The influence of obesity-related factors in the etiology of renal cell carcinoma—A mendelian randomization study
  • 2019
  • Ingår i: PLoS Medicine. - : Public Library of Science (PLoS). - 1549-1277 .- 1549-1676. ; 16:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: Several obesity-related factors have been associated with renal cell carcinoma (RCC), but it is unclear which individual factors directly influence risk. We addressed this question using genetic markers as proxies for putative risk factors and evaluated their relation to RCC risk in a mendelian randomization (MR) framework. This methodology limits bias due to confounding and is not affected by reverse causation.Methods and findings: Genetic markers associated with obesity measures, blood pressure, lipids, type 2 diabetes, insulin, and glucose were initially identified as instrumental variables, and their association with RCC risk was subsequently evaluated in a genome-wide association study (GWAS) of 10,784 RCC patients and 20,406 control participants in a 2-sample MR framework. The effect on RCC risk was estimated by calculating odds ratios (ORSD) for a standard deviation (SD) increment in each risk factor. The MR analysis indicated that higher body mass index increases the risk of RCC (ORSD: 1.56, 95% confidence interval [CI] 1.44–1.70), with comparable results for waist-to-hip ratio (ORSD: 1.63, 95% CI 1.40–1.90) and body fat percentage (ORSD: 1.66, 95% CI 1.44–1.90). This analysis further indicated that higher fasting insulin (ORSD: 1.82, 95% CI 1.30–2.55) and diastolic blood pressure (DBP; ORSD: 1.28, 95% CI 1.11–1.47), but not systolic blood pressure (ORSD: 0.98, 95% CI 0.84–1.14), increase the risk for RCC. No association with RCC risk was seen for lipids, overall type 2 diabetes, or fasting glucose.Conclusions: This study provides novel evidence for an etiological role of insulin in RCC, as well as confirmatory evidence that obesity and DBP influence RCC risk.
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64.
  • Konishi, Mihoko, et al. (författare)
  • A substellar companion to Pleiades HII 3441
  • 2016
  • Ingår i: Publications of the Astronomical Society of Japan. - : Oxford University Press (OUP). - 0004-6264 .- 2053-051X. ; 68:6
  • Tidskriftsartikel (refereegranskat)abstract
    • We find a new substellar companion to the Pleiades member star, Pleiades HII 3441, using the Subaru telescope with adaptive optics. The discovery is made as part of the high-contrast imaging survey to search for planetary-mass and substellar companions in the Pleiades and young moving groups. The companion has a projected separation of 0.'' 49 +/- 0.'' 02 (66 +/- 2 au) and a mass of 68 +/- 5 M-J based on three observations in the J-, H-, and K-s-bands. The spectral type is estimated to be M7 (similar to 2700 K), and thus no methane absorption is detected in the H band. Our Pleiades observations result in the detection of two substellar companions including one previously reported among 20 observed Pleiades stars, and indicate that the fraction of substellar companions in the Pleiades is about 10.0(-8.8)(+26.1)%. This is consistent with multiplicity studies of both the Pleiades stars and other open clusters.
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65.
  • Kooistra, Robin, et al. (författare)
  • Radial decoupling of small and large dust grains in the transitional disk RX J1615.3-3255
  • 2017
  • Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 597
  • Tidskriftsartikel (refereegranskat)abstract
    • We present H-band (1.6 mu m) scattered light observations of the transitional disk RX J1615.3-3255, located in the similar to 1 Myr old Lupus association. From a polarized intensity image, taken with the HiCIAO instrument of the Subaru Telescope, we deduce the position angle and the inclination angle of the disk. The disk is found to extend out to 68 +/- 12 AU in scattered light and no clear structure is observed. Our inner working angle of 24 AU does not allow us to detect a central decrease in intensity similar to that seen at 30 AU in the 880 mu m continuum observations. We compare the observations with multiple disk models based on the spectral energy distribution (SED) and submm interferometry and find that an inner rim of the outer disk at 30 AU containing small silicate grains produces a polarized intensity signal which is an order of magnitude larger than observed. We show that a model in which the small dust grains extend smoothly into the cavity found for large grains is closer to the actual H-band observations. A comparison of models with di ff erent dust size distributions suggests that the dust in the disk might have undergone significant processing compared to the interstellar medium.
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66.
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67.
  • Lanza, Nina L., et al. (författare)
  • Oxidation of manganese in an ancient aquifer, Kimberley formation, Gale crater, Mars
  • 2016
  • Ingår i: Geophysical Research Letters. - 0094-8276 .- 1944-8007. ; 43:14, s. 7398-7407
  • Tidskriftsartikel (refereegranskat)abstract
    • The Curiosity rover observed high Mn abundances (>25wt % MnO) in fracture-filling materials that crosscut sandstones in the Kimberley region of Gale crater, Mars. The correlation between Mn and trace metal abundances plus the lack of correlation between Mn and elements such as S, Cl, and C, reveals that these deposits are Mn oxides rather than evaporites or other salts. On Earth, environments that concentrate Mn and deposit Mn minerals require water and highly oxidizing conditions; hence, these findings suggest that similar processes occurred on Mars. Based on the strong association between Mn-oxide deposition and evolving atmospheric dioxygen levels on Earth, the presence of these Mn phases on Mars suggests that there was more abundant molecular oxygen within the atmosphere and some groundwaters of ancient Mars than in the present day
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68.
  • Lomax, Jamie R., et al. (författare)
  • CONSTRAINING THE MOVEMENT OF THE SPIRAL FEATURES AND THE LOCATIONS OF PLANETARY BODIES WITHIN THE AB AUR SYSTEM
  • 2016
  • Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 828:1
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a new analysis of multi-epoch, H-band, scattered light images of the AB Aur system. We use a Monte Carlo radiative transfer code to simultaneously model the system's spectral energy distribution (SED) and H-band polarized intensity (PI) imagery. We find that a disk-dominated model, as opposed to one that is envelope-dominated, can plausibly reproduce AB Aur's SED and near-IR imagery. This is consistent with previous modeling attempts presented in the literature and supports the idea that at least a subset of AB Aur's spirals originate within the disk. In light of this, we also analyzed the movement of spiral structures in multi-epoch H-band total light and PI imagery of the disk. We detect no significant rotation or change in spatial location of the spiral structures in these data, which span a 5.8-year baseline. If such structures are caused by disk-planet interactions, the lack of observed rotation constrains the location of the orbit of planetary perturbers to be >47 au.
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69.
  • Lundgren, Camilla A. K, et al. (författare)
  • Scavenging of superoxide by a membrane-bound superoxide oxidase
  • 2018
  • Ingår i: Nature Chemical Biology. - : Springer Science and Business Media LLC. - 1552-4450 .- 1552-4469. ; 14, s. 788-793
  • Tidskriftsartikel (refereegranskat)abstract
    • Superoxide is a reactive oxygen species produced during aerobic metabolism in mitochondria and prokaryotes. It causes damage to lipids, proteins and DNA and is implicated in cancer, cardiovascular disease, neurodegenerative disorders and aging. As protection, cells express soluble superoxide dismutases, disproportionating superoxide to oxygen and hydrogen peroxide. Here, we describe a membrane-bound enzyme that directly oxidizes superoxide and funnels the sequestered electrons to ubiquinone in a diffusion-limited reaction. Experiments in proteoliposomes and inverted membranes show that the protein is capable of efficiently quenching superoxide generated at the membrane in vitro. The 2.0 Å crystal structure shows an integral membrane di-heme cytochrome b poised for electron transfer from the P-side and proton uptake from the N-side. This suggests that the reaction is electrogenic and contributes to the membrane potential while also conserving energy by reducing the quinone pool. Based on this enzymatic activity, we propose that the enzyme family be denoted superoxide oxidase (SOO).
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70.
  • Martin, Natalia Mihaela, 1984, et al. (författare)
  • A LEIS and in situ XAS study of supported Pd-Pt catalysts for CH4 oxidation
  • 2016
  • Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
    • It is of vital importance to remove methane (CH4) from the exhausts of natural gas and biogas fueled engines as CH4 is a strong greenhouse gas. So far Pd-based catalysts have been used almost exclusively but their high sensitivity to sulfur and water pushes research to explore other materials. Among these are Pd-Pt catalysts [1-4], which exhibit a slight increase in CH4 oxidation activity with time and higher long-term stability than the Pd-only counterpart [5-7]. Still, however, little is known about the oxidation-reduction behaviour of the Pd-Pt nanoclusters and how this impacts the catalytic activity. This study aims at increase the understanding of the catalytic activity of Al2O3-supported Pd-Pt nanoclusters for low-temperature CH4 oxidation under transient, although generally lean, conditions.
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71.
  • Martin, Natalia M., et al. (författare)
  • CO Oxidation and Site Speciation for Alloyed Palladium-Platinum Model Catalysts Studied by in Situ FTIR Spectroscopy
  • 2017
  • Ingår i: Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 121:47, s. 26321-26329
  • Tidskriftsartikel (refereegranskat)abstract
    • In situ Fourier transform infrared spectroscopy was used to study transient CO oxidation over a series of bimetallic Pd-Pt catalysts with different Pd:Pt molar ratios. The catalysts were found to contain both alloyed PdPt nanoparticles (particle sizes 25-35 nm) and monometallic Pd nanoparticles (sizes below 10 nm). For oxygen-free conditions, CO reduces the surface while simultaneously function as a chemical probe molecule whereby the CO adsorption sites can be characterized. Under these conditions, it is shown that adsorbed carbonyl species form both on the Pd and Pt. On platinum, CO adsorbs predominantly linearly on top, whereas on palladium it adsorbes in bridged configurations. This behavior is used for site speciation of the catalysts. The spectra from the bimetallic Pd-Pt catalysts are more complicated than a direct superposition of the spectra for the monometallic catalysts as a consequence of alloy formation and enrichment of Pd at the surface of the reduced catalysts. The temperature-programmed CO oxidation results show that the addition of Pd to the Pt catalyst supported on alumina shifts the CO-poisoned state to lower temperatures, therefore increasing the temperature range for the CO oxidation at low temperatures.
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72.
  • Martin, Natalia Mihaela, 1984, et al. (författare)
  • CO Oxidation and Site Speciation for Alloyed Pd-Pt Model Catalysts Studied by In Situ FTIR Spectroscopy
  • 2017
  • Ingår i: Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 121:47, s. 26321-26329
  • Tidskriftsartikel (refereegranskat)abstract
    • In situ Fourier transform infrared spectroscopy was used to study transient CO oxidation over a series of bimetallic Pd-Pt catalysts with different Pd:Pt molar ratios. The catalysts were found to contain both alloyed PdPt nanoparticles (particle sizes 25-35 nm) and monometallic Pd nanoparticles (sizes below 10 nm). For oxygen-free conditions, CO reduces the surface while simultaneously function as a chemical probe molecule whereby the CO adsorption sites can be characterised. Under these conditions it is shown that adsorbed carbonyl species form both on the Pd and Pt. On platinum, CO adsorbs predominantly linearly on top, whereas on palladium it adsorbes in bridged configurations. This behaviour is used for site speciation of the catalysts. The spectra from the bimetallic Pd-Pt catalysts are more complicated than a direct superposition of the spectra for the monometallic catalysts as a consequence of alloy formation and enrichment of Pd at the surface of the reduced catalysts. The temperature programmed CO oxidation results show that the addition of Pd to the Pt catalyst supported on alumina shifts the CO-poisoned state to lower temperatures therefore increasing the temperature range for the CO oxidation at low temperatures.
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73.
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74.
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75.
  • McKibbin, Sarah R., et al. (författare)
  • In situ observation of synthesized nanoparticles in ultra-dilute aerosols via X-ray scattering
  • 2019
  • Ingår i: Nano Research. - : Springer Science and Business Media LLC. - 1998-0124 .- 1998-0000. ; 12:1, s. 25-31
  • Tidskriftsartikel (refereegranskat)abstract
    • In-air epitaxy of nanostructures (Aerotaxy) has recently emerged as a viable route for fast, large-scale production. In this study, we use small-angle X-ray scattering to perform direct in-flight characterizations of the first step of this process, i.e., the engineered formation of Au and Pt aerosol nanoparticles by spark generation in a flow of N2 gas. This represents a particular challenge for characterization because the particle density can be extremely low in controlled production. The particles produced are examined during production at operational pressures close to atmospheric conditions and exhibit a lognormal size distribution ranging from 5–100 nm. The Au and Pt particle production and detection are compared. We observe and characterize the nanoparticles at different stages of synthesis and extract the corresponding dominant physical properties, including the average particle diameter and sphericity, as influenced by particle sintering and the presence of aggregates. We observe highly sorted and sintered spherical Au nanoparticles at ultra-dilute concentrations (< 5 × 105 particles/cm3) corresponding to a volume fraction below 3 × 10–10, which is orders of magnitude below that of previously measured aerosols. We independently confirm an average particle radius of 25 nm via Guinier and Kratky plot analysis. Our study indicates that with high-intensity synchrotron beams and careful consideration of background removal, size and shape information can be obtained for extremely low particle concentrations with industrially relevant narrow size distributions. [Figure not available: see fulltext.].
  •  
76.
  • Mitkus, Mindaugas, et al. (författare)
  • Raptor vision
  • 2018
  • Ingår i: Oxford Research Encyclopedia of Neuroscience. - : Oxford University Press. - 9780190264086
  • Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
    • Diurnal raptors (birds of the orders Accipitriformes and Falconiformes), renowned for their extraordinarily sharp eyesight, have fascinated humans for centuries. The high visual acuity in some raptor species is possible due to their large eyes, both in relative and absolute terms, and a high density of cone photoreceptors. Some large raptors, such as wedge-tailed eagles and the Old World vultures, have visual acuities twice as high as humans and six times as high as ostriches—the animals with the largest terrestrial eyes. The raptor retina has rods, double cones, and four spectral types of single cones. The highest density of single cones occurs in one or two specialized retinal regions: the foveae, where, at least in some species, rods and double cones are absent. The deep central fovea allows for the highest acuity in the lateral visual field that is probably used for detecting prey from a large distance. Pursuit-hunting raptors have a second, shallower, temporal fovea that allows for sharp vision in the frontal field of view. Scavenging carrion eaters do not possess a temporal fovea that may indicate different needs in foraging behavior. Moreover, pursuit-hunting and scavenging raptors also differ in configuration of visual fields, with a more extensive field of view in scavengers.The eyes of diurnal raptors, unlike those of most other birds, are not very sensitive to ultraviolet light, which is strongly absorbed by their cornea and lens. As a result of the low density of rods, and the narrow and densely packed single cones in the central fovea, the visual performance of diurnal raptors drops dramatically as light levels decrease. These and other visual properties underpin prey detection and pursuit and show how these birds’ vision is adapted to make them successful diurnal predators.
  •  
77.
  • Momose, Munetake, et al. (författare)
  • Detailed structure of the outer disk around HD169142 with polarized light in H-band
  • 2015
  • Ingår i: Nippon Tenmon Gakkai obun kenkyu hokoku. - : Oxford University Press (OUP). - 0004-6264. ; 67:5
  • Tidskriftsartikel (refereegranskat)abstract
    • Coronagraphic imagery of the circumstellar disk around HD 169142 in H-band polarized intensity (PI) with Subaru/HiCIAO is presented. The emission scattered by dust particles at the disk surface in 0.2 <= r <= 1.2, or 29 <= r <= 174 AU, is successfully detected. The azimuthally-averaged radial profile of the PI shows a double power-law distribution, in which the PIs in r=29-52 AU and r=81.2-145 AU respectively show r(-3)-dependence. These two power-law regions are connected smoothly with a transition zone (TZ), exhibiting an apparent gap in r=40-70 AU. The PI in the inner power-law region shows a deep minimum whose location seems to coincide with the point source at lambda = 7 mm. This can be regarded as another sign of a protoplanet in TZ. The observed radial profile of the PI is reproduced by a minimally flaring disk with an irregular surface density distribution or with an irregular temperature distribution or with the combination of both. The depletion factor of surface density in the inner power-law region (r<50 AU) is derived to be >= 0.16 from a simple model calculation. The obtained PI image also shows small scale asymmetries in the outer power-law region. Possible origins for these asymmetries include corrugation of the scattering surface in the outer region, and shadowing effect by a puffed up structure in the inner power-law region.
  •  
78.
  • Morris, Simon, et al. (författare)
  • The ELT-MOS (MOSAIC) : towards the construction phase
  • 2018
  • Ingår i: GROUND-BASED AND AIRBORNE INSTRUMENTATION FOR ASTRONOMY VII. - : SPIE-INT SOC OPTICAL ENGINEERING. - 9781510619586 ; 10702
  • Konferensbidrag (refereegranskat)abstract
    • When combined with the huge collecting area of the ELT, MOSAIC will be the most effective and flexible Multi-Object Spectrograph (MOS) facility in the world, having both a high multiplex and a multi-Integral Field Unit (Multi-IFU) capability. It will be the fastest way to spectroscopically follow-up the faintest sources, probing the reionisation epoch, as well as evaluating the evolution of the dwarf mass function over most of the age of the Universe. MOSAIC will be world-leading in generating an inventory of both the dark matter (from realistic rotation curves with MOAO fed NIR IFUs) and the cool to warm-hot gas phases in z=3.5 galactic haloes (with visible wavelenth IFUs). Galactic archaeology and the first massive black holes are additional targets for which MOSAIC will also be revolutionary. MOAO and accurate sky subtraction with fibres have now been demonstrated on sky, removing all low Technical Readiness Level (TRL) items from the instrument. A prompt implementation of MOSAIC is feasible, and indeed could increase the robustness and reduce risk on the ELT, since it does not require diffraction limited adaptive optics performance. Science programmes and survey strategies are currently being investigated by the Consortium, which is also hoping to welcome a few new partners in the next two years.
  •  
79.
  • Nedumkandathil, Reji, et al. (författare)
  • Hydrogenation induced structure and property changes in GdGa
  • 2016
  • Ingår i: Journal of Solid State Chemistry. - : Elsevier BV. - 0022-4596 .- 1095-726X. ; 239, s. 184-191
  • Tidskriftsartikel (refereegranskat)abstract
    • Hydrides GdGaH were obtained by exposing the Zintl phase GdGa with the CrB structure to a hydrogen atmosphere at pressures from 1.5 to 50 bar and temperatures from 50 to 500 degrees C. Structural analysis by powder X-ray diffraction suggests that conditions with hydrogen pressures in a range between 15 and 50 bar and temperatures below 500 degrees C afford a uniform hydride phase with the NdGaH1.66 structure (Cmcm, a=3.9867(7) angstrom, b=12.024(2) angstrom, c=4.1009(6) angstrom) which hosts H in two distinct positions, H1 and H2. H1 is coordinated in a tetrahedral fashion by Gd atoms, whereas H2 atoms are inserted between Ga atoms. The assignment of the NdGaH1.66 structure is corroborated by first principles DFT calculations. Modeling of phase and structure stability as a function of composition resulted in excellent agreement with experimental lattice parameters when x=1.66 and revealed the presence of five-atom moieties Ga-H2-Ga-H2-Ga in GdGaH1.66. From in situ powder X-ray diffraction using synchrotron radiation it was established that hydrogenation at temperatures above 200 degrees C affords a hydride with x approximate to 1.3, which is stable up to 500 degrees C, and that additional H absorption, yielding GdGaH1.66, takes place at lower temperatures. Consequently, GdGaH1.66 desorbs H above T=200 degrees C. Without the presence of hydrogen, hydrides GdGaHx decompose at temperatures above 300 degrees C into GdH2 and an unidentified Gd-Ga intermetallics. Thus the hydrogenation of GdGa is not reversible. From magnetic measurements the Curie Weiss constant and effective magnetic moment of GdGaH1.66 were obtained. The former indicates antiferromagnetic interactions, the latter attains a value of similar to 8 mu B which is typical for compounds containing Gd3+ ions.
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80.
  • Nowosielski, Martha, et al. (författare)
  • Radiologic progression of glioblastoma under therapy : an exploratory analysis of AVAglio
  • 2018
  • Ingår i: Neuro-Oncology. - : Oxford University Press. - 1522-8517 .- 1523-5866. ; 20:4, s. 557-566
  • Tidskriftsartikel (refereegranskat)abstract
    • In this exploratory analysis of AVAglio, a randomized phase III clinical study that investigated the addition of bevacizumab (Bev) to radiotherapy/temozolomide in newly diagnosed glioblastoma, we aim to radiologically characterize glioblastoma on therapy until progression and investigate whether the type of radiologic progression differs between treatment arms and is related to survival and molecular data. Five progression types (PTs) were categorized using an adapted algorithm according to MRI contrast enhancement behavior in T1- and T2-weighted images in 621 patients (Bev, n = 299; placebo, n = 322). Frequencies of PTs (designated as classic T1, cT1 relapse, T2 diffuse, T2 circumscribed, and primary nonresponder), time to progression (PFS), and overall survival (OS) were assessed within each treatment arm and compared with molecular subtypes and O-6-methylguanine DNA methyltransferase (MGMT) promoter methylation status. PT frequencies differed between the Bev and placebo arms, except for "T2 diffuse" (12.4% and 7.1%, respectively). PTs showed differences in PFS and OS; with "T2 diffuse" being associated with longest survival. Complete disappearance of contrast enhancement during treatment ("cT1 relapse") showed longer survival than only partial contrast enhancement decrease ("classic T1"). "T2 diffuse" was more commonly MGMT hypermethylated. Only weak correlations to molecular subtypes from primary tissue were detected. Progression of glioblastoma under therapy can be characterized radiologically. These radiologic phenotypes are influenced by treatment and develop differently over time with differential outcomes. Complete resolution of contrast enhancement during treatment is a favorable factor for outcome.
  •  
81.
  • ODonnell, Michael, et al. (författare)
  • Registered Replication Report: Dijksterhuis and van Knippenberg (1998)
  • 2018
  • Ingår i: Perspectives on Psychological Science. - : SAGE PUBLICATIONS LTD. - 1745-6916 .- 1745-6924. ; 13:2, s. 268-294
  • Tidskriftsartikel (refereegranskat)abstract
    • Dijksterhuis and van Knippenberg (1998) reported that participants primed with a category associated with intelligence (professor) subsequently performed 13% better on a trivia test than participants primed with a category associated with a lack of intelligence (soccer hooligans). In two unpublished replications of this study designed to verify the appropriate testing procedures, Dijksterhuis, van Knippenberg, and Holland observed a smaller difference between conditions (2%-3%) as well as a gender difference: Men showed the effect (9.3% and 7.6%), but women did not (0.3% and -0.3%). The procedure used in those replications served as the basis for this multilab Registered Replication Report. A total of 40 laboratories collected data for this project, and 23 of these laboratories met all inclusion criteria. Here we report the meta-analytic results for those 23 direct replications (total N = 4,493), which tested whether performance on a 30-item general-knowledge trivia task differed between these two priming conditions (results of supplementary analyses of the data from all 40 labs, N = 6,454, are also reported). We observed no overall difference in trivia performance between participants primed with the professor category and those primed with the hooligan category (0.14%) and no moderation by gender.
  •  
82.
  • Oh, Daehyeon, et al. (författare)
  • A RESOLVED NEAR-INFRARED IMAGE OF THE INNER CAVITY IN THE GM Aur TRANSITIONAL DISK
  • 2016
  • Ingår i: Astrophysical Journal Letters. - 2041-8205 .- 2041-8213. ; 831:1
  • Tidskriftsartikel (refereegranskat)abstract
    • We present high-contrast H-band polarized intensity (PI) images of the transitional disk around the young solar-like star GM Aur. The near-infrared direct imaging of the disk was derived by polarimetric differential imaging using the Subaru 8.2 m Telescope and HiCIAO. An angular resolution and an inner working angle of 0 ''.07 and r similar to 0 ''.05, respectively, were obtained. We clearly resolved a large inner cavity, with a measured radius of 18 +/- 2 au, which is smaller than that of a submillimeter interferometric image (28 au). This discrepancy in the cavity radii at near-infrared and submillimeter wavelengths may be caused by a 3-4M(Jup) planet about 20 au away from the star, near the edge of the cavity. The presence of a near-infrared inner cavity is a strong constraint on hypotheses for inner cavity formation in a transitional disk. A dust filtration mechanism has been proposed to explain the large cavity in the submillimeter image, but our results suggest that this mechanism must be combined with an additional process. We found that the PI slope of the outer disk is significantly different from the intensity slope obtained from HST/NICMOS, and this difference may indicate the grain growth process in the disk.
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83.
  • Ohta, Yurina, et al. (författare)
  • Extreme asymmetry in the polarized disk of V1247 Orionis
  • 2016
  • Ingår i: Nippon Tenmon Gakkai obun kenkyu hokoku. - : Oxford University Press (OUP). - 0004-6264. ; 68:4
  • Tidskriftsartikel (refereegranskat)abstract
    • We present the first near-infrared scattered-light detection of the transitional disk around V1247 Ori, which was obtained using high-resolution polarimetric differential imaging observations with Subaru/HiCIAO. Our imaging in the H band reveals the disk morphology at separations of similar to 0.'' 14-0.'' 86 (54-330 au) from the central star. The polarized intensity image shows a remarkable arc-like structure toward the southeast of the star, whereas the fainter northwest region does not exhibit any notable features. The shape of the arm is consistent with an arc of 0.'' 28 +/- 0.'' 09 in radius (108 au from the star), although the possibility of a spiral arm with a small pitch angle cannot be excluded. V1247 Ori features an exceptionally large azimuthal contrast in scattered, polarized light; the radial peak of the southeastern arc is about three times brighter than the northwestern disk measured at the same distance from the star. Combined with the previous indication of an inhomogeneous density distribution in the gap at less than or similar to 46 au, the notable asymmetry in the outer disk suggests the presence of unseen companions and/or planet-forming processes ongoing in the arc.
  •  
84.
  • Pandolfi, Marco, et al. (författare)
  • A European aerosol phenomenology-6 : scattering properties of atmospheric aerosol particles from 28 ACTRIS sites
  • 2018
  • Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 18:11, s. 7877-7911
  • Tidskriftsartikel (refereegranskat)abstract
    • This paper presents the light-scattering properties of atmospheric aerosol particles measured over the past decade at 28 ACTRIS observatories, which are located mainly in Europe. The data include particle light scattering (sigma(sp)) and hemispheric backscattering (sigma(bsp)) coefficients, scattering Angstrom exponent (SAE), backscatter fraction (BF) and asymmetry parameter (g). An increasing gradient of sigma(sp) is observed when moving from remote environments (arctic/mountain) to regional and to urban environments. At a regional level in Europe, sigma(sp) also increases when moving from Nordic and Baltic countries and from western Europe to central/eastern Europe, whereas no clear spatial gradient is observed for other station environments. The SAE does not show a clear gradient as a function of the placement of the station. However, a west-to-east-increasing gradient is observed for both regional and mountain placements, suggesting a lower fraction of fine-mode particle in western/south-western Europe compared to central and eastern Europe, where the fine-mode particles dominate the scattering. The g does not show any clear gradient by station placement or geographical location reflecting the complex relationship of this parameter with the physical properties of the aerosol particles. Both the station placement and the geographical location are important factors affecting the intraannual variability. At mountain sites, higher sigma(sp) and SAE values are measured in the summer due to the enhanced boundary layer influence and/or new particle-formation episodes. Conversely, the lower horizontal and vertical dispersion during winter leads to higher sigma(sp) values at all low-altitude sites in central and eastern Europe compared to summer. These sites also show SAE maxima in the summer (with corresponding g minima). At all sites, both SAE and g show a strong variation with aerosol particle loading. The lowest values of g are always observed together with low sigma(sp) values, indicating a larger contribution from particles in the smaller accumulation mode. During periods of high sigma(sp) values, the variation of g is less pronounced, whereas the SAE increases or decreases, suggesting changes mostly in the coarse aerosol particle mode rather than in the fine mode. Statistically significant decreasing trends of sigma(sp) are observed at 5 out of the 13 stations included in the trend analyses. The total reductions of sigma(sp) are consistent with those reported for PM2.5 and PM10 mass concentrations over similar periods across Europe.
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85.
  • Pfeifer, Marion, et al. (författare)
  • Tropical forest canopies and their relationships with climate and disturbance : results from a global dataset of consistent field-based measurements
  • 2018
  • Ingår i: Forest Ecosystems. - : Elsevier BV. - 2095-6355 .- 2197-5620. ; 5:7
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundCanopy structure, defined by leaf area index (LAI), fractional vegetation cover (FCover) and fraction of absorbed photosynthetically active radiation (fAPAR), regulates a wide range of forest functions and ecosystem services. Spatially consistent field-measurements of canopy structure are however lacking, particularly for the tropics.MethodsHere, we introduce the Global LAI database: a global dataset of field-based canopy structure measurements spanning tropical forests in four continents (Africa, Asia, Australia and the Americas). We use these measurements to test for climate dependencies within and across continents, and to test for the potential of anthropogenic disturbance and forest protection to modulate those dependences.ResultsUsing data collected from 887 tropical forest plots, we show that maximum water deficit, defined across the most arid months of the year, is an important predictor of canopy structure, with all three canopy attributes declining significantly with increasing water deficit. Canopy attributes also increase with minimum temperature, and with the protection of forests according to both active (within protected areas) and passive measures (through topography). Once protection and continent effects are accounted for, other anthropogenic measures (e.g. human population) do not improve the model.ConclusionsWe conclude that canopy structure in the tropics is primarily a consequence of forest adaptation to the maximum water deficits historically experienced within a given region. Climate change, and in particular changes in drought regimes may thus affect forest structure and function, but forest protection may offer some resilience against this effect.
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86.
  • Planque, Benjamin, et al. (författare)
  • A participatory scenario method to explore the future of marine social-ecological systems
  • 2019
  • Ingår i: Fish and Fisheries. - : Wiley. - 1467-2960 .- 1467-2979. ; 20:3, s. 434-451
  • Tidskriftsartikel (refereegranskat)abstract
    • Anticipating future changes in marine social-ecological systems (MSES) several decades into the future is essential in the context of accelerating global change. This is challenging in situations where actors do not share common understandings, practices, or visions about the future. We introduce a dedicated scenario method for the development of MSES scenarios in a participatory context. The objective is to allow different actors to jointly develop scenarios which contain their multiple visions of the future. The method starts from four perspectives: fisheries management, ecosystem, ocean climate, and global context and governance for which current status and recent trends are summarized. Contrasted scenarios about possible futures are elaborated for each of the four single perspectives before being integrated into multiple-perspective scenarios. Selected scenarios are then developed into storylines. Focusing on individual perspectives until near the end allows actors with diverse cultures, interests and horizons to confront their own notions of the future. We illustrate the method with the exploration of the futures of the Barents Sea MSES by 2050. We emphasize the following lessons learned: first, many actors are not familiar with scenario building and attention must be paid to explaining the purpose, methodology, and benefits of scenarios exercises. Second, although the Barents Sea MSES is relatively well understood, uncertainties about its future are significant. Third, it is important to focus on unlikely events. Fourth, all perspectives should be treated equally. Fifth, as MSES are continuously changing, we can only be prepared for future changes if we collectively keep preparing.
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87.
  • Potier, Simon, et al. (författare)
  • Visual abilities in two raptors with different ecology
  • 2016
  • Ingår i: Journal of Experimental Biology. - : The Company of Biologists. - 0022-0949 .- 1477-9145. ; 219:17, s. 2639-2649
  • Tidskriftsartikel (refereegranskat)abstract
    • Differences in visual capabilities are known to reflect differences in foraging behaviour even among closely related species. Among birds, the foraging of diurnal raptors is assumed to be guided mainly by vision but their foraging tactics include both scavenging upon immobile prey and the aerial pursuit of highly mobile prey. We studied how visual capabilities differ between two diurnal raptor species of similar size: Harris's hawks, Parabuteo unicinctus, which take mobile prey, and black kites, Milvus migrans, which are primarily carrion eaters. We measured visual acuity, foveal characteristics and visual fields in both species. Visual acuity was determined using a behavioural training technique; foveal characteristics were determined using ultra-high resolution spectraldomain optical coherence tomography (OCT); and visual field parameters were determined using an ophthalmoscopic reflex technique. We found that these two raptors differ in their visual capacities. Harris's hawks have a visual acuity slightly higher than that of black kites. Among the five Harris's hawks tested, individuals with higher estimated visual acuity made more horizontal head movements before making a decision. This may reflect an increase in the use of monocular vision. Harris's hawks have two foveas (one central and one temporal), while black kites have only one central fovea and a temporal area. Black kites have a wider visual field than Harris's hawks. This may facilitate the detection of conspecifics when they are scavenging. These differences in the visual capabilities of these two raptors may reflect differences in the perceptual demands of their foraging behaviours.
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88.
  • Raison-Peyron, Nadia, et al. (författare)
  • Allergic contact dermatitis caused by isobornyl acrylate in OmniPod, an innovative tubeless insulin pump
  • 2018
  • Ingår i: Contact Dermatitis. - : Wiley. - 0105-1873. ; 79:2, s. 76-80
  • Tidskriftsartikel (refereegranskat)abstract
    • Background: The frequency of allergic contact dermatitis caused by (meth)acrylates is increasing worldwide, and isobornyl acrylate (IBOA) has been identified as a culprit sensitizer in FreeStyle Libre, a medical device used by diabetic patients. Objectives: To report on 4 patients sensitized to IBOA contained in OmniPod, a new, tubeless insulin pump, and to describe the clinical and chemical analytical work-up. Method: Four patients with eczematous skin eruptions after using OmniPod, including 2 with previous adverse skin reactions to FreeStyle Libre, were patch tested with a baseline series and additional (meth)acrylates, including IBOA in several concentrations and/or vehicles. Gas chromatography-mass spectrometry (GC-MS) was used to identify the presence of IBOA in OmniPod. Results: All patients were shown to be sensitized to IBOA. GC-MS identified IBOA in OmniPod, with the highest concentrations being found in the unit itself and not in the adhesive patch. Conclusions: The OmniPod tubeless insulin pump is another source of IBOA, and its use may lead to primary sensitization to this acrylate, or may provoke elicitation of allergic contact dermatitis in previously sensitized patients. Our cases highlight the need to obtain satisfactory cooperation from pharmaceutical companies involved in the manufacture of these widely used medical devices.
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89.
  • Ramasamy, Madhumidha, et al. (författare)
  • Influence of Microstructure and Surface Activation of Dual-Phase Membrane Ce0.8Gd0.2O2−δ–FeCo2O4 on Oxygen Permeation
  • 2016
  • Ingår i: Journal of The American Ceramic Society. - : Wiley. - 0002-7820 .- 1551-2916. ; 99:1, s. 349-355
  • Tidskriftsartikel (refereegranskat)abstract
    • Dual-phase oxygen transport membranes are fast-growing research interest for application in oxyfuel combustion process. One such potential candidate is CGO-FCO (60 wt% Ce0.8Gd0.2O2−δ–40 wt% FeCo2O4) identified to provide good oxygen permeation flux with substantial stability in harsh atmosphere. Dense CGO-FCO membranes of 1 mm thickness were fabricated by sintering dry pellets pressed from powders synthesized by one-pot method (modified Pechini process) at 1200°C for 10 h. Microstructure analysis indicates presence of a third orthorhombic perovskite phase in the sintered composite. It was also identified that the spinel phase tends to form an oxygen deficient phase at the grain boundary of spinel and CGO phases. Surface exchange limitation of the membranes was overcome by La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF) porous layer coating over the composite. The oxygen permeation flux of the CGO-FCO screen printed with a porous layer of 10 μm thick LSCF is 0.11 mL/cm2 per minute at 850°C with argon as sweep and air as feed gas at the rates of 50 and 250 mL/min.
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90.
  • Revel, A., et al. (författare)
  • Strong Neutron Pairing in core+4n Nuclei
  • 2018
  • Ingår i: Physical Review Letters. - 1079-7114 .- 0031-9007. ; 120:15
  • Tidskriftsartikel (refereegranskat)abstract
    • The emission of neutron pairs from the neutron-rich N=12 isotones C18 and O20 has been studied by high-energy nucleon knockout from N19 and O21 secondary beams, populating unbound states of the two isotones up to 15 MeV above their two-neutron emission thresholds. The analysis of triple fragment-n-n correlations shows that the decay N19(-1p)C18∗→C16+n+n is clearly dominated by direct pair emission. The two-neutron correlation strength, the largest ever observed, suggests the predominance of a C14 core surrounded by four valence neutrons arranged in strongly correlated pairs. On the other hand, a significant competition of a sequential branch is found in the decay O21(-1n)O20∗→O18+n+n, attributed to its formation through the knockout of a deeply bound neutron that breaks the O16 core and reduces the number of pairs.
  •  
91.
  • Rich, Evan A., et al. (författare)
  • Multi-epoch Direct Imaging and Time-variable Scattered Light Morphology of the HD 163296 Protoplanetary Disk
  • 2019
  • Ingår i: Astrophysical Journal. - : American Astronomical Society. - 0004-637X .- 1538-4357. ; 875:1
  • Tidskriftsartikel (refereegranskat)abstract
    • We present H-band polarized scattered light imagery and JHK high-contrast spectroscopy of the protoplanetary disk around HD 163296 observed with the High-Contrast Coronographic Imager for Adaptive Optics (HiCIAO) and Subaru Coronagraphic Extreme Adaptive Optics (SCExAO)/Coronagraphic High Angular Resolution Imaging Spectrograph (CHARTS) instruments at Subaru Observatory. The polarimetric imagery resolve a broken ring structure surrounding HD 163296 that peaks at a distance along the major axis of 0 ''.65 (66 au) and extends out to 0 ''.98 (100 au) along the major axis. Our 2011 H-band data exhibit clear axisymmetry, with the NW and SE side of the disk exhibiting similar intensities. Our data are clearly different from 2016 epoch H-band observations of the Very Large Telescope (VLT)/Spectro-Polarimetric High-contrast Exoplanet REsearch (SPHERE), which found a strong 2.7 x asymmetry between the NW and SE side of the disk. Collectively, these results indicate the presence of time-variable, non-azimuthally symmetric illumination of the outer disk. While our SCExAO/CHARIS data are sensitive enough to recover the planet candidate identified from NIRC2 in the thermal infrared (IR), we fail to detect an object with JHK brightness nominally consistent with this object. This suggests that the candidate is either fainter in JHK bands than model predictions, possibly due to extinction from the disk or atmospheric dust/clouds, or that it is an artifact of the data set/data processing, such as a residual speckle or partially subtracted disk feature. Assuming standard hot-start evolutionary models and a system age of 5 Myr, we set new, direct mass limits for the inner (outer) Atacama Large Millimeter/submillimeter Array (ALMA)-predicted protoplanet candidate along the major (minor) disk axis of of 1.5 (2) M-J.
  •  
92.
  • Rich, Evan A., et al. (författare)
  • NEAR-IR POLARIZED SCATTERED LIGHT IMAGERY OF THE DoAr 28 TRANSITIONAL DISK
  • 2015
  • Ingår i: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 150:3
  • Tidskriftsartikel (refereegranskat)abstract
    • We present the first spatially resolved polarized scattered light H-band detection of the DoAr 28 transitional disk. Our two epochs of imagery detect the scattered light disk from our effective inner working angle of 0.10 (13 AU) out to 0.50 (65 AU). This inner working angle is interior to the location of the system's gap inferred by previous studies using spectral energy distribution modeling (15 AU). We detected a candidate point source companion 1.08 northwest of the system; however, our second epoch of imagery strongly suggests that this object is a background star. We constructed a grid of Monte Carlo Radiative Transfer models of the system, and our best fit models utilize a modestly inclined (50 degrees), 0.01 M-circle dot disk that has a partially depleted inner gap from the dust sublimation radius out to similar to 8 AU. Subtracting this best fit, axi-symmetric model from our polarized intensity data reveals evidence for two small asymmetries in the disk, which could be attributable to a variety of mechanisms.
  •  
93.
  • Rich, Evan A., et al. (författare)
  • The fundamental stellar parameters of FGK stars in the SEEDS survey Norman, OK 73071, USA
  • 2017
  • Ingår i: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 472:2, s. 1736-1752
  • Tidskriftsartikel (refereegranskat)abstract
    • Large exoplanet surveys have successfully detected thousands of exoplanets to-date. Utilizing these detections and non-detections to constrain our understanding of the formation and evolution of planetary systems also requires a detailed understanding of the basic properties of their host stars. We have determined the basic stellar properties of F, K and G stars in the Strategic Exploration of Exoplanets and Disks with Subaru (SEEDS) survey from Echelle spectra taken at the Apache Point Observatory's 3.5m telescope. Using ROBOSPECT to extract line equivalent widths and TemperatureGravity microtrubulentVelocity ITerations to calculate the fundamental parameters, we have computed T-eff, log(g), v(t), [Fe/H], chromospheric activity and the age for our sample. Our methodology was calibrated against previously published results for a portion of our sample. The distribution of [Fe/H] in our sample is consistent with that typical of the Solar neighbourhood. Additionally, we find the ages of most of our sample are < 500 Myr, but note that we cannot determine robust ages from significantly older stars via chromospheric activity age indicators. The futuremeta-analysis of the frequency ofwide stellar and sub-stellar companions imaged via the SEEDS survey will utilize our results to constrain the occurrence of detected comoving companions with the properties of their host stars.
  •  
94.
  • Rigard, Melanie, et al. (författare)
  • Francisella tularensis IglG Belongs to a Novel Family of PAAR-Like T6SS Proteins and Harbors a Unique N-terminal Extension Required for Virulence
  • 2016
  • Ingår i: PLoS Pathogens. - : Public Library of Science (PLoS). - 1553-7366 .- 1553-7374. ; 12:9
  • Tidskriftsartikel (refereegranskat)abstract
    • The virulence of Francisella tularensis, the etiological agent of tularemia, relies on an atypical type VI secretion system ( T6SS) encoded by a genomic island termed the Francisella Pathogenicity Island ( FPI). While the importance of the FPI in F. tularensis virulence is clearly established, the precise role of most of the FPI-encoded proteins remains to be deciphered. In this study, using highly virulent F. tularensis strains and the closely related species F. novicida, IglG was characterized as a protein featuring a unique alpha-helical N-terminal extension and a domain of unknown function ( DUF4280), present in more than 250 bacterial species. Three dimensional modeling of IglG and of the DUF4280 consensus protein sequence indicates that these proteins adopt a PAAR-like fold, suggesting they could cap the T6SS in a similar way as the recently described PAAR proteins. The newly identified PAAR-like motif is characterized by four conserved cysteine residues, also present in IglG, which may bind a metal atom. We demonstrate that IglG binds metal ions and that each individual cysteine is required for T6SS-dependent secretion of IglG and of the Hcp homologue, IglC and for the F. novicida intracellular life cycle. In contrast, the Francisella-specific N-terminal alpha-helical extension is not required for IglG secretion, but is critical for F. novicida virulence and for the interaction of IglG with another FPI-encoded protein, IglF. Altogether, our data suggest that IglG is a PAAR-like protein acting as a bi-modal protein that may connect the tip of the Francisella T6SS with a putative T6SS effector, IglF.
  •  
95.
  • Rugenstein, Maria, et al. (författare)
  • LongRunMIP : Motivation and Design for a Large Collection of Millennial-Length AOGCM Simulations
  • 2019
  • Ingår i: Bulletin of The American Meteorological Society - (BAMS). - 0003-0007 .- 1520-0477. ; 100:12, s. 2551-2570
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a model intercomparison project, LongRunMIP, the first collection of millennial-length (1,000+ years) simulations of complex coupled climate models with a representation of ocean, atmosphere, sea ice, and land surface, and their interactions. Standard model simulations are generally only a few hundred years long. However, modeling the long-term equilibration in response to radiative forcing perturbation is important for understanding many climate phenomena, such as the evolution of ocean circulation, time- and temperature-dependent feedbacks, and the differentiation of forced signal and internal variability. The aim of LongRunMIP is to facilitate research into these questions by serving as an archive for simulations that capture as much of this equilibration as possible. The only requirement to participate in LongRunMIP is to contribute a simulation with elevated, constant CO2 forcing that lasts at least 1,000 years. LongRunMIP is an MIP of opportunity in that the simulations were mostly performed prior to the conception of the archive without an agreed-upon set of experiments. For most models, the archive contains a preindustrial control simulation and simulations with an idealized (typically abrupt) CO2 forcing. We collect 2D surface and top-of-atmosphere fields and 3D ocean temperature and salinity fields. Here, we document the collection of simulations and discuss initial results, including the evolution of surface and deep ocean temperature and cloud radiative effects. As of October 2019, the collection includes 50 simulations of 15 models by 10 modeling centers. The data of LongRunMIP are publicly available. We encourage submissions of more simulations in the future.
  •  
96.
  • Ryu, Tsuguru, et al. (författare)
  • HIGH-CONTRAST IMAGING OF INTERMEDIATE-MASS GIANTS WITH LONG-TERM RADIAL VELOCITY TRENDS
  • 2016
  • Ingår i: Astrophysical Journal. - 0004-637X .- 1538-4357. ; 825:2
  • Tidskriftsartikel (refereegranskat)abstract
    • A radial velocity (RV) survey for intermediate-mass giants has been in operation for over a decade at Okayama Astrophysical Observatory (OAO). The OAO survey has revealed that some giants show long-term linear RV accelerations (RV trends), indicating the presence of outer companions. Direct-imaging observations can help clarify what objects generate these RV trends. We present the results of high-contrast imaging observations of six intermediate-mass giants with long-term RV trends using the Subaru Telescope and HiCIAO camera. We detected co-moving companions to gamma Hya B (0.61(-0.14)(+0.12)M(circle dot)), HD 5608 B (0.10 +/- 0.01M(circle dot)), and HD 109272 B (0.28 +/- 0.06M(circle dot)). For the remaining targets (iota Dra, 18 Del, and HD 14067), we exclude companions more massive than 30-60 M-Jup at projected separations of 1 ''-7 ''. We examine whether these directly imaged companions or unidentified long-period companions can account for the RV trends observed around the six giants. We find that the Kozai mechanism can explain the high eccentricity of the inner planets iota Dra b, HD 5608 b, and HD 14067 b.
  •  
97.
  • Schoville, Sean D., et al. (författare)
  • A model species for agricultural pest genomics : The genome of the Colorado potato beetle, Leptinotarsa decemlineata (Coleoptera: Chrysomelidae)
  • 2018
  • Ingår i: Scientific Reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 8
  • Tidskriftsartikel (refereegranskat)abstract
    • The Colorado potato beetle is one of the most challenging agricultural pests to manage. It has shown a spectacular ability to adapt to a variety of solanaceaeous plants and variable climates during its global invasion, and, notably, to rapidly evolve insecticide resistance. To examine evidence of rapid evolutionary change, and to understand the genetic basis of herbivory and insecticide resistance, we tested for structural and functional genomic changes relative to other arthropod species using genome sequencing, transcriptomics, and community annotation. Two factors that might facilitate rapid evolutionary change include transposable elements, which comprise at least 17% of the genome and are rapidly evolving compared to other Coleoptera, and high levels of nucleotide diversity in rapidly growing pest populations. Adaptations to plant feeding are evident in gene expansions and differential expression of digestive enzymes in gut tissues, as well as expansions of gustatory receptors for bitter tasting. Surprisingly, the suite of genes involved in insecticide resistance is similar to other beetles. Finally, duplications in the RNAi pathway might explain why Leptinotarsa decemlineata has high sensitivity to dsRNA. The L. decemlineata genome provides opportunities to investigate a broad range of phenotypes and to develop sustainable methods to control this widely successful pest.
  •  
98.
  • Seitz, Arne, et al. (författare)
  • Concept validation study for fuselage wake-filling propulsion integration
  • 2018
  • Ingår i: 31st Congress of the International Council of the Aeronautical Sciences, ICAS 2018.
  • Konferensbidrag (refereegranskat)abstract
    • The present paper provides an overview together with intermediate results of the work-in-progress research performed in the EC-funded Horizon 2020 collaborative project CENTRELINE (“ConcEpt validatioN sTudy foR fusElage wake-filLIng propulsioN integration”), aiming at demonstrating the proof of concept for a groundbreaking approach to synergistic propulsion-airframe integration, the so-called Propulsive Fuselage Concept (PFC). The concept features a turbo-electrically driven propulsive device integrated in the very aft-section of the fuselage, dedicated to the purpose of fuselage wake-filling. Currently at TRL 1-2, CENTRELINE's target is to mature the technological key features of the PFC to TRL 3-4. The core of the targeted proof-of-concept is formed by two experimental test campaigns supported by high-fidelity 3D numerical simulation and integrated multidisciplinary design optimisation techniques for aerodynamics, aero-structures as well as the energy and propulsion system.
  •  
99.
  • Sharma, Sapna, et al. (författare)
  • A global database of lake surface temperatures collected by in situ and satellite methods from 1985–2009
  • 2015
  • Ingår i: Scientific Data. - : Macmillan Publishers Limited. - 2052-4463. ; 2
  • Tidskriftsartikel (refereegranskat)abstract
    • Global environmental change has influenced lake surface temperatures, a key driver of ecosystem structure and function. Recent studies have suggested significant warming of water temperatures in individual lakes across many different regions around the world. However, the spatial and temporal coherence associated with the magnitude of these trends remains unclear. Thus, a global data set of water temperature is required to understand and synthesize global, long-term trends in surface water temperatures of inland bodies of water. We assembled a database of summer lake surface temperatures for 291 lakes collected in situ and/or by satellites for the period 1985–2009. In addition, corresponding climatic drivers (air temperatures, solar radiation, and cloud cover) and geomorphometric characteristics (latitude, longitude, elevation, lake surface area, maximum depth, mean depth, and volume) that influence lake surface temperatures were compiled for each lake. This unique dataset offers an invaluable baseline perspective on global-scale lake thermal conditions as environmental change continues.
  •  
100.
  • Sierks, Holger, et al. (författare)
  • On the nucleus structure and activity of comet 67P/Churyumov-Gerasimenko
  • 2015
  • Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 347:6220
  • Tidskriftsartikel (refereegranskat)abstract
    • Images from the OSIRIS scientific imaging system onboard Rosetta show that the nucleus of 67P/Churyumov-Gerasimenko consists of two lobes connected by a short neck. The nucleus has a bulk density less than half that of water. Activity at a distance from the Sun of >3 astronomical units is predominantly from the neck, where jets have been seen consistently. The nucleus rotates about the principal axis of momentum. The surface morphology suggests that the removal of larger volumes of material, possibly via explosive release of subsurface pressure or via creation of overhangs by sublimation, may be a major mass loss process. The shape raises the question of whether the two lobes represent a contact binary formed 4.5 billion years ago, or a single body where a gap has evolved via mass loss.
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