| 1. |
- Callaway, EM, et al.
(författare)
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A multimodal cell census and atlas of the mammalian primary motor cortex
- 2021
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 1476-4687 .- 0028-0836. ; 598:7879, s. 86-102
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Tidskriftsartikel (refereegranskat)abstract
- Here we report the generation of a multimodal cell census and atlas of the mammalian primary motor cortex as the initial product of the BRAIN Initiative Cell Census Network (BICCN). This was achieved by coordinated large-scale analyses of single-cell transcriptomes, chromatin accessibility, DNA methylomes, spatially resolved single-cell transcriptomes, morphological and electrophysiological properties and cellular resolution input–output mapping, integrated through cross-modal computational analysis. Our results advance the collective knowledge and understanding of brain cell-type organization1–5. First, our study reveals a unified molecular genetic landscape of cortical cell types that integrates their transcriptome, open chromatin and DNA methylation maps. Second, cross-species analysis achieves a consensus taxonomy of transcriptomic types and their hierarchical organization that is conserved from mouse to marmoset and human. Third, in situ single-cell transcriptomics provides a spatially resolved cell-type atlas of the motor cortex. Fourth, cross-modal analysis provides compelling evidence for the transcriptomic, epigenomic and gene regulatory basis of neuronal phenotypes such as their physiological and anatomical properties, demonstrating the biological validity and genomic underpinning of neuron types. We further present an extensive genetic toolset for targeting glutamatergic neuron types towards linking their molecular and developmental identity to their circuit function. Together, our results establish a unifying and mechanistic framework of neuronal cell-type organization that integrates multi-layered molecular genetic and spatial information with multi-faceted phenotypic properties.
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| 2. |
- Artibani, Walter, et al.
(författare)
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EAU Policy on Live Surgery Events.
- 2014
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Ingår i: European Urology. - : Elsevier BV. - 1873-7560 .- 0302-2838. ; 66:1, s. 87-97
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Forskningsöversikt (refereegranskat)abstract
- Live surgery is an important part of surgical education, with an increase in the number of live surgery events (LSEs) at meetings despite controversy about their real educational value, risks to patient safety, and conflicts of interest.
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| 3. |
- Martinsson, Bengt, et al.
(författare)
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Comparison between CARIBIC Aerosol Samples Analysed by Accelerator-Based Methods and Optical Particle Counter Measurements
- 2014
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Ingår i: Atmospheric Measurement Techniques. - : Copernicus GmbH. - 1867-1381 .- 1867-8548. ; 7:8, s. 2581-2596
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Tidskriftsartikel (refereegranskat)abstract
- Inter-comparison of results from two kinds of aerosol systems in the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on a Instrument Container) passenger aircraft based observatory, operating during intercontinental flights at 9-12 km altitude, is presented. Aerosol from the lowermost stratosphere (LMS), the extra-tropical upper troposphere (UT) and the tropical mid troposphere (MT) were investigated. Aerosol particle volume concentration measured with an optical particle counter (OPC) is compared with analytical results of the sum of masses of all major and several minor constituents from aerosol samples collected with an impactor. Analyses were undertaken with the following accelerator-based methods: particle-induced X-ray emission (PIXE) and particle elastic scattering analysis (PESA). Data from 48 flights during 1 year are used, leading to a total of 106 individual comparisons. The ratios of the particle volume from the OPC and the total mass from the analyses were in 84% within a relatively narrow interval. Data points outside this interval are connected with inlet-related effects in clouds, large variability in aerosol composition, particle size distribution effects and some cases of non-ideal sampling. Overall, the comparison of these two CARIBIC measurements based on vastly different methods show good agreement, implying that the chemical and size information can be combined in studies of the MT/UT/LMS aerosol.
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| 4. |
- Andersson, Sandra, et al.
(författare)
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Composition and evolution of volcanic aerosol from eruptions of Kasatochi, Sarychev and Eyjafjallajokull in 2008-2010 based on CARIBIC observations
- 2013
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Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7324. ; 13:4, s. 1781-1796
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Tidskriftsartikel (refereegranskat)abstract
- Large volcanic eruptions impact significantly on climate and lead to ozone depletion due to injection of particles and gases into the stratosphere where their residence times are long. In this the composition of volcanic aerosol is an important but inadequately studied factor. Samples of volcanically influenced aerosol were collected following the Kasatochi (Alaska), Sarychev (Russia) and also during the Eyjafjallajokull (Iceland) eruptions in the period 2008-2010. Sampling was conducted by the CARIBIC platform during regular flights at an altitude of 10-12 km as well as during dedicated flights through the volcanic clouds from the eruption of Eyjafjallajokull in spring 2010. Elemental concentrations of the collected aerosol were obtained by accelerator-based analysis. Aerosol from the Eyjafjallajokull volcanic clouds was identified by high concentrations of sulphur and elements pointing to crustal origin, and confirmed by trajectory analysis. Signatures of volcanic influence were also used to detect volcanic aerosol in stratospheric samples collected following the Sarychev and Kasatochi eruptions. In total it was possible to identify 17 relevant samples collected between 1 and more than 100 days following the eruptions studied. The volcanically influenced aerosol mainly consisted of ash, sulphate and included a carbonaceous component. Samples collected in the volcanic cloud from Eyjafjallajokull were dominated by the ash and sulphate component (similar to 45% each) while samples collected in the tropopause region and LMS mainly consisted of sulphate (50-77%) and carbon (21-43%). These fractions were increasing/decreasing with the age of the aerosol. Because of the long observation period, it was possible to analyze the evolution of the relationship between the ash and sulphate components of the volcanic aerosol. From this analysis the residence time (1/e) of sulphur dioxide in the studied volcanic cloud was estimated to be 45 +/- 22 days.
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| 5. |
- Rauthe-Schoech, A., et al.
(författare)
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CARIBIC aircraft measurements of Eyjafjallajokull volcanic clouds in April/May 2010
- 2012
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Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7324. ; 12:2, s. 879-902
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Tidskriftsartikel (refereegranskat)abstract
- The Civil Aircraft for the Regular Investigation of the Atmosphere Based on an Instrument Container (CARIBIC) project investigates physical and chemical processes in the Earth's atmosphere using a Lufthansa Airbus long-distance passenger aircraft. After the beginning of the explosive eruption of the Eyjafjallajokull volcano on Iceland on 14 April 2010, the first CARIBIC volcano-specific measurement flight was carried out over the Baltic Sea and Southern Sweden on 20 April. Two more flights followed: one over Ireland and the Irish Sea on 16 May and the other over the Norwegian Sea on 19 May 2010. During these three special mission flights the CARIBIC container proved its merits as a comprehensive flying laboratory. The elemental composition of particles collected over the Baltic Sea during the first flight (20 April) indicated the presence of volcanic ash. Over Northern Ireland and the Irish Sea (16 May), the DOAS system detected SO2 and BrO co-located with volcanic ash particles that increased the aerosol optical depth. Over the Norwegian Sea (19 May), the optical particle counter detected a strong increase of particles larger than 400 nm diameter in a region where ash clouds were predicted by aerosol dispersion models. Aerosol particle samples collected over the Irish Sea and the Norwegian Sea showed large relative enhancements of the elements silicon, iron, titanium and calcium. Non-methane hydrocarbon concentrations in whole air samples collected on 16 and 19 May 2010 showed a pattern of removal of several hydrocarbons that is typical for chlorine chemistry in the volcanic clouds. Comparisons of measured ash concentrations and simulations with the FLEXPART dispersion model demonstrate the difficulty of detailed volcanic ash dispersion modelling due to the large variability of the volcanic cloud sources, extent and patchiness as well as the thin ash layers formed in the volcanic clouds.
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| 6. |
- Heue, K-P, et al.
(författare)
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SO2 and BrO observation in the plume of the Eyjafjallajokull volcano 2010: CARIBIC and GOME-2 retrievals
- 2011
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Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7324. ; 11:6, s. 2973-2989
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Tidskriftsartikel (refereegranskat)abstract
- The ash cloud of the Eyjafjallajokull (also referred to as: Eyjafjalla (e.g. Schumann et al., 2011), Eyjafjoll or Eyjafjoll (e.g. Ansmann et al., 2010)) volcano on Iceland caused closure of large parts of European airspace in April and May 2010. For the validation and improvement of the European volcanic ash forecast models several research flights were performed. Also the CARIBIC (Civil Aircraft for the Regular Investigation of the atmosphere Based on an Instrument Container) flying laboratory, which routinely measures at cruise altitude (approximate to 11 km) performed three dedicated measurements flights through sections of the ash plume. Although the focus of these flights was on the detection and quantification of the volcanic ash, we report here on sulphur dioxide (SO2) and bromine monoxide (BrO) measurements with the CARIBIC DOAS (Differential Optical Absorption Spectroscopy) instrument during the second of these special flights on 16 May 2010. As the BrO and the SO2 observations coincide, we assume the BrO to have been formed inside the volcanic plume. Average SO2 and BrO mixing ratios of approximate to 40 ppb and approximate to 5 ppt respectively are retrieved inside the plume. The BrO to SO2 ratio retrieved from the CARIBIC observation is approximate to 1.3x10(-4). Both SO2 and BrO observations agree well with simultaneous satellite (GOME-2) observations. SO2 column densities retrieved from satellite observations are often used as an indicator for volcanic ash. As the CARIBIC O-4 column densities changed rapidly during the plume observation, we conclude that the aerosol and the SO2 plume are collocated. For SO2 some additional information on the local distribution can be derived from a comparison of forward and back scan GOME-2 data. More details on the local plume size and position are retrieved by combining CARIBIC and GOME-2 data.
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| 7. |
- Ruti, P. M., et al.
(författare)
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The West African climate system: a review of the AMMA model inter-comparison initiatives
- 2011
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Ingår i: Atmospheric Science Letters. - : Wiley. - 1530-261X. ; 12:1, s. 116-122
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Tidskriftsartikel (refereegranskat)abstract
- We review the African Monsoon Multidisciplinary Analysis (AMMA) model inter-comparison activities for West Africa. The Model Inter-comparison Project is an evaluation exercise of how global and regional atmospheric models represent seasonal and intra-seasonal variations of the climate and rainfall over the Sahel. The Land surface Model Inter-comparison Project in turn focuses on modelling critical land surface processes over West Africa and on their link with the atmosphere. The CHEmistry Model Inter-comparison Project (CHEMIP) is a comparison of the tropospheric composition as simulated by a number of Chemical Transport Models (CTM) and Chemistry-Climate Models. We highlight the main model limitations and provide recommendations for future development. Copyright. (C) 2011 Royal Meteorological Society
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| 8. |
- Heue, K. -P., et al.
(författare)
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Observations of the 2008 Kasatochi volcanic SO2 plume by CARIBIC aircraft DOAS and the GOME-2 satellite
- 2010
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Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7324. ; 10:10, s. 4699-4713
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Tidskriftsartikel (refereegranskat)abstract
- The 2008 Kasatochi volcanic eruption emitted 1.5-2.5 Tg SO2 into the upper troposphere and lower stratosphere. Parts of the main volcanic plume (gases and particles) reached central Europe a week after the eruption and were detected there by the CARIBIC (Civil Aircraft for Regular investigation of the Atmosphere based on an Instrument Container) flying observatory. The plume was also observed by the GOME-2 satellite instrument, only a few hours after the CARIBIC aircraft had crossed the plume, thus giving a unique opportunity to compare results. Trajectories and local wind speeds are investigated in detail using the GOME-2 and CARIBIC observations for better comparison of the results from these two observational systems. A comparison of the satellite spatial pattern with the local observations of the wind speed and the trajectory model TRAJKS showed a slight discrepancy, which has to be considered for satellite validation. Hence, it appears that detailed analyses of wind speeds are required. Emitted and secondary particles, partly measured and sampled by the CARIBIC in situ instruments, affected the DOAS SO2 measurements, of both CARIBIC and GOME-2. Overall GOME-2 and the CARIBIC SO2 measurements agree very well. The major uncertainties remain the actual wind speed needed to properly correct for the advection of the plume between the different overpass times and effects of aerosols on DOAS retrievals. The good agreement can be seen as validation for both GOME-2 and CARIBIC DOAS observations.
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| 9. |
- Martinsson, Bengt, et al.
(författare)
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Influence of the 2008 Kasatochi volcanic eruption on sulfurous and carbonaceous aerosol constituents in the lower stratosphere
- 2009
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Ingår i: Geophysical Research Letters. - 1944-8007. ; 36
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Tidskriftsartikel (refereegranskat)abstract
- Influences on stratospheric aerosol during the first four months following the eruption of Kasatochi volcano (Alaska) were studied using observations at 10700 +/- 600 m altitude from the CARIBIC platform. Collected aerosol samples were analyzed for elemental constituents. Particle number concentrations were recorded in three size intervals together with ozone mixing ratios and slant column densities of SO2. The eruption increased particulate sulfur concentrations by a factor of up to 10 compared to periods before the eruption (1999-2002 and 2005-August 2008). Three to four months later, the concentration was still elevated by a factor of 3 in the lowermost stratosphere at northern midlatitudes. Besides sulfur, the Kasatochi aerosol contained a significant carbonaceous component and ash that declined in time after the eruption. The carbon-to-sulfur mass concentration ratio of the volcanic aerosol was 2.6 seven days after the eruption and reached 1.2 after 3 - 4 months. Citation: Martinsson, B. G., C. A. M. Brenninkmeijer, S. A. Carn, M. Hermann, K.-P. Heue, P. F. J. van Velthoven, and A. Zahn (2009), Influence of the 2008 Kasatochi volcanic eruption on sulfurous and carbonaceous aerosol constituents in the lower stratosphere, Geophys. Res. Lett., 36, L12813, doi: 10.1029/2009GL038735.
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| 10. |
- Hermann, M, et al.
(författare)
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Submicrometer aerosol particle distributions in the upper troposphere over the mid-latitude North Atlantic - Results from the third route of 'CARIBIC'
- 2008
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Ingår i: Tellus. Series B: Chemical and Physical Meteorology. - : Stockholm University Press. - 0280-6509 .- 1600-0889. ; 60:1, s. 106-117
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Tidskriftsartikel (refereegranskat)abstract
- Particle number and mass concentrations of submicrometer aerosol particles were determined for the upper troposphere over the mid-latitude North Atlantic within the Civil Aircraft for Regular Investigation of the Atmosphere Based on an Instrument Container project (CARIBIC, http://www.caribic-atmospheric.com). Between May 2001 and April 2002, 22 flights from Germany to the Caribbean were conducted using an automated measurement container on a B767 passenger aircraft. Spatial and seasonal probability distributions for ultrafine and Aitken mode particles as well as mass concentrations of particulate sulphur in 8-12 km altitude are presented. High particle number concentrations (mostly 2500-15 000 particles cm(-3) STP) are particularly found in summer over the western North Atlantic Ocean close to the North American continent. The distributions together with an analysis of particle source processes show that deep vertical transport is the dominant process leading to most of the events with high particle number concentrations (greater than or similar to 8000 particles cm(-3) STP) for ultrafine particles as well as for Aitken mode particles. This study emphasizes the importance of deep vertical transport and cloud processing for the concentration of aerosol particles in the upper troposphere.
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